Wire up sending resets to TCP-AO hashing. 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/net/tcp_ao.h | 7 ++++ net/ipv4/tcp_ao.c | 48 +++++++++++++++++++++++++++ net/ipv4/tcp_ipv4.c | 48 ++++++++++++++++++++++++++- net/ipv6/tcp_ipv6.c | 77 ++++++++++++++++++++++++++++++++++++++++++-- 4 files changed, 176 insertions(+), 4 deletions(-) diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index b5516c83e489..35c33f7e9c27 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -117,6 +117,7 @@ int tcp_ao_hash_skb(unsigned short int family, const u8 *tkey, int hash_offset, u32 sne); 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_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx, unsigned int len); void tcp_ao_destroy_sock(struct sock *sk); @@ -126,6 +127,12 @@ int tcp_ao_cache_traffic_keys(const struct sock *sk, struct tcp_ao_info *ao, 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); +int tcp_ao_hash_hdr(unsigned short family, char *ao_hash, + struct tcp_ao_key *key, const u8 *tkey, + const union tcp_ao_addr *daddr, + const union tcp_ao_addr *saddr, + const struct tcphdr *th, u32 sne); + /* ipv4 specific functions */ int tcp_v4_parse_ao(struct sock *sk, int optname, sockptr_t optval, int optlen); struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk, diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index ec3ab0c3dc77..4bdd97536610 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -409,6 +409,54 @@ static int tcp_ao_hash_skb_data(struct crypto_pool_ahash *hp, return 0; } +int tcp_ao_hash_hdr(unsigned short int family, char *ao_hash, + struct tcp_ao_key *key, const u8 *tkey, + const union tcp_ao_addr *daddr, + const union tcp_ao_addr *saddr, + const struct tcphdr *th, u32 sne) +{ + struct crypto_pool_ahash hp; + int tkey_len = tcp_ao_digest_size(key); + int hash_offset = ao_hash - (char *)th; + + if (crypto_pool_get(key->crypto_pool_id, (struct crypto_pool *)&hp)) + goto clear_hash_noput; + + if (crypto_ahash_setkey(crypto_ahash_reqtfm(hp.req), tkey, tkey_len)) + goto clear_hash; + + if (crypto_ahash_init(hp.req)) + goto clear_hash; + + if (tcp_ao_hash_sne(&hp, sne)) + goto clear_hash; + if (family == AF_INET) { + if (tcp_v4_ao_hash_pseudoheader(&hp, daddr->a4.s_addr, + saddr->a4.s_addr, th->doff * 4)) + goto clear_hash; + } else if (family == AF_INET6) { + if (tcp_v6_ao_hash_pseudoheader(&hp, &daddr->a6, + &saddr->a6, th->doff * 4)) + goto clear_hash; + } + if (tcp_ao_hash_header(&hp, th, false, + ao_hash, hash_offset, tcp_ao_maclen(key))) + goto clear_hash; + ahash_request_set_crypt(hp.req, NULL, ao_hash, 0); + if (crypto_ahash_final(hp.req)) + goto clear_hash; + + crypto_pool_put(); + return 0; + +clear_hash: + crypto_pool_put(); +clear_hash_noput: + memset(ao_hash, 0, tcp_ao_maclen(key)); + return 1; +} +EXPORT_SYMBOL(tcp_ao_hash_hdr); + int tcp_ao_hash_skb(unsigned short int family, char *ao_hash, struct tcp_ao_key *key, const struct sock *sk, const struct sk_buff *skb, diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 034549c73beb..c0add782d7af 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -679,11 +679,17 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) #ifdef CONFIG_TCP_MD5SIG struct tcp_md5sig_key *key = NULL; const __u8 *md5_hash_location = NULL; + const struct tcp_ao_hdr *aoh; unsigned char newhash[16]; int genhash; struct sock *sk1 = NULL; #endif u64 transmit_time = 0; +#ifdef CONFIG_TCP_AO + struct tcp_ao_key *ao_key = NULL; + char traffic_key[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + u32 ao_sne; +#endif struct sock *ctl_sk; struct net *net; @@ -719,7 +725,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); #if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO) /* Invalid TCP option size or twice included auth */ - if (tcp_parse_auth_options(tcp_hdr(skb), &md5_hash_location, NULL)) + if (tcp_parse_auth_options(tcp_hdr(skb), &md5_hash_location, &aoh)) return; rcu_read_lock(); @@ -785,6 +791,46 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) key, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, &rep.th); } +#endif +#ifdef CONFIG_TCP_AO + if (sk && aoh && sk->sk_state != TCP_LISTEN) { + /* lookup key based on peer address and rcv_next*/ + ao_key = tcp_ao_do_lookup_sndid(sk, aoh->rnext_keyid); + + if (ao_key) { + struct tcp_ao_info *ao_info; + u8 keyid; + + ao_info = rcu_dereference(tcp_sk(sk)->ao_info); + + /* XXX: optimize by using cached traffic key depending + * on socket state + */ + tcp_v4_ao_calc_key_sk(ao_key, traffic_key, sk, + ao_info->lisn, ao_info->risn, + true); + + /* rcv_next holds the rcv_next of the peer, make keyid + * hold our rcv_next + */ + keyid = ao_info->rnext_key->rcvid; + ao_sne = tcp_ao_compute_sne(ao_info->snd_sne, + ao_info->snd_sne_seq, + ntohl(rep.th.seq)); + + rep.opt[0] = htonl((TCPOPT_AO << 24) | + (tcp_ao_len(ao_key) << 16) | + (aoh->rnext_keyid << 8) | keyid); + arg.iov[0].iov_len += round_up(tcp_ao_len(ao_key), 4); + rep.th.doff = arg.iov[0].iov_len / 4; + + tcp_ao_hash_hdr(AF_INET, (char *)&rep.opt[1], + ao_key, traffic_key, + (union tcp_ao_addr *)&ip_hdr(skb)->saddr, + (union tcp_ao_addr *)&ip_hdr(skb)->daddr, + &rep.th, ao_sne); + } + } #endif /* Can't co-exist with TCPMD5, hence check rep.opt[0] */ if (rep.opt[0] == 0) { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index ba968e856ca9..f5d339d5291a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -847,7 +847,9 @@ const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, struct tcp_md5sig_key *key, int rst, - u8 tclass, __be32 label, u32 priority) + u8 tclass, __be32 label, u32 priority, + struct tcp_ao_key *ao_key, char *tkey, + u8 rcv_next, u32 ao_sne) { const struct tcphdr *th = tcp_hdr(skb); struct tcphdr *t1; @@ -866,6 +868,13 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 if (key) tot_len += TCPOLEN_MD5SIG_ALIGNED; #endif +#ifdef CONFIG_TCP_AO + if (ao_key) + tot_len += tcp_ao_len(ao_key); +#endif +#if defined(CONFIG_TCP_MD5SIG) && defined(CONFIG_TCP_AO) + WARN_ON_ONCE(key && ao_key); +#endif #ifdef CONFIG_MPTCP if (rst && !key) { @@ -917,6 +926,21 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 &ipv6_hdr(skb)->daddr, t1); } #endif +#ifdef CONFIG_TCP_AO + if (ao_key) { + *topt++ = htonl((TCPOPT_AO << 24) | (tcp_ao_len(ao_key) << 16) | + (ao_key->sndid << 8) | (rcv_next)); + + /* TODO: this is right now not going to work for listening + * sockets since the socket won't have the needed ipv6 + * addresses + */ + tcp_ao_hash_hdr(AF_INET6, (char *)topt, ao_key, tkey, + (union tcp_ao_addr *)&ipv6_hdr(skb)->saddr, + (union tcp_ao_addr *)&ipv6_hdr(skb)->daddr, + t1, ao_sne); + } +#endif memset(&fl6, 0, sizeof(fl6)); fl6.daddr = ipv6_hdr(skb)->saddr; @@ -990,6 +1014,15 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) __be32 label = 0; u32 priority = 0; struct net *net; + struct tcp_ao_key *ao_key = NULL; + u8 rcv_next = 0; + u32 ao_sne = 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 oif = 0; if (th->rst) @@ -1004,8 +1037,13 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); #if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO) /* Invalid TCP option size or twice included auth */ +#if defined(CONFIG_TCP_AO) + if (tcp_parse_auth_options(th, &md5_hash_location, &aoh)) + return; +#else if (tcp_parse_auth_options(th, &md5_hash_location, NULL)) return; +#endif rcu_read_lock(); #endif @@ -1059,6 +1097,38 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - (th->doff << 2); +#ifdef CONFIG_TCP_AO + /* XXX: Not implemented for listening sockets yet. How do we + * get the initial sequence numbers? Might need to pass in + * the request socket. + */ + if (sk && aoh && sk->sk_state != TCP_LISTEN) { + struct tcp_ao_info *ao_info; + + if (WARN_ON_ONCE(sk->sk_state == TCP_NEW_SYN_RECV)) + goto out; + + /* rcv_next is the peer's here */ + ao_key = tcp_ao_do_lookup_sndid(sk, aoh->rnext_keyid); + + if (ao_key) { + ao_info = rcu_dereference(tcp_sk(sk)->ao_info); + + /* XXX: optimize by using cached traffic key depending + * on socket state + */ + tcp_v6_ao_calc_key_sk(ao_key, traffic_key, sk, + ao_info->lisn, ao_info->risn, + true); + + /* rcv_next switches to our rcv_next */ + rcv_next = ao_info->rnext_key->rcvid; + ao_sne = tcp_ao_compute_sne(ao_info->snd_sne, + ao_info->snd_sne_seq, seq); + } + } +#endif + if (sk) { oif = sk->sk_bound_dev_if; if (sk_fullsock(sk)) { @@ -1079,7 +1149,8 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) } tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, - ipv6_get_dsfield(ipv6h), label, priority); + ipv6_get_dsfield(ipv6h), label, priority, + ao_key, traffic_key, rcv_next, ao_sne); #if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO) out: @@ -1093,7 +1164,7 @@ static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, __be32 label, u32 priority) { tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, - tclass, label, priority); + tclass, label, priority, NULL, NULL, 0, 0); } static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) -- 2.37.2