A nice *big* change to the fundemental way we do things.

Samba (ab)uses the returns from getpwnam() a lot - in particular it keeps
them around for a long time - often past the next call...

This adds a getpwnam_alloc and a getpwuid_alloc to the collection.

These function as expected, returning a malloced structure that can be
free()ed with passwd_free(&passwd).

This patch also cuts down on the number of calls to getpwnam - mostly by
taking advantage of the fact that the passdb interface is already
case-insensiteve.

With this patch most of the recursive cases have been removed (that I know
of) and the problems are reduced further by not using the sys_ interface
in the new code.  This means that pointers to the cache won't be affected.
(This is a tempoary HACK, I intend to kill the password cache entirly).

The only change I'm a little worried about is the change to
rpc_server/srv_samr_nt.c for private groups.  In this case we are getting
groups from the new group mapping DB.  Do we still need to check for private
groups?  I've toned down the check to a case sensitve match with the new code,
but we might be able to kill it entirly.

I've also added a make_modifyable_passwd() function, that copies a passwd
struct into the form that the old sys_getpw* code provided.  As far as I can
tell this is only actually used in the pass_check.c crazies, where I moved
the final 'special case' for shadow passwords (out of _Get_Pwnam()).

The matching case for getpwent() is dealt with already, in lib/util_getent.c

Also included in here is a small change to register the [homes] share at vuid
creation rather than just in one varient of the session setup.  (This picks
up the SPNEGO cases).  The home directory is now stored on the vuid, and I
am hoping this might provide a saner way to do %H substitions.

TODO:  Kill off remaining Get_Pwnam_Modify calls (they are not needed), change
the remaining sys_getpwnam() callers to use getpwnam_alloc() and move
Get_Pwnam to return an allocated struct.

Andrew Bartlett
(This used to be commit 1d86c7f94230bc53daebd4d2cd829da6292e05da)

3 files changed, 140 insertions, 29 deletions

diff --git a/source3/lib/substitute.c b/source3/lib/substitute.c
index 5a2bc1d890..c02ec9556a 100644
--- a/source3/lib/substitute.c
+++ b/source3/lib/substitute.c
@@ -92,7 +92,6 @@ static size_t expand_env_var(char *p, int len)
 static char *automount_path(const char *user_name)
 {
 	static pstring server_path;
-	struct passwd *pass;
 
 	/* use the passwd entry as the default */
 	/* this will be the default if WITH_AUTOMOUNT is not used or fails */
diff --git a/source3/lib/username.c b/source3/lib/username.c
index 81408f4569..9541ebeb08 100644
--- a/source3/lib/username.c
+++ b/source3/lib/username.c
@@ -205,29 +205,7 @@ BOOL map_username(char *user)
 }
 
 /****************************************************************************
- Get_Pwnam wrapper
-****************************************************************************/
-
-static struct passwd *_Get_Pwnam(const char *s)
-{
-	struct passwd *ret;
-
-	ret = sys_getpwnam(s);
-	if (ret) {
-#ifdef HAVE_GETPWANAM
-		struct passwd_adjunct *pwret;
-		pwret = getpwanam(s);
-		if (pwret && pwret->pwa_passwd)
-			pstrcpy(ret->pw_passwd,pwret->pwa_passwd);
-#endif
-	}
-
-	return(ret);
-}
-
-
-/****************************************************************************
- * A wrapper for getpwnam().  The following variations are tried:
+ * A wrapper for sys_getpwnam().  The following variations are tried:
  *   - as transmitted
  *   - in all lower case if this differs from transmitted
  *   - in all upper case if this differs from transmitted
@@ -248,23 +226,23 @@ struct passwd *Get_Pwnam_internals(const char *user, char *user2)
 	   common case on UNIX systems */
 	strlower(user2);
 	DEBUG(5,("Trying _Get_Pwnam(), username as lowercase is %s\n",user2));
-	ret = _Get_Pwnam(user2);
+	ret = sys_getpwnam(user2);
 	if(ret)
 		goto done;
 
 	/* Try as given, if username wasn't originally lowercase */
 	if(strcmp(user,user2) != 0) {
 		DEBUG(5,("Trying _Get_Pwnam(), username as given is %s\n",user));
-		ret = _Get_Pwnam(user);
+		ret = sys_getpwnam(user);
 		if(ret)
 			goto done;
-	}	
+	}
 
 	/* Try as uppercase, if username wasn't originally uppercase */
 	strupper(user2);
 	if(strcmp(user,user2) != 0) {
 		DEBUG(5,("Trying _Get_Pwnam(), username as uppercase is %s\n",user2));
-		ret = _Get_Pwnam(user2);
+		ret = sys_getpwnam(user2);
 		if(ret)
 			goto done;
 	}
@@ -272,7 +250,7 @@ struct passwd *Get_Pwnam_internals(const char *user, char *user2)
 	/* Try all combinations up to usernamelevel */
 	strlower(user2);
 	DEBUG(5,("Checking combinations of %d uppercase letters in %s\n",lp_usernamelevel(),user2));
-	ret = uname_string_combinations(user2, _Get_Pwnam, lp_usernamelevel());
+	ret = uname_string_combinations(user2, sys_getpwnam, lp_usernamelevel());
 
 done:
 	DEBUG(5,("Get_Pwnam %s find a valid username!\n",ret ? "did":"didn't"));
diff --git a/source3/lib/util_pw.c b/source3/lib/util_pw.c
new file mode 100644
index 0000000000..3367a6cdc0
--- /dev/null
+++ b/source3/lib/util_pw.c
@@ -0,0 +1,134 @@
+/* 
+   Unix SMB/Netbios implementation.
+   Version 3.0.
+
+   Safe versions of getpw* calls
+
+   Copyright (C) Andrew Bartlett 2002
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program 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 General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+struct passwd *make_modifyable_passwd(const struct passwd *from)
+{
+	struct passwd *ret = smb_xmalloc(sizeof(*ret));
+/*  This is the assumed shape of the members by certain parts of the code...
+	fstring 	pw_name;
+	fstring 	pw_passwd;
+	fstring		pw_gecos;
+	pstring		pw_dir;
+	pstring		pw_shell;
+*/
+	char *pw_name = smb_xmalloc(sizeof(fstring));
+	char *pw_passwd = smb_xmalloc(sizeof(fstring));
+	char *pw_gecos = smb_xmalloc(sizeof(fstring));
+	char *pw_dir = smb_xmalloc(sizeof(pstring));
+	char *pw_shell = smb_xmalloc(sizeof(pstring));
+
+	ZERO_STRUCTP(ret);
+
+	/* 
+	 * Now point the struct's members as the 
+	 * newly allocated buffers:
+	 */
+
+	ret->pw_name = pw_name;
+	fstrcpy(ret->pw_name, from->pw_name);
+
+	ret->pw_passwd = pw_passwd;
+	fstrcpy(ret->pw_passwd, from->pw_passwd);
+
+	ret->pw_uid = from->pw_uid;
+	ret->pw_gid = from->pw_gid;
+
+	ret->pw_gecos = pw_gecos;
+	fstrcpy(ret->pw_gecos, from->pw_gecos);
+
+	ret->pw_dir = pw_dir;
+	pstrcpy(ret->pw_dir, from->pw_dir);
+
+	ret->pw_shell = pw_shell;
+	pstrcpy(ret->pw_shell, from->pw_shell);
+
+	return ret;
+}
+
+static struct passwd *alloc_copy_passwd(const struct passwd *from) 
+{
+	struct passwd *ret = smb_xmalloc(sizeof(*ret));
+	ZERO_STRUCTP(ret);
+	ret->pw_name = smb_xstrdup(from->pw_name);
+	ret->pw_passwd = smb_xstrdup(from->pw_passwd);
+	ret->pw_uid = from->pw_uid;
+	ret->pw_gid = from->pw_gid;
+	ret->pw_gecos = smb_xstrdup(from->pw_gecos);
+	ret->pw_dir = smb_xstrdup(from->pw_dir);
+	ret->pw_shell = smb_xstrdup(from->pw_shell);
+	return ret;
+}
+
+void passwd_free (struct passwd **buf)
+{
+	if (!*buf) {
+		DEBUG(0, ("attempted double-free of allocated passwd\n"));
+		return;
+	}
+
+	SAFE_FREE((*buf)->pw_name);
+	SAFE_FREE((*buf)->pw_passwd);
+	SAFE_FREE((*buf)->pw_gecos);
+	SAFE_FREE((*buf)->pw_dir);
+	SAFE_FREE((*buf)->pw_shell);
+
+	SAFE_FREE(*buf);
+}
+
+struct passwd *getpwnam_alloc(const char *name) 
+{
+	struct passwd *temp;
+
+	temp = getpwnam(name);
+	
+	if (!temp) {
+#if 0
+		if (errno == ENOMEM) {
+			/* what now? */
+		}
+#endif
+		return NULL;
+	}
+
+	return alloc_copy_passwd(temp);
+}
+
+struct passwd *getpwuid_alloc(uid_t uid) 
+{
+	struct passwd *temp;
+
+	temp = getpwuid(uid);
+	
+	if (!temp) {
+#if 0
+		if (errno == ENOMEM) {
+			/* what now? */
+		}
+#endif
+		return NULL;
+	}
+
+	return alloc_copy_passwd(temp);
+}