From 06b22ef29591f625ef877ae00d82192938e29e60 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov Date: Mon, 23 Oct 2023 20:22:02 +0100 Subject: net/tcp: Wire TCP-AO to request sockets 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 Signed-off-by: Francesco Ruggeri Co-developed-by: Salam Noureddine Signed-off-by: Salam Noureddine Signed-off-by: Dmitry Safonov Acked-by: David Ahern Signed-off-by: David S. Miller --- include/linux/tcp.h | 18 ++++ include/net/tcp.h | 6 ++ include/net/tcp_ao.h | 24 +++++ net/ipv4/syncookies.c | 2 + net/ipv4/tcp_ao.c | 264 ++++++++++++++++++++++++++++++++++++++++++++--- net/ipv4/tcp_input.c | 15 +++ net/ipv4/tcp_ipv4.c | 66 ++++++++++-- net/ipv4/tcp_minisocks.c | 10 ++ net/ipv4/tcp_output.c | 37 ++++--- net/ipv6/syncookies.c | 2 + net/ipv6/tcp_ao.c | 38 ++++++- net/ipv6/tcp_ipv6.c | 75 +++++++++++--- 12 files changed, 506 insertions(+), 51 deletions(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index eec6e7e5312e..ec4e9367f5b0 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -166,6 +166,11 @@ 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) @@ -173,6 +178,19 @@ 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 +} + #define TCP_RMEM_TO_WIN_SCALE 8 struct tcp_sock { diff --git a/include/net/tcp.h b/include/net/tcp.h index 17b3ecd2760f..d0bea102b523 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2216,6 +2216,12 @@ 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 971d7edcda9c..d2c1ee8bf7b0 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -123,6 +123,9 @@ int tcp_parse_ao(struct sock *sk, int cmd, unsigned short int family, sockptr_t optval, int optlen); struct tcp_ao_key *tcp_ao_established_key(struct tcp_ao_info *ao, int sndid, int rcvid); +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, struct tcp_sigpool *hp); void tcp_ao_destroy_sock(struct sock *sk, bool twsk); @@ -147,6 +150,11 @@ 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); @@ -154,11 +162,21 @@ int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key, int tcp_v6_ao_hash_pseudoheader(struct tcp_sigpool *hp, const struct in6_addr *daddr, const struct in6_addr *saddr, int nbytes); +int tcp_v6_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key, + const struct sk_buff *skb, __be32 sisn, __be32 disn); 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); @@ -178,6 +196,12 @@ static inline int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb, return 0; } +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) { diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index c64334363230..0681d3e82b11 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -400,6 +400,8 @@ 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 7c4e2f42845a..68d81704e14e 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -169,6 +169,23 @@ 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); + tcp_sigpool_get(new_key->tcp_sigpool_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); @@ -290,6 +307,42 @@ static int tcp_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, return -EOPNOTSUPP; } +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_calc_key_skb(struct tcp_ao_key *mkt, u8 *key, + const struct sk_buff *skb, + __be32 sisn, __be32 disn) +{ + const struct iphdr *iph = ip_hdr(skb); + const struct tcphdr *th = tcp_hdr(skb); + + return tcp_v4_ao_calc_key(mkt, key, iph->saddr, iph->daddr, + th->source, th->dest, sisn, disn); +} + +static int tcp_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key, + const struct sk_buff *skb, + __be32 sisn, __be32 disn, int family) +{ + if (family == AF_INET) + return tcp_v4_ao_calc_key_skb(mkt, key, skb, sisn, disn); +#if IS_ENABLED(CONFIG_IPV6) + else if (family == AF_INET6) + return tcp_v6_ao_calc_key_skb(mkt, key, skb, sisn, disn); +#endif + return -EAFNOSUPPORT; +} + static int tcp_v4_ao_hash_pseudoheader(struct tcp_sigpool *hp, __be32 daddr, __be32 saddr, int nbytes) @@ -515,6 +568,16 @@ 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); +} + struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, int sndid, int rcvid) { @@ -528,7 +591,7 @@ int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb, struct tcp_ao_key **key, char **traffic_key, bool *allocated_traffic_key, u8 *keyid, u32 *sne) { - struct tcp_ao_key *rnext_key; + const struct tcphdr *th = tcp_hdr(skb); struct tcp_ao_info *ao_info; *allocated_traffic_key = false; @@ -543,23 +606,62 @@ int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb, return -ENOTCONN; if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV)) { - return -1; + unsigned int family = READ_ONCE(sk->sk_family); + union tcp_ao_addr *addr; + __be32 disn, sisn; - if (sk->sk_state == TCP_TIME_WAIT) - ao_info = rcu_dereference(tcp_twsk(sk)->ao_info); - else + if (sk->sk_state == TCP_NEW_SYN_RECV) { + struct request_sock *req = inet_reqsk(sk); + + sisn = htonl(tcp_rsk(req)->rcv_isn); + disn = htonl(tcp_rsk(req)->snt_isn); + *sne = 0; + } else { + sisn = th->seq; + disn = 0; + } + if (IS_ENABLED(CONFIG_IPV6) && family == AF_INET6) + addr = (union tcp_md5_addr *)&ipv6_hdr(skb)->saddr; + else + addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; +#if IS_ENABLED(CONFIG_IPV6) + if (family == AF_INET6 && ipv6_addr_v4mapped(&sk->sk_v6_daddr)) + family = AF_INET; +#endif + + sk = sk_const_to_full_sk(sk); ao_info = rcu_dereference(tcp_sk(sk)->ao_info); - if (!ao_info) - return -ENOENT; + if (!ao_info) + return -ENOENT; + *key = tcp_ao_do_lookup(sk, addr, family, -1, aoh->rnext_keyid); + if (!*key) + return -ENOENT; + *traffic_key = kmalloc(tcp_ao_digest_size(*key), GFP_ATOMIC); + if (!*traffic_key) + return -ENOMEM; + *allocated_traffic_key = true; + if (tcp_ao_calc_key_skb(*key, *traffic_key, skb, + sisn, disn, family)) + return -1; + *keyid = (*key)->rcvid; + } else { + struct tcp_ao_key *rnext_key; - *key = tcp_ao_established_key(ao_info, aoh->rnext_keyid, -1); - if (!*key) - return -ENOENT; - *traffic_key = snd_other_key(*key); - rnext_key = READ_ONCE(ao_info->rnext_key); - *keyid = rnext_key->rcvid; - *sne = 0; + if (sk->sk_state == TCP_TIME_WAIT) + ao_info = rcu_dereference(tcp_twsk(sk)->ao_info); + else + ao_info = rcu_dereference(tcp_sk(sk)->ao_info); + if (!ao_info) + return -ENOENT; + *key = tcp_ao_established_key(ao_info, aoh->rnext_keyid, -1); + if (!*key) + return -ENOENT; + *traffic_key = snd_other_key(*key); + rnext_key = READ_ONCE(ao_info->rnext_key); + *keyid = rnext_key->rcvid; + *sne = 0; + } return 0; } @@ -597,6 +699,46 @@ int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb, return 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_ao_addr *)&iph->saddr, + AF_INET, sndid, rcvid); + } else { + const struct ipv6hdr *iph = ipv6_hdr(skb); + + return tcp_ao_do_lookup(sk, (union tcp_ao_addr *)&iph->saddr, + AF_INET6, sndid, rcvid); + } +} + +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; + + if (tcp_parse_auth_options(th, NULL, &aoh) || !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); +} + static int tcp_ao_cache_traffic_keys(const struct sock *sk, struct tcp_ao_info *ao, struct tcp_ao_key *ao_key) @@ -704,6 +846,100 @@ void tcp_ao_finish_connect(struct sock *sk, struct sk_buff *skb) tcp_ao_cache_traffic_keys(sk, ao, key); } +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_key *key, *new_key, *first_key; + struct tcp_ao_info *new_ao, *ao; + struct hlist_node *key_head; + union tcp_ao_addr *addr; + bool match = false; + int ret = -ENOMEM; + + 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); + if (!new_ao) + return -ENOMEM; + new_ao->lisn = htonl(tcp_rsk(req)->snt_isn); + new_ao->risn = htonl(tcp_rsk(req)->rcv_isn); + new_ao->ao_required = ao->ao_required; + + 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 { + ret = -EAFNOSUPPORT; + goto free_ao; + } + + hlist_for_each_entry_rcu(key, &ao->head, node) { + if (tcp_ao_key_cmp(key, addr, key->prefixlen, family, -1, -1)) + 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) { + /* RFC5925 (7.4.1) specifies that the TCP-AO status + * of a connection is determined on the initial SYN. + * At this point the connection was TCP-AO enabled, so + * it can't switch to being unsigned if peer's key + * disappears on the listening socket. + */ + ret = -EKEYREJECTED; + goto free_and_exit; + } + + key_head = rcu_dereference(hlist_first_rcu(&new_ao->head)); + first_key = hlist_entry_safe(key_head, struct tcp_ao_key, node); + + key = tcp_ao_established_key(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_established_key(new_ao, -1, tcp_rsk(req)->ao_rcv_next); + if (key) + new_ao->rnext_key = key; + else + new_ao->rnext_key = first_key; + + 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, key_head, &new_ao->head, node) { + hlist_del(&key->node); + tcp_sigpool_release(key->tcp_sigpool_id); + atomic_sub(tcp_ao_sizeof_key(key), &newsk->sk_omem_alloc); + kfree_sensitive(key); + } +free_ao: + kfree(new_ao); + return ret; +} + static bool tcp_ao_can_set_current_rnext(struct sock *sk) { /* There aren't current/rnext keys on TCP_LISTEN sockets */ diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index fc42b172abf6..de64c0c2fb69 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -7045,6 +7045,10 @@ 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 @@ -7131,6 +7135,17 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, inet_rsk(req)->ecn_ok = 0; } +#ifdef CONFIG_TCP_AO + 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 a78112d78d06..2bd56b57f3c9 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1072,13 +1072,47 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt; - /* RFC 7323 2.3 - * The window field (SEG.WND) of every outgoing segment, with the - * exception of segments, MUST be right-shifted by - * Rcv.Wind.Shift bits: - */ +#ifdef CONFIG_TCP_AO + if (tcp_rsk_used_ao(req)) { + const union tcp_md5_addr *addr; + const struct tcp_ao_hdr *aoh; + + /* Invalid TCP option size or twice included auth */ + if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh)) + return; + if (!aoh) + return; + + addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; + key.ao_key = tcp_ao_do_lookup(sk, addr, AF_INET, + aoh->rnext_keyid, -1); + if (unlikely(!key.ao_key)) { + /* Send ACK with any matching MKT for the peer */ + key.ao_key = tcp_ao_do_lookup(sk, addr, AF_INET, -1, -1); + /* Matching key disappeared (user removed the key?) + * let the handshake timeout. + */ + if (!key.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; + } + } + key.traffic_key = kmalloc(tcp_ao_digest_size(key.ao_key), GFP_ATOMIC); + if (!key.traffic_key) + return; + + key.type = TCP_KEY_AO; + key.rcv_next = aoh->keyid; + tcp_v4_ao_calc_key_rsk(key.ao_key, key.traffic_key, req); +#else + if (0) { +#endif #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed.key)) { + } else if (static_branch_unlikely(&tcp_md5_needed.key)) { const union tcp_md5_addr *addr; int l3index; @@ -1087,8 +1121,14 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, key.md5_key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); if (key.md5_key) key.type = TCP_KEY_MD5; - } #endif + } + + /* RFC 7323 2.3 + * The window field (SEG.WND) of every outgoing segment, with the + * exception of segments, MUST be right-shifted by + * Rcv.Wind.Shift bits: + */ tcp_v4_send_ack(sk, skb, seq, tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, @@ -1098,6 +1138,8 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, ip_hdr(skb)->tos, READ_ONCE(tcp_rsk(req)->txhash)); + if (tcp_key_is_ao(&key)) + kfree(key.traffic_key); } /* @@ -1636,6 +1678,10 @@ 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 @@ -1737,12 +1783,16 @@ 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)) { if (tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key)) goto put_and_exit; 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 6810cf65a322..8d941a6e066b 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -506,6 +506,9 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, const struct tcp_sock *oldtp; struct tcp_sock *newtp; u32 seq; +#ifdef CONFIG_TCP_AO + struct tcp_ao_key *ao_key; +#endif if (!newsk) return NULL; @@ -594,6 +597,13 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, #ifdef CONFIG_TCP_MD5SIG newtp->md5sig_info = NULL; /*XXX*/ #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 de546313a214..d44ef88025fb 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -615,6 +615,7 @@ 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_key *key) { @@ -629,20 +630,28 @@ static void tcp_options_write(struct tcphdr *th, struct tcp_sock *tp, ptr += 4; } else if (tcp_key_is_ao(key)) { #ifdef CONFIG_TCP_AO - struct tcp_ao_key *rnext_key; - struct tcp_ao_info *ao_info; - u8 maclen; + u8 maclen = tcp_ao_maclen(key->ao_key); - ao_info = rcu_dereference_check(tp->ao_info, + if (tcprsk) { + u8 aolen = maclen + sizeof(struct tcp_ao_hdr); + + *ptr++ = htonl((TCPOPT_AO << 24) | (aolen << 16) | + (tcprsk->ao_keyid << 8) | + (tcprsk->ao_rcv_next)); + } else { + struct tcp_ao_key *rnext_key; + struct tcp_ao_info *ao_info; + + ao_info = rcu_dereference_check(tp->ao_info, lockdep_sock_is_held(&tp->inet_conn.icsk_inet.sk)); - rnext_key = READ_ONCE(ao_info->rnext_key); - if (WARN_ON_ONCE(!rnext_key)) - goto out_ao; - maclen = tcp_ao_maclen(key->ao_key); - *ptr++ = htonl((TCPOPT_AO << 24) | - (tcp_ao_len(key->ao_key) << 16) | - (key->ao_key->sndid << 8) | - (rnext_key->rcvid)); + rnext_key = READ_ONCE(ao_info->rnext_key); + if (WARN_ON_ONCE(!rnext_key)) + goto out_ao; + *ptr++ = htonl((TCPOPT_AO << 24) | + (tcp_ao_len(key->ao_key) << 16) | + (key->ao_key->sndid << 8) | + (rnext_key->rcvid)); + } opts->hash_location = (__u8 *)ptr; ptr += maclen / sizeof(*ptr); if (unlikely(maclen % sizeof(*ptr))) { @@ -1386,7 +1395,7 @@ 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, &key); + tcp_options_write(th, tp, NULL, &opts, &key); if (tcp_key_is_md5(&key)) { #ifdef CONFIG_TCP_MD5SIG @@ -3729,7 +3738,7 @@ 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, &key); + tcp_options_write(th, NULL, NULL, &opts, &key); 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 d08735b6f3c5..c9a6fa84f6ce 100644 --- a/net/ipv6/tcp_ao.c +++ b/net/ipv6/tcp_ao.c @@ -49,6 +49,17 @@ static int tcp_v6_ao_calc_key(struct tcp_ao_key *mkt, u8 *key, return err; } +int tcp_v6_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key, + const struct sk_buff *skb, + __be32 sisn, __be32 disn) +{ + const struct ipv6hdr *iph = ipv6_hdr(skb); + const struct tcphdr *th = tcp_hdr(skb); + + return tcp_v6_ao_calc_key(mkt, key, &iph->saddr, &iph->daddr, + th->source, th->dest, sisn, disn); +} + int tcp_v6_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, const struct sock *sk, __be32 sisn, __be32 disn, bool send) @@ -63,9 +74,21 @@ int tcp_v6_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, htons(sk->sk_num), disn, sisn); } -static struct tcp_ao_key *tcp_v6_ao_do_lookup(const struct sock *sk, - const struct in6_addr *addr, - int sndid, int rcvid) +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) { return tcp_ao_do_lookup(sk, (union tcp_ao_addr *)addr, AF_INET6, sndid, rcvid); @@ -80,6 +103,15 @@ 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 tcp_sigpool *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 e6c3617976f0..b08b177847da 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -836,6 +836,10 @@ 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 @@ -1192,16 +1196,54 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, { struct tcp_key key = {}; +#ifdef CONFIG_TCP_AO + if (tcp_rsk_used_ao(req)) { + const struct in6_addr *addr = &ipv6_hdr(skb)->saddr; + const struct tcp_ao_hdr *aoh; + int l3index; + + l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0; + /* Invalid TCP option size or twice included auth */ + if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh)) + return; + if (!aoh) + return; + key.ao_key = tcp_v6_ao_do_lookup(sk, addr, aoh->rnext_keyid, -1); + if (unlikely(!key.ao_key)) { + /* Send ACK with any matching MKT for the peer */ + key.ao_key = tcp_v6_ao_do_lookup(sk, addr, -1, -1); + /* Matching key disappeared (user removed the key?) + * let the handshake timeout. + */ + if (!key.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; + } + } + key.traffic_key = kmalloc(tcp_ao_digest_size(key.ao_key), GFP_ATOMIC); + if (!key.traffic_key) + return; + + key.type = TCP_KEY_AO; + key.rcv_next = aoh->keyid; + tcp_v6_ao_calc_key_rsk(key.ao_key, key.traffic_key, req); +#else + if (0) { +#endif #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed.key)) { + } else if (static_branch_unlikely(&tcp_md5_needed.key)) { int l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0; key.md5_key = tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr, l3index); if (key.md5_key) key.type = TCP_KEY_MD5; - } #endif + } /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV * sk->sk_state == TCP_SYN_RECV -> for Fast Open. @@ -1220,6 +1262,8 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, &key, ipv6_get_dsfield(ipv6_hdr(skb)), 0, READ_ONCE(sk->sk_priority), READ_ONCE(tcp_rsk(req)->txhash)); + if (tcp_key_is_ao(&key)) + kfree(key.traffic_key); } @@ -1449,19 +1493,26 @@ 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) { - const union tcp_md5_addr *addr; - - addr = (union tcp_md5_addr *)&newsk->sk_v6_daddr; - if (tcp_md5_key_copy(newsk, addr, AF_INET6, 128, l3index, key)) { - inet_csk_prepare_forced_close(newsk); - tcp_done(newsk); - goto out; + if (!tcp_rsk_used_ao(req)) { + /* Copy over the MD5 key from the original socket */ + key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr, l3index); + if (key) { + const union tcp_md5_addr *addr; + + addr = (union tcp_md5_addr *)&newsk->sk_v6_daddr; + if (tcp_md5_key_copy(newsk, addr, AF_INET6, 128, l3index, key)) { + inet_csk_prepare_forced_close(newsk); + tcp_done(newsk); + goto out; + } } } #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); -- cgit v1.2.3