/*
- *
- * 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("$Id$");
+RCSID("$OpenBSD: auth-rhosts.c,v 1.19 2001/01/21 19:05:42 markus Exp $");
#include "packet.h"
-#include "ssh.h"
#include "xmalloc.h"
#include "uidswap.h"
+#include "pathnames.h"
+#include "log.h"
#include "servconf.h"
+#include "canohost.h"
-/* This function processes an rhosts-style file (.rhosts, .shosts, or
- /etc/hosts.equiv). This returns true if authentication can be granted
- based on the file, and returns zero otherwise. */
+/*
+ * This function processes an rhosts-style file (.rhosts, .shosts, or
+ * /etc/hosts.equiv). This returns true if authentication can be granted
+ * based on the file, and returns zero otherwise.
+ */
-int
+int
check_rhosts_file(const char *filename, const char *hostname,
const char *ipaddr, const char *client_user,
const char *server_user)
if (!f)
return 0;
- /* Go through the file, checking every entry. */
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;
if (*cp == '#' || *cp == '\n' || !*cp)
continue;
- /* NO_PLUS is supported at least on OSF/1. We skip it (we
- don't ever support the plus syntax). */
+ /*
+ * NO_PLUS is supported at least on OSF/1. We skip it (we
+ * don't ever support the plus syntax).
+ */
if (strncmp(cp, "NO_PLUS", 7) == 0)
continue;
- /* This should be safe because each buffer is as big as
- the whole string, and thus cannot be overwritten. */
+ /*
+ * 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)) {
case 0:
packet_send_debug("Found empty line in %.100s.", filename);
return 0;
}
-/* Tries to authenticate the user using the .shosts or .rhosts file.
- Returns true if authentication succeeds. If ignore_rhosts is
- true, only /etc/hosts.equiv will be considered (.rhosts and .shosts
- are ignored). */
+/*
+ * Tries to authenticate the user using the .shosts or .rhosts file. Returns
+ * true if authentication succeeds. If ignore_rhosts is true, only
+ * /etc/hosts.equiv will be considered (.rhosts and .shosts are ignored).
+ */
-int
+int
auth_rhosts(struct passwd *pw, const char *client_user)
{
extern ServerOptions options;
const char *hostname, *ipaddr;
struct stat st;
static const char *rhosts_files[] = {".shosts", ".rhosts", NULL};
- unsigned int rhosts_file_index;
+ u_int rhosts_file_index;
- /* Quick check: if the user has no .shosts or .rhosts files,
- return failure immediately without doing costly lookups from
- name servers. */
+ /* no user given */
+ if (pw == NULL)
+ return 0;
/* Switch to the user's uid. */
temporarily_use_uid(pw->pw_uid);
+ /*
+ * 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++) {
/* Check users .rhosts or .shosts. */
/* 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;
- /* Get the name, address, and port of the remote host. */
hostname = get_canonical_hostname();
ipaddr = get_remote_ipaddr();
hostname, ipaddr);
return 1;
}
- if (check_rhosts_file(SSH_HOSTS_EQUIV, hostname, ipaddr, client_user,
+ if (check_rhosts_file(_PATH_SSH_HOSTS_EQUIV, hostname, ipaddr, client_user,
pw->pw_name)) {
packet_send_debug("Accepted for %.100s [%.100s] by %.100s.",
- hostname, ipaddr, SSH_HOSTS_EQUIV);
+ hostname, ipaddr, _PATH_SSH_HOSTS_EQUIV);
return 1;
}
}
- /* Check that the home directory is owned by root or the user, and
- is not group or world writable. */
+ /*
+ * Check that the home directory is owned by root or the user, and is
+ * 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 %.100: no home directory %.200s",
+ packet_send_debug("Rhosts authentication refused for %.100s: no home directory %.200s",
pw->pw_name, pw->pw_dir);
return 0;
}
if (stat(buf, &st) < 0)
continue;
- /* Make sure that the file is either owned by the user or
- by root, and make sure it is not writable by anyone but
- the owner. This is to help avoid novices accidentally
- allowing access to their account by anyone. */
+ /*
+ * Make sure that the file is either owned by the user or by
+ * root, and make sure it is not writable by anyone but the
+ * owner. This is to help avoid novices accidentally
+ * allowing access to their account by anyone.
+ */
if (options.strict_modes &&
((st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
(st.st_mode & 022) != 0)) {