1 /* $OpenBSD: auth-rh-rsa.c,v 1.45 2016/03/07 19:02:43 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * Rhosts or /etc/hosts.equiv authentication combined with RSA host
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
20 #include <sys/types.h>
33 #include "pathnames.h"
39 #include "monitor_wrap.h"
42 extern ServerOptions options;
45 auth_rhosts_rsa_key_allowed(struct passwd *pw, const char *cuser,
46 const char *chost, Key *client_host_key)
48 HostStatus host_status;
50 if (auth_key_is_revoked(client_host_key))
53 /* Check if we would accept it using rhosts authentication. */
54 if (!auth_rhosts(pw, cuser))
57 host_status = check_key_in_hostfiles(pw, client_host_key,
58 chost, _PATH_SSH_SYSTEM_HOSTFILE,
59 options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE);
61 return (host_status == HOST_OK);
65 * Tries to authenticate the user using the .rhosts file and the host using
66 * its host key. Returns true if authentication succeeds.
69 auth_rhosts_rsa(Authctxt *authctxt, char *cuser, Key *client_host_key)
71 struct ssh *ssh = active_state; /* XXX */
73 struct passwd *pw = authctxt->pw;
75 debug("Trying rhosts with RSA host authentication for client user %.100s",
78 if (!authctxt->valid || client_host_key == NULL ||
79 client_host_key->rsa == NULL)
82 chost = auth_get_canonical_hostname(ssh, options.use_dns);
83 debug("Rhosts RSA authentication: canonical host %.900s", chost);
85 if (!PRIVSEP(auth_rhosts_rsa_key_allowed(pw, cuser, chost, client_host_key))) {
86 debug("Rhosts with RSA host authentication denied: unknown or invalid host key");
87 packet_send_debug("Your host key cannot be verified: unknown or invalid host key.");
90 /* A matching host key was found and is known. */
92 /* Perform the challenge-response dialog with the client for the host key. */
93 if (!auth_rsa_challenge_dialog(client_host_key)) {
94 logit("Client on %.800s failed to respond correctly to host authentication.",
99 * We have authenticated the user using .rhosts or /etc/hosts.equiv,
100 * and the host using RSA. We accept the authentication.
103 verbose("Rhosts with RSA host authentication accepted for %.100s, %.100s on %.700s.",
104 pw->pw_name, cuser, chost);
105 packet_send_debug("Rhosts with RSA host authentication accepted.");
109 #endif /* WITH_SSH1 */