CIFS: Simplify ipv*_connect functions into one (try #4)

Make connect logic more ip-protocol independent and move RFC1001 stuff into
a separate function. Also replace union addr in TCP_Server_Info structure
with sockaddr_storage.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-and-Tested-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 159 insertions, 224 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index cc1a8604a790..b90c7411f4f0 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -115,8 +115,8 @@ struct smb_vol {
 #define TLINK_ERROR_EXPIRE      (1 * HZ)
 #define TLINK_IDLE_EXPIRE       (600 * HZ)
 
-static int ipv4_connect(struct TCP_Server_Info *server);
-static int ipv6_connect(struct TCP_Server_Info *server);
+static int ip_connect(struct TCP_Server_Info *server);
+static int generic_ip_connect(struct TCP_Server_Info *server);
 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
 static void cifs_prune_tlinks(struct work_struct *work);
 
@@ -200,10 +200,9 @@ cifs_reconnect(struct TCP_Server_Info *server)
         while ((server->tcpStatus != CifsExiting) &&
                (server->tcpStatus != CifsGood)) {
                 try_to_freeze();
-                if (server->addr.sockAddr6.sin6_family == AF_INET6)
-                        rc = ipv6_connect(server);
-                else
-                        rc = ipv4_connect(server);
+
+                /* we should try only the port we connected to before */
+                rc = generic_ip_connect(server);
                 if (rc) {
                         cFYI(1, "reconnect error %d", rc);
                         msleep(3000);
@@ -477,7 +476,7 @@ incomplete_rcv:
                          * initialize frame)
                          */
                         cifs_set_port((struct sockaddr *)
-                                        &server->addr.sockAddr, CIFS_PORT);
+                                        &server->dstaddr, CIFS_PORT);
                         cifs_reconnect(server);
                         csocket = server->ssocket;
                         wake_up(&server->response_q);
@@ -1459,30 +1458,37 @@ static bool
 match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
               struct sockaddr *srcaddr)
 {
-        struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
-        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
-
         switch (addr->sa_family) {
-        case AF_INET:
-                if (addr4->sin_addr.s_addr !=
-                    server->addr.sockAddr.sin_addr.s_addr)
+        case AF_INET: {
+                struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
+                struct sockaddr_in *srv_addr4 =
+                                        (struct sockaddr_in *)&server->dstaddr;
+
+                if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
                         return false;
-                if (addr4->sin_port &&
-                    addr4->sin_port != server->addr.sockAddr.sin_port)
+                if (addr4->sin_port && addr4->sin_port != srv_addr4->sin_port)
                         return false;
                 break;
-        case AF_INET6:
+        }
+        case AF_INET6: {
+                struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
+                struct sockaddr_in6 *srv_addr6 =
+                                        (struct sockaddr_in6 *)&server->dstaddr;
+
                 if (!ipv6_addr_equal(&addr6->sin6_addr,
-                                     &server->addr.sockAddr6.sin6_addr))
+                                     &srv_addr6->sin6_addr))
                         return false;
-                if (addr6->sin6_scope_id !=
-                    server->addr.sockAddr6.sin6_scope_id)
+                if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
                         return false;
                 if (addr6->sin6_port &&
-                    addr6->sin6_port != server->addr.sockAddr6.sin6_port)
+                    addr6->sin6_port != srv_addr6->sin6_port)
                         return false;
                 break;
         }
+        default:
+                WARN_ON(1);
+                return false; /* don't expect to be here */
+        }
 
         if (!srcip_matches(srcaddr, (struct sockaddr *)&server->srcaddr))
                 return false;
@@ -1681,14 +1687,13 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
                 cFYI(1, "attempting ipv6 connect");
                 /* BB should we allow ipv6 on port 139? */
                 /* other OS never observed in Wild doing 139 with v6 */
-                memcpy(&tcp_ses->addr.sockAddr6, sin_server6,
-                        sizeof(struct sockaddr_in6));
-                rc = ipv6_connect(tcp_ses);
-        } else {
-                memcpy(&tcp_ses->addr.sockAddr, sin_server,
-                        sizeof(struct sockaddr_in));
-                rc = ipv4_connect(tcp_ses);
-        }
+                memcpy(&tcp_ses->dstaddr, sin_server6,
+                       sizeof(struct sockaddr_in6));
+        } else
+                memcpy(&tcp_ses->dstaddr, sin_server,
+                       sizeof(struct sockaddr_in));
+
+        rc = ip_connect(tcp_ses);
         if (rc < 0) {
                 cERROR(1, "Error connecting to socket. Aborting operation");
                 goto out_err_crypto_release;
@@ -1793,6 +1798,8 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 {
         int rc = -ENOMEM, xid;
         struct cifsSesInfo *ses;
+        struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
+        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
 
         xid = GetXid();
 
@@ -1836,12 +1843,10 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 
         /* new SMB session uses our server ref */
         ses->server = server;
-        if (server->addr.sockAddr6.sin6_family == AF_INET6)
-                sprintf(ses->serverName, "%pI6",
-                        &server->addr.sockAddr6.sin6_addr);
+        if (server->dstaddr.ss_family == AF_INET6)
+                sprintf(ses->serverName, "%pI6", &addr6->sin6_addr);
         else
-                sprintf(ses->serverName, "%pI4",
-                        &server->addr.sockAddr.sin_addr.s_addr);
+                sprintf(ses->serverName, "%pI4", &addr->sin_addr);
 
         if (volume_info->username)
                 strncpy(ses->userName, volume_info->username,
@@ -2136,19 +2141,106 @@ bind_socket(struct TCP_Server_Info *server)
 }
 
 static int
-ipv4_connect(struct TCP_Server_Info *server)
+ip_rfc1001_connect(struct TCP_Server_Info *server)
 {
         int rc = 0;
-        int val;
-        bool connected = false;
-        __be16 orig_port = 0;
+        /*
+         * some servers require RFC1001 sessinit before sending
+         * negprot - BB check reconnection in case where second
+         * sessinit is sent but no second negprot
+         */
+        struct rfc1002_session_packet *ses_init_buf;
+        struct smb_hdr *smb_buf;
+        ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
+                               GFP_KERNEL);
+        if (ses_init_buf) {
+                ses_init_buf->trailer.session_req.called_len = 32;
+
+                if (server->server_RFC1001_name &&
+                    server->server_RFC1001_name[0] != 0)
+                        rfc1002mangle(ses_init_buf->trailer.
+                                      session_req.called_name,
+                                      server->server_RFC1001_name,
+                                      RFC1001_NAME_LEN_WITH_NULL);
+                else
+                        rfc1002mangle(ses_init_buf->trailer.
+                                      session_req.called_name,
+                                      DEFAULT_CIFS_CALLED_NAME,
+                                      RFC1001_NAME_LEN_WITH_NULL);
+
+                ses_init_buf->trailer.session_req.calling_len = 32;
+
+                /*
+                 * calling name ends in null (byte 16) from old smb
+                 * convention.
+                 */
+                if (server->workstation_RFC1001_name &&
+                    server->workstation_RFC1001_name[0] != 0)
+                        rfc1002mangle(ses_init_buf->trailer.
+                                      session_req.calling_name,
+                                      server->workstation_RFC1001_name,
+                                      RFC1001_NAME_LEN_WITH_NULL);
+                else
+                        rfc1002mangle(ses_init_buf->trailer.
+                                      session_req.calling_name,
+                                      "LINUX_CIFS_CLNT",
+                                      RFC1001_NAME_LEN_WITH_NULL);
+
+                ses_init_buf->trailer.session_req.scope1 = 0;
+                ses_init_buf->trailer.session_req.scope2 = 0;
+                smb_buf = (struct smb_hdr *)ses_init_buf;
+
+                /* sizeof RFC1002_SESSION_REQUEST with no scope */
+                smb_buf->smb_buf_length = 0x81000044;
+                rc = smb_send(server, smb_buf, 0x44);
+                kfree(ses_init_buf);
+                /*
+                 * RFC1001 layer in at least one server
+                 * requires very short break before negprot
+                 * presumably because not expecting negprot
+                 * to follow so fast.  This is a simple
+                 * solution that works without
+                 * complicating the code and causes no
+                 * significant slowing down on mount
+                 * for everyone else
+                 */
+                usleep_range(1000, 2000);
+        }
+        /*
+         * else the negprot may still work without this
+         * even though malloc failed
+         */
+
+        return rc;
+}
+
+static int
+generic_ip_connect(struct TCP_Server_Info *server)
+{
+        int rc = 0;
+        unsigned short int sport;
+        int slen, sfamily;
         struct socket *socket = server->ssocket;
+        struct sockaddr *saddr;
+
+        saddr = (struct sockaddr *) &server->dstaddr;
+
+        if (server->dstaddr.ss_family == AF_INET6) {
+                sport = ((struct sockaddr_in6 *) saddr)->sin6_port;
+                slen = sizeof(struct sockaddr_in6);
+                sfamily = AF_INET6;
+        } else {
+                sport = ((struct sockaddr_in *) saddr)->sin_port;
+                slen = sizeof(struct sockaddr_in);
+                sfamily = AF_INET;
+        }
 
         if (socket == NULL) {
-                rc = sock_create_kern(PF_INET, SOCK_STREAM,
+                rc = sock_create_kern(sfamily, SOCK_STREAM,
                                       IPPROTO_TCP, &socket);
                 if (rc < 0) {
                         cERROR(1, "Error %d creating socket", rc);
+                        server->ssocket = NULL;
                         return rc;
                 }
 
@@ -2156,63 +2248,28 @@ ipv4_connect(struct TCP_Server_Info *server)
                 cFYI(1, "Socket created");
                 server->ssocket = socket;
                 socket->sk->sk_allocation = GFP_NOFS;
-                cifs_reclassify_socket4(socket);
+                if (sfamily == AF_INET6)
+                        cifs_reclassify_socket6(socket);
+                else
+                        cifs_reclassify_socket4(socket);
         }
 
         rc = bind_socket(server);
         if (rc < 0)
                 return rc;
 
-        /* user overrode default port */
-        if (server->addr.sockAddr.sin_port) {
-                rc = socket->ops->connect(socket, (struct sockaddr *)
-                                          &server->addr.sockAddr,
-                                          sizeof(struct sockaddr_in), 0);
-                if (rc >= 0)
-                        connected = true;
-        }
-
-        if (!connected) {
-                /* save original port so we can retry user specified port
-                        later if fall back ports fail this time  */
-                orig_port = server->addr.sockAddr.sin_port;
-
-                /* do not retry on the same port we just failed on */
-                if (server->addr.sockAddr.sin_port != htons(CIFS_PORT)) {
-                        server->addr.sockAddr.sin_port = htons(CIFS_PORT);
-                        rc = socket->ops->connect(socket,
-                                                (struct sockaddr *)
-                                                &server->addr.sockAddr,
-                                                sizeof(struct sockaddr_in), 0);
-                        if (rc >= 0)
-                                connected = true;
-                }
-        }
-        if (!connected) {
-                server->addr.sockAddr.sin_port = htons(RFC1001_PORT);
-                rc = socket->ops->connect(socket, (struct sockaddr *)
-                                              &server->addr.sockAddr,
-                                              sizeof(struct sockaddr_in), 0);
-                if (rc >= 0)
-                        connected = true;
-        }
-
-        /* give up here - unless we want to retry on different
-                protocol families some day */
-        if (!connected) {
-                if (orig_port)
-                        server->addr.sockAddr.sin_port = orig_port;
-                cFYI(1, "Error %d connecting to server via ipv4", rc);
+        rc = socket->ops->connect(socket, saddr, slen, 0);
+        if (rc < 0) {
+                cFYI(1, "Error %d connecting to server", rc);
                 sock_release(socket);
                 server->ssocket = NULL;
                 return rc;
         }
 
-
         /*
          * Eventually check for other socket options to change from
-         *  the default. sock_setsockopt not used because it expects
-         *  user space buffer
+         * the default. sock_setsockopt not used because it expects
+         * user space buffer
          */
         socket->sk->sk_rcvtimeo = 7 * HZ;
         socket->sk->sk_sndtimeo = 5 * HZ;
@@ -2226,7 +2283,7 @@ ipv4_connect(struct TCP_Server_Info *server)
         }
 
         if (server->tcp_nodelay) {
-                val = 1;
+                int val = 1;
                 rc = kernel_setsockopt(socket, SOL_TCP, TCP_NODELAY,
                                 (char *)&val, sizeof(val));
                 if (rc)
@@ -2237,161 +2294,39 @@ ipv4_connect(struct TCP_Server_Info *server)
                  socket->sk->sk_sndbuf,
                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
 
-        /* send RFC1001 sessinit */
-        if (server->addr.sockAddr.sin_port == htons(RFC1001_PORT)) {
-                /* some servers require RFC1001 sessinit before sending
-                negprot - BB check reconnection in case where second
-                sessinit is sent but no second negprot */
-                struct rfc1002_session_packet *ses_init_buf;
-                struct smb_hdr *smb_buf;
-                ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
-                                       GFP_KERNEL);
-                if (ses_init_buf) {
-                        ses_init_buf->trailer.session_req.called_len = 32;
-                        if (server->server_RFC1001_name &&
-                            server->server_RFC1001_name[0] != 0)
-                                rfc1002mangle(ses_init_buf->trailer.
-                                                session_req.called_name,
-                                              server->server_RFC1001_name,
-                                              RFC1001_NAME_LEN_WITH_NULL);
-                        else
-                                rfc1002mangle(ses_init_buf->trailer.
-                                                session_req.called_name,
-                                              DEFAULT_CIFS_CALLED_NAME,
-                                              RFC1001_NAME_LEN_WITH_NULL);
-
-                        ses_init_buf->trailer.session_req.calling_len = 32;
-
-                        /* calling name ends in null (byte 16) from old smb
-                        convention. */
-                        if (server->workstation_RFC1001_name &&
-                            server->workstation_RFC1001_name[0] != 0)
-                                rfc1002mangle(ses_init_buf->trailer.
-                                                session_req.calling_name,
-                                              server->workstation_RFC1001_name,
-                                              RFC1001_NAME_LEN_WITH_NULL);
-                        else
-                                rfc1002mangle(ses_init_buf->trailer.
-                                                session_req.calling_name,
-                                              "LINUX_CIFS_CLNT",
-                                              RFC1001_NAME_LEN_WITH_NULL);
-
-                        ses_init_buf->trailer.session_req.scope1 = 0;
-                        ses_init_buf->trailer.session_req.scope2 = 0;
-                        smb_buf = (struct smb_hdr *)ses_init_buf;
-                        /* sizeof RFC1002_SESSION_REQUEST with no scope */
-                        smb_buf->smb_buf_length = 0x81000044;
-                        rc = smb_send(server, smb_buf, 0x44);
-                        kfree(ses_init_buf);
-                        msleep(1); /* RFC1001 layer in at least one server
-                                      requires very short break before negprot
-                                      presumably because not expecting negprot
-                                      to follow so fast.  This is a simple
-                                      solution that works without
-                                      complicating the code and causes no
-                                      significant slowing down on mount
-                                      for everyone else */
-                }
-                /* else the negprot may still work without this
-                even though malloc failed */
-
-        }
+        if (sport == htons(RFC1001_PORT))
+                rc = ip_rfc1001_connect(server);
 
         return rc;
 }
 
 static int
-ipv6_connect(struct TCP_Server_Info *server)
+ip_connect(struct TCP_Server_Info *server)
 {
-        int rc = 0;
-        int val;
-        bool connected = false;
-        __be16 orig_port = 0;
-        struct socket *socket = server->ssocket;
+        unsigned short int *sport;
+        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
+        struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
 
-        if (socket == NULL) {
-                rc = sock_create_kern(PF_INET6, SOCK_STREAM,
-                                      IPPROTO_TCP, &socket);
-                if (rc < 0) {
-                        cERROR(1, "Error %d creating ipv6 socket", rc);
-                        socket = NULL;
-                        return rc;
-                }
+        if (server->dstaddr.ss_family == AF_INET6)
+                sport = &addr6->sin6_port;
+        else
+                sport = &addr->sin_port;
 
-                /* BB other socket options to set KEEPALIVE, NODELAY? */
-                cFYI(1, "ipv6 Socket created");
-                server->ssocket = socket;
-                socket->sk->sk_allocation = GFP_NOFS;
-                cifs_reclassify_socket6(socket);
-        }
+        if (*sport == 0) {
+                int rc;
 
-        rc = bind_socket(server);
-        if (rc < 0)
-                return rc;
+                /* try with 445 port at first */
+                *sport = htons(CIFS_PORT);
 
-        /* user overrode default port */
-        if (server->addr.sockAddr6.sin6_port) {
-                rc = socket->ops->connect(socket,
-                                (struct sockaddr *) &server->addr.sockAddr6,
-                                sizeof(struct sockaddr_in6), 0);
-                if (rc >= 0)
-                        connected = true;
-        }
-
-        if (!connected) {
-                /* save original port so we can retry user specified port
-                        later if fall back ports fail this time  */
-
-                orig_port = server->addr.sockAddr6.sin6_port;
-                /* do not retry on the same port we just failed on */
-                if (server->addr.sockAddr6.sin6_port != htons(CIFS_PORT)) {
-                        server->addr.sockAddr6.sin6_port = htons(CIFS_PORT);
-                        rc = socket->ops->connect(socket, (struct sockaddr *)
-                                        &server->addr.sockAddr6,
-                                        sizeof(struct sockaddr_in6), 0);
-                        if (rc >= 0)
-                                connected = true;
-                }
-        }
-        if (!connected) {
-                server->addr.sockAddr6.sin6_port = htons(RFC1001_PORT);
-                rc = socket->ops->connect(socket, (struct sockaddr *)
-                                &server->addr.sockAddr6,
-                                sizeof(struct sockaddr_in6), 0);
+                rc = generic_ip_connect(server);
                 if (rc >= 0)
-                        connected = true;
-        }
-
-        /* give up here - unless we want to retry on different
-                protocol families some day */
-        if (!connected) {
-                if (orig_port)
-                        server->addr.sockAddr6.sin6_port = orig_port;
-                cFYI(1, "Error %d connecting to server via ipv6", rc);
-                sock_release(socket);
-                server->ssocket = NULL;
-                return rc;
-        }
-
-        /*
-         * Eventually check for other socket options to change from
-         * the default. sock_setsockopt not used because it expects
-         * user space buffer
-         */
-        socket->sk->sk_rcvtimeo = 7 * HZ;
-        socket->sk->sk_sndtimeo = 5 * HZ;
+                        return rc;
 
-        if (server->tcp_nodelay) {
-                val = 1;
-                rc = kernel_setsockopt(socket, SOL_TCP, TCP_NODELAY,
-                                (char *)&val, sizeof(val));
-                if (rc)
-                        cFYI(1, "set TCP_NODELAY socket option error %d", rc);
+                /* if it failed, try with 139 port */
+                *sport = htons(RFC1001_PORT);
         }
 
-        server->ssocket = socket;
-
-        return rc;
+        return generic_ip_connect(server);
 }
 
 void reset_cifs_unix_caps(int xid, struct cifsTconInfo *tcon,