Files
sudo/src/conversation.c
Todd C. Miller 4833ac0f01 Avoid passing sudo_term_is_raw() -1 for the fd.
Coverity CID 330472
Coverity CID 330468
2023-11-02 14:17:51 -06:00

240 lines
6.5 KiB
C

/*
* SPDX-License-Identifier: ISC
*
* Copyright (c) 1999-2005, 2007-2012 Todd C. Miller <Todd.Miller@sudo.ws>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F39502-99-1-0512.
*/
/*
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <sudo.h>
#include <sudo_plugin.h>
#include <sudo_plugin_int.h>
/*
* Sudo conversation function.
*/
int
sudo_conversation(int num_msgs, const struct sudo_conv_message msgs[],
struct sudo_conv_reply replies[], struct sudo_conv_callback *callback)
{
const int conv_debug_instance = sudo_debug_get_active_instance();
char *pass;
int n;
sudo_debug_set_active_instance(sudo_debug_instance);
for (n = 0; n < num_msgs; n++) {
const struct sudo_conv_message *msg = &msgs[n];
unsigned int flags = tgetpass_flags;
FILE *fp = stdout;
if (replies != NULL)
replies[n].reply = NULL;
switch (msg->msg_type & 0xff) {
case SUDO_CONV_PROMPT_ECHO_ON:
SET(flags, TGP_ECHO);
goto read_pass;
case SUDO_CONV_PROMPT_MASK:
SET(flags, TGP_MASK);
FALLTHROUGH;
case SUDO_CONV_PROMPT_ECHO_OFF:
if (ISSET(msg->msg_type, SUDO_CONV_PROMPT_ECHO_OK))
SET(flags, TGP_NOECHO_TRY);
read_pass:
/* Read the password unless interrupted. */
if (replies == NULL)
goto err;
pass = tgetpass(msg->msg, msg->timeout, flags, callback);
if (pass == NULL)
goto err;
replies[n].reply = strdup(pass);
if (replies[n].reply == NULL) {
sudo_fatalx_nodebug(U_("%s: %s"), "sudo_conversation",
U_("unable to allocate memory"));
}
explicit_bzero(pass, strlen(pass));
break;
case SUDO_CONV_ERROR_MSG:
fp = stderr;
FALLTHROUGH;
case SUDO_CONV_INFO_MSG:
if (msg->msg != NULL) {
size_t len = strlen(msg->msg);
const char *crnl = NULL;
bool written = false;
int ttyfd = -1;
bool raw_tty = false;
if (ISSET(msg->msg_type, SUDO_CONV_PREFER_TTY) &&
!ISSET(flags, TGP_STDIN)) {
ttyfd = open(_PATH_TTY, O_WRONLY);
if (ttyfd != -1)
raw_tty = sudo_term_is_raw(ttyfd);
} else {
raw_tty = sudo_term_is_raw(fileno(fp));
}
if (len != 0 && raw_tty) {
/* Convert nl -> cr nl in case tty is in raw mode. */
if (msg->msg[len - 1] == '\n') {
if (len == 1 || msg->msg[len - 2] != '\r') {
len--;
crnl = "\r\n";
}
}
}
if (ttyfd != -1) {
/* Try writing to tty but fall back to fp on error. */
if ((len == 0 || write(ttyfd, msg->msg, len) != -1) &&
(crnl == NULL || write(ttyfd, crnl, 2) != -1)) {
written = true;
}
close(ttyfd);
}
if (!written) {
if (len != 0 && fwrite(msg->msg, 1, len, fp) == 0)
goto err;
if (crnl != NULL && fwrite(crnl, 1, 2, fp) == 0)
goto err;
}
}
break;
default:
goto err;
}
}
sudo_debug_set_active_instance(conv_debug_instance);
return 0;
err:
/* Zero and free allocated memory and return an error. */
if (replies != NULL) {
do {
struct sudo_conv_reply *repl = &replies[n];
if (repl->reply == NULL)
continue;
freezero(repl->reply, strlen(repl->reply));
repl->reply = NULL;
} while (n-- > 0);
}
sudo_debug_set_active_instance(conv_debug_instance);
return -1;
}
int
sudo_conversation_1_7(int num_msgs, const struct sudo_conv_message msgs[],
struct sudo_conv_reply replies[])
{
return sudo_conversation(num_msgs, msgs, replies, NULL);
}
int
sudo_conversation_printf(int msg_type, const char * restrict fmt, ...)
{
FILE *ttyfp = NULL;
FILE *fp = stdout;
char fmt2[1024];
char sbuf[8192];
char *buf = sbuf;
va_list ap;
int len;
const int conv_debug_instance = sudo_debug_get_active_instance();
sudo_debug_set_active_instance(sudo_debug_instance);
if (ISSET(msg_type, SUDO_CONV_PREFER_TTY) &&
!ISSET(tgetpass_flags, TGP_STDIN)) {
/* Try writing to /dev/tty first. */
ttyfp = fopen(_PATH_TTY, "w");
}
switch (msg_type & 0xff) {
case SUDO_CONV_ERROR_MSG:
fp = stderr;
FALLTHROUGH;
case SUDO_CONV_INFO_MSG:
/* Convert nl -> cr nl in case tty is in raw mode. */
if (sudo_term_is_raw(fileno(ttyfp ? ttyfp : fp))) {
size_t fmtlen = strlen(fmt);
if (fmtlen < sizeof(fmt2) - 1 && fmtlen && fmt[fmtlen - 1] == '\n') {
if (fmtlen == 1) {
/* Convert bare newline -> \r\n. */
len = (int)fwrite("\r\n", 1, 2, ttyfp ? ttyfp : fp);
if (len != 2)
len = -1;
break;
}
if (fmt[fmtlen - 2] != '\r') {
/* Convert trailing \n -> \r\n. */
memcpy(fmt2, fmt, fmtlen - 1);
fmt2[fmtlen - 1] = '\r';
fmt2[fmtlen ] = '\n';
fmt2[fmtlen + 1] = '\0';
fmt = fmt2;
}
}
}
/*
* We use vsnprintf() instead of vfprintf() here to avoid
* problems on systems where the system printf(3) is not
* C99-compliant. We use our own snprintf() on such systems.
*/
va_start(ap, fmt);
len = vsnprintf(sbuf, sizeof(sbuf), fmt, ap);
va_end(ap);
if (len < 0 || len >= ssizeof(sbuf)) {
/* Try again with a dynamically-sized buffer. */
va_start(ap, fmt);
len = vasprintf(&buf, fmt, ap);
va_end(ap);
}
if (len != -1) {
if (fwrite(buf, 1, len, ttyfp ? ttyfp : fp) == 0)
len = -1;
if (buf != sbuf)
free(buf);
}
break;
default:
len = -1;
errno = EINVAL;
break;
}
if (ttyfp != NULL)
fclose(ttyfp);
sudo_debug_set_active_instance(conv_debug_instance);
return len;
}