/* * auth1.c - authentication with SSH-1 protocol * * This file is part of the SSH Library * * Copyright (c) 2005-2008 by Aris Adamantiadis * * The SSH Library is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or (at your * option) any later version. * * The SSH Library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with the SSH Library; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ #include "config.h" #include #include #include "libssh/priv.h" #include "libssh/ssh1.h" #include "libssh/buffer.h" #include "libssh/packet.h" #include "libssh/session.h" #include "libssh/string.h" #ifdef WITH_SSH1 static int wait_auth1_status(ssh_session session) { /* wait for a packet */ if (packet_read(session) != SSH_OK) { return SSH_AUTH_ERROR; } if(packet_translate(session) != SSH_OK) { return SSH_AUTH_ERROR; } switch(session->in_packet.type) { case SSH_SMSG_SUCCESS: return SSH_AUTH_SUCCESS; case SSH_SMSG_FAILURE: return SSH_AUTH_DENIED; } ssh_set_error(session, SSH_FATAL, "Was waiting for a SUCCESS or " "FAILURE, got %d", session->in_packet.type); return SSH_AUTH_ERROR; } static int send_username(ssh_session session, const char *username) { ssh_string user = NULL; /* returns SSH_AUTH_SUCCESS or SSH_AUTH_DENIED */ if(session->auth_service_asked) { return session->auth_service_asked; } if (!username) { if(!(username = session->username)) { if (ssh_options_set(session, SSH_OPTIONS_USER, NULL) < 0) { return session->auth_service_asked = SSH_AUTH_ERROR; } else { username = session->username; } } } user = string_from_char(username); if (user == NULL) { return SSH_AUTH_ERROR; } if (buffer_add_u8(session->out_buffer, SSH_CMSG_USER) < 0) { string_free(user); return SSH_AUTH_ERROR; } if (buffer_add_ssh_string(session->out_buffer, user) < 0) { string_free(user); return SSH_AUTH_ERROR; } string_free(user); if (packet_send(session) != SSH_OK) { return SSH_AUTH_ERROR; } session->auth_service_asked = wait_auth1_status(session); return session->auth_service_asked; } /* use the "none" authentication question */ int ssh_userauth1_none(ssh_session session, const char *username){ return send_username(session, username); } /* int ssh_userauth_offer_pubkey(ssh_session session, char *username,int type, ssh_string publickey){ ssh_string user; ssh_string service; ssh_string method; ssh_string algo; int err=SSH_AUTH_ERROR; if(!username) if(!(username=session->options->username)){ if(options_default_username(session->options)) return SSH_AUTH_ERROR; else username=session->options->username; } if(ask_userauth(session)) return SSH_AUTH_ERROR; user=string_from_char(username); service=string_from_char("ssh-connection"); method=string_from_char("publickey"); algo=string_from_char(ssh_type_to_char(type)); packet_clear_out(session); buffer_add_u8(session->out_buffer,SSH2_MSG_USERAUTH_REQUEST); buffer_add_ssh_string(session->out_buffer,user); buffer_add_ssh_string(session->out_buffer,service); buffer_add_ssh_string(session->out_buffer,method); buffer_add_u8(session->out_buffer,0); buffer_add_ssh_string(session->out_buffer,algo); buffer_add_ssh_string(session->out_buffer,publickey); packet_send(session); err=wait_auth_status(session,0); free(user); free(method); free(service); free(algo); return err; } */ /** \internal * \todo implement ssh1 public key */ int ssh_userauth1_offer_pubkey(ssh_session session, const char *username, int type, ssh_string pubkey) { (void) session; (void) username; (void) type; (void) pubkey; return SSH_AUTH_DENIED; } /* int ssh_userauth_pubkey(ssh_session session, char *username, ssh_string publickey, ssh_private_key privatekey){ ssh_string user; ssh_string service; ssh_string method; ssh_string algo; ssh_string sign; int err=SSH_AUTH_ERROR; if(!username) if(!(username=session->options->username)){ if(options_default_username(session->options)) return err; else username=session->options->username; } if(ask_userauth(session)) return err; user=string_from_char(username); service=string_from_char("ssh-connection"); method=string_from_char("publickey"); algo=string_from_char(ssh_type_to_char(privatekey->type)); */ /* we said previously the public key was accepted */ /* packet_clear_out(session); buffer_add_u8(session->out_buffer,SSH2_MSG_USERAUTH_REQUEST); buffer_add_ssh_string(session->out_buffer,user); buffer_add_ssh_string(session->out_buffer,service); buffer_add_ssh_string(session->out_buffer,method); buffer_add_u8(session->out_buffer,1); buffer_add_ssh_string(session->out_buffer,algo); buffer_add_ssh_string(session->out_buffer,publickey); sign=ssh_do_sign(session,session->out_buffer,privatekey); if(sign){ buffer_add_ssh_string(session->out_buffer,sign); free(sign); packet_send(session); err=wait_auth_status(session,0); } free(user); free(service); free(method); free(algo); return err; } */ int ssh_userauth1_password(ssh_session session, const char *username, const char *password) { ssh_string pwd = NULL; int rc; rc = send_username(session, username); if (rc != SSH_AUTH_DENIED) { return rc; } /* we trick a bit here. A known flaw in SSH1 protocol is that it's * easy to guess password sizes. * not that sure ... */ /* XXX fix me here ! */ /* cisco IOS doesn't like when a password is followed by zeroes and random pad. */ if(1 || strlen(password) >= 128) { /* not risky to disclose the size of such a big password .. */ pwd = string_from_char(password); if (pwd == NULL) { return SSH_AUTH_ERROR; } } else { /* fill the password string from random things. the strcpy * ensure there is at least a nul byte after the password. * most implementation won't see the garbage at end. * why garbage ? because nul bytes will be compressed by * gzip and disclose password len. */ pwd = string_new(128); if (pwd == NULL) { return SSH_AUTH_ERROR; } ssh_get_random( pwd->string, 128, 0); strcpy((char *) pwd->string, password); } if (buffer_add_u8(session->out_buffer, SSH_CMSG_AUTH_PASSWORD) < 0) { string_burn(pwd); string_free(pwd); return SSH_AUTH_ERROR; } if (buffer_add_ssh_string(session->out_buffer, pwd) < 0) { string_burn(pwd); string_free(pwd); return SSH_AUTH_ERROR; } string_burn(pwd); string_free(pwd); if (packet_send(session) != SSH_OK) { return SSH_AUTH_ERROR; } return wait_auth1_status(session); } #endif /* WITH_SSH1 */ /* vim: set ts=2 sw=2 et cindent: */