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/*
* Dropbear SSH
*
* Copyright (c) 2002,2003 Matt Johnston
* Copyright (c) 2004 by Mihnea Stoenescu
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE. */
#include "includes.h"
#include "session.h"
#include "auth.h"
#include "dbutil.h"
#include "buffer.h"
#include "ssh.h"
#include "packet.h"
#include "runopts.h"
void cli_authinitialise() {
memset(&ses.authstate, 0, sizeof(ses.authstate));
}
/* Send a "none" auth request to get available methods */
void cli_auth_getmethods() {
TRACE(("enter cli_auth_getmethods"));
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);
buf_putstring(ses.writepayload, cli_opts.username,
strlen(cli_opts.username));
buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION,
SSH_SERVICE_CONNECTION_LEN);
buf_putstring(ses.writepayload, "none", 4); /* 'none' method */
encrypt_packet();
TRACE(("leave cli_auth_getmethods"));
}
void recv_msg_userauth_banner() {
unsigned char* banner = NULL;
unsigned int bannerlen;
unsigned int i, linecount;
TRACE(("enter recv_msg_userauth_banner"));
if (ses.authstate.authdone) {
TRACE(("leave recv_msg_userauth_banner: banner after auth done"));
return;
}
banner = buf_getstring(ses.payload, &bannerlen);
buf_eatstring(ses.payload); /* The language string */
if (bannerlen > MAX_BANNER_SIZE) {
TRACE(("recv_msg_userauth_banner: bannerlen too long: %d", bannerlen));
goto out;
}
cleantext(banner);
/* Limit to 25 lines */
linecount = 1;
for (i = 0; i < bannerlen; i++) {
if (banner[i] == '\n') {
if (linecount >= MAX_BANNER_LINES) {
banner[i] = '\0';
break;
}
linecount++;
}
}
printf("%s\n", banner);
out:
m_free(banner);
TRACE(("leave recv_msg_userauth_banner"));
}
void recv_msg_userauth_failure() {
unsigned char * methods = NULL;
unsigned char * tok = NULL;
unsigned int methlen = 0;
unsigned int partial = 0;
unsigned int i = 0;
TRACE(("<- MSG_USERAUTH_FAILURE"));
TRACE(("enter recv_msg_userauth_failure"));
if (cli_ses.state != USERAUTH_REQ_SENT) {
/* Perhaps we should be more fatal? */
TRACE(("But we didn't send a userauth request!!!!!!"));
return;
}
#ifdef ENABLE_CLI_PUBKEY_AUTH
/* If it was a pubkey auth request, we should cross that key
* off the list. */
if (cli_ses.lastauthtype == AUTH_TYPE_PUBKEY) {
cli_pubkeyfail();
}
#endif
methods = buf_getstring(ses.payload, &methlen);
partial = buf_getbyte(ses.payload);
if (partial) {
dropbear_log(LOG_INFO, "Authentication partially succeeded, more attempts required");
} else {
ses.authstate.failcount++;
}
TRACE(("Methods (len %d): '%s'", methlen, methods));
ses.authstate.authdone=0;
ses.authstate.authtypes=0;
/* Split with nulls rather than commas */
for (i = 0; i < methlen; i++) {
if (methods[i] == ',') {
methods[i] = '\0';
}
}
tok = methods; /* tok stores the next method we'll compare */
for (i = 0; i <= methlen; i++) {
if (methods[i] == '\0') {
TRACE(("auth method '%s'", tok));
#ifdef ENABLE_CLI_PUBKEY_AUTH
if (strncmp(AUTH_METHOD_PUBKEY, tok,
AUTH_METHOD_PUBKEY_LEN) == 0) {
ses.authstate.authtypes |= AUTH_TYPE_PUBKEY;
}
#endif
#ifdef ENABLE_CLI_PASSWORD_AUTH
if (strncmp(AUTH_METHOD_PASSWORD, tok,
AUTH_METHOD_PASSWORD_LEN) == 0) {
ses.authstate.authtypes |= AUTH_TYPE_PASSWORD;
}
#endif
tok = &methods[i+1]; /* Must make sure we don't use it after the
last loop, since it'll point to something
undefined */
}
}
cli_ses.state = USERAUTH_FAIL_RCVD;
TRACE(("leave recv_msg_userauth_failure"));
}
void recv_msg_userauth_success() {
TRACE(("received msg_userauth_success"));
ses.authstate.authdone = 1;
cli_ses.state = USERAUTH_SUCCESS_RCVD;
}
void cli_auth_try() {
TRACE(("enter cli_auth_try"));
int finished = 0;
CHECKCLEARTOWRITE();
/* XXX We hardcode that we try a pubkey first */
#ifdef ENABLE_CLI_PUBKEY_AUTH
if (ses.authstate.authtypes & AUTH_TYPE_PUBKEY) {
finished = cli_auth_pubkey();
cli_ses.lastauthtype = AUTH_TYPE_PUBKEY;
}
#endif
#ifdef ENABLE_CLI_PASSWORD_AUTH
if (!finished && ses.authstate.authtypes & AUTH_TYPE_PASSWORD) {
finished = cli_auth_password();
cli_ses.lastauthtype = AUTH_TYPE_PASSWORD;
}
#endif
if (!finished) {
dropbear_exit("No auth methods could be used.");
}
TRACE(("leave cli_auth_try"));
}
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