mirror of https://git.zx2c4.com/WireGuard
566 lines
21 KiB
C
566 lines
21 KiB
C
/* Copyright 2015-2016 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
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#include "wireguard.h"
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#include "noise.h"
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#include "messages.h"
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#include "packets.h"
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#include "hashtables.h"
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#include <crypto/algapi.h>
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#include <linux/rcupdate.h>
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#include <linux/slab.h>
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#include <linux/bitmap.h>
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#include <linux/scatterlist.h>
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#include <linux/highmem.h>
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/* This implements Noise_IK:
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*
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* <- s
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* ******
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* -> e, dhes, s, dhss, t
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* <- e, dhee, dhes
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*/
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static const u8 handshake_name[33] = "Noise_IK_25519_ChaChaPoly_BLAKE2s";
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static const u8 handshake_psk_name[36] = "NoisePSK_IK_25519_ChaChaPoly_BLAKE2s";
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static u8 handshake_name_hash[NOISE_HASH_LEN];
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static u8 handshake_psk_name_hash[NOISE_HASH_LEN];
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static const u8 identifier_name[34] = "WireGuard v0 zx2c4 Jason@zx2c4.com";
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static atomic64_t keypair_counter = ATOMIC64_INIT(0);
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void noise_init(void)
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{
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blake2s(handshake_name_hash, handshake_name, NULL, NOISE_HASH_LEN, sizeof(handshake_name), 0);
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blake2s(handshake_psk_name_hash, handshake_psk_name, NULL, NOISE_HASH_LEN, sizeof(handshake_psk_name), 0);
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}
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void noise_handshake_init(struct noise_handshake *handshake, struct noise_static_identity *static_identity, const u8 peer_public_key[NOISE_PUBLIC_KEY_LEN], struct wireguard_peer *peer)
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{
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memset(handshake, 0, sizeof(struct noise_handshake));
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init_rwsem(&handshake->lock);
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handshake->entry.type = INDEX_HASHTABLE_HANDSHAKE;
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handshake->entry.peer = peer;
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memcpy(handshake->remote_static, peer_public_key, NOISE_PUBLIC_KEY_LEN);
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handshake->static_identity = static_identity;
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handshake->state = HANDSHAKE_ZEROED;
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}
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void noise_handshake_clear(struct noise_handshake *handshake)
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{
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index_hashtable_remove(&handshake->entry.peer->device->index_hashtable, &handshake->entry);
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down_write(&handshake->lock);
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memset(&handshake->ephemeral_public, 0, NOISE_PUBLIC_KEY_LEN);
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memset(&handshake->ephemeral_private, 0, NOISE_PUBLIC_KEY_LEN);
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memset(&handshake->remote_ephemeral, 0, NOISE_PUBLIC_KEY_LEN);
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memset(&handshake->hash, 0, NOISE_HASH_LEN);
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memset(&handshake->chaining_key, 0, NOISE_HASH_LEN);
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memset(&handshake->key, 0, NOISE_SYMMETRIC_KEY_LEN);
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handshake->remote_index = 0;
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handshake->state = HANDSHAKE_ZEROED;
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up_write(&handshake->lock);
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index_hashtable_remove(&handshake->entry.peer->device->index_hashtable, &handshake->entry);
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}
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static struct noise_keypair *keypair_create(struct wireguard_peer *peer)
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{
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struct noise_keypair *keypair = kzalloc(sizeof(struct noise_keypair), GFP_KERNEL);
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if (unlikely(!keypair))
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return NULL;
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keypair->internal_id = atomic64_inc_return(&keypair_counter);
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keypair->entry.type = INDEX_HASHTABLE_KEYPAIR;
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keypair->entry.peer = peer;
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kref_init(&keypair->refcount);
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return keypair;
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}
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static void keypair_free_rcu(struct rcu_head *rcu)
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{
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struct noise_keypair *keypair = container_of(rcu, struct noise_keypair, rcu);
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net_dbg_ratelimited("Keypair %Lu destroyed for peer %Lu\n", keypair->internal_id, keypair->entry.peer->internal_id);
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kzfree(keypair);
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}
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static void keypair_free_kref(struct kref *kref)
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{
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struct noise_keypair *keypair = container_of(kref, struct noise_keypair, refcount);
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index_hashtable_remove(&keypair->entry.peer->device->index_hashtable, &keypair->entry);
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call_rcu(&keypair->rcu, keypair_free_rcu);
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}
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void noise_keypair_put(struct noise_keypair *keypair)
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{
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if (unlikely(!keypair))
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return;
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kref_put(&keypair->refcount, keypair_free_kref);
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}
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void noise_keypairs_clear(struct noise_keypairs *keypairs)
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{
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struct noise_keypair *old;
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mutex_lock(&keypairs->keypair_update_lock);
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old = rcu_dereference_protected(keypairs->previous_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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rcu_assign_pointer(keypairs->previous_keypair, NULL);
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noise_keypair_put(old);
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old = rcu_dereference_protected(keypairs->next_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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rcu_assign_pointer(keypairs->next_keypair, NULL);
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noise_keypair_put(old);
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old = rcu_dereference_protected(keypairs->current_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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rcu_assign_pointer(keypairs->current_keypair, NULL);
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noise_keypair_put(old);
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mutex_unlock(&keypairs->keypair_update_lock);
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}
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static void add_new_keypair(struct noise_keypairs *keypairs, struct noise_keypair *new_keypair)
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{
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struct noise_keypair *previous_keypair, *next_keypair, *current_keypair;
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mutex_lock(&keypairs->keypair_update_lock);
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previous_keypair = rcu_dereference_protected(keypairs->previous_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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next_keypair = rcu_dereference_protected(keypairs->next_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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current_keypair = rcu_dereference_protected(keypairs->current_keypair, lockdep_is_held(&keypairs->keypair_update_lock));
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if (new_keypair->i_am_the_initiator) {
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if (next_keypair) {
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rcu_assign_pointer(keypairs->next_keypair, NULL);
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rcu_assign_pointer(keypairs->previous_keypair, next_keypair);
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noise_keypair_put(current_keypair);
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} else
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rcu_assign_pointer(keypairs->previous_keypair, current_keypair);
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noise_keypair_put(previous_keypair);
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rcu_assign_pointer(keypairs->current_keypair, new_keypair);
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} else {
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rcu_assign_pointer(keypairs->next_keypair, new_keypair);
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noise_keypair_put(next_keypair);
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rcu_assign_pointer(keypairs->previous_keypair, NULL);
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noise_keypair_put(previous_keypair);
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}
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mutex_unlock(&keypairs->keypair_update_lock);
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}
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bool noise_received_with_keypair(struct noise_keypairs *keypairs, struct noise_keypair *received_keypair)
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{
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bool ret = false;
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struct noise_keypair *old_keypair;
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/* TODO: probably this needs the actual mutex, but we're in atomic context,
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* so we can't take it here. Instead we just rely on RCU for the lookups. */
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rcu_read_lock();
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if (unlikely(received_keypair == rcu_dereference(keypairs->next_keypair))) {
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ret = true;
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old_keypair = rcu_dereference(keypairs->previous_keypair);
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rcu_assign_pointer(keypairs->previous_keypair, rcu_dereference(keypairs->current_keypair));
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noise_keypair_put(old_keypair);
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rcu_assign_pointer(keypairs->current_keypair, received_keypair);
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rcu_assign_pointer(keypairs->next_keypair, NULL);
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}
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rcu_read_unlock();
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return ret;
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}
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void noise_set_static_identity_private_key(struct noise_static_identity *static_identity, const u8 private_key[NOISE_PUBLIC_KEY_LEN])
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{
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down_write(&static_identity->lock);
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if (private_key) {
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memcpy(static_identity->static_private, private_key, NOISE_PUBLIC_KEY_LEN);
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curve25519_generate_public(static_identity->static_public, private_key);
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static_identity->has_identity = true;
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} else {
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memset(static_identity->static_private, 0, NOISE_PUBLIC_KEY_LEN);
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memset(static_identity->static_public, 0, NOISE_PUBLIC_KEY_LEN);
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static_identity->has_identity = false;
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}
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up_write(&static_identity->lock);
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}
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void noise_set_static_identity_preshared_key(struct noise_static_identity *static_identity, const u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN])
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{
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down_write(&static_identity->lock);
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if (preshared_key) {
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memcpy(static_identity->preshared_key, preshared_key, NOISE_SYMMETRIC_KEY_LEN);
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static_identity->has_psk = true;
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} else {
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memset(static_identity->preshared_key, 0, NOISE_SYMMETRIC_KEY_LEN);
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static_identity->has_psk = false;
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}
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up_write(&static_identity->lock);
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}
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/* This is Hugo Krawczyk's HKDF:
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* - https://eprint.iacr.org/2010/264.pdf
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* - https://tools.ietf.org/html/rfc5869
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*/
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static void kdf(u8 *first_dst, u8 *second_dst, const u8 *data,
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size_t first_len, size_t second_len, size_t data_len,
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const u8 chaining_key[NOISE_HASH_LEN])
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{
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u8 secret[BLAKE2S_OUTBYTES];
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u8 output[BLAKE2S_OUTBYTES + 1];
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BUG_ON(first_len > BLAKE2S_OUTBYTES || second_len > BLAKE2S_OUTBYTES);
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/* Extract entropy from data into secret */
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blake2s_hmac(secret, data, chaining_key, BLAKE2S_OUTBYTES, data_len, NOISE_HASH_LEN);
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/* Expand first key: key = secret, data = 0x1 */
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output[0] = 1;
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blake2s_hmac(output, output, secret, BLAKE2S_OUTBYTES, 1, BLAKE2S_OUTBYTES);
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memcpy(first_dst, output, first_len);
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/* Expand second key: key = secret, data = first-key || 0x2 */
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output[BLAKE2S_OUTBYTES] = 2;
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blake2s_hmac(output, output, secret, BLAKE2S_OUTBYTES, BLAKE2S_OUTBYTES + 1, BLAKE2S_OUTBYTES);
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memcpy(second_dst, output, second_len);
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/* Clear sensitive data from stack */
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memzero_explicit(secret, BLAKE2S_OUTBYTES);
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memzero_explicit(output, BLAKE2S_OUTBYTES + 1);
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}
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static void symmetric_key_init(struct noise_symmetric_key *key)
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{
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spin_lock_init(&key->counter.receive.lock);
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atomic64_set(&key->counter.counter, 0);
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key->counter.receive.backtrack = 0;
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key->birthdate = get_jiffies_64();
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key->is_valid = true;
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}
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static void derive_keys(struct noise_symmetric_key *first_dst, struct noise_symmetric_key *second_dst, const u8 chaining_key[NOISE_HASH_LEN])
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{
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kdf(first_dst->key, second_dst->key, NULL, NOISE_SYMMETRIC_KEY_LEN, NOISE_SYMMETRIC_KEY_LEN, 0, chaining_key);
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symmetric_key_init(first_dst);
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symmetric_key_init(second_dst);
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}
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static void mix_key(u8 key[NOISE_SYMMETRIC_KEY_LEN], u8 chaining_key[NOISE_HASH_LEN], const u8 *src, size_t src_len)
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{
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kdf(chaining_key, key, src, NOISE_HASH_LEN, NOISE_SYMMETRIC_KEY_LEN, src_len, chaining_key);
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}
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static void mix_dh(u8 key[NOISE_SYMMETRIC_KEY_LEN], u8 chaining_key[NOISE_HASH_LEN],
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const u8 private[NOISE_PUBLIC_KEY_LEN], const u8 public[NOISE_PUBLIC_KEY_LEN])
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{
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u8 dh_calculation[NOISE_PUBLIC_KEY_LEN];
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curve25519(dh_calculation, private, public);
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mix_key(key, chaining_key, dh_calculation, NOISE_PUBLIC_KEY_LEN);
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memzero_explicit(dh_calculation, NOISE_PUBLIC_KEY_LEN);
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}
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static void mix_hash(u8 hash[NOISE_HASH_LEN], const u8 *src, size_t src_len)
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{
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struct blake2s_state blake;
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blake2s_init(&blake, NOISE_HASH_LEN);
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blake2s_update(&blake, hash, NOISE_HASH_LEN);
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blake2s_update(&blake, src, src_len);
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blake2s_final(&blake, hash, NOISE_HASH_LEN);
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}
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static void handshake_init(u8 key[NOISE_SYMMETRIC_KEY_LEN], u8 chaining_key[NOISE_HASH_LEN], u8 hash[NOISE_HASH_LEN],
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const u8 remote_static[NOISE_PUBLIC_KEY_LEN], const u8 psk[NOISE_SYMMETRIC_KEY_LEN])
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{
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memset(key, 0, NOISE_SYMMETRIC_KEY_LEN);
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memcpy(hash, psk ? handshake_psk_name_hash : handshake_name_hash, NOISE_HASH_LEN);
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mix_hash(hash, identifier_name, sizeof(identifier_name));
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if (psk) {
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u8 temp_hash[NOISE_HASH_LEN];
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kdf(chaining_key, temp_hash, psk, NOISE_HASH_LEN, NOISE_HASH_LEN, NOISE_SYMMETRIC_KEY_LEN, handshake_psk_name_hash);
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mix_hash(hash, temp_hash, NOISE_HASH_LEN);
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memzero_explicit(temp_hash, NOISE_HASH_LEN);
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} else
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memcpy(chaining_key, handshake_name_hash, NOISE_HASH_LEN);
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mix_hash(hash, remote_static, NOISE_PUBLIC_KEY_LEN);
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}
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static bool handshake_encrypt(u8 *dst_ciphertext, const u8 *src_plaintext, size_t src_len, u8 key[NOISE_SYMMETRIC_KEY_LEN], u8 hash[NOISE_HASH_LEN])
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{
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if (!chacha20poly1305_encrypt(dst_ciphertext, src_plaintext, src_len, hash, NOISE_HASH_LEN, 0 /* Always zero for Noise_IK */, key))
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return false;
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mix_hash(hash, dst_ciphertext, noise_encrypted_len(src_len));
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return true;
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}
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static bool handshake_decrypt(u8 *dst_plaintext, const u8 *src_ciphertext, size_t src_len, u8 key[NOISE_SYMMETRIC_KEY_LEN], u8 hash[NOISE_HASH_LEN])
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{
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if (!chacha20poly1305_decrypt(dst_plaintext, src_ciphertext, src_len, hash, NOISE_HASH_LEN, 0 /* Always zero for Noise_IK */, key))
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return false;
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mix_hash(hash, src_ciphertext, src_len);
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return true;
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}
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static void handshake_nocrypt(u8 *dst, const u8 *src, size_t src_len, u8 hash[NOISE_HASH_LEN])
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{
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memcpy(dst, src, src_len);
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mix_hash(hash, src, src_len);
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}
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static void tai64n_now(u8 output[NOISE_TIMESTAMP_LEN])
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{
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struct timeval now;
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do_gettimeofday(&now);
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/* http://cr.yp.to/libtai/tai64.html */
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*(__be64 *)output = cpu_to_be64(now.tv_sec);
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*(__be32 *)(output + sizeof(__be64)) = cpu_to_be32(1000 * now.tv_usec + 500);
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}
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bool noise_handshake_create_initiation(struct message_handshake_initiation *dst, struct noise_handshake *handshake)
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{
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u8 timestamp[NOISE_TIMESTAMP_LEN];
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bool ret = false;
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down_read(&handshake->static_identity->lock);
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down_write(&handshake->lock);
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if (unlikely(!handshake->static_identity->has_identity))
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goto out;
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dst->header.type = MESSAGE_HANDSHAKE_INITIATION;
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handshake_init(handshake->key, handshake->chaining_key, handshake->hash, handshake->remote_static,
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handshake->static_identity->has_psk ? handshake->static_identity->preshared_key : NULL);
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/* e */
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curve25519_generate_secret(handshake->ephemeral_private);
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curve25519_generate_public(handshake->ephemeral_public, handshake->ephemeral_private);
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handshake_nocrypt(dst->unencrypted_ephemeral, handshake->ephemeral_public, NOISE_PUBLIC_KEY_LEN, handshake->hash);
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if (handshake->static_identity->has_psk)
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mix_key(handshake->key, handshake->chaining_key, handshake->ephemeral_public, NOISE_PUBLIC_KEY_LEN);
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/* dhes */
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mix_dh(handshake->key, handshake->chaining_key, handshake->ephemeral_private, handshake->remote_static);
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/* s */
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if (!handshake_encrypt(dst->encrypted_static, handshake->static_identity->static_public, NOISE_PUBLIC_KEY_LEN, handshake->key, handshake->hash))
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goto out;
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/* dhss */
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mix_dh(handshake->key, handshake->chaining_key, handshake->static_identity->static_private, handshake->remote_static);
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/* t */
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tai64n_now(timestamp);
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if (!handshake_encrypt(dst->encrypted_timestamp, timestamp, NOISE_TIMESTAMP_LEN, handshake->key, handshake->hash))
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goto out;
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dst->sender_index = index_hashtable_insert(&handshake->entry.peer->device->index_hashtable, &handshake->entry);
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ret = true;
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handshake->state = HANDSHAKE_CREATED_INITIATION;
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out:
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up_write(&handshake->lock);
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up_read(&handshake->static_identity->lock);
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return ret;
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}
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struct wireguard_peer *noise_handshake_consume_initiation(struct message_handshake_initiation *src, struct wireguard_device *wg)
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{
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bool replay_attack, flood_attack;
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u8 s[NOISE_PUBLIC_KEY_LEN];
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u8 e[NOISE_PUBLIC_KEY_LEN];
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u8 t[NOISE_TIMESTAMP_LEN];
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struct noise_handshake *handshake;
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struct wireguard_peer *wg_peer = NULL;
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u8 key[NOISE_SYMMETRIC_KEY_LEN];
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u8 hash[NOISE_HASH_LEN];
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u8 chaining_key[NOISE_HASH_LEN];
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down_read(&wg->static_identity.lock);
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if (unlikely(!wg->static_identity.has_identity))
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goto out;
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handshake_init(key, chaining_key, hash, wg->static_identity.static_public,
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wg->static_identity.has_psk ? wg->static_identity.preshared_key : NULL);
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/* e */
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handshake_nocrypt(e, src->unencrypted_ephemeral, sizeof(src->unencrypted_ephemeral), hash);
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if (wg->static_identity.has_psk)
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mix_key(key, chaining_key, e, NOISE_PUBLIC_KEY_LEN);
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/* dhes */
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mix_dh(key, chaining_key, wg->static_identity.static_private, e);
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/* s */
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if (!handshake_decrypt(s, src->encrypted_static, sizeof(src->encrypted_static), key, hash))
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goto out;
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/* dhss */
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mix_dh(key, chaining_key, wg->static_identity.static_private, s);
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/* t */
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if (!handshake_decrypt(t, src->encrypted_timestamp, sizeof(src->encrypted_timestamp), key, hash))
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goto out;
|
|
|
|
/* Lookup which peer we're actually talking to */
|
|
wg_peer = pubkey_hashtable_lookup(&wg->peer_hashtable, s);
|
|
if (!wg_peer)
|
|
goto out;
|
|
handshake = &wg_peer->handshake;
|
|
down_read(&handshake->lock);
|
|
replay_attack = memcmp(t, handshake->latest_timestamp, NOISE_TIMESTAMP_LEN) <= 0;
|
|
flood_attack = !time_is_before_jiffies64(handshake->last_initiation_consumption + INITIATIONS_PER_SECOND);
|
|
up_read(&handshake->lock);
|
|
if (replay_attack || flood_attack) {
|
|
peer_put(wg_peer);
|
|
wg_peer = NULL;
|
|
goto out;
|
|
}
|
|
|
|
/* Success! Copy everything to peer */
|
|
down_write(&handshake->lock);
|
|
memcpy(handshake->remote_ephemeral, e, NOISE_PUBLIC_KEY_LEN);
|
|
memcpy(handshake->latest_timestamp, t, NOISE_TIMESTAMP_LEN);
|
|
memcpy(handshake->key, key, NOISE_SYMMETRIC_KEY_LEN);
|
|
memcpy(handshake->hash, hash, NOISE_HASH_LEN);
|
|
memcpy(handshake->chaining_key, chaining_key, NOISE_HASH_LEN);
|
|
handshake->remote_index = src->sender_index;
|
|
handshake->last_initiation_consumption = get_jiffies_64();
|
|
handshake->state = HANDSHAKE_CONSUMED_INITIATION;
|
|
up_write(&handshake->lock);
|
|
|
|
out:
|
|
memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
|
|
memzero_explicit(hash, NOISE_HASH_LEN);
|
|
memzero_explicit(chaining_key, NOISE_HASH_LEN);
|
|
up_read(&wg->static_identity.lock);
|
|
return wg_peer;
|
|
}
|
|
|
|
bool noise_handshake_create_response(struct message_handshake_response *dst, struct noise_handshake *handshake)
|
|
{
|
|
bool ret = false;
|
|
down_read(&handshake->static_identity->lock);
|
|
down_write(&handshake->lock);
|
|
|
|
if (handshake->state != HANDSHAKE_CONSUMED_INITIATION)
|
|
goto out;
|
|
|
|
dst->header.type = MESSAGE_HANDSHAKE_RESPONSE;
|
|
dst->receiver_index = handshake->remote_index;
|
|
|
|
/* e */
|
|
curve25519_generate_secret(handshake->ephemeral_private);
|
|
curve25519_generate_public(handshake->ephemeral_public, handshake->ephemeral_private);
|
|
handshake_nocrypt(dst->unencrypted_ephemeral, handshake->ephemeral_public, NOISE_PUBLIC_KEY_LEN, handshake->hash);
|
|
if (handshake->static_identity->has_psk)
|
|
mix_key(handshake->key, handshake->chaining_key, handshake->ephemeral_public, NOISE_PUBLIC_KEY_LEN);
|
|
|
|
/* dhee */
|
|
mix_dh(handshake->key, handshake->chaining_key, handshake->ephemeral_private, handshake->remote_ephemeral);
|
|
|
|
/* dhes */
|
|
mix_dh(handshake->key, handshake->chaining_key, handshake->ephemeral_private, handshake->remote_static);
|
|
|
|
if (!handshake_encrypt(dst->encrypted_nothing, NULL, 0, handshake->key, handshake->hash))
|
|
goto out;
|
|
|
|
dst->sender_index = index_hashtable_insert(&handshake->entry.peer->device->index_hashtable, &handshake->entry);
|
|
|
|
handshake->state = HANDSHAKE_CREATED_RESPONSE;
|
|
ret = true;
|
|
|
|
out:
|
|
up_write(&handshake->lock);
|
|
up_read(&handshake->static_identity->lock);
|
|
return ret;
|
|
}
|
|
|
|
struct wireguard_peer *noise_handshake_consume_response(struct message_handshake_response *src, struct wireguard_device *wg)
|
|
{
|
|
struct noise_handshake *handshake;
|
|
struct wireguard_peer *ret_peer = NULL;
|
|
u8 key[NOISE_SYMMETRIC_KEY_LEN];
|
|
u8 hash[NOISE_HASH_LEN];
|
|
u8 chaining_key[NOISE_HASH_LEN];
|
|
u8 e[NOISE_PUBLIC_KEY_LEN];
|
|
u8 ephemeral_private[NOISE_PUBLIC_KEY_LEN];
|
|
u8 static_private[NOISE_PUBLIC_KEY_LEN];
|
|
enum noise_handshake_state state = HANDSHAKE_ZEROED;
|
|
|
|
down_read(&wg->static_identity.lock);
|
|
|
|
if (unlikely(!wg->static_identity.has_identity))
|
|
goto out;
|
|
|
|
handshake = (struct noise_handshake *)index_hashtable_lookup(&wg->index_hashtable, INDEX_HASHTABLE_HANDSHAKE, src->receiver_index);
|
|
if (unlikely(!handshake))
|
|
goto out;
|
|
|
|
down_read(&handshake->lock);
|
|
state = handshake->state;
|
|
memcpy(key, handshake->key, NOISE_SYMMETRIC_KEY_LEN);
|
|
memcpy(hash, handshake->hash, NOISE_HASH_LEN);
|
|
memcpy(chaining_key, handshake->chaining_key, NOISE_HASH_LEN);
|
|
memcpy(ephemeral_private, handshake->ephemeral_private, NOISE_PUBLIC_KEY_LEN);
|
|
up_read(&handshake->lock);
|
|
|
|
if (state != HANDSHAKE_CREATED_INITIATION)
|
|
goto fail;
|
|
|
|
/* e */
|
|
handshake_nocrypt(e, src->unencrypted_ephemeral, sizeof(src->unencrypted_ephemeral), hash);
|
|
if (wg->static_identity.has_psk)
|
|
mix_key(key, chaining_key, e, NOISE_PUBLIC_KEY_LEN);
|
|
|
|
/* dhee */
|
|
mix_dh(key, chaining_key, ephemeral_private, e);
|
|
|
|
/* dhes */
|
|
mix_dh(key, chaining_key, wg->static_identity.static_private, e);
|
|
|
|
/* decrypt nothing */
|
|
if (!handshake_decrypt(NULL, src->encrypted_nothing, sizeof(src->encrypted_nothing), key, hash))
|
|
goto fail;
|
|
|
|
/* Success! Copy everything to peer */
|
|
down_write(&handshake->lock);
|
|
memcpy(handshake->remote_ephemeral, e, NOISE_PUBLIC_KEY_LEN);
|
|
memcpy(handshake->key, key, NOISE_SYMMETRIC_KEY_LEN);
|
|
memcpy(handshake->hash, hash, NOISE_HASH_LEN);
|
|
memcpy(handshake->chaining_key, chaining_key, NOISE_HASH_LEN);
|
|
handshake->remote_index = src->sender_index;
|
|
handshake->state = HANDSHAKE_CONSUMED_RESPONSE;
|
|
up_write(&handshake->lock);
|
|
ret_peer = handshake->entry.peer;
|
|
goto out;
|
|
|
|
fail:
|
|
peer_put(handshake->entry.peer);
|
|
out:
|
|
memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
|
|
memzero_explicit(hash, NOISE_HASH_LEN);
|
|
memzero_explicit(chaining_key, NOISE_HASH_LEN);
|
|
memzero_explicit(ephemeral_private, NOISE_PUBLIC_KEY_LEN);
|
|
memzero_explicit(static_private, NOISE_PUBLIC_KEY_LEN);
|
|
up_read(&wg->static_identity.lock);
|
|
return ret_peer;
|
|
}
|
|
|
|
bool noise_handshake_begin_session(struct noise_handshake *handshake, struct noise_keypairs *keypairs, bool i_am_the_initiator)
|
|
{
|
|
struct noise_keypair *new_keypair;
|
|
|
|
down_read(&handshake->lock);
|
|
if (handshake->state != HANDSHAKE_CREATED_RESPONSE && handshake->state != HANDSHAKE_CONSUMED_RESPONSE)
|
|
goto fail;
|
|
|
|
new_keypair = keypair_create(handshake->entry.peer);
|
|
if (!new_keypair)
|
|
goto fail;
|
|
new_keypair->i_am_the_initiator = i_am_the_initiator;
|
|
new_keypair->remote_index = handshake->remote_index;
|
|
|
|
if (i_am_the_initiator)
|
|
derive_keys(&new_keypair->sending, &new_keypair->receiving, handshake->chaining_key);
|
|
else
|
|
derive_keys(&new_keypair->receiving, &new_keypair->sending, handshake->chaining_key);
|
|
up_read(&handshake->lock);
|
|
|
|
add_new_keypair(keypairs, new_keypair);
|
|
index_hashtable_replace(&handshake->entry.peer->device->index_hashtable, &handshake->entry, &new_keypair->entry);
|
|
noise_handshake_clear(handshake);
|
|
net_dbg_ratelimited("Keypair %Lu created for peer %Lu\n", new_keypair->internal_id, new_keypair->entry.peer->internal_id);
|
|
|
|
return true;
|
|
|
|
fail:
|
|
up_read(&handshake->lock);
|
|
return false;
|
|
}
|