| Index: third_party/afl/src/libtokencap/libtokencap.so.c
|
| diff --git a/third_party/afl/src/libtokencap/libtokencap.so.c b/third_party/afl/src/libtokencap/libtokencap.so.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..696c913daf5a7d6dd4c526a42dadc10fb5ecbcbd
|
| --- /dev/null
|
| +++ b/third_party/afl/src/libtokencap/libtokencap.so.c
|
| @@ -0,0 +1,253 @@
|
| +/*
|
| +
|
| + american fuzzy lop - extract tokens passed to strcmp / memcmp
|
| + -------------------------------------------------------------
|
| +
|
| + Written and maintained by Michal Zalewski <lcamtuf@google.com>
|
| +
|
| + Copyright 2016 Google Inc. All rights reserved.
|
| +
|
| + 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
|
| +
|
| + This Linux-only companion library allows you to instrument strcmp(),
|
| + memcmp(), and related functions to automatically extract tokens.
|
| + See README.tokencap for more info.
|
| +
|
| + */
|
| +
|
| +#include <stdio.h>
|
| +#include <string.h>
|
| +#include <ctype.h>
|
| +
|
| +#include "../types.h"
|
| +#include "../config.h"
|
| +
|
| +#ifndef __linux__
|
| +# error "Sorry, this library is Linux-specific for now!"
|
| +#endif /* !__linux__ */
|
| +
|
| +
|
| +/* Mapping data and such */
|
| +
|
| +#define MAX_MAPPINGS 1024
|
| +
|
| +static struct mapping {
|
| + void *st, *en;
|
| +} __tokencap_ro[MAX_MAPPINGS];
|
| +
|
| +static u32 __tokencap_ro_cnt;
|
| +static u8 __tokencap_ro_loaded;
|
| +static FILE* __tokencap_out_file;
|
| +
|
| +
|
| +/* Identify read-only regions in memory. Only parameters that fall into these
|
| + ranges are worth dumping when passed to strcmp() and so on. Read-write
|
| + regions are far more likely to contain user input instead. */
|
| +
|
| +static void __tokencap_load_mappings(void) {
|
| +
|
| + u8 buf[MAX_LINE];
|
| + FILE* f = fopen("/proc/self/maps", "r");
|
| +
|
| + __tokencap_ro_loaded = 1;
|
| +
|
| + if (!f) return;
|
| +
|
| + while (fgets(buf, MAX_LINE, f)) {
|
| +
|
| + u8 rf, wf;
|
| + void* st, *en;
|
| +
|
| + if (sscanf(buf, "%p-%p %c%c", &st, &en, &rf, &wf) != 4) continue;
|
| + if (wf == 'w' || rf != 'r') continue;
|
| +
|
| + __tokencap_ro[__tokencap_ro_cnt].st = (void*)st;
|
| + __tokencap_ro[__tokencap_ro_cnt].en = (void*)en;
|
| +
|
| + if (++__tokencap_ro_cnt == MAX_MAPPINGS) break;
|
| +
|
| + }
|
| +
|
| + fclose(f);
|
| +
|
| +}
|
| +
|
| +
|
| +/* Check an address against the list of read-only mappings. */
|
| +
|
| +static u8 __tokencap_is_ro(const void* ptr) {
|
| +
|
| + u32 i;
|
| +
|
| + if (!__tokencap_ro_loaded) __tokencap_load_mappings();
|
| +
|
| + for (i = 0; i < __tokencap_ro_cnt; i++)
|
| + if (ptr >= __tokencap_ro[i].st && ptr <= __tokencap_ro[i].en) return 1;
|
| +
|
| + return 0;
|
| +
|
| +}
|
| +
|
| +
|
| +/* Dump an interesting token to output file, quoting and escaping it
|
| + properly. */
|
| +
|
| +static void __tokencap_dump(const u8* ptr, size_t len, u8 is_text) {
|
| +
|
| + u8 buf[MAX_AUTO_EXTRA * 4 + 1];
|
| + u32 i;
|
| + u32 pos = 0;
|
| +
|
| + if (len < MIN_AUTO_EXTRA || len > MAX_AUTO_EXTRA) return;
|
| +
|
| + for (i = 0; i < len; i++) {
|
| +
|
| + if (is_text && !ptr[i]) break;
|
| +
|
| + switch (ptr[i]) {
|
| +
|
| + case 0 ... 31:
|
| + case 127 ... 255:
|
| + case '\"':
|
| + case '\\':
|
| +
|
| + sprintf(buf + pos, "\\x%02x", ptr[i]);
|
| + pos += 4;
|
| + break;
|
| +
|
| + default:
|
| +
|
| + buf[pos++] = ptr[i];
|
| +
|
| + }
|
| +
|
| + }
|
| +
|
| + buf[pos] = 0;
|
| +
|
| + fprintf(__tokencap_out_file, "\"%s\"\n", buf);
|
| +
|
| +}
|
| +
|
| +
|
| +/* Replacements for strcmp(), memcmp(), and so on. Note that these will be used
|
| + only if the target is compiled with -fno-builtins and linked dynamically. */
|
| +
|
| +#undef strcmp
|
| +
|
| +int strcmp(const char* str1, const char* str2) {
|
| +
|
| + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, strlen(str1), 1);
|
| + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, strlen(str2), 1);
|
| +
|
| + while (1) {
|
| +
|
| + unsigned char c1 = *str1, c2 = *str2;
|
| +
|
| + if (c1 != c2) return (c1 > c2) ? 1 : -1;
|
| + if (!c1) return 0;
|
| + str1++; str2++;
|
| +
|
| + }
|
| +
|
| +}
|
| +
|
| +
|
| +#undef strncmp
|
| +
|
| +int strncmp(const char* str1, const char* str2, size_t len) {
|
| +
|
| + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, len, 1);
|
| + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, len, 1);
|
| +
|
| + while (len--) {
|
| +
|
| + unsigned char c1 = *str1, c2 = *str2;
|
| +
|
| + if (!c1) return 0;
|
| + if (c1 != c2) return (c1 > c2) ? 1 : -1;
|
| + str1++; str2++;
|
| +
|
| + }
|
| +
|
| + return 0;
|
| +
|
| +}
|
| +
|
| +
|
| +#undef strcasecmp
|
| +
|
| +int strcasecmp(const char* str1, const char* str2) {
|
| +
|
| + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, strlen(str1), 1);
|
| + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, strlen(str2), 1);
|
| +
|
| + while (1) {
|
| +
|
| + unsigned char c1 = tolower(*str1), c2 = tolower(*str2);
|
| +
|
| + if (c1 != c2) return (c1 > c2) ? 1 : -1;
|
| + if (!c1) return 0;
|
| + str1++; str2++;
|
| +
|
| + }
|
| +
|
| +}
|
| +
|
| +
|
| +#undef strncasecmp
|
| +
|
| +int strncasecmp(const char* str1, const char* str2, size_t len) {
|
| +
|
| + if (__tokencap_is_ro(str1)) __tokencap_dump(str1, len, 1);
|
| + if (__tokencap_is_ro(str2)) __tokencap_dump(str2, len, 1);
|
| +
|
| + while (len--) {
|
| +
|
| + unsigned char c1 = tolower(*str1), c2 = tolower(*str2);
|
| +
|
| + if (!c1) return 0;
|
| + if (c1 != c2) return (c1 > c2) ? 1 : -1;
|
| + str1++; str2++;
|
| +
|
| + }
|
| +
|
| + return 0;
|
| +
|
| +}
|
| +
|
| +
|
| +#undef memcmp
|
| +
|
| +int memcmp(const void* mem1, const void* mem2, size_t len) {
|
| +
|
| + if (__tokencap_is_ro(mem1)) __tokencap_dump(mem1, len, 0);
|
| + if (__tokencap_is_ro(mem2)) __tokencap_dump(mem2, len, 0);
|
| +
|
| + while (len--) {
|
| +
|
| + unsigned char c1 = *(const char*)mem1, c2 = *(const char*)mem2;
|
| + if (c1 != c2) return (c1 > c2) ? 1 : -1;
|
| + mem1++; mem2++;
|
| +
|
| + }
|
| +
|
| + return 0;
|
| +
|
| +}
|
| +
|
| +
|
| +/* Init code to open the output file (or default to stderr). */
|
| +
|
| +__attribute__((constructor)) void __tokencap_init(void) {
|
| +
|
| + u8* fn = getenv("AFL_TOKEN_FILE");
|
| + if (fn) __tokencap_out_file = fopen(fn, "a");
|
| + if (!__tokencap_out_file) __tokencap_out_file = stderr;
|
| +
|
| +}
|
| +
|
|
|