s3-auth: Moved smbd user functions to a generic place.

Reviewed-by: Simo Sorce <idra@samba.org>

1 files changed, 406 insertions, 0 deletions

diff --git a/source3/auth/user_util.c b/source3/auth/user_util.c
new file mode 100644
index 0000000000..3d7123c18e
--- /dev/null
+++ b/source3/auth/user_util.c
@@ -0,0 +1,406 @@
+/*
+   Unix SMB/CIFS implementation.
+   Username handling
+   Copyright (C) Andrew Tridgell 1992-1998
+   Copyright (C) Jeremy Allison 1997-2001.
+   Copyright (C) Volker Lendecke 2006
+
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+/*******************************************************************
+ Map a username from a dos name to a unix name by looking in the username
+ map. Note that this modifies the name in place.
+ This is the main function that should be called *once* on
+ any incoming or new username - in order to canonicalize the name.
+ This is being done to de-couple the case conversions from the user mapping
+ function. Previously, the map_username was being called
+ every time Get_Pwnam_alloc was called.
+ Returns True if username was changed, false otherwise.
+********************************************************************/
+
+static char *last_from = NULL;
+static char *last_to = NULL;
+
+static const char *get_last_from(void)
+{
+	if (!last_from) {
+		return "";
+	}
+	return last_from;
+}
+
+static const char *get_last_to(void)
+{
+	if (!last_to) {
+		return "";
+	}
+	return last_to;
+}
+
+static bool set_last_from_to(const char *from, const char *to)
+{
+	char *orig_from = last_from;
+	char *orig_to = last_to;
+
+	last_from = SMB_STRDUP(from);
+	last_to = SMB_STRDUP(to);
+
+	SAFE_FREE(orig_from);
+	SAFE_FREE(orig_to);
+
+	if (!last_from || !last_to) {
+		SAFE_FREE(last_from);
+		SAFE_FREE(last_to);
+		return false;
+	}
+	return true;
+}
+
+static char *skip_space(char *s)
+{
+	while (isspace((int)(*s))) {
+		s += 1;
+	}
+	return s;
+}
+
+static bool fetch_map_from_gencache(fstring user)
+{
+	char *key, *value;
+	bool found;
+
+	if (lp_username_map_cache_time() == 0) {
+		return false;
+	}
+
+	key = talloc_asprintf_strupper_m(talloc_tos(), "USERNAME_MAP/%s",
+					 user);
+	if (key == NULL) {
+		return false;
+	}
+	found = gencache_get(key, &value, NULL);
+	TALLOC_FREE(key);
+	if (!found) {
+		return false;
+	}
+	fstrcpy(user, value);
+	SAFE_FREE(value);
+	return true;
+}
+
+static void store_map_in_gencache(const char *from, const char *to)
+{
+	char *key;
+	int cache_time = lp_username_map_cache_time();
+
+	if (cache_time == 0) {
+		return;
+	}
+
+	key = talloc_asprintf_strupper_m(talloc_tos(), "USERNAME_MAP/%s",
+					 from);
+        if (key == NULL) {
+                return;
+        }
+	gencache_set(key, to, cache_time + time(NULL));
+	TALLOC_FREE(key);
+}
+
+/****************************************************************************
+ Check if a user is in a netgroup user list. If at first we don't succeed,
+ try lower case.
+****************************************************************************/
+
+bool user_in_netgroup(const char *user, const char *ngname)
+{
+#ifdef HAVE_NETGROUP
+	static char *my_yp_domain = NULL;
+	fstring lowercase_user;
+
+	if (my_yp_domain == NULL) {
+		yp_get_default_domain(&my_yp_domain);
+	}
+
+	if (my_yp_domain == NULL) {
+		DEBUG(5,("Unable to get default yp domain, "
+			"let's try without specifying it\n"));
+	}
+
+	DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
+		user, my_yp_domain?my_yp_domain:"(ANY)", ngname));
+
+	if (innetgr(ngname, NULL, user, my_yp_domain)) {
+		DEBUG(5,("user_in_netgroup: Found\n"));
+		return true;
+	}
+
+	/*
+	 * Ok, innetgr is case sensitive. Try once more with lowercase
+	 * just in case. Attempt to fix #703. JRA.
+	 */
+	fstrcpy(lowercase_user, user);
+	strlower_m(lowercase_user);
+
+	if (strcmp(user,lowercase_user) == 0) {
+		/* user name was already lower case! */
+		return false;
+	}
+
+	DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
+		lowercase_user, my_yp_domain?my_yp_domain:"(ANY)", ngname));
+
+	if (innetgr(ngname, NULL, lowercase_user, my_yp_domain)) {
+		DEBUG(5,("user_in_netgroup: Found\n"));
+		return true;
+	}
+#endif /* HAVE_NETGROUP */
+	return false;
+}
+
+/****************************************************************************
+ Check if a user is in a user list - can check combinations of UNIX
+ and netgroup lists.
+****************************************************************************/
+
+bool user_in_list(const char *user,const char **list)
+{
+	if (!list || !*list)
+		return False;
+
+	DEBUG(10,("user_in_list: checking user %s in list\n", user));
+
+	while (*list) {
+
+		DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
+			  user, *list));
+
+		/*
+		 * Check raw username.
+		 */
+		if (strequal(user, *list))
+			return(True);
+
+		/*
+		 * Now check to see if any combination
+		 * of UNIX and netgroups has been specified.
+		 */
+
+		if(**list == '@') {
+			/*
+			 * Old behaviour. Check netgroup list
+			 * followed by UNIX list.
+			 */
+			if(user_in_netgroup(user, *list +1))
+				return True;
+			if(user_in_group(user, *list +1))
+				return True;
+		} else if (**list == '+') {
+
+			if((*(*list +1)) == '&') {
+				/*
+				 * Search UNIX list followed by netgroup.
+				 */
+				if(user_in_group(user, *list +2))
+					return True;
+				if(user_in_netgroup(user, *list +2))
+					return True;
+
+			} else {
+
+				/*
+				 * Just search UNIX list.
+				 */
+
+				if(user_in_group(user, *list +1))
+					return True;
+			}
+
+		} else if (**list == '&') {
+
+			if(*(*list +1) == '+') {
+				/*
+				 * Search netgroup list followed by UNIX list.
+				 */
+				if(user_in_netgroup(user, *list +2))
+					return True;
+				if(user_in_group(user, *list +2))
+					return True;
+			} else {
+				/*
+				 * Just search netgroup list.
+				 */
+				if(user_in_netgroup(user, *list +1))
+					return True;
+			}
+		}
+
+		list++;
+	}
+	return(False);
+}
+
+bool map_username(fstring user)
+{
+	XFILE *f;
+	char *mapfile = lp_username_map();
+	char *s;
+	char buf[512];
+	bool mapped_user = False;
+	char *cmd = lp_username_map_script();
+
+	if (!*user)
+		return false;
+
+	if (strequal(user,get_last_to()))
+		return false;
+
+	if (strequal(user,get_last_from())) {
+		DEBUG(3,("Mapped user %s to %s\n",user,get_last_to()));
+		fstrcpy(user,get_last_to());
+		return true;
+	}
+
+	if (fetch_map_from_gencache(user)) {
+		return true;
+	}
+
+	/* first try the username map script */
+
+	if ( *cmd ) {
+		char **qlines;
+		char *command = NULL;
+		int numlines, ret, fd;
+
+		command = talloc_asprintf(talloc_tos(),
+					"%s \"%s\"",
+					cmd,
+					user);
+		if (!command) {
+			return false;
+		}
+
+		DEBUG(10,("Running [%s]\n", command));
+		ret = smbrun(command, &fd);
+		DEBUGADD(10,("returned [%d]\n", ret));
+
+		TALLOC_FREE(command);
+
+		if ( ret != 0 ) {
+			if (fd != -1)
+				close(fd);
+			return False;
+		}
+
+		numlines = 0;
+		qlines = fd_lines_load(fd, &numlines, 0, talloc_tos());
+		DEBUGADD(10,("Lines returned = [%d]\n", numlines));
+		close(fd);
+
+		/* should be either no lines or a single line with the mapped username */
+
+		if (numlines && qlines) {
+			DEBUG(3,("Mapped user %s to %s\n", user, qlines[0] ));
+			set_last_from_to(user, qlines[0]);
+			store_map_in_gencache(user, qlines[0]);
+			fstrcpy( user, qlines[0] );
+		}
+
+		TALLOC_FREE(qlines);
+
+		return numlines != 0;
+	}
+
+	/* ok.  let's try the mapfile */
+	if (!*mapfile)
+		return False;
+
+	f = x_fopen(mapfile,O_RDONLY, 0);
+	if (!f) {
+		DEBUG(0,("can't open username map %s. Error %s\n",mapfile, strerror(errno) ));
+		return False;
+	}
+
+	DEBUG(4,("Scanning username map %s\n",mapfile));
+
+	while((s=fgets_slash(buf,sizeof(buf),f))!=NULL) {
+		char *unixname = s;
+		char *dosname = strchr_m(unixname,'=');
+		char **dosuserlist;
+		bool return_if_mapped = False;
+
+		if (!dosname)
+			continue;
+
+		*dosname++ = 0;
+
+		unixname = skip_space(unixname);
+
+		if ('!' == *unixname) {
+			return_if_mapped = True;
+			unixname = skip_space(unixname+1);
+		}
+
+		if (!*unixname || strchr_m("#;",*unixname))
+			continue;
+
+		{
+			int l = strlen(unixname);
+			while (l && isspace((int)unixname[l-1])) {
+				unixname[l-1] = 0;
+				l--;
+			}
+		}
+
+		/* skip lines like 'user = ' */
+
+		dosuserlist = str_list_make_v3(talloc_tos(), dosname, NULL);
+		if (!dosuserlist) {
+			DEBUG(0,("Bad username map entry.  Unable to build user list.  Ignoring.\n"));
+			continue;
+		}
+
+		if (strchr_m(dosname,'*') ||
+		    user_in_list(user, (const char **)dosuserlist)) {
+			DEBUG(3,("Mapped user %s to %s\n",user,unixname));
+			mapped_user = True;
+
+			set_last_from_to(user, unixname);
+			store_map_in_gencache(user, unixname);
+			fstrcpy( user, unixname );
+
+			if ( return_if_mapped ) {
+				TALLOC_FREE(dosuserlist);
+				x_fclose(f);
+				return True;
+			}
+		}
+
+		TALLOC_FREE(dosuserlist);
+	}
+
+	x_fclose(f);
+
+	/*
+	 * Setup the last_from and last_to as an optimization so
+	 * that we don't scan the file again for the same user.
+	 */
+
+	set_last_from_to(user, user);
+	store_map_in_gencache(user, user);
+
+	return mapped_user;
+}