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-rw-r--r--src/data.c430
1 files changed, 0 insertions, 430 deletions
diff --git a/src/data.c b/src/data.c
deleted file mode 100644
index fb91861..0000000
--- a/src/data.c
+++ /dev/null
@@ -1,430 +0,0 @@
-/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
-
-#include "noise.h"
-#include "device.h"
-#include "peer.h"
-#include "messages.h"
-#include "packets.h"
-#include "hashtables.h"
-
-#include <linux/rcupdate.h>
-#include <linux/slab.h>
-#include <linux/bitmap.h>
-#include <linux/scatterlist.h>
-#include <net/ip_tunnels.h>
-#include <net/xfrm.h>
-#include <crypto/algapi.h>
-
-struct encryption_ctx {
- struct padata_priv padata;
- struct sk_buff_head queue;
- struct wireguard_peer *peer;
- struct noise_keypair *keypair;
-};
-
-struct decryption_ctx {
- struct padata_priv padata;
- struct endpoint endpoint;
- struct sk_buff *skb;
- struct noise_keypair *keypair;
-};
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
-static struct kmem_cache *encryption_ctx_cache __read_mostly;
-static struct kmem_cache *decryption_ctx_cache __read_mostly;
-
-int __init packet_init_data_caches(void)
-{
- encryption_ctx_cache = KMEM_CACHE(encryption_ctx, 0);
- if (!encryption_ctx_cache)
- return -ENOMEM;
- decryption_ctx_cache = KMEM_CACHE(decryption_ctx, 0);
- if (!decryption_ctx_cache) {
- kmem_cache_destroy(encryption_ctx_cache);
- return -ENOMEM;
- }
- return 0;
-}
-
-void packet_deinit_data_caches(void)
-{
- kmem_cache_destroy(encryption_ctx_cache);
- kmem_cache_destroy(decryption_ctx_cache);
-}
-#endif
-
-/* This is RFC6479, a replay detection bitmap algorithm that avoids bitshifts */
-static inline bool counter_validate(union noise_counter *counter, u64 their_counter)
-{
- bool ret = false;
- unsigned long index, index_current, top, i;
- spin_lock_bh(&counter->receive.lock);
-
- if (unlikely(counter->receive.counter >= REJECT_AFTER_MESSAGES + 1 || their_counter >= REJECT_AFTER_MESSAGES))
- goto out;
-
- ++their_counter;
-
- if (unlikely((COUNTER_WINDOW_SIZE + their_counter) < counter->receive.counter))
- goto out;
-
- index = their_counter >> ilog2(BITS_PER_LONG);
-
- if (likely(their_counter > counter->receive.counter)) {
- index_current = counter->receive.counter >> ilog2(BITS_PER_LONG);
- top = min_t(unsigned long, index - index_current, COUNTER_BITS_TOTAL / BITS_PER_LONG);
- for (i = 1; i <= top; ++i)
- counter->receive.backtrack[(i + index_current) & ((COUNTER_BITS_TOTAL / BITS_PER_LONG) - 1)] = 0;
- counter->receive.counter = their_counter;
- }
-
- index &= (COUNTER_BITS_TOTAL / BITS_PER_LONG) - 1;
- ret = !test_and_set_bit(their_counter & (BITS_PER_LONG - 1), &counter->receive.backtrack[index]);
-
-out:
- spin_unlock_bh(&counter->receive.lock);
- return ret;
-}
-#include "selftest/counter.h"
-
-static inline unsigned int skb_padding(struct sk_buff *skb)
-{
- /* We do this modulo business with the MTU, just in case the networking layer
- * gives us a packet that's bigger than the MTU. Now that we support GSO, this
- * shouldn't be a real problem, and this can likely be removed. But, caution! */
- unsigned int last_unit = skb->len % skb->dev->mtu;
- unsigned int padded_size = (last_unit + MESSAGE_PADDING_MULTIPLE - 1) & ~(MESSAGE_PADDING_MULTIPLE - 1);
- if (padded_size > skb->dev->mtu)
- padded_size = skb->dev->mtu;
- return padded_size - last_unit;
-}
-
-static inline void skb_reset(struct sk_buff *skb)
-{
- skb_scrub_packet(skb, false);
- memset(&skb->headers_start, 0, offsetof(struct sk_buff, headers_end) - offsetof(struct sk_buff, headers_start));
- skb->queue_mapping = 0;
- skb->nohdr = 0;
- skb->peeked = 0;
- skb->mac_len = 0;
- skb->dev = NULL;
-#ifdef CONFIG_NET_SCHED
- skb->tc_index = 0;
- skb_reset_tc(skb);
-#endif
- skb->hdr_len = skb_headroom(skb);
- skb_reset_mac_header(skb);
- skb_reset_network_header(skb);
- skb_probe_transport_header(skb, 0);
- skb_reset_inner_headers(skb);
-}
-
-static inline bool skb_encrypt(struct sk_buff *skb, struct noise_keypair *keypair, bool have_simd)
-{
- struct scatterlist sg[MAX_SKB_FRAGS * 2 + 1];
- struct message_data *header;
- unsigned int padding_len, plaintext_len, trailer_len;
- int num_frags;
- struct sk_buff *trailer;
-
- /* Store the ds bit in the cb */
- PACKET_CB(skb)->ds = ip_tunnel_ecn_encap(0 /* No outer TOS: no leak. TODO: should we use flowi->tos as outer? */, ip_hdr(skb), skb);
-
- /* Calculate lengths */
- padding_len = skb_padding(skb);
- trailer_len = padding_len + noise_encrypted_len(0);
- plaintext_len = skb->len + padding_len;
-
- /* Expand data section to have room for padding and auth tag */
- num_frags = skb_cow_data(skb, trailer_len, &trailer);
- if (unlikely(num_frags < 0 || num_frags > ARRAY_SIZE(sg)))
- return false;
-
- /* Set the padding to zeros, and make sure it and the auth tag are part of the skb */
- memset(skb_tail_pointer(trailer), 0, padding_len);
-
- /* Expand head section to have room for our header and the network stack's headers. */
- if (unlikely(skb_cow_head(skb, DATA_PACKET_HEAD_ROOM) < 0))
- return false;
-
- /* We have to remember to add the checksum to the innerpacket, in case the receiver forwards it. */
- if (likely(!skb_checksum_setup(skb, true)))
- skb_checksum_help(skb);
-
- /* Only after checksumming can we safely add on the padding at the end and the header. */
- header = (struct message_data *)skb_push(skb, sizeof(struct message_data));
- header->header.type = cpu_to_le32(MESSAGE_DATA);
- header->key_idx = keypair->remote_index;
- header->counter = cpu_to_le64(PACKET_CB(skb)->nonce);
- pskb_put(skb, trailer, trailer_len);
-
- /* Now we can encrypt the scattergather segments */
- sg_init_table(sg, num_frags);
- if (skb_to_sgvec(skb, sg, sizeof(struct message_data), noise_encrypted_len(plaintext_len)) <= 0)
- return false;
- return chacha20poly1305_encrypt_sg(sg, sg, plaintext_len, NULL, 0, PACKET_CB(skb)->nonce, keypair->sending.key, have_simd);
-}
-
-static inline bool skb_decrypt(struct sk_buff *skb, struct noise_symmetric_key *key)
-{
- struct scatterlist sg[MAX_SKB_FRAGS * 2 + 1];
- struct sk_buff *trailer;
- int num_frags;
-
- if (unlikely(!key))
- return false;
-
- if (unlikely(!key->is_valid || time_is_before_eq_jiffies64(key->birthdate + REJECT_AFTER_TIME) || key->counter.receive.counter >= REJECT_AFTER_MESSAGES)) {
- key->is_valid = false;
- return false;
- }
-
- PACKET_CB(skb)->nonce = le64_to_cpu(((struct message_data *)skb->data)->counter);
- skb_pull(skb, sizeof(struct message_data));
- num_frags = skb_cow_data(skb, 0, &trailer);
- if (unlikely(num_frags < 0 || num_frags > ARRAY_SIZE(sg)))
- return false;
-
- sg_init_table(sg, num_frags);
- if (skb_to_sgvec(skb, sg, 0, skb->len) <= 0)
- return false;
-
- if (!chacha20poly1305_decrypt_sg(sg, sg, skb->len, NULL, 0, PACKET_CB(skb)->nonce, key->key))
- return false;
-
- return !pskb_trim(skb, skb->len - noise_encrypted_len(0));
-}
-
-static inline bool get_encryption_nonce(u64 *nonce, struct noise_symmetric_key *key)
-{
- if (unlikely(!key))
- return false;
-
- if (unlikely(!key->is_valid || time_is_before_eq_jiffies64(key->birthdate + REJECT_AFTER_TIME))) {
- key->is_valid = false;
- return false;
- }
-
- *nonce = atomic64_inc_return(&key->counter.counter) - 1;
- if (*nonce >= REJECT_AFTER_MESSAGES) {
- key->is_valid = false;
- return false;
- }
-
- return true;
-}
-
-static inline void queue_encrypt_reset(struct sk_buff_head *queue, struct noise_keypair *keypair)
-{
- struct sk_buff *skb, *tmp;
- bool have_simd = chacha20poly1305_init_simd();
- skb_queue_walk_safe (queue, skb, tmp) {
- if (unlikely(!skb_encrypt(skb, keypair, have_simd))) {
- __skb_unlink(skb, queue);
- kfree_skb(skb);
- continue;
- }
- skb_reset(skb);
- }
- chacha20poly1305_deinit_simd(have_simd);
- noise_keypair_put(keypair);
-}
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
-static void begin_parallel_encryption(struct padata_priv *padata)
-{
- struct encryption_ctx *ctx = container_of(padata, struct encryption_ctx, padata);
-#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && defined(CONFIG_ARM)
- local_bh_enable();
-#endif
- queue_encrypt_reset(&ctx->queue, ctx->keypair);
-#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && defined(CONFIG_ARM)
- local_bh_disable();
-#endif
- padata_do_serial(padata);
-}
-
-static void finish_parallel_encryption(struct padata_priv *padata)
-{
- struct encryption_ctx *ctx = container_of(padata, struct encryption_ctx, padata);
- packet_create_data_done(&ctx->queue, ctx->peer);
- atomic_dec(&ctx->peer->parallel_encryption_inflight);
- peer_put(ctx->peer);
- kmem_cache_free(encryption_ctx_cache, ctx);
-}
-
-static inline unsigned int choose_cpu(__le32 key)
-{
- unsigned int cpu_index, cpu, cb_cpu;
-
- /* This ensures that packets encrypted to the same key are sent in-order. */
- cpu_index = ((__force unsigned int)key) % cpumask_weight(cpu_online_mask);
- cb_cpu = cpumask_first(cpu_online_mask);
- for (cpu = 0; cpu < cpu_index; ++cpu)
- cb_cpu = cpumask_next(cb_cpu, cpu_online_mask);
-
- return cb_cpu;
-}
-#endif
-
-int packet_create_data(struct sk_buff_head *queue, struct wireguard_peer *peer)
-{
- int ret = -ENOKEY;
- struct noise_keypair *keypair;
- struct sk_buff *skb;
-
- rcu_read_lock_bh();
- keypair = noise_keypair_get(rcu_dereference_bh(peer->keypairs.current_keypair));
- rcu_read_unlock_bh();
- if (unlikely(!keypair))
- return ret;
-
- skb_queue_walk (queue, skb) {
- if (unlikely(!get_encryption_nonce(&PACKET_CB(skb)->nonce, &keypair->sending)))
- goto err;
-
- /* After the first time through the loop, if we've suceeded with a legitimate nonce,
- * then we don't want a -ENOKEY error if subsequent nonces fail. Rather, if this
- * condition arises, we simply want error out hard, and drop the entire queue. This
- * is partially lazy programming and TODO: this could be made to only requeue the
- * ones that had no nonce. But I'm not sure it's worth the added complexity, given
- * how rarely that condition should arise. */
- ret = -EPIPE;
- }
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
- if ((skb_queue_len(queue) > 1 || queue->next->len > 256 || atomic_read(&peer->parallel_encryption_inflight) > 0) && cpumask_weight(cpu_online_mask) > 1) {
- struct encryption_ctx *ctx = kmem_cache_alloc(encryption_ctx_cache, GFP_ATOMIC);
- if (!ctx)
- goto serial_encrypt;
- skb_queue_head_init(&ctx->queue);
- skb_queue_splice_init(queue, &ctx->queue);
- memset(&ctx->padata, 0, sizeof(ctx->padata));
- ctx->padata.parallel = begin_parallel_encryption;
- ctx->padata.serial = finish_parallel_encryption;
- ctx->keypair = keypair;
- ctx->peer = peer_rcu_get(peer);
- ret = -EBUSY;
- if (unlikely(!ctx->peer))
- goto err_parallel;
- atomic_inc(&peer->parallel_encryption_inflight);
- if (unlikely(padata_do_parallel(peer->device->encrypt_pd, &ctx->padata, choose_cpu(keypair->remote_index)))) {
- atomic_dec(&peer->parallel_encryption_inflight);
- peer_put(ctx->peer);
-err_parallel:
- skb_queue_splice(&ctx->queue, queue);
- kmem_cache_free(encryption_ctx_cache, ctx);
- goto err;
- }
- } else
-serial_encrypt:
-#endif
- {
- queue_encrypt_reset(queue, keypair);
- packet_create_data_done(queue, peer);
- }
- return 0;
-
-err:
- noise_keypair_put(keypair);
- return ret;
-}
-
-static void begin_decrypt_packet(struct decryption_ctx *ctx)
-{
- if (unlikely(socket_endpoint_from_skb(&ctx->endpoint, ctx->skb) < 0 || !skb_decrypt(ctx->skb, &ctx->keypair->receiving))) {
- peer_put(ctx->keypair->entry.peer);
- noise_keypair_put(ctx->keypair);
- dev_kfree_skb(ctx->skb);
- ctx->skb = NULL;
- }
-}
-
-static void finish_decrypt_packet(struct decryption_ctx *ctx)
-{
- bool used_new_key;
-
- if (!ctx->skb)
- return;
-
- if (unlikely(!counter_validate(&ctx->keypair->receiving.counter, PACKET_CB(ctx->skb)->nonce))) {
- net_dbg_ratelimited("%s: Packet has invalid nonce %Lu (max %Lu)\n", ctx->keypair->entry.peer->device->dev->name, PACKET_CB(ctx->skb)->nonce, ctx->keypair->receiving.counter.receive.counter);
- peer_put(ctx->keypair->entry.peer);
- noise_keypair_put(ctx->keypair);
- dev_kfree_skb(ctx->skb);
- return;
- }
-
- used_new_key = noise_received_with_keypair(&ctx->keypair->entry.peer->keypairs, ctx->keypair);
- skb_reset(ctx->skb);
- packet_consume_data_done(ctx->skb, ctx->keypair->entry.peer, &ctx->endpoint, used_new_key);
- noise_keypair_put(ctx->keypair);
-}
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
-static void begin_parallel_decryption(struct padata_priv *padata)
-{
- struct decryption_ctx *ctx = container_of(padata, struct decryption_ctx, padata);
-#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && defined(CONFIG_ARM)
- local_bh_enable();
-#endif
- begin_decrypt_packet(ctx);
-#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && defined(CONFIG_ARM)
- local_bh_disable();
-#endif
- padata_do_serial(padata);
-}
-
-static void finish_parallel_decryption(struct padata_priv *padata)
-{
- struct decryption_ctx *ctx = container_of(padata, struct decryption_ctx, padata);
- finish_decrypt_packet(ctx);
- kmem_cache_free(decryption_ctx_cache, ctx);
-}
-#endif
-
-void packet_consume_data(struct sk_buff *skb, struct wireguard_device *wg)
-{
- struct noise_keypair *keypair;
- __le32 idx = ((struct message_data *)skb->data)->key_idx;
-
- rcu_read_lock_bh();
- keypair = noise_keypair_get((struct noise_keypair *)index_hashtable_lookup(&wg->index_hashtable, INDEX_HASHTABLE_KEYPAIR, idx));
- rcu_read_unlock_bh();
- if (unlikely(!keypair))
- goto err;
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
- if (cpumask_weight(cpu_online_mask) > 1) {
- struct decryption_ctx *ctx = kmem_cache_alloc(decryption_ctx_cache, GFP_ATOMIC);
- if (unlikely(!ctx))
- goto err_peer;
- ctx->skb = skb;
- ctx->keypair = keypair;
- memset(&ctx->padata, 0, sizeof(ctx->padata));
- ctx->padata.parallel = begin_parallel_decryption;
- ctx->padata.serial = finish_parallel_decryption;
- if (unlikely(padata_do_parallel(wg->decrypt_pd, &ctx->padata, choose_cpu(idx)))) {
- kmem_cache_free(decryption_ctx_cache, ctx);
- goto err_peer;
- }
- } else
-#endif
- {
- struct decryption_ctx ctx = {
- .skb = skb,
- .keypair = keypair
- };
- begin_decrypt_packet(&ctx);
- finish_decrypt_packet(&ctx);
- }
- return;
-
-#ifdef CONFIG_WIREGUARD_PARALLEL
-err_peer:
- peer_put(keypair->entry.peer);
- noise_keypair_put(keypair);
-#endif
-err:
- dev_kfree_skb(skb);
-}