fuzz: bring oss-fuzz initial code converted to C89

# FIXME, probably adapt from file in ../unit

#***************************************************************************

#                                  _   _ ____  _

#  Project                     ___| | | |  _ \| |

#                             / __| | | | |_) | |

#                            | (__| |_| |  _ <| |___

#                             \___|\___/|_| \_\_____|

#

# Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.

#

# This software is licensed as described in the file COPYING, which

# you should have received as part of this distribution. The terms

# are also available at https://curl.haxx.se/docs/copyright.html.

#

# You may opt to use, copy, modify, merge, publish, distribute and/or sell

# copies of the Software, and permit persons to whom the Software is

# furnished to do so, under the terms of the COPYING file.

#

# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY

# KIND, either express or implied.

#

###########################################################################

# FIXME, probably adapt from file in ../unit

FUZZER_HTTP11 = curl_fuzzer.c

FUZZER_HTTP11_CPPFLAGS = $(AM_CPPFLAGS)

FUZZER_FTP = curl_fuzzer.c

FUZZER_FTP_CPPFLAGS = -DFUZZER_FTP $(AM_CPPFLAGS)

FUZZER_IMAP = curl_fuzzer.c

FUZZER_IMAP_CPPFLAGS = -DFUZZER_IMAP $(AM_CPPFLAGS)

FUZZER_POP3 = curl_fuzzer.c

FUZZER_POP3_CPPFLAGS = -DFUZZER_POP3 $(AM_CPPFLAGS)

FUZZER_HTTP_UPLOAD = curl_fuzzer.c

FUZZER_HTTP_UPLOAD_CPPFLAGS = -DFUZZER_HTTP_UPLOAD $(AM_CPPFLAGS)

FUZZER_HTTP2 = curl_fuzzer.c

FUZZER_HTTP2_CPPFLAGS = -DFUZZER_HTTP2 $(AM_CPPFLAGS)

Fuzz tests

==========

The goal is to add tests for *ALL* protocols supported in libcurl.

We will need some additional patches in the future, to increase coverage.

Building the fuzz target

========================

FIXME fill out once the makefiles are in order.

 No newline at end of file

/*

# Copyright 2016 Google Inc.

#

# 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 <errno.h>

#include <fcntl.h>

#include <netinet/in.h>

#include <stddef.h>

#include <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/select.h>

#include <sys/socket.h>

#include <sys/stat.h>

#include <sys/time.h>

#include <sys/types.h>

#include <unistd.h>

#include <curl/curl.h>

static const void *cur_data;

static int cur_size = -1;

static int server_fd = -1;

static int client_fd = -1;

static int wrote = 0;

static void fail(const char *why) {

  perror(why);

  exit(1);

}

static curl_socket_t open_sock(void *ctx, curlsocktype purpose,

                               struct curl_sockaddr *address) {

  if(cur_size == -1) {

    fail("not fuzzing");

  }

  if(server_fd != -1 || client_fd != -1) {

    fail("already connected");

  }

  int fds[2];

  if(socketpair(AF_UNIX, SOCK_STREAM, 0, fds)) {

    fail("socketpair");

  }

  server_fd = fds[0];

  client_fd = fds[1];

  if(write(server_fd, cur_data, cur_size) != cur_size) {

    fail("write");

  }

  if(shutdown(server_fd, SHUT_WR)) {

    fail("shutdown");

  }

  return client_fd;

}

static int set_opt(void *ctx, curl_socket_t curlfd, curlsocktype purpose) {

  return CURL_SOCKOPT_ALREADY_CONNECTED;

}

static size_t write_callback(char *ptr, size_t size, size_t n, void *ctx) {

  return size * n;

}

static size_t read_callback(char *buf, size_t size, size_t n, void *ctx) {

  if(wrote || size * n == 0) {

    return 0;

  }

  wrote = 1;

  buf[0] = 'a';

  return 1;

}

int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {

  cur_data = Data;

  cur_size = Size;

  wrote = 0;

  CURL *curl = curl_easy_init();

  curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_callback);

  curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);

  curl_easy_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, open_sock);

  curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, set_opt);

#if defined(FUZZER_FTP)

  curl_easy_setopt(curl, CURLOPT_URL, "ftp://user@localhost/file.txt");

#elif defined(FUZZER_IMAP)

  curl_easy_setopt(curl, CURLOPT_USERNAME, "user");

  curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");

  curl_easy_setopt(curl, CURLOPT_URL, "imap://localhost");

#elif defined(FUZZER_POP3)

  curl_easy_setopt(curl, CURLOPT_USERNAME, "user");

  curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");

  curl_easy_setopt(curl, CURLOPT_URL, "pop3://localhost");

#elif defined(FUZZER_HTTP_UPLOAD)

  curl_easy_setopt(curl, CURLOPT_URL, "http://localhost/");

  curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);

  curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

#elif defined(FUZZER_HTTP2)

  curl_easy_setopt(curl, CURLOPT_URL, "http://localhost/");

  /* use non-TLS HTTP/2 without HTTP/1.1 Upgrade: */

  curl_easy_setopt(curl, CURLOPT_HTTP_VERSION,

                   CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE);

#else

  curl_easy_setopt(curl, CURLOPT_URL, "http://localhost/");

  curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);

#endif

  curl_easy_perform(curl);

  curl_easy_cleanup(curl);

  close(server_fd);

  close(client_fd);

  server_fd = -1;

  client_fd = -1;

  cur_data = NULL;

  cur_size = -1;

  return 0;

}