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/*
* libgit2 multi-pack-index fuzzer target.
*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include <stdio.h>
#include "git2.h"
#include "common.h"
#include "futils.h"
#include "hash.h"
#include "midx.h"
#include "standalone_driver.h"
int LLVMFuzzerInitialize(int *argc, char ***argv)
{
GIT_UNUSED(argc);
GIT_UNUSED(argv);
if (git_libgit2_init() < 0) {
fprintf(stderr, "Failed to initialize libgit2\n");
abort();
}
return 0;
}
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
git_midx_file idx = {{0}};
git_midx_entry e;
git_str midx_buf = GIT_STR_INIT;
unsigned char hash[GIT_HASH_SHA1_SIZE];
git_oid oid = GIT_OID_NONE;
bool append_hash = false;
if (size < 4)
return 0;
/*
* If the first byte in the stream has the high bit set, append the
* SHA1 hash so that the packfile is somewhat valid.
*/
append_hash = *data & 0x80;
/* Keep a 4-byte alignment to avoid unaligned accesses. */
data += 4;
size -= 4;
if (append_hash) {
if (git_str_init(&midx_buf, size + GIT_HASH_SHA1_SIZE) < 0)
goto cleanup;
if (git_hash_buf(hash, data, size, GIT_HASH_ALGORITHM_SHA1) < 0) {
fprintf(stderr, "Failed to compute the SHA1 hash\n");
abort();
}
memcpy(midx_buf.ptr, data, size);
memcpy(midx_buf.ptr + size, hash, GIT_HASH_SHA1_SIZE);
memcpy(oid.id, hash, GIT_OID_SHA1_SIZE);
} else {
git_str_attach_notowned(&midx_buf, (char *)data, size);
}
if (git_midx_parse(&idx, (const unsigned char *)git_str_cstr(&midx_buf), git_str_len(&midx_buf)) < 0)
goto cleanup;
/* Search for any oid, just to exercise that codepath. */
if (git_midx_entry_find(&e, &idx, &oid, GIT_OID_SHA1_HEXSIZE) < 0)
goto cleanup;
cleanup:
git_midx_close(&idx);
git_str_dispose(&midx_buf);
return 0;
}
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