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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:37:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:37:14 +0000 |
commit | ea648e70a989cca190cd7403fe892fd2dcc290b4 (patch) | |
tree | e2b6b1c647da68b0d4d66082835e256eb30970e8 /bin/named/fuzz.c | |
parent | Initial commit. (diff) | |
download | bind9-upstream/1%9.11.5.P4+dfsg.tar.xz bind9-upstream/1%9.11.5.P4+dfsg.zip |
Adding upstream version 1:9.11.5.P4+dfsg.upstream/1%9.11.5.P4+dfsgupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | bin/named/fuzz.c | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/bin/named/fuzz.c b/bin/named/fuzz.c new file mode 100644 index 0000000..92f3f8b --- /dev/null +++ b/bin/named/fuzz.c @@ -0,0 +1,483 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * 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 http://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +#include "config.h" + +#include <inttypes.h> +#include <stdbool.h> + +#include <named/fuzz.h> + +#ifdef ENABLE_AFL +#include <named/globals.h> +#include <named/server.h> +#include <sys/errno.h> + +#include <isc/app.h> +#include <isc/condition.h> +#include <isc/mutex.h> +#include <isc/thread.h> +#include <isc/util.h> +#include <named/log.h> +#include <dns/log.h> + +#include <stdlib.h> +#include <string.h> +#include <signal.h> +#include <arpa/inet.h> +#include <unistd.h> +#include <pthread.h> + +#ifndef __AFL_LOOP +#error To use American Fuzzy Lop you have to set CC to afl-clang-fast!!! +#endif + +/* + * We are using pthreads directly because we might be using it with unthreaded + * version of BIND, where all thread functions are mocks. Since AFL for now only + * works on Linux it's not a problem. + */ +static pthread_cond_t cond; +static pthread_mutex_t mutex; +static bool ready; + + +static void * +fuzz_main_client(void *arg) { + char *host; + char *port; + struct sockaddr_in servaddr; + int sockfd; + int loop; + void *buf; + + UNUSED(arg); + + /* + * Parse named -A argument in the "address:port" syntax. Due to + * the syntax used, this only supports IPv4 addresses. + */ + + host = strdup(ns_g_fuzz_named_addr); + RUNTIME_CHECK(host != NULL); + port = strchr(host, ':'); + RUNTIME_CHECK(port != NULL); + *port = 0; + ++port; + + memset(&servaddr, 0, sizeof (servaddr)); + servaddr.sin_family = AF_INET; + RUNTIME_CHECK(inet_pton(AF_INET, host, &servaddr.sin_addr) == 1); + servaddr.sin_port = htons(atoi(port)); + + free(host); + + /* Wait for named to start. */ + while (!ns_g_run_done) { + usleep(10000); + } + + sockfd = socket(AF_INET, SOCK_DGRAM, 0); + RUNTIME_CHECK(sockfd != -1); + + buf = malloc(65536); + RUNTIME_CHECK(buf != NULL); + + loop = 100000; + while (loop--) { + ssize_t length; + + length = read(0, buf, 65536); + if (length <= 0) { + usleep(1000000); + continue; + } + + if (length > 4096) { + if (getenv("AFL_CMIN")) { + ns_server_flushonshutdown(ns_g_server, + false); + isc_app_shutdown(); + return (NULL); + } + raise(SIGSTOP); + continue; + } + + RUNTIME_CHECK(pthread_mutex_lock(&mutex) == ISC_R_SUCCESS); + + ready = false; + + ssize_t sent; + + sent = sendto(sockfd, buf, length, 0, + (struct sockaddr *) &servaddr, sizeof(servaddr)); + RUNTIME_CHECK(sent == length); + + /* unclog */ + recvfrom(sockfd, buf, 65536, MSG_DONTWAIT, NULL, NULL); + + while (!ready) + pthread_cond_wait(&cond, &mutex); + + RUNTIME_CHECK(pthread_mutex_unlock(&mutex) == ISC_R_SUCCESS); + } + + free(buf); + close(sockfd); + + ns_server_flushonshutdown(ns_g_server, false); + isc_app_shutdown(); + + return (NULL); +} + +static void * +fuzz_main_resolver(void *arg) { + char *shost, *sport, *rhost, *rport; + /* Query for A? aaaaaaaaaa.example. */ + char respacket[] = + "\0\0\1 \0\1\0\0\0\0\0\0\naaaaaaaaaa\7example\0\0\1\0\1"; + struct sockaddr_in servaddr, recaddr, recvaddr; + int sockfd; + int listenfd; + int loop; + char *buf, *rbuf; + + UNUSED(arg); + + /* + * Parse named -A argument in the "laddress:sport:raddress:rport" + * syntax. Due to the syntax used, this only supports IPv4 addresses. + */ + + shost = strdup(ns_g_fuzz_named_addr); + RUNTIME_CHECK(shost != NULL); + sport = strchr(shost, ':'); + RUNTIME_CHECK(sport != NULL); + *sport = 0; + sport++; + rhost = strchr(sport, ':'); + RUNTIME_CHECK(rhost != NULL); + *rhost = 0; + rhost++; + rport = strchr(rhost, ':'); + RUNTIME_CHECK(rport != NULL); + *rport = 0; + rport++; + + memset(&servaddr, 0, sizeof (servaddr)); + servaddr.sin_family = AF_INET; + RUNTIME_CHECK(inet_pton(AF_INET, shost, &servaddr.sin_addr) == 1); + servaddr.sin_port = htons(atoi(sport)); + + memset(&recaddr, 0, sizeof (recaddr)); + recaddr.sin_family = AF_INET; + RUNTIME_CHECK(inet_pton(AF_INET, rhost, &recaddr.sin_addr) == 1); + recaddr.sin_port = htons(atoi(rport)); + + free(shost); + + /* Wait for named to start */ + while (!ns_g_run_done) { + usleep(10000); + } + + sockfd = socket(AF_INET, SOCK_DGRAM, 0); + RUNTIME_CHECK(sockfd != -1); + + listenfd = socket(AF_INET, SOCK_DGRAM, 0); + RUNTIME_CHECK(listenfd != -1); + RUNTIME_CHECK(bind(listenfd, (struct sockaddr *)&recaddr, + sizeof(struct sockaddr_in)) == 0); + + buf = malloc(65536); + rbuf = malloc(65536); + RUNTIME_CHECK(buf != NULL); + RUNTIME_CHECK(rbuf != NULL); + + loop = 100000; + while (loop--) { + ssize_t length; + memset(buf, 0, 16); + length = read(0, buf, 65536); + if (length <= 0) { + usleep(1000000); + continue; + } + + if (length > 4096) { + if (getenv("AFL_CMIN")) { + ns_server_flushonshutdown(ns_g_server, + false); + isc_app_shutdown(); + return (NULL); + } + raise(SIGSTOP); + continue; + } + + if (length < 16) { + length = 16; + } + + RUNTIME_CHECK(pthread_mutex_lock(&mutex) == ISC_R_SUCCESS); + + ready = false; + + ssize_t sent; + /* Randomize query ID. */ + int id = random(); + respacket[0] = id >> 8; + respacket[1] = id & 0xff; + + /* flush */ + socklen_t socklen = sizeof(recvaddr); + sent = recvfrom(listenfd, rbuf, 65536, MSG_DONTWAIT, + (struct sockaddr *) &recvaddr, &socklen); + + sent = sendto(sockfd, respacket, sizeof(respacket), 0, + (struct sockaddr *) &servaddr, sizeof(servaddr)); + RUNTIME_CHECK(sent == sizeof(respacket)); + + socklen = sizeof(recvaddr); + sent = recvfrom(listenfd, rbuf, 65536, 0, + (struct sockaddr *) &recvaddr, &socklen); + RUNTIME_CHECK(sent > 0); + + /* Copy QID and set QR so that response is always processed. */ + buf[0] = rbuf[0]; + buf[1] = rbuf[1]; + buf[2] |= 0x80; + + sent = sendto(listenfd, buf, length, 0, + (struct sockaddr *) &recvaddr, sizeof(recvaddr)); + RUNTIME_CHECK(sent == length); + + /* We might get additional questions here (e.g. for CNAME). */ + for (;;) { + fd_set fds; + struct timeval tv; + int rv; + int max; + + FD_ZERO(&fds); + FD_SET(listenfd, &fds); + FD_SET(sockfd, &fds); + tv.tv_sec = 10; + tv.tv_usec = 0; + max = (listenfd > sockfd ? listenfd : sockfd)+1; + + rv = select(max, &fds, NULL, NULL, &tv); + RUNTIME_CHECK(rv > 0); + + if (FD_ISSET(sockfd, &fds)) { + /* It's the reply, we're done. */ + recvfrom(sockfd, buf, 65536, 0, NULL, NULL); + break; + } + + /* + * We've got additional question (eg. cname chain) + * We are bouncing it - setting QR flag and NOERROR + * rcode and sending it back. + */ + + length = recvfrom(listenfd, buf, 65536, 0, + (struct sockaddr *) &recvaddr, &socklen); + buf[2] |= 0x80; + buf[3] &= 0xF0; + sent = sendto(listenfd, buf, length, 0, + (struct sockaddr *) &recvaddr, + sizeof(recvaddr)); + RUNTIME_CHECK(sent == length); + } + + while (!ready) + pthread_cond_wait(&cond, &mutex); + + RUNTIME_CHECK(pthread_mutex_unlock(&mutex) == 0); + } + + free(buf); + free(rbuf); + close(sockfd); + ns_server_flushonshutdown(ns_g_server, false); + isc_app_shutdown(); + + /* + * It's here just for the signature, that's how AFL detects if it's + * a 'persistent mode' binary. + */ + __AFL_LOOP(0); + + return (NULL); +} + +static void * +fuzz_main_tcp(void *arg) { + char *host; + char *port; + struct sockaddr_in servaddr; + int sockfd; + char *buf; + int loop; + + UNUSED(arg); + + /* + * Parse named -A argument in the "address:port" syntax. Due to + * the syntax used, this only supports IPv4 addresses. + */ + + host = strdup(ns_g_fuzz_named_addr); + RUNTIME_CHECK(host != NULL); + port = strchr(host, ':'); + RUNTIME_CHECK(port != NULL); + *port = 0; + ++port; + + memset(&servaddr, 0, sizeof (servaddr)); + servaddr.sin_family = AF_INET; + RUNTIME_CHECK(inet_pton(AF_INET, host, &servaddr.sin_addr) == 1); + servaddr.sin_port = htons(atoi(port)); + + free(host); + + /* Wait for named to start */ + while (!ns_g_run_done) { + usleep(10000); + } + + buf = malloc(65539); + RUNTIME_CHECK(buf != NULL); + + loop = 100000; + while (loop--) { + ssize_t length; + + if (ns_g_fuzz_type == ns_fuzz_tcpclient) { + /* + * To fuzz TCP client we have to put length at + * the start of packet. + */ + length = read(0, buf+2, 65535); + buf[0] = length >> 8; + buf[1] = length & 0xff; + length += 2; + } else { + length = read(0, buf, 65535); + } + if (length <= 0) { + usleep(1000000); + continue; + } + if (ns_g_fuzz_type == ns_fuzz_http) { + /* + * This guarantees that the request will be processed. + */ + buf[length++]='\r'; + buf[length++]='\n'; + buf[length++]='\r'; + buf[length++]='\n'; + } + + RUNTIME_CHECK(pthread_mutex_lock(&mutex) == ISC_R_SUCCESS); + + ready = false; + + ssize_t sent; + int yes = 1; + int r; + sockfd = socket(AF_INET, SOCK_STREAM, 0); + + RUNTIME_CHECK(sockfd != -1); + RUNTIME_CHECK(setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, + &yes, sizeof(int)) == 0); + + do { + r = connect(sockfd, (struct sockaddr*)&servaddr, + sizeof(servaddr)); + } while (r != 0); + + sent = write(sockfd, buf, length); + RUNTIME_CHECK(sent == length); + close(sockfd); + + /* unclog */ + recvfrom(sockfd, buf, 65537, MSG_DONTWAIT, NULL, NULL); + + while (!ready) + pthread_cond_wait(&cond, &mutex); + + RUNTIME_CHECK(pthread_mutex_unlock(&mutex) == ISC_R_SUCCESS); + } + + free(buf); + close(sockfd); + ns_server_flushonshutdown(ns_g_server, false); + isc_app_shutdown(); + + return (NULL); +} + +#endif /* ENABLE_AFL */ + +void +named_fuzz_notify(void) { +#ifdef ENABLE_AFL + if (getenv("AFL_CMIN")) { + ns_server_flushonshutdown(ns_g_server, false); + isc_app_shutdown(); + return; + } + + raise(SIGSTOP); + + RUNTIME_CHECK(pthread_mutex_lock(&mutex) == 0); + + ready = true; + + RUNTIME_CHECK(pthread_cond_signal(&cond) == 0); + RUNTIME_CHECK(pthread_mutex_unlock(&mutex) == 0); +#endif /* ENABLE_AFL */ +} + +void +named_fuzz_setup(void) { +#ifdef ENABLE_AFL + if (getenv("__AFL_PERSISTENT") || getenv("AFL_CMIN")) { + pthread_t thread; + void *(fn) = NULL; + + switch (ns_g_fuzz_type) { + case ns_fuzz_client: + fn = fuzz_main_client; + break; + + case ns_fuzz_http: + case ns_fuzz_tcpclient: + case ns_fuzz_rndc: + fn = fuzz_main_tcp; + break; + case ns_fuzz_resolver: + fn = fuzz_main_resolver; + break; + default: + RUNTIME_CHECK(fn != NULL); + } + + RUNTIME_CHECK(pthread_mutex_init(&mutex, NULL) == 0); + RUNTIME_CHECK(pthread_cond_init(&cond, NULL) == 0); + RUNTIME_CHECK(pthread_create(&thread, NULL, fn, NULL) == 0); + } +#endif /* ENABLE_AFL */ +} |