inet_diag: factorize code in new inet_diag_msg_common_fill() helper

Now the three type of sockets share a common base, we can factorize
code in inet_diag_msg_common_fill().

inet_diag_entry no longer requires saddr_storage & daddr_storage
and the extra copies.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index d827fe2e3ce0a38a68ceb83a5dcd81a254944e63..ac7b5c909fe7b5d293a09120b0df024815c032eb 100644 (file)
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -44,10 +44,6 @@ struct inet_diag_entry {
        u16 dport;
        u16 family;
        u16 userlocks;
-#if IS_ENABLED(CONFIG_IPV6)
-       struct in6_addr saddr_storage;  /* for IPv4-mapped-IPv6 addresses */
-       struct in6_addr daddr_storage;  /* for IPv4-mapped-IPv6 addresses */
-#endif
 };
 
 static DEFINE_MUTEX(inet_diag_table_mutex);
@@ -70,6 +66,30 @@ static void inet_diag_unlock_handler(const struct inet_diag_handler *handler)
        mutex_unlock(&inet_diag_table_mutex);
 }
 
+static void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk)
+{
+       r->idiag_family = sk->sk_family;
+
+       r->id.idiag_sport = htons(sk->sk_num);
+       r->id.idiag_dport = sk->sk_dport;
+       r->id.idiag_if = sk->sk_bound_dev_if;
+       sock_diag_save_cookie(sk, r->id.idiag_cookie);
+
+#if IS_ENABLED(CONFIG_IPV6)
+       if (sk->sk_family == AF_INET6) {
+               *(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
+               *(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
+       } else
+#endif
+       {
+       memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
+       memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
+
+       r->id.idiag_src[0] = sk->sk_rcv_saddr;
+       r->id.idiag_dst[0] = sk->sk_daddr;
+       }
+}
+
 int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
                      struct sk_buff *skb, const struct inet_diag_req_v2 *req,
                      struct user_namespace *user_ns,
@@ -95,22 +115,11 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
        r = nlmsg_data(nlh);
        BUG_ON((1 << sk->sk_state) & (TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV));
 
-       r->idiag_family = sk->sk_family;
+       inet_diag_msg_common_fill(r, sk);
        r->idiag_state = sk->sk_state;
        r->idiag_timer = 0;
        r->idiag_retrans = 0;
 
-       r->id.idiag_if = sk->sk_bound_dev_if;
-       sock_diag_save_cookie(sk, r->id.idiag_cookie);
-
-       r->id.idiag_sport = inet->inet_sport;
-       r->id.idiag_dport = inet->inet_dport;
-
-       memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
-       memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
-
-       r->id.idiag_src[0] = inet->inet_rcv_saddr;
-       r->id.idiag_dst[0] = inet->inet_daddr;
 
        if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown))
                goto errout;
@@ -124,9 +133,6 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 
 #if IS_ENABLED(CONFIG_IPV6)
        if (r->idiag_family == AF_INET6) {
-               *(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
-               *(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
-
                if (ext & (1 << (INET_DIAG_TCLASS - 1)))
                        if (nla_put_u8(skb, INET_DIAG_TCLASS,
                                       inet6_sk(sk)->tclass) < 0)
@@ -244,21 +250,9 @@ static int inet_twsk_diag_fill(struct sock *sk,
        if (tmo < 0)
                tmo = 0;
 
-       r->idiag_family       = tw->tw_family;
+       inet_diag_msg_common_fill(r, sk);
        r->idiag_retrans      = 0;
 
-       r->id.idiag_if        = tw->tw_bound_dev_if;
-       sock_diag_save_cookie(sk, r->id.idiag_cookie);
-
-       r->id.idiag_sport     = tw->tw_sport;
-       r->id.idiag_dport     = tw->tw_dport;
-
-       memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
-       memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
-
-       r->id.idiag_src[0]    = tw->tw_rcv_saddr;
-       r->id.idiag_dst[0]    = tw->tw_daddr;
-
        r->idiag_state        = tw->tw_substate;
        r->idiag_timer        = 3;
        r->idiag_expires      = jiffies_to_msecs(tmo);
@@ -266,12 +260,6 @@ static int inet_twsk_diag_fill(struct sock *sk,
        r->idiag_wqueue       = 0;
        r->idiag_uid          = 0;
        r->idiag_inode        = 0;
-#if IS_ENABLED(CONFIG_IPV6)
-       if (tw->tw_family == AF_INET6) {
-               *(struct in6_addr *)r->id.idiag_src = tw->tw_v6_rcv_saddr;
-               *(struct in6_addr *)r->id.idiag_dst = tw->tw_v6_daddr;
-       }
-#endif
 
        nlmsg_end(skb, nlh);
        return 0;
@@ -485,6 +473,23 @@ static int inet_diag_bc_run(const struct nlattr *_bc,
        return len == 0;
 }
 
+/* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV)
+ */
+static void entry_fill_addrs(struct inet_diag_entry *entry,
+                            const struct sock *sk)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+       if (sk->sk_family == AF_INET6) {
+               entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32;
+               entry->daddr = sk->sk_v6_daddr.s6_addr32;
+       } else
+#endif
+       {
+               entry->saddr = &sk->sk_rcv_saddr;
+               entry->daddr = &sk->sk_daddr;
+       }
+}
+
 int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
 {
        struct inet_sock *inet = inet_sk(sk);
@@ -494,16 +499,7 @@ int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
                return 1;
 
        entry.family = sk->sk_family;
-#if IS_ENABLED(CONFIG_IPV6)
-       if (entry.family == AF_INET6) {
-               entry.saddr = sk->sk_v6_rcv_saddr.s6_addr32;
-               entry.daddr = sk->sk_v6_daddr.s6_addr32;
-       } else
-#endif
-       {
-               entry.saddr = &inet->inet_rcv_saddr;
-               entry.daddr = &inet->inet_daddr;
-       }
+       entry_fill_addrs(&entry, sk);
        entry.sport = inet->inet_num;
        entry.dport = ntohs(inet->inet_dport);
        entry.userlocks = (sk->sk_state != TCP_TIME_WAIT) ? sk->sk_userlocks : 0;
@@ -681,36 +677,6 @@ static int inet_twsk_diag_dump(struct sock *sk,
                                   cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
 }
 
-/* Get the IPv4, IPv6, or IPv4-mapped-IPv6 local and remote addresses
- * from a request_sock. For IPv4-mapped-IPv6 we must map IPv4 to IPv6.
- */
-static void inet_diag_req_addrs(const struct sock *sk,
-                               const struct request_sock *req,
-                               struct inet_diag_entry *entry)
-{
-       const struct inet_request_sock *ireq = inet_rsk(req);
-
-#if IS_ENABLED(CONFIG_IPV6)
-       if (sk->sk_family == AF_INET6) {
-               if (req->rsk_ops->family == AF_INET6) {
-                       entry->saddr = ireq->ir_v6_loc_addr.s6_addr32;
-                       entry->daddr = ireq->ir_v6_rmt_addr.s6_addr32;
-               } else if (req->rsk_ops->family == AF_INET) {
-                       ipv6_addr_set_v4mapped(ireq->ir_loc_addr,
-                                              &entry->saddr_storage);
-                       ipv6_addr_set_v4mapped(ireq->ir_rmt_addr,
-                                              &entry->daddr_storage);
-                       entry->saddr = entry->saddr_storage.s6_addr32;
-                       entry->daddr = entry->daddr_storage.s6_addr32;
-               }
-       } else
-#endif
-       {
-               entry->saddr = &ireq->ir_loc_addr;
-               entry->daddr = &ireq->ir_rmt_addr;
-       }
-}
-
 static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
                              struct request_sock *req,
                              struct user_namespace *user_ns,
@@ -728,44 +694,23 @@ static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
                return -EMSGSIZE;
 
        r = nlmsg_data(nlh);
-       r->idiag_family = ireq->ireq_family;
+       inet_diag_msg_common_fill(r, (struct sock *)ireq);
        r->idiag_state = TCP_SYN_RECV;
        r->idiag_timer = 1;
        r->idiag_retrans = req->num_retrans;
 
-       r->id.idiag_if = ireq->ir_iif;
-
        BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
                     offsetof(struct sock, sk_cookie));
-       sock_diag_save_cookie((struct sock *)ireq, r->id.idiag_cookie);
 
        tmo = req->expires - jiffies;
        if (tmo < 0)
                tmo = 0;
 
-       r->id.idiag_sport = htons(ireq->ir_num);
-       r->id.idiag_dport = ireq->ir_rmt_port;
-
-       memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
-       memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
-
-       r->id.idiag_src[0] = ireq->ir_loc_addr;
-       r->id.idiag_dst[0] = ireq->ir_rmt_addr;
-
        r->idiag_expires = jiffies_to_msecs(tmo);
        r->idiag_rqueue = 0;
        r->idiag_wqueue = 0;
        r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
        r->idiag_inode = 0;
-#if IS_ENABLED(CONFIG_IPV6)
-       if (r->idiag_family == AF_INET6) {
-               struct inet_diag_entry entry;
-
-               inet_diag_req_addrs(sk, req, &entry);
-               memcpy(r->id.idiag_src, entry.saddr, sizeof(struct in6_addr));
-               memcpy(r->id.idiag_dst, entry.daddr, sizeof(struct in6_addr));
-       }
-#endif
 
        nlmsg_end(skb, nlh);
        return 0;
@@ -816,7 +761,8 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
                                continue;
 
                        if (bc) {
-                               inet_diag_req_addrs(sk, req, &entry);
+                               /* Note: entry.sport and entry.userlocks are already set */
+                               entry_fill_addrs(&entry, (struct sock *)req);
                                entry.dport = ntohs(ireq->ir_rmt_port);
 
                                if (!inet_diag_bc_run(bc, &entry))