blob: 2500a25ff808d966b7ce193dacef5d3030115016 [file] [log] [blame]
/*
* Dropbear SSH
*
* Copyright (c) 2002,2003 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"
#ifdef ENABLE_CLI_PASSWORD_AUTH
#ifdef ENABLE_CLI_ASKPASS_HELPER
/* Returns 1 if we want to use the askpass program, 0 otherwise */
static int want_askpass()
{
char* askpass_prog = NULL;
askpass_prog = getenv("SSH_ASKPASS");
return askpass_prog && !isatty(STDIN_FILENO) && getenv("DISPLAY");
}
/* returns a statically allocated password from a helper app, or NULL
* on failure */
static char *gui_getpass(const char *prompt) {
pid_t pid;
int p[2], maxlen, len, status;
static char buf[DROPBEAR_MAX_CLI_PASS + 1];
char* helper = NULL;
TRACE(("enter gui_getpass"))
helper = getenv("SSH_ASKPASS");
if (!helper)
{
TRACE(("leave gui_getpass: no askpass program"))
return NULL;
}
if (pipe(p) < 0) {
TRACE(("error creating child pipe"))
return NULL;
}
pid = fork();
if (pid < 0) {
TRACE(("fork error"))
return NULL;
}
if (!pid) {
/* child */
close(p[0]);
if (dup2(p[1], STDOUT_FILENO) < 0) {
TRACE(("error redirecting stdout"))
exit(1);
}
close(p[1]);
execlp(helper, helper, prompt, (char *)0);
TRACE(("execlp error"))
exit(1);
}
close(p[1]);
maxlen = sizeof(buf);
while (maxlen > 0) {
len = read(p[0], buf + sizeof(buf) - maxlen, maxlen);
if (len > 0) {
maxlen -= len;
} else {
if (errno != EINTR)
break;
}
}
close(p[0]);
while (waitpid(pid, &status, 0) < 0 && errno == EINTR)
;
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
return(NULL);
len = sizeof(buf) - maxlen;
buf[len] = '\0';
if (len > 0 && buf[len - 1] == '\n')
buf[len - 1] = '\0';
TRACE(("leave gui_getpass"))
return(buf);
}
#endif /* ENABLE_CLI_ASKPASS_HELPER */
void cli_auth_password() {
char* password = NULL;
char prompt[80];
TRACE(("enter cli_auth_password"))
CHECKCLEARTOWRITE();
snprintf(prompt, sizeof(prompt), "%s@%s's password: ",
cli_opts.username, cli_opts.remotehost);
#ifdef ENABLE_CLI_ASKPASS_HELPER
if (want_askpass())
password = gui_getpass(prompt);
else
#endif
password = getpass_or_cancel(prompt);
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, AUTH_METHOD_PASSWORD,
AUTH_METHOD_PASSWORD_LEN);
buf_putbyte(ses.writepayload, 0); /* FALSE - so says the spec */
buf_putstring(ses.writepayload, password, strlen(password));
encrypt_packet();
m_burn(password, strlen(password));
TRACE(("leave cli_auth_password"))
}
#endif /* ENABLE_CLI_PASSWORD_AUTH */