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Miller" Cc: Dmitry Safonov , Andy Lutomirski , Ard Biesheuvel , Bob Gilligan , Dan Carpenter , David Laight , Dmitry Safonov <0x7f454c46@gmail.com>, Eric Biggers , "Eric W. Biederman" , Francesco Ruggeri , Herbert Xu , Hideaki YOSHIFUJI , Ivan Delalande , Leonard Crestez , Salam Noureddine , netdev@vger.kernel.org, Francesco Ruggeri Subject: [PATCH v4 12/21] net/tcp: Verify inbound TCP-AO signed segments Date: Wed, 15 Feb 2023 18:33:26 +0000 Message-Id: <20230215183335.800122-13-dima@arista.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230215183335.800122-1-dima@arista.com> References: <20230215183335.800122-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1757923429533236999?= X-GMAIL-MSGID: =?utf-8?q?1757923429533236999?= Now there is a common function to verify signature on TCP segments: tcp_inbound_hash(). It has checks for all possible cross-interactions with MD5 signs as well as with unsigned segments. The rules from RFC5925 are: (1) Any TCP segment can have at max only one signature. (2) TCP connections can't switch between using TCP-MD5 and TCP-AO. (3) TCP-AO connections can't stop using AO, as well as unsigned connections can't suddenly start using AO. 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 --- include/net/dropreason.h | 18 +++++ include/net/tcp.h | 55 +++++++++++++- include/net/tcp_ao.h | 22 ++++++ net/ipv4/tcp.c | 39 ++-------- net/ipv4/tcp_ao.c | 154 +++++++++++++++++++++++++++++++++++++++ net/ipv4/tcp_ipv4.c | 10 +-- net/ipv6/tcp_ao.c | 12 +++ net/ipv6/tcp_ipv6.c | 11 +-- 8 files changed, 278 insertions(+), 43 deletions(-) diff --git a/include/net/dropreason.h b/include/net/dropreason.h index 70539288f995..848f4c5ab609 100644 --- a/include/net/dropreason.h +++ b/include/net/dropreason.h @@ -132,6 +132,11 @@ enum skb_drop_reason { * drop out of udp_memory_allocated. */ SKB_DROP_REASON_PROTO_MEM, + /** + * @SKB_DROP_REASON_TCP_AUTH_HDR: TCP-MD5 or TCP-AO hashes are met + * twice or set incorrectly. + */ + SKB_DROP_REASON_TCP_AUTH_HDR, /** * @SKB_DROP_REASON_TCP_MD5NOTFOUND: no MD5 hash and one expected, * corresponding to LINUX_MIB_TCPMD5NOTFOUND @@ -147,6 +152,19 @@ enum skb_drop_reason { * to LINUX_MIB_TCPMD5FAILURE */ SKB_DROP_REASON_TCP_MD5FAILURE, + /** + * @SKB_DROP_REASON_TCP_AONOTFOUND: no TCP-AO hash and one was expected + */ + SKB_DROP_REASON_TCP_AONOTFOUND, + /** + * @SKB_DROP_REASON_TCP_AOUNEXPECTED: TCP-AO hash is present and it + * was not expected. + */ + SKB_DROP_REASON_TCP_AOUNEXPECTED, + /** @SKB_DROP_REASON_TCP_AOKEYNOTFOUND: TCP-AO key is unknown */ + SKB_DROP_REASON_TCP_AOKEYNOTFOUND, + /** @SKB_DROP_REASON_TCP_AOFAILURE: TCP-AO hash is wrong */ + SKB_DROP_REASON_TCP_AOFAILURE, /** * @SKB_DROP_REASON_SOCKET_BACKLOG: failed to add skb to socket backlog ( * see LINUX_MIB_TCPBACKLOGDROP) diff --git a/include/net/tcp.h b/include/net/tcp.h index 1e5854a30e74..3825b1352014 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1732,7 +1732,7 @@ tcp_md5_do_lookup_any_l3index(const struct sock *sk, enum skb_drop_reason tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, const void *saddr, const void *daddr, - int family, int dif, int sdif); + int family, int l3index, const __u8 *hash_location); #define tcp_twsk_md5_key(twsk) ((twsk)->tw_md5_key) @@ -1754,7 +1754,7 @@ tcp_md5_do_lookup_any_l3index(const struct sock *sk, static inline enum skb_drop_reason tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, const void *saddr, const void *daddr, - int family, int dif, int sdif) + int family, int l3index, const __u8 *hash_location) { return SKB_NOT_DROPPED_YET; } @@ -2566,4 +2566,55 @@ static inline int tcp_parse_auth_options(const struct tcphdr *th, return 0; } +/* Called with rcu_read_lock() */ +static inline enum skb_drop_reason +tcp_inbound_hash(struct sock *sk, const struct request_sock *req, + const struct sk_buff *skb, + const void *saddr, const void *daddr, + int family, int dif, int sdif) +{ + const struct tcphdr *th = tcp_hdr(skb); + const struct tcp_ao_hdr *aoh; + const __u8 *md5_location; + int l3index; + + /* Invalid option or two times meet any of auth options */ + if (tcp_parse_auth_options(th, &md5_location, &aoh)) + return SKB_DROP_REASON_TCP_AUTH_HDR; + + if (req) { + if (tcp_rsk_used_ao(req) != !!aoh) + return SKB_DROP_REASON_TCP_AOFAILURE; + } + + /* sdif set, means packet ingressed via a device + * in an L3 domain and dif is set to the l3mdev + */ + l3index = sdif ? dif : 0; + + /* Fast path: unsigned segments */ + if (likely(!md5_location && !aoh)) { + /* Drop if there's TCP-MD5 or TCP-AO key with any rcvid/sndid + * for the remote peer. On TCP-AO established connection + * the last key is impossible to remove, so there's + * always at least one current_key. + */ +#ifdef CONFIG_TCP_AO + if (unlikely(tcp_ao_do_lookup(sk, saddr, family, -1, -1, 0))) + return SKB_DROP_REASON_TCP_AONOTFOUND; +#endif + if (unlikely(tcp_md5_do_lookup(sk, l3index, saddr, family))) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); + return SKB_DROP_REASON_TCP_MD5NOTFOUND; + } + return SKB_NOT_DROPPED_YET; + } + + if (aoh) + return tcp_inbound_ao_hash(sk, skb, family, req, aoh); + + return tcp_inbound_md5_hash(sk, skb, saddr, daddr, family, + l3index, md5_location); +} + #endif /* _TCP_H */ diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index 46b03e043d43..fbd4e2f6afff 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -109,6 +109,9 @@ struct tcp6_ao_context { __be32 disn; }; +#define TCP_AO_ESTABLISHED (TCPF_ESTABLISHED|TCPF_FIN_WAIT1|TCPF_FIN_WAIT2|\ + TCPF_CLOSE|TCPF_CLOSE_WAIT|TCPF_LAST_ACK|TCPF_CLOSING) + 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, @@ -127,6 +130,10 @@ u32 tcp_ao_compute_sne(u32 sne, u32 seq, u32 new_seq); void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp); int tcp_ao_cache_traffic_keys(const struct sock *sk, struct tcp_ao_info *ao, struct tcp_ao_key *ao_key); +enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk, + const struct sk_buff *skb, unsigned short int family, + const struct request_sock *req, + const struct tcp_ao_hdr *aoh); 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); @@ -148,9 +155,14 @@ int tcp_v4_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key, __be32 sisn, __be32 disn, bool send); int tcp_v4_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, struct request_sock *req); +int tcp_v4_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key, + const struct sk_buff *skb, __be32 sisn, __be32 disn); struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk, struct request_sock *req, int sndid, int rcvid); +bool tcp_v4_inbound_ao_hash(struct sock *sk, + struct request_sock *req, + const struct sk_buff *skb); 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); @@ -159,6 +171,9 @@ struct tcp_sigpool; 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); @@ -194,6 +209,13 @@ static inline void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, { } +static inline enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk, + const struct sk_buff *skb, unsigned short int family, + const struct request_sock *req, const struct tcp_ao_hdr *aoh) +{ + return SKB_NOT_DROPPED_YET; +} + 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/tcp.c b/net/ipv4/tcp.c index e4136e87a162..3a2caa5eeee2 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4517,42 +4517,23 @@ EXPORT_SYMBOL(tcp_md5_hash_key); enum skb_drop_reason tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, const void *saddr, const void *daddr, - int family, int dif, int sdif) + int family, int l3index, const __u8 *hash_location) { - /* - * This gets called for each TCP segment that arrives - * so we want to be efficient. + /* This gets called for each TCP segment that has TCP-MD5 option. * We have 3 drop cases: * o No MD5 hash and one expected. * o MD5 hash and we're not expecting one. * o MD5 hash and its wrong. */ - const __u8 *hash_location = NULL; - struct tcp_md5sig_key *hash_expected; const struct tcphdr *th = tcp_hdr(skb); struct tcp_sock *tp = tcp_sk(sk); - int genhash, l3index; + struct tcp_md5sig_key *key; + int genhash; u8 newhash[16]; - /* sdif set, means packet ingressed via a device - * in an L3 domain and dif is set to the l3mdev - */ - l3index = sdif ? dif : 0; - - hash_expected = tcp_md5_do_lookup(sk, l3index, saddr, family); - if (tcp_parse_auth_options(th, &hash_location, NULL)) - return true; - - /* We've parsed the options - do we have a hash? */ - if (!hash_expected && !hash_location) - return SKB_NOT_DROPPED_YET; - - if (hash_expected && !hash_location) { - NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); - return SKB_DROP_REASON_TCP_MD5NOTFOUND; - } + key = tcp_md5_do_lookup(sk, l3index, saddr, family); - if (!hash_expected && hash_location) { + if (!key && hash_location) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); return SKB_DROP_REASON_TCP_MD5UNEXPECTED; } @@ -4562,14 +4543,10 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, * IPv4-mapped case. */ if (family == AF_INET) - genhash = tcp_v4_md5_hash_skb(newhash, - hash_expected, - NULL, skb); + genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); else - genhash = tp->af_specific->calc_md5_hash(newhash, - hash_expected, + genhash = tp->af_specific->calc_md5_hash(newhash, key, NULL, skb); - if (genhash || memcmp(hash_location, newhash, 16) != 0) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); if (family == AF_INET) { diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 624f6cffa123..d541bc136ae7 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -310,6 +310,27 @@ int tcp_v4_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key, htonl(tcp_rsk(req)->rcv_isn)); } +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); +} + +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); + else + return tcp_v6_ao_calc_key_skb(mkt, key, skb, sisn, disn); +} + static int tcp_v4_ao_hash_pseudoheader(struct tcp_sigpool *hp, __be32 daddr, __be32 saddr, int nbytes) @@ -656,6 +677,139 @@ void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb, treq->maclen = tcp_ao_maclen(key); } +static enum skb_drop_reason +tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb, + unsigned short int family, struct tcp_ao_info *info, + const struct tcp_ao_hdr *aoh, struct tcp_ao_key *key, + u8 *traffic_key, u8 *phash, u32 sne) +{ + unsigned char newhash[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + u8 maclen = aoh->length - sizeof(struct tcp_ao_hdr); + const struct tcphdr *th = tcp_hdr(skb); + + if (maclen != tcp_ao_maclen(key)) + return SKB_DROP_REASON_TCP_AOFAILURE; + + /* XXX: make it per-AF callback? */ + tcp_ao_hash_skb(family, newhash, key, sk, skb, traffic_key, + (phash - (u8 *)th), sne); + if (memcmp(phash, newhash, maclen)) + return SKB_DROP_REASON_TCP_AOFAILURE; + return SKB_NOT_DROPPED_YET; +} + +enum skb_drop_reason +tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb, + unsigned short int family, const struct request_sock *req, + const struct tcp_ao_hdr *aoh) +{ + u8 key_buf[TCP_AO_MAX_HASH_SIZE] __tcp_ao_key_align; + const struct tcphdr *th = tcp_hdr(skb); + u8 *phash = (u8 *)(aoh + 1); /* hash goes just after the header */ + struct tcp_ao_info *info; + struct tcp_ao_key *key; + __be32 sisn, disn; + u8 *traffic_key; + u32 sne = 0; + + info = rcu_dereference(tcp_sk(sk)->ao_info); + if (!info) + return SKB_DROP_REASON_TCP_AOUNEXPECTED; + + if (unlikely(th->syn)) { + sisn = th->seq; + disn = 0; + } + + /* Fast-path */ + /* TODO: fix fastopen and simultaneous open (TCPF_SYN_RECV) */ + if (likely((1 << sk->sk_state) & (TCP_AO_ESTABLISHED | TCPF_SYN_RECV))) { + enum skb_drop_reason err; + + /* Check if this socket's rnext_key matches the keyid in the + * packet. If not we lookup the key based on the keyid + * matching the rcvid in the mkt. + */ + key = info->rnext_key; + if (key->rcvid != aoh->keyid) { + key = tcp_ao_matched_key(info, -1, aoh->keyid); + if (!key) + goto key_not_found; + } + + /* Delayed retransmitted SYN */ + if (unlikely(th->syn && !th->ack)) + goto verify_hash; + + sne = tcp_ao_compute_sne(info->rcv_sne, info->rcv_sne_seq, + ntohl(th->seq)); + /* Established socket, traffic key are cached */ + traffic_key = rcv_other_key(key); + err = tcp_ao_verify_hash(sk, skb, family, info, aoh, key, + traffic_key, phash, sne); + if (err) + return err; + /* Key rotation: the peer asks us to use new key (RNext) */ + if (unlikely(aoh->rnext_keyid != info->current_key->sndid)) { + /* If the key is not found we do nothing. */ + key = tcp_ao_matched_key(info, aoh->rnext_keyid, -1); + if (key) + /* pairs with tcp_ao_del_cmd */ + WRITE_ONCE(info->current_key, key); + } + return SKB_NOT_DROPPED_YET; + } + + /* Lookup key based on peer address and keyid. + * current_key and rnext_key must not be used on tcp listen + * sockets as otherwise: + * - request sockets would race on those key pointers + * - tcp_ao_del_cmd() allows async key removal + */ + key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid); + if (!key) + goto key_not_found; + + if (th->syn && !th->ack) + goto verify_hash; + + if (sk->sk_state == TCP_LISTEN) { + /* Make the initial syn the likely case here */ + if (unlikely(req)) { + sne = tcp_ao_compute_sne(0, tcp_rsk(req)->rcv_isn, + ntohl(th->seq)); + sisn = htonl(tcp_rsk(req)->rcv_isn); + disn = htonl(tcp_rsk(req)->snt_isn); + } else if (unlikely(th->ack && !th->syn)) { + /* Possible syncookie packet */ + sisn = htonl(ntohl(th->seq) - 1); + disn = htonl(ntohl(th->ack_seq) - 1); + sne = tcp_ao_compute_sne(0, ntohl(sisn), + ntohl(th->seq)); + } else if (unlikely(!th->syn)) { + /* no way to figure out initial sisn/disn - drop */ + return SKB_DROP_REASON_TCP_FLAGS; + } + } else if (sk->sk_state == TCP_SYN_SENT) { + disn = info->lisn; + if (th->syn) + sisn = th->seq; + else + sisn = info->risn; + } else { + WARN_ONCE(1, "TCP-AO: Unknown sk_state %d", sk->sk_state); + return SKB_DROP_REASON_TCP_AOFAILURE; + } +verify_hash: + traffic_key = key_buf; + tcp_ao_calc_key_skb(key, traffic_key, skb, sisn, disn, family); + return tcp_ao_verify_hash(sk, skb, family, info, aoh, key, + traffic_key, phash, sne); + +key_not_found: + return SKB_DROP_REASON_TCP_AOKEYNOTFOUND; +} + int tcp_ao_cache_traffic_keys(const struct sock *sk, struct tcp_ao_info *ao, struct tcp_ao_key *ao_key) { diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 693260f00abc..f6a3dde66c12 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2213,9 +2213,9 @@ int tcp_v4_rcv(struct sk_buff *skb) if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) drop_reason = SKB_DROP_REASON_XFRM_POLICY; else - drop_reason = tcp_inbound_md5_hash(sk, skb, - &iph->saddr, &iph->daddr, - AF_INET, dif, sdif); + drop_reason = tcp_inbound_hash(sk, req, skb, + &iph->saddr, &iph->daddr, + AF_INET, dif, sdif); if (unlikely(drop_reason)) { sk_drops_add(sk, skb); reqsk_put(req); @@ -2291,8 +2291,8 @@ int tcp_v4_rcv(struct sk_buff *skb) goto discard_and_relse; } - drop_reason = tcp_inbound_md5_hash(sk, skb, &iph->saddr, - &iph->daddr, AF_INET, dif, sdif); + drop_reason = tcp_inbound_hash(sk, NULL, skb, &iph->saddr, &iph->daddr, + AF_INET, dif, sdif); if (drop_reason) goto discard_and_relse; diff --git a/net/ipv6/tcp_ao.c b/net/ipv6/tcp_ao.c index 0285488db9e8..77dfa706349c 100644 --- a/net/ipv6/tcp_ao.c +++ b/net/ipv6/tcp_ao.c @@ -39,6 +39,18 @@ static int tcp_v6_ao_calc_key(struct tcp_ao_key *mkt, u8 *key, return tcp_ao_calc_traffic_key(mkt, key, &tmp, sizeof(tmp)); } +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) diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index ced00e934262..96a4b62b1fef 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1817,9 +1817,9 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) struct sock *nsk; sk = req->rsk_listener; - drop_reason = tcp_inbound_md5_hash(sk, skb, - &hdr->saddr, &hdr->daddr, - AF_INET6, dif, sdif); + drop_reason = tcp_inbound_hash(sk, req, skb, + &hdr->saddr, &hdr->daddr, + AF_INET6, dif, sdif); if (drop_reason) { sk_drops_add(sk, skb); reqsk_put(req); @@ -1891,8 +1891,8 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) goto discard_and_relse; } - drop_reason = tcp_inbound_md5_hash(sk, skb, &hdr->saddr, &hdr->daddr, - AF_INET6, dif, sdif); + drop_reason = tcp_inbound_hash(sk, NULL, skb, &hdr->saddr, &hdr->daddr, + AF_INET6, dif, sdif); if (drop_reason) goto discard_and_relse; @@ -2118,6 +2118,7 @@ static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { .ao_lookup = tcp_v6_ao_lookup, .calc_ao_hash = tcp_v4_ao_hash_skb, .ao_parse = tcp_v6_parse_ao, + .ao_calc_key_sk = tcp_v4_ao_calc_key_sk, #endif }; #endif