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Diffstat (limited to 'auth-rh-rsa.c')
-rw-r--r-- | auth-rh-rsa.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/auth-rh-rsa.c b/auth-rh-rsa.c new file mode 100644 index 0000000..eca7502 --- /dev/null +++ b/auth-rh-rsa.c @@ -0,0 +1,100 @@ +/* $OpenBSD: auth-rh-rsa.c,v 1.42 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 or /etc/hosts.equiv authentication combined with RSA host + * authentication. + * + * 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 <pwd.h> +#include <stdarg.h> + +#include "packet.h" +#include "uidswap.h" +#include "log.h" +#include "buffer.h" +#include "servconf.h" +#include "key.h" +#include "hostfile.h" +#include "pathnames.h" +#include "auth.h" +#include "canohost.h" +#ifdef GSSAPI +#include "ssh-gss.h" +#endif +#include "monitor_wrap.h" + +/* import */ +extern ServerOptions options; + +int +auth_rhosts_rsa_key_allowed(struct passwd *pw, char *cuser, char *chost, + Key *client_host_key) +{ + HostStatus host_status; + + /* Check if we would accept it using rhosts authentication. */ + if (!auth_rhosts(pw, cuser)) + return 0; + + host_status = check_key_in_hostfiles(pw, client_host_key, + chost, _PATH_SSH_SYSTEM_HOSTFILE, + options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE); + + return (host_status == HOST_OK); +} + +/* + * Tries to authenticate the user using the .rhosts file and the host using + * its host key. Returns true if authentication succeeds. + */ +int +auth_rhosts_rsa(Authctxt *authctxt, char *cuser, Key *client_host_key) +{ + char *chost; + struct passwd *pw = authctxt->pw; + + debug("Trying rhosts with RSA host authentication for client user %.100s", + cuser); + + if (!authctxt->valid || client_host_key == NULL || + client_host_key->rsa == NULL) + return 0; + + chost = (char *)get_canonical_hostname(options.use_dns); + debug("Rhosts RSA authentication: canonical host %.900s", chost); + + if (!PRIVSEP(auth_rhosts_rsa_key_allowed(pw, cuser, chost, client_host_key))) { + debug("Rhosts with RSA host authentication denied: unknown or invalid host key"); + packet_send_debug("Your host key cannot be verified: unknown or invalid host key."); + return 0; + } + /* A matching host key was found and is known. */ + + /* Perform the challenge-response dialog with the client for the host key. */ + if (!auth_rsa_challenge_dialog(client_host_key)) { + logit("Client on %.800s failed to respond correctly to host authentication.", + chost); + return 0; + } + /* + * We have authenticated the user using .rhosts or /etc/hosts.equiv, + * and the host using RSA. We accept the authentication. + */ + + verbose("Rhosts with RSA host authentication accepted for %.100s, %.100s on %.700s.", + pw->pw_name, cuser, chost); + packet_send_debug("Rhosts with RSA host authentication accepted."); + return 1; +} |