mount.nfs: getport() should avoid modifying passed-in arguments

[nfs-utils.git] / utils / mount / network.c

diff --git a/utils/mount/network.c b/utils/mount/network.c
index efedf25462f89d0989e0903ec6634b0500e090b9..9f803a43e6c7e29561b0b62f07b47456765e8ffc 100644 (file)
--- a/utils/mount/network.c
+++ b/utils/mount/network.c
@@ -52,6 +52,10 @@
 #define NFS_PORT 2049
 #endif
 
+#define PMAP_TIMEOUT   (10)
+#define CONNECT_TIMEOUT        (20)
+#define MOUNT_TIMEOUT  (30)
+
 #if SIZEOF_SOCKLEN_T - 0 == 0
 #define socklen_t unsigned int
 #endif
@@ -158,12 +162,60 @@ int nfs_gethostbyname(const char *hostname, struct sockaddr_in *saddr)
 }
 
 /*
- * Create a socket that is locally bound to a reserved or non-reserved
- * port. For any failures, RPC_ANYSOCK is returned which will cause 
- * the RPC code to create the socket instead. 
+ * Attempt to connect a socket, but time out after "timeout" seconds.
+ *
+ * On error return, caller closes the socket.
+ */
+static int connect_to(int fd, struct sockaddr *addr,
+                       socklen_t addrlen, int timeout)
+{
+       int ret, saved;
+       fd_set rset, wset;
+       struct timeval tv = {
+               .tv_sec = timeout,
+       };
+
+       saved = fcntl(fd, F_GETFL, 0);
+       fcntl(fd, F_SETFL, saved | O_NONBLOCK);
+
+       ret = connect(fd, addr, addrlen);
+       if (ret < 0 && errno != EINPROGRESS)
+               return -1;
+       if (ret == 0)
+               goto out;
+
+       FD_ZERO(&rset);
+       FD_SET(fd, &rset);
+       wset = rset;
+       ret = select(fd + 1, &rset, &wset, NULL, &tv);
+       if (ret == 0) {
+               errno = ETIMEDOUT;
+               return -1;
+       }
+       if (FD_ISSET(fd, &rset) || FD_ISSET(fd, &wset)) {
+               int error;
+               socklen_t len = sizeof(error);
+               if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0)
+                       return -1;
+               if (error) {
+                       errno = error;
+                       return -1;
+               }
+       } else
+               return -1;
+
+out:
+       fcntl(fd, F_SETFL, saved);
+       return 0;
+}
+
+/*
+ * Create a socket that is locally bound to a reserved or non-reserved port.
+ *
+ * The caller should check rpc_createerr to determine the cause of any error.
  */
 static int get_socket(struct sockaddr_in *saddr, unsigned int p_prot,
-                       int resvp, int conn)
+                       unsigned int timeout, int resvp, int conn)
 {
        int so, cc, type;
        struct sockaddr_in laddr;
@@ -185,7 +237,8 @@ static int get_socket(struct sockaddr_in *saddr, unsigned int p_prot,
                        goto err_bind;
        }
        if (type == SOCK_STREAM || (conn && type == SOCK_DGRAM)) {
-               cc = connect(so, (struct sockaddr *)saddr, namelen);
+               cc = connect_to(so, (struct sockaddr *)saddr, namelen,
+                               timeout);
                if (cc < 0)
                        goto err_connect;
        }
@@ -250,39 +303,35 @@ static unsigned short getport(struct sockaddr_in *saddr,
                                unsigned long version,
                                unsigned int proto)
 {
+       struct sockaddr_in bind_saddr;
        unsigned short port = 0;
        int socket;
        CLIENT *clnt = NULL;
        enum clnt_stat stat;
+ 
+       bind_saddr = *saddr;
+       bind_saddr.sin_port = htons(PMAPPORT);
 
-       saddr->sin_port = htons(PMAPPORT);
-
-       /*
-        * Try to get a socket with a non-privileged port.
-        * clnt*create() will create one anyway if this
-        * fails.
-        */
-       socket = get_socket(saddr, proto, FALSE, FALSE);
+       socket = get_socket(&bind_saddr, proto, PMAP_TIMEOUT, FALSE, FALSE);
        if (socket == RPC_ANYSOCK) {
-               if (proto == IPPROTO_TCP && errno == ETIMEDOUT) {
-                       /*
-                        * TCP SYN timed out, so exit now.
-                        */
+               if (proto == IPPROTO_TCP &&
+                   rpc_createerr.cf_error.re_errno == ETIMEDOUT)
                        rpc_createerr.cf_stat = RPC_TIMEDOUT;
-               }
                return 0;
        }
 
        switch (proto) {
        case IPPROTO_UDP:
-               clnt = clntudp_bufcreate(saddr,
+               clnt = clntudp_bufcreate(&bind_saddr,
                                         PMAPPROG, PMAPVERS,
                                         RETRY_TIMEOUT, &socket,
                                         RPCSMALLMSGSIZE,
                                         RPCSMALLMSGSIZE);
                break;
        case IPPROTO_TCP:
-               clnt = clnttcp_create(saddr, PMAPPROG, PMAPVERS, &socket,
+               clnt = clnttcp_create(&bind_saddr,
+                                     PMAPPROG, PMAPVERS,
+                                     &socket,
                                      RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
                break;
        }
@@ -307,8 +356,7 @@ static unsigned short getport(struct sockaddr_in *saddr,
                else if (port == 0)
                        rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
        }
-       if (socket != 1)
-               close(socket);
+       close(socket);
 
        return port;
 }
@@ -333,7 +381,6 @@ static int probe_port(clnt_addr_t *server, const unsigned long *versions,
        p_vers = vers ? &vers : versions;
        rpc_createerr.cf_stat = 0;
        for (;;) {
-               saddr->sin_port = htons(PMAPPORT);
                p_port = getport(saddr, prog, *p_vers, *p_prot);
                if (p_port) {
                        if (!port || port == p_port) {
@@ -345,7 +392,7 @@ static int probe_port(clnt_addr_t *server, const unsigned long *versions,
                                                inet_ntoa(saddr->sin_addr),
                                                prog, *p_vers,
                                                *p_prot == IPPROTO_UDP ?
-                                                       "udp" : "tcp",
+                                                       _("UDP") : _("TCP"),
                                                p_port);
                                 }
                                if (clnt_ping(saddr, prog, *p_vers, *p_prot, NULL))
@@ -553,7 +600,8 @@ CLIENT *mnt_openclnt(clnt_addr_t *mnt_server, int *msock)
        CLIENT *clnt = NULL;
 
        mnt_saddr->sin_port = htons((u_short)mnt_pmap->pm_port);
-       *msock = get_socket(mnt_saddr, mnt_pmap->pm_prot, TRUE, FALSE);
+       *msock = get_socket(mnt_saddr, mnt_pmap->pm_prot, MOUNT_TIMEOUT,
+                               TRUE, FALSE);
        if (*msock == RPC_ANYSOCK) {
                if (rpc_createerr.cf_error.re_errno == EADDRINUSE)
                        /*
@@ -608,10 +656,10 @@ int clnt_ping(struct sockaddr_in *saddr, const unsigned long prog,
        static char clnt_res;
        struct sockaddr dissolve;
 
-       rpc_createerr.cf_stat = stat = errno = 0;
-       sock = get_socket(saddr, prot, FALSE, TRUE);
+       rpc_createerr.cf_stat = stat = 0;
+       sock = get_socket(saddr, prot, CONNECT_TIMEOUT, FALSE, TRUE);
        if (sock == RPC_ANYSOCK) {
-               if (errno == ETIMEDOUT) {
+               if (rpc_createerr.cf_error.re_errno == ETIMEDOUT) {
                        /*
                         * TCP timeout. Bubble up the error to see 
                         * how it should be handled.