Merge branch 'master' of git+ssh://gnunet.org/gnunet

[oweals/gnunet.git] / src / gns / nss / nss_gns_query.c

diff --git a/src/gns/nss/nss_gns_query.c b/src/gns/nss/nss_gns_query.c
index ba9fa149672fa948ae3ac457ecaa1f722032da2c..380788d35d0cea3a761cbd87db8781edf050e26d 100644 (file)
--- a/src/gns/nss/nss_gns_query.c
+++ b/src/gns/nss/nss_gns_query.c
@@ -1,55 +1,162 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2012 GNUnet e.V.
+
+     GNUnet is free software: you can redistribute it and/or modify it
+     under the terms of the GNU Affero General Public License as published
+     by the Free Software Foundation, either version 3 of the License,
+     or (at your option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     Affero General Public License for more details.
+
+     You should have received a copy of the GNU Affero General Public License
+     along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+     SPDX-License-Identifier: AGPL3.0-or-later
+*/
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include "nss_gns_query.h"
 #include <arpa/inet.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include <unistd.h>
+#include <signal.h>
 
-int gns_resolve_name(int af, const char *name, struct userdata *u)
+
+static void
+kwait (pid_t chld)
+{
+  int ret;
+
+  kill (chld, SIGKILL);
+  waitpid (chld,
+           &ret,
+           0);
+}
+
+
+/**
+ * Wrapper function that uses gnunet-gns cli tool to resolve
+ * an IPv4/6 address.
+ *
+ * @param af address family
+ * @param name the name to resolve
+ * @param u the userdata (result struct)
+ * @return -1 on internal error,
+ *         -2 if request is not for GNS,
+ *         -3 on timeout,
+ *          else 0
+ */
+int
+gns_resolve_name (int af,
+                 const char *name,
+                 struct userdata *u)
 {
   FILE *p;
-  char *cmd;
   char line[128];
+  int ret;
+  int out[2];
+  pid_t pid;
 
-  if (af == AF_INET6)
+  if (0 != pipe (out))
+    return -1;
+  pid = fork ();
+  if (-1 == pid)
+    return -1;
+  if (0 == pid)
   {
-    if (-1 == asprintf(&cmd, "%s -t AAAA -u %s\n", "gnunet-gns -r", name))
-      return -1;
+    char *argv[] = {
+      "gnunet-gns",
+      "-r",
+      "-t",
+      (AF_INET6 == af) ? "AAAA" : "A",
+      "-u",
+      (char *) name,
+      NULL
+    };
+
+    (void) close (STDOUT_FILENO);
+    if ( (0 != close (out[0])) ||
+         (STDOUT_FILENO != dup2 (out[1], STDOUT_FILENO)) )
+      _exit (1);
+    (void) execvp ("gnunet-gns",
+                   argv);
+    _exit (1);
   }
-  else
-  {
-    if (-1 == asprintf(&cmd, "%s %s\n", "gnunet-gns -r -u", name))
+  (void) close (out[1]);
+  p = fdopen (out[0], "r");
+  if (NULL == p)
+    {
+      kwait (pid);
       return -1;
-  }
-
-  p = popen(cmd,"r");
-
-  if (p != NULL )
+    }
+  while (NULL != fgets (line,
+                        sizeof (line),
+                        p))
   {
-    while (fgets( line, sizeof(line), p ) != NULL)
+    if (u->count >= MAX_ENTRIES)
+      break;
+    if (line[strlen(line)-1] == '\n')
     {
-
-      if (u->count >= MAX_ENTRIES)
-        break;
-
-      if (line[strlen(line)-1] == '\n')
+      line[strlen(line)-1] = '\0';
+      if (AF_INET == af)
       {
-        line[strlen(line)-1] = '\0';
-        if (af == AF_INET)
+       if (inet_pton(af,
+                      line,
+                      &u->data.ipv4[u->count]))
         {
-          inet_pton(af, line, &(u->data.ipv4[u->count++]));
-          u->data_len += sizeof(ipv4_address_t);
-        }
-        else if ((af == AF_INET6))
+         u->count++;
+         u->data_len += sizeof(ipv4_address_t);
+       }
+       else
+       {
+         (void) fclose (p);
+          kwait (pid);
+         errno = EINVAL;
+         return -1;
+       }
+      }
+      else if (AF_INET6 == af)
+      {
+       if (inet_pton(af,
+                      line,
+                      &u->data.ipv6[u->count]))
+        {
+         u->count++;
+         u->data_len += sizeof(ipv6_address_t);
+       }
+       else
         {
-          inet_pton(af, line, &(u->data.ipv6[u->count++]));
-          u->data_len += sizeof(ipv6_address_t);
-        }
+         (void) fclose (p);
+          kwait (pid);
+         errno = EINVAL;
+         return -1;
+       }
       }
     }
   }
-  fclose(p);
-  free(cmd);
-
+  (void) fclose (p);
+  waitpid (pid,
+           &ret,
+           0);
+  if (! WIFEXITED (ret))
+    return -1;
+  if (4 == WEXITSTATUS (ret))
+    return -2; /* not for GNS */
+  if (3 == ret)
+    return -3; /* timeout -> not found */
+  if ( (2 == WEXITSTATUS (ret)) ||
+       (1 == WEXITSTATUS (ret)) )
+    return -2; /* launch failure -> service unavailable */
   return 0;
-
 }
+
+/* end of nss_gns_query.c */