summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_fastopen.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv4/tcp_fastopen.c')
-rw-r--r--net/ipv4/tcp_fastopen.c57
1 files changed, 43 insertions, 14 deletions
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 9b947a9aaf6e..62e48cf84e60 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -72,27 +72,58 @@ error: kfree(ctx);
return err;
}
-/* Computes the fastopen cookie for the IP path.
- * The path is a 128 bits long (pad with zeros for IPv4).
- *
- * The caller must check foc->len to determine if a valid cookie
- * has been generated successfully.
-*/
-void tcp_fastopen_cookie_gen(__be32 src, __be32 dst,
- struct tcp_fastopen_cookie *foc)
+static bool __tcp_fastopen_cookie_gen(const void *path,
+ struct tcp_fastopen_cookie *foc)
{
- __be32 path[4] = { src, dst, 0, 0 };
struct tcp_fastopen_context *ctx;
+ bool ok = false;
tcp_fastopen_init_key_once(true);
rcu_read_lock();
ctx = rcu_dereference(tcp_fastopen_ctx);
if (ctx) {
- crypto_cipher_encrypt_one(ctx->tfm, foc->val, (__u8 *)path);
+ crypto_cipher_encrypt_one(ctx->tfm, foc->val, path);
foc->len = TCP_FASTOPEN_COOKIE_SIZE;
+ ok = true;
}
rcu_read_unlock();
+ return ok;
+}
+
+/* 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.
+ */
+static bool tcp_fastopen_cookie_gen(struct request_sock *req,
+ struct sk_buff *syn,
+ struct tcp_fastopen_cookie *foc)
+{
+ if (req->rsk_ops->family == AF_INET) {
+ const struct iphdr *iph = ip_hdr(syn);
+
+ __be32 path[4] = { iph->saddr, iph->daddr, 0, 0 };
+ return __tcp_fastopen_cookie_gen(path, foc);
+ }
+
+#if IS_ENABLED(CONFIG_IPV6)
+ if (req->rsk_ops->family == AF_INET6) {
+ const struct ipv6hdr *ip6h = ipv6_hdr(syn);
+ struct tcp_fastopen_cookie tmp;
+
+ if (__tcp_fastopen_cookie_gen(&ip6h->saddr, &tmp)) {
+ struct in6_addr *buf = (struct in6_addr *) tmp.val;
+ int i = 4;
+
+ for (i = 0; i < 4; i++)
+ buf->s6_addr32[i] ^= ip6h->daddr.s6_addr32[i];
+ return __tcp_fastopen_cookie_gen(buf, foc);
+ }
+ }
+#endif
+ return false;
}
static bool tcp_fastopen_create_child(struct sock *sk,
@@ -234,10 +265,8 @@ bool tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
if (syn_data && (sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD))
goto fastopen;
- tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr,
- ip_hdr(skb)->daddr, &valid_foc);
-
- if (foc->len == TCP_FASTOPEN_COOKIE_SIZE &&
+ if (tcp_fastopen_cookie_gen(req, skb, &valid_foc) &&
+ foc->len == TCP_FASTOPEN_COOKIE_SIZE &&
foc->len == valid_foc.len &&
!memcmp(foc->val, valid_foc.val, foc->len)) {
/* Cookie is valid. Create a (full) child socket to accept