upstream) and a number of security fixes which we had already backported. MFC after: 1 week
758 lines
22 KiB
C
758 lines
22 KiB
C
/* $OpenBSD: sshconnect1.c,v 1.76 2014/07/15 15:54:14 millert Exp $ */
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/*
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* Author: Tatu Ylonen <ylo@cs.hut.fi>
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* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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* All rights reserved
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* Code to connect to a remote host, and to perform the client side of the
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* login (authentication) dialog.
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*
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* As far as I am concerned, the code I have written for this software
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* can be used freely for any purpose. Any derived versions of this
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* software must be clearly marked as such, and if the derived work is
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* incompatible with the protocol description in the RFC file, it must be
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* called by a name other than "ssh" or "Secure Shell".
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*/
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#include "includes.h"
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <openssl/bn.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <signal.h>
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#include <pwd.h>
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#include "xmalloc.h"
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#include "ssh.h"
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#include "ssh1.h"
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#include "rsa.h"
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#include "buffer.h"
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#include "packet.h"
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#include "key.h"
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#include "cipher.h"
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#include "kex.h"
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#include "uidswap.h"
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#include "log.h"
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#include "misc.h"
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#include "readconf.h"
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#include "authfd.h"
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#include "sshconnect.h"
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#include "authfile.h"
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#include "canohost.h"
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#include "hostfile.h"
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#include "auth.h"
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#include "digest.h"
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/* Session id for the current session. */
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u_char session_id[16];
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u_int supported_authentications = 0;
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extern Options options;
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extern char *__progname;
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/*
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* Checks if the user has an authentication agent, and if so, tries to
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* authenticate using the agent.
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*/
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static int
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try_agent_authentication(void)
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{
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int type;
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char *comment;
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AuthenticationConnection *auth;
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u_char response[16];
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u_int i;
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Key *key;
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BIGNUM *challenge;
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/* Get connection to the agent. */
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auth = ssh_get_authentication_connection();
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if (!auth)
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return 0;
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if ((challenge = BN_new()) == NULL)
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fatal("try_agent_authentication: BN_new failed");
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/* Loop through identities served by the agent. */
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for (key = ssh_get_first_identity(auth, &comment, 1);
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key != NULL;
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key = ssh_get_next_identity(auth, &comment, 1)) {
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/* Try this identity. */
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debug("Trying RSA authentication via agent with '%.100s'", comment);
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free(comment);
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/* Tell the server that we are willing to authenticate using this key. */
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packet_start(SSH_CMSG_AUTH_RSA);
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packet_put_bignum(key->rsa->n);
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packet_send();
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packet_write_wait();
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/* Wait for server's response. */
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type = packet_read();
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/* The server sends failure if it doesn't like our key or
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does not support RSA authentication. */
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if (type == SSH_SMSG_FAILURE) {
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debug("Server refused our key.");
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key_free(key);
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continue;
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}
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/* Otherwise it should have sent a challenge. */
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if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
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packet_disconnect("Protocol error during RSA authentication: %d",
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type);
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packet_get_bignum(challenge);
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packet_check_eom();
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debug("Received RSA challenge from server.");
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/* Ask the agent to decrypt the challenge. */
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if (!ssh_decrypt_challenge(auth, key, challenge, session_id, 1, response)) {
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/*
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* The agent failed to authenticate this identifier
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* although it advertised it supports this. Just
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* return a wrong value.
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*/
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logit("Authentication agent failed to decrypt challenge.");
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explicit_bzero(response, sizeof(response));
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}
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key_free(key);
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debug("Sending response to RSA challenge.");
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/* Send the decrypted challenge back to the server. */
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packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
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for (i = 0; i < 16; i++)
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packet_put_char(response[i]);
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packet_send();
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packet_write_wait();
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/* Wait for response from the server. */
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type = packet_read();
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/* The server returns success if it accepted the authentication. */
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if (type == SSH_SMSG_SUCCESS) {
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ssh_close_authentication_connection(auth);
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BN_clear_free(challenge);
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debug("RSA authentication accepted by server.");
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return 1;
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}
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/* Otherwise it should return failure. */
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if (type != SSH_SMSG_FAILURE)
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packet_disconnect("Protocol error waiting RSA auth response: %d",
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type);
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}
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ssh_close_authentication_connection(auth);
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BN_clear_free(challenge);
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debug("RSA authentication using agent refused.");
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return 0;
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}
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/*
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* Computes the proper response to a RSA challenge, and sends the response to
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* the server.
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*/
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static void
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respond_to_rsa_challenge(BIGNUM * challenge, RSA * prv)
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{
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u_char buf[32], response[16];
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struct ssh_digest_ctx *md;
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int i, len;
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/* Decrypt the challenge using the private key. */
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/* XXX think about Bleichenbacher, too */
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if (rsa_private_decrypt(challenge, challenge, prv) != 0)
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packet_disconnect(
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"respond_to_rsa_challenge: rsa_private_decrypt failed");
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/* Compute the response. */
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/* The response is MD5 of decrypted challenge plus session id. */
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len = BN_num_bytes(challenge);
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if (len <= 0 || (u_int)len > sizeof(buf))
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packet_disconnect(
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"respond_to_rsa_challenge: bad challenge length %d", len);
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memset(buf, 0, sizeof(buf));
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BN_bn2bin(challenge, buf + sizeof(buf) - len);
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if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
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ssh_digest_update(md, buf, 32) < 0 ||
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ssh_digest_update(md, session_id, 16) < 0 ||
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ssh_digest_final(md, response, sizeof(response)) < 0)
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fatal("%s: md5 failed", __func__);
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ssh_digest_free(md);
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debug("Sending response to host key RSA challenge.");
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/* Send the response back to the server. */
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packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
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for (i = 0; i < 16; i++)
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packet_put_char(response[i]);
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packet_send();
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packet_write_wait();
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explicit_bzero(buf, sizeof(buf));
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explicit_bzero(response, sizeof(response));
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explicit_bzero(&md, sizeof(md));
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}
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/*
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* Checks if the user has authentication file, and if so, tries to authenticate
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* the user using it.
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*/
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static int
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try_rsa_authentication(int idx)
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{
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BIGNUM *challenge;
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Key *public, *private;
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char buf[300], *passphrase, *comment, *authfile;
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int i, perm_ok = 1, type, quit;
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public = options.identity_keys[idx];
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authfile = options.identity_files[idx];
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comment = xstrdup(authfile);
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debug("Trying RSA authentication with key '%.100s'", comment);
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/* Tell the server that we are willing to authenticate using this key. */
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packet_start(SSH_CMSG_AUTH_RSA);
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packet_put_bignum(public->rsa->n);
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packet_send();
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packet_write_wait();
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/* Wait for server's response. */
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type = packet_read();
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/*
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* The server responds with failure if it doesn't like our key or
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* doesn't support RSA authentication.
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*/
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if (type == SSH_SMSG_FAILURE) {
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debug("Server refused our key.");
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free(comment);
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return 0;
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}
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/* Otherwise, the server should respond with a challenge. */
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if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
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packet_disconnect("Protocol error during RSA authentication: %d", type);
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/* Get the challenge from the packet. */
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if ((challenge = BN_new()) == NULL)
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fatal("try_rsa_authentication: BN_new failed");
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packet_get_bignum(challenge);
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packet_check_eom();
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debug("Received RSA challenge from server.");
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/*
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* If the key is not stored in external hardware, we have to
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* load the private key. Try first with empty passphrase; if it
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* fails, ask for a passphrase.
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*/
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if (public->flags & SSHKEY_FLAG_EXT)
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private = public;
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else
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private = key_load_private_type(KEY_RSA1, authfile, "", NULL,
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&perm_ok);
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if (private == NULL && !options.batch_mode && perm_ok) {
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snprintf(buf, sizeof(buf),
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"Enter passphrase for RSA key '%.100s': ", comment);
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for (i = 0; i < options.number_of_password_prompts; i++) {
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passphrase = read_passphrase(buf, 0);
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if (strcmp(passphrase, "") != 0) {
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private = key_load_private_type(KEY_RSA1,
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authfile, passphrase, NULL, NULL);
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quit = 0;
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} else {
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debug2("no passphrase given, try next key");
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quit = 1;
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}
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explicit_bzero(passphrase, strlen(passphrase));
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free(passphrase);
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if (private != NULL || quit)
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break;
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debug2("bad passphrase given, try again...");
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}
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}
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/* We no longer need the comment. */
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free(comment);
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if (private == NULL) {
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if (!options.batch_mode && perm_ok)
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error("Bad passphrase.");
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/* Send a dummy response packet to avoid protocol error. */
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packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
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for (i = 0; i < 16; i++)
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packet_put_char(0);
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packet_send();
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packet_write_wait();
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/* Expect the server to reject it... */
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packet_read_expect(SSH_SMSG_FAILURE);
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BN_clear_free(challenge);
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return 0;
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}
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/* Compute and send a response to the challenge. */
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respond_to_rsa_challenge(challenge, private->rsa);
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/* Destroy the private key unless it in external hardware. */
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if (!(private->flags & SSHKEY_FLAG_EXT))
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key_free(private);
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/* We no longer need the challenge. */
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BN_clear_free(challenge);
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/* Wait for response from the server. */
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type = packet_read();
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if (type == SSH_SMSG_SUCCESS) {
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debug("RSA authentication accepted by server.");
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return 1;
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}
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if (type != SSH_SMSG_FAILURE)
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packet_disconnect("Protocol error waiting RSA auth response: %d", type);
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debug("RSA authentication refused.");
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return 0;
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}
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/*
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* Tries to authenticate the user using combined rhosts or /etc/hosts.equiv
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* authentication and RSA host authentication.
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*/
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static int
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try_rhosts_rsa_authentication(const char *local_user, Key * host_key)
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{
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int type;
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BIGNUM *challenge;
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debug("Trying rhosts or /etc/hosts.equiv with RSA host authentication.");
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/* Tell the server that we are willing to authenticate using this key. */
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packet_start(SSH_CMSG_AUTH_RHOSTS_RSA);
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packet_put_cstring(local_user);
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packet_put_int(BN_num_bits(host_key->rsa->n));
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packet_put_bignum(host_key->rsa->e);
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packet_put_bignum(host_key->rsa->n);
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packet_send();
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packet_write_wait();
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/* Wait for server's response. */
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type = packet_read();
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/* The server responds with failure if it doesn't admit our
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.rhosts authentication or doesn't know our host key. */
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if (type == SSH_SMSG_FAILURE) {
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debug("Server refused our rhosts authentication or host key.");
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return 0;
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}
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/* Otherwise, the server should respond with a challenge. */
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if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
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packet_disconnect("Protocol error during RSA authentication: %d", type);
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/* Get the challenge from the packet. */
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if ((challenge = BN_new()) == NULL)
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fatal("try_rhosts_rsa_authentication: BN_new failed");
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packet_get_bignum(challenge);
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packet_check_eom();
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debug("Received RSA challenge for host key from server.");
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/* Compute a response to the challenge. */
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respond_to_rsa_challenge(challenge, host_key->rsa);
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/* We no longer need the challenge. */
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BN_clear_free(challenge);
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/* Wait for response from the server. */
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type = packet_read();
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if (type == SSH_SMSG_SUCCESS) {
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debug("Rhosts or /etc/hosts.equiv with RSA host authentication accepted by server.");
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return 1;
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}
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if (type != SSH_SMSG_FAILURE)
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packet_disconnect("Protocol error waiting RSA auth response: %d", type);
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debug("Rhosts or /etc/hosts.equiv with RSA host authentication refused.");
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return 0;
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}
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/*
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* Tries to authenticate with any string-based challenge/response system.
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* Note that the client code is not tied to s/key or TIS.
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*/
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static int
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try_challenge_response_authentication(void)
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{
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int type, i;
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u_int clen;
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char prompt[1024];
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char *challenge, *response;
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debug("Doing challenge response authentication.");
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for (i = 0; i < options.number_of_password_prompts; i++) {
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/* request a challenge */
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packet_start(SSH_CMSG_AUTH_TIS);
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packet_send();
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packet_write_wait();
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type = packet_read();
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if (type != SSH_SMSG_FAILURE &&
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type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
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packet_disconnect("Protocol error: got %d in response "
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"to SSH_CMSG_AUTH_TIS", type);
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}
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if (type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
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debug("No challenge.");
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return 0;
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}
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challenge = packet_get_string(&clen);
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packet_check_eom();
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snprintf(prompt, sizeof prompt, "%s%s", challenge,
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strchr(challenge, '\n') ? "" : "\nResponse: ");
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free(challenge);
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if (i != 0)
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error("Permission denied, please try again.");
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if (options.cipher == SSH_CIPHER_NONE)
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logit("WARNING: Encryption is disabled! "
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"Response will be transmitted in clear text.");
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response = read_passphrase(prompt, 0);
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if (strcmp(response, "") == 0) {
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free(response);
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break;
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}
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packet_start(SSH_CMSG_AUTH_TIS_RESPONSE);
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ssh_put_password(response);
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explicit_bzero(response, strlen(response));
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free(response);
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packet_send();
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packet_write_wait();
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type = packet_read();
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if (type == SSH_SMSG_SUCCESS)
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return 1;
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if (type != SSH_SMSG_FAILURE)
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packet_disconnect("Protocol error: got %d in response "
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"to SSH_CMSG_AUTH_TIS_RESPONSE", type);
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}
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/* failure */
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return 0;
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}
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/*
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* Tries to authenticate with plain passwd authentication.
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*/
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static int
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try_password_authentication(char *prompt)
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{
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int type, i;
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char *password;
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debug("Doing password authentication.");
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if (options.cipher == SSH_CIPHER_NONE)
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logit("WARNING: Encryption is disabled! Password will be transmitted in clear text.");
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for (i = 0; i < options.number_of_password_prompts; i++) {
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if (i != 0)
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error("Permission denied, please try again.");
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password = read_passphrase(prompt, 0);
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packet_start(SSH_CMSG_AUTH_PASSWORD);
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ssh_put_password(password);
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explicit_bzero(password, strlen(password));
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free(password);
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packet_send();
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packet_write_wait();
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type = packet_read();
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if (type == SSH_SMSG_SUCCESS)
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return 1;
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if (type != SSH_SMSG_FAILURE)
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packet_disconnect("Protocol error: got %d in response to passwd auth", type);
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}
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/* failure */
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return 0;
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}
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/*
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* SSH1 key exchange
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*/
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void
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ssh_kex(char *host, struct sockaddr *hostaddr)
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{
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int i;
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BIGNUM *key;
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Key *host_key, *server_key;
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int bits, rbits;
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int ssh_cipher_default = SSH_CIPHER_3DES;
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u_char session_key[SSH_SESSION_KEY_LENGTH];
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u_char cookie[8];
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u_int supported_ciphers;
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u_int server_flags, client_flags;
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u_int32_t rnd = 0;
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debug("Waiting for server public key.");
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/* Wait for a public key packet from the server. */
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packet_read_expect(SSH_SMSG_PUBLIC_KEY);
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/* Get cookie from the packet. */
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for (i = 0; i < 8; i++)
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cookie[i] = packet_get_char();
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/* Get the public key. */
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server_key = key_new(KEY_RSA1);
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bits = packet_get_int();
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packet_get_bignum(server_key->rsa->e);
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packet_get_bignum(server_key->rsa->n);
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rbits = BN_num_bits(server_key->rsa->n);
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if (bits != rbits) {
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logit("Warning: Server lies about size of server public key: "
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"actual size is %d bits vs. announced %d.", rbits, bits);
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logit("Warning: This may be due to an old implementation of ssh.");
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}
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/* Get the host key. */
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host_key = key_new(KEY_RSA1);
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bits = packet_get_int();
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packet_get_bignum(host_key->rsa->e);
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packet_get_bignum(host_key->rsa->n);
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rbits = BN_num_bits(host_key->rsa->n);
|
|
if (bits != rbits) {
|
|
logit("Warning: Server lies about size of server host key: "
|
|
"actual size is %d bits vs. announced %d.", rbits, bits);
|
|
logit("Warning: This may be due to an old implementation of ssh.");
|
|
}
|
|
|
|
/* Get protocol flags. */
|
|
server_flags = packet_get_int();
|
|
packet_set_protocol_flags(server_flags);
|
|
|
|
supported_ciphers = packet_get_int();
|
|
supported_authentications = packet_get_int();
|
|
packet_check_eom();
|
|
|
|
debug("Received server public key (%d bits) and host key (%d bits).",
|
|
BN_num_bits(server_key->rsa->n), BN_num_bits(host_key->rsa->n));
|
|
|
|
if (verify_host_key(host, hostaddr, host_key) == -1)
|
|
fatal("Host key verification failed.");
|
|
|
|
client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN;
|
|
|
|
derive_ssh1_session_id(host_key->rsa->n, server_key->rsa->n, cookie, session_id);
|
|
|
|
/*
|
|
* Generate an encryption key for the session. The key is a 256 bit
|
|
* random number, interpreted as a 32-byte key, with the least
|
|
* significant 8 bits being the first byte of the key.
|
|
*/
|
|
for (i = 0; i < 32; i++) {
|
|
if (i % 4 == 0)
|
|
rnd = arc4random();
|
|
session_key[i] = rnd & 0xff;
|
|
rnd >>= 8;
|
|
}
|
|
|
|
/*
|
|
* According to the protocol spec, the first byte of the session key
|
|
* is the highest byte of the integer. The session key is xored with
|
|
* the first 16 bytes of the session id.
|
|
*/
|
|
if ((key = BN_new()) == NULL)
|
|
fatal("ssh_kex: BN_new failed");
|
|
if (BN_set_word(key, 0) == 0)
|
|
fatal("ssh_kex: BN_set_word failed");
|
|
for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
|
|
if (BN_lshift(key, key, 8) == 0)
|
|
fatal("ssh_kex: BN_lshift failed");
|
|
if (i < 16) {
|
|
if (BN_add_word(key, session_key[i] ^ session_id[i])
|
|
== 0)
|
|
fatal("ssh_kex: BN_add_word failed");
|
|
} else {
|
|
if (BN_add_word(key, session_key[i]) == 0)
|
|
fatal("ssh_kex: BN_add_word failed");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Encrypt the integer using the public key and host key of the
|
|
* server (key with smaller modulus first).
|
|
*/
|
|
if (BN_cmp(server_key->rsa->n, host_key->rsa->n) < 0) {
|
|
/* Public key has smaller modulus. */
|
|
if (BN_num_bits(host_key->rsa->n) <
|
|
BN_num_bits(server_key->rsa->n) + SSH_KEY_BITS_RESERVED) {
|
|
fatal("respond_to_rsa_challenge: host_key %d < server_key %d + "
|
|
"SSH_KEY_BITS_RESERVED %d",
|
|
BN_num_bits(host_key->rsa->n),
|
|
BN_num_bits(server_key->rsa->n),
|
|
SSH_KEY_BITS_RESERVED);
|
|
}
|
|
if (rsa_public_encrypt(key, key, server_key->rsa) != 0 ||
|
|
rsa_public_encrypt(key, key, host_key->rsa) != 0)
|
|
fatal("%s: rsa_public_encrypt failed", __func__);
|
|
} else {
|
|
/* Host key has smaller modulus (or they are equal). */
|
|
if (BN_num_bits(server_key->rsa->n) <
|
|
BN_num_bits(host_key->rsa->n) + SSH_KEY_BITS_RESERVED) {
|
|
fatal("respond_to_rsa_challenge: server_key %d < host_key %d + "
|
|
"SSH_KEY_BITS_RESERVED %d",
|
|
BN_num_bits(server_key->rsa->n),
|
|
BN_num_bits(host_key->rsa->n),
|
|
SSH_KEY_BITS_RESERVED);
|
|
}
|
|
if (rsa_public_encrypt(key, key, host_key->rsa) != 0 ||
|
|
rsa_public_encrypt(key, key, server_key->rsa) != 0)
|
|
fatal("%s: rsa_public_encrypt failed", __func__);
|
|
}
|
|
|
|
/* Destroy the public keys since we no longer need them. */
|
|
key_free(server_key);
|
|
key_free(host_key);
|
|
|
|
if (options.cipher == SSH_CIPHER_NOT_SET) {
|
|
if (cipher_mask_ssh1(1) & supported_ciphers & (1 << ssh_cipher_default))
|
|
options.cipher = ssh_cipher_default;
|
|
} else if (options.cipher == SSH_CIPHER_INVALID ||
|
|
!(cipher_mask_ssh1(1) & (1 << options.cipher))) {
|
|
logit("No valid SSH1 cipher, using %.100s instead.",
|
|
cipher_name(ssh_cipher_default));
|
|
options.cipher = ssh_cipher_default;
|
|
}
|
|
/* Check that the selected cipher is supported. */
|
|
if (!(supported_ciphers & (1 << options.cipher)))
|
|
fatal("Selected cipher type %.100s not supported by server.",
|
|
cipher_name(options.cipher));
|
|
|
|
debug("Encryption type: %.100s", cipher_name(options.cipher));
|
|
|
|
/* Send the encrypted session key to the server. */
|
|
packet_start(SSH_CMSG_SESSION_KEY);
|
|
packet_put_char(options.cipher);
|
|
|
|
/* Send the cookie back to the server. */
|
|
for (i = 0; i < 8; i++)
|
|
packet_put_char(cookie[i]);
|
|
|
|
/* Send and destroy the encrypted encryption key integer. */
|
|
packet_put_bignum(key);
|
|
BN_clear_free(key);
|
|
|
|
/* Send protocol flags. */
|
|
packet_put_int(client_flags);
|
|
|
|
/* Send the packet now. */
|
|
packet_send();
|
|
packet_write_wait();
|
|
|
|
debug("Sent encrypted session key.");
|
|
|
|
/* Set the encryption key. */
|
|
packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, options.cipher);
|
|
|
|
/*
|
|
* We will no longer need the session key here.
|
|
* Destroy any extra copies.
|
|
*/
|
|
explicit_bzero(session_key, sizeof(session_key));
|
|
|
|
/*
|
|
* Expect a success message from the server. Note that this message
|
|
* will be received in encrypted form.
|
|
*/
|
|
packet_read_expect(SSH_SMSG_SUCCESS);
|
|
|
|
debug("Received encrypted confirmation.");
|
|
}
|
|
|
|
/*
|
|
* Authenticate user
|
|
*/
|
|
void
|
|
ssh_userauth1(const char *local_user, const char *server_user, char *host,
|
|
Sensitive *sensitive)
|
|
{
|
|
int i, type;
|
|
|
|
if (supported_authentications == 0)
|
|
fatal("ssh_userauth1: server supports no auth methods");
|
|
|
|
/* Send the name of the user to log in as on the server. */
|
|
packet_start(SSH_CMSG_USER);
|
|
packet_put_cstring(server_user);
|
|
packet_send();
|
|
packet_write_wait();
|
|
|
|
/*
|
|
* The server should respond with success if no authentication is
|
|
* needed (the user has no password). Otherwise the server responds
|
|
* with failure.
|
|
*/
|
|
type = packet_read();
|
|
|
|
/* check whether the connection was accepted without authentication. */
|
|
if (type == SSH_SMSG_SUCCESS)
|
|
goto success;
|
|
if (type != SSH_SMSG_FAILURE)
|
|
packet_disconnect("Protocol error: got %d in response to SSH_CMSG_USER", type);
|
|
|
|
/*
|
|
* Try .rhosts or /etc/hosts.equiv authentication with RSA host
|
|
* authentication.
|
|
*/
|
|
if ((supported_authentications & (1 << SSH_AUTH_RHOSTS_RSA)) &&
|
|
options.rhosts_rsa_authentication) {
|
|
for (i = 0; i < sensitive->nkeys; i++) {
|
|
if (sensitive->keys[i] != NULL &&
|
|
sensitive->keys[i]->type == KEY_RSA1 &&
|
|
try_rhosts_rsa_authentication(local_user,
|
|
sensitive->keys[i]))
|
|
goto success;
|
|
}
|
|
}
|
|
/* Try RSA authentication if the server supports it. */
|
|
if ((supported_authentications & (1 << SSH_AUTH_RSA)) &&
|
|
options.rsa_authentication) {
|
|
/*
|
|
* Try RSA authentication using the authentication agent. The
|
|
* agent is tried first because no passphrase is needed for
|
|
* it, whereas identity files may require passphrases.
|
|
*/
|
|
if (try_agent_authentication())
|
|
goto success;
|
|
|
|
/* Try RSA authentication for each identity. */
|
|
for (i = 0; i < options.num_identity_files; i++)
|
|
if (options.identity_keys[i] != NULL &&
|
|
options.identity_keys[i]->type == KEY_RSA1 &&
|
|
try_rsa_authentication(i))
|
|
goto success;
|
|
}
|
|
/* Try challenge response authentication if the server supports it. */
|
|
if ((supported_authentications & (1 << SSH_AUTH_TIS)) &&
|
|
options.challenge_response_authentication && !options.batch_mode) {
|
|
if (try_challenge_response_authentication())
|
|
goto success;
|
|
}
|
|
/* Try password authentication if the server supports it. */
|
|
if ((supported_authentications & (1 << SSH_AUTH_PASSWORD)) &&
|
|
options.password_authentication && !options.batch_mode) {
|
|
char prompt[80];
|
|
|
|
snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
|
|
server_user, host);
|
|
if (try_password_authentication(prompt))
|
|
goto success;
|
|
}
|
|
/* All authentication methods have failed. Exit with an error message. */
|
|
fatal("Permission denied.");
|
|
/* NOTREACHED */
|
|
|
|
success:
|
|
return; /* need statement after label */
|
|
}
|