tests/fuzzing/fuzz_translate_generic.c

//
// liblouis Braille Translation and Back-Translation Library
//
// Copyright (C) 2022 Anna Stan, Nicolas Morel, Kalilou Mamadou Dramé
//
// This file is part of liblouis.
//
// liblouis is free software: you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published
// by the Free Software Foundation, either version 2.1 of the License, or
// (at your option) any later version.
//
// liblouis is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with liblouis. If not, see <http://www.gnu.org/licenses/>.
//

#include <config.h>

#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include <internal.h>
#include <liblouis.h>
#include <assert.h>
#include <unistd.h>

#define LANGUAGE	"en"

static int initialized = 0;

#define BOLDRED(x)	"\x1b[31m\x1b[1m" x "\x1b[0m"

static const char *table_default;

static void __attribute__((destructor))
free_ressources(void) {
	lou_free();
}

void
avoid_log(logLevels level, const char *msg) {
	(void) level;
	(void) msg;
}

extern int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);

int
LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
	int inputLen = 0;
	int outputLen = 0;
    static int counter = 0;
	if (!initialized)
	{
		lou_registerLogCallback(avoid_log);
		initialized = 1;
	}
    
    if (size < 512) {
        return 0;
    }

    // Write first half of fuzz data to a table file.
    char new_file[256];
    sprintf(new_file, "/tmp/libfuzzer-%d.ctb", counter);
    counter++;

	FILE *fp = fopen(new_file, "wb");
	if (!fp) {
		return 0;
    }
	fwrite(data, 512, 1, fp);
	fclose(fp);

    // Adjust data pointer to after the table file data.
    data += 512;
    size -= 512;

    /* check if this works, otherwise bail */
    if (lou_checkTable(new_file) == 0) {
        lou_free();
        unlink(new_file);
        return 0;
    }
	char *mutable_data = NULL;
    table_default = new_file;

	mutable_data = strndup((char*)data, size);
	if (!mutable_data) 
	{
		perror("malloc");
		exit(1);
	}

	widechar *inputText = malloc((size*16+1)*sizeof(widechar));
	int len = (int)_lou_extParseChars(mutable_data, inputText);
	free(mutable_data);
	if (len <= 0) {
		free(inputText);
        unlink(new_file);
        lou_free();
		return -1;
	}

	assert(len <= (size*16));
	inputLen = len;
	outputLen = len*16;
	widechar *outputText = malloc((outputLen+1)*sizeof(widechar));

	lou_translateString(table_default, inputText, &inputLen, outputText, &outputLen, NULL, NULL, ucBrl);

	free(inputText);
	free(outputText);
    lou_free();
    unlink(new_file);

	return 0;
}

extern int LLVMFuzzerRunDriver(int *argc, char ***argv,
                              int (*UserCb)(const uint8_t *Data, size_t Size));

int main(int argc, char *argv[]) {
       LLVMFuzzerRunDriver(&argc, &argv, LLVMFuzzerTestOneInput);
}