/* $NetBSD: dns_message_parse.c,v 1.2.4.2 2024/02/29 12:33:43 martin Exp $ */ /* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "fuzz.h" bool debug = false; static isc_mem_t *mctx = NULL; static uint8_t *output = NULL; static size_t output_len = 1024; static uint8_t render_buf[64 * 1024 - 1]; int LLVMFuzzerInitialize(int *argc __attribute__((unused)), char ***argv __attribute__((unused))) { isc_mem_create(&mctx); output = isc_mem_get(mctx, output_len); return (0); } static isc_result_t parse_message(isc_buffer_t *input, dns_message_t **messagep) { isc_result_t result; dns_message_t *message = NULL; dns_message_create(mctx, DNS_MESSAGE_INTENTPARSE, &message); result = dns_message_parse(message, input, DNS_MESSAGEPARSE_BESTEFFORT); if (result == DNS_R_RECOVERABLE) { result = ISC_R_SUCCESS; } if (result == ISC_R_SUCCESS && messagep != NULL) { *messagep = message; } else { dns_message_detach(&message); } return (result); } static isc_result_t print_message(dns_message_t *message) { isc_result_t result; isc_buffer_t buffer; do { isc_buffer_init(&buffer, output, output_len); result = dns_message_totext(message, &dns_master_style_debug, 0, &buffer); if (result == ISC_R_NOSPACE) { isc_mem_put(mctx, output, output_len); output_len *= 2; output = isc_mem_get(mctx, output_len); continue; } } while (result == ISC_R_NOSPACE); if (debug) { fprintf(stderr, "%.*s\n", (int)isc_buffer_usedlength(&buffer), output); } return (result); } #define CHECKRESULT(r, f) \ { \ r = (f); \ if (r != ISC_R_SUCCESS) { \ goto cleanup; \ } \ } static isc_result_t render_message(dns_message_t **messagep) { isc_result_t result; dns_message_t *message = *messagep; isc_buffer_t buffer; dns_compress_t cctx; isc_buffer_init(&buffer, render_buf, sizeof(render_buf)); message->from_to_wire = DNS_MESSAGE_INTENTRENDER; for (size_t i = 0; i < DNS_SECTION_MAX; i++) { message->counts[i] = 0; } result = dns_compress_init(&cctx, -1, mctx); if (result != ISC_R_SUCCESS) { return (result); } CHECKRESULT(result, dns_message_renderbegin(message, &cctx, &buffer)); CHECKRESULT(result, dns_message_rendersection(message, DNS_SECTION_QUESTION, 0)); CHECKRESULT(result, dns_message_rendersection(message, DNS_SECTION_ANSWER, 0)); CHECKRESULT(result, dns_message_rendersection( message, DNS_SECTION_AUTHORITY, 0)); CHECKRESULT(result, dns_message_rendersection( message, DNS_SECTION_ADDITIONAL, 0)); dns_message_renderend(message); dns_compress_invalidate(&cctx); message->from_to_wire = DNS_MESSAGE_INTENTPARSE; dns_message_detach(messagep); result = parse_message(&buffer, messagep); return (result); cleanup: dns_compress_invalidate(&cctx); return (result); } int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { isc_buffer_t buffer; isc_result_t result; dns_message_t *message = NULL; if (size > 65535) { return (0); } isc_buffer_constinit(&buffer, data, size); isc_buffer_add(&buffer, size); isc_buffer_setactive(&buffer, size); result = parse_message(&buffer, &message); if (result != ISC_R_SUCCESS) { goto cleanup; } result = print_message(message); if (result != ISC_R_SUCCESS) { goto cleanup; } result = render_message(&message); if (result != ISC_R_SUCCESS) { goto cleanup; } result = print_message(message); if (result != ISC_R_SUCCESS) { goto cleanup; } cleanup: if (message != NULL) { dns_message_detach(&message); } return (0); }