diff options
Diffstat (limited to 'crypto/openssh/auth-rhosts.c')
-rw-r--r-- | crypto/openssh/auth-rhosts.c | 309 |
1 files changed, 0 insertions, 309 deletions
diff --git a/crypto/openssh/auth-rhosts.c b/crypto/openssh/auth-rhosts.c deleted file mode 100644 index cd0a796..0000000 --- a/crypto/openssh/auth-rhosts.c +++ /dev/null @@ -1,309 +0,0 @@ -/* $OpenBSD: auth-rhosts.c,v 1.41 2006/08/03 03:34:41 deraadt Exp $ */ -/* - * Author: Tatu Ylonen <ylo@cs.hut.fi> - * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland - * All rights reserved - * 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" - -#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 "packet.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" - -/* import */ -extern ServerOptions options; -extern int use_privsep; - -/* - * 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. - */ - -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. */ - - /* Open the .rhosts file, deny if unreadable */ - f = fopen(filename, "r"); - if (!f) - 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; - int negated; - - for (cp = buf; *cp == ' ' || *cp == '\t'; 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). - */ - 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. - */ - switch (sscanf(buf, "%1023s %1023s %1023s", hostbuf, userbuf, - dummy)) { - case 0: - auth_debug_add("Found empty line in %.100s.", filename); - continue; - case 1: - /* Host name only. */ - strlcpy(userbuf, server_user, sizeof(userbuf)); - break; - case 2: - /* Got both host and user name. */ - break; - case 3: - auth_debug_add("Found garbage in %.100s.", filename); - continue; - default: - /* Weird... */ - continue; - } - - host = hostbuf; - user = userbuf; - negated = 0; - - /* Process negated host names, or positive netgroups. */ - if (host[0] == '-') { - negated = 1; - host++; - } else if (host[0] == '+') - host++; - - if (user[0] == '-') { - negated = 1; - user++; - } else if (user[0] == '+') - user++; - - /* Check for empty host/user names (particularly '+'). */ - if (!host[0] || !user[0]) { - /* We come here if either was '+' or '-'. */ - auth_debug_add("Ignoring wild host/user names in %.100s.", - filename); - continue; - } - /* Verify that host name matches. */ - if (host[0] == '@') { - if (!innetgr(host + 1, hostname, NULL, NULL) && - !innetgr(host + 1, ipaddr, NULL, NULL)) - continue; - } else if (strcasecmp(host, hostname) && strcmp(host, ipaddr) != 0) - continue; /* Different hostname. */ - - /* Verify that user name matches. */ - if (user[0] == '@') { - if (!innetgr(user + 1, NULL, client_user, NULL)) - continue; - } else if (strcmp(user, client_user) != 0) - continue; /* Different username. */ - - /* Found the user and host. */ - fclose(f); - - /* If the entry was negated, deny access. */ - if (negated) { - auth_debug_add("Matched negative entry in %.100s.", - filename); - return 0; - } - /* Accept authentication. */ - return 1; - } - - /* Authentication using this file denied. */ - fclose(f); - 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). - */ - -int -auth_rhosts(struct passwd *pw, const char *client_user) -{ - 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}; - 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); - /* - * 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. */ - snprintf(buf, sizeof buf, "%.500s/%.100s", - pw->pw_dir, rhosts_files[rhosts_file_index]); - if (stat(buf, &st) >= 0) - break; - } - /* Switch back to privileged uid. */ - restore_uid(); - - /* Deny if The user has no .shosts or .rhosts file and there are no system-wide files. */ - if (!rhosts_files[rhosts_file_index] && - stat(_PATH_RHOSTS_EQUIV, &st) < 0 && - stat(_PATH_SSH_HOSTS_EQUIV, &st) < 0) - return 0; - - /* If not logging in as superuser, try /etc/hosts.equiv and shosts.equiv. */ - if (pw->pw_uid != 0) { - 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(_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; - } - } - /* - * 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) { - 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)) { - 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); - - /* Check all .rhosts files (currently .shosts and .rhosts). */ - for (rhosts_file_index = 0; rhosts_files[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 (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. - */ - if (options.strict_modes && - ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || - (st.st_mode & 022) != 0)) { - logit("Rhosts authentication refused for %.100s: bad modes for %.200s", - pw->pw_name, 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) { - 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)) { - 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 the privileged uid. */ - 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; -} |