+/* $OpenBSD: auth-rhosts.c,v 1.43 2008/06/13 14:18:51 dtucker Exp $ */
/*
- *
- * auth-rhosts.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Fri Mar 17 05:12:18 1995 ylo
- *
* Rhosts authentication. This file contains code to check whether to admit
* the login based on rhosts authentication. This file also processes
* /etc/hosts.equiv.
*
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
*/
#include "includes.h"
-RCSID("$OpenBSD: auth-rhosts.c,v 1.14 2000/06/20 01:39:38 markus Exp $");
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_NETGROUP_H
+# include <netgroup.h>
+#endif
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+#include <fcntl.h>
+#include <unistd.h>
#include "packet.h"
-#include "ssh.h"
-#include "xmalloc.h"
+#include "buffer.h"
#include "uidswap.h"
+#include "pathnames.h"
+#include "log.h"
#include "servconf.h"
+#include "canohost.h"
+#include "key.h"
+#include "hostfile.h"
+#include "auth.h"
+#include "misc.h"
+
+/* import */
+extern ServerOptions options;
+extern int use_privsep;
/*
* This function processes an rhosts-style file (.rhosts, .shosts, or
* based on the file, and returns zero otherwise.
*/
-int
+static int
check_rhosts_file(const char *filename, const char *hostname,
const char *ipaddr, const char *client_user,
const char *server_user)
{
FILE *f;
char buf[1024]; /* Must not be larger than host, user, dummy below. */
+ int fd;
+ struct stat st;
/* Open the .rhosts file, deny if unreadable */
- f = fopen(filename, "r");
- if (!f)
+ if ((fd = open(filename, O_RDONLY|O_NONBLOCK)) == -1)
return 0;
-
+ if (fstat(fd, &st) == -1) {
+ close(fd);
+ return 0;
+ }
+ if (!S_ISREG(st.st_mode)) {
+ logit("User %s hosts file %s is not a regular file",
+ server_user, filename);
+ close(fd);
+ return 0;
+ }
+ unset_nonblock(fd);
+ if ((f = fdopen(fd, "r")) == NULL) {
+ close(fd);
+ return 0;
+ }
while (fgets(buf, sizeof(buf), f)) {
/* All three must be at least as big as buf to avoid overflows. */
char hostbuf[1024], userbuf[1024], dummy[1024], *host, *user, *cp;
* This should be safe because each buffer is as big as the
* whole string, and thus cannot be overwritten.
*/
- switch (sscanf(buf, "%s %s %s", hostbuf, userbuf, dummy)) {
+ switch (sscanf(buf, "%1023s %1023s %1023s", hostbuf, userbuf,
+ dummy)) {
case 0:
- packet_send_debug("Found empty line in %.100s.", filename);
+ auth_debug_add("Found empty line in %.100s.", filename);
continue;
case 1:
/* Host name only. */
/* Got both host and user name. */
break;
case 3:
- packet_send_debug("Found garbage in %.100s.", filename);
+ auth_debug_add("Found garbage in %.100s.", filename);
continue;
default:
/* Weird... */
/* Check for empty host/user names (particularly '+'). */
if (!host[0] || !user[0]) {
/* We come here if either was '+' or '-'. */
- packet_send_debug("Ignoring wild host/user names in %.100s.",
- filename);
+ auth_debug_add("Ignoring wild host/user names in %.100s.",
+ filename);
continue;
}
/* Verify that host name matches. */
/* If the entry was negated, deny access. */
if (negated) {
- packet_send_debug("Matched negative entry in %.100s.",
- filename);
+ auth_debug_add("Matched negative entry in %.100s.",
+ filename);
return 0;
}
/* Accept authentication. */
int
auth_rhosts(struct passwd *pw, const char *client_user)
{
- extern ServerOptions options;
- char buf[1024];
const char *hostname, *ipaddr;
+
+ hostname = get_canonical_hostname(options.use_dns);
+ ipaddr = get_remote_ipaddr();
+ return auth_rhosts2(pw, client_user, hostname, ipaddr);
+}
+
+static int
+auth_rhosts2_raw(struct passwd *pw, const char *client_user, const char *hostname,
+ const char *ipaddr)
+{
+ char buf[1024];
struct stat st;
static const char *rhosts_files[] = {".shosts", ".rhosts", NULL};
- unsigned int rhosts_file_index;
+ u_int rhosts_file_index;
+
+ debug2("auth_rhosts2: clientuser %s hostname %s ipaddr %s",
+ client_user, hostname, ipaddr);
/* Switch to the user's uid. */
- temporarily_use_uid(pw->pw_uid);
+ temporarily_use_uid(pw);
/*
* Quick check: if the user has no .shosts or .rhosts files, return
* failure immediately without doing costly lookups from name
* servers.
*/
for (rhosts_file_index = 0; rhosts_files[rhosts_file_index];
- rhosts_file_index++) {
+ rhosts_file_index++) {
/* Check users .rhosts or .shosts. */
snprintf(buf, sizeof buf, "%.500s/%.100s",
pw->pw_dir, rhosts_files[rhosts_file_index]);
/* Deny if The user has no .shosts or .rhosts file and there are no system-wide files. */
if (!rhosts_files[rhosts_file_index] &&
- stat("/etc/hosts.equiv", &st) < 0 &&
- stat(SSH_HOSTS_EQUIV, &st) < 0)
+ stat(_PATH_RHOSTS_EQUIV, &st) < 0 &&
+ stat(_PATH_SSH_HOSTS_EQUIV, &st) < 0)
return 0;
- hostname = get_canonical_hostname();
- ipaddr = get_remote_ipaddr();
-
/* If not logging in as superuser, try /etc/hosts.equiv and shosts.equiv. */
if (pw->pw_uid != 0) {
- if (check_rhosts_file("/etc/hosts.equiv", hostname, ipaddr, client_user,
- pw->pw_name)) {
- packet_send_debug("Accepted for %.100s [%.100s] by /etc/hosts.equiv.",
- hostname, ipaddr);
+ if (check_rhosts_file(_PATH_RHOSTS_EQUIV, hostname, ipaddr,
+ client_user, pw->pw_name)) {
+ auth_debug_add("Accepted for %.100s [%.100s] by /etc/hosts.equiv.",
+ hostname, ipaddr);
return 1;
}
- if (check_rhosts_file(SSH_HOSTS_EQUIV, hostname, ipaddr, client_user,
- pw->pw_name)) {
- packet_send_debug("Accepted for %.100s [%.100s] by %.100s.",
- hostname, ipaddr, SSH_HOSTS_EQUIV);
+ if (check_rhosts_file(_PATH_SSH_HOSTS_EQUIV, hostname, ipaddr,
+ client_user, pw->pw_name)) {
+ auth_debug_add("Accepted for %.100s [%.100s] by %.100s.",
+ hostname, ipaddr, _PATH_SSH_HOSTS_EQUIV);
return 1;
}
}
* not group or world writable.
*/
if (stat(pw->pw_dir, &st) < 0) {
- log("Rhosts authentication refused for %.100s: no home directory %.200s",
- pw->pw_name, pw->pw_dir);
- packet_send_debug("Rhosts authentication refused for %.100s: no home directory %.200s",
- pw->pw_name, pw->pw_dir);
+ logit("Rhosts authentication refused for %.100s: "
+ "no home directory %.200s", pw->pw_name, pw->pw_dir);
+ auth_debug_add("Rhosts authentication refused for %.100s: "
+ "no home directory %.200s", pw->pw_name, pw->pw_dir);
return 0;
}
if (options.strict_modes &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
- (st.st_mode & 022) != 0)) {
- log("Rhosts authentication refused for %.100s: bad ownership or modes for home directory.",
- pw->pw_name);
- packet_send_debug("Rhosts authentication refused for %.100s: bad ownership or modes for home directory.",
- pw->pw_name);
+ (st.st_mode & 022) != 0)) {
+ logit("Rhosts authentication refused for %.100s: "
+ "bad ownership or modes for home directory.", pw->pw_name);
+ auth_debug_add("Rhosts authentication refused for %.100s: "
+ "bad ownership or modes for home directory.", pw->pw_name);
return 0;
}
/* Temporarily use the user's uid. */
- temporarily_use_uid(pw->pw_uid);
+ temporarily_use_uid(pw);
/* Check all .rhosts files (currently .shosts and .rhosts). */
for (rhosts_file_index = 0; rhosts_files[rhosts_file_index];
- rhosts_file_index++) {
+ rhosts_file_index++) {
/* Check users .rhosts or .shosts. */
snprintf(buf, sizeof buf, "%.500s/%.100s",
pw->pw_dir, rhosts_files[rhosts_file_index]);
*/
if (options.strict_modes &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
- (st.st_mode & 022) != 0)) {
- log("Rhosts authentication refused for %.100s: bad modes for %.200s",
+ (st.st_mode & 022) != 0)) {
+ logit("Rhosts authentication refused for %.100s: bad modes for %.200s",
pw->pw_name, buf);
- packet_send_debug("Bad file modes for %.200s", buf);
+ auth_debug_add("Bad file modes for %.200s", buf);
continue;
}
/* Check if we have been configured to ignore .rhosts and .shosts files. */
if (options.ignore_rhosts) {
- packet_send_debug("Server has been configured to ignore %.100s.",
- rhosts_files[rhosts_file_index]);
+ auth_debug_add("Server has been configured to ignore %.100s.",
+ rhosts_files[rhosts_file_index]);
continue;
}
/* Check if authentication is permitted by the file. */
if (check_rhosts_file(buf, hostname, ipaddr, client_user, pw->pw_name)) {
- packet_send_debug("Accepted by %.100s.",
- rhosts_files[rhosts_file_index]);
+ auth_debug_add("Accepted by %.100s.",
+ rhosts_files[rhosts_file_index]);
/* Restore the privileged uid. */
restore_uid();
+ auth_debug_add("Accepted host %s ip %s client_user %s server_user %s",
+ hostname, ipaddr, client_user, pw->pw_name);
return 1;
}
}
restore_uid();
return 0;
}
+
+int
+auth_rhosts2(struct passwd *pw, const char *client_user, const char *hostname,
+ const char *ipaddr)
+{
+ int ret;
+
+ auth_debug_reset();
+ ret = auth_rhosts2_raw(pw, client_user, hostname, ipaddr);
+ if (!use_privsep)
+ auth_debug_send();
+ return ret;
+}
andersk / openssh.git / blobdiff