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/*
* Dropbear SSH
*
* Copyright (c) 2005 Matt Johnston
* 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 "buffer.h"
#include "dbutil.h"
#include "session.h"
#include "ssh.h"
#include "runopts.h"
#if DROPBEAR_CLI_INTERACT_AUTH
static char* get_response(char* prompt)
{
FILE* tty = NULL;
char* response = NULL;
/* not a password, but a reasonable limit */
char buf[DROPBEAR_MAX_CLI_PASS];
char* ret = NULL;
fprintf(stderr, "%s", prompt);
tty = fopen(_PATH_TTY, "r");
if (tty) {
ret = fgets(buf, sizeof(buf), tty);
fclose(tty);
} else {
ret = fgets(buf, sizeof(buf), stdin);
}
if (ret == NULL) {
response = m_strdup("");
} else {
unsigned int buflen = strlen(buf);
/* fgets includes newlines */
if (buflen > 0 && buf[buflen-1] == '\n')
buf[buflen-1] = '\0';
response = m_strdup(buf);
}
m_burn(buf, sizeof(buf));
return response;
}
void recv_msg_userauth_info_request() {
char *name = NULL;
char *instruction = NULL;
unsigned int num_prompts = 0;
unsigned int i;
char *prompt = NULL;
unsigned int echo = 0;
char *response = NULL;
TRACE(("enter recv_msg_recv_userauth_info_request"))
/* Let the user know what password/host they are authing for */
if (!cli_ses.interact_request_received) {
fprintf(stderr, "Login for %s@%s\n", cli_opts.username,
cli_opts.remotehost);
}
cli_ses.interact_request_received = 1;
name = buf_getstring(ses.payload, NULL);
instruction = buf_getstring(ses.payload, NULL);
/* language tag */
buf_eatstring(ses.payload);
num_prompts = buf_getint(ses.payload);
if (num_prompts >= DROPBEAR_MAX_CLI_INTERACT_PROMPTS) {
dropbear_exit("Too many prompts received for keyboard-interactive");
}
/* we'll build the response as we go */
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_INFO_RESPONSE);
buf_putint(ses.writepayload, num_prompts);
if (strlen(name) > 0) {
cleantext(name);
fprintf(stderr, "%s", name);
}
m_free(name);
if (strlen(instruction) > 0) {
cleantext(instruction);
fprintf(stderr, "%s", instruction);
}
m_free(instruction);
for (i = 0; i < num_prompts; i++) {
unsigned int response_len = 0;
prompt = buf_getstring(ses.payload, NULL);
cleantext(prompt);
echo = buf_getbool(ses.payload);
if (!echo) {
char* p = getpass_or_cancel(prompt);
response = m_strdup(p);
m_burn(p, strlen(p));
} else {
response = get_response(prompt);
}
response_len = strlen(response);
buf_putstring(ses.writepayload, response, response_len);
m_burn(response, response_len);
m_free(prompt);
m_free(response);
}
encrypt_packet();
TRACE(("leave recv_msg_recv_userauth_info_request"))
}
void cli_auth_interactive() {
TRACE(("enter cli_auth_interactive"))
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);
/* username */
buf_putstring(ses.writepayload, cli_opts.username,
strlen(cli_opts.username));
/* service name */
buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION,
SSH_SERVICE_CONNECTION_LEN);
/* method */
buf_putstring(ses.writepayload, AUTH_METHOD_INTERACT,
AUTH_METHOD_INTERACT_LEN);
/* empty language tag */
buf_putstring(ses.writepayload, "", 0);
/* empty submethods */
buf_putstring(ses.writepayload, "", 0);
encrypt_packet();
cli_ses.interact_request_received = 0;
TRACE(("leave cli_auth_interactive"))
}
#endif /* DROPBEAR_CLI_INTERACT_AUTH */
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