]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/gssd/gssd_proc.c
nfs-utils: query for remote port using rpcbind instead of getaddrinfo
[nfs-utils.git] / utils / gssd / gssd_proc.c
index 6a68cdf6d1744fb19f57bc4a0b22ee82d2c1b5f0..4efc088fc02d44061a9c4a83184f05508b7e3989 100644 (file)
@@ -72,6 +72,7 @@
 #include "gss_util.h"
 #include "krb5_util.h"
 #include "context.h"
+#include "nfsrpc.h"
 
 /*
  * pollarray:
@@ -540,6 +541,74 @@ out_err:
        return -1;
 }
 
+/*
+ * If the port isn't already set, do an rpcbind query to the remote server
+ * using the program and version and get the port. 
+ *
+ * Newer kernels send the value of the port= mount option in the "info"
+ * file for the upcall or '0' for NFSv2/3. For NFSv4 it sends the value
+ * of the port= option or '2049'. The port field in a new sockaddr should
+ * reflect the value that was sent by the kernel.
+ */
+static int
+populate_port(struct sockaddr *sa, const socklen_t salen,
+             const rpcprog_t program, const rpcvers_t version,
+             const unsigned short protocol)
+{
+       struct sockaddr_in      *s4 = (struct sockaddr_in *) sa;
+       unsigned short          port;
+
+       /*
+        * Newer kernels send the port in the upcall. If we already have
+        * the port, there's no need to look it up.
+        */
+       switch (sa->sa_family) {
+       case AF_INET:
+               if (s4->sin_port != 0) {
+                       printerr(2, "DEBUG: port already set to %d\n",
+                                ntohs(s4->sin_port));
+                       return 1;
+               }
+               break;
+       default:
+               printerr(0, "ERROR: unsupported address family %d\n",
+                           sa->sa_family);
+               return 0;
+       }
+
+       /*
+        * Newer kernels that send the port in the upcall set the value to
+        * 2049 for NFSv4 mounts when one isn't specified. The check below is
+        * only for kernels that don't send the port in the upcall. For those
+        * we either have to do an rpcbind query or set it to the standard
+        * port. Doing a query could be problematic (firewalls, etc), so take
+        * the latter approach.
+        */
+       if (program == 100003 && version == 4) {
+               port = 2049;
+               goto set_port;
+       }
+
+       port = nfs_getport(sa, salen, program, version, protocol);
+       if (!port) {
+               printerr(0, "ERROR: unable to obtain port for prog %ld "
+                           "vers %ld\n", program, version);
+               return 0;
+       }
+
+set_port:
+       printerr(2, "DEBUG: setting port to %hu for prog %lu vers %lu\n", port,
+                program, version);
+
+       switch (sa->sa_family) {
+       case AF_INET:
+               s4->sin_port = htons(port);
+               break;
+       }
+
+       return 1;
+}
+
 /*
  * Create an RPC connection and establish an authenticated
  * gss context with a server.
@@ -555,15 +624,13 @@ int create_auth_rpc_client(struct clnt_info *clp,
        AUTH                    *auth = NULL;
        uid_t                   save_uid = -1;
        int                     retval = -1;
-       int                     errcode;
        OM_uint32               min_stat;
        char                    rpc_errmsg[1024];
        int                     sockp = RPC_ANYSOCK;
        int                     sendsz = 32768, recvsz = 32768;
-       struct addrinfo         ai_hints, *a = NULL;
-       char                    service[64];
-       char                    *at_sign;
-       struct sockaddr_in      *addr = (struct sockaddr_in *) &clp->addr;
+       int                     protocol;
+       struct sockaddr         *addr = (struct sockaddr *) &clp->addr;
+       socklen_t               salen;
 
        /* Create the context as the user (not as root) */
        save_uid = geteuid();
@@ -617,15 +684,10 @@ int create_auth_rpc_client(struct clnt_info *clp,
        printerr(2, "creating %s client for server %s\n", clp->protocol,
                        clp->servername);
 
-       memset(&ai_hints, '\0', sizeof(ai_hints));
-       ai_hints.ai_family = PF_INET;
-       ai_hints.ai_flags |= AI_CANONNAME;
        if ((strcmp(clp->protocol, "tcp")) == 0) {
-               ai_hints.ai_socktype = SOCK_STREAM;
-               ai_hints.ai_protocol = IPPROTO_TCP;
+               protocol = IPPROTO_TCP;
        } else if ((strcmp(clp->protocol, "udp")) == 0) {
-               ai_hints.ai_socktype = SOCK_DGRAM;
-               ai_hints.ai_protocol = IPPROTO_UDP;
+               protocol = IPPROTO_UDP;
        } else {
                printerr(0, "WARNING: unrecognized protocol, '%s', requested "
                         "for connection to server %s for user with uid %d\n",
@@ -633,40 +695,22 @@ int create_auth_rpc_client(struct clnt_info *clp,
                goto out_fail;
        }
 
-       /* extract the service name from clp->servicename */
-       if ((at_sign = strchr(clp->servicename, '@')) == NULL) {
-               printerr(0, "WARNING: servicename (%s) not formatted as "
-                       "expected with service@host\n", clp->servicename);
-               goto out_fail;
-       }
-       if ((at_sign - clp->servicename) >= sizeof(service)) {
-               printerr(0, "WARNING: service portion of servicename (%s) "
-                       "is too long!\n", clp->servicename);
-               goto out_fail;
-       }
-       strncpy(service, clp->servicename, at_sign - clp->servicename);
-       service[at_sign - clp->servicename] = '\0';
-
-       errcode = getaddrinfo(clp->servername, service, &ai_hints, &a);
-       if (errcode) {
-               printerr(0, "WARNING: Error from getaddrinfo for server "
-                        "'%s': %s\n", clp->servername, gai_strerror(errcode));
+       switch (addr->sa_family) {
+       case AF_INET:
+               salen = sizeof(struct sockaddr_in);
+               break;
+       default:
+               printerr(1, "ERROR: Unknown address family %d\n",
+                        addr->sa_family);
                goto out_fail;
        }
 
-       if (a == NULL) {
-               printerr(0, "WARNING: No address information found for "
-                        "connection to server %s for user with uid %d\n",
-                        clp->servername, uid);
+       if (!populate_port(addr, salen, clp->prog, clp->vers, protocol))
                goto out_fail;
-       }
-
-       if (addr->sin_port != 0)
-               ((struct sockaddr_in *) a->ai_addr)->sin_port = addr->sin_port;
 
-       if (a->ai_protocol == IPPROTO_TCP) {
+       if (protocol == IPPROTO_TCP) {
                if ((rpc_clnt = clnttcp_create(
-                                       (struct sockaddr_in *) a->ai_addr,
+                                       (struct sockaddr_in *) addr,
                                        clp->prog, clp->vers, &sockp,
                                        sendsz, recvsz)) == NULL) {
                        snprintf(rpc_errmsg, sizeof(rpc_errmsg),
@@ -677,10 +721,10 @@ int create_auth_rpc_client(struct clnt_info *clp,
                                 clnt_spcreateerror(rpc_errmsg));
                        goto out_fail;
                }
-       } else if (a->ai_protocol == IPPROTO_UDP) {
+       } else if (protocol == IPPROTO_UDP) {
                const struct timeval timeout = {5, 0};
                if ((rpc_clnt = clntudp_bufcreate(
-                                       (struct sockaddr_in *) a->ai_addr,
+                                       (struct sockaddr_in *) addr,
                                        clp->prog, clp->vers, timeout,
                                        &sockp, sendsz, recvsz)) == NULL) {
                        snprintf(rpc_errmsg, sizeof(rpc_errmsg),
@@ -691,16 +735,7 @@ int create_auth_rpc_client(struct clnt_info *clp,
                                 clnt_spcreateerror(rpc_errmsg));
                        goto out_fail;
                }
-       } else {
-               /* Shouldn't happen! */
-               printerr(0, "ERROR: requested protocol '%s', but "
-                        "got addrinfo with protocol %d\n",
-                        clp->protocol, a->ai_protocol);
-               goto out_fail;
        }
-       /* We're done with this */
-       freeaddrinfo(a);
-       a = NULL;
 
        printerr(2, "creating context with server %s\n", clp->servicename);
        auth = authgss_create_default(rpc_clnt, clp->servicename, &sec);
@@ -722,7 +757,6 @@ int create_auth_rpc_client(struct clnt_info *clp,
   out:
        if (sec.cred != GSS_C_NO_CREDENTIAL)
                gss_release_cred(&min_stat, &sec.cred);
-       if (a != NULL) freeaddrinfo(a);
        /* Restore euid to original value */
        if ((save_uid != -1) && (setfsuid(save_uid) != uid)) {
                printerr(0, "WARNING: Failed to restore fsuid"