contrib/fuzz/xdiff.cc
author Matt Harbison <matt_harbison@yahoo.com>
Fri, 06 Apr 2018 11:13:47 -0400
changeset 37766 925707ac2855
parent 36765 04d64163039a
child 38173 fa0ddd5e8fff
permissions -rw-r--r--
lfs: add the 'Authorization' property to the Batch API response, if present The client copies all of these properties under 'header' to the HTTP Headers of the subsequent GET or PUT request that it performs. That allows the Basic HTTP authentication used to authorize the Batch API request to also authorize the upload/download action. There's likely further work to do here. There's an 'authenticated' boolean key in the Batch API response that can be set, and there is an 'LFS-Authenticate' header that is used instead of 'WWW-Authenticate'[1]. (We likely need to support both, since some hosting solutions are likely to only respond with the latter.) In any event, this works with SCM Manager, so there is real world benefit. I'm limiting the headers returned to 'Basic', because that's all the lfs spec calls out. In practice, I've seen gitbucket emit custom header content[2]. [1] https://github.com/git-lfs/git-lfs/blob/master/docs/api/batch.md#response-errors [2] https://github.com/gitbucket/gitbucket/blob/35655f33c7713f08515ed640ece0948acd6d6168/src/main/scala/gitbucket/core/servlet/GitRepositoryServlet.scala#L119

/*
 * xdiff.cc - fuzzer harness for thirdparty/xdiff
 *
 * Copyright 2018, Google Inc.
 *
 * This software may be used and distributed according to the terms of
 * the GNU General Public License, incorporated herein by reference.
 */
#include "thirdparty/xdiff/xdiff.h"
#include <inttypes.h>
#include <stdlib.h>

extern "C" {

int hunk_consumer(long a1, long a2, long b1, long b2, void *priv)
{
	// TODO: probably also test returning -1 from this when things break?
	return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
{
	if (!Size) {
		return 0;
	}
	// figure out a random point in [0, Size] to split our input.
	size_t split = Data[0] / 255.0 * Size;

	mmfile_t a, b;

	// `a` input to diff is data[1:split]
	a.ptr = (char *)Data + 1;
	// which has len split-1
	a.size = split - 1;
	// `b` starts at the next byte after `a` ends
	b.ptr = a.ptr + a.size;
	b.size = Size - split;
	xpparam_t xpp = {
	    XDF_INDENT_HEURISTIC, /* flags */
	};
	xdemitconf_t xecfg = {
	    XDL_EMIT_BDIFFHUNK, /* flags */
	    hunk_consumer,      /* hunk_consume_func */
	};
	xdemitcb_t ecb = {
	    NULL, /* priv */
	};
	xdl_diff(&a, &b, &xpp, &xecfg, &ecb);
	return 0; // Non-zero return values are reserved for future use.
}

#ifdef HG_FUZZER_INCLUDE_MAIN
int main(int argc, char **argv)
{
	const char data[] = "asdf";
	return LLVMFuzzerTestOneInput((const uint8_t *)data, 4);
}
#endif

} // extern "C"