/***************************************************************************

 *                                  _   _ ____  _

 *  Project                     ___| | | |  _ \| |

 *                             / __| | | | |_) | |

 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 2017, Max Dymond, <cmeister2@gmail.com>, 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.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.

 *

 ***************************************************************************/

#include <stdlib.h>

#include <string.h>

#include <curl/curl.h>

#include "curl_fuzzer.h"

/**

 * TLV access function - gets the first TLV from a data stream.

 */

int fuzz_get_first_tlv(FUZZ_DATA *fuzz,

                       TLV *tlv)

{

  /* Reset the cursor. */

  fuzz->state.data_pos = 0;

  return fuzz_get_tlv_comn(fuzz, tlv);

}

/**

 * TLV access function - gets the next TLV from a data stream.

*/

int fuzz_get_next_tlv(FUZZ_DATA *fuzz,

                      TLV *tlv)

{

  /* Advance the cursor by the full length of the previous TLV. */

  fuzz->state.data_pos += sizeof(TLV_RAW) + tlv->length;

  /* Work out if there's a TLV's worth of data to read */

  if(fuzz->state.data_pos + sizeof(TLV_RAW) > fuzz->state.data_len) {

    /* No more TLVs to parse */

    return TLV_RC_NO_MORE_TLVS;

  }

  return fuzz_get_tlv_comn(fuzz, tlv);

}

/**

 * Common TLV function for accessing TLVs in a data stream.

 */

int fuzz_get_tlv_comn(FUZZ_DATA *fuzz,

                      TLV *tlv)

{

  int rc = 0;

  size_t data_offset;

  TLV_RAW *raw;

  /* Start by casting the data stream to a TLV. */

  raw = (TLV_RAW *)&fuzz->state.data[fuzz->state.data_pos];

  data_offset = fuzz->state.data_pos + sizeof(TLV_RAW);

  /* Set the TLV values. */

  tlv->type = to_u16(raw->raw_type);

  tlv->length = to_u32(raw->raw_length);

  tlv->value = &fuzz->state.data[data_offset];

  FV_PRINTF(fuzz, "TLV: type %x length %u\n", tlv->type, tlv->length);

  /* Use uint64s to verify lengths of TLVs so that overflow problems don't

     matter. */

  uint64_t check_length = data_offset;

  check_length += tlv->length;

  uint64_t remaining_len = fuzz->state.data_len;

  FV_PRINTF(fuzz, "Check length of data: %" PRIu64 " \n", check_length);

  FV_PRINTF(fuzz, "Remaining length of data: %" PRIu64 " \n", remaining_len);

  /* Sanity check that the TLV length is ok. */

  if(check_length > remaining_len) {

    FV_PRINTF(fuzz, "Returning TLV_RC_SIZE_ERROR\n");

    rc = TLV_RC_SIZE_ERROR;

  }

  return rc;

}

/**

 * Do different actions on the CURL handle for different received TLVs.

 */

int fuzz_parse_tlv(FUZZ_DATA *fuzz, TLV *tlv)

{

  int rc;

  char *tmp = NULL;

  uint32_t tmp_u32;

  curl_slist *new_list;

  switch(tlv->type) {

    /* The pointers in response TLVs will always be valid as long as the fuzz

       data is in scope, which is the entirety of this file. */

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE0, 0);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE1, 1);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE2, 2);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE3, 3);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE4, 4);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE5, 5);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE6, 6);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE7, 7);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE8, 8);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE9, 9);

    FRESPONSETLV(&fuzz->sockman[0], TLV_TYPE_RESPONSE10, 10);

    FRESPONSETLV(&fuzz->sockman[1], TLV_TYPE_SECOND_RESPONSE0, 0);

    FRESPONSETLV(&fuzz->sockman[1], TLV_TYPE_SECOND_RESPONSE1, 1);

    case TLV_TYPE_UPLOAD1:

      /* The pointers in the TLV will always be valid as long as the fuzz data

         is in scope, which is the entirety of this file. */

      FCHECK_OPTION_UNSET(fuzz, CURLOPT_UPLOAD);

      fuzz->upload1_data = tlv->value;

      fuzz->upload1_data_len = tlv->length;

      FSET_OPTION(fuzz, CURLOPT_UPLOAD, 1L);

      FSET_OPTION(fuzz,

                  CURLOPT_INFILESIZE_LARGE,

                  (curl_off_t)fuzz->upload1_data_len);

      break;

    case TLV_TYPE_HEADER:

      /* Limit the number of headers that can be added to a message to prevent

         timeouts. */

      if(fuzz->header_list_count >= TLV_MAX_NUM_CURLOPT_HEADER) {

        rc = 255;

        goto EXIT_LABEL;

      }

      tmp = fuzz_tlv_to_string(tlv);

      if (tmp == NULL) {

        // keep on despite allocation failure

        break;

      }

      new_list = curl_slist_append(fuzz->header_list, tmp);

      if (new_list == NULL) {

        break;

      }

      fuzz->header_list = new_list;

      fuzz->header_list_count++;

      break;

    case TLV_TYPE_MAIL_RECIPIENT:

      /* Limit the number of headers that can be added to a message to prevent

         timeouts. */

      if(fuzz->header_list_count >= TLV_MAX_NUM_CURLOPT_HEADER) {

        rc = 255;

        goto EXIT_LABEL;

      }

      tmp = fuzz_tlv_to_string(tlv);

      if (tmp == NULL) {

        // keep on despite allocation failure

        break;

      }

      new_list = curl_slist_append(fuzz->mail_recipients_list, tmp);

      if (new_list != NULL) {

        fuzz->mail_recipients_list = new_list;

        fuzz->header_list_count++;

      }

      break;

    case TLV_TYPE_MIME_PART:

      if(fuzz->mime == NULL) {

        fuzz->mime = curl_mime_init(fuzz->easy);

      }

      fuzz->part = curl_mime_addpart(fuzz->mime);

      /* This TLV may have sub TLVs. */

      fuzz_add_mime_part(tlv, fuzz->part);

      break;

    case TLV_TYPE_POSTFIELDS:

      FCHECK_OPTION_UNSET(fuzz, CURLOPT_POSTFIELDS);

      fuzz->postfields = fuzz_tlv_to_string(tlv);

      FSET_OPTION(fuzz, CURLOPT_POSTFIELDS, fuzz->postfields);

      break;

    case TLV_TYPE_HTTPPOSTBODY:

      FCHECK_OPTION_UNSET(fuzz, CURLOPT_HTTPPOST);

      fuzz_setup_http_post(fuzz, tlv);

      FSET_OPTION(fuzz, CURLOPT_HTTPPOST, fuzz->httppost);

      break;

    /* Define a set of u32 options. */

    FU32TLV(fuzz, TLV_TYPE_HTTPAUTH, CURLOPT_HTTPAUTH);

    FU32TLV(fuzz, TLV_TYPE_OPTHEADER, CURLOPT_HEADER);

    FU32TLV(fuzz, TLV_TYPE_NOBODY, CURLOPT_NOBODY);

    FU32TLV(fuzz, TLV_TYPE_FOLLOWLOCATION, CURLOPT_FOLLOWLOCATION);

    FU32TLV(fuzz, TLV_TYPE_WILDCARDMATCH, CURLOPT_WILDCARDMATCH);

    FU32TLV(fuzz, TLV_TYPE_RTSP_REQUEST, CURLOPT_RTSP_REQUEST);

    FU32TLV(fuzz, TLV_TYPE_RTSP_CLIENT_CSEQ, CURLOPT_RTSP_CLIENT_CSEQ);

    FU32TLV(fuzz, TLV_TYPE_HTTP_VERSION, CURLOPT_HTTP_VERSION);

    FU32TLV(fuzz, TLV_TYPE_NETRC, CURLOPT_NETRC);

    FU32TLV(fuzz, TLV_TYPE_WS_OPTIONS, CURLOPT_WS_OPTIONS);

    FU32TLV(fuzz, TLV_TYPE_CONNECT_ONLY, CURLOPT_CONNECT_ONLY);

    FU32TLV(fuzz, TLV_TYPE_POST, CURLOPT_POST);

    /* Define a set of singleton TLVs - they can only have their value set once

       and all follow the same pattern. */

    FSINGLETONTLV(fuzz, TLV_TYPE_URL, CURLOPT_URL);

    FSINGLETONTLV(fuzz, TLV_TYPE_DOH_URL, CURLOPT_DOH_URL);

    FSINGLETONTLV(fuzz, TLV_TYPE_USERNAME, CURLOPT_USERNAME);

    FSINGLETONTLV(fuzz, TLV_TYPE_PASSWORD, CURLOPT_PASSWORD);

    FSINGLETONTLV(fuzz, TLV_TYPE_COOKIE, CURLOPT_COOKIE);

    FSINGLETONTLV(fuzz, TLV_TYPE_RANGE, CURLOPT_RANGE);

    FSINGLETONTLV(fuzz, TLV_TYPE_CUSTOMREQUEST, CURLOPT_CUSTOMREQUEST);

    FSINGLETONTLV(fuzz, TLV_TYPE_MAIL_FROM, CURLOPT_MAIL_FROM);

    FSINGLETONTLV(fuzz, TLV_TYPE_ACCEPTENCODING, CURLOPT_ACCEPT_ENCODING);

    FSINGLETONTLV(fuzz, TLV_TYPE_RTSP_SESSION_ID, CURLOPT_RTSP_SESSION_ID);

    FSINGLETONTLV(fuzz, TLV_TYPE_RTSP_STREAM_URI, CURLOPT_RTSP_STREAM_URI);

    FSINGLETONTLV(fuzz, TLV_TYPE_RTSP_TRANSPORT, CURLOPT_RTSP_TRANSPORT);

    FSINGLETONTLV(fuzz, TLV_TYPE_MAIL_AUTH, CURLOPT_MAIL_AUTH);

    FSINGLETONTLV(fuzz, TLV_TYPE_LOGIN_OPTIONS, CURLOPT_LOGIN_OPTIONS);

    FSINGLETONTLV(fuzz, TLV_TYPE_XOAUTH2_BEARER, CURLOPT_XOAUTH2_BEARER);

    FSINGLETONTLV(fuzz, TLV_TYPE_USERPWD, CURLOPT_USERPWD);

    FSINGLETONTLV(fuzz, TLV_TYPE_USERAGENT, CURLOPT_USERAGENT);

    FSINGLETONTLV(fuzz, TLV_TYPE_SSH_HOST_PUBLIC_KEY_SHA256, CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256);

    default:

      /* The fuzzer generates lots of unknown TLVs - we don't want these in the

         corpus so we reject any unknown TLVs. */

      rc = 127;

      goto EXIT_LABEL;

      break;

  }

  rc = 0;

EXIT_LABEL:

  fuzz_free((void **)&tmp);

  return rc;

}

/**

 * Converts a TLV data and length into an allocated string.

 */

char *fuzz_tlv_to_string(TLV *tlv)

{

  char *tlvstr;

  /* Allocate enough space, plus a null terminator */

  tlvstr = (char *)malloc(tlv->length + 1);

  if(tlvstr != NULL) {

    memcpy(tlvstr, tlv->value, tlv->length);

    tlvstr[tlv->length] = 0;

  }

  return tlvstr;

}

/* set up for CURLOPT_HTTPPOST, an alternative API to CURLOPT_MIMEPOST */

void fuzz_setup_http_post(FUZZ_DATA *fuzz, TLV *tlv)

{

  if (fuzz->httppost == NULL) {

    struct curl_httppost *post = NULL;

    struct curl_httppost *last = NULL;

    fuzz->post_body = fuzz_tlv_to_string(tlv);

    if (fuzz->post_body == NULL) {

      return;

    }

    /* This is just one of several possible entrypoints to

     * the HTTPPOST API. see https://curl.se/libcurl/c/curl_formadd.html

     * for lots of others which could be added here.

     */

    curl_formadd(&post, &last,

     CURLFORM_COPYNAME, FUZZ_HTTPPOST_NAME,

     CURLFORM_PTRCONTENTS, fuzz->post_body,

     CURLFORM_CONTENTLEN, (curl_off_t) strlen(fuzz->post_body),

     CURLFORM_END);

    fuzz->last_post_part = last;

    fuzz->httppost = post;

  }

  return;

}

/**

 * Extract the values from the TLV.

 */

int fuzz_add_mime_part(TLV *src_tlv, curl_mimepart *part)

{

  FUZZ_DATA part_fuzz;

  TLV tlv;

  int rc = 0;

  int tlv_rc;

  memset(&part_fuzz, 0, sizeof(FUZZ_DATA));

  if(src_tlv->length < sizeof(TLV_RAW)) {

    /* Not enough data for a single TLV - don't continue */

    goto EXIT_LABEL;

  }

  /* Set up the state parser */

  part_fuzz.state.data = src_tlv->value;

  part_fuzz.state.data_len = src_tlv->length;

  for(tlv_rc = fuzz_get_first_tlv(&part_fuzz, &tlv);

      tlv_rc == 0;

      tlv_rc = fuzz_get_next_tlv(&part_fuzz, &tlv)) {

    /* Have the TLV in hand. Parse the TLV. */

    rc = fuzz_parse_mime_tlv(part, &tlv);

    if(rc != 0) {

      /* Failed to parse the TLV. Can't continue. */

      goto EXIT_LABEL;

    }

  }

  if(tlv_rc != TLV_RC_NO_MORE_TLVS) {

    /* A TLV call failed. Can't continue. */

    goto EXIT_LABEL;

  }

EXIT_LABEL:

  return(rc);

}

/**

 * Do different actions on the mime part for different received TLVs.

 */

int fuzz_parse_mime_tlv(curl_mimepart *part, TLV *tlv)

{

  int rc;

  char *tmp;

  switch(tlv->type) {

    case TLV_TYPE_MIME_PART_NAME:

      tmp = fuzz_tlv_to_string(tlv);

      curl_mime_name(part, tmp);

      fuzz_free((void **)&tmp);

      break;

    case TLV_TYPE_MIME_PART_DATA:

      curl_mime_data(part, (const char *)tlv->value, tlv->length);

      break;

    default:

      /* The fuzzer generates lots of unknown TLVs - we don't want these in the

         corpus so we reject any unknown TLVs. */

      rc = 255;

      goto EXIT_LABEL;

      break;

  }

  rc = 0;

EXIT_LABEL:

  return rc;

}