mptcp: unify add_addr(6)_generate_hmac

The length of the IPv4 address is 4 octets and IPv6 is 16. That's the only
difference between add_addr_generate_hmac and add_addr6_generate_hmac.

This patch dropped the duplicate code and unify them into one.

Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 3bdb92a..c7eb61d 100644 (file)
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -583,39 +583,32 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb,
        return true;
 }
 
-static u64 add_addr_generate_hmac(u64 key1, u64 key2, u8 addr_id,
-                                 struct in_addr *addr, u16 port)
-{
-       u8 hmac[SHA256_DIGEST_SIZE];
-       u8 msg[7];
-
-       msg[0] = addr_id;
-       memcpy(&msg[1], &addr->s_addr, 4);
-       msg[5] = port >> 8;
-       msg[6] = port & 0xFF;
-
-       mptcp_crypto_hmac_sha(key1, key2, msg, 7, hmac);
-
-       return get_unaligned_be64(&hmac[SHA256_DIGEST_SIZE - sizeof(u64)]);
-}
-
-#if IS_ENABLED(CONFIG_MPTCP_IPV6)
-static u64 add_addr6_generate_hmac(u64 key1, u64 key2, u8 addr_id,
-                                  struct in6_addr *addr, u16 port)
+static u64 add_addr_generate_hmac(u64 key1, u64 key2,
+                                 struct mptcp_addr_info *addr)
 {
+       u16 port = ntohs(addr->port);
        u8 hmac[SHA256_DIGEST_SIZE];
        u8 msg[19];
+       int i = 0;
 
-       msg[0] = addr_id;
-       memcpy(&msg[1], &addr->s6_addr, 16);
-       msg[17] = port >> 8;
-       msg[18] = port & 0xFF;
+       msg[i++] = addr->id;
+       if (addr->family == AF_INET) {
+               memcpy(&msg[i], &addr->addr.s_addr, 4);
+               i += 4;
+       }
+#if IS_ENABLED(CONFIG_MPTCP_IPV6)
+       else if (addr->family == AF_INET6) {
+               memcpy(&msg[i], &addr->addr6.s6_addr, 16);
+               i += 16;
+       }
+#endif
+       msg[i++] = port >> 8;
+       msg[i++] = port & 0xFF;
 
-       mptcp_crypto_hmac_sha(key1, key2, msg, 19, hmac);
+       mptcp_crypto_hmac_sha(key1, key2, msg, i, hmac);
 
        return get_unaligned_be64(&hmac[SHA256_DIGEST_SIZE - sizeof(u64)]);
 }
-#endif
 
 static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *skb,
                                               unsigned int *size,
@@ -653,26 +646,11 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
        if (drop_other_suboptions)
                *size -= opt_size;
        opts->suboptions |= OPTION_MPTCP_ADD_ADDR;
-       if (opts->addr.family == AF_INET) {
-               if (!echo) {
-                       opts->ahmac = add_addr_generate_hmac(msk->local_key,
-                                                            msk->remote_key,
-                                                            opts->addr.id,
-                                                            &opts->addr.addr,
-                                                            ntohs(opts->addr.port));
-               }
+       if (!echo) {
+               opts->ahmac = add_addr_generate_hmac(msk->local_key,
+                                                    msk->remote_key,
+                                                    &opts->addr);
        }
-#if IS_ENABLED(CONFIG_MPTCP_IPV6)
-       else if (opts->addr.family == AF_INET6) {
-               if (!echo) {
-                       opts->ahmac = add_addr6_generate_hmac(msk->local_key,
-                                                             msk->remote_key,
-                                                             opts->addr.id,
-                                                             &opts->addr.addr6,
-                                                             ntohs(opts->addr.port));
-               }
-       }
-#endif
        pr_debug("addr_id=%d, ahmac=%llu, echo=%d, port=%d",
                 opts->addr.id, opts->ahmac, echo, ntohs(opts->addr.port));
 
@@ -991,18 +969,9 @@ static bool add_addr_hmac_valid(struct mptcp_sock *msk,
        if (mp_opt->echo)
                return true;
 
-       if (mp_opt->addr.family == AF_INET)
-               hmac = add_addr_generate_hmac(msk->remote_key,
-                                             msk->local_key,
-                                             mp_opt->addr.id, &mp_opt->addr.addr,
-                                             ntohs(mp_opt->addr.port));
-#if IS_ENABLED(CONFIG_MPTCP_IPV6)
-       else
-               hmac = add_addr6_generate_hmac(msk->remote_key,
-                                              msk->local_key,
-                                              mp_opt->addr.id, &mp_opt->addr.addr6,
-                                              ntohs(mp_opt->addr.port));
-#endif
+       hmac = add_addr_generate_hmac(msk->remote_key,
+                                     msk->local_key,
+                                     &mp_opt->addr);
 
        pr_debug("msk=%p, ahmac=%llu, mp_opt->ahmac=%llu\n",
                 msk, (unsigned long long)hmac,