From b2a3d706b8d76b9d65e953942fc1ccafe892f692 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Thu, 1 Aug 2019 09:37:28 +0900 Subject: [PATCH] Fix handling of previous password hooks in passwordcheck When piling up loading of modules using check_password_hook_type, loading passwordcheck would remove any trace of a previously-loaded hook. Unloading the module would also cause previous hooks to be entirely gone. Reported-by: Rafael Castro Author: Michael Paquier Reviewed-by: Daniel Gustafsson Discussion: https://postgr.es/m/15932-78f48f9ef166778c@postgresql.org Backpatch-through: 9.4 --- contrib/passwordcheck/passwordcheck.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/contrib/passwordcheck/passwordcheck.c b/contrib/passwordcheck/passwordcheck.c index b161e0f146..c3fb5a9c08 100644 --- a/contrib/passwordcheck/passwordcheck.c +++ b/contrib/passwordcheck/passwordcheck.c @@ -26,10 +26,14 @@ PG_MODULE_MAGIC; +/* Saved hook value in case of unload */ +static check_password_hook_type prev_check_password_hook = NULL; + /* passwords shorter than this will be rejected */ #define MIN_PWD_LENGTH 8 extern void _PG_init(void); +extern void _PG_fini(void); /* * check_password @@ -55,6 +59,11 @@ check_password(const char *username, Datum validuntil_time, bool validuntil_null) { + if (prev_check_password_hook) + prev_check_password_hook(username, shadow_pass, + password_type, validuntil_time, + validuntil_null); + if (password_type != PASSWORD_TYPE_PLAINTEXT) { /* @@ -133,5 +142,16 @@ void _PG_init(void) { /* activate password checks when the module is loaded */ + prev_check_password_hook = check_password_hook; check_password_hook = check_password; } + +/* + * Module unload function + */ +void +_PG_fini(void) +{ + /* uninstall hook */ + check_password_hook = prev_check_password_hook; +}