aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--include/linux/tcp.h7
-rw-r--r--include/net/tcp.h10
-rw-r--r--net/Kconfig2
-rw-r--r--net/ipv4/tcp_fastopen.c97
4 files changed, 36 insertions, 80 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index c23019a3b264..9ea0e71f5c6a 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -58,12 +58,7 @@ static inline unsigned int tcp_optlen(const struct sk_buff *skb)
/* TCP Fast Open Cookie as stored in memory */
struct tcp_fastopen_cookie {
- union {
- u8 val[TCP_FASTOPEN_COOKIE_MAX];
-#if IS_ENABLED(CONFIG_IPV6)
- struct in6_addr addr;
-#endif
- };
+ u64 val[TCP_FASTOPEN_COOKIE_MAX / sizeof(u64)];
s8 len;
bool exp; /* In RFC6994 experimental option format */
};
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 96e0e53ff440..184930b02779 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1628,9 +1628,9 @@ bool tcp_fastopen_defer_connect(struct sock *sk, int *err);
/* Fastopen key context */
struct tcp_fastopen_context {
- struct crypto_cipher *tfm[TCP_FASTOPEN_KEY_MAX];
- __u8 key[TCP_FASTOPEN_KEY_BUF_LENGTH];
- struct rcu_head rcu;
+ __u8 key[TCP_FASTOPEN_KEY_MAX][TCP_FASTOPEN_KEY_LENGTH];
+ int num;
+ struct rcu_head rcu;
};
extern unsigned int sysctl_tcp_fastopen_blackhole_timeout;
@@ -1665,9 +1665,7 @@ bool tcp_fastopen_cookie_match(const struct tcp_fastopen_cookie *foc,
static inline
int tcp_fastopen_context_len(const struct tcp_fastopen_context *ctx)
{
- if (ctx->tfm[1])
- return 2;
- return 1;
+ return ctx->num;
}
/* Latencies incurred by various limits for a sender. They are
diff --git a/net/Kconfig b/net/Kconfig
index d122f53c6fa2..57f51a279ad6 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -67,8 +67,6 @@ source "net/xdp/Kconfig"
config INET
bool "TCP/IP networking"
- select CRYPTO
- select CRYPTO_AES
---help---
These are the protocols used on the Internet and on most local
Ethernets. It is highly recommended to say Y here (this will enlarge
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 7d19fa4c8121..46b67128e1ca 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -7,6 +7,7 @@
#include <linux/tcp.h>
#include <linux/rcupdate.h>
#include <linux/rculist.h>
+#include <linux/siphash.h>
#include <net/inetpeer.h>
#include <net/tcp.h>
@@ -37,14 +38,8 @@ static void tcp_fastopen_ctx_free(struct rcu_head *head)
{
struct tcp_fastopen_context *ctx =
container_of(head, struct tcp_fastopen_context, rcu);
- int i;
- /* We own ctx, thus no need to hold the Fastopen-lock */
- for (i = 0; i < TCP_FASTOPEN_KEY_MAX; i++) {
- if (ctx->tfm[i])
- crypto_free_cipher(ctx->tfm[i]);
- }
- kfree(ctx);
+ kzfree(ctx);
}
void tcp_fastopen_destroy_cipher(struct sock *sk)
@@ -72,41 +67,6 @@ void tcp_fastopen_ctx_destroy(struct net *net)
call_rcu(&ctxt->rcu, tcp_fastopen_ctx_free);
}
-static struct tcp_fastopen_context *tcp_fastopen_alloc_ctx(void *primary_key,
- void *backup_key,
- unsigned int len)
-{
- struct tcp_fastopen_context *new_ctx;
- void *key = primary_key;
- int err, i;
-
- new_ctx = kmalloc(sizeof(*new_ctx), GFP_KERNEL);
- if (!new_ctx)
- return ERR_PTR(-ENOMEM);
- for (i = 0; i < TCP_FASTOPEN_KEY_MAX; i++)
- new_ctx->tfm[i] = NULL;
- for (i = 0; i < (backup_key ? 2 : 1); i++) {
- new_ctx->tfm[i] = crypto_alloc_cipher("aes", 0, 0);
- if (IS_ERR(new_ctx->tfm[i])) {
- err = PTR_ERR(new_ctx->tfm[i]);
- new_ctx->tfm[i] = NULL;
- pr_err("TCP: TFO aes cipher alloc error: %d\n", err);
- goto out;
- }
- err = crypto_cipher_setkey(new_ctx->tfm[i], key, len);
- if (err) {
- pr_err("TCP: TFO cipher key error: %d\n", err);
- goto out;
- }
- memcpy(&new_ctx->key[i * TCP_FASTOPEN_KEY_LENGTH], key, len);
- key = backup_key;
- }
- return new_ctx;
-out:
- tcp_fastopen_ctx_free(&new_ctx->rcu);
- return ERR_PTR(err);
-}
-
int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk,
void *primary_key, void *backup_key,
unsigned int len)
@@ -115,11 +75,20 @@ int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk,
struct fastopen_queue *q;
int err = 0;
- ctx = tcp_fastopen_alloc_ctx(primary_key, backup_key, len);
- if (IS_ERR(ctx)) {
- err = PTR_ERR(ctx);
+ ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx) {
+ err = -ENOMEM;
goto out;
}
+
+ memcpy(ctx->key[0], primary_key, len);
+ if (backup_key) {
+ memcpy(ctx->key[1], backup_key, len);
+ ctx->num = 2;
+ } else {
+ ctx->num = 1;
+ }
+
spin_lock(&net->ipv4.tcp_fastopen_ctx_lock);
if (sk) {
q = &inet_csk(sk)->icsk_accept_queue.fastopenq;
@@ -141,31 +110,30 @@ out:
static bool __tcp_fastopen_cookie_gen_cipher(struct request_sock *req,
struct sk_buff *syn,
- struct crypto_cipher *tfm,
+ const u8 *key,
struct tcp_fastopen_cookie *foc)
{
+ BUILD_BUG_ON(TCP_FASTOPEN_KEY_LENGTH != sizeof(siphash_key_t));
+ BUILD_BUG_ON(TCP_FASTOPEN_COOKIE_SIZE != sizeof(u64));
+
if (req->rsk_ops->family == AF_INET) {
const struct iphdr *iph = ip_hdr(syn);
- __be32 path[4] = { iph->saddr, iph->daddr, 0, 0 };
- crypto_cipher_encrypt_one(tfm, foc->val, (void *)path);
+ foc->val[0] = siphash(&iph->saddr,
+ sizeof(iph->saddr) +
+ sizeof(iph->daddr),
+ (const siphash_key_t *)key);
foc->len = TCP_FASTOPEN_COOKIE_SIZE;
return true;
}
-
#if IS_ENABLED(CONFIG_IPV6)
if (req->rsk_ops->family == AF_INET6) {
const struct ipv6hdr *ip6h = ipv6_hdr(syn);
- struct tcp_fastopen_cookie tmp;
- struct in6_addr *buf;
- int i;
-
- crypto_cipher_encrypt_one(tfm, tmp.val,
- (void *)&ip6h->saddr);
- buf = &tmp.addr;
- for (i = 0; i < 4; i++)
- buf->s6_addr32[i] ^= ip6h->daddr.s6_addr32[i];
- crypto_cipher_encrypt_one(tfm, foc->val, (void *)buf);
+
+ foc->val[0] = siphash(&ip6h->saddr,
+ sizeof(ip6h->saddr) +
+ sizeof(ip6h->daddr),
+ (const siphash_key_t *)key);
foc->len = TCP_FASTOPEN_COOKIE_SIZE;
return true;
}
@@ -173,11 +141,8 @@ static bool __tcp_fastopen_cookie_gen_cipher(struct request_sock *req,
return false;
}
-/* Generate the fastopen cookie by doing aes128 encryption on both
- * the source and destination addresses. Pad 0s for IPv4 or IPv4-mapped-IPv6
- * addresses. For the longer IPv6 addresses use CBC-MAC.
- *
- * XXX (TFO) - refactor when TCP_FASTOPEN_COOKIE_SIZE != AES_BLOCK_SIZE.
+/* Generate the fastopen cookie by applying SipHash to both the source and
+ * destination addresses.
*/
static void tcp_fastopen_cookie_gen(struct sock *sk,
struct request_sock *req,
@@ -189,7 +154,7 @@ static void tcp_fastopen_cookie_gen(struct sock *sk,
rcu_read_lock();
ctx = tcp_fastopen_get_ctx(sk);
if (ctx)
- __tcp_fastopen_cookie_gen_cipher(req, syn, ctx->tfm[0], foc);
+ __tcp_fastopen_cookie_gen_cipher(req, syn, ctx->key[0], foc);
rcu_read_unlock();
}
@@ -253,7 +218,7 @@ static int tcp_fastopen_cookie_gen_check(struct sock *sk,
if (!ctx)
goto out;
for (i = 0; i < tcp_fastopen_context_len(ctx); i++) {
- __tcp_fastopen_cookie_gen_cipher(req, syn, ctx->tfm[i], foc);
+ __tcp_fastopen_cookie_gen_cipher(req, syn, ctx->key[i], foc);
if (tcp_fastopen_cookie_match(foc, orig)) {
ret = i + 1;
goto out;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.