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/*
* Copyright (c) 2021 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.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#if defined(HAVE_STDINT_H)
# include <stdint.h>
#elif defined(HAVE_INTTYPES_H)
# include <inttypes.h>
#endif
#include <sudoers.h>
static int fuzz_printf(int msg_type, const char * restrict fmt, ...);
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
/* Required to link with parser. */
sudo_printf_t sudo_printf = fuzz_printf;
FILE *
open_sudoers(const char *file, char **outfile, bool doedit, bool *keepopen)
{
/*
* If we allow the fuzzer to choose include paths it will
* include random files in the file system.
* This leads to bug reports that cannot be reproduced.
*/
return NULL;
}
static int
fuzz_printf(int msg_type, const char * restrict fmt, ...)
{
return 0;
}
bool
init_envtables(void)
{
return true;
}
int
set_cmnd_path(struct sudoers_context *ctx, const char *runchroot)
{
/* Cannot return FOUND without also setting ctx->user.cmnd to a new value. */
return NOT_FOUND;
}
static FILE *
open_data(const uint8_t *data, size_t size)
{
#ifdef HAVE_FMEMOPEN
/* Operate in-memory. */
return fmemopen((void *)data, size, "r");
#else
char tempfile[] = "/tmp/ldif.XXXXXX";
size_t nwritten;
int fd;
/* Use (unlinked) temporary file. */
fd = mkstemp(tempfile);
if (fd == -1)
return NULL;
unlink(tempfile);
nwritten = write(fd, data, size);
if (nwritten != size) {
close(fd);
return NULL;
}
lseek(fd, 0, SEEK_SET);
return fdopen(fd, "r");
#endif
}
static int
fuzz_conversation(int num_msgs, const struct sudo_conv_message msgs[],
struct sudo_conv_reply replies[], struct sudo_conv_callback *callback)
{
int n;
for (n = 0; n < num_msgs; n++) {
const struct sudo_conv_message *msg = &msgs[n];
switch (msg->msg_type & 0xff) {
case SUDO_CONV_PROMPT_ECHO_ON:
case SUDO_CONV_PROMPT_MASK:
case SUDO_CONV_PROMPT_ECHO_OFF:
/* input not supported */
return -1;
case SUDO_CONV_ERROR_MSG:
case SUDO_CONV_INFO_MSG:
/* no output for fuzzers */
break;
default:
return -1;
}
}
return 0;
}
int
LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
struct sudoers_context ctx = { { NULL } };
struct sudoers_parse_tree parse_tree;
FILE *fp;
/* Don't waste time fuzzing tiny inputs. */
if (size < 5)
return 0;
fp = open_data(data, size);
if (fp == NULL)
return 0;
initprogname("fuzz_sudoers_ldif");
sudoers_debug_register(getprogname(), NULL);
if (getenv("SUDO_FUZZ_VERBOSE") == NULL)
sudo_warn_set_conversation(fuzz_conversation);
/* Initialize defaults and parse LDIF-format sudoers. */
init_defaults();
init_parse_tree(&parse_tree, NULL, NULL, &ctx, NULL);
sudoers_parse_ldif(&parse_tree, fp, "ou=SUDOers,dc=sudo,dc=ws", true);
/* Cleanup. */
free_parse_tree(&parse_tree);
fclose(fp);
sudoers_debug_deregister();
fflush(stdout);
return 0;
}
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