Implement new mode for NIS passwd.adjunct.byname table.

The passwd.adjunct.byname table will not be used to fill in password fields
in the passwd.byname replies.  Instead it is used to synthesize the
shadow.byname table, should it be missing.  This is a useful mode in some
installations involving Solaris.

1 files changed, 58 insertions, 21 deletions

diff --git a/nis/nss_nis/nis-spwd.c b/nis/nss_nis/nis-spwd.c
index 0fc4e17..3cf913b 100644
--- a/nis/nss_nis/nis-spwd.c
+++ b/nis/nss_nis/nis-spwd.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996-1998,2001,2002,2003,2006 Free Software Foundation, Inc.
+/* Copyright (C) 1996-1998,2001-2003,2006,2010 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.
 
@@ -31,6 +31,7 @@
 #include <rpcsvc/ypclnt.h>
 
 #include "nss-nis.h"
+#include <libnsl.h>
 
 /* Get the declaration of the parser function.  */
 #define ENTNAME spent
@@ -41,7 +42,8 @@
 /* Protect global state against multiple changers */
 __libc_lock_define_initialized (static, lock)
 
-static bool_t new_start = 1;
+static bool new_start = true;
+static bool ent_adjunct_used;
 static char *oldkey;
 static int oldkeylen;
 
@@ -50,7 +52,8 @@ _nss_nis_setspent (int stayopen)
 {
   __libc_lock_lock (lock);
 
-  new_start = 1;
+  new_start = true;
+  ent_adjunct_used = false;
   free (oldkey);
   oldkey = NULL;
   oldkeylen = 0;
@@ -83,32 +86,50 @@ internal_nis_getspent_r (struct spwd *sp, char *buffer, size_t buflen,
       int yperr;
 
       if (new_start)
-        yperr = yp_first (domain, "shadow.byname", &outkey, &keylen, &result,
-			  &len);
+	{
+	  yperr = yp_first (domain, "shadow.byname", &outkey, &keylen, &result,
+			    &len);
+	  if (__builtin_expect (yperr == YPERR_MAP, 0)
+	      && (_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW))
+	    {
+	      free (result);
+	      yperr = yp_first (domain, "passwd.adjunct.byname", &outkey,
+				&keylen, &result, &len);
+	      ent_adjunct_used = true;
+	    }
+	}
       else
-        yperr = yp_next (domain, "shadow.byname", oldkey, oldkeylen, &outkey,
-			 &keylen, &result, &len);
+	yperr = yp_next (domain, (ent_adjunct_used
+				  ? "passwd.adjunct.byname" : "shadow.byname"),
+			 oldkey, oldkeylen, &outkey, &keylen, &result, &len);
 
       if (__builtin_expect (yperr != YPERR_SUCCESS, 0))
-        {
+	{
 	  enum nss_status retval = yperr2nss (yperr);
 
 	  if (retval == NSS_STATUS_TRYAGAIN)
 	    *errnop = errno;
-          return retval;
-        }
+	  return retval;
+	}
 
-      if (__builtin_expect ((size_t) (len + 1) > buflen, 0))
-        {
-          free (result);
+      if (__builtin_expect ((size_t) (len + (ent_adjunct_used ? 3 : 1))
+			    > buflen, 0))
+	{
+	  free (result);
 	  *errnop = ERANGE;
-          return NSS_STATUS_TRYAGAIN;
-        }
+	  return NSS_STATUS_TRYAGAIN;
+	}
 
       char *p = strncpy (buffer, result, len);
-      buffer[len] = '\0';
+      if (ent_adjunct_used)
+	/* This is an ugly trick.  The format of passwd.adjunct.byname almost
+	   matches the shadow.byname format except that the last two fields
+	   are missing.  Synthesize them by marking them empty.  */
+	strcpy (&buffer[len], "::");
+      else
+	buffer[len] = '\0';
       while (isspace (*p))
-        ++p;
+	++p;
       free (result);
 
       parse_res = _nss_files_parse_spent (p, sp, (void *) buffer, buflen,
@@ -123,7 +144,7 @@ internal_nis_getspent_r (struct spwd *sp, char *buffer, size_t buflen,
       free (oldkey);
       oldkey = outkey;
       oldkeylen = keylen;
-      new_start = 0;
+      new_start = false;
     }
   while (!parse_res);
 
@@ -154,15 +175,25 @@ _nss_nis_getspnam_r (const char *name, struct spwd *sp,
       *errnop = EINVAL;
       return NSS_STATUS_UNAVAIL;
     }
+  const size_t name_len = strlen (name);
 
   char *domain;
   if (__builtin_expect (yp_get_default_domain (&domain), 0))
     return NSS_STATUS_UNAVAIL;
 
+  bool adjunct_used = false;
   char *result;
   int len;
-  int yperr = yp_match (domain, "shadow.byname", name, strlen (name), &result,
+  int yperr = yp_match (domain, "shadow.byname", name, name_len, &result,
 			&len);
+  if (__builtin_expect (yperr == YPERR_MAP, 0)
+      && (_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW))
+    {
+      free (result);
+      yperr = yp_match (domain, "passwd.adjunct.byname", name, name_len,
+			&result, &len);
+      adjunct_used = true;
+    }
 
   if (__builtin_expect (yperr != YPERR_SUCCESS, 0))
     {
@@ -173,7 +204,7 @@ _nss_nis_getspnam_r (const char *name, struct spwd *sp,
       return retval;
     }
 
-  if (__builtin_expect ((size_t) (len + 1) > buflen, 0))
+  if (__builtin_expect ((size_t) (len + (adjunct_used ? 3 : 1)) > buflen, 0))
     {
       free (result);
       *errnop = ERANGE;
@@ -181,7 +212,13 @@ _nss_nis_getspnam_r (const char *name, struct spwd *sp,
     }
 
   char *p = strncpy (buffer, result, len);
-  buffer[len] = '\0';
+  if (__builtin_expect (adjunct_used, false))
+    /* This is an ugly trick.  The format of passwd.adjunct.byname almost
+       matches the shadow.byname format except that the last two fields
+       are missing.  Synthesize them by marking them empty.  */
+    strcpy (&buffer[len], "::");
+  else
+    buffer[len] = '\0';
   while (isspace (*p))
     ++p;
   free (result);