postgresql/src/interfaces/libpq/fe-connect.c

7242 lines
180 KiB
C

/*-------------------------------------------------------------------------
*
* fe-connect.c
* functions related to setting up a connection to the backend
*
* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/interfaces/libpq/fe-connect.c
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <sys/stat.h>
#include <fcntl.h>
#include <ctype.h>
#include <time.h>
#include <unistd.h>
#include "common/ip.h"
#include "common/link-canary.h"
#include "common/scram-common.h"
#include "common/string.h"
#include "fe-auth.h"
#include "libpq-fe.h"
#include "libpq-int.h"
#include "mb/pg_wchar.h"
#include "pg_config_paths.h"
#include "port/pg_bswap.h"
#ifdef WIN32
#include "win32.h"
#ifdef _WIN32_IE
#undef _WIN32_IE
#endif
#define _WIN32_IE 0x0500
#ifdef near
#undef near
#endif
#define near
#include <shlobj.h>
#ifdef _MSC_VER /* mstcpip.h is missing on mingw */
#include <mstcpip.h>
#endif
#else
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#ifdef HAVE_NETINET_TCP_H
#include <netinet/tcp.h>
#endif
#endif
#ifdef ENABLE_THREAD_SAFETY
#ifdef WIN32
#include "pthread-win32.h"
#else
#include <pthread.h>
#endif
#endif
#ifdef USE_LDAP
#ifdef WIN32
#include <winldap.h>
#else
/* OpenLDAP deprecates RFC 1823, but we want standard conformance */
#define LDAP_DEPRECATED 1
#include <ldap.h>
typedef struct timeval LDAP_TIMEVAL;
#endif
static int ldapServiceLookup(const char *purl, PQconninfoOption *options,
PQExpBuffer errorMessage);
#endif
#ifndef WIN32
#define PGPASSFILE ".pgpass"
#else
#define PGPASSFILE "pgpass.conf"
#endif
/*
* Pre-9.0 servers will return this SQLSTATE if asked to set
* application_name in a startup packet. We hard-wire the value rather
* than looking into errcodes.h since it reflects historical behavior
* rather than that of the current code.
*/
#define ERRCODE_APPNAME_UNKNOWN "42704"
/* This is part of the protocol so just define it */
#define ERRCODE_INVALID_PASSWORD "28P01"
/* This too */
#define ERRCODE_CANNOT_CONNECT_NOW "57P03"
/*
* Cope with the various platform-specific ways to spell TCP keepalive socket
* options. This doesn't cover Windows, which as usual does its own thing.
*/
#if defined(TCP_KEEPIDLE)
/* TCP_KEEPIDLE is the name of this option on Linux and *BSD */
#define PG_TCP_KEEPALIVE_IDLE TCP_KEEPIDLE
#define PG_TCP_KEEPALIVE_IDLE_STR "TCP_KEEPIDLE"
#elif defined(TCP_KEEPALIVE_THRESHOLD)
/* TCP_KEEPALIVE_THRESHOLD is the name of this option on Solaris >= 11 */
#define PG_TCP_KEEPALIVE_IDLE TCP_KEEPALIVE_THRESHOLD
#define PG_TCP_KEEPALIVE_IDLE_STR "TCP_KEEPALIVE_THRESHOLD"
#elif defined(TCP_KEEPALIVE) && defined(__darwin__)
/* TCP_KEEPALIVE is the name of this option on macOS */
/* Caution: Solaris has this symbol but it means something different */
#define PG_TCP_KEEPALIVE_IDLE TCP_KEEPALIVE
#define PG_TCP_KEEPALIVE_IDLE_STR "TCP_KEEPALIVE"
#endif
/*
* fall back options if they are not specified by arguments or defined
* by environment variables
*/
#define DefaultHost "localhost"
#define DefaultTty ""
#define DefaultOption ""
#define DefaultAuthtype ""
#ifdef USE_SSL
#define DefaultChannelBinding "prefer"
#else
#define DefaultChannelBinding "disable"
#endif
#define DefaultTargetSessionAttrs "any"
#ifdef USE_SSL
#define DefaultSSLMode "prefer"
#else
#define DefaultSSLMode "disable"
#endif
#ifdef ENABLE_GSS
#include "fe-gssapi-common.h"
#define DefaultGSSMode "prefer"
#else
#define DefaultGSSMode "disable"
#endif
/* ----------
* Definition of the conninfo parameters and their fallback resources.
*
* If Environment-Var and Compiled-in are specified as NULL, no
* fallback is available. If after all no value can be determined
* for an option, an error is returned.
*
* The value for the username is treated specially in conninfo_add_defaults.
* If the value is not obtained any other way, the username is determined
* by pg_fe_getauthname().
*
* The Label and Disp-Char entries are provided for applications that
* want to use PQconndefaults() to create a generic database connection
* dialog. Disp-Char is defined as follows:
* "" Normal input field
* "*" Password field - hide value
* "D" Debug option - don't show by default
*
* PQconninfoOptions[] is a constant static array that we use to initialize
* a dynamically allocated working copy. All the "val" fields in
* PQconninfoOptions[] *must* be NULL. In a working copy, non-null "val"
* fields point to malloc'd strings that should be freed when the working
* array is freed (see PQconninfoFree).
*
* The first part of each struct is identical to the one in libpq-fe.h,
* which is required since we memcpy() data between the two!
* ----------
*/
typedef struct _internalPQconninfoOption
{
char *keyword; /* The keyword of the option */
char *envvar; /* Fallback environment variable name */
char *compiled; /* Fallback compiled in default value */
char *val; /* Option's current value, or NULL */
char *label; /* Label for field in connect dialog */
char *dispchar; /* Indicates how to display this field in a
* connect dialog. Values are: "" Display
* entered value as is "*" Password field -
* hide value "D" Debug option - don't show
* by default */
int dispsize; /* Field size in characters for dialog */
/* ---
* Anything above this comment must be synchronized with
* PQconninfoOption in libpq-fe.h, since we memcpy() data
* between them!
* ---
*/
off_t connofs; /* Offset into PGconn struct, -1 if not there */
} internalPQconninfoOption;
static const internalPQconninfoOption PQconninfoOptions[] = {
/*
* "authtype" is no longer used, so mark it "don't show". We keep it in
* the array so as not to reject conninfo strings from old apps that might
* still try to set it.
*/
{"authtype", "PGAUTHTYPE", DefaultAuthtype, NULL,
"Database-Authtype", "D", 20, -1},
{"service", "PGSERVICE", NULL, NULL,
"Database-Service", "", 20, -1},
{"user", "PGUSER", NULL, NULL,
"Database-User", "", 20,
offsetof(struct pg_conn, pguser)},
{"password", "PGPASSWORD", NULL, NULL,
"Database-Password", "*", 20,
offsetof(struct pg_conn, pgpass)},
{"passfile", "PGPASSFILE", NULL, NULL,
"Database-Password-File", "", 64,
offsetof(struct pg_conn, pgpassfile)},
{"channel_binding", "PGCHANNELBINDING", NULL, NULL,
"Channel-Binding", "", 7, /* sizeof("require") */
offsetof(struct pg_conn, channel_binding)},
{"connect_timeout", "PGCONNECT_TIMEOUT", NULL, NULL,
"Connect-timeout", "", 10, /* strlen(INT32_MAX) == 10 */
offsetof(struct pg_conn, connect_timeout)},
{"dbname", "PGDATABASE", NULL, NULL,
"Database-Name", "", 20,
offsetof(struct pg_conn, dbName)},
{"host", "PGHOST", NULL, NULL,
"Database-Host", "", 40,
offsetof(struct pg_conn, pghost)},
{"hostaddr", "PGHOSTADDR", NULL, NULL,
"Database-Host-IP-Address", "", 45,
offsetof(struct pg_conn, pghostaddr)},
{"port", "PGPORT", DEF_PGPORT_STR, NULL,
"Database-Port", "", 6,
offsetof(struct pg_conn, pgport)},
{"client_encoding", "PGCLIENTENCODING", NULL, NULL,
"Client-Encoding", "", 10,
offsetof(struct pg_conn, client_encoding_initial)},
/*
* "tty" is no longer used either, but keep it present for backwards
* compatibility.
*/
{"tty", "PGTTY", DefaultTty, NULL,
"Backend-Debug-TTY", "D", 40,
offsetof(struct pg_conn, pgtty)},
{"options", "PGOPTIONS", DefaultOption, NULL,
"Backend-Options", "", 40,
offsetof(struct pg_conn, pgoptions)},
{"application_name", "PGAPPNAME", NULL, NULL,
"Application-Name", "", 64,
offsetof(struct pg_conn, appname)},
{"fallback_application_name", NULL, NULL, NULL,
"Fallback-Application-Name", "", 64,
offsetof(struct pg_conn, fbappname)},
{"keepalives", NULL, NULL, NULL,
"TCP-Keepalives", "", 1, /* should be just '0' or '1' */
offsetof(struct pg_conn, keepalives)},
{"keepalives_idle", NULL, NULL, NULL,
"TCP-Keepalives-Idle", "", 10, /* strlen(INT32_MAX) == 10 */
offsetof(struct pg_conn, keepalives_idle)},
{"keepalives_interval", NULL, NULL, NULL,
"TCP-Keepalives-Interval", "", 10, /* strlen(INT32_MAX) == 10 */
offsetof(struct pg_conn, keepalives_interval)},
{"keepalives_count", NULL, NULL, NULL,
"TCP-Keepalives-Count", "", 10, /* strlen(INT32_MAX) == 10 */
offsetof(struct pg_conn, keepalives_count)},
{"tcp_user_timeout", NULL, NULL, NULL,
"TCP-User-Timeout", "", 10, /* strlen(INT32_MAX) == 10 */
offsetof(struct pg_conn, pgtcp_user_timeout)},
/*
* ssl options are allowed even without client SSL support because the
* client can still handle SSL modes "disable" and "allow". Other
* parameters have no effect on non-SSL connections, so there is no reason
* to exclude them since none of them are mandatory.
*/
{"sslmode", "PGSSLMODE", DefaultSSLMode, NULL,
"SSL-Mode", "", 12, /* sizeof("verify-full") == 12 */
offsetof(struct pg_conn, sslmode)},
{"sslcompression", "PGSSLCOMPRESSION", "0", NULL,
"SSL-Compression", "", 1,
offsetof(struct pg_conn, sslcompression)},
{"sslcert", "PGSSLCERT", NULL, NULL,
"SSL-Client-Cert", "", 64,
offsetof(struct pg_conn, sslcert)},
{"sslkey", "PGSSLKEY", NULL, NULL,
"SSL-Client-Key", "", 64,
offsetof(struct pg_conn, sslkey)},
{"sslpassword", NULL, NULL, NULL,
"SSL-Client-Key-Password", "*", 20,
offsetof(struct pg_conn, sslpassword)},
{"sslrootcert", "PGSSLROOTCERT", NULL, NULL,
"SSL-Root-Certificate", "", 64,
offsetof(struct pg_conn, sslrootcert)},
{"sslcrl", "PGSSLCRL", NULL, NULL,
"SSL-Revocation-List", "", 64,
offsetof(struct pg_conn, sslcrl)},
{"requirepeer", "PGREQUIREPEER", NULL, NULL,
"Require-Peer", "", 10,
offsetof(struct pg_conn, requirepeer)},
{"sslminprotocolversion", "PGSSLMINPROTOCOLVERSION", NULL, NULL,
"SSL-Minimum-Protocol-Version", "", 8, /* sizeof("TLSv1.x") == 8 */
offsetof(struct pg_conn, sslminprotocolversion)},
{"sslmaxprotocolversion", "PGSSLMAXPROTOCOLVERSION", NULL, NULL,
"SSL-Maximum-Protocol-Version", "", 8, /* sizeof("TLSv1.x") == 8 */
offsetof(struct pg_conn, sslmaxprotocolversion)},
/*
* As with SSL, all GSS options are exposed even in builds that don't have
* support.
*/
{"gssencmode", "PGGSSENCMODE", DefaultGSSMode, NULL,
"GSSENC-Mode", "", 7, /* sizeof("disable") == 7 */
offsetof(struct pg_conn, gssencmode)},
/* Kerberos and GSSAPI authentication support specifying the service name */
{"krbsrvname", "PGKRBSRVNAME", PG_KRB_SRVNAM, NULL,
"Kerberos-service-name", "", 20,
offsetof(struct pg_conn, krbsrvname)},
{"gsslib", "PGGSSLIB", NULL, NULL,
"GSS-library", "", 7, /* sizeof("gssapi") = 7 */
offsetof(struct pg_conn, gsslib)},
{"replication", NULL, NULL, NULL,
"Replication", "D", 5,
offsetof(struct pg_conn, replication)},
{"target_session_attrs", "PGTARGETSESSIONATTRS",
DefaultTargetSessionAttrs, NULL,
"Target-Session-Attrs", "", 11, /* sizeof("read-write") = 11 */
offsetof(struct pg_conn, target_session_attrs)},
/* Terminating entry --- MUST BE LAST */
{NULL, NULL, NULL, NULL,
NULL, NULL, 0}
};
static const PQEnvironmentOption EnvironmentOptions[] =
{
/* common user-interface settings */
{
"PGDATESTYLE", "datestyle"
},
{
"PGTZ", "timezone"
},
/* internal performance-related settings */
{
"PGGEQO", "geqo"
},
{
NULL, NULL
}
};
/* The connection URI must start with either of the following designators: */
static const char uri_designator[] = "postgresql://";
static const char short_uri_designator[] = "postgres://";
static bool connectOptions1(PGconn *conn, const char *conninfo);
static bool connectOptions2(PGconn *conn);
static int connectDBStart(PGconn *conn);
static int connectDBComplete(PGconn *conn);
static PGPing internal_ping(PGconn *conn);
static PGconn *makeEmptyPGconn(void);
static bool fillPGconn(PGconn *conn, PQconninfoOption *connOptions);
static void freePGconn(PGconn *conn);
static void closePGconn(PGconn *conn);
static void release_conn_addrinfo(PGconn *conn);
static void sendTerminateConn(PGconn *conn);
static PQconninfoOption *conninfo_init(PQExpBuffer errorMessage);
static PQconninfoOption *parse_connection_string(const char *conninfo,
PQExpBuffer errorMessage, bool use_defaults);
static int uri_prefix_length(const char *connstr);
static bool recognized_connection_string(const char *connstr);
static PQconninfoOption *conninfo_parse(const char *conninfo,
PQExpBuffer errorMessage, bool use_defaults);
static PQconninfoOption *conninfo_array_parse(const char *const *keywords,
const char *const *values, PQExpBuffer errorMessage,
bool use_defaults, int expand_dbname);
static bool conninfo_add_defaults(PQconninfoOption *options,
PQExpBuffer errorMessage);
static PQconninfoOption *conninfo_uri_parse(const char *uri,
PQExpBuffer errorMessage, bool use_defaults);
static bool conninfo_uri_parse_options(PQconninfoOption *options,
const char *uri, PQExpBuffer errorMessage);
static bool conninfo_uri_parse_params(char *params,
PQconninfoOption *connOptions,
PQExpBuffer errorMessage);
static char *conninfo_uri_decode(const char *str, PQExpBuffer errorMessage);
static bool get_hexdigit(char digit, int *value);
static const char *conninfo_getval(PQconninfoOption *connOptions,
const char *keyword);
static PQconninfoOption *conninfo_storeval(PQconninfoOption *connOptions,
const char *keyword, const char *value,
PQExpBuffer errorMessage, bool ignoreMissing, bool uri_decode);
static PQconninfoOption *conninfo_find(PQconninfoOption *connOptions,
const char *keyword);
static void defaultNoticeReceiver(void *arg, const PGresult *res);
static void defaultNoticeProcessor(void *arg, const char *message);
static int parseServiceInfo(PQconninfoOption *options,
PQExpBuffer errorMessage);
static int parseServiceFile(const char *serviceFile,
const char *service,
PQconninfoOption *options,
PQExpBuffer errorMessage,
bool *group_found);
static char *pwdfMatchesString(char *buf, const char *token);
static char *passwordFromFile(const char *hostname, const char *port, const char *dbname,
const char *username, const char *pgpassfile);
static void pgpassfileWarning(PGconn *conn);
static void default_threadlock(int acquire);
static bool sslVerifyProtocolVersion(const char *version);
static bool sslVerifyProtocolRange(const char *min, const char *max);
/* global variable because fe-auth.c needs to access it */
pgthreadlock_t pg_g_threadlock = default_threadlock;
/*
* pqDropConnection
*
* Close any physical connection to the server, and reset associated
* state inside the connection object. We don't release state that
* would be needed to reconnect, though, nor local state that might still
* be useful later.
*
* We can always flush the output buffer, since there's no longer any hope
* of sending that data. However, unprocessed input data might still be
* valuable, so the caller must tell us whether to flush that or not.
*/
void
pqDropConnection(PGconn *conn, bool flushInput)
{
/* Drop any SSL state */
pqsecure_close(conn);
/* Close the socket itself */
if (conn->sock != PGINVALID_SOCKET)
closesocket(conn->sock);
conn->sock = PGINVALID_SOCKET;
/* Optionally discard any unread data */
if (flushInput)
conn->inStart = conn->inCursor = conn->inEnd = 0;
/* Always discard any unsent data */
conn->outCount = 0;
/* Free authentication/encryption state */
#ifdef ENABLE_GSS
{
OM_uint32 min_s;
if (conn->gctx)
gss_delete_sec_context(&min_s, &conn->gctx, GSS_C_NO_BUFFER);
if (conn->gtarg_nam)
gss_release_name(&min_s, &conn->gtarg_nam);
if (conn->gss_SendBuffer)
{
free(conn->gss_SendBuffer);
conn->gss_SendBuffer = NULL;
}
if (conn->gss_RecvBuffer)
{
free(conn->gss_RecvBuffer);
conn->gss_RecvBuffer = NULL;
}
if (conn->gss_ResultBuffer)
{
free(conn->gss_ResultBuffer);
conn->gss_ResultBuffer = NULL;
}
}
#endif
#ifdef ENABLE_SSPI
if (conn->sspitarget)
{
free(conn->sspitarget);
conn->sspitarget = NULL;
}
if (conn->sspicred)
{
FreeCredentialsHandle(conn->sspicred);
free(conn->sspicred);
conn->sspicred = NULL;
}
if (conn->sspictx)
{
DeleteSecurityContext(conn->sspictx);
free(conn->sspictx);
conn->sspictx = NULL;
}
conn->usesspi = 0;
#endif
if (conn->sasl_state)
{
/*
* XXX: if support for more authentication mechanisms is added, this
* needs to call the right 'free' function.
*/
pg_fe_scram_free(conn->sasl_state);
conn->sasl_state = NULL;
}
}
/*
* pqDropServerData
*
* Clear all connection state data that was received from (or deduced about)
* the server. This is essential to do between connection attempts to
* different servers, else we may incorrectly hold over some data from the
* old server.
*
* It would be better to merge this into pqDropConnection, perhaps, but
* right now we cannot because that function is called immediately on
* detection of connection loss (cf. pqReadData, for instance). This data
* should be kept until we are actually starting a new connection.
*/
static void
pqDropServerData(PGconn *conn)
{
PGnotify *notify;
pgParameterStatus *pstatus;
/* Forget pending notifies */
notify = conn->notifyHead;
while (notify != NULL)
{
PGnotify *prev = notify;
notify = notify->next;
free(prev);
}
conn->notifyHead = conn->notifyTail = NULL;
/* Reset ParameterStatus data, as well as variables deduced from it */
pstatus = conn->pstatus;
while (pstatus != NULL)
{
pgParameterStatus *prev = pstatus;
pstatus = pstatus->next;
free(prev);
}
conn->pstatus = NULL;
conn->client_encoding = PG_SQL_ASCII;
conn->std_strings = false;
conn->sversion = 0;
/* Drop large-object lookup data */
if (conn->lobjfuncs)
free(conn->lobjfuncs);
conn->lobjfuncs = NULL;
/* Reset assorted other per-connection state */
conn->last_sqlstate[0] = '\0';
conn->auth_req_received = false;
conn->password_needed = false;
conn->write_failed = false;
if (conn->write_err_msg)
free(conn->write_err_msg);
conn->write_err_msg = NULL;
conn->be_pid = 0;
conn->be_key = 0;
}
/*
* Connecting to a Database
*
* There are now six different ways a user of this API can connect to the
* database. Two are not recommended for use in new code, because of their
* lack of extensibility with respect to the passing of options to the
* backend. These are PQsetdb and PQsetdbLogin (the former now being a macro
* to the latter).
*
* If it is desired to connect in a synchronous (blocking) manner, use the
* function PQconnectdb or PQconnectdbParams. The former accepts a string of
* option = value pairs (or a URI) which must be parsed; the latter takes two
* NULL terminated arrays instead.
*
* To connect in an asynchronous (non-blocking) manner, use the functions
* PQconnectStart or PQconnectStartParams (which differ in the same way as
* PQconnectdb and PQconnectdbParams) and PQconnectPoll.
*
* Internally, the static functions connectDBStart, connectDBComplete
* are part of the connection procedure.
*/
/*
* PQconnectdbParams
*
* establishes a connection to a postgres backend through the postmaster
* using connection information in two arrays.
*
* The keywords array is defined as
*
* const char *params[] = {"option1", "option2", NULL}
*
* The values array is defined as
*
* const char *values[] = {"value1", "value2", NULL}
*
* Returns a PGconn* which is needed for all subsequent libpq calls, or NULL
* if a memory allocation failed.
* If the status field of the connection returned is CONNECTION_BAD,
* then some fields may be null'ed out instead of having valid values.
*
* You should call PQfinish (if conn is not NULL) regardless of whether this
* call succeeded.
*/
PGconn *
PQconnectdbParams(const char *const *keywords,
const char *const *values,
int expand_dbname)
{
PGconn *conn = PQconnectStartParams(keywords, values, expand_dbname);
if (conn && conn->status != CONNECTION_BAD)
(void) connectDBComplete(conn);
return conn;
}
/*
* PQpingParams
*
* check server status, accepting parameters identical to PQconnectdbParams
*/
PGPing
PQpingParams(const char *const *keywords,
const char *const *values,
int expand_dbname)
{
PGconn *conn = PQconnectStartParams(keywords, values, expand_dbname);
PGPing ret;
ret = internal_ping(conn);
PQfinish(conn);
return ret;
}
/*
* PQconnectdb
*
* establishes a connection to a postgres backend through the postmaster
* using connection information in a string.
*
* The conninfo string is either a whitespace-separated list of
*
* option = value
*
* definitions or a URI (refer to the documentation for details.) Value
* might be a single value containing no whitespaces or a single quoted
* string. If a single quote should appear anywhere in the value, it must be
* escaped with a backslash like \'
*
* Returns a PGconn* which is needed for all subsequent libpq calls, or NULL
* if a memory allocation failed.
* If the status field of the connection returned is CONNECTION_BAD,
* then some fields may be null'ed out instead of having valid values.
*
* You should call PQfinish (if conn is not NULL) regardless of whether this
* call succeeded.
*/
PGconn *
PQconnectdb(const char *conninfo)
{
PGconn *conn = PQconnectStart(conninfo);
if (conn && conn->status != CONNECTION_BAD)
(void) connectDBComplete(conn);
return conn;
}
/*
* PQping
*
* check server status, accepting parameters identical to PQconnectdb
*/
PGPing
PQping(const char *conninfo)
{
PGconn *conn = PQconnectStart(conninfo);
PGPing ret;
ret = internal_ping(conn);
PQfinish(conn);
return ret;
}
/*
* PQconnectStartParams
*
* Begins the establishment of a connection to a postgres backend through the
* postmaster using connection information in a struct.
*
* See comment for PQconnectdbParams for the definition of the string format.
*
* Returns a PGconn*. If NULL is returned, a malloc error has occurred, and
* you should not attempt to proceed with this connection. If the status
* field of the connection returned is CONNECTION_BAD, an error has
* occurred. In this case you should call PQfinish on the result, (perhaps
* inspecting the error message first). Other fields of the structure may not
* be valid if that occurs. If the status field is not CONNECTION_BAD, then
* this stage has succeeded - call PQconnectPoll, using select(2) to see when
* this is necessary.
*
* See PQconnectPoll for more info.
*/
PGconn *
PQconnectStartParams(const char *const *keywords,
const char *const *values,
int expand_dbname)
{
PGconn *conn;
PQconninfoOption *connOptions;
/*
* Allocate memory for the conn structure
*/
conn = makeEmptyPGconn();
if (conn == NULL)
return NULL;
/*
* Parse the conninfo arrays
*/
connOptions = conninfo_array_parse(keywords, values,
&conn->errorMessage,
true, expand_dbname);
if (connOptions == NULL)
{
conn->status = CONNECTION_BAD;
/* errorMessage is already set */
return conn;
}
/*
* Move option values into conn structure
*/
if (!fillPGconn(conn, connOptions))
{
PQconninfoFree(connOptions);
return conn;
}
/*
* Free the option info - all is in conn now
*/
PQconninfoFree(connOptions);
/*
* Compute derived options
*/
if (!connectOptions2(conn))
return conn;
/*
* Connect to the database
*/
if (!connectDBStart(conn))
{
/* Just in case we failed to set it in connectDBStart */
conn->status = CONNECTION_BAD;
}
return conn;
}
/*
* PQconnectStart
*
* Begins the establishment of a connection to a postgres backend through the
* postmaster using connection information in a string.
*
* See comment for PQconnectdb for the definition of the string format.
*
* Returns a PGconn*. If NULL is returned, a malloc error has occurred, and
* you should not attempt to proceed with this connection. If the status
* field of the connection returned is CONNECTION_BAD, an error has
* occurred. In this case you should call PQfinish on the result, (perhaps
* inspecting the error message first). Other fields of the structure may not
* be valid if that occurs. If the status field is not CONNECTION_BAD, then
* this stage has succeeded - call PQconnectPoll, using select(2) to see when
* this is necessary.
*
* See PQconnectPoll for more info.
*/
PGconn *
PQconnectStart(const char *conninfo)
{
PGconn *conn;
/*
* Allocate memory for the conn structure
*/
conn = makeEmptyPGconn();
if (conn == NULL)
return NULL;
/*
* Parse the conninfo string
*/
if (!connectOptions1(conn, conninfo))
return conn;
/*
* Compute derived options
*/
if (!connectOptions2(conn))
return conn;
/*
* Connect to the database
*/
if (!connectDBStart(conn))
{
/* Just in case we failed to set it in connectDBStart */
conn->status = CONNECTION_BAD;
}
return conn;
}
/*
* Move option values into conn structure
*
* Don't put anything cute here --- intelligence should be in
* connectOptions2 ...
*
* Returns true on success. On failure, returns false and sets error message.
*/
static bool
fillPGconn(PGconn *conn, PQconninfoOption *connOptions)
{
const internalPQconninfoOption *option;
for (option = PQconninfoOptions; option->keyword; option++)
{
if (option->connofs >= 0)
{
const char *tmp = conninfo_getval(connOptions, option->keyword);
if (tmp)
{
char **connmember = (char **) ((char *) conn + option->connofs);
if (*connmember)
free(*connmember);
*connmember = strdup(tmp);
if (*connmember == NULL)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
}
}
}
return true;
}
/*
* connectOptions1
*
* Internal subroutine to set up connection parameters given an already-
* created PGconn and a conninfo string. Derived settings should be
* processed by calling connectOptions2 next. (We split them because
* PQsetdbLogin overrides defaults in between.)
*
* Returns true if OK, false if trouble (in which case errorMessage is set
* and so is conn->status).
*/
static bool
connectOptions1(PGconn *conn, const char *conninfo)
{
PQconninfoOption *connOptions;
/*
* Parse the conninfo string
*/
connOptions = parse_connection_string(conninfo, &conn->errorMessage, true);
if (connOptions == NULL)
{
conn->status = CONNECTION_BAD;
/* errorMessage is already set */
return false;
}
/*
* Move option values into conn structure
*/
if (!fillPGconn(conn, connOptions))
{
conn->status = CONNECTION_BAD;
PQconninfoFree(connOptions);
return false;
}
/*
* Free the option info - all is in conn now
*/
PQconninfoFree(connOptions);
return true;
}
/*
* Count the number of elements in a simple comma-separated list.
*/
static int
count_comma_separated_elems(const char *input)
{
int n;
n = 1;
for (; *input != '\0'; input++)
{
if (*input == ',')
n++;
}
return n;
}
/*
* Parse a simple comma-separated list.
*
* On each call, returns a malloc'd copy of the next element, and sets *more
* to indicate whether there are any more elements in the list after this,
* and updates *startptr to point to the next element, if any.
*
* On out of memory, returns NULL.
*/
static char *
parse_comma_separated_list(char **startptr, bool *more)
{
char *p;
char *s = *startptr;
char *e;
int len;
/*
* Search for the end of the current element; a comma or end-of-string
* acts as a terminator.
*/
e = s;
while (*e != '\0' && *e != ',')
++e;
*more = (*e == ',');
len = e - s;
p = (char *) malloc(sizeof(char) * (len + 1));
if (p)
{
memcpy(p, s, len);
p[len] = '\0';
}
*startptr = e + 1;
return p;
}
/*
* connectOptions2
*
* Compute derived connection options after absorbing all user-supplied info.
*
* Returns true if OK, false if trouble (in which case errorMessage is set
* and so is conn->status).
*/
static bool
connectOptions2(PGconn *conn)
{
int i;
/*
* Allocate memory for details about each host to which we might possibly
* try to connect. For that, count the number of elements in the hostaddr
* or host options. If neither is given, assume one host.
*/
conn->whichhost = 0;
if (conn->pghostaddr && conn->pghostaddr[0] != '\0')
conn->nconnhost = count_comma_separated_elems(conn->pghostaddr);
else if (conn->pghost && conn->pghost[0] != '\0')
conn->nconnhost = count_comma_separated_elems(conn->pghost);
else
conn->nconnhost = 1;
conn->connhost = (pg_conn_host *)
calloc(conn->nconnhost, sizeof(pg_conn_host));
if (conn->connhost == NULL)
goto oom_error;
/*
* We now have one pg_conn_host structure per possible host. Fill in the
* host and hostaddr fields for each, by splitting the parameter strings.
*/
if (conn->pghostaddr != NULL && conn->pghostaddr[0] != '\0')
{
char *s = conn->pghostaddr;
bool more = true;
for (i = 0; i < conn->nconnhost && more; i++)
{
conn->connhost[i].hostaddr = parse_comma_separated_list(&s, &more);
if (conn->connhost[i].hostaddr == NULL)
goto oom_error;
}
/*
* If hostaddr was given, the array was allocated according to the
* number of elements in the hostaddr list, so it really should be the
* right size.
*/
Assert(!more);
Assert(i == conn->nconnhost);
}
if (conn->pghost != NULL && conn->pghost[0] != '\0')
{
char *s = conn->pghost;
bool more = true;
for (i = 0; i < conn->nconnhost && more; i++)
{
conn->connhost[i].host = parse_comma_separated_list(&s, &more);
if (conn->connhost[i].host == NULL)
goto oom_error;
}
/* Check for wrong number of host items. */
if (more || i != conn->nconnhost)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not match %d host names to %d hostaddr values\n"),
count_comma_separated_elems(conn->pghost), conn->nconnhost);
return false;
}
}
/*
* Now, for each host slot, identify the type of address spec, and fill in
* the default address if nothing was given.
*/
for (i = 0; i < conn->nconnhost; i++)
{
pg_conn_host *ch = &conn->connhost[i];
if (ch->hostaddr != NULL && ch->hostaddr[0] != '\0')
ch->type = CHT_HOST_ADDRESS;
else if (ch->host != NULL && ch->host[0] != '\0')
{
ch->type = CHT_HOST_NAME;
#ifdef HAVE_UNIX_SOCKETS
if (is_absolute_path(ch->host))
ch->type = CHT_UNIX_SOCKET;
#endif
}
else
{
if (ch->host)
free(ch->host);
#ifdef HAVE_UNIX_SOCKETS
ch->host = strdup(DEFAULT_PGSOCKET_DIR);
ch->type = CHT_UNIX_SOCKET;
#else
ch->host = strdup(DefaultHost);
ch->type = CHT_HOST_NAME;
#endif
if (ch->host == NULL)
goto oom_error;
}
}
/*
* Next, work out the port number corresponding to each host name.
*
* Note: unlike the above for host names, this could leave the port fields
* as null or empty strings. We will substitute DEF_PGPORT whenever we
* read such a port field.
*/
if (conn->pgport != NULL && conn->pgport[0] != '\0')
{
char *s = conn->pgport;
bool more = true;
for (i = 0; i < conn->nconnhost && more; i++)
{
conn->connhost[i].port = parse_comma_separated_list(&s, &more);
if (conn->connhost[i].port == NULL)
goto oom_error;
}
/*
* If exactly one port was given, use it for every host. Otherwise,
* there must be exactly as many ports as there were hosts.
*/
if (i == 1 && !more)
{
for (i = 1; i < conn->nconnhost; i++)
{
conn->connhost[i].port = strdup(conn->connhost[0].port);
if (conn->connhost[i].port == NULL)
goto oom_error;
}
}
else if (more || i != conn->nconnhost)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not match %d port numbers to %d hosts\n"),
count_comma_separated_elems(conn->pgport), conn->nconnhost);
return false;
}
}
/*
* If user name was not given, fetch it. (Most likely, the fetch will
* fail, since the only way we get here is if pg_fe_getauthname() failed
* during conninfo_add_defaults(). But now we want an error message.)
*/
if (conn->pguser == NULL || conn->pguser[0] == '\0')
{
if (conn->pguser)
free(conn->pguser);
conn->pguser = pg_fe_getauthname(&conn->errorMessage);
if (!conn->pguser)
{
conn->status = CONNECTION_BAD;
return false;
}
}
/*
* If database name was not given, default it to equal user name
*/
if (conn->dbName == NULL || conn->dbName[0] == '\0')
{
if (conn->dbName)
free(conn->dbName);
conn->dbName = strdup(conn->pguser);
if (!conn->dbName)
goto oom_error;
}
/*
* If password was not given, try to look it up in password file. Note
* that the result might be different for each host/port pair.
*/
if (conn->pgpass == NULL || conn->pgpass[0] == '\0')
{
/* If password file wasn't specified, use ~/PGPASSFILE */
if (conn->pgpassfile == NULL || conn->pgpassfile[0] == '\0')
{
char homedir[MAXPGPATH];
if (pqGetHomeDirectory(homedir, sizeof(homedir)))
{
if (conn->pgpassfile)
free(conn->pgpassfile);
conn->pgpassfile = malloc(MAXPGPATH);
if (!conn->pgpassfile)
goto oom_error;
snprintf(conn->pgpassfile, MAXPGPATH, "%s/%s",
homedir, PGPASSFILE);
}
}
if (conn->pgpassfile != NULL && conn->pgpassfile[0] != '\0')
{
for (i = 0; i < conn->nconnhost; i++)
{
/*
* Try to get a password for this host from file. We use host
* for the hostname search key if given, else hostaddr (at
* least one of them is guaranteed nonempty by now).
*/
const char *pwhost = conn->connhost[i].host;
if (pwhost == NULL || pwhost[0] == '\0')
pwhost = conn->connhost[i].hostaddr;
conn->connhost[i].password =
passwordFromFile(pwhost,
conn->connhost[i].port,
conn->dbName,
conn->pguser,
conn->pgpassfile);
}
}
}
/*
* validate channel_binding option
*/
if (conn->channel_binding)
{
if (strcmp(conn->channel_binding, "disable") != 0
&& strcmp(conn->channel_binding, "prefer") != 0
&& strcmp(conn->channel_binding, "require") != 0)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid channel_binding value: \"%s\"\n"),
conn->channel_binding);
return false;
}
}
else
{
conn->channel_binding = strdup(DefaultChannelBinding);
if (!conn->channel_binding)
goto oom_error;
}
/*
* validate sslmode option
*/
if (conn->sslmode)
{
if (strcmp(conn->sslmode, "disable") != 0
&& strcmp(conn->sslmode, "allow") != 0
&& strcmp(conn->sslmode, "prefer") != 0
&& strcmp(conn->sslmode, "require") != 0
&& strcmp(conn->sslmode, "verify-ca") != 0
&& strcmp(conn->sslmode, "verify-full") != 0)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid sslmode value: \"%s\"\n"),
conn->sslmode);
return false;
}
#ifndef USE_SSL
switch (conn->sslmode[0])
{
case 'a': /* "allow" */
case 'p': /* "prefer" */
/*
* warn user that an SSL connection will never be negotiated
* since SSL was not compiled in?
*/
break;
case 'r': /* "require" */
case 'v': /* "verify-ca" or "verify-full" */
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("sslmode value \"%s\" invalid when SSL support is not compiled in\n"),
conn->sslmode);
return false;
}
#endif
}
else
{
conn->sslmode = strdup(DefaultSSLMode);
if (!conn->sslmode)
goto oom_error;
}
/*
* Validate TLS protocol versions for sslminprotocolversion and
* sslmaxprotocolversion.
*/
if (!sslVerifyProtocolVersion(conn->sslminprotocolversion))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid sslminprotocolversion value: \"%s\"\n"),
conn->sslminprotocolversion);
return false;
}
if (!sslVerifyProtocolVersion(conn->sslmaxprotocolversion))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid sslmaxprotocolversion value: \"%s\"\n"),
conn->sslmaxprotocolversion);
return false;
}
/*
* Check if the range of SSL protocols defined is correct. This is done
* at this early step because this is independent of the SSL
* implementation used, and this avoids unnecessary cycles with an
* already-built SSL context when the connection is being established, as
* it would be doomed anyway.
*/
if (!sslVerifyProtocolRange(conn->sslminprotocolversion,
conn->sslmaxprotocolversion))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid SSL protocol version range"));
return false;
}
/*
* validate gssencmode option
*/
if (conn->gssencmode)
{
if (strcmp(conn->gssencmode, "disable") != 0 &&
strcmp(conn->gssencmode, "prefer") != 0 &&
strcmp(conn->gssencmode, "require") != 0)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid gssencmode value: \"%s\"\n"),
conn->gssencmode);
return false;
}
#ifndef ENABLE_GSS
if (strcmp(conn->gssencmode, "require") == 0)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("gssencmode value \"%s\" invalid when GSSAPI support is not compiled in\n"),
conn->gssencmode);
return false;
}
#endif
}
else
{
conn->gssencmode = strdup(DefaultGSSMode);
if (!conn->gssencmode)
goto oom_error;
}
/*
* Resolve special "auto" client_encoding from the locale
*/
if (conn->client_encoding_initial &&
strcmp(conn->client_encoding_initial, "auto") == 0)
{
free(conn->client_encoding_initial);
conn->client_encoding_initial = strdup(pg_encoding_to_char(pg_get_encoding_from_locale(NULL, true)));
if (!conn->client_encoding_initial)
goto oom_error;
}
/*
* Validate target_session_attrs option.
*/
if (conn->target_session_attrs)
{
if (strcmp(conn->target_session_attrs, "any") != 0
&& strcmp(conn->target_session_attrs, "read-write") != 0)
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid target_session_attrs value: \"%s\"\n"),
conn->target_session_attrs);
return false;
}
}
/*
* Only if we get this far is it appropriate to try to connect. (We need a
* state flag, rather than just the boolean result of this function, in
* case someone tries to PQreset() the PGconn.)
*/
conn->options_valid = true;
return true;
oom_error:
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
/*
* PQconndefaults
*
* Construct a default connection options array, which identifies all the
* available options and shows any default values that are available from the
* environment etc. On error (eg out of memory), NULL is returned.
*
* Using this function, an application may determine all possible options
* and their current default values.
*
* NOTE: as of PostgreSQL 7.0, the returned array is dynamically allocated
* and should be freed when no longer needed via PQconninfoFree(). (In prior
* versions, the returned array was static, but that's not thread-safe.)
* Pre-7.0 applications that use this function will see a small memory leak
* until they are updated to call PQconninfoFree.
*/
PQconninfoOption *
PQconndefaults(void)
{
PQExpBufferData errorBuf;
PQconninfoOption *connOptions;
/* We don't actually report any errors here, but callees want a buffer */
initPQExpBuffer(&errorBuf);
if (PQExpBufferDataBroken(errorBuf))
return NULL; /* out of memory already :-( */
connOptions = conninfo_init(&errorBuf);
if (connOptions != NULL)
{
/* pass NULL errorBuf to ignore errors */
if (!conninfo_add_defaults(connOptions, NULL))
{
PQconninfoFree(connOptions);
connOptions = NULL;
}
}
termPQExpBuffer(&errorBuf);
return connOptions;
}
/* ----------------
* PQsetdbLogin
*
* establishes a connection to a postgres backend through the postmaster
* at the specified host and port.
*
* returns a PGconn* which is needed for all subsequent libpq calls
*
* if the status field of the connection returned is CONNECTION_BAD,
* then only the errorMessage is likely to be useful.
* ----------------
*/
PGconn *
PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
const char *pgtty, const char *dbName, const char *login,
const char *pwd)
{
PGconn *conn;
/*
* Allocate memory for the conn structure
*/
conn = makeEmptyPGconn();
if (conn == NULL)
return NULL;
/*
* If the dbName parameter contains what looks like a connection string,
* parse it into conn struct using connectOptions1.
*/
if (dbName && recognized_connection_string(dbName))
{
if (!connectOptions1(conn, dbName))
return conn;
}
else
{
/*
* Old-style path: first, parse an empty conninfo string in order to
* set up the same defaults that PQconnectdb() would use.
*/
if (!connectOptions1(conn, ""))
return conn;
/* Insert dbName parameter value into struct */
if (dbName && dbName[0] != '\0')
{
if (conn->dbName)
free(conn->dbName);
conn->dbName = strdup(dbName);
if (!conn->dbName)
goto oom_error;
}
}
/*
* Insert remaining parameters into struct, overriding defaults (as well
* as any conflicting data from dbName taken as a conninfo).
*/
if (pghost && pghost[0] != '\0')
{
if (conn->pghost)
free(conn->pghost);
conn->pghost = strdup(pghost);
if (!conn->pghost)
goto oom_error;
}
if (pgport && pgport[0] != '\0')
{
if (conn->pgport)
free(conn->pgport);
conn->pgport = strdup(pgport);
if (!conn->pgport)
goto oom_error;
}
if (pgoptions && pgoptions[0] != '\0')
{
if (conn->pgoptions)
free(conn->pgoptions);
conn->pgoptions = strdup(pgoptions);
if (!conn->pgoptions)
goto oom_error;
}
if (pgtty && pgtty[0] != '\0')
{
if (conn->pgtty)
free(conn->pgtty);
conn->pgtty = strdup(pgtty);
if (!conn->pgtty)
goto oom_error;
}
if (login && login[0] != '\0')
{
if (conn->pguser)
free(conn->pguser);
conn->pguser = strdup(login);
if (!conn->pguser)
goto oom_error;
}
if (pwd && pwd[0] != '\0')
{
if (conn->pgpass)
free(conn->pgpass);
conn->pgpass = strdup(pwd);
if (!conn->pgpass)
goto oom_error;
}
/*
* Compute derived options
*/
if (!connectOptions2(conn))
return conn;
/*
* Connect to the database
*/
if (connectDBStart(conn))
(void) connectDBComplete(conn);
return conn;
oom_error:
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return conn;
}
/* ----------
* connectNoDelay -
* Sets the TCP_NODELAY socket option.
* Returns 1 if successful, 0 if not.
* ----------
*/
static int
connectNoDelay(PGconn *conn)
{
#ifdef TCP_NODELAY
int on = 1;
if (setsockopt(conn->sock, IPPROTO_TCP, TCP_NODELAY,
(char *) &on,
sizeof(on)) < 0)
{
char sebuf[PG_STRERROR_R_BUFLEN];
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not set socket to TCP no delay mode: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
return 0;
}
#endif
return 1;
}
/* ----------
* Write currently connected IP address into host_addr (of len host_addr_len).
* If unable to, set it to the empty string.
* ----------
*/
static void
getHostaddr(PGconn *conn, char *host_addr, int host_addr_len)
{
struct sockaddr_storage *addr = &conn->raddr.addr;
if (addr->ss_family == AF_INET)
{
if (pg_inet_net_ntop(AF_INET,
&((struct sockaddr_in *) addr)->sin_addr.s_addr,
32,
host_addr, host_addr_len) == NULL)
host_addr[0] = '\0';
}
#ifdef HAVE_IPV6
else if (addr->ss_family == AF_INET6)
{
if (pg_inet_net_ntop(AF_INET6,
&((struct sockaddr_in6 *) addr)->sin6_addr.s6_addr,
128,
host_addr, host_addr_len) == NULL)
host_addr[0] = '\0';
}
#endif
else
host_addr[0] = '\0';
}
/* ----------
* connectFailureMessage -
* create a friendly error message on connection failure.
* ----------
*/
static void
connectFailureMessage(PGconn *conn, int errorno)
{
char sebuf[PG_STRERROR_R_BUFLEN];
#ifdef HAVE_UNIX_SOCKETS
if (IS_AF_UNIX(conn->raddr.addr.ss_family))
{
char service[NI_MAXHOST];
pg_getnameinfo_all(&conn->raddr.addr, conn->raddr.salen,
NULL, 0,
service, sizeof(service),
NI_NUMERICSERV);
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not connect to server: %s\n"
"\tIs the server running locally and accepting\n"
"\tconnections on Unix domain socket \"%s\"?\n"),
SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)),
service);
}
else
#endif /* HAVE_UNIX_SOCKETS */
{
char host_addr[NI_MAXHOST];
const char *displayed_host;
const char *displayed_port;
/*
* Optionally display the network address with the hostname. This is
* useful to distinguish between IPv4 and IPv6 connections.
*/
getHostaddr(conn, host_addr, NI_MAXHOST);
/* To which host and port were we actually connecting? */
if (conn->connhost[conn->whichhost].type == CHT_HOST_ADDRESS)
displayed_host = conn->connhost[conn->whichhost].hostaddr;
else
displayed_host = conn->connhost[conn->whichhost].host;
displayed_port = conn->connhost[conn->whichhost].port;
if (displayed_port == NULL || displayed_port[0] == '\0')
displayed_port = DEF_PGPORT_STR;
/*
* If the user did not supply an IP address using 'hostaddr', and
* 'host' was missing or does not match our lookup, display the
* looked-up IP address.
*/
if (conn->connhost[conn->whichhost].type != CHT_HOST_ADDRESS &&
strlen(host_addr) > 0 &&
strcmp(displayed_host, host_addr) != 0)
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not connect to server: %s\n"
"\tIs the server running on host \"%s\" (%s) and accepting\n"
"\tTCP/IP connections on port %s?\n"),
SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)),
displayed_host, host_addr,
displayed_port);
else
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not connect to server: %s\n"
"\tIs the server running on host \"%s\" and accepting\n"
"\tTCP/IP connections on port %s?\n"),
SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)),
displayed_host,
displayed_port);
}
}
/*
* Should we use keepalives? Returns 1 if yes, 0 if no, and -1 if
* conn->keepalives is set to a value which is not parseable as an
* integer.
*/
static int
useKeepalives(PGconn *conn)
{
char *ep;
int val;
if (conn->keepalives == NULL)
return 1;
val = strtol(conn->keepalives, &ep, 10);
if (*ep)
return -1;
return val != 0 ? 1 : 0;
}
/*
* Parse and try to interpret "value" as an integer value, and if successful,
* store it in *result, complaining if there is any trailing garbage or an
* overflow. This allows any number of leading and trailing whitespaces.
*/
static bool
parse_int_param(const char *value, int *result, PGconn *conn,
const char *context)
{
char *end;
long numval;
Assert(value != NULL);
*result = 0;
/* strtol(3) skips leading whitespaces */
errno = 0;
numval = strtol(value, &end, 10);
/*
* If no progress was done during the parsing or an error happened, fail.
* This tests properly for overflows of the result.
*/
if (value == end || errno != 0 || numval != (int) numval)
goto error;
/*
* Skip any trailing whitespace; if anything but whitespace remains before
* the terminating character, fail
*/
while (*end != '\0' && isspace((unsigned char) *end))
end++;
if (*end != '\0')
goto error;
*result = numval;
return true;
error:
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid integer value \"%s\" for connection option \"%s\"\n"),
value, context);
return false;
}
#ifndef WIN32
/*
* Set the keepalive idle timer.
*/
static int
setKeepalivesIdle(PGconn *conn)
{
int idle;
if (conn->keepalives_idle == NULL)
return 1;
if (!parse_int_param(conn->keepalives_idle, &idle, conn,
"keepalives_idle"))
return 0;
if (idle < 0)
idle = 0;
#ifdef PG_TCP_KEEPALIVE_IDLE
if (setsockopt(conn->sock, IPPROTO_TCP, PG_TCP_KEEPALIVE_IDLE,
(char *) &idle, sizeof(idle)) < 0)
{
char sebuf[PG_STRERROR_R_BUFLEN];
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("setsockopt(%s) failed: %s\n"),
PG_TCP_KEEPALIVE_IDLE_STR,
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
return 0;
}
#endif
return 1;
}
/*
* Set the keepalive interval.
*/
static int
setKeepalivesInterval(PGconn *conn)
{
int interval;
if (conn->keepalives_interval == NULL)
return 1;
if (!parse_int_param(conn->keepalives_interval, &interval, conn,
"keepalives_interval"))
return 0;
if (interval < 0)
interval = 0;
#ifdef TCP_KEEPINTVL
if (setsockopt(conn->sock, IPPROTO_TCP, TCP_KEEPINTVL,
(char *) &interval, sizeof(interval)) < 0)
{
char sebuf[PG_STRERROR_R_BUFLEN];
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("setsockopt(%s) failed: %s\n"),
"TCP_KEEPINTVL",
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
return 0;
}
#endif
return 1;
}
/*
* Set the count of lost keepalive packets that will trigger a connection
* break.
*/
static int
setKeepalivesCount(PGconn *conn)
{
int count;
if (conn->keepalives_count == NULL)
return 1;
if (!parse_int_param(conn->keepalives_count, &count, conn,
"keepalives_count"))
return 0;
if (count < 0)
count = 0;
#ifdef TCP_KEEPCNT
if (setsockopt(conn->sock, IPPROTO_TCP, TCP_KEEPCNT,
(char *) &count, sizeof(count)) < 0)
{
char sebuf[PG_STRERROR_R_BUFLEN];
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("setsockopt(%s) failed: %s\n"),
"TCP_KEEPCNT",
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
return 0;
}
#endif
return 1;
}
#else /* WIN32 */
#ifdef SIO_KEEPALIVE_VALS
/*
* Enable keepalives and set the keepalive values on Win32,
* where they are always set in one batch.
*/
static int
setKeepalivesWin32(PGconn *conn)
{
struct tcp_keepalive ka;
DWORD retsize;
int idle = 0;
int interval = 0;
if (conn->keepalives_idle &&
!parse_int_param(conn->keepalives_idle, &idle, conn,
"keepalives_idle"))
return 0;
if (idle <= 0)
idle = 2 * 60 * 60; /* 2 hours = default */
if (conn->keepalives_interval &&
!parse_int_param(conn->keepalives_interval, &interval, conn,
"keepalives_interval"))
return 0;
if (interval <= 0)
interval = 1; /* 1 second = default */
ka.onoff = 1;
ka.keepalivetime = idle * 1000;
ka.keepaliveinterval = interval * 1000;
if (WSAIoctl(conn->sock,
SIO_KEEPALIVE_VALS,
(LPVOID) &ka,
sizeof(ka),
NULL,
0,
&retsize,
NULL,
NULL)
!= 0)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("WSAIoctl(SIO_KEEPALIVE_VALS) failed: %ui\n"),
WSAGetLastError());
return 0;
}
return 1;
}
#endif /* SIO_KEEPALIVE_VALS */
#endif /* WIN32 */
/*
* Set the TCP user timeout.
*/
static int
setTCPUserTimeout(PGconn *conn)
{
int timeout;
if (conn->pgtcp_user_timeout == NULL)
return 1;
if (!parse_int_param(conn->pgtcp_user_timeout, &timeout, conn,
"tcp_user_timeout"))
return 0;
if (timeout < 0)
timeout = 0;
#ifdef TCP_USER_TIMEOUT
if (setsockopt(conn->sock, IPPROTO_TCP, TCP_USER_TIMEOUT,
(char *) &timeout, sizeof(timeout)) < 0)
{
char sebuf[256];
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("setsockopt(%s) failed: %s\n"),
"TCP_USER_TIMEOUT",
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
return 0;
}
#endif
return 1;
}
/* ----------
* connectDBStart -
* Begin the process of making a connection to the backend.
*
* Returns 1 if successful, 0 if not.
* ----------
*/
static int
connectDBStart(PGconn *conn)
{
if (!conn)
return 0;
if (!conn->options_valid)
goto connect_errReturn;
/*
* Check for bad linking to backend-internal versions of src/common
* functions (see comments in link-canary.c for the reason we need this).
* Nobody but developers should see this message, so we don't bother
* translating it.
*/
if (!pg_link_canary_is_frontend())
{
printfPQExpBuffer(&conn->errorMessage,
"libpq is incorrectly linked to backend functions\n");
goto connect_errReturn;
}
/* Ensure our buffers are empty */
conn->inStart = conn->inCursor = conn->inEnd = 0;
conn->outCount = 0;
/*
* Ensure errorMessage is empty, too. PQconnectPoll will append messages
* to it in the process of scanning for a working server. Thus, if we
* fail to connect to multiple hosts, the final error message will include
* details about each failure.
*/
resetPQExpBuffer(&conn->errorMessage);
#ifdef ENABLE_GSS
if (conn->gssencmode[0] == 'd') /* "disable" */
conn->try_gss = false;
#endif
/*
* Set up to try to connect to the first host. (Setting whichhost = -1 is
* a bit of a cheat, but PQconnectPoll will advance it to 0 before
* anything else looks at it.)
*/
conn->whichhost = -1;
conn->try_next_addr = false;
conn->try_next_host = true;
conn->status = CONNECTION_NEEDED;
/*
* The code for processing CONNECTION_NEEDED state is in PQconnectPoll(),
* so that it can easily be re-executed if needed again during the
* asynchronous startup process. However, we must run it once here,
* because callers expect a success return from this routine to mean that
* we are in PGRES_POLLING_WRITING connection state.
*/
if (PQconnectPoll(conn) == PGRES_POLLING_WRITING)
return 1;
connect_errReturn:
/*
* If we managed to open a socket, close it immediately rather than
* waiting till PQfinish. (The application cannot have gotten the socket
* from PQsocket yet, so this doesn't risk breaking anything.)
*/
pqDropConnection(conn, true);
conn->status = CONNECTION_BAD;
return 0;
}
/*
* connectDBComplete
*
* Block and complete a connection.
*
* Returns 1 on success, 0 on failure.
*/
static int
connectDBComplete(PGconn *conn)
{
PostgresPollingStatusType flag = PGRES_POLLING_WRITING;
time_t finish_time = ((time_t) -1);
int timeout = 0;
int last_whichhost = -2; /* certainly different from whichhost */
struct addrinfo *last_addr_cur = NULL;
if (conn == NULL || conn->status == CONNECTION_BAD)
return 0;
/*
* Set up a time limit, if connect_timeout isn't zero.
*/
if (conn->connect_timeout != NULL)
{
if (!parse_int_param(conn->connect_timeout, &timeout, conn,
"connect_timeout"))
{
/* mark the connection as bad to report the parsing failure */
conn->status = CONNECTION_BAD;
return 0;
}
if (timeout > 0)
{
/*
* Rounding could cause connection to fail unexpectedly quickly;
* to prevent possibly waiting hardly-at-all, insist on at least
* two seconds.
*/
if (timeout < 2)
timeout = 2;
}
else /* negative means 0 */
timeout = 0;
}
for (;;)
{
int ret = 0;
/*
* (Re)start the connect_timeout timer if it's active and we are
* considering a different host than we were last time through. If
* we've already succeeded, though, needn't recalculate.
*/
if (flag != PGRES_POLLING_OK &&
timeout > 0 &&
(conn->whichhost != last_whichhost ||
conn->addr_cur != last_addr_cur))
{
finish_time = time(NULL) + timeout;
last_whichhost = conn->whichhost;
last_addr_cur = conn->addr_cur;
}
/*
* Wait, if necessary. Note that the initial state (just after
* PQconnectStart) is to wait for the socket to select for writing.
*/
switch (flag)
{
case PGRES_POLLING_OK:
/*
* Reset stored error messages since we now have a working
* connection
*/
resetPQExpBuffer(&conn->errorMessage);
return 1; /* success! */
case PGRES_POLLING_READING:
ret = pqWaitTimed(1, 0, conn, finish_time);
if (ret == -1)
{
/* hard failure, eg select() problem, aborts everything */
conn->status = CONNECTION_BAD;
return 0;
}
break;
case PGRES_POLLING_WRITING:
ret = pqWaitTimed(0, 1, conn, finish_time);
if (ret == -1)
{
/* hard failure, eg select() problem, aborts everything */
conn->status = CONNECTION_BAD;
return 0;
}
break;
default:
/* Just in case we failed to set it in PQconnectPoll */
conn->status = CONNECTION_BAD;
return 0;
}
if (ret == 1) /* connect_timeout elapsed */
{
/*
* Give up on current server/address, try the next one.
*/
conn->try_next_addr = true;
conn->status = CONNECTION_NEEDED;
}
/*
* Now try to advance the state machine.
*/
flag = PQconnectPoll(conn);
}
}
/*
* This subroutine saves conn->errorMessage, which will be restored back by
* restoreErrorMessage subroutine. Returns false on OOM failure.
*/
static bool
saveErrorMessage(PGconn *conn, PQExpBuffer savedMessage)
{
initPQExpBuffer(savedMessage);
appendPQExpBufferStr(savedMessage,
conn->errorMessage.data);
if (PQExpBufferBroken(savedMessage))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
/* Clear whatever is in errorMessage now */
resetPQExpBuffer(&conn->errorMessage);
return true;
}
/*
* Restores saved error messages back to conn->errorMessage, prepending them
* to whatever is in conn->errorMessage already. (This does the right thing
* if anything's been added to conn->errorMessage since saveErrorMessage.)
*/
static void
restoreErrorMessage(PGconn *conn, PQExpBuffer savedMessage)
{
appendPQExpBufferStr(savedMessage, conn->errorMessage.data);
resetPQExpBuffer(&conn->errorMessage);
appendPQExpBufferStr(&conn->errorMessage, savedMessage->data);
/* If any step above hit OOM, just report that */
if (PQExpBufferBroken(savedMessage) ||
PQExpBufferBroken(&conn->errorMessage))
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
termPQExpBuffer(savedMessage);
}
/* ----------------
* PQconnectPoll
*
* Poll an asynchronous connection.
*
* Returns a PostgresPollingStatusType.
* Before calling this function, use select(2) to determine when data
* has arrived..
*
* You must call PQfinish whether or not this fails.
*
* This function and PQconnectStart are intended to allow connections to be
* made without blocking the execution of your program on remote I/O. However,
* there are a number of caveats:
*
* o If you call PQtrace, ensure that the stream object into which you trace
* will not block.
* o If you do not supply an IP address for the remote host (i.e. you
* supply a host name instead) then PQconnectStart will block on
* gethostbyname. You will be fine if using Unix sockets (i.e. by
* supplying neither a host name nor a host address).
* o If your backend wants to use Kerberos authentication then you must
* supply both a host name and a host address, otherwise this function
* may block on gethostname.
*
* ----------------
*/
PostgresPollingStatusType
PQconnectPoll(PGconn *conn)
{
bool reset_connection_state_machine = false;
bool need_new_connection = false;
PGresult *res;
char sebuf[PG_STRERROR_R_BUFLEN];
int optval;
PQExpBufferData savedMessage;
if (conn == NULL)
return PGRES_POLLING_FAILED;
/* Get the new data */
switch (conn->status)
{
/*
* We really shouldn't have been polled in these two cases, but we
* can handle it.
*/
case CONNECTION_BAD:
return PGRES_POLLING_FAILED;
case CONNECTION_OK:
return PGRES_POLLING_OK;
/* These are reading states */
case CONNECTION_AWAITING_RESPONSE:
case CONNECTION_AUTH_OK:
{
/* Load waiting data */
int n = pqReadData(conn);
if (n < 0)
goto error_return;
if (n == 0)
return PGRES_POLLING_READING;
break;
}
/* These are writing states, so we just proceed. */
case CONNECTION_STARTED:
case CONNECTION_MADE:
break;
/* We allow pqSetenvPoll to decide whether to proceed. */
case CONNECTION_SETENV:
break;
/* Special cases: proceed without waiting. */
case CONNECTION_SSL_STARTUP:
case CONNECTION_NEEDED:
case CONNECTION_CHECK_WRITABLE:
case CONNECTION_CONSUME:
case CONNECTION_GSS_STARTUP:
break;
default:
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext(
"invalid connection state, "
"probably indicative of memory corruption\n"
));
goto error_return;
}
keep_going: /* We will come back to here until there is
* nothing left to do. */
/* Time to advance to next address, or next host if no more addresses? */
if (conn->try_next_addr)
{
if (conn->addr_cur && conn->addr_cur->ai_next)
{
conn->addr_cur = conn->addr_cur->ai_next;
reset_connection_state_machine = true;
}
else
conn->try_next_host = true;
conn->try_next_addr = false;
}
/* Time to advance to next connhost[] entry? */
if (conn->try_next_host)
{
pg_conn_host *ch;
struct addrinfo hint;
int thisport;
int ret;
char portstr[MAXPGPATH];
if (conn->whichhost + 1 >= conn->nconnhost)
{
/*
* Oops, no more hosts. An appropriate error message is already
* set up, so just set the right status.
*/
goto error_return;
}
conn->whichhost++;
/* Drop any address info for previous host */
release_conn_addrinfo(conn);
/*
* Look up info for the new host. On failure, log the problem in
* conn->errorMessage, then loop around to try the next host. (Note
* we don't clear try_next_host until we've succeeded.)
*/
ch = &conn->connhost[conn->whichhost];
/* Initialize hint structure */
MemSet(&hint, 0, sizeof(hint));
hint.ai_socktype = SOCK_STREAM;
conn->addrlist_family = hint.ai_family = AF_UNSPEC;
/* Figure out the port number we're going to use. */
if (ch->port == NULL || ch->port[0] == '\0')
thisport = DEF_PGPORT;
else
{
if (!parse_int_param(ch->port, &thisport, conn, "port"))
goto error_return;
if (thisport < 1 || thisport > 65535)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid port number: \"%s\"\n"),
ch->port);
goto keep_going;
}
}
snprintf(portstr, sizeof(portstr), "%d", thisport);
/* Use pg_getaddrinfo_all() to resolve the address */
switch (ch->type)
{
case CHT_HOST_NAME:
ret = pg_getaddrinfo_all(ch->host, portstr, &hint,
&conn->addrlist);
if (ret || !conn->addrlist)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not translate host name \"%s\" to address: %s\n"),
ch->host, gai_strerror(ret));
goto keep_going;
}
break;
case CHT_HOST_ADDRESS:
hint.ai_flags = AI_NUMERICHOST;
ret = pg_getaddrinfo_all(ch->hostaddr, portstr, &hint,
&conn->addrlist);
if (ret || !conn->addrlist)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not parse network address \"%s\": %s\n"),
ch->hostaddr, gai_strerror(ret));
goto keep_going;
}
break;
case CHT_UNIX_SOCKET:
#ifdef HAVE_UNIX_SOCKETS
conn->addrlist_family = hint.ai_family = AF_UNIX;
UNIXSOCK_PATH(portstr, thisport, ch->host);
if (strlen(portstr) >= UNIXSOCK_PATH_BUFLEN)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("Unix-domain socket path \"%s\" is too long (maximum %d bytes)\n"),
portstr,
(int) (UNIXSOCK_PATH_BUFLEN - 1));
goto keep_going;
}
/*
* NULL hostname tells pg_getaddrinfo_all to parse the service
* name as a Unix-domain socket path.
*/
ret = pg_getaddrinfo_all(NULL, portstr, &hint,
&conn->addrlist);
if (ret || !conn->addrlist)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not translate Unix-domain socket path \"%s\" to address: %s\n"),
portstr, gai_strerror(ret));
goto keep_going;
}
#else
Assert(false);
#endif
break;
}
/* OK, scan this addrlist for a working server address */
conn->addr_cur = conn->addrlist;
reset_connection_state_machine = true;
conn->try_next_host = false;
}
/* Reset connection state machine? */
if (reset_connection_state_machine)
{
/*
* (Re) initialize our connection control variables for a set of
* connection attempts to a single server address. These variables
* must persist across individual connection attempts, but we must
* reset them when we start to consider a new server.
*/
conn->pversion = PG_PROTOCOL(3, 0);
conn->send_appname = true;
#ifdef USE_SSL
/* initialize these values based on SSL mode */
conn->allow_ssl_try = (conn->sslmode[0] != 'd'); /* "disable" */
conn->wait_ssl_try = (conn->sslmode[0] == 'a'); /* "allow" */
#endif
reset_connection_state_machine = false;
need_new_connection = true;
}
/* Force a new connection (perhaps to the same server as before)? */
if (need_new_connection)
{
/* Drop any existing connection */
pqDropConnection(conn, true);
/* Reset all state obtained from old server */
pqDropServerData(conn);
/* Drop any PGresult we might have, too */
conn->asyncStatus = PGASYNC_IDLE;
conn->xactStatus = PQTRANS_IDLE;
pqClearAsyncResult(conn);
/* Reset conn->status to put the state machine in the right state */
conn->status = CONNECTION_NEEDED;
need_new_connection = false;
}
/* Now try to advance the state machine for this connection */
switch (conn->status)
{
case CONNECTION_NEEDED:
{
/*
* Try to initiate a connection to one of the addresses
* returned by pg_getaddrinfo_all(). conn->addr_cur is the
* next one to try.
*
* The extra level of braces here is historical. It's not
* worth reindenting this whole switch case to remove 'em.
*/
{
struct addrinfo *addr_cur = conn->addr_cur;
char host_addr[NI_MAXHOST];
/*
* Advance to next possible host, if we've tried all of
* the addresses for the current host.
*/
if (addr_cur == NULL)
{
conn->try_next_host = true;
goto keep_going;
}
/* Remember current address for possible error msg */
memcpy(&conn->raddr.addr, addr_cur->ai_addr,
addr_cur->ai_addrlen);
conn->raddr.salen = addr_cur->ai_addrlen;
/* set connip */
if (conn->connip != NULL)
{
free(conn->connip);
conn->connip = NULL;
}
getHostaddr(conn, host_addr, NI_MAXHOST);
if (strlen(host_addr) > 0)
conn->connip = strdup(host_addr);
/*
* purposely ignore strdup failure; not a big problem if
* it fails anyway.
*/
conn->sock = socket(addr_cur->ai_family, SOCK_STREAM, 0);
if (conn->sock == PGINVALID_SOCKET)
{
/*
* Silently ignore socket() failure if we have more
* addresses to try; this reduces useless chatter in
* cases where the address list includes both IPv4 and
* IPv6 but kernel only accepts one family.
*/
if (addr_cur->ai_next != NULL ||
conn->whichhost + 1 < conn->nconnhost)
{
conn->try_next_addr = true;
goto keep_going;
}
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not create socket: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
goto error_return;
}
/*
* Select socket options: no delay of outgoing data for
* TCP sockets, nonblock mode, close-on-exec. Try the
* next address if any of this fails.
*/
if (!IS_AF_UNIX(addr_cur->ai_family))
{
if (!connectNoDelay(conn))
{
/* error message already created */
conn->try_next_addr = true;
goto keep_going;
}
}
if (!pg_set_noblock(conn->sock))
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not set socket to nonblocking mode: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
conn->try_next_addr = true;
goto keep_going;
}
#ifdef F_SETFD
if (fcntl(conn->sock, F_SETFD, FD_CLOEXEC) == -1)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not set socket to close-on-exec mode: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
conn->try_next_addr = true;
goto keep_going;
}
#endif /* F_SETFD */
if (!IS_AF_UNIX(addr_cur->ai_family))
{
#ifndef WIN32
int on = 1;
#endif
int usekeepalives = useKeepalives(conn);
int err = 0;
if (usekeepalives < 0)
{
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("keepalives parameter must be an integer\n"));
err = 1;
}
else if (usekeepalives == 0)
{
/* Do nothing */
}
#ifndef WIN32
else if (setsockopt(conn->sock,
SOL_SOCKET, SO_KEEPALIVE,
(char *) &on, sizeof(on)) < 0)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("setsockopt(%s) failed: %s\n"),
"SO_KEEPALIVE",
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
err = 1;
}
else if (!setKeepalivesIdle(conn)
|| !setKeepalivesInterval(conn)
|| !setKeepalivesCount(conn))
err = 1;
#else /* WIN32 */
#ifdef SIO_KEEPALIVE_VALS
else if (!setKeepalivesWin32(conn))
err = 1;
#endif /* SIO_KEEPALIVE_VALS */
#endif /* WIN32 */
else if (!setTCPUserTimeout(conn))
err = 1;
if (err)
{
conn->try_next_addr = true;
goto keep_going;
}
}
/*----------
* We have three methods of blocking SIGPIPE during
* send() calls to this socket:
*
* - setsockopt(sock, SO_NOSIGPIPE)
* - send(sock, ..., MSG_NOSIGNAL)
* - setting the signal mask to SIG_IGN during send()
*
* The third method requires three syscalls per send,
* so we prefer either of the first two, but they are
* less portable. The state is tracked in the following
* members of PGconn:
*
* conn->sigpipe_so - we have set up SO_NOSIGPIPE
* conn->sigpipe_flag - we're specifying MSG_NOSIGNAL
*
* If we can use SO_NOSIGPIPE, then set sigpipe_so here
* and we're done. Otherwise, set sigpipe_flag so that
* we will try MSG_NOSIGNAL on sends. If we get an error
* with MSG_NOSIGNAL, we'll clear that flag and revert to
* signal masking.
*----------
*/
conn->sigpipe_so = false;
#ifdef MSG_NOSIGNAL
conn->sigpipe_flag = true;
#else
conn->sigpipe_flag = false;
#endif /* MSG_NOSIGNAL */
#ifdef SO_NOSIGPIPE
optval = 1;
if (setsockopt(conn->sock, SOL_SOCKET, SO_NOSIGPIPE,
(char *) &optval, sizeof(optval)) == 0)
{
conn->sigpipe_so = true;
conn->sigpipe_flag = false;
}
#endif /* SO_NOSIGPIPE */
/*
* Start/make connection. This should not block, since we
* are in nonblock mode. If it does, well, too bad.
*/
if (connect(conn->sock, addr_cur->ai_addr,
addr_cur->ai_addrlen) < 0)
{
if (SOCK_ERRNO == EINPROGRESS ||
#ifdef WIN32
SOCK_ERRNO == EWOULDBLOCK ||
#endif
SOCK_ERRNO == EINTR)
{
/*
* This is fine - we're in non-blocking mode, and
* the connection is in progress. Tell caller to
* wait for write-ready on socket.
*/
conn->status = CONNECTION_STARTED;
return PGRES_POLLING_WRITING;
}
/* otherwise, trouble */
}
else
{
/*
* Hm, we're connected already --- seems the "nonblock
* connection" wasn't. Advance the state machine and
* go do the next stuff.
*/
conn->status = CONNECTION_STARTED;
goto keep_going;
}
/*
* This connection failed. Add the error report to
* conn->errorMessage, then try the next address if any.
*/
connectFailureMessage(conn, SOCK_ERRNO);
conn->try_next_addr = true;
goto keep_going;
}
}
case CONNECTION_STARTED:
{
ACCEPT_TYPE_ARG3 optlen = sizeof(optval);
/*
* Write ready, since we've made it here, so the connection
* has been made ... or has failed.
*/
/*
* Now check (using getsockopt) that there is not an error
* state waiting for us on the socket.
*/
if (getsockopt(conn->sock, SOL_SOCKET, SO_ERROR,
(char *) &optval, &optlen) == -1)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not get socket error status: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
goto error_return;
}
else if (optval != 0)
{
/*
* When using a nonblocking connect, we will typically see
* connect failures at this point, so provide a friendly
* error message.
*/
connectFailureMessage(conn, optval);
/*
* Try the next address if any, just as in the case where
* connect() returned failure immediately.
*/
conn->try_next_addr = true;
goto keep_going;
}
/* Fill in the client address */
conn->laddr.salen = sizeof(conn->laddr.addr);
if (getsockname(conn->sock,
(struct sockaddr *) &conn->laddr.addr,
&conn->laddr.salen) < 0)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not get client address from socket: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
goto error_return;
}
/*
* Make sure we can write before advancing to next step.
*/
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
case CONNECTION_MADE:
{
char *startpacket;
int packetlen;
/*
* Implement requirepeer check, if requested and it's a
* Unix-domain socket.
*/
if (conn->requirepeer && conn->requirepeer[0] &&
IS_AF_UNIX(conn->raddr.addr.ss_family))
{
#ifndef WIN32
char pwdbuf[BUFSIZ];
struct passwd pass_buf;
struct passwd *pass;
int passerr;
#endif
uid_t uid;
gid_t gid;
errno = 0;
if (getpeereid(conn->sock, &uid, &gid) != 0)
{
/*
* Provide special error message if getpeereid is a
* stub
*/
if (errno == ENOSYS)
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("requirepeer parameter is not supported on this platform\n"));
else
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not get peer credentials: %s\n"),
strerror_r(errno, sebuf, sizeof(sebuf)));
goto error_return;
}
#ifndef WIN32
passerr = pqGetpwuid(uid, &pass_buf, pwdbuf, sizeof(pwdbuf), &pass);
if (pass == NULL)
{
if (passerr != 0)
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not look up local user ID %d: %s\n"),
(int) uid,
strerror_r(passerr, sebuf, sizeof(sebuf)));
else
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("local user with ID %d does not exist\n"),
(int) uid);
goto error_return;
}
if (strcmp(pass->pw_name, conn->requirepeer) != 0)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("requirepeer specifies \"%s\", but actual peer user name is \"%s\"\n"),
conn->requirepeer, pass->pw_name);
goto error_return;
}
#else /* WIN32 */
/* should have failed with ENOSYS above */
Assert(false);
#endif /* WIN32 */
}
if (IS_AF_UNIX(conn->raddr.addr.ss_family))
{
/* Don't request SSL or GSSAPI over Unix sockets */
#ifdef USE_SSL
conn->allow_ssl_try = false;
#endif
#ifdef ENABLE_GSS
conn->try_gss = false;
#endif
}
#ifdef ENABLE_GSS
/*
* If GSSAPI encryption is enabled, then call
* pg_GSS_have_cred_cache() which will return true if we can
* acquire credentials (and give us a handle to use in
* conn->gcred), and then send a packet to the server asking
* for GSSAPI Encryption (and skip past SSL negotiation and
* regular startup below).
*/
if (conn->try_gss && !conn->gctx)
conn->try_gss = pg_GSS_have_cred_cache(&conn->gcred);
if (conn->try_gss && !conn->gctx)
{
ProtocolVersion pv = pg_hton32(NEGOTIATE_GSS_CODE);
if (pqPacketSend(conn, 0, &pv, sizeof(pv)) != STATUS_OK)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not send GSSAPI negotiation packet: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
goto error_return;
}
/* Ok, wait for response */
conn->status = CONNECTION_GSS_STARTUP;
return PGRES_POLLING_READING;
}
else if (!conn->gctx && conn->gssencmode[0] == 'r')
{
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("GSSAPI encryption required but was impossible (possibly no credential cache, no server support, or using a local socket)\n"));
goto error_return;
}
#endif
#ifdef USE_SSL
/*
* If SSL is enabled and we haven't already got it running,
* request it instead of sending the startup message.
*/
if (conn->allow_ssl_try && !conn->wait_ssl_try &&
!conn->ssl_in_use)
{
ProtocolVersion pv;
/*
* Send the SSL request packet.
*
* Theoretically, this could block, but it really
* shouldn't since we only got here if the socket is
* write-ready.
*/
pv = pg_hton32(NEGOTIATE_SSL_CODE);
if (pqPacketSend(conn, 0, &pv, sizeof(pv)) != STATUS_OK)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not send SSL negotiation packet: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
goto error_return;
}
/* Ok, wait for response */
conn->status = CONNECTION_SSL_STARTUP;
return PGRES_POLLING_READING;
}
#endif /* USE_SSL */
/*
* Build the startup packet.
*/
if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
startpacket = pqBuildStartupPacket3(conn, &packetlen,
EnvironmentOptions);
else
startpacket = pqBuildStartupPacket2(conn, &packetlen,
EnvironmentOptions);
if (!startpacket)
{
/*
* will not appendbuffer here, since it's likely to also
* run out of memory
*/
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
goto error_return;
}
/*
* Send the startup packet.
*
* Theoretically, this could block, but it really shouldn't
* since we only got here if the socket is write-ready.
*/
if (pqPacketSend(conn, 0, startpacket, packetlen) != STATUS_OK)
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not send startup packet: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
free(startpacket);
goto error_return;
}
free(startpacket);
conn->status = CONNECTION_AWAITING_RESPONSE;
return PGRES_POLLING_READING;
}
/*
* Handle SSL negotiation: wait for postmaster messages and
* respond as necessary.
*/
case CONNECTION_SSL_STARTUP:
{
#ifdef USE_SSL
PostgresPollingStatusType pollres;
/*
* On first time through, get the postmaster's response to our
* SSL negotiation packet.
*/
if (!conn->ssl_in_use)
{
/*
* We use pqReadData here since it has the logic to
* distinguish no-data-yet from connection closure. Since
* conn->ssl isn't set, a plain recv() will occur.
*/
char SSLok;
int rdresult;
rdresult = pqReadData(conn);
if (rdresult < 0)
{
/* errorMessage is already filled in */
goto error_return;
}
if (rdresult == 0)
{
/* caller failed to wait for data */
return PGRES_POLLING_READING;
}
if (pqGetc(&SSLok, conn) < 0)
{
/* should not happen really */
return PGRES_POLLING_READING;
}
if (SSLok == 'S')
{
/* mark byte consumed */
conn->inStart = conn->inCursor;
/* Set up global SSL state if required */
if (pqsecure_initialize(conn) != 0)
goto error_return;
}
else if (SSLok == 'N')
{
/* mark byte consumed */
conn->inStart = conn->inCursor;
/* OK to do without SSL? */
if (conn->sslmode[0] == 'r' || /* "require" */
conn->sslmode[0] == 'v') /* "verify-ca" or
* "verify-full" */
{
/* Require SSL, but server does not want it */
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("server does not support SSL, but SSL was required\n"));
goto error_return;
}
/* Otherwise, proceed with normal startup */
conn->allow_ssl_try = false;
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
else if (SSLok == 'E')
{
/*
* Server failure of some sort, such as failure to
* fork a backend process. We need to process and
* report the error message, which might be formatted
* according to either protocol 2 or protocol 3.
* Rather than duplicate the code for that, we flip
* into AWAITING_RESPONSE state and let the code there
* deal with it. Note we have *not* consumed the "E"
* byte here.
*/
conn->status = CONNECTION_AWAITING_RESPONSE;
goto keep_going;
}
else
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("received invalid response to SSL negotiation: %c\n"),
SSLok);
goto error_return;
}
}
/*
* Begin or continue the SSL negotiation process.
*/
pollres = pqsecure_open_client(conn);
if (pollres == PGRES_POLLING_OK)
{
/* SSL handshake done, ready to send startup packet */
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
if (pollres == PGRES_POLLING_FAILED)
{
/*
* Failed ... if sslmode is "prefer" then do a non-SSL
* retry
*/
if (conn->sslmode[0] == 'p' /* "prefer" */
&& conn->allow_ssl_try /* redundant? */
&& !conn->wait_ssl_try) /* redundant? */
{
/* only retry once */
conn->allow_ssl_try = false;
need_new_connection = true;
goto keep_going;
}
/* Else it's a hard failure */
goto error_return;
}
/* Else, return POLLING_READING or POLLING_WRITING status */
return pollres;
#else /* !USE_SSL */
/* can't get here */
goto error_return;
#endif /* USE_SSL */
}
case CONNECTION_GSS_STARTUP:
{
#ifdef ENABLE_GSS
PostgresPollingStatusType pollres;
/*
* If we haven't yet, get the postmaster's response to our
* negotiation packet
*/
if (conn->try_gss && !conn->gctx)
{
char gss_ok;
int rdresult = pqReadData(conn);
if (rdresult < 0)
/* pqReadData fills in error message */
goto error_return;
else if (rdresult == 0)
/* caller failed to wait for data */
return PGRES_POLLING_READING;
if (pqGetc(&gss_ok, conn) < 0)
/* shouldn't happen... */
return PGRES_POLLING_READING;
if (gss_ok == 'E')
{
/*
* Server failure of some sort. Assume it's a
* protocol version support failure, and let's see if
* we can't recover (if it's not, we'll get a better
* error message on retry). Server gets fussy if we
* don't hang up the socket, though.
*/
conn->try_gss = false;
pqDropConnection(conn, true);
conn->status = CONNECTION_NEEDED;
goto keep_going;
}
/* mark byte consumed */
conn->inStart = conn->inCursor;
if (gss_ok == 'N')
{
/* Server doesn't want GSSAPI; fall back if we can */
if (conn->gssencmode[0] == 'r')
{
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("server doesn't support GSSAPI encryption, but it was required\n"));
goto error_return;
}
conn->try_gss = false;
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
else if (gss_ok != 'G')
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("received invalid response to GSSAPI negotiation: %c\n"),
gss_ok);
goto error_return;
}
}
/* Begin or continue GSSAPI negotiation */
pollres = pqsecure_open_gss(conn);
if (pollres == PGRES_POLLING_OK)
{
/* All set for startup packet */
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
else if (pollres == PGRES_POLLING_FAILED &&
conn->gssencmode[0] == 'p')
{
/*
* We failed, but we can retry on "prefer". Have to drop
* the current connection to do so, though.
*/
conn->try_gss = false;
pqDropConnection(conn, true);
conn->status = CONNECTION_NEEDED;
goto keep_going;
}
return pollres;
#else /* !ENABLE_GSS */
/* unreachable */
goto error_return;
#endif /* ENABLE_GSS */
}
/*
* Handle authentication exchange: wait for postmaster messages
* and respond as necessary.
*/
case CONNECTION_AWAITING_RESPONSE:
{
char beresp;
int msgLength;
int avail;
AuthRequest areq;
int res;
/*
* Scan the message from current point (note that if we find
* the message is incomplete, we will return without advancing
* inStart, and resume here next time).
*/
conn->inCursor = conn->inStart;
/* Read type byte */
if (pqGetc(&beresp, conn))
{
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
/*
* Validate message type: we expect only an authentication
* request or an error here. Anything else probably means
* it's not Postgres on the other end at all.
*/
if (!(beresp == 'R' || beresp == 'E'))
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext(
"expected authentication request from "
"server, but received %c\n"),
beresp);
goto error_return;
}
if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
{
/* Read message length word */
if (pqGetInt(&msgLength, 4, conn))
{
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
}
else
{
/* Set phony message length to disable checks below */
msgLength = 8;
}
/*
* Try to validate message length before using it.
* Authentication requests can't be very large, although GSS
* auth requests may not be that small. Errors can be a
* little larger, but not huge. If we see a large apparent
* length in an error, it means we're really talking to a
* pre-3.0-protocol server; cope.
*/
if (beresp == 'R' && (msgLength < 8 || msgLength > 2000))
{
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext(
"expected authentication request from "
"server, but received %c\n"),
beresp);
goto error_return;
}
if (beresp == 'E' && (msgLength < 8 || msgLength > 30000))
{
/* Handle error from a pre-3.0 server */
conn->inCursor = conn->inStart + 1; /* reread data */
if (pqGets_append(&conn->errorMessage, conn))
{
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
/* OK, we read the message; mark data consumed */
conn->inStart = conn->inCursor;
/*
* The postmaster typically won't end its message with a
* newline, so add one to conform to libpq conventions.
*/
appendPQExpBufferChar(&conn->errorMessage, '\n');
/*
* If we tried to open the connection in 3.0 protocol,
* fall back to 2.0 protocol.
*/
if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
{
conn->pversion = PG_PROTOCOL(2, 0);
need_new_connection = true;
goto keep_going;
}
goto error_return;
}
/*
* Can't process if message body isn't all here yet.
*
* (In protocol 2.0 case, we are assuming messages carry at
* least 4 bytes of data.)
*/
msgLength -= 4;
avail = conn->inEnd - conn->inCursor;
if (avail < msgLength)
{
/*
* Before returning, try to enlarge the input buffer if
* needed to hold the whole message; see notes in
* pqParseInput3.
*/
if (pqCheckInBufferSpace(conn->inCursor + (size_t) msgLength,
conn))
goto error_return;
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
/* Handle errors. */
if (beresp == 'E')
{
if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
{
if (pqGetErrorNotice3(conn, true))
{
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
}
else
{
if (pqGets_append(&conn->errorMessage, conn))
{
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
}
/* OK, we read the message; mark data consumed */
conn->inStart = conn->inCursor;
/* Check to see if we should mention pgpassfile */
pgpassfileWarning(conn);
#ifdef ENABLE_GSS
/*
* If gssencmode is "prefer" and we're using GSSAPI, retry
* without it.
*/
if (conn->gssenc && conn->gssencmode[0] == 'p')
{
OM_uint32 minor;
/* postmaster expects us to drop the connection */
conn->try_gss = false;
conn->gssenc = false;
gss_delete_sec_context(&minor, &conn->gctx, NULL);
pqDropConnection(conn, true);
conn->status = CONNECTION_NEEDED;
goto keep_going;
}
#endif
#ifdef USE_SSL
/*
* if sslmode is "allow" and we haven't tried an SSL
* connection already, then retry with an SSL connection
*/
if (conn->sslmode[0] == 'a' /* "allow" */
&& !conn->ssl_in_use
&& conn->allow_ssl_try
&& conn->wait_ssl_try)
{
/* only retry once */
conn->wait_ssl_try = false;
need_new_connection = true;
goto keep_going;
}
/*
* if sslmode is "prefer" and we're in an SSL connection,
* then do a non-SSL retry
*/
if (conn->sslmode[0] == 'p' /* "prefer" */
&& conn->ssl_in_use
&& conn->allow_ssl_try /* redundant? */
&& !conn->wait_ssl_try) /* redundant? */
{
/* only retry once */
conn->allow_ssl_try = false;
need_new_connection = true;
goto keep_going;
}
#endif
goto error_return;
}
/* It is an authentication request. */
conn->auth_req_received = true;
/* Get the type of request. */
if (pqGetInt((int *) &areq, 4, conn))
{
/* We'll come back when there are more data */
return PGRES_POLLING_READING;
}
msgLength -= 4;
/*
* Ensure the password salt is in the input buffer, if it's an
* MD5 request. All the other authentication methods that
* contain extra data in the authentication request are only
* supported in protocol version 3, in which case we already
* read the whole message above.
*/
if (areq == AUTH_REQ_MD5 && PG_PROTOCOL_MAJOR(conn->pversion) < 3)
{
msgLength += 4;
avail = conn->inEnd - conn->inCursor;
if (avail < 4)
{
/*
* Before returning, try to enlarge the input buffer
* if needed to hold the whole message; see notes in
* pqParseInput3.
*/
if (pqCheckInBufferSpace(conn->inCursor + (size_t) 4,
conn))
goto error_return;
/* We'll come back when there is more data */
return PGRES_POLLING_READING;
}
}
/*
* Process the rest of the authentication request message, and
* respond to it if necessary.
*
* Note that conn->pghost must be non-NULL if we are going to
* avoid the Kerberos code doing a hostname look-up.
*/
res = pg_fe_sendauth(areq, msgLength, conn);
conn->errorMessage.len = strlen(conn->errorMessage.data);
/* OK, we have processed the message; mark data consumed */
conn->inStart = conn->inCursor;
if (res != STATUS_OK)
goto error_return;
/*
* Just make sure that any data sent by pg_fe_sendauth is
* flushed out. Although this theoretically could block, it
* really shouldn't since we don't send large auth responses.
*/
if (pqFlush(conn))
goto error_return;
if (areq == AUTH_REQ_OK)
{
/* We are done with authentication exchange */
conn->status = CONNECTION_AUTH_OK;
/*
* Set asyncStatus so that PQgetResult will think that
* what comes back next is the result of a query. See
* below.
*/
conn->asyncStatus = PGASYNC_BUSY;
}
/* Look to see if we have more data yet. */
goto keep_going;
}
case CONNECTION_AUTH_OK:
{
/*
* Now we expect to hear from the backend. A ReadyForQuery
* message indicates that startup is successful, but we might
* also get an Error message indicating failure. (Notice
* messages indicating nonfatal warnings are also allowed by
* the protocol, as are ParameterStatus and BackendKeyData
* messages.) Easiest way to handle this is to let
* PQgetResult() read the messages. We just have to fake it
* out about the state of the connection, by setting
* asyncStatus = PGASYNC_BUSY (done above).
*/
if (PQisBusy(conn))
return PGRES_POLLING_READING;
res = PQgetResult(conn);
/*
* NULL return indicating we have gone to IDLE state is
* expected
*/
if (res)
{
if (res->resultStatus != PGRES_FATAL_ERROR)
appendPQExpBufferStr(&conn->errorMessage,
libpq_gettext("unexpected message from server during startup\n"));
else if (conn->send_appname &&
(conn->appname || conn->fbappname))
{
/*
* If we tried to send application_name, check to see
* if the error is about that --- pre-9.0 servers will
* reject it at this stage of the process. If so,
* close the connection and retry without sending
* application_name. We could possibly get a false
* SQLSTATE match here and retry uselessly, but there
* seems no great harm in that; we'll just get the
* same error again if it's unrelated.
*/
const char *sqlstate;
sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
if (sqlstate &&
strcmp(sqlstate, ERRCODE_APPNAME_UNKNOWN) == 0)
{
PQclear(res);
conn->send_appname = false;
need_new_connection = true;
goto keep_going;
}
}
/*
* if the resultStatus is FATAL, then conn->errorMessage
* already has a copy of the error; needn't copy it back.
* But add a newline if it's not there already, since
* postmaster error messages may not have one.
*/
if (conn->errorMessage.len <= 0 ||
conn->errorMessage.data[conn->errorMessage.len - 1] != '\n')
appendPQExpBufferChar(&conn->errorMessage, '\n');
PQclear(res);
goto error_return;
}
/* Fire up post-connection housekeeping if needed */
if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
{
conn->status = CONNECTION_SETENV;
conn->setenv_state = SETENV_STATE_CLIENT_ENCODING_SEND;
conn->next_eo = EnvironmentOptions;
return PGRES_POLLING_WRITING;
}
/* Almost there now ... */
conn->status = CONNECTION_CHECK_TARGET;
goto keep_going;
}
case CONNECTION_CHECK_TARGET:
{
/*
* If a read-write connection is required, see if we have one.
*
* Servers before 7.4 lack the transaction_read_only GUC, but
* by the same token they don't have any read-only mode, so we
* may just skip the test in that case.
*/
if (conn->sversion >= 70400 &&
conn->target_session_attrs != NULL &&
strcmp(conn->target_session_attrs, "read-write") == 0)
{
/*
* Save existing error messages across the PQsendQuery
* attempt. This is necessary because PQsendQuery is
* going to reset conn->errorMessage, so we would lose
* error messages related to previous hosts we have tried
* and failed to connect to.
*/
if (!saveErrorMessage(conn, &savedMessage))
goto error_return;
conn->status = CONNECTION_OK;
if (!PQsendQuery(conn,
"SHOW transaction_read_only"))
{
restoreErrorMessage(conn, &savedMessage);
goto error_return;
}
conn->status = CONNECTION_CHECK_WRITABLE;
restoreErrorMessage(conn, &savedMessage);
return PGRES_POLLING_READING;
}
/* We can release the address list now. */
release_conn_addrinfo(conn);
/* We are open for business! */
conn->status = CONNECTION_OK;
return PGRES_POLLING_OK;
}
case CONNECTION_SETENV:
{
/*
* Do post-connection housekeeping (only needed in protocol
* 2.0).
*
* We pretend that the connection is OK for the duration of
* these queries.
*/
conn->status = CONNECTION_OK;
switch (pqSetenvPoll(conn))
{
case PGRES_POLLING_OK: /* Success */
break;
case PGRES_POLLING_READING: /* Still going */
conn->status = CONNECTION_SETENV;
return PGRES_POLLING_READING;
case PGRES_POLLING_WRITING: /* Still going */
conn->status = CONNECTION_SETENV;
return PGRES_POLLING_WRITING;
default:
goto error_return;
}
/* Almost there now ... */
conn->status = CONNECTION_CHECK_TARGET;
goto keep_going;
}
case CONNECTION_CONSUME:
{
conn->status = CONNECTION_OK;
if (!PQconsumeInput(conn))
goto error_return;
if (PQisBusy(conn))
{
conn->status = CONNECTION_CONSUME;
return PGRES_POLLING_READING;
}
/*
* Call PQgetResult() again to consume NULL result.
*/
res = PQgetResult(conn);
if (res != NULL)
{
PQclear(res);
conn->status = CONNECTION_CONSUME;
goto keep_going;
}
/* We can release the address list now. */
release_conn_addrinfo(conn);
/* We are open for business! */
conn->status = CONNECTION_OK;
return PGRES_POLLING_OK;
}
case CONNECTION_CHECK_WRITABLE:
{
const char *displayed_host;
const char *displayed_port;
if (!saveErrorMessage(conn, &savedMessage))
goto error_return;
conn->status = CONNECTION_OK;
if (!PQconsumeInput(conn))
{
restoreErrorMessage(conn, &savedMessage);
goto error_return;
}
if (PQisBusy(conn))
{
conn->status = CONNECTION_CHECK_WRITABLE;
restoreErrorMessage(conn, &savedMessage);
return PGRES_POLLING_READING;
}
res = PQgetResult(conn);
if (res && (PQresultStatus(res) == PGRES_TUPLES_OK) &&
PQntuples(res) == 1)
{
char *val;
val = PQgetvalue(res, 0, 0);
if (strncmp(val, "on", 2) == 0)
{
/* Not writable; fail this connection. */
PQclear(res);
restoreErrorMessage(conn, &savedMessage);
/* Append error report to conn->errorMessage. */
if (conn->connhost[conn->whichhost].type == CHT_HOST_ADDRESS)
displayed_host = conn->connhost[conn->whichhost].hostaddr;
else
displayed_host = conn->connhost[conn->whichhost].host;
displayed_port = conn->connhost[conn->whichhost].port;
if (displayed_port == NULL || displayed_port[0] == '\0')
displayed_port = DEF_PGPORT_STR;
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not make a writable "
"connection to server "
"\"%s:%s\"\n"),
displayed_host, displayed_port);
/* Close connection politely. */
conn->status = CONNECTION_OK;
sendTerminateConn(conn);
/*
* Try next host if any, but we don't want to consider
* additional addresses for this host.
*/
conn->try_next_host = true;
goto keep_going;
}
/* Session is read-write, so we're good. */
PQclear(res);
termPQExpBuffer(&savedMessage);
/*
* Finish reading any remaining messages before being
* considered as ready.
*/
conn->status = CONNECTION_CONSUME;
goto keep_going;
}
/*
* Something went wrong with "SHOW transaction_read_only". We
* should try next addresses.
*/
if (res)
PQclear(res);
restoreErrorMessage(conn, &savedMessage);
/* Append error report to conn->errorMessage. */
if (conn->connhost[conn->whichhost].type == CHT_HOST_ADDRESS)
displayed_host = conn->connhost[conn->whichhost].hostaddr;
else
displayed_host = conn->connhost[conn->whichhost].host;
displayed_port = conn->connhost[conn->whichhost].port;
if (displayed_port == NULL || displayed_port[0] == '\0')
displayed_port = DEF_PGPORT_STR;
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("test \"SHOW transaction_read_only\" failed "
"on server \"%s:%s\"\n"),
displayed_host, displayed_port);
/* Close connection politely. */
conn->status = CONNECTION_OK;
sendTerminateConn(conn);
/* Try next address */
conn->try_next_addr = true;
goto keep_going;
}
default:
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("invalid connection state %d, "
"probably indicative of memory corruption\n"),
conn->status);
goto error_return;
}
/* Unreachable */
error_return:
/*
* We used to close the socket at this point, but that makes it awkward
* for those above us if they wish to remove this socket from their own
* records (an fd_set for example). We'll just have this socket closed
* when PQfinish is called (which is compulsory even after an error, since
* the connection structure must be freed).
*/
conn->status = CONNECTION_BAD;
return PGRES_POLLING_FAILED;
}
/*
* internal_ping
* Determine if a server is running and if we can connect to it.
*
* The argument is a connection that's been started, but not completed.
*/
static PGPing
internal_ping(PGconn *conn)
{
/* Say "no attempt" if we never got to PQconnectPoll */
if (!conn || !conn->options_valid)
return PQPING_NO_ATTEMPT;
/* Attempt to complete the connection */
if (conn->status != CONNECTION_BAD)
(void) connectDBComplete(conn);
/* Definitely OK if we succeeded */
if (conn->status != CONNECTION_BAD)
return PQPING_OK;
/*
* Here begins the interesting part of "ping": determine the cause of the
* failure in sufficient detail to decide what to return. We do not want
* to report that the server is not up just because we didn't have a valid
* password, for example. In fact, any sort of authentication request
* implies the server is up. (We need this check since the libpq side of
* things might have pulled the plug on the connection before getting an
* error as such from the postmaster.)
*/
if (conn->auth_req_received)
return PQPING_OK;
/*
* If we failed to get any ERROR response from the postmaster, report
* PQPING_NO_RESPONSE. This result could be somewhat misleading for a
* pre-7.4 server, since it won't send back a SQLSTATE, but those are long
* out of support. Another corner case where the server could return a
* failure without a SQLSTATE is fork failure, but PQPING_NO_RESPONSE
* isn't totally unreasonable for that anyway. We expect that every other
* failure case in a modern server will produce a report with a SQLSTATE.
*
* NOTE: whenever we get around to making libpq generate SQLSTATEs for
* client-side errors, we should either not store those into
* last_sqlstate, or add an extra flag so we can tell client-side errors
* apart from server-side ones.
*/
if (strlen(conn->last_sqlstate) != 5)
return PQPING_NO_RESPONSE;
/*
* Report PQPING_REJECT if server says it's not accepting connections. (We
* distinguish this case mainly for the convenience of pg_ctl.)
*/
if (strcmp(conn->last_sqlstate, ERRCODE_CANNOT_CONNECT_NOW) == 0)
return PQPING_REJECT;
/*
* Any other SQLSTATE can be taken to indicate that the server is up.
* Presumably it didn't like our username, password, or database name; or
* perhaps it had some transient failure, but that should not be taken as
* meaning "it's down".
*/
return PQPING_OK;
}
/*
* makeEmptyPGconn
* - create a PGconn data structure with (as yet) no interesting data
*/
static PGconn *
makeEmptyPGconn(void)
{
PGconn *conn;
#ifdef WIN32
/*
* Make sure socket support is up and running.
*/
WSADATA wsaData;
if (WSAStartup(MAKEWORD(1, 1), &wsaData))
return NULL;
WSASetLastError(0);
#endif
conn = (PGconn *) malloc(sizeof(PGconn));
if (conn == NULL)
{
#ifdef WIN32
WSACleanup();
#endif
return conn;
}
/* Zero all pointers and booleans */
MemSet(conn, 0, sizeof(PGconn));
/* install default notice hooks */
conn->noticeHooks.noticeRec = defaultNoticeReceiver;
conn->noticeHooks.noticeProc = defaultNoticeProcessor;
conn->status = CONNECTION_BAD;
conn->asyncStatus = PGASYNC_IDLE;
conn->xactStatus = PQTRANS_IDLE;
conn->options_valid = false;
conn->nonblocking = false;
conn->setenv_state = SETENV_STATE_IDLE;
conn->client_encoding = PG_SQL_ASCII;
conn->std_strings = false; /* unless server says differently */
conn->verbosity = PQERRORS_DEFAULT;
conn->show_context = PQSHOW_CONTEXT_ERRORS;
conn->sock = PGINVALID_SOCKET;
#ifdef ENABLE_GSS
conn->try_gss = true;
#endif
/*
* We try to send at least 8K at a time, which is the usual size of pipe
* buffers on Unix systems. That way, when we are sending a large amount
* of data, we avoid incurring extra kernel context swaps for partial
* bufferloads. The output buffer is initially made 16K in size, and we
* try to dump it after accumulating 8K.
*
* With the same goal of minimizing context swaps, the input buffer will
* be enlarged anytime it has less than 8K free, so we initially allocate
* twice that.
*/
conn->inBufSize = 16 * 1024;
conn->inBuffer = (char *) malloc(conn->inBufSize);
conn->outBufSize = 16 * 1024;
conn->outBuffer = (char *) malloc(conn->outBufSize);
conn->rowBufLen = 32;
conn->rowBuf = (PGdataValue *) malloc(conn->rowBufLen * sizeof(PGdataValue));
initPQExpBuffer(&conn->errorMessage);
initPQExpBuffer(&conn->workBuffer);
if (conn->inBuffer == NULL ||
conn->outBuffer == NULL ||
conn->rowBuf == NULL ||
PQExpBufferBroken(&conn->errorMessage) ||
PQExpBufferBroken(&conn->workBuffer))
{
/* out of memory already :-( */
freePGconn(conn);
conn = NULL;
}
return conn;
}
/*
* freePGconn
* - free an idle (closed) PGconn data structure
*
* NOTE: this should not overlap any functionality with closePGconn().
* Clearing/resetting of transient state belongs there; what we do here is
* release data that is to be held for the life of the PGconn structure.
* If a value ought to be cleared/freed during PQreset(), do it there not here.
*/
static void
freePGconn(PGconn *conn)
{
int i;
/* let any event procs clean up their state data */
for (i = 0; i < conn->nEvents; i++)
{
PGEventConnDestroy evt;
evt.conn = conn;
(void) conn->events[i].proc(PGEVT_CONNDESTROY, &evt,
conn->events[i].passThrough);
free(conn->events[i].name);
}
/* clean up pg_conn_host structures */
if (conn->connhost != NULL)
{
for (i = 0; i < conn->nconnhost; ++i)
{
if (conn->connhost[i].host != NULL)
free(conn->connhost[i].host);
if (conn->connhost[i].hostaddr != NULL)
free(conn->connhost[i].hostaddr);
if (conn->connhost[i].port != NULL)
free(conn->connhost[i].port);
if (conn->connhost[i].password != NULL)
{
explicit_bzero(conn->connhost[i].password, strlen(conn->connhost[i].password));
free(conn->connhost[i].password);
}
}
free(conn->connhost);
}
if (conn->client_encoding_initial)
free(conn->client_encoding_initial);
if (conn->events)
free(conn->events);
if (conn->pghost)
free(conn->pghost);
if (conn->pghostaddr)
free(conn->pghostaddr);
if (conn->pgport)
free(conn->pgport);
if (conn->pgtty)
free(conn->pgtty);
if (conn->connect_timeout)
free(conn->connect_timeout);
if (conn->pgtcp_user_timeout)
free(conn->pgtcp_user_timeout);
if (conn->pgoptions)
free(conn->pgoptions);
if (conn->appname)
free(conn->appname);
if (conn->fbappname)
free(conn->fbappname);
if (conn->dbName)
free(conn->dbName);
if (conn->replication)
free(conn->replication);
if (conn->pguser)
free(conn->pguser);
if (conn->pgpass)
{
explicit_bzero(conn->pgpass, strlen(conn->pgpass));
free(conn->pgpass);
}
if (conn->pgpassfile)
free(conn->pgpassfile);
if (conn->channel_binding)
free(conn->channel_binding);
if (conn->keepalives)
free(conn->keepalives);
if (conn->keepalives_idle)
free(conn->keepalives_idle);
if (conn->keepalives_interval)
free(conn->keepalives_interval);
if (conn->keepalives_count)
free(conn->keepalives_count);
if (conn->sslmode)
free(conn->sslmode);
if (conn->sslcert)
free(conn->sslcert);
if (conn->sslkey)
free(conn->sslkey);
if (conn->sslpassword)
free(conn->sslpassword);
if (conn->sslrootcert)
free(conn->sslrootcert);
if (conn->sslcrl)
free(conn->sslcrl);
if (conn->sslcompression)
free(conn->sslcompression);
if (conn->requirepeer)
free(conn->requirepeer);
if (conn->sslminprotocolversion)
free(conn->sslminprotocolversion);
if (conn->sslmaxprotocolversion)
free(conn->sslmaxprotocolversion);
if (conn->gssencmode)
free(conn->gssencmode);
if (conn->krbsrvname)
free(conn->krbsrvname);
if (conn->gsslib)
free(conn->gsslib);
if (conn->connip)
free(conn->connip);
#ifdef ENABLE_GSS
if (conn->gcred != GSS_C_NO_CREDENTIAL)
{
OM_uint32 minor;
gss_release_cred(&minor, &conn->gcred);
conn->gcred = GSS_C_NO_CREDENTIAL;
}
if (conn->gctx)
{
OM_uint32 minor;
gss_delete_sec_context(&minor, &conn->gctx, GSS_C_NO_BUFFER);
conn->gctx = NULL;
}
#endif
/* Note that conn->Pfdebug is not ours to close or free */
if (conn->last_query)
free(conn->last_query);
if (conn->write_err_msg)
free(conn->write_err_msg);
if (conn->inBuffer)
free(conn->inBuffer);
if (conn->outBuffer)
free(conn->outBuffer);
if (conn->rowBuf)
free(conn->rowBuf);
if (conn->target_session_attrs)
free(conn->target_session_attrs);
termPQExpBuffer(&conn->errorMessage);
termPQExpBuffer(&conn->workBuffer);
free(conn);
#ifdef WIN32
WSACleanup();
#endif
}
/*
* release_conn_addrinfo
* - Free any addrinfo list in the PGconn.
*/
static void
release_conn_addrinfo(PGconn *conn)
{
if (conn->addrlist)
{
pg_freeaddrinfo_all(conn->addrlist_family, conn->addrlist);
conn->addrlist = NULL;
conn->addr_cur = NULL; /* for safety */
}
}
/*
* sendTerminateConn
* - Send a terminate message to backend.
*/
static void
sendTerminateConn(PGconn *conn)
{
/*
* Note that the protocol doesn't allow us to send Terminate messages
* during the startup phase.
*/
if (conn->sock != PGINVALID_SOCKET && conn->status == CONNECTION_OK)
{
/*
* Try to send "close connection" message to backend. Ignore any
* error.
*/
pqPutMsgStart('X', false, conn);
pqPutMsgEnd(conn);
(void) pqFlush(conn);
}
}
/*
* closePGconn
* - properly close a connection to the backend
*
* This should reset or release all transient state, but NOT the connection
* parameters. On exit, the PGconn should be in condition to start a fresh
* connection with the same parameters (see PQreset()).
*/
static void
closePGconn(PGconn *conn)
{
/*
* If possible, send Terminate message to close the connection politely.
*/
sendTerminateConn(conn);
/*
* Must reset the blocking status so a possible reconnect will work.
*
* Don't call PQsetnonblocking() because it will fail if it's unable to
* flush the connection.
*/
conn->nonblocking = false;
/*
* Close the connection, reset all transient state, flush I/O buffers.
*/
pqDropConnection(conn, true);
conn->status = CONNECTION_BAD; /* Well, not really _bad_ - just absent */
conn->asyncStatus = PGASYNC_IDLE;
conn->xactStatus = PQTRANS_IDLE;
pqClearAsyncResult(conn); /* deallocate result */
resetPQExpBuffer(&conn->errorMessage);
release_conn_addrinfo(conn);
/* Reset all state obtained from server, too */
pqDropServerData(conn);
}
/*
* PQfinish: properly close a connection to the backend. Also frees
* the PGconn data structure so it shouldn't be re-used after this.
*/
void
PQfinish(PGconn *conn)
{
if (conn)
{
closePGconn(conn);
freePGconn(conn);
}
}
/*
* PQreset: resets the connection to the backend by closing the
* existing connection and creating a new one.
*/
void
PQreset(PGconn *conn)
{
if (conn)
{
closePGconn(conn);
if (connectDBStart(conn) && connectDBComplete(conn))
{
/*
* Notify event procs of successful reset. We treat an event proc
* failure as disabling the connection ... good idea?
*/
int i;
for (i = 0; i < conn->nEvents; i++)
{
PGEventConnReset evt;
evt.conn = conn;
if (!conn->events[i].proc(PGEVT_CONNRESET, &evt,
conn->events[i].passThrough))
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("PGEventProc \"%s\" failed during PGEVT_CONNRESET event\n"),
conn->events[i].name);
break;
}
}
}
}
}
/*
* PQresetStart:
* resets the connection to the backend
* closes the existing connection and makes a new one
* Returns 1 on success, 0 on failure.
*/
int
PQresetStart(PGconn *conn)
{
if (conn)
{
closePGconn(conn);
return connectDBStart(conn);
}
return 0;
}
/*
* PQresetPoll:
* resets the connection to the backend
* closes the existing connection and makes a new one
*/
PostgresPollingStatusType
PQresetPoll(PGconn *conn)
{
if (conn)
{
PostgresPollingStatusType status = PQconnectPoll(conn);
if (status == PGRES_POLLING_OK)
{
/*
* Notify event procs of successful reset. We treat an event proc
* failure as disabling the connection ... good idea?
*/
int i;
for (i = 0; i < conn->nEvents; i++)
{
PGEventConnReset evt;
evt.conn = conn;
if (!conn->events[i].proc(PGEVT_CONNRESET, &evt,
conn->events[i].passThrough))
{
conn->status = CONNECTION_BAD;
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("PGEventProc \"%s\" failed during PGEVT_CONNRESET event\n"),
conn->events[i].name);
return PGRES_POLLING_FAILED;
}
}
}
return status;
}
return PGRES_POLLING_FAILED;
}
/*
* PQgetCancel: get a PGcancel structure corresponding to a connection.
*
* A copy is needed to be able to cancel a running query from a different
* thread. If the same structure is used all structure members would have
* to be individually locked (if the entire structure was locked, it would
* be impossible to cancel a synchronous query because the structure would
* have to stay locked for the duration of the query).
*/
PGcancel *
PQgetCancel(PGconn *conn)
{
PGcancel *cancel;
if (!conn)
return NULL;
if (conn->sock == PGINVALID_SOCKET)
return NULL;
cancel = malloc(sizeof(PGcancel));
if (cancel == NULL)
return NULL;
memcpy(&cancel->raddr, &conn->raddr, sizeof(SockAddr));
cancel->be_pid = conn->be_pid;
cancel->be_key = conn->be_key;
return cancel;
}
/* PQfreeCancel: free a cancel structure */
void
PQfreeCancel(PGcancel *cancel)
{
if (cancel)
free(cancel);
}
/*
* PQcancel and PQrequestCancel: attempt to request cancellation of the
* current operation.
*
* The return value is true if the cancel request was successfully
* dispatched, false if not (in which case an error message is available).
* Note: successful dispatch is no guarantee that there will be any effect at
* the backend. The application must read the operation result as usual.
*
* CAUTION: we want this routine to be safely callable from a signal handler
* (for example, an application might want to call it in a SIGINT handler).
* This means we cannot use any C library routine that might be non-reentrant.
* malloc/free are often non-reentrant, and anything that might call them is
* just as dangerous. We avoid sprintf here for that reason. Building up
* error messages with strcpy/strcat is tedious but should be quite safe.
* We also save/restore errno in case the signal handler support doesn't.
*
* internal_cancel() is an internal helper function to make code-sharing
* between the two versions of the cancel function possible.
*/
static int
internal_cancel(SockAddr *raddr, int be_pid, int be_key,
char *errbuf, int errbufsize)
{
int save_errno = SOCK_ERRNO;
pgsocket tmpsock = PGINVALID_SOCKET;
char sebuf[PG_STRERROR_R_BUFLEN];
int maxlen;
struct
{
uint32 packetlen;
CancelRequestPacket cp;
} crp;
/*
* We need to open a temporary connection to the postmaster. Do this with
* only kernel calls.
*/
if ((tmpsock = socket(raddr->addr.ss_family, SOCK_STREAM, 0)) == PGINVALID_SOCKET)
{
strlcpy(errbuf, "PQcancel() -- socket() failed: ", errbufsize);
goto cancel_errReturn;
}
retry3:
if (connect(tmpsock, (struct sockaddr *) &raddr->addr,
raddr->salen) < 0)
{
if (SOCK_ERRNO == EINTR)
/* Interrupted system call - we'll just try again */
goto retry3;
strlcpy(errbuf, "PQcancel() -- connect() failed: ", errbufsize);
goto cancel_errReturn;
}
/*
* We needn't set nonblocking I/O or NODELAY options here.
*/
/* Create and send the cancel request packet. */
crp.packetlen = pg_hton32((uint32) sizeof(crp));
crp.cp.cancelRequestCode = (MsgType) pg_hton32(CANCEL_REQUEST_CODE);
crp.cp.backendPID = pg_hton32(be_pid);
crp.cp.cancelAuthCode = pg_hton32(be_key);
retry4:
if (send(tmpsock, (char *) &crp, sizeof(crp), 0) != (int) sizeof(crp))
{
if (SOCK_ERRNO == EINTR)
/* Interrupted system call - we'll just try again */
goto retry4;
strlcpy(errbuf, "PQcancel() -- send() failed: ", errbufsize);
goto cancel_errReturn;
}
/*
* Wait for the postmaster to close the connection, which indicates that
* it's processed the request. Without this delay, we might issue another
* command only to find that our cancel zaps that command instead of the
* one we thought we were canceling. Note we don't actually expect this
* read to obtain any data, we are just waiting for EOF to be signaled.
*/
retry5:
if (recv(tmpsock, (char *) &crp, 1, 0) < 0)
{
if (SOCK_ERRNO == EINTR)
/* Interrupted system call - we'll just try again */
goto retry5;
/* we ignore other error conditions */
}
/* All done */
closesocket(tmpsock);
SOCK_ERRNO_SET(save_errno);
return true;
cancel_errReturn:
/*
* Make sure we don't overflow the error buffer. Leave space for the \n at
* the end, and for the terminating zero.
*/
maxlen = errbufsize - strlen(errbuf) - 2;
if (maxlen >= 0)
{
strncat(errbuf, SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)),
maxlen);
strcat(errbuf, "\n");
}
if (tmpsock != PGINVALID_SOCKET)
closesocket(tmpsock);
SOCK_ERRNO_SET(save_errno);
return false;
}
/*
* PQcancel: request query cancel
*
* Returns true if able to send the cancel request, false if not.
*
* On failure, an error message is stored in *errbuf, which must be of size
* errbufsize (recommended size is 256 bytes). *errbuf is not changed on
* success return.
*/
int
PQcancel(PGcancel *cancel, char *errbuf, int errbufsize)
{
if (!cancel)
{
strlcpy(errbuf, "PQcancel() -- no cancel object supplied", errbufsize);
return false;
}
return internal_cancel(&cancel->raddr, cancel->be_pid, cancel->be_key,
errbuf, errbufsize);
}
/*
* PQrequestCancel: old, not thread-safe function for requesting query cancel
*
* Returns true if able to send the cancel request, false if not.
*
* On failure, the error message is saved in conn->errorMessage; this means
* that this can't be used when there might be other active operations on
* the connection object.
*
* NOTE: error messages will be cut off at the current size of the
* error message buffer, since we dare not try to expand conn->errorMessage!
*/
int
PQrequestCancel(PGconn *conn)
{
int r;
/* Check we have an open connection */
if (!conn)
return false;
if (conn->sock == PGINVALID_SOCKET)
{
strlcpy(conn->errorMessage.data,
"PQrequestCancel() -- connection is not open\n",
conn->errorMessage.maxlen);
conn->errorMessage.len = strlen(conn->errorMessage.data);
return false;
}
r = internal_cancel(&conn->raddr, conn->be_pid, conn->be_key,
conn->errorMessage.data, conn->errorMessage.maxlen);
if (!r)
conn->errorMessage.len = strlen(conn->errorMessage.data);
return r;
}
/*
* pqPacketSend() -- convenience routine to send a message to server.
*
* pack_type: the single-byte message type code. (Pass zero for startup
* packets, which have no message type code.)
*
* buf, buf_len: contents of message. The given length includes only what
* is in buf; the message type and message length fields are added here.
*
* RETURNS: STATUS_ERROR if the write fails, STATUS_OK otherwise.
* SIDE_EFFECTS: may block.
*
* Note: all messages sent with this routine have a length word, whether
* it's protocol 2.0 or 3.0.
*/
int
pqPacketSend(PGconn *conn, char pack_type,
const void *buf, size_t buf_len)
{
/* Start the message. */
if (pqPutMsgStart(pack_type, true, conn))
return STATUS_ERROR;
/* Send the message body. */
if (pqPutnchar(buf, buf_len, conn))
return STATUS_ERROR;
/* Finish the message. */
if (pqPutMsgEnd(conn))
return STATUS_ERROR;
/* Flush to ensure backend gets it. */
if (pqFlush(conn))
return STATUS_ERROR;
return STATUS_OK;
}
#ifdef USE_LDAP
#define LDAP_URL "ldap://"
#define LDAP_DEF_PORT 389
#define PGLDAP_TIMEOUT 2
#define ld_is_sp_tab(x) ((x) == ' ' || (x) == '\t')
#define ld_is_nl_cr(x) ((x) == '\r' || (x) == '\n')
/*
* ldapServiceLookup
*
* Search the LDAP URL passed as first argument, treat the result as a
* string of connection options that are parsed and added to the array of
* options passed as second argument.
*
* LDAP URLs must conform to RFC 1959 without escape sequences.
* ldap://host:port/dn?attributes?scope?filter?extensions
*
* Returns
* 0 if the lookup was successful,
* 1 if the connection to the LDAP server could be established but
* the search was unsuccessful,
* 2 if a connection could not be established, and
* 3 if a fatal error occurred.
*
* An error message is returned in the third argument for return codes 1 and 3.
*/
static int
ldapServiceLookup(const char *purl, PQconninfoOption *options,
PQExpBuffer errorMessage)
{
int port = LDAP_DEF_PORT,
scope,
rc,
size,
state,
oldstate,
i;
#ifndef WIN32
int msgid;
#endif
bool found_keyword;
char *url,
*hostname,
*portstr,
*endptr,
*dn,
*scopestr,
*filter,
*result,
*p,
*p1 = NULL,
*optname = NULL,
*optval = NULL;
char *attrs[2] = {NULL, NULL};
LDAP *ld = NULL;
LDAPMessage *res,
*entry;
struct berval **values;
LDAP_TIMEVAL time = {PGLDAP_TIMEOUT, 0};
if ((url = strdup(purl)) == NULL)
{
printfPQExpBuffer(errorMessage, libpq_gettext("out of memory\n"));
return 3;
}
/*
* Parse URL components, check for correctness. Basically, url has '\0'
* placed at component boundaries and variables are pointed at each
* component.
*/
if (pg_strncasecmp(url, LDAP_URL, strlen(LDAP_URL)) != 0)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid LDAP URL \"%s\": scheme must be ldap://\n"), purl);
free(url);
return 3;
}
/* hostname */
hostname = url + strlen(LDAP_URL);
if (*hostname == '/') /* no hostname? */
hostname = DefaultHost; /* the default */
/* dn, "distinguished name" */
p = strchr(url + strlen(LDAP_URL), '/');
if (p == NULL || *(p + 1) == '\0' || *(p + 1) == '?')
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"invalid LDAP URL \"%s\": missing distinguished name\n"), purl);
free(url);
return 3;
}
*p = '\0'; /* terminate hostname */
dn = p + 1;
/* attribute */
if ((p = strchr(dn, '?')) == NULL || *(p + 1) == '\0' || *(p + 1) == '?')
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"invalid LDAP URL \"%s\": must have exactly one attribute\n"), purl);
free(url);
return 3;
}
*p = '\0';
attrs[0] = p + 1;
/* scope */
if ((p = strchr(attrs[0], '?')) == NULL || *(p + 1) == '\0' || *(p + 1) == '?')
{
printfPQExpBuffer(errorMessage, libpq_gettext("invalid LDAP URL \"%s\": must have search scope (base/one/sub)\n"), purl);
free(url);
return 3;
}
*p = '\0';
scopestr = p + 1;
/* filter */
if ((p = strchr(scopestr, '?')) == NULL || *(p + 1) == '\0' || *(p + 1) == '?')
{
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid LDAP URL \"%s\": no filter\n"), purl);
free(url);
return 3;
}
*p = '\0';
filter = p + 1;
if ((p = strchr(filter, '?')) != NULL)
*p = '\0';
/* port number? */
if ((p1 = strchr(hostname, ':')) != NULL)
{
long lport;
*p1 = '\0';
portstr = p1 + 1;
errno = 0;
lport = strtol(portstr, &endptr, 10);
if (*portstr == '\0' || *endptr != '\0' || errno || lport < 0 || lport > 65535)
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"invalid LDAP URL \"%s\": invalid port number\n"), purl);
free(url);
return 3;
}
port = (int) lport;
}
/* Allow only one attribute */
if (strchr(attrs[0], ',') != NULL)
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"invalid LDAP URL \"%s\": must have exactly one attribute\n"), purl);
free(url);
return 3;
}
/* set scope */
if (pg_strcasecmp(scopestr, "base") == 0)
scope = LDAP_SCOPE_BASE;
else if (pg_strcasecmp(scopestr, "one") == 0)
scope = LDAP_SCOPE_ONELEVEL;
else if (pg_strcasecmp(scopestr, "sub") == 0)
scope = LDAP_SCOPE_SUBTREE;
else
{
printfPQExpBuffer(errorMessage, libpq_gettext("invalid LDAP URL \"%s\": must have search scope (base/one/sub)\n"), purl);
free(url);
return 3;
}
/* initialize LDAP structure */
if ((ld = ldap_init(hostname, port)) == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("could not create LDAP structure\n"));
free(url);
return 3;
}
/*
* Perform an explicit anonymous bind.
*
* LDAP does not require that an anonymous bind is performed explicitly,
* but we want to distinguish between the case where LDAP bind does not
* succeed within PGLDAP_TIMEOUT seconds (return 2 to continue parsing the
* service control file) and the case where querying the LDAP server fails
* (return 1 to end parsing).
*
* Unfortunately there is no way of setting a timeout that works for both
* Windows and OpenLDAP.
*/
#ifdef WIN32
/* the nonstandard ldap_connect function performs an anonymous bind */
if (ldap_connect(ld, &time) != LDAP_SUCCESS)
{
/* error or timeout in ldap_connect */
free(url);
ldap_unbind(ld);
return 2;
}
#else /* !WIN32 */
/* in OpenLDAP, use the LDAP_OPT_NETWORK_TIMEOUT option */
if (ldap_set_option(ld, LDAP_OPT_NETWORK_TIMEOUT, &time) != LDAP_SUCCESS)
{
free(url);
ldap_unbind(ld);
return 3;
}
/* anonymous bind */
if ((msgid = ldap_simple_bind(ld, NULL, NULL)) == -1)
{
/* error or network timeout */
free(url);
ldap_unbind(ld);
return 2;
}
/* wait some time for the connection to succeed */
res = NULL;
if ((rc = ldap_result(ld, msgid, LDAP_MSG_ALL, &time, &res)) == -1 ||
res == NULL)
{
/* error or timeout */
if (res != NULL)
ldap_msgfree(res);
free(url);
ldap_unbind(ld);
return 2;
}
ldap_msgfree(res);
/* reset timeout */
time.tv_sec = -1;
if (ldap_set_option(ld, LDAP_OPT_NETWORK_TIMEOUT, &time) != LDAP_SUCCESS)
{
free(url);
ldap_unbind(ld);
return 3;
}
#endif /* WIN32 */
/* search */
res = NULL;
if ((rc = ldap_search_st(ld, dn, scope, filter, attrs, 0, &time, &res))
!= LDAP_SUCCESS)
{
if (res != NULL)
ldap_msgfree(res);
printfPQExpBuffer(errorMessage,
libpq_gettext("lookup on LDAP server failed: %s\n"),
ldap_err2string(rc));
ldap_unbind(ld);
free(url);
return 1;
}
/* complain if there was not exactly one result */
if ((rc = ldap_count_entries(ld, res)) != 1)
{
printfPQExpBuffer(errorMessage,
rc ? libpq_gettext("more than one entry found on LDAP lookup\n")
: libpq_gettext("no entry found on LDAP lookup\n"));
ldap_msgfree(res);
ldap_unbind(ld);
free(url);
return 1;
}
/* get entry */
if ((entry = ldap_first_entry(ld, res)) == NULL)
{
/* should never happen */
printfPQExpBuffer(errorMessage,
libpq_gettext("no entry found on LDAP lookup\n"));
ldap_msgfree(res);
ldap_unbind(ld);
free(url);
return 1;
}
/* get values */
if ((values = ldap_get_values_len(ld, entry, attrs[0])) == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("attribute has no values on LDAP lookup\n"));
ldap_msgfree(res);
ldap_unbind(ld);
free(url);
return 1;
}
ldap_msgfree(res);
free(url);
if (values[0] == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("attribute has no values on LDAP lookup\n"));
ldap_value_free_len(values);
ldap_unbind(ld);
return 1;
}
/* concatenate values into a single string with newline terminators */
size = 1; /* for the trailing null */
for (i = 0; values[i] != NULL; i++)
size += values[i]->bv_len + 1;
if ((result = malloc(size)) == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
ldap_value_free_len(values);
ldap_unbind(ld);
return 3;
}
p = result;
for (i = 0; values[i] != NULL; i++)
{
memcpy(p, values[i]->bv_val, values[i]->bv_len);
p += values[i]->bv_len;
*(p++) = '\n';
}
*p = '\0';
ldap_value_free_len(values);
ldap_unbind(ld);
/* parse result string */
oldstate = state = 0;
for (p = result; *p != '\0'; ++p)
{
switch (state)
{
case 0: /* between entries */
if (!ld_is_sp_tab(*p) && !ld_is_nl_cr(*p))
{
optname = p;
state = 1;
}
break;
case 1: /* in option name */
if (ld_is_sp_tab(*p))
{
*p = '\0';
state = 2;
}
else if (ld_is_nl_cr(*p))
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"missing \"=\" after \"%s\" in connection info string\n"),
optname);
free(result);
return 3;
}
else if (*p == '=')
{
*p = '\0';
state = 3;
}
break;
case 2: /* after option name */
if (*p == '=')
{
state = 3;
}
else if (!ld_is_sp_tab(*p))
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"missing \"=\" after \"%s\" in connection info string\n"),
optname);
free(result);
return 3;
}
break;
case 3: /* before option value */
if (*p == '\'')
{
optval = p + 1;
p1 = p + 1;
state = 5;
}
else if (ld_is_nl_cr(*p))
{
optval = optname + strlen(optname); /* empty */
state = 0;
}
else if (!ld_is_sp_tab(*p))
{
optval = p;
state = 4;
}
break;
case 4: /* in unquoted option value */
if (ld_is_sp_tab(*p) || ld_is_nl_cr(*p))
{
*p = '\0';
state = 0;
}
break;
case 5: /* in quoted option value */
if (*p == '\'')
{
*p1 = '\0';
state = 0;
}
else if (*p == '\\')
state = 6;
else
*(p1++) = *p;
break;
case 6: /* in quoted option value after escape */
*(p1++) = *p;
state = 5;
break;
}
if (state == 0 && oldstate != 0)
{
found_keyword = false;
for (i = 0; options[i].keyword; i++)
{
if (strcmp(options[i].keyword, optname) == 0)
{
if (options[i].val == NULL)
{
options[i].val = strdup(optval);
if (!options[i].val)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
free(result);
return 3;
}
}
found_keyword = true;
break;
}
}
if (!found_keyword)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid connection option \"%s\"\n"),
optname);
free(result);
return 1;
}
optname = NULL;
optval = NULL;
}
oldstate = state;
}
free(result);
if (state == 5 || state == 6)
{
printfPQExpBuffer(errorMessage, libpq_gettext(
"unterminated quoted string in connection info string\n"));
return 3;
}
return 0;
}
#endif /* USE_LDAP */
#define MAXBUFSIZE 256
/*
* parseServiceInfo: if a service name has been given, look it up and absorb
* connection options from it into *options.
*
* Returns 0 on success, nonzero on failure. On failure, if errorMessage
* isn't null, also store an error message there. (Note: the only reason
* this function and related ones don't dump core on errorMessage == NULL
* is the undocumented fact that printfPQExpBuffer does nothing when passed
* a null PQExpBuffer pointer.)
*/
static int
parseServiceInfo(PQconninfoOption *options, PQExpBuffer errorMessage)
{
const char *service = conninfo_getval(options, "service");
char serviceFile[MAXPGPATH];
char *env;
bool group_found = false;
int status;
struct stat stat_buf;
/*
* We have to special-case the environment variable PGSERVICE here, since
* this is and should be called before inserting environment defaults for
* other connection options.
*/
if (service == NULL)
service = getenv("PGSERVICE");
/* If no service name given, nothing to do */
if (service == NULL)
return 0;
/*
* Try PGSERVICEFILE if specified, else try ~/.pg_service.conf (if that
* exists).
*/
if ((env = getenv("PGSERVICEFILE")) != NULL)
strlcpy(serviceFile, env, sizeof(serviceFile));
else
{
char homedir[MAXPGPATH];
if (!pqGetHomeDirectory(homedir, sizeof(homedir)))
goto next_file;
snprintf(serviceFile, MAXPGPATH, "%s/%s", homedir, ".pg_service.conf");
if (stat(serviceFile, &stat_buf) != 0)
goto next_file;
}
status = parseServiceFile(serviceFile, service, options, errorMessage, &group_found);
if (group_found || status != 0)
return status;
next_file:
/*
* This could be used by any application so we can't use the binary
* location to find our config files.
*/
snprintf(serviceFile, MAXPGPATH, "%s/pg_service.conf",
getenv("PGSYSCONFDIR") ? getenv("PGSYSCONFDIR") : SYSCONFDIR);
if (stat(serviceFile, &stat_buf) != 0)
goto last_file;
status = parseServiceFile(serviceFile, service, options, errorMessage, &group_found);
if (status != 0)
return status;
last_file:
if (!group_found)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("definition of service \"%s\" not found\n"), service);
return 3;
}
return 0;
}
static int
parseServiceFile(const char *serviceFile,
const char *service,
PQconninfoOption *options,
PQExpBuffer errorMessage,
bool *group_found)
{
int linenr = 0,
i;
FILE *f;
char buf[MAXBUFSIZE],
*line;
f = fopen(serviceFile, "r");
if (f == NULL)
{
printfPQExpBuffer(errorMessage, libpq_gettext("service file \"%s\" not found\n"),
serviceFile);
return 1;
}
while ((line = fgets(buf, sizeof(buf), f)) != NULL)
{
int len;
linenr++;
if (strlen(line) >= sizeof(buf) - 1)
{
fclose(f);
printfPQExpBuffer(errorMessage,
libpq_gettext("line %d too long in service file \"%s\"\n"),
linenr,
serviceFile);
return 2;
}
/* ignore whitespace at end of line, especially the newline */
len = strlen(line);
while (len > 0 && isspace((unsigned char) line[len - 1]))
line[--len] = '\0';
/* ignore leading whitespace too */
while (*line && isspace((unsigned char) line[0]))
line++;
/* ignore comments and empty lines */
if (line[0] == '\0' || line[0] == '#')
continue;
/* Check for right groupname */
if (line[0] == '[')
{
if (*group_found)
{
/* group info already read */
fclose(f);
return 0;
}
if (strncmp(line + 1, service, strlen(service)) == 0 &&
line[strlen(service) + 1] == ']')
*group_found = true;
else
*group_found = false;
}
else
{
if (*group_found)
{
/*
* Finally, we are in the right group and can parse the line
*/
char *key,
*val;
bool found_keyword;
#ifdef USE_LDAP
if (strncmp(line, "ldap", 4) == 0)
{
int rc = ldapServiceLookup(line, options, errorMessage);
/* if rc = 2, go on reading for fallback */
switch (rc)
{
case 0:
fclose(f);
return 0;
case 1:
case 3:
fclose(f);
return 3;
case 2:
continue;
}
}
#endif
key = line;
val = strchr(line, '=');
if (val == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("syntax error in service file \"%s\", line %d\n"),
serviceFile,
linenr);
fclose(f);
return 3;
}
*val++ = '\0';
if (strcmp(key, "service") == 0)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("nested service specifications not supported in service file \"%s\", line %d\n"),
serviceFile,
linenr);
fclose(f);
return 3;
}
/*
* Set the parameter --- but don't override any previous
* explicit setting.
*/
found_keyword = false;
for (i = 0; options[i].keyword; i++)
{
if (strcmp(options[i].keyword, key) == 0)
{
if (options[i].val == NULL)
options[i].val = strdup(val);
if (!options[i].val)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
fclose(f);
return 3;
}
found_keyword = true;
break;
}
}
if (!found_keyword)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("syntax error in service file \"%s\", line %d\n"),
serviceFile,
linenr);
fclose(f);
return 3;
}
}
}
}
fclose(f);
return 0;
}
/*
* PQconninfoParse
*
* Parse a string like PQconnectdb() would do and return the
* resulting connection options array. NULL is returned on failure.
* The result contains only options specified directly in the string,
* not any possible default values.
*
* If errmsg isn't NULL, *errmsg is set to NULL on success, or a malloc'd
* string on failure (use PQfreemem to free it). In out-of-memory conditions
* both *errmsg and the result could be NULL.
*
* NOTE: the returned array is dynamically allocated and should
* be freed when no longer needed via PQconninfoFree().
*/
PQconninfoOption *
PQconninfoParse(const char *conninfo, char **errmsg)
{
PQExpBufferData errorBuf;
PQconninfoOption *connOptions;
if (errmsg)
*errmsg = NULL; /* default */
initPQExpBuffer(&errorBuf);
if (PQExpBufferDataBroken(errorBuf))
return NULL; /* out of memory already :-( */
connOptions = parse_connection_string(conninfo, &errorBuf, false);
if (connOptions == NULL && errmsg)
*errmsg = errorBuf.data;
else
termPQExpBuffer(&errorBuf);
return connOptions;
}
/*
* Build a working copy of the constant PQconninfoOptions array.
*/
static PQconninfoOption *
conninfo_init(PQExpBuffer errorMessage)
{
PQconninfoOption *options;
PQconninfoOption *opt_dest;
const internalPQconninfoOption *cur_opt;
/*
* Get enough memory for all options in PQconninfoOptions, even if some
* end up being filtered out.
*/
options = (PQconninfoOption *) malloc(sizeof(PQconninfoOption) * sizeof(PQconninfoOptions) / sizeof(PQconninfoOptions[0]));
if (options == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
return NULL;
}
opt_dest = options;
for (cur_opt = PQconninfoOptions; cur_opt->keyword; cur_opt++)
{
/* Only copy the public part of the struct, not the full internal */
memcpy(opt_dest, cur_opt, sizeof(PQconninfoOption));
opt_dest++;
}
MemSet(opt_dest, 0, sizeof(PQconninfoOption));
return options;
}
/*
* Connection string parser
*
* Returns a malloc'd PQconninfoOption array, if parsing is successful.
* Otherwise, NULL is returned and an error message is left in errorMessage.
*
* If use_defaults is true, default values are filled in (from a service file,
* environment variables, etc).
*/
static PQconninfoOption *
parse_connection_string(const char *connstr, PQExpBuffer errorMessage,
bool use_defaults)
{
/* Parse as URI if connection string matches URI prefix */
if (uri_prefix_length(connstr) != 0)
return conninfo_uri_parse(connstr, errorMessage, use_defaults);
/* Parse as default otherwise */
return conninfo_parse(connstr, errorMessage, use_defaults);
}
/*
* Checks if connection string starts with either of the valid URI prefix
* designators.
*
* Returns the URI prefix length, 0 if the string doesn't contain a URI prefix.
*
* XXX this is duplicated in psql/common.c.
*/
static int
uri_prefix_length(const char *connstr)
{
if (strncmp(connstr, uri_designator,
sizeof(uri_designator) - 1) == 0)
return sizeof(uri_designator) - 1;
if (strncmp(connstr, short_uri_designator,
sizeof(short_uri_designator) - 1) == 0)
return sizeof(short_uri_designator) - 1;
return 0;
}
/*
* Recognized connection string either starts with a valid URI prefix or
* contains a "=" in it.
*
* Must be consistent with parse_connection_string: anything for which this
* returns true should at least look like it's parseable by that routine.
*
* XXX this is duplicated in psql/common.c
*/
static bool
recognized_connection_string(const char *connstr)
{
return uri_prefix_length(connstr) != 0 || strchr(connstr, '=') != NULL;
}
/*
* Subroutine for parse_connection_string
*
* Deal with a string containing key=value pairs.
*/
static PQconninfoOption *
conninfo_parse(const char *conninfo, PQExpBuffer errorMessage,
bool use_defaults)
{
char *pname;
char *pval;
char *buf;
char *cp;
char *cp2;
PQconninfoOption *options;
/* Make a working copy of PQconninfoOptions */
options = conninfo_init(errorMessage);
if (options == NULL)
return NULL;
/* Need a modifiable copy of the input string */
if ((buf = strdup(conninfo)) == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
PQconninfoFree(options);
return NULL;
}
cp = buf;
while (*cp)
{
/* Skip blanks before the parameter name */
if (isspace((unsigned char) *cp))
{
cp++;
continue;
}
/* Get the parameter name */
pname = cp;
while (*cp)
{
if (*cp == '=')
break;
if (isspace((unsigned char) *cp))
{
*cp++ = '\0';
while (*cp)
{
if (!isspace((unsigned char) *cp))
break;
cp++;
}
break;
}
cp++;
}
/* Check that there is a following '=' */
if (*cp != '=')
{
printfPQExpBuffer(errorMessage,
libpq_gettext("missing \"=\" after \"%s\" in connection info string\n"),
pname);
PQconninfoFree(options);
free(buf);
return NULL;
}
*cp++ = '\0';
/* Skip blanks after the '=' */
while (*cp)
{
if (!isspace((unsigned char) *cp))
break;
cp++;
}
/* Get the parameter value */
pval = cp;
if (*cp != '\'')
{
cp2 = pval;
while (*cp)
{
if (isspace((unsigned char) *cp))
{
*cp++ = '\0';
break;
}
if (*cp == '\\')
{
cp++;
if (*cp != '\0')
*cp2++ = *cp++;
}
else
*cp2++ = *cp++;
}
*cp2 = '\0';
}
else
{
cp2 = pval;
cp++;
for (;;)
{
if (*cp == '\0')
{
printfPQExpBuffer(errorMessage,
libpq_gettext("unterminated quoted string in connection info string\n"));
PQconninfoFree(options);
free(buf);
return NULL;
}
if (*cp == '\\')
{
cp++;
if (*cp != '\0')
*cp2++ = *cp++;
continue;
}
if (*cp == '\'')
{
*cp2 = '\0';
cp++;
break;
}
*cp2++ = *cp++;
}
}
/*
* Now that we have the name and the value, store the record.
*/
if (!conninfo_storeval(options, pname, pval, errorMessage, false, false))
{
PQconninfoFree(options);
free(buf);
return NULL;
}
}
/* Done with the modifiable input string */
free(buf);
/*
* Add in defaults if the caller wants that.
*/
if (use_defaults)
{
if (!conninfo_add_defaults(options, errorMessage))
{
PQconninfoFree(options);
return NULL;
}
}
return options;
}
/*
* Conninfo array parser routine
*
* If successful, a malloc'd PQconninfoOption array is returned.
* If not successful, NULL is returned and an error message is
* left in errorMessage.
* Defaults are supplied (from a service file, environment variables, etc)
* for unspecified options, but only if use_defaults is true.
*
* If expand_dbname is non-zero, and the value passed for the first occurrence
* of "dbname" keyword is a connection string (as indicated by
* recognized_connection_string) then parse and process it, overriding any
* previously processed conflicting keywords. Subsequent keywords will take
* precedence, however. In-tree programs generally specify expand_dbname=true,
* so command-line arguments naming a database can use a connection string.
* Some code acquires arbitrary database names from known-literal sources like
* PQdb(), PQconninfoParse() and pg_database.datname. When connecting to such
* a database, in-tree code first wraps the name in a connection string.
*/
static PQconninfoOption *
conninfo_array_parse(const char *const *keywords, const char *const *values,
PQExpBuffer errorMessage, bool use_defaults,
int expand_dbname)
{
PQconninfoOption *options;
PQconninfoOption *dbname_options = NULL;
PQconninfoOption *option;
int i = 0;
/*
* If expand_dbname is non-zero, check keyword "dbname" to see if val is
* actually a recognized connection string.
*/
while (expand_dbname && keywords[i])
{
const char *pname = keywords[i];
const char *pvalue = values[i];
/* first find "dbname" if any */
if (strcmp(pname, "dbname") == 0 && pvalue)
{
/*
* If value is a connection string, parse it, but do not use
* defaults here -- those get picked up later. We only want to
* override for those parameters actually passed.
*/
if (recognized_connection_string(pvalue))
{
dbname_options = parse_connection_string(pvalue, errorMessage, false);
if (dbname_options == NULL)
return NULL;
}
break;
}
++i;
}
/* Make a working copy of PQconninfoOptions */
options = conninfo_init(errorMessage);
if (options == NULL)
{
PQconninfoFree(dbname_options);
return NULL;
}
/* Parse the keywords/values arrays */
i = 0;
while (keywords[i])
{
const char *pname = keywords[i];
const char *pvalue = values[i];
if (pvalue != NULL && pvalue[0] != '\0')
{
/* Search for the param record */
for (option = options; option->keyword != NULL; option++)
{
if (strcmp(option->keyword, pname) == 0)
break;
}
/* Check for invalid connection option */
if (option->keyword == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid connection option \"%s\"\n"),
pname);
PQconninfoFree(options);
PQconninfoFree(dbname_options);
return NULL;
}
/*
* If we are on the first dbname parameter, and we have a parsed
* connection string, copy those parameters across, overriding any
* existing previous settings.
*/
if (strcmp(pname, "dbname") == 0 && dbname_options)
{
PQconninfoOption *str_option;
for (str_option = dbname_options; str_option->keyword != NULL; str_option++)
{
if (str_option->val != NULL)
{
int k;
for (k = 0; options[k].keyword; k++)
{
if (strcmp(options[k].keyword, str_option->keyword) == 0)
{
if (options[k].val)
free(options[k].val);
options[k].val = strdup(str_option->val);
if (!options[k].val)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
PQconninfoFree(options);
PQconninfoFree(dbname_options);
return NULL;
}
break;
}
}
}
}
/*
* Forget the parsed connection string, so that any subsequent
* dbname parameters will not be expanded.
*/
PQconninfoFree(dbname_options);
dbname_options = NULL;
}
else
{
/*
* Store the value, overriding previous settings
*/
if (option->val)
free(option->val);
option->val = strdup(pvalue);
if (!option->val)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
PQconninfoFree(options);
PQconninfoFree(dbname_options);
return NULL;
}
}
}
++i;
}
PQconninfoFree(dbname_options);
/*
* Add in defaults if the caller wants that.
*/
if (use_defaults)
{
if (!conninfo_add_defaults(options, errorMessage))
{
PQconninfoFree(options);
return NULL;
}
}
return options;
}
/*
* Add the default values for any unspecified options to the connection
* options array.
*
* Defaults are obtained from a service file, environment variables, etc.
*
* Returns true if successful, otherwise false; errorMessage, if supplied,
* is filled in upon failure. Note that failure to locate a default value
* is not an error condition here --- we just leave the option's value as
* NULL.
*/
static bool
conninfo_add_defaults(PQconninfoOption *options, PQExpBuffer errorMessage)
{
PQconninfoOption *option;
char *tmp;
/*
* If there's a service spec, use it to obtain any not-explicitly-given
* parameters. Ignore error if no error message buffer is passed because
* there is no way to pass back the failure message.
*/
if (parseServiceInfo(options, errorMessage) != 0 && errorMessage)
return false;
/*
* Get the fallback resources for parameters not specified in the conninfo
* string nor the service.
*/
for (option = options; option->keyword != NULL; option++)
{
if (option->val != NULL)
continue; /* Value was in conninfo or service */
/*
* Try to get the environment variable fallback
*/
if (option->envvar != NULL)
{
if ((tmp = getenv(option->envvar)) != NULL)
{
option->val = strdup(tmp);
if (!option->val)
{
if (errorMessage)
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
continue;
}
}
/*
* Interpret the deprecated PGREQUIRESSL environment variable. Per
* tradition, translate values starting with "1" to sslmode=require,
* and ignore other values. Given both PGREQUIRESSL=1 and PGSSLMODE,
* PGSSLMODE takes precedence; the opposite was true before v9.3.
*/
if (strcmp(option->keyword, "sslmode") == 0)
{
const char *requiresslenv = getenv("PGREQUIRESSL");
if (requiresslenv != NULL && requiresslenv[0] == '1')
{
option->val = strdup("require");
if (!option->val)
{
if (errorMessage)
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
continue;
}
}
/*
* No environment variable specified or the variable isn't set - try
* compiled-in default
*/
if (option->compiled != NULL)
{
option->val = strdup(option->compiled);
if (!option->val)
{
if (errorMessage)
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
return false;
}
continue;
}
/*
* Special handling for "user" option. Note that if pg_fe_getauthname
* fails, we just leave the value as NULL; there's no need for this to
* be an error condition if the caller provides a user name. The only
* reason we do this now at all is so that callers of PQconndefaults
* will see a correct default (barring error, of course).
*/
if (strcmp(option->keyword, "user") == 0)
{
option->val = pg_fe_getauthname(NULL);
continue;
}
}
return true;
}
/*
* Subroutine for parse_connection_string
*
* Deal with a URI connection string.
*/
static PQconninfoOption *
conninfo_uri_parse(const char *uri, PQExpBuffer errorMessage,
bool use_defaults)
{
PQconninfoOption *options;
/* Make a working copy of PQconninfoOptions */
options = conninfo_init(errorMessage);
if (options == NULL)
return NULL;
if (!conninfo_uri_parse_options(options, uri, errorMessage))
{
PQconninfoFree(options);
return NULL;
}
/*
* Add in defaults if the caller wants that.
*/
if (use_defaults)
{
if (!conninfo_add_defaults(options, errorMessage))
{
PQconninfoFree(options);
return NULL;
}
}
return options;
}
/*
* conninfo_uri_parse_options
* Actual URI parser.
*
* If successful, returns true while the options array is filled with parsed
* options from the URI.
* If not successful, returns false and fills errorMessage accordingly.
*
* Parses the connection URI string in 'uri' according to the URI syntax (RFC
* 3986):
*
* postgresql://[user[:password]@][netloc][:port][/dbname][?param1=value1&...]
*
* where "netloc" is a hostname, an IPv4 address, or an IPv6 address surrounded
* by literal square brackets. As an extension, we also allow multiple
* netloc[:port] specifications, separated by commas:
*
* postgresql://[user[:password]@][netloc][:port][,...][/dbname][?param1=value1&...]
*
* Any of the URI parts might use percent-encoding (%xy).
*/
static bool
conninfo_uri_parse_options(PQconninfoOption *options, const char *uri,
PQExpBuffer errorMessage)
{
int prefix_len;
char *p;
char *buf = NULL;
char *start;
char prevchar = '\0';
char *user = NULL;
char *host = NULL;
bool retval = false;
PQExpBufferData hostbuf;
PQExpBufferData portbuf;
initPQExpBuffer(&hostbuf);
initPQExpBuffer(&portbuf);
if (PQExpBufferDataBroken(hostbuf) || PQExpBufferDataBroken(portbuf))
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
goto cleanup;
}
/* need a modifiable copy of the input URI */
buf = strdup(uri);
if (buf == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("out of memory\n"));
goto cleanup;
}
start = buf;
/* Skip the URI prefix */
prefix_len = uri_prefix_length(uri);
if (prefix_len == 0)
{
/* Should never happen */
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid URI propagated to internal parser routine: \"%s\"\n"),
uri);
goto cleanup;
}
start += prefix_len;
p = start;
/* Look ahead for possible user credentials designator */
while (*p && *p != '@' && *p != '/')
++p;
if (*p == '@')
{
/*
* Found username/password designator, so URI should be of the form
* "scheme://user[:password]@[netloc]".
*/
user = start;
p = user;
while (*p != ':' && *p != '@')
++p;
/* Save last char and cut off at end of user name */
prevchar = *p;
*p = '\0';
if (*user &&
!conninfo_storeval(options, "user", user,
errorMessage, false, true))
goto cleanup;
if (prevchar == ':')
{
const char *password = p + 1;
while (*p != '@')
++p;
*p = '\0';
if (*password &&
!conninfo_storeval(options, "password", password,
errorMessage, false, true))
goto cleanup;
}
/* Advance past end of parsed user name or password token */
++p;
}
else
{
/*
* No username/password designator found. Reset to start of URI.
*/
p = start;
}
/*
* There may be multiple netloc[:port] pairs, each separated from the next
* by a comma. When we initially enter this loop, "p" has been
* incremented past optional URI credential information at this point and
* now points at the "netloc" part of the URI. On subsequent loop
* iterations, "p" has been incremented past the comma separator and now
* points at the start of the next "netloc".
*/
for (;;)
{
/*
* Look for IPv6 address.
*/
if (*p == '[')
{
host = ++p;
while (*p && *p != ']')
++p;
if (!*p)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("end of string reached when looking for matching \"]\" in IPv6 host address in URI: \"%s\"\n"),
uri);
goto cleanup;
}
if (p == host)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("IPv6 host address may not be empty in URI: \"%s\"\n"),
uri);
goto cleanup;
}
/* Cut off the bracket and advance */
*(p++) = '\0';
/*
* The address may be followed by a port specifier or a slash or a
* query or a separator comma.
*/
if (*p && *p != ':' && *p != '/' && *p != '?' && *p != ',')
{
printfPQExpBuffer(errorMessage,
libpq_gettext("unexpected character \"%c\" at position %d in URI (expected \":\" or \"/\"): \"%s\"\n"),
*p, (int) (p - buf + 1), uri);
goto cleanup;
}
}
else
{
/* not an IPv6 address: DNS-named or IPv4 netloc */
host = p;
/*
* Look for port specifier (colon) or end of host specifier
* (slash) or query (question mark) or host separator (comma).
*/
while (*p && *p != ':' && *p != '/' && *p != '?' && *p != ',')
++p;
}
/* Save the hostname terminator before we null it */
prevchar = *p;
*p = '\0';
appendPQExpBufferStr(&hostbuf, host);
if (prevchar == ':')
{
const char *port = ++p; /* advance past host terminator */
while (*p && *p != '/' && *p != '?' && *p != ',')
++p;
prevchar = *p;
*p = '\0';
appendPQExpBufferStr(&portbuf, port);
}
if (prevchar != ',')
break;
++p; /* advance past comma separator */
appendPQExpBufferChar(&hostbuf, ',');
appendPQExpBufferChar(&portbuf, ',');
}
/* Save final values for host and port. */
if (PQExpBufferDataBroken(hostbuf) || PQExpBufferDataBroken(portbuf))
goto cleanup;
if (hostbuf.data[0] &&
!conninfo_storeval(options, "host", hostbuf.data,
errorMessage, false, true))
goto cleanup;
if (portbuf.data[0] &&
!conninfo_storeval(options, "port", portbuf.data,
errorMessage, false, true))
goto cleanup;
if (prevchar && prevchar != '?')
{
const char *dbname = ++p; /* advance past host terminator */
/* Look for query parameters */
while (*p && *p != '?')
++p;
prevchar = *p;
*p = '\0';
/*
* Avoid setting dbname to an empty string, as it forces the default
* value (username) and ignores $PGDATABASE, as opposed to not setting
* it at all.
*/
if (*dbname &&
!conninfo_storeval(options, "dbname", dbname,
errorMessage, false, true))
goto cleanup;
}
if (prevchar)
{
++p; /* advance past terminator */
if (!conninfo_uri_parse_params(p, options, errorMessage))
goto cleanup;
}
/* everything parsed okay */
retval = true;
cleanup:
termPQExpBuffer(&hostbuf);
termPQExpBuffer(&portbuf);
if (buf)
free(buf);
return retval;
}
/*
* Connection URI parameters parser routine
*
* If successful, returns true while connOptions is filled with parsed
* parameters. Otherwise, returns false and fills errorMessage appropriately.
*
* Destructively modifies 'params' buffer.
*/
static bool
conninfo_uri_parse_params(char *params,
PQconninfoOption *connOptions,
PQExpBuffer errorMessage)
{
while (*params)
{
char *keyword = params;
char *value = NULL;
char *p = params;
bool malloced = false;
/*
* Scan the params string for '=' and '&', marking the end of keyword
* and value respectively.
*/
for (;;)
{
if (*p == '=')
{
/* Was there '=' already? */
if (value != NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("extra key/value separator \"=\" in URI query parameter: \"%s\"\n"),
keyword);
return false;
}
/* Cut off keyword, advance to value */
*p++ = '\0';
value = p;
}
else if (*p == '&' || *p == '\0')
{
/*
* If not at the end, cut off value and advance; leave p
* pointing to start of the next parameter, if any.
*/
if (*p != '\0')
*p++ = '\0';
/* Was there '=' at all? */
if (value == NULL)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("missing key/value separator \"=\" in URI query parameter: \"%s\"\n"),
keyword);
return false;
}
/* Got keyword and value, go process them. */
break;
}
else
++p; /* Advance over all other bytes. */
}
keyword = conninfo_uri_decode(keyword, errorMessage);
if (keyword == NULL)
{
/* conninfo_uri_decode already set an error message */
return false;
}
value = conninfo_uri_decode(value, errorMessage);
if (value == NULL)
{
/* conninfo_uri_decode already set an error message */
free(keyword);
return false;
}
malloced = true;
/*
* Special keyword handling for improved JDBC compatibility.
*/
if (strcmp(keyword, "ssl") == 0 &&
strcmp(value, "true") == 0)
{
free(keyword);
free(value);
malloced = false;
keyword = "sslmode";
value = "require";
}
/*
* Store the value if the corresponding option exists; ignore
* otherwise. At this point both keyword and value are not
* URI-encoded.
*/
if (!conninfo_storeval(connOptions, keyword, value,
errorMessage, true, false))
{
/* Insert generic message if conninfo_storeval didn't give one. */
if (errorMessage->len == 0)
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid URI query parameter: \"%s\"\n"),
keyword);
/* And fail. */
if (malloced)
{
free(keyword);
free(value);
}
return false;
}
if (malloced)
{
free(keyword);
free(value);
}
/* Proceed to next key=value pair, if any */
params = p;
}
return true;
}
/*
* Connection URI decoder routine
*
* If successful, returns the malloc'd decoded string.
* If not successful, returns NULL and fills errorMessage accordingly.
*
* The string is decoded by replacing any percent-encoded tokens with
* corresponding characters, while preserving any non-encoded characters. A
* percent-encoded token is a character triplet: a percent sign, followed by a
* pair of hexadecimal digits (0-9A-F), where lower- and upper-case letters are
* treated identically.
*/
static char *
conninfo_uri_decode(const char *str, PQExpBuffer errorMessage)
{
char *buf;
char *p;
const char *q = str;
buf = malloc(strlen(str) + 1);
if (buf == NULL)
{
printfPQExpBuffer(errorMessage, libpq_gettext("out of memory\n"));
return NULL;
}
p = buf;
for (;;)
{
if (*q != '%')
{
/* copy and check for NUL terminator */
if (!(*(p++) = *(q++)))
break;
}
else
{
int hi;
int lo;
int c;
++q; /* skip the percent sign itself */
/*
* Possible EOL will be caught by the first call to
* get_hexdigit(), so we never dereference an invalid q pointer.
*/
if (!(get_hexdigit(*q++, &hi) && get_hexdigit(*q++, &lo)))
{
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid percent-encoded token: \"%s\"\n"),
str);
free(buf);
return NULL;
}
c = (hi << 4) | lo;
if (c == 0)
{
printfPQExpBuffer(errorMessage,
libpq_gettext("forbidden value %%00 in percent-encoded value: \"%s\"\n"),
str);
free(buf);
return NULL;
}
*(p++) = c;
}
}
return buf;
}
/*
* Convert hexadecimal digit character to its integer value.
*
* If successful, returns true and value is filled with digit's base 16 value.
* If not successful, returns false.
*
* Lower- and upper-case letters in the range A-F are treated identically.
*/
static bool
get_hexdigit(char digit, int *value)
{
if ('0' <= digit && digit <= '9')
*value = digit - '0';
else if ('A' <= digit && digit <= 'F')
*value = digit - 'A' + 10;
else if ('a' <= digit && digit <= 'f')
*value = digit - 'a' + 10;
else
return false;
return true;
}
/*
* Find an option value corresponding to the keyword in the connOptions array.
*
* If successful, returns a pointer to the corresponding option's value.
* If not successful, returns NULL.
*/
static const char *
conninfo_getval(PQconninfoOption *connOptions,
const char *keyword)
{
PQconninfoOption *option;
option = conninfo_find(connOptions, keyword);
return option ? option->val : NULL;
}
/*
* Store a (new) value for an option corresponding to the keyword in
* connOptions array.
*
* If uri_decode is true, the value is URI-decoded. The keyword is always
* assumed to be non URI-encoded.
*
* If successful, returns a pointer to the corresponding PQconninfoOption,
* which value is replaced with a strdup'd copy of the passed value string.
* The existing value for the option is free'd before replacing, if any.
*
* If not successful, returns NULL and fills errorMessage accordingly.
* However, if the reason of failure is an invalid keyword being passed and
* ignoreMissing is true, errorMessage will be left untouched.
*/
static PQconninfoOption *
conninfo_storeval(PQconninfoOption *connOptions,
const char *keyword, const char *value,
PQExpBuffer errorMessage, bool ignoreMissing,
bool uri_decode)
{
PQconninfoOption *option;
char *value_copy;
/*
* For backwards compatibility, requiressl=1 gets translated to
* sslmode=require, and requiressl=0 gets translated to sslmode=prefer
* (which is the default for sslmode).
*/
if (strcmp(keyword, "requiressl") == 0)
{
keyword = "sslmode";
if (value[0] == '1')
value = "require";
else
value = "prefer";
}
option = conninfo_find(connOptions, keyword);
if (option == NULL)
{
if (!ignoreMissing)
printfPQExpBuffer(errorMessage,
libpq_gettext("invalid connection option \"%s\"\n"),
keyword);
return NULL;
}
if (uri_decode)
{
value_copy = conninfo_uri_decode(value, errorMessage);
if (value_copy == NULL)
/* conninfo_uri_decode already set an error message */
return NULL;
}
else
{
value_copy = strdup(value);
if (value_copy == NULL)
{
printfPQExpBuffer(errorMessage, libpq_gettext("out of memory\n"));
return NULL;
}
}
if (option->val)
free(option->val);
option->val = value_copy;
return option;
}
/*
* Find a PQconninfoOption option corresponding to the keyword in the
* connOptions array.
*
* If successful, returns a pointer to the corresponding PQconninfoOption
* structure.
* If not successful, returns NULL.
*/
static PQconninfoOption *
conninfo_find(PQconninfoOption *connOptions, const char *keyword)
{
PQconninfoOption *option;
for (option = connOptions; option->keyword != NULL; option++)
{
if (strcmp(option->keyword, keyword) == 0)
return option;
}
return NULL;
}
/*
* Return the connection options used for the connection
*/
PQconninfoOption *
PQconninfo(PGconn *conn)
{
PQExpBufferData errorBuf;
PQconninfoOption *connOptions;
if (conn == NULL)
return NULL;
/* We don't actually report any errors here, but callees want a buffer */
initPQExpBuffer(&errorBuf);
if (PQExpBufferDataBroken(errorBuf))
return NULL; /* out of memory already :-( */
connOptions = conninfo_init(&errorBuf);
if (connOptions != NULL)
{
const internalPQconninfoOption *option;
for (option = PQconninfoOptions; option->keyword; option++)
{
char **connmember;
if (option->connofs < 0)
continue;
connmember = (char **) ((char *) conn + option->connofs);
if (*connmember)
conninfo_storeval(connOptions, option->keyword, *connmember,
&errorBuf, true, false);
}
}
termPQExpBuffer(&errorBuf);
return connOptions;
}
void
PQconninfoFree(PQconninfoOption *connOptions)
{
PQconninfoOption *option;
if (connOptions == NULL)
return;
for (option = connOptions; option->keyword != NULL; option++)
{
if (option->val != NULL)
free(option->val);
}
free(connOptions);
}
/* =========== accessor functions for PGconn ========= */
char *
PQdb(const PGconn *conn)
{
if (!conn)
return NULL;
return conn->dbName;
}
char *
PQuser(const PGconn *conn)
{
if (!conn)
return NULL;
return conn->pguser;
}
char *
PQpass(const PGconn *conn)
{
char *password = NULL;
if (!conn)
return NULL;
if (conn->connhost != NULL)
password = conn->connhost[conn->whichhost].password;
if (password == NULL)
password = conn->pgpass;
/* Historically we've returned "" not NULL for no password specified */
if (password == NULL)
password = "";
return password;
}
char *
PQhost(const PGconn *conn)
{
if (!conn)
return NULL;
if (conn->connhost != NULL)
{
/*
* Return the verbatim host value provided by user, or hostaddr in its
* lack.
*/
if (conn->connhost[conn->whichhost].host != NULL &&
conn->connhost[conn->whichhost].host[0] != '\0')
return conn->connhost[conn->whichhost].host;
else if (conn->connhost[conn->whichhost].hostaddr != NULL &&
conn->connhost[conn->whichhost].hostaddr[0] != '\0')
return conn->connhost[conn->whichhost].hostaddr;
}
return "";
}
char *
PQhostaddr(const PGconn *conn)
{
if (!conn)
return NULL;
/* Return the parsed IP address */
if (conn->connhost != NULL && conn->connip != NULL)
return conn->connip;
return "";
}
char *
PQport(const PGconn *conn)
{
if (!conn)
return NULL;
if (conn->connhost != NULL)
return conn->connhost[conn->whichhost].port;
return "";
}
char *
PQtty(const PGconn *conn)
{
if (!conn)
return NULL;
return conn->pgtty;
}
char *
PQoptions(const PGconn *conn)
{
if (!conn)
return NULL;
return conn->pgoptions;
}
ConnStatusType
PQstatus(const PGconn *conn)
{
if (!conn)
return CONNECTION_BAD;
return conn->status;
}
PGTransactionStatusType
PQtransactionStatus(const PGconn *conn)
{
if (!conn || conn->status != CONNECTION_OK)
return PQTRANS_UNKNOWN;
if (conn->asyncStatus != PGASYNC_IDLE)
return PQTRANS_ACTIVE;
return conn->xactStatus;
}
const char *
PQparameterStatus(const PGconn *conn, const char *paramName)
{
const pgParameterStatus *pstatus;
if (!conn || !paramName)
return NULL;
for (pstatus = conn->pstatus; pstatus != NULL; pstatus = pstatus->next)
{
if (strcmp(pstatus->name, paramName) == 0)
return pstatus->value;
}
return NULL;
}
int
PQprotocolVersion(const PGconn *conn)
{
if (!conn)
return 0;
if (conn->status == CONNECTION_BAD)
return 0;
return PG_PROTOCOL_MAJOR(conn->pversion);
}
int
PQserverVersion(const PGconn *conn)
{
if (!conn)
return 0;
if (conn->status == CONNECTION_BAD)
return 0;
return conn->sversion;
}
char *
PQerrorMessage(const PGconn *conn)
{
if (!conn)
return libpq_gettext("connection pointer is NULL\n");
return conn->errorMessage.data;
}
/*
* In Windows, socket values are unsigned, and an invalid socket value
* (INVALID_SOCKET) is ~0, which equals -1 in comparisons (with no compiler
* warning). Ideally we would return an unsigned value for PQsocket() on
* Windows, but that would cause the function's return value to differ from
* Unix, so we just return -1 for invalid sockets.
* http://msdn.microsoft.com/en-us/library/windows/desktop/cc507522%28v=vs.85%29.aspx
* http://stackoverflow.com/questions/10817252/why-is-invalid-socket-defined-as-0-in-winsock2-h-c
*/
int
PQsocket(const PGconn *conn)
{
if (!conn)
return -1;
return (conn->sock != PGINVALID_SOCKET) ? conn->sock : -1;
}
int
PQbackendPID(const PGconn *conn)
{
if (!conn || conn->status != CONNECTION_OK)
return 0;
return conn->be_pid;
}
int
PQconnectionNeedsPassword(const PGconn *conn)
{
char *password;
if (!conn)
return false;
password = PQpass(conn);
if (conn->password_needed &&
(password == NULL || password[0] == '\0'))
return true;
else
return false;
}
int
PQconnectionUsedPassword(const PGconn *conn)
{
if (!conn)
return false;
if (conn->password_needed)
return true;
else
return false;
}
int
PQclientEncoding(const PGconn *conn)
{
if (!conn || conn->status != CONNECTION_OK)
return -1;
return conn->client_encoding;
}
int
PQsetClientEncoding(PGconn *conn, const char *encoding)
{
char qbuf[128];
static const char query[] = "set client_encoding to '%s'";
PGresult *res;
int status;
if (!conn || conn->status != CONNECTION_OK)
return -1;
if (!encoding)
return -1;
/* Resolve special "auto" value from the locale */
if (strcmp(encoding, "auto") == 0)
encoding = pg_encoding_to_char(pg_get_encoding_from_locale(NULL, true));
/* check query buffer overflow */
if (sizeof(qbuf) < (sizeof(query) + strlen(encoding)))
return -1;
/* ok, now send a query */
sprintf(qbuf, query, encoding);
res = PQexec(conn, qbuf);
if (res == NULL)
return -1;
if (res->resultStatus != PGRES_COMMAND_OK)
status = -1;
else
{
/*
* In protocol 2 we have to assume the setting will stick, and adjust
* our state immediately. In protocol 3 and up we can rely on the
* backend to report the parameter value, and we'll change state at
* that time.
*/
if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
pqSaveParameterStatus(conn, "client_encoding", encoding);
status = 0; /* everything is ok */
}
PQclear(res);
return status;
}
PGVerbosity
PQsetErrorVerbosity(PGconn *conn, PGVerbosity verbosity)
{
PGVerbosity old;
if (!conn)
return PQERRORS_DEFAULT;
old = conn->verbosity;
conn->verbosity = verbosity;
return old;
}
PGContextVisibility
PQsetErrorContextVisibility(PGconn *conn, PGContextVisibility show_context)
{
PGContextVisibility old;
if (!conn)
return PQSHOW_CONTEXT_ERRORS;
old = conn->show_context;
conn->show_context = show_context;
return old;
}
void
PQtrace(PGconn *conn, FILE *debug_port)
{
if (conn == NULL)
return;
PQuntrace(conn);
conn->Pfdebug = debug_port;
}
void
PQuntrace(PGconn *conn)
{
if (conn == NULL)
return;
if (conn->Pfdebug)
{
fflush(conn->Pfdebug);
conn->Pfdebug = NULL;
}
}
PQnoticeReceiver
PQsetNoticeReceiver(PGconn *conn, PQnoticeReceiver proc, void *arg)
{
PQnoticeReceiver old;
if (conn == NULL)
return NULL;
old = conn->noticeHooks.noticeRec;
if (proc)
{
conn->noticeHooks.noticeRec = proc;
conn->noticeHooks.noticeRecArg = arg;
}
return old;
}
PQnoticeProcessor
PQsetNoticeProcessor(PGconn *conn, PQnoticeProcessor proc, void *arg)
{
PQnoticeProcessor old;
if (conn == NULL)
return NULL;
old = conn->noticeHooks.noticeProc;
if (proc)
{
conn->noticeHooks.noticeProc = proc;
conn->noticeHooks.noticeProcArg = arg;
}
return old;
}
/*
* The default notice message receiver just gets the standard notice text
* and sends it to the notice processor. This two-level setup exists
* mostly for backwards compatibility; perhaps we should deprecate use of
* PQsetNoticeProcessor?
*/
static void
defaultNoticeReceiver(void *arg, const PGresult *res)
{
(void) arg; /* not used */
if (res->noticeHooks.noticeProc != NULL)
res->noticeHooks.noticeProc(res->noticeHooks.noticeProcArg,
PQresultErrorMessage(res));
}
/*
* The default notice message processor just prints the
* message on stderr. Applications can override this if they
* want the messages to go elsewhere (a window, for example).
* Note that simply discarding notices is probably a bad idea.
*/
static void
defaultNoticeProcessor(void *arg, const char *message)
{
(void) arg; /* not used */
/* Note: we expect the supplied string to end with a newline already. */
fprintf(stderr, "%s", message);
}
/*
* returns a pointer to the next token or NULL if the current
* token doesn't match
*/
static char *
pwdfMatchesString(char *buf, const char *token)
{
char *tbuf;
const char *ttok;
bool bslash = false;
if (buf == NULL || token == NULL)
return NULL;
tbuf = buf;
ttok = token;
if (tbuf[0] == '*' && tbuf[1] == ':')
return tbuf + 2;
while (*tbuf != 0)
{
if (*tbuf == '\\' && !bslash)
{
tbuf++;
bslash = true;
}
if (*tbuf == ':' && *ttok == 0 && !bslash)
return tbuf + 1;
bslash = false;
if (*ttok == 0)
return NULL;
if (*tbuf == *ttok)
{
tbuf++;
ttok++;
}
else
return NULL;
}
return NULL;
}
/* Get a password from the password file. Return value is malloc'd. */
static char *
passwordFromFile(const char *hostname, const char *port, const char *dbname,
const char *username, const char *pgpassfile)
{
FILE *fp;
struct stat stat_buf;
#define LINELEN NAMEDATALEN*5
char buf[LINELEN];
if (dbname == NULL || dbname[0] == '\0')
return NULL;
if (username == NULL || username[0] == '\0')
return NULL;
/* 'localhost' matches pghost of '' or the default socket directory */
if (hostname == NULL || hostname[0] == '\0')
hostname = DefaultHost;
else if (is_absolute_path(hostname))
/*
* We should probably use canonicalize_path(), but then we have to
* bring path.c into libpq, and it doesn't seem worth it.
*/
if (strcmp(hostname, DEFAULT_PGSOCKET_DIR) == 0)
hostname = DefaultHost;
if (port == NULL || port[0] == '\0')
port = DEF_PGPORT_STR;
/* If password file cannot be opened, ignore it. */
if (stat(pgpassfile, &stat_buf) != 0)
return NULL;
#ifndef WIN32
if (!S_ISREG(stat_buf.st_mode))
{
fprintf(stderr,
libpq_gettext("WARNING: password file \"%s\" is not a plain file\n"),
pgpassfile);
return NULL;
}
/* If password file is insecure, alert the user and ignore it. */
if (stat_buf.st_mode & (S_IRWXG | S_IRWXO))
{
fprintf(stderr,
libpq_gettext("WARNING: password file \"%s\" has group or world access; permissions should be u=rw (0600) or less\n"),
pgpassfile);
return NULL;
}
#else
/*
* On Win32, the directory is protected, so we don't have to check the
* file.
*/
#endif
fp = fopen(pgpassfile, "r");
if (fp == NULL)
return NULL;
while (!feof(fp) && !ferror(fp))
{
char *t = buf,
*ret,
*p1,
*p2;
int len;
if (fgets(buf, sizeof(buf), fp) == NULL)
break;
/* strip trailing newline and carriage return */
len = pg_strip_crlf(buf);
if (len == 0)
continue;
if ((t = pwdfMatchesString(t, hostname)) == NULL ||
(t = pwdfMatchesString(t, port)) == NULL ||
(t = pwdfMatchesString(t, dbname)) == NULL ||
(t = pwdfMatchesString(t, username)) == NULL)
continue;
/* Found a match. */
ret = strdup(t);
fclose(fp);
if (!ret)
{
/* Out of memory. XXX: an error message would be nice. */
explicit_bzero(buf, sizeof(buf));
return NULL;
}
/* De-escape password. */
for (p1 = p2 = ret; *p1 != ':' && *p1 != '\0'; ++p1, ++p2)
{
if (*p1 == '\\' && p1[1] != '\0')
++p1;
*p2 = *p1;
}
*p2 = '\0';
return ret;
}
fclose(fp);
explicit_bzero(buf, sizeof(buf));
return NULL;
#undef LINELEN
}
/*
* If the connection failed due to bad password, we should mention
* if we got the password from the pgpassfile.
*/
static void
pgpassfileWarning(PGconn *conn)
{
/* If it was 'invalid authorization', add pgpassfile mention */
/* only works with >= 9.0 servers */
if (conn->password_needed &&
conn->connhost[conn->whichhost].password != NULL &&
conn->result)
{
const char *sqlstate = PQresultErrorField(conn->result,
PG_DIAG_SQLSTATE);
if (sqlstate && strcmp(sqlstate, ERRCODE_INVALID_PASSWORD) == 0)
appendPQExpBuffer(&conn->errorMessage,
libpq_gettext("password retrieved from file \"%s\"\n"),
conn->pgpassfile);
}
}
/*
* Check if the SSL procotol value given in input is valid or not.
* This is used as a sanity check routine for the connection parameters
* sslminprotocolversion and sslmaxprotocolversion.
*/
static bool
sslVerifyProtocolVersion(const char *version)
{
/*
* An empty string and a NULL value are considered valid as it is
* equivalent to ignoring the parameter.
*/
if (!version || strlen(version) == 0)
return true;
if (pg_strcasecmp(version, "TLSv1") == 0 ||
pg_strcasecmp(version, "TLSv1.1") == 0 ||
pg_strcasecmp(version, "TLSv1.2") == 0 ||
pg_strcasecmp(version, "TLSv1.3") == 0)
return true;
/* anything else is wrong */
return false;
}
/*
* Ensure that the SSL protocol range given in input is correct. The check
* is performed on the input string to keep it TLS backend agnostic. Input
* to this function is expected verified with sslVerifyProtocolVersion().
*/
static bool
sslVerifyProtocolRange(const char *min, const char *max)
{
Assert(sslVerifyProtocolVersion(min) &&
sslVerifyProtocolVersion(max));
/* If at least one of the bounds is not set, the range is valid */
if (min == NULL || max == NULL || strlen(min) == 0 || strlen(max) == 0)
return true;
/*
* If the minimum version is the lowest one we accept, then all options
* for the maximum are valid.
*/
if (pg_strcasecmp(min, "TLSv1") == 0)
return true;
/*
* The minimum bound is valid, and cannot be TLSv1, so using TLSv1 for the
* maximum is incorrect.
*/
if (pg_strcasecmp(max, "TLSv1") == 0)
return false;
/*
* At this point we know that we have a mix of TLSv1.1 through 1.3
* versions.
*/
if (pg_strcasecmp(min, max) > 0)
return false;
return true;
}
/*
* Obtain user's home directory, return in given buffer
*
* On Unix, this actually returns the user's home directory. On Windows
* it returns the PostgreSQL-specific application data folder.
*
* This is essentially the same as get_home_path(), but we don't use that
* because we don't want to pull path.c into libpq (it pollutes application
* namespace).
*
* Returns true on success, false on failure to obtain the directory name.
*
* CAUTION: although in most situations failure is unexpected, there are users
* who like to run applications in a home-directory-less environment. On
* failure, you almost certainly DO NOT want to report an error. Just act as
* though whatever file you were hoping to find in the home directory isn't
* there (which it isn't).
*/
bool
pqGetHomeDirectory(char *buf, int bufsize)
{
#ifndef WIN32
char pwdbuf[BUFSIZ];
struct passwd pwdstr;
struct passwd *pwd = NULL;
(void) pqGetpwuid(geteuid(), &pwdstr, pwdbuf, sizeof(pwdbuf), &pwd);
if (pwd == NULL)
return false;
strlcpy(buf, pwd->pw_dir, bufsize);
return true;
#else
char tmppath[MAX_PATH];
ZeroMemory(tmppath, sizeof(tmppath));
if (SHGetFolderPath(NULL, CSIDL_APPDATA, NULL, 0, tmppath) != S_OK)
return false;
snprintf(buf, bufsize, "%s/postgresql", tmppath);
return true;
#endif
}
/*
* To keep the API consistent, the locking stubs are always provided, even
* if they are not required.
*/
static void
default_threadlock(int acquire)
{
#ifdef ENABLE_THREAD_SAFETY
#ifndef WIN32
static pthread_mutex_t singlethread_lock = PTHREAD_MUTEX_INITIALIZER;
#else
static pthread_mutex_t singlethread_lock = NULL;
static long mutex_initlock = 0;
if (singlethread_lock == NULL)
{
while (InterlockedExchange(&mutex_initlock, 1) == 1)
/* loop, another thread own the lock */ ;
if (singlethread_lock == NULL)
{
if (pthread_mutex_init(&singlethread_lock, NULL))
PGTHREAD_ERROR("failed to initialize mutex");
}
InterlockedExchange(&mutex_initlock, 0);
}
#endif
if (acquire)
{
if (pthread_mutex_lock(&singlethread_lock))
PGTHREAD_ERROR("failed to lock mutex");
}
else
{
if (pthread_mutex_unlock(&singlethread_lock))
PGTHREAD_ERROR("failed to unlock mutex");
}
#endif
}
pgthreadlock_t
PQregisterThreadLock(pgthreadlock_t newhandler)
{
pgthreadlock_t prev = pg_g_threadlock;
if (newhandler)
pg_g_threadlock = newhandler;
else
pg_g_threadlock = default_threadlock;
return prev;
}