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/*
* Copyright 2022 Jakub Jelen <jjelen@redhat.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define LIBSSH_STATIC 1
#include "libssh/libssh.h"
#include "knownhosts.c"
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
char *hostname = NULL;
const uint8_t *hostname_end = NULL;
size_t hostname_len = 0;
char filename[256];
struct ssh_list *entries = NULL;
struct ssh_iterator *it = NULL;
FILE *fp = NULL;
/* Interpret the first part of the string (until the first NULL byte)
* as a hostname we are searching for in the file */
hostname_end = memchr(data, '\0', size);
if (hostname_end == NULL) {
return 1;
}
hostname_len = hostname_end - data + 1;
if (hostname_len > 253) {
/* This is the maximum valid length of a hostname */
return 1;
}
hostname = malloc(hostname_len);
if (hostname == NULL) {
return 1;
}
memcpy(hostname, data, hostname_len);
snprintf(filename, sizeof(filename), "/tmp/libfuzzer.%d", getpid());
fp = fopen(filename, "wb");
if (!fp) {
free(hostname);
return 1;
}
fwrite(data + hostname_len, size - hostname_len, 1, fp);
fclose(fp);
ssh_init();
ssh_known_hosts_read_entries(hostname, filename, &entries);
for (it = ssh_list_get_iterator(entries);
it != NULL;
it = ssh_list_get_iterator(entries)) {
struct ssh_knownhosts_entry *entry = NULL;
entry = ssh_iterator_value(struct ssh_knownhosts_entry *, it);
ssh_knownhosts_entry_free(entry);
ssh_list_remove(entries, it);
}
ssh_list_free(entries);
ssh_finalize();
free(hostname);
unlink(filename);
return 0;
}
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