Introduce a new DNS resolver function in utils/mount/network.c that uses

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

diff --git a/utils/mount/network.c b/utils/mount/network.c
index 49d3c6b26d63c33c4b83ae6f497e1fb2a809f87f..30a4d40ef78c7216e149e6cd58a0dc7685d05bfb 100644 (file)
--- a/utils/mount/network.c
+++ b/utils/mount/network.c
@@ -21,6 +21,10 @@
  *
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <ctype.h>
 #include <unistd.h>
 #include <stdio.h>
@@ -139,6 +143,60 @@ static const unsigned long probe_mnt3_first[] = {
        0,
 };
 
+/**
+ * nfs_name_to_address - resolve hostname to an IPv4 or IPv6 socket address
+ * @hostname: pointer to C string containing DNS hostname to resolve
+ * @sap: pointer to buffer to fill with socket address
+ * @len: IN: size of buffer to fill; OUT: size of socket address
+ *
+ * Returns 1 and places a socket address at @sap if successful;
+ * otherwise zero.
+ */
+int nfs_name_to_address(const char *hostname,
+                       const sa_family_t af_hint,
+                       struct sockaddr *sap, socklen_t *salen)
+{
+       struct addrinfo *gai_results;
+       struct addrinfo gai_hint = {
+               .ai_family      = af_hint,
+               .ai_flags       = AI_ADDRCONFIG,
+       };
+       socklen_t len = *salen;
+       int error, ret = 0;
+
+       if (af_hint == AF_INET6)
+               gai_hint.ai_flags |= AI_V4MAPPED|AI_ALL;
+
+       *salen = 0;
+
+       error = getaddrinfo(hostname, NULL, &gai_hint, &gai_results);
+       if (error) {
+               nfs_error(_("%s: DNS resolution failed for %s: %s"),
+                       progname, hostname, (error == EAI_SYSTEM ?
+                               strerror(errno) : gai_strerror(error)));
+               return ret;
+       }
+
+       switch (gai_results->ai_addr->sa_family) {
+       case AF_INET:
+       case AF_INET6:
+               if (len >= gai_results->ai_addrlen) {
+                       *salen = gai_results->ai_addrlen;
+                       memcpy(sap, gai_results->ai_addr, *salen);
+                       ret = 1;
+               }
+               break;
+       default:
+               /* things are really broken if we get here, so warn */
+               nfs_error(_("%s: unrecognized DNS resolution results for %s"),
+                               progname, hostname);
+               break;
+       }
+
+       freeaddrinfo(gai_results);
+       return ret;
+}
+
 /**
  * nfs_gethostbyname - resolve a hostname to an IPv4 address
  * @hostname: pointer to a C string containing a DNS hostname
@@ -146,26 +204,12 @@ static const unsigned long probe_mnt3_first[] = {
  *
  * Returns 1 if successful, otherwise zero.
  */
-int nfs_gethostbyname(const char *hostname, struct sockaddr_in *saddr)
+int nfs_gethostbyname(const char *hostname, struct sockaddr_in *sin)
 {
-       struct hostent *hp;
-
-       saddr->sin_family = AF_INET;
-       if (!inet_aton(hostname, &saddr->sin_addr)) {
-               if ((hp = gethostbyname(hostname)) == NULL) {
-                       nfs_error(_("%s: can't get address for %s\n"),
-                                       progname, hostname);
-                       return 0;
-               } else {
-                       if (hp->h_length > sizeof(*saddr)) {
-                               nfs_error(_("%s: got bad hp->h_length\n"),
-                                               progname);
-                               hp->h_length = sizeof(*saddr);
-                       }
-                       memcpy(&saddr->sin_addr, hp->h_addr, hp->h_length);
-               }
-       }
-       return 1;
+       socklen_t len = sizeof(*sin);
+
+       return nfs_name_to_address(hostname, AF_INET,
+                                       (struct sockaddr *)sin, &len);
 }
 
 /*
@@ -408,7 +452,8 @@ static int probe_port(clnt_addr_t *server, const unsigned long *versions,
                                        goto out_bad;
                        }
                }
-               if (rpc_createerr.cf_stat != RPC_PROGNOTREGISTERED)
+               if (rpc_createerr.cf_stat != RPC_PROGNOTREGISTERED &&
+                   rpc_createerr.cf_stat != RPC_PROGVERSMISMATCH)
                        goto out_bad;
 
                if (!prot) {
@@ -416,10 +461,6 @@ static int probe_port(clnt_addr_t *server, const unsigned long *versions,
                                continue;
                        p_prot = protos;
                }
-               if (vers == pmap->pm_vers) {
-                       p_vers = versions;
-                       vers = 0;
-               }
                if (vers || !*++p_vers)
                        break;
        }
@@ -497,7 +538,7 @@ int probe_bothports(clnt_addr_t *mnt_server, clnt_addr_t *nfs_server)
        for (; *probe_vers; probe_vers++) {
                nfs_pmap->pm_vers = mntvers_to_nfs(*probe_vers);
                if ((res = probe_nfsport(nfs_server) != 0)) {
-                       mnt_pmap->pm_vers = nfsvers_to_mnt(nfs_pmap->pm_vers);
+                       mnt_pmap->pm_vers = *probe_vers;
                        if ((res = probe_mntport(mnt_server)) != 0)
                                return 1;
                        memcpy(mnt_pmap, &save_mnt, sizeof(*mnt_pmap));
@@ -585,27 +626,16 @@ int nfs_call_umount(clnt_addr_t *mnt_server, dirpath *argp)
        enum clnt_stat res = 0;
        int msock;
 
-       switch (mnt_server->pmap.pm_vers) {
-       case 3:
-       case 2:
-       case 1:
-               if (!probe_mntport(mnt_server))
-                       return 0;
-               clnt = mnt_openclnt(mnt_server, &msock);
-               if (!clnt)
-                       return 0;
-               res = clnt_call(clnt, MOUNTPROC_UMNT,
-                               (xdrproc_t)xdr_dirpath, (caddr_t)argp,
-                               (xdrproc_t)xdr_void, NULL,
-                               TIMEOUT);
-               mnt_closeclnt(clnt, msock);
-               if (res == RPC_SUCCESS)
-                       return 1;
-               break;
-       default:
-               res = RPC_SUCCESS;
-               break;
-       }
+       if (!probe_mntport(mnt_server))
+               return 0;
+       clnt = mnt_openclnt(mnt_server, &msock);
+       if (!clnt)
+               return 0;
+       res = clnt_call(clnt, MOUNTPROC_UMNT,
+                       (xdrproc_t)xdr_dirpath, (caddr_t)argp,
+                       (xdrproc_t)xdr_void, NULL,
+                       TIMEOUT);
+       mnt_closeclnt(clnt, msock);
 
        if (res == RPC_SUCCESS)
                return 1;