getnameinfo: Refactor and fix memory leak [BZ #19642]
authorFlorian Weimer <fweimer@redhat.com>
Fri, 29 Apr 2016 15:08:06 +0000 (17:08 +0200)
committerFlorian Weimer <fweimer@redhat.com>
Fri, 29 Apr 2016 15:08:06 +0000 (17:08 +0200)
Split getnameinfo into separate functions for host and service
lookups, and for different address families.

ChangeLog
inet/getnameinfo.c

index 5f8424a..ca96f09 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2016-04-29  Florian Weimer  <fweimer@redhat.com>
+
+       [BZ #19642]
+       * inet/getnameinfo.c (gni_host_inet_name, gni_host_inet_numeric)
+       (gni_host_inet, gni_host_local, gni_host, gni_serv_inet)
+       (gni_serv_local, gni_serv): New functions extracted from
+       getnameinfo.
+       (getnameinfo): Call gni_host and gni_serv to perform the
+       processing.  Always free scratch buffer.
+
 2016-04-29  Gabriel F. T. Gomes  <gftg@linux.vnet.ibm.com>
 
        * sysdeps/powerpc/powerpc64/power8/strncpy.S: Call memset to pad the
index 9b1847b..ce05dda 100644 (file)
@@ -1,3 +1,21 @@
+/* Convert socket address to string using Name Service Switch modules.
+   Copyright (C) 1997-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
 /* The Inner Net License, Version 2.00
 
   The author(s) grant permission for redistribution and use in source and
@@ -169,19 +187,323 @@ nrl_domainname (void)
   return domain;
 };
 
+/* Convert host name, AF_INET/AF_INET6 case, name only.  */
+static int
+gni_host_inet_name (struct scratch_buffer *tmpbuf,
+                   const struct sockaddr *sa, socklen_t addrlen,
+                   char *host, socklen_t hostlen, int flags)
+{
+  int herrno;
+  struct hostent th;
+  struct hostent *h = NULL;
+  if (sa->sa_family == AF_INET6)
+    {
+      while (__gethostbyaddr_r ((const void *) &(((const struct sockaddr_in6 *) sa)->sin6_addr),
+                               sizeof(struct in6_addr),
+                               AF_INET6, &th,
+                               tmpbuf->data, tmpbuf->length,
+                               &h, &herrno))
+       if (herrno == NETDB_INTERNAL && errno == ERANGE)
+         {
+           if (!scratch_buffer_grow (tmpbuf))
+             {
+               __set_h_errno (herrno);
+               return EAI_MEMORY;
+             }
+         }
+       else
+         break;
+    }
+  else
+    {
+      while (__gethostbyaddr_r ((const void *) &(((const struct sockaddr_in *)sa)->sin_addr),
+                               sizeof(struct in_addr),
+                               AF_INET, &th,
+                               tmpbuf->data, tmpbuf->length,
+                               &h, &herrno))
+       if (herrno == NETDB_INTERNAL && errno == ERANGE)
+           {
+             if (!scratch_buffer_grow (tmpbuf))
+               {
+                 __set_h_errno (herrno);
+                 return EAI_MEMORY;
+               }
+           }
+       else
+         break;
+    }
+
+  if (h == NULL)
+    {
+      if (herrno == NETDB_INTERNAL)
+       {
+         __set_h_errno (herrno);
+         return EAI_SYSTEM;
+       }
+      if (herrno == TRY_AGAIN)
+       {
+         __set_h_errno (herrno);
+         return EAI_AGAIN;
+       }
+    }
+
+  if (h)
+    {
+      char *c;
+      if ((flags & NI_NOFQDN)
+         && (c = nrl_domainname ())
+         && (c = strstr (h->h_name, c))
+         && (c != h->h_name) && (*(--c) == '.'))
+       /* Terminate the string after the prefix.  */
+       *c = '\0';
+
+#ifdef HAVE_LIBIDN
+      /* If requested, convert from the IDN format.  */
+      if (flags & NI_IDN)
+       {
+         int idn_flags = 0;
+         if  (flags & NI_IDN_ALLOW_UNASSIGNED)
+           idn_flags |= IDNA_ALLOW_UNASSIGNED;
+         if (flags & NI_IDN_USE_STD3_ASCII_RULES)
+           idn_flags |= IDNA_USE_STD3_ASCII_RULES;
+
+         char *out;
+         int rc = __idna_to_unicode_lzlz (h->h_name, &out,
+                                          idn_flags);
+         if (rc != IDNA_SUCCESS)
+           {
+             if (rc == IDNA_MALLOC_ERROR)
+               return EAI_MEMORY;
+             if (rc == IDNA_DLOPEN_ERROR)
+               return EAI_SYSTEM;
+             return EAI_IDN_ENCODE;
+           }
+
+         if (out != h->h_name)
+           {
+             h->h_name = strdupa (out);
+             free (out);
+           }
+       }
+#endif
+
+      size_t len = strlen (h->h_name) + 1;
+      if (len > hostlen)
+       return EAI_OVERFLOW;
+
+      memcpy (host, h->h_name, len);
+
+      return 0;
+    }
+
+  return EAI_NONAME;
+}
+
+/* Convert host name, AF_INET/AF_INET6 case, numeric conversion.  */
+static int
+gni_host_inet_numeric (struct scratch_buffer *tmpbuf,
+                      const struct sockaddr *sa, socklen_t addrlen,
+                      char *host, socklen_t hostlen, int flags)
+{
+  const char *c;
+  if (sa->sa_family == AF_INET6)
+    {
+      const struct sockaddr_in6 *sin6p;
+      uint32_t scopeid;
+
+      sin6p = (const struct sockaddr_in6 *) sa;
+
+      c = inet_ntop (AF_INET6,
+                    (const void *) &sin6p->sin6_addr, host, hostlen);
+      scopeid = sin6p->sin6_scope_id;
+      if (scopeid != 0)
+       {
+         /* Buffer is >= IFNAMSIZ+1.  */
+         char scopebuf[IFNAMSIZ + 1];
+         char *scopeptr;
+         int ni_numericscope = 0;
+         size_t real_hostlen = __strnlen (host, hostlen);
+         size_t scopelen = 0;
+
+         scopebuf[0] = SCOPE_DELIMITER;
+         scopebuf[1] = '\0';
+         scopeptr = &scopebuf[1];
+
+         if (IN6_IS_ADDR_LINKLOCAL (&sin6p->sin6_addr)
+             || IN6_IS_ADDR_MC_LINKLOCAL (&sin6p->sin6_addr))
+           {
+             if (if_indextoname (scopeid, scopeptr) == NULL)
+               ++ni_numericscope;
+             else
+               scopelen = strlen (scopebuf);
+           }
+         else
+           ++ni_numericscope;
+
+         if (ni_numericscope)
+           scopelen = 1 + __snprintf (scopeptr,
+                                      (scopebuf
+                                       + sizeof scopebuf
+                                       - scopeptr),
+                                      "%u", scopeid);
+
+         if (real_hostlen + scopelen + 1 > hostlen)
+           /* Signal the buffer is too small.  This is
+              what inet_ntop does.  */
+           c = NULL;
+         else
+           memcpy (host + real_hostlen, scopebuf, scopelen + 1);
+       }
+    }
+  else
+    c = inet_ntop (AF_INET,
+                  (const void *) &(((const struct sockaddr_in *) sa)->sin_addr),
+                  host, hostlen);
+  if (c == NULL)
+    return EAI_OVERFLOW;
+  return 0;
+}
+
+static int
+gni_host_inet (struct scratch_buffer *tmpbuf,
+              const struct sockaddr *sa, socklen_t addrlen,
+              char *host, socklen_t hostlen, int flags)
+{
+  if (!(flags & NI_NUMERICHOST))
+    {
+      int result = gni_host_inet_name
+       (tmpbuf, sa, addrlen, host, hostlen, flags);
+      if (result != EAI_NONAME)
+       return result;
+    }
+
+  if (flags & NI_NAMEREQD)
+    return EAI_NONAME;
+  else
+    return gni_host_inet_numeric
+      (tmpbuf, sa, addrlen, host, hostlen, flags);
+}
+
+static int
+gni_host_local (struct scratch_buffer *tmpbuf,
+               const struct sockaddr *sa, socklen_t addrlen,
+               char *host, socklen_t hostlen, int flags)
+{
+
+  if (!(flags & NI_NUMERICHOST))
+    {
+      struct utsname utsname;
+
+      if (!uname (&utsname))
+       {
+         strncpy (host, utsname.nodename, hostlen);
+         return 0;
+       }
+    }
+
+  if (flags & NI_NAMEREQD)
+    return EAI_NONAME;
+
+  strncpy (host, "localhost", hostlen);
+  return 0;
+}
+
+static int
+gni_host (struct scratch_buffer *tmpbuf,
+         const struct sockaddr *sa, socklen_t addrlen,
+         char *host, socklen_t hostlen, int flags)
+{
+  switch (sa->sa_family)
+    {
+    case AF_INET:
+    case AF_INET6:
+      return gni_host_inet (tmpbuf, sa, addrlen, host, hostlen, flags);
+
+    case AF_LOCAL:
+      return gni_host_local (tmpbuf, sa, addrlen, host, hostlen, flags);
+
+    default:
+      return EAI_FAMILY;
+    }
+}
+
+/* Convert service to string, AF_INET and AF_INET6 variant.  */
+static int
+gni_serv_inet (struct scratch_buffer *tmpbuf,
+              const struct sockaddr *sa, socklen_t addrlen,
+              char *serv, socklen_t servlen, int flags)
+{
+  _Static_assert
+    (offsetof (struct sockaddr_in, sin_port)
+     == offsetof (struct sockaddr_in6, sin6_port)
+     && sizeof (((struct sockaddr_in) {}).sin_port) == sizeof (in_port_t)
+     && sizeof (((struct sockaddr_in6) {}).sin6_port) == sizeof (in_port_t),
+     "AF_INET and AF_INET6 port consistency");
+  if (!(flags & NI_NUMERICSERV))
+    {
+      struct servent *s, ts;
+      int e;
+      while ((e = __getservbyport_r (((const struct sockaddr_in *) sa)->sin_port,
+                                    ((flags & NI_DGRAM)
+                                     ? "udp" : "tcp"), &ts,
+                                    tmpbuf->data, tmpbuf->length, &s)))
+       {
+         if (e == ERANGE)
+           {
+             if (!scratch_buffer_grow (tmpbuf))
+               return EAI_MEMORY;
+           }
+         else
+           break;
+       }
+      if (s)
+       {
+         strncpy (serv, s->s_name, servlen);
+         return 0;
+       }
+      /* Fall through to numeric conversion.  */
+    }
+  if (__snprintf (serv, servlen, "%d",
+                 ntohs (((const struct sockaddr_in *) sa)->sin_port))
+      + 1 > servlen)
+      return EAI_OVERFLOW;
+  return 0;
+}
+
+/* Convert service to string, AF_LOCAL variant.  */
+static int
+gni_serv_local (struct scratch_buffer *tmpbuf,
+              const struct sockaddr *sa, socklen_t addrlen,
+              char *serv, socklen_t servlen, int flags)
+{
+  strncpy (serv, ((const struct sockaddr_un *) sa)->sun_path, servlen);
+  return 0;
+}
+
+/* Convert service to string, dispatching to the implementations
+   above.  */
+static int
+gni_serv (struct scratch_buffer *tmpbuf,
+         const struct sockaddr *sa, socklen_t addrlen,
+         char *serv, socklen_t servlen, int flags)
+{
+  switch (sa->sa_family)
+    {
+    case AF_INET:
+    case AF_INET6:
+      return gni_serv_inet (tmpbuf, sa, addrlen, serv, servlen, flags);
+    case AF_LOCAL:
+      return gni_serv_local (tmpbuf, sa, addrlen, serv, servlen, flags);
+    default:
+      return EAI_FAMILY;
+    }
+}
 
 int
 getnameinfo (const struct sockaddr *sa, socklen_t addrlen, char *host,
             socklen_t hostlen, char *serv, socklen_t servlen,
             int flags)
 {
-  int herrno;
-  struct hostent th;
-  int ok = 0;
-  struct scratch_buffer tmpbuf;
-
-  scratch_buffer_init (&tmpbuf);
-
   if (flags & ~(NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|NI_DGRAM
 #ifdef HAVE_LIBIDN
                |NI_IDN|NI_IDN_ALLOW_UNASSIGNED|NI_IDN_USE_STD3_ASCII_RULES
@@ -213,249 +535,34 @@ getnameinfo (const struct sockaddr *sa, socklen_t addrlen, char *host,
       return EAI_FAMILY;
     }
 
-  if (host != NULL && hostlen > 0)
-    switch (sa->sa_family)
-      {
-      case AF_INET:
-      case AF_INET6:
-       if (!(flags & NI_NUMERICHOST))
-         {
-           struct hostent *h = NULL;
-           if (sa->sa_family == AF_INET6)
-             {
-               while (__gethostbyaddr_r ((const void *) &(((const struct sockaddr_in6 *) sa)->sin6_addr),
-                                         sizeof(struct in6_addr),
-                                         AF_INET6, &th,
-                                         tmpbuf.data, tmpbuf.length,
-                                         &h, &herrno))
-                 if (herrno == NETDB_INTERNAL && errno == ERANGE)
-                   {
-                     if (!scratch_buffer_grow (&tmpbuf))
-                       {
-                         __set_h_errno (herrno);
-                         return EAI_MEMORY;
-                       }
-                   }
-                 else
-                   break;
-             }
-           else
-             {
-               while (__gethostbyaddr_r ((const void *) &(((const struct sockaddr_in *)sa)->sin_addr),
-                                         sizeof(struct in_addr),
-                                         AF_INET, &th,
-                                         tmpbuf.data, tmpbuf.length,
-                                         &h, &herrno))
-                 if (herrno == NETDB_INTERNAL && errno == ERANGE)
-                   {
-                     if (!scratch_buffer_grow (&tmpbuf))
-                       {
-                         __set_h_errno (herrno);
-                         return EAI_MEMORY;
-                       }
-                   }
-                 else
-                   break;
-             }
-
-           if (h == NULL)
-             {
-               if (herrno == NETDB_INTERNAL)
-                 {
-                   __set_h_errno (herrno);
-                   return EAI_SYSTEM;
-                 }
-               if (herrno == TRY_AGAIN)
-                 {
-                   __set_h_errno (herrno);
-                   return EAI_AGAIN;
-                 }
-             }
-
-           if (h)
-             {
-               char *c;
-               if ((flags & NI_NOFQDN)
-                   && (c = nrl_domainname ())
-                   && (c = strstr (h->h_name, c))
-                   && (c != h->h_name) && (*(--c) == '.'))
-                 /* Terminate the string after the prefix.  */
-                 *c = '\0';
-
-#ifdef HAVE_LIBIDN
-               /* If requested, convert from the IDN format.  */
-               if (flags & NI_IDN)
-                 {
-                   int idn_flags = 0;
-                   if  (flags & NI_IDN_ALLOW_UNASSIGNED)
-                     idn_flags |= IDNA_ALLOW_UNASSIGNED;
-                   if (flags & NI_IDN_USE_STD3_ASCII_RULES)
-                     idn_flags |= IDNA_USE_STD3_ASCII_RULES;
-
-                   char *out;
-                   int rc = __idna_to_unicode_lzlz (h->h_name, &out,
-                                                    idn_flags);
-                   if (rc != IDNA_SUCCESS)
-                     {
-                       if (rc == IDNA_MALLOC_ERROR)
-                         return EAI_MEMORY;
-                       if (rc == IDNA_DLOPEN_ERROR)
-                         return EAI_SYSTEM;
-                       return EAI_IDN_ENCODE;
-                     }
-
-                   if (out != h->h_name)
-                     {
-                       h->h_name = strdupa (out);
-                       free (out);
-                     }
-                 }
-#endif
-
-               size_t len = strlen (h->h_name) + 1;
-               if (len > hostlen)
-                 return EAI_OVERFLOW;
-
-               memcpy (host, h->h_name, len);
-
-               ok = 1;
-             }
-         }
-
-       if (!ok)
-         {
-           if (flags & NI_NAMEREQD)
-             return EAI_NONAME;
-           else
-             {
-               const char *c;
-               if (sa->sa_family == AF_INET6)
-                 {
-                   const struct sockaddr_in6 *sin6p;
-                   uint32_t scopeid;
-
-                   sin6p = (const struct sockaddr_in6 *) sa;
-
-                   c = inet_ntop (AF_INET6,
-                                  (const void *) &sin6p->sin6_addr, host, hostlen);
-                   scopeid = sin6p->sin6_scope_id;
-                   if (scopeid != 0)
-                     {
-                       /* Buffer is >= IFNAMSIZ+1.  */
-                       char scopebuf[IFNAMSIZ + 1];
-                       char *scopeptr;
-                       int ni_numericscope = 0;
-                       size_t real_hostlen = __strnlen (host, hostlen);
-                       size_t scopelen = 0;
-
-                       scopebuf[0] = SCOPE_DELIMITER;
-                       scopebuf[1] = '\0';
-                       scopeptr = &scopebuf[1];
-
-                       if (IN6_IS_ADDR_LINKLOCAL (&sin6p->sin6_addr)
-                           || IN6_IS_ADDR_MC_LINKLOCAL (&sin6p->sin6_addr))
-                         {
-                           if (if_indextoname (scopeid, scopeptr) == NULL)
-                             ++ni_numericscope;
-                           else
-                             scopelen = strlen (scopebuf);
-                         }
-                       else
-                         ++ni_numericscope;
-
-                       if (ni_numericscope)
-                         scopelen = 1 + __snprintf (scopeptr,
-                                                    (scopebuf
-                                                     + sizeof scopebuf
-                                                     - scopeptr),
-                                                    "%u", scopeid);
-
-                       if (real_hostlen + scopelen + 1 > hostlen)
-                         /* Signal the buffer is too small.  This is
-                            what inet_ntop does.  */
-                         c = NULL;
-                       else
-                         memcpy (host + real_hostlen, scopebuf, scopelen + 1);
-                     }
-                 }
-               else
-                 c = inet_ntop (AF_INET,
-                                (const void *) &(((const struct sockaddr_in *) sa)->sin_addr),
-                                host, hostlen);
-               if (c == NULL)
-                 return EAI_OVERFLOW;
-             }
-           ok = 1;
-         }
-       break;
-
-      case AF_LOCAL:
-       if (!(flags & NI_NUMERICHOST))
-         {
-           struct utsname utsname;
-
-           if (!uname (&utsname))
-             {
-               strncpy (host, utsname.nodename, hostlen);
-               break;
-             };
-         };
-
-       if (flags & NI_NAMEREQD)
-         return EAI_NONAME;
-
-       strncpy (host, "localhost", hostlen);
-       break;
+  struct scratch_buffer tmpbuf;
+  scratch_buffer_init (&tmpbuf);
 
-      default:
-       return EAI_FAMILY;
+  if (host != NULL && hostlen > 0)
+    {
+      int result = gni_host (&tmpbuf, sa, addrlen, host, hostlen, flags);
+      if (result != 0)
+       {
+         scratch_buffer_free (&tmpbuf);
+         return result;
+       }
     }
 
   if (serv && (servlen > 0))
-    switch (sa->sa_family)
-      {
-      case AF_INET:
-      case AF_INET6:
-       if (!(flags & NI_NUMERICSERV))
-         {
-           struct servent *s, ts;
-           int e;
-           while ((e = __getservbyport_r (((const struct sockaddr_in *) sa)->sin_port,
-                                          ((flags & NI_DGRAM)
-                                           ? "udp" : "tcp"), &ts,
-                                          tmpbuf.data, tmpbuf.length, &s)))
-             {
-               if (e == ERANGE)
-                 {
-                   if (!scratch_buffer_grow (&tmpbuf))
-                     return EAI_MEMORY;
-                 }
-               else
-                 break;
-             }
-           if (s)
-             {
-               strncpy (serv, s->s_name, servlen);
-               break;
-             }
-         }
-
-       if (__snprintf (serv, servlen, "%d",
-                       ntohs (((const struct sockaddr_in *) sa)->sin_port))
-           + 1 > servlen)
-         return EAI_OVERFLOW;
-
-       break;
-
-      case AF_LOCAL:
-       strncpy (serv, ((const struct sockaddr_un *) sa)->sun_path, servlen);
-       break;
+    {
+      int result = gni_serv (&tmpbuf, sa, addrlen, serv, servlen, flags);
+      if (result != 0)
+       {
+         scratch_buffer_free (&tmpbuf);
+         return result;
+       }
     }
 
   if (host && (hostlen > 0))
     host[hostlen-1] = 0;
   if (serv && (servlen > 0))
     serv[servlen-1] = 0;
+  scratch_buffer_free (&tmpbuf);
   return 0;
 }
 libc_hidden_def (getnameinfo)