[TCPDIAG]: Implement cheapest way of supporting DCCPDIAG_GETSOCK

With ugly ifdefs, etc, but this actually:

1. keeps the existing ABI, i.e. no need to recompile the iproute2
   utilities if not interested in DCCP.

2. Provides all the tcp_diag functionality in DCCP, with just a
   small patch that makes iproute2 support DCCP.

Of course I'll get this cleaned-up in time, but for now I think its
OK to be this way to quickly get this functionality.

iproute2-ss050808 patch at:

http://vger.kernel.org/~acme/iproute2-ss050808.dccp.patch

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/tcp_diag.h b/include/linux/tcp_diag.h
index 7a59967..190494e 100644 (file)
--- a/include/linux/tcp_diag.h
+++ b/include/linux/tcp_diag.h
@@ -3,6 +3,7 @@
 
 /* Just some random number */
 #define TCPDIAG_GETSOCK 18
+#define DCCPDIAG_GETSOCK 19
 
 /* Socket identity */
 struct tcpdiag_sockid

diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index f6da932..d3770ae 100644 (file)
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -34,6 +34,8 @@ struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
        .port_rover     = 1024 - 1,
 };
 
+EXPORT_SYMBOL_GPL(dccp_hashinfo);
+
 static int dccp_v4_get_port(struct sock *sk, const unsigned short snum)
 {
        return inet_csk_get_port(&dccp_hashinfo, sk, snum);

diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
index 4288ecf..f5fc84a 100644 (file)
--- a/net/ipv4/tcp_diag.c
+++ b/net/ipv4/tcp_diag.c
@@ -45,11 +45,15 @@ static struct sock *tcpnl;
 #define TCPDIAG_PUT(skb, attrtype, attrlen) \
        RTA_DATA(__RTA_PUT(skb, attrtype, attrlen))
 
+#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
+extern struct inet_hashinfo dccp_hashinfo;
+#endif
+
 static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
-                       int ext, u32 pid, u32 seq, u16 nlmsg_flags)
+                       int ext, u32 pid, u32 seq, u16 nlmsg_flags,
+                       const struct nlmsghdr *unlh)
 {
        const struct inet_sock *inet = inet_sk(sk);
-       struct tcp_sock *tp = tcp_sk(sk);
        const struct inet_connection_sock *icsk = inet_csk(sk);
        struct tcpdiagmsg *r;
        struct nlmsghdr  *nlh;
@@ -57,7 +61,7 @@ static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
        struct tcpdiag_meminfo  *minfo = NULL;
        unsigned char    *b = skb->tail;
 
-       nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
+       nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
        nlh->nlmsg_flags = nlmsg_flags;
        r = NLMSG_DATA(nlh);
        if (sk->sk_state != TCP_TIME_WAIT) {
@@ -147,8 +151,20 @@ static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
                r->tcpdiag_expires = 0;
        }
 #undef EXPIRES_IN_MS
-       r->tcpdiag_rqueue = tp->rcv_nxt - tp->copied_seq;
-       r->tcpdiag_wqueue = tp->write_seq - tp->snd_una;
+       /*
+        * Ahem... for now we'll have some knowledge about TCP -acme
+        * But this is just one of two small exceptions, both in this
+        * function, so lets close our eyes for some 15 lines or so... 8)
+        * -acme
+        */
+       if (sk->sk_protocol == IPPROTO_TCP) {
+               const struct tcp_sock *tp = tcp_sk(sk);
+
+               r->tcpdiag_rqueue = tp->rcv_nxt - tp->copied_seq;
+               r->tcpdiag_wqueue = tp->write_seq - tp->snd_una;
+       } else
+               r->tcpdiag_rqueue = r->tcpdiag_wqueue = 0;
+
        r->tcpdiag_uid = sock_i_uid(sk);
        r->tcpdiag_inode = sock_i_ino(sk);
 
@@ -159,8 +175,13 @@ static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
                minfo->tcpdiag_tmem = atomic_read(&sk->sk_wmem_alloc);
        }
 
-       if (info) 
-               tcp_get_info(sk, info);
+       /* Ahem... for now we'll have some knowledge about TCP -acme */
+       if (info) {
+               if (sk->sk_protocol == IPPROTO_TCP) 
+                       tcp_get_info(sk, info);
+               else
+                       memset(info, 0, sizeof(*info));
+       }
 
        if (sk->sk_state < TCP_TIME_WAIT &&
            icsk->icsk_ca_ops && icsk->icsk_ca_ops->get_info)
@@ -194,9 +215,13 @@ static int tcpdiag_get_exact(struct sk_buff *in_skb, const struct nlmsghdr *nlh)
        struct sock *sk;
        struct tcpdiagreq *req = NLMSG_DATA(nlh);
        struct sk_buff *rep;
-
+       struct inet_hashinfo *hashinfo = &tcp_hashinfo;
+#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
+       if (nlh->nlmsg_type == DCCPDIAG_GETSOCK)
+               hashinfo = &dccp_hashinfo;
+#endif
        if (req->tcpdiag_family == AF_INET) {
-               sk = inet_lookup(&tcp_hashinfo, req->id.tcpdiag_dst[0],
+               sk = inet_lookup(hashinfo, req->id.tcpdiag_dst[0],
                                 req->id.tcpdiag_dport, req->id.tcpdiag_src[0],
                                 req->id.tcpdiag_sport, req->id.tcpdiag_if);
        }
@@ -230,7 +255,7 @@ static int tcpdiag_get_exact(struct sk_buff *in_skb, const struct nlmsghdr *nlh)
 
        if (tcpdiag_fill(rep, sk, req->tcpdiag_ext,
                         NETLINK_CB(in_skb).pid,
-                        nlh->nlmsg_seq, 0) <= 0)
+                        nlh->nlmsg_seq, 0, nlh) <= 0)
                BUG();
 
        err = netlink_unicast(tcpnl, rep, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
@@ -436,12 +461,13 @@ static int tcpdiag_dump_sock(struct sk_buff *skb, struct sock *sk,
        }
 
        return tcpdiag_fill(skb, sk, r->tcpdiag_ext, NETLINK_CB(cb->skb).pid,
-                           cb->nlh->nlmsg_seq, NLM_F_MULTI);
+                           cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
 }
 
 static int tcpdiag_fill_req(struct sk_buff *skb, struct sock *sk,
                            struct request_sock *req,
-                           u32 pid, u32 seq)
+                           u32 pid, u32 seq,
+                           const struct nlmsghdr *unlh)
 {
        const struct inet_request_sock *ireq = inet_rsk(req);
        struct inet_sock *inet = inet_sk(sk);
@@ -450,7 +476,7 @@ static int tcpdiag_fill_req(struct sk_buff *skb, struct sock *sk,
        struct nlmsghdr *nlh;
        long tmo;
 
-       nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
+       nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
        nlh->nlmsg_flags = NLM_F_MULTI;
        r = NLMSG_DATA(nlh);
 
@@ -526,7 +552,7 @@ static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
                entry.userlocks = sk->sk_userlocks;
        }
 
-       for (j = s_j; j < TCP_SYNQ_HSIZE; j++) {
+       for (j = s_j; j < lopt->nr_table_entries; j++) {
                struct request_sock *req, *head = lopt->syn_table[j];
 
                reqnum = 0;
@@ -561,7 +587,7 @@ static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 
                        err = tcpdiag_fill_req(skb, sk, req,
                                               NETLINK_CB(cb->skb).pid,
-                                              cb->nlh->nlmsg_seq);
+                                              cb->nlh->nlmsg_seq, cb->nlh);
                        if (err < 0) {
                                cb->args[3] = j + 1;
                                cb->args[4] = reqnum;
@@ -583,20 +609,26 @@ static int tcpdiag_dump(struct sk_buff *skb, struct netlink_callback *cb)
        int i, num;
        int s_i, s_num;
        struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
+       struct inet_hashinfo *hashinfo;
 
        s_i = cb->args[1];
        s_num = num = cb->args[2];
-
+               hashinfo = &tcp_hashinfo;
+#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
+       if (cb->nlh->nlmsg_type == DCCPDIAG_GETSOCK)
+               hashinfo = &dccp_hashinfo;
+#endif
        if (cb->args[0] == 0) {
                if (!(r->tcpdiag_states&(TCPF_LISTEN|TCPF_SYN_RECV)))
                        goto skip_listen_ht;
-               inet_listen_lock(&tcp_hashinfo);
+
+               inet_listen_lock(hashinfo);
                for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
                        struct sock *sk;
                        struct hlist_node *node;
 
                        num = 0;
-                       sk_for_each(sk, node, &tcp_hashinfo.listening_hash[i]) {
+                       sk_for_each(sk, node, &hashinfo->listening_hash[i]) {
                                struct inet_sock *inet = inet_sk(sk);
 
                                if (num < s_num) {
@@ -614,7 +646,7 @@ static int tcpdiag_dump(struct sk_buff *skb, struct netlink_callback *cb)
                                        goto syn_recv;
 
                                if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
-                                       inet_listen_unlock(&tcp_hashinfo);
+                                       inet_listen_unlock(hashinfo);
                                        goto done;
                                }
 
@@ -623,7 +655,7 @@ syn_recv:
                                        goto next_listen;
 
                                if (tcpdiag_dump_reqs(skb, sk, cb) < 0) {
-                                       inet_listen_unlock(&tcp_hashinfo);
+                                       inet_listen_unlock(hashinfo);
                                        goto done;
                                }
 
@@ -637,7 +669,7 @@ next_listen:
                        cb->args[3] = 0;
                        cb->args[4] = 0;
                }
-               inet_listen_unlock(&tcp_hashinfo);
+               inet_listen_unlock(hashinfo);
 skip_listen_ht:
                cb->args[0] = 1;
                s_i = num = s_num = 0;
@@ -646,8 +678,8 @@ skip_listen_ht:
        if (!(r->tcpdiag_states&~(TCPF_LISTEN|TCPF_SYN_RECV)))
                return skb->len;
 
-       for (i = s_i; i < tcp_hashinfo.ehash_size; i++) {
-               struct inet_ehash_bucket *head = &tcp_hashinfo.ehash[i];
+       for (i = s_i; i < hashinfo->ehash_size; i++) {
+               struct inet_ehash_bucket *head = &hashinfo->ehash[i];
                struct sock *sk;
                struct hlist_node *node;
 
@@ -679,7 +711,7 @@ next_normal:
 
                if (r->tcpdiag_states&TCPF_TIME_WAIT) {
                        sk_for_each(sk, node,
-                                   &tcp_hashinfo.ehash[i + tcp_hashinfo.ehash_size].chain) {
+                                   &hashinfo->ehash[i + hashinfo->ehash_size].chain) {
                                struct inet_sock *inet = inet_sk(sk);
 
                                if (num < s_num)
@@ -719,7 +751,11 @@ tcpdiag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
                return 0;
 
-       if (nlh->nlmsg_type != TCPDIAG_GETSOCK)
+       if (nlh->nlmsg_type != TCPDIAG_GETSOCK
+#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
+           && nlh->nlmsg_type != DCCPDIAG_GETSOCK
+#endif
+          )
                goto err_inval;
 
        if (NLMSG_LENGTH(sizeof(struct tcpdiagreq)) > skb->len)