Now when the new request socket is created from the listening socket, it's recorded what MKT was used by the peer. tcp_rsk_used_ao() is a new helper for checking if TCP-AO option was used to create the request socket. tcp_ao_copy_all_matching() will copy all keys that match the peer on the request socket, as well as preparing them for the usage (creating traffic keys). Co-developed-by: Francesco Ruggeri <fruggeri@xxxxxxxxxx> Signed-off-by: Francesco Ruggeri <fruggeri@xxxxxxxxxx> Co-developed-by: Salam Noureddine <noureddine@xxxxxxxxxx> Signed-off-by: Salam Noureddine <noureddine@xxxxxxxxxx> Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx> --- include/linux/tcp.h | 18 ++++ include/net/tcp.h | 7 ++ include/net/tcp_ao.h | 22 +++++ net/ipv4/syncookies.c | 2 + net/ipv4/tcp_ao.c | 187 +++++++++++++++++++++++++++++++++++++++ net/ipv4/tcp_input.c | 16 ++++ net/ipv4/tcp_ipv4.c | 63 +++++++++++-- net/ipv4/tcp_minisocks.c | 10 +++ net/ipv4/tcp_output.c | 36 +++++--- net/ipv6/syncookies.c | 2 + net/ipv6/tcp_ao.c | 21 +++++ net/ipv6/tcp_ipv6.c | 78 +++++++++++++--- 12 files changed, 433 insertions(+), 29 deletions(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 6630a8195ea6..cbaf9ca25974 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -165,6 +165,11 @@ struct tcp_request_sock { * after data-in-SYN. */ u8 syn_tos; +#ifdef CONFIG_TCP_AO + u8 ao_keyid; + u8 ao_rcv_next; + u8 maclen; +#endif }; static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) @@ -172,6 +177,19 @@ static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) return (struct tcp_request_sock *)req; } +static inline bool tcp_rsk_used_ao(const struct request_sock *req) +{ + /* The real length of MAC is saved in the request socket, + * signing anything with zero-length makes no sense, so here is + * a little hack.. + */ +#ifndef CONFIG_TCP_AO + return false; +#else + return tcp_rsk(req)->maclen != 0; +#endif +} + struct tcp_sock { /* inet_connection_sock has to be the first member of tcp_sock */ struct inet_connection_sock inet_conn; diff --git a/include/net/tcp.h b/include/net/tcp.h index d2395ae7484c..bda03d4925ed 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2113,6 +2113,13 @@ struct tcp_request_sock_ops { const struct sock *sk, const struct sk_buff *skb); #endif +#ifdef CONFIG_TCP_AO + struct tcp_ao_key *(*ao_lookup)(const struct sock *sk, + struct request_sock *req, + int sndid, int rcvid); + int (*ao_calc_key)(struct tcp_ao_key *mkt, u8 *key, + struct request_sock *sk); +#endif #ifdef CONFIG_SYN_COOKIES __u32 (*cookie_init_seq)(const struct sk_buff *skb, __u16 *mss); diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index 9804881fd2bf..e93db866bd44 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -116,6 +116,9 @@ int tcp_ao_hash_skb(unsigned short int family, int tcp_parse_ao(struct sock *sk, int cmd, unsigned short int family, sockptr_t optval, int optlen); struct tcp_ao_key *tcp_ao_do_lookup_sndid(const struct sock *sk, u8 keyid); +int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk, + struct request_sock *req, struct sk_buff *skb, + int family); int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx, unsigned int len); void tcp_ao_destroy_sock(struct sock *sk, bool twsk); @@ -139,6 +142,11 @@ struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, int tcp_v4_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, const struct sock *sk, __be32 sisn, __be32 disn, bool send); +int tcp_v4_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, + struct request_sock *req); +struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk, + struct request_sock *req, + int sndid, int rcvid); int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, const struct sock *sk, const struct sk_buff *skb, const u8 *tkey, int hash_offset, u32 sne); @@ -149,9 +157,17 @@ int tcp_v6_ao_hash_pseudoheader(struct crypto_pool_ahash *hp, int tcp_v6_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, const struct sock *sk, __be32 sisn, __be32 disn, bool send); +int tcp_v6_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, + struct request_sock *req); +struct tcp_ao_key *tcp_v6_ao_do_lookup(const struct sock *sk, + const struct in6_addr *addr, + int sndid, int rcvid); struct tcp_ao_key *tcp_v6_ao_lookup(const struct sock *sk, struct sock *addr_sk, int sndid, int rcvid); +struct tcp_ao_key *tcp_v6_ao_lookup_rsk(const struct sock *sk, + struct request_sock *req, + int sndid, int rcvid); int tcp_v6_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, const struct sock *sk, const struct sk_buff *skb, const u8 *tkey, int hash_offset, u32 sne); @@ -164,6 +180,12 @@ void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, unsigned short int family); #else /* CONFIG_TCP_AO */ +static inline void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, + struct tcp_request_sock *treq, + unsigned short int family) +{ +} + static inline struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, const union tcp_ao_addr *addr, int family, int sndid, int rcvid, u16 port) diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index 942d2dfa1115..83801d7c5b02 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -395,6 +395,8 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb) treq->snt_synack = 0; treq->tfo_listener = false; + tcp_ao_syncookie(sk, skb, treq, AF_INET); + if (IS_ENABLED(CONFIG_SMC)) ireq->smc_ok = 0; diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 09d5cee7c6d7..c9d3e29a28f1 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -52,6 +52,21 @@ int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx, return 1; } +static struct tcp_ao_key *tcp_ao_do_lookup_keyid(struct tcp_ao_info *ao, + int sndid, int rcvid) +{ + struct tcp_ao_key *key; + + hlist_for_each_entry_rcu(key, &ao->head, node) { + if ((sndid >= 0 && key->sndid != sndid) || + (rcvid >= 0 && key->rcvid != rcvid)) + continue; + return key; + } + + return NULL; +} + static struct tcp_ao_key *tcp_ao_do_lookup_rcvid(struct sock *sk, u8 keyid) { struct tcp_sock *tp = tcp_sk(sk); @@ -194,6 +209,23 @@ static void tcp_ao_link_mkt(struct tcp_ao_info *ao, struct tcp_ao_key *mkt) hlist_add_head_rcu(&mkt->node, &ao->head); } +static struct tcp_ao_key *tcp_ao_copy_key(struct sock *sk, + struct tcp_ao_key *key) +{ + struct tcp_ao_key *new_key; + + new_key = sock_kmalloc(sk, tcp_ao_sizeof_key(key), + GFP_ATOMIC); + if (!new_key) + return NULL; + + *new_key = *key; + INIT_HLIST_NODE(&new_key->node); + crypto_pool_add(new_key->crypto_pool_id); + + return new_key; +} + static void tcp_ao_key_free_rcu(struct rcu_head *head) { struct tcp_ao_key *key = container_of(head, struct tcp_ao_key, rcu); @@ -291,6 +323,18 @@ int tcp_v4_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, htons(sk->sk_num), disn, sisn); } +int tcp_v4_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, + struct request_sock *req) +{ + struct inet_request_sock *ireq = inet_rsk(req); + + return tcp_v4_ao_calc_key(mkt, key, + ireq->ir_loc_addr, ireq->ir_rmt_addr, + htons(ireq->ir_num), ireq->ir_rmt_port, + htonl(tcp_rsk(req)->snt_isn), + htonl(tcp_rsk(req)->rcv_isn)); +} + static int tcp_v4_ao_hash_pseudoheader(struct crypto_pool_ahash *hp, __be32 daddr, __be32 saddr, int nbytes) @@ -560,6 +604,16 @@ int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, tkey, hash_offset, sne); } +struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk, + struct request_sock *req, + int sndid, int rcvid) +{ + union tcp_ao_addr *addr = + (union tcp_ao_addr *)&inet_rsk(req)->ir_rmt_addr; + + return tcp_ao_do_lookup(sk, addr, AF_INET, sndid, rcvid, 0); +} + struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, int sndid, int rcvid) { @@ -568,6 +622,51 @@ struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, return tcp_ao_do_lookup(sk, addr, AF_INET, sndid, rcvid, 0); } +static struct tcp_ao_key *tcp_ao_inbound_lookup(unsigned short int family, + const struct sock *sk, const struct sk_buff *skb, + int sndid, int rcvid) +{ + if (family == AF_INET) { + const struct iphdr *iph = ip_hdr(skb); + + return tcp_ao_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr, + AF_INET, sndid, rcvid, 0); + } else { + const struct ipv6hdr *iph = ipv6_hdr(skb); + + return tcp_ao_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr, + AF_INET6, sndid, rcvid, 0); + } +} + +/* Returns maclen of requested key if found */ +void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, + struct tcp_request_sock *treq, + unsigned short int family) +{ + const struct tcphdr *th = tcp_hdr(skb); + const struct tcp_ao_hdr *aoh; + struct tcp_ao_key *key; + + treq->maclen = 0; + + /* Shouldn't fail as this has been called on this packet + * in tcp_inbound_hash() + */ + tcp_parse_auth_options(th, NULL, &aoh); + if (!aoh) + return; + + key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid); + if (!key) + /* Key not found, continue without TCP-AO */ + return; + + treq->ao_rcv_next = aoh->keyid; + treq->ao_keyid = aoh->rnext_keyid; + treq->maclen = tcp_ao_maclen(key); +} + int tcp_ao_cache_traffic_keys(const struct sock *sk, struct tcp_ao_info *ao, struct tcp_ao_key *ao_key) { @@ -665,6 +764,94 @@ void tcp_ao_finish_connect(struct sock *sk, struct sk_buff *skb) } } +int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk, + struct request_sock *req, struct sk_buff *skb, + int family) +{ + struct tcp_ao_info *ao; + struct tcp_ao_info *new_ao; + struct tcp_ao_key *key, *new_key, *first_key; + struct hlist_node *n; + union tcp_ao_addr *addr; + bool match = false; + + ao = rcu_dereference(tcp_sk(sk)->ao_info); + if (!ao) + return 0; + + /* New socket without TCP-AO on it */ + if (!tcp_rsk_used_ao(req)) + return 0; + + new_ao = tcp_ao_alloc_info(GFP_ATOMIC, ao); + if (!new_ao) + return -ENOMEM; + new_ao->lisn = htonl(tcp_rsk(req)->snt_isn); + new_ao->risn = htonl(tcp_rsk(req)->rcv_isn); + + if (family == AF_INET) + addr = (union tcp_ao_addr *)&newsk->sk_daddr; +#if IS_ENABLED(CONFIG_IPV6) + else if (family == AF_INET6) + addr = (union tcp_ao_addr *)&newsk->sk_v6_daddr; +#endif + else + return -EOPNOTSUPP; + + hlist_for_each_entry_rcu(key, &ao->head, node) { + if (tcp_ao_key_cmp(key, addr, key->prefixlen, family, + -1, -1, 0)) + continue; + + new_key = tcp_ao_copy_key(newsk, key); + if (!new_key) + goto free_and_exit; + + tcp_ao_cache_traffic_keys(newsk, new_ao, new_key); + tcp_ao_link_mkt(new_ao, new_key); + match = true; + } + + if (match) { + struct hlist_node *key_head; + + key_head = rcu_dereference(hlist_first_rcu(&new_ao->head)); + first_key = hlist_entry_safe(key_head, struct tcp_ao_key, node); + + /* set current_key */ + key = tcp_ao_do_lookup_keyid(new_ao, tcp_rsk(req)->ao_keyid, -1); + if (key) + new_ao->current_key = key; + else + new_ao->current_key = first_key; + + /* set rnext_key */ + key = tcp_ao_do_lookup_keyid(new_ao, -1, tcp_rsk(req)->ao_rcv_next); + if (key) + new_ao->rnext_key = key; + else + new_ao->rnext_key = first_key; + + new_ao->snd_sne_seq = tcp_rsk(req)->snt_isn; + new_ao->rcv_sne_seq = tcp_rsk(req)->rcv_isn; + + sk_gso_disable(newsk); + rcu_assign_pointer(tcp_sk(newsk)->ao_info, new_ao); + } + + return 0; + +free_and_exit: + hlist_for_each_entry_safe(key, n, &new_ao->head, node) { + hlist_del(&key->node); + crypto_pool_release(key->crypto_pool_id); + atomic_sub(tcp_ao_sizeof_key(key), &newsk->sk_omem_alloc); + kfree(key); + } + kfree(new_ao); + return -ENOMEM; +} + static int tcp_ao_current_rnext(struct sock *sk, u16 tcpa_flags, u8 tcpa_sndid, u8 tcpa_rcvid) { diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a7c3823cd052..df3087c8179f 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -6935,6 +6935,10 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, struct flowi fl; u8 syncookies; +#ifdef CONFIG_TCP_AO + const struct tcp_ao_hdr *aoh; +#endif + syncookies = READ_ONCE(net->ipv4.sysctl_tcp_syncookies); /* TW buckets are converted to open requests without @@ -7020,6 +7024,18 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, inet_rsk(req)->ecn_ok = 0; } +#ifdef CONFIG_TCP_AO + /* TODO: Add an option to require TCP-AO signature */ + if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh)) + goto drop_and_release; /* Invalid TCP options */ + if (aoh) { + tcp_rsk(req)->maclen = aoh->length - sizeof(struct tcp_ao_hdr); + tcp_rsk(req)->ao_rcv_next = aoh->keyid; + tcp_rsk(req)->ao_keyid = aoh->rnext_keyid; + } else { + tcp_rsk(req)->maclen = 0; + } +#endif tcp_rsk(req)->snt_isn = isn; tcp_rsk(req)->txhash = net_tx_rndhash(); tcp_rsk(req)->syn_tos = TCP_SKB_CB(skb)->ip_dsfield; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index fcf61b5bc581..47325f148f29 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1088,30 +1088,73 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, struct request_sock *req) { + struct tcp_md5sig_key *md5_key = NULL; + struct tcp_ao_key *ao_key = NULL; const union tcp_md5_addr *addr; - int l3index; + u8 keyid = 0; +#ifdef CONFIG_TCP_AO + u8 traffic_key[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + const struct tcp_ao_hdr *aoh; +#else + u8 *traffic_key = NULL; +#endif /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV * sk->sk_state == TCP_SYN_RECV -> for Fast Open. */ u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt; + addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; + + if (tcp_rsk_used_ao(req)) { +#ifdef CONFIG_TCP_AO + /* Invalid TCP option size or twice included auth */ + if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh)) + return; + + if (!aoh) + return; + + ao_key = tcp_ao_do_lookup(sk, addr, AF_INET, + aoh->rnext_keyid, -1, 0); + if (unlikely(!ao_key)) { + /* Send ACK with any matching MKT for the peer */ + ao_key = tcp_ao_do_lookup(sk, addr, + AF_INET, -1, -1, 0); + /* Matching key disappeared (user removed the key?) + * let the handshake timeout. + */ + if (!ao_key) { + net_info_ratelimited("TCP-AO key for (%pI4, %d)->(%pI4, %d) suddenly disappeared, won't ACK new connection\n", + addr, + ntohs(tcp_hdr(skb)->source), + &ip_hdr(skb)->daddr, + ntohs(tcp_hdr(skb)->dest)); + return; + } + } + keyid = aoh->keyid; + tcp_v4_ao_calc_key_rsk(ao_key, traffic_key, req); +#endif + } else { + int l3index; + + l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; + md5_key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); + } /* RFC 7323 2.3 * The window field (SEG.WND) of every outgoing segment, with the * exception of <SYN> segments, MUST be right-shifted by * Rcv.Wind.Shift bits: */ - addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; - l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; tcp_v4_send_ack(sk, skb, seq, tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, req->ts_recent, 0, - tcp_md5_do_lookup(sk, l3index, addr, AF_INET), - NULL, NULL, 0, 0, + md5_key, ao_key, traffic_key, keyid, 0, inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, ip_hdr(skb)->tos); } @@ -1632,6 +1675,10 @@ const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { .req_md5_lookup = tcp_v4_md5_lookup, .calc_md5_hash = tcp_v4_md5_hash_skb, #endif +#ifdef CONFIG_TCP_AO + .ao_lookup = tcp_v4_ao_lookup_rsk, + .ao_calc_key = tcp_v4_ao_calc_key_rsk, +#endif #ifdef CONFIG_SYN_COOKIES .cookie_init_seq = cookie_v4_init_sequence, #endif @@ -1733,7 +1780,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, /* Copy over the MD5 key from the original socket */ addr = (union tcp_md5_addr *)&newinet->inet_daddr; key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); - if (key) { + if (key && !tcp_rsk_used_ao(req)) { /* * We're using one, so create a matching key * on the newsk structure. If we fail to get @@ -1744,6 +1791,10 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, sk_gso_disable(newsk); } #endif +#ifdef CONFIG_TCP_AO + if (tcp_ao_copy_all_matching(sk, newsk, req, skb, AF_INET)) + goto put_and_exit; /* OOM, release back memory */ +#endif if (__inet_inherit_port(sk, newsk) < 0) goto put_and_exit; diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 87cf3073b6c2..8de62d76c663 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -494,6 +494,9 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, struct inet_connection_sock *newicsk; struct tcp_sock *oldtp, *newtp; u32 seq; +#ifdef CONFIG_TCP_AO + struct tcp_ao_key *ao_key; +#endif if (!newsk) return NULL; @@ -572,6 +575,13 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, if (treq->af_specific->req_md5_lookup(sk, req_to_sk(req))) newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED; #endif +#ifdef CONFIG_TCP_AO + newtp->ao_info = NULL; + ao_key = treq->af_specific->ao_lookup(sk, req, + tcp_rsk(req)->ao_keyid, -1); + if (ao_key) + newtp->tcp_header_len += tcp_ao_len(ao_key); + #endif if (skb->len >= TCP_MSS_DEFAULT + newtp->tcp_header_len) newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len; newtp->rx_opt.mss_clamp = req->mss; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 3aea90605034..758c4a6e851b 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -606,6 +606,7 @@ static void bpf_skops_write_hdr_opt(struct sock *sk, struct sk_buff *skb, * (but it may well be that other scenarios fail similarly). */ static void tcp_options_write(struct tcphdr *th, struct tcp_sock *tp, + const struct tcp_request_sock *tcprsk, struct tcp_out_options *opts, struct tcp_ao_key *ao_key) { @@ -620,19 +621,32 @@ static void tcp_options_write(struct tcphdr *th, struct tcp_sock *tp, ptr += 4; } #ifdef CONFIG_TCP_AO - if (unlikely(OPTION_AO & options) && tp) { - struct tcp_ao_info *ao_info; + if (unlikely(OPTION_AO & options)) { u8 maclen; - ao_info = rcu_dereference_check(tp->ao_info, + if (tp) { + struct tcp_ao_info *ao_info; + + ao_info = rcu_dereference_check(tp->ao_info, lockdep_sock_is_held(&tp->inet_conn.icsk_inet.sk)); - if (WARN_ON_ONCE(!ao_key || !ao_info || !ao_info->rnext_key)) + if (WARN_ON_ONCE(!ao_key || !ao_info || !ao_info->rnext_key)) + goto out_ao; + maclen = tcp_ao_maclen(ao_key); + *ptr++ = htonl((TCPOPT_AO << 24) | + (tcp_ao_len(ao_key) << 16) | + (ao_key->sndid << 8) | + (ao_info->rnext_key->rcvid)); + } else if (tcprsk) { + u8 aolen = tcprsk->maclen + sizeof(struct tcp_ao_hdr); + + maclen = tcprsk->maclen; + *ptr++ = htonl((TCPOPT_AO << 24) | (aolen << 16) | + (tcprsk->ao_keyid << 8) | + (tcprsk->ao_rcv_next)); + } else { + WARN_ON_ONCE(1); goto out_ao; - maclen = tcp_ao_maclen(ao_key); - *ptr++ = htonl((TCPOPT_AO << 24) | - (tcp_ao_len(ao_key) << 16) | - (ao_key->sndid << 8) | - (ao_info->rnext_key->rcvid)); + } opts->hash_location = (__u8 *)ptr; ptr += maclen / sizeof(*ptr); if (unlikely(maclen % sizeof(*ptr))) { @@ -1411,7 +1425,7 @@ static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, th->window = htons(min(tp->rcv_wnd, 65535U)); } - tcp_options_write(th, tp, &opts, ao_key); + tcp_options_write(th, tp, NULL, &opts, ao_key); #ifdef CONFIG_TCP_MD5SIG /* Calculate the MD5 hash, as we have all we need now */ @@ -3702,7 +3716,7 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rsk_rcv_wnd, 65535U)); - tcp_options_write(th, NULL, &opts, NULL); + tcp_options_write(th, NULL, NULL, &opts, NULL); th->doff = (tcp_header_size >> 2); __TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTSEGS); diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 5014aa663452..ad7a8caa7b2a 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -214,6 +214,8 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) treq->snt_isn = cookie; treq->ts_off = 0; treq->txhash = net_tx_rndhash(); + tcp_ao_syncookie(sk, skb, treq, AF_INET6); + if (IS_ENABLED(CONFIG_SMC)) ireq->smc_ok = 0; diff --git a/net/ipv6/tcp_ao.c b/net/ipv6/tcp_ao.c index 7fd31c60488a..31ae504af8e6 100644 --- a/net/ipv6/tcp_ao.c +++ b/net/ipv6/tcp_ao.c @@ -53,6 +53,18 @@ int tcp_v6_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, htons(sk->sk_num), disn, sisn); } +int tcp_v6_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, + struct request_sock *req) +{ + struct inet_request_sock *ireq = inet_rsk(req); + + return tcp_v6_ao_calc_key(mkt, key, + &ireq->ir_v6_loc_addr, &ireq->ir_v6_rmt_addr, + htons(ireq->ir_num), ireq->ir_rmt_port, + htonl(tcp_rsk(req)->snt_isn), + htonl(tcp_rsk(req)->rcv_isn)); +} + struct tcp_ao_key *tcp_v6_ao_do_lookup(const struct sock *sk, const struct in6_addr *addr, int sndid, int rcvid) @@ -70,6 +82,15 @@ struct tcp_ao_key *tcp_v6_ao_lookup(const struct sock *sk, return tcp_v6_ao_do_lookup(sk, addr, sndid, rcvid); } +struct tcp_ao_key *tcp_v6_ao_lookup_rsk(const struct sock *sk, + struct request_sock *req, + int sndid, int rcvid) +{ + struct in6_addr *addr = &inet_rsk(req)->ir_v6_rmt_addr; + + return tcp_v6_ao_do_lookup(sk, addr, sndid, rcvid); +} + int tcp_v6_ao_hash_pseudoheader(struct crypto_pool_ahash *hp, const struct in6_addr *daddr, const struct in6_addr *saddr, int nbytes) diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 7bd4d0bb77cd..88a8e6ce41dc 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -853,6 +853,10 @@ const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { .req_md5_lookup = tcp_v6_md5_lookup, .calc_md5_hash = tcp_v6_md5_hash_skb, #endif +#ifdef CONFIG_TCP_AO + .ao_lookup = tcp_v6_ao_lookup_rsk, + .ao_calc_key = tcp_v6_ao_calc_key_rsk, +#endif #ifdef CONFIG_SYN_COOKIES .cookie_init_seq = cookie_v6_init_sequence, #endif @@ -1237,9 +1241,51 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, struct request_sock *req) { + struct tcp_md5sig_key *md5_key = NULL; + struct tcp_ao_key *ao_key = NULL; + const struct in6_addr *addr; + u8 keyid = 0; +#ifdef CONFIG_TCP_AO + char traffic_key[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + const struct tcp_ao_hdr *aoh; +#else + u8 *traffic_key = NULL; +#endif int l3index; l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0; + addr = &ipv6_hdr(skb)->saddr; + + if (tcp_rsk_used_ao(req)) { +#ifdef CONFIG_TCP_AO + /* Invalid TCP option size or twice included auth */ + if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh)) + return; + if (!aoh) + return; + ao_key = tcp_v6_ao_do_lookup(sk, addr, aoh->rnext_keyid, -1); + if (unlikely(!ao_key)) { + /* Send ACK with any matching MKT for the peer */ + ao_key = tcp_v6_ao_do_lookup(sk, addr, -1, -1); + /* Matching key disappeared (user removed the key?) + * let the handshake timeout. + */ + if (!ao_key) { + net_info_ratelimited("TCP-AO key for (%pI6, %d)->(%pI6, %d) suddenly disappeared, won't ACK new connection\n", + addr, + ntohs(tcp_hdr(skb)->source), + &ipv6_hdr(skb)->daddr, + ntohs(tcp_hdr(skb)->dest)); + return; + } + } + + keyid = aoh->keyid; + tcp_v6_ao_calc_key_rsk(ao_key, traffic_key, req); +#endif + } else { + md5_key = tcp_v6_md5_do_lookup(sk, addr, l3index); + } /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV * sk->sk_state == TCP_SYN_RECV -> for Fast Open. @@ -1255,9 +1301,9 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, req->ts_recent, sk->sk_bound_dev_if, - tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr, l3index), + md5_key, ipv6_get_dsfield(ipv6_hdr(skb)), 0, sk->sk_priority, - tcp_rsk(req)->txhash, NULL, NULL, 0, 0); + tcp_rsk(req)->txhash, ao_key, traffic_key, keyid, 0); } @@ -1487,18 +1533,26 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * #ifdef CONFIG_TCP_MD5SIG l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif); - /* Copy over the MD5 key from the original socket */ - key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr, l3index); - if (key) { - /* We're using one, so create a matching key - * on the newsk structure. If we fail to get - * memory, then we end up not copying the key - * across. Shucks. - */ - tcp_md5_key_copy(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, - AF_INET6, 128, l3index, key); + if (!tcp_rsk_used_ao(req)) { + const struct in6_addr *daddr = &newsk->sk_v6_daddr; + /* Copy over the MD5 key from the original socket */ + key = tcp_v6_md5_do_lookup(sk, daddr, l3index); + if (key) { + /* We're using one, so create a matching key + * on the newsk structure. If we fail to get + * memory, then we end up not copying the key + * across. Shucks. + */ + tcp_md5_key_copy(newsk, (union tcp_md5_addr *)daddr, + AF_INET6, 128, l3index, key); + } } #endif +#ifdef CONFIG_TCP_AO + /* Copy over tcp_ao_info if any */ + if (tcp_ao_copy_all_matching(sk, newsk, req, skb, AF_INET6)) + goto out; /* OOM */ +#endif if (__inet_inherit_port(sk, newsk) < 0) { inet_csk_prepare_forced_close(newsk); -- 2.38.1