diff options
Diffstat (limited to 'net/ipv4/tcp_fastopen.c')
| -rw-r--r-- | net/ipv4/tcp_fastopen.c | 57 |
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 |