diff options
Diffstat (limited to 'custom_mutators')
| -rw-r--r-- | custom_mutators/README.md | 10 | ||||
| -rw-r--r-- | custom_mutators/autotokens/Makefile | 16 | ||||
| -rw-r--r-- | custom_mutators/autotokens/README | 24 | ||||
| -rw-r--r-- | custom_mutators/autotokens/TODO | 6 | ||||
| -rw-r--r-- | custom_mutators/autotokens/autotokens.cpp | 1143 | ||||
| -rw-r--r-- | custom_mutators/examples/custom_send.c | 9 | ||||
| -rw-r--r-- | custom_mutators/examples/example.c | 4 | ||||
| -rw-r--r-- | custom_mutators/examples/post_library_gif.so.c | 4 |
8 files changed, 1212 insertions, 4 deletions
diff --git a/custom_mutators/README.md b/custom_mutators/README.md index 0289e150..8d01856f 100644 --- a/custom_mutators/README.md +++ b/custom_mutators/README.md @@ -11,6 +11,16 @@ The `./examples` folder contains examples for custom mutators in python and C. In `./rust`, you will find rust bindings, including a simple example in `./rust/example` and an example for structured fuzzing, based on lain, in`./rust/example_lain`. +## The AFL++ grammar agnostic grammar mutator + +In `./autotokens` you find a token-level fuzzer that does not need to know +anything about the grammar of an input as long as it is in ascii and allows +whitespace. +It is very fast and effective. + +If you are looking for an example of how to effectively create a custom +mutator take a look at this one. + ## The AFL++ Grammar Mutator If you use git to clone AFL++, then the following will incorporate our diff --git a/custom_mutators/autotokens/Makefile b/custom_mutators/autotokens/Makefile new file mode 100644 index 00000000..ab1da4b6 --- /dev/null +++ b/custom_mutators/autotokens/Makefile @@ -0,0 +1,16 @@ +ifdef debug + CFLAGS += -fsanitize=address -Wall + CXX := clang++ +endif +ifdef DEBUG + CFLAGS += -fsanitize=address -Wall + CXX := clang++ +endif + +all: autotokens.so + +autotokens.so: autotokens.cpp + $(CXX) -g -O3 $(CFLAGS) -shared -fPIC -o autotokens.so -I../../include autotokens.cpp ../../src/afl-performance.o + +clean: + rm -f autotokens.so *~ core diff --git a/custom_mutators/autotokens/README b/custom_mutators/autotokens/README new file mode 100644 index 00000000..f82dcd98 --- /dev/null +++ b/custom_mutators/autotokens/README @@ -0,0 +1,24 @@ +# autotokens + +This implements an improved autotoken grammar fuzzing idea presented in +[Token-Level Fuzzing][https://www.usenix.org/system/files/sec21-salls.pdf]. +It is a grammar fuzzer without actually knowing the grammar. + +It is recommended to run with together in an instance with `CMPLOG`. + +If you have a dictionary (`-x`) this improves this custom grammar mutator. + +If **not** running with `CMPLOG`, it is possible to set +`AFL_CUSTOM_MUTATOR_ONLY` to concentrate on grammar bug classes. + +Do **not** set `AFL_DISABLE_TRIM` with this custom mutator! + +## Configuration via environment variables + +`AUTOTOKENS_ONLY_FAV` - only use this mutator on favorite queue items +`AUTOTOKENS_COMMENT` - what character or string starts a comment which will be + removed. Default: `/* ... */` +`AUTOTOKENS_ALTERNATIVE_TOKENIZE` - use an alternative tokenize implementation + (experimental) +`AUTOTOKENS_WHITESPACE` - whitespace string to use for ALTERNATIVE_TOKENIZE, + default is " " diff --git a/custom_mutators/autotokens/TODO b/custom_mutators/autotokens/TODO new file mode 100644 index 00000000..2e39511c --- /dev/null +++ b/custom_mutators/autotokens/TODO @@ -0,0 +1,6 @@ +cmplog: only add tokens that were found to fit? + +create from thin air if no good seed after a cycle and dict large enough? +(static u32 no_of_struct_inputs;) + +splicing -> check if whitespace/token is needed diff --git a/custom_mutators/autotokens/autotokens.cpp b/custom_mutators/autotokens/autotokens.cpp new file mode 100644 index 00000000..f9b5bd2e --- /dev/null +++ b/custom_mutators/autotokens/autotokens.cpp @@ -0,0 +1,1143 @@ +extern "C" { + +#include "afl-fuzz.h" + +} + +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> + +#include <iostream> +#include <fstream> +#include <unordered_map> +#include <vector> +#include <regex> + +#define AUTOTOKENS_DEBUG 0 +#define AUTOTOKENS_ONLY_FAV 0 +#define AUTOTOKENS_ALTERNATIVE_TOKENIZE 0 +#define AUTOTOKENS_CHANGE_MIN 8 +#define AUTOTOKENS_WHITESPACE " " +#define AUTOTOKENS_SIZE_MIN 8 +#define AUTOTOKENS_SPLICE_MIN 4 +#define AUTOTOKENS_SPLICE_MAX 64 +#ifndef AUTOTOKENS_SPLICE_DISABLE + #define AUTOTOKENS_SPLICE_DISABLE 0 +#endif + +#if AUTOTOKENS_SPLICE_MIN >= AUTOTOKENS_SIZE_MIN + #error SPLICE_MIN must be lower than SIZE_MIN +#endif + +using namespace std; + +typedef struct my_mutator { + + afl_state *afl; + +} my_mutator_t; + +#undef DEBUGF +#define DEBUGF \ + if (unlikely(debug)) fprintf +#define IFDEBUG if (unlikely(debug)) + +static afl_state *afl_ptr; +static int debug = AUTOTOKENS_DEBUG; +static int only_fav = AUTOTOKENS_ONLY_FAV; +static int alternative_tokenize = AUTOTOKENS_ALTERNATIVE_TOKENIZE; +static u32 current_id; +static u32 valid_structures; +static u32 whitespace_ids; +static u32 extras_cnt, a_extras_cnt; +static u64 all_spaces, all_tabs, all_lf, all_ws; +static u64 all_structure_items; +static u64 fuzz_count; +static unordered_map<string, vector<u32> *> file_mapping; +static unordered_map<u32, vector<u32> *> id_mapping; +static unordered_map<string, u32> token_to_id; +static unordered_map<u32, string> id_to_token; +static string whitespace = AUTOTOKENS_WHITESPACE; +static string output; +static regex *regex_comment_custom; +static regex regex_comment_star("/\\*([:print:]|\n)*?\\*/", + regex::multiline | regex::optimize); +static regex regex_word("[A-Za-z0-9_$.-]+", regex::optimize); +static regex regex_whitespace(R"([ \t]+)", regex::optimize); +static vector<u32> *s; // the structure of the currently selected input + +u32 good_whitespace_or_singleval() { + + u32 i = rand_below(afl_ptr, current_id); + if (id_to_token[i].size() == 1) { return i; } + i = rand_below(afl_ptr, all_ws); + if (i < all_spaces) { + + return 0; + + } else if (i < all_tabs) { + + return 1; + + } else + + return 2; // linefeed + +} + +extern "C" size_t afl_custom_fuzz(my_mutator_t *data, u8 *buf, size_t buf_size, + u8 **out_buf, u8 *add_buf, + size_t add_buf_size, size_t max_size) { + + (void)(data); + + if (s == NULL) { + + *out_buf = NULL; + return 0; + + } + + vector<u32> m = *s; // copy of the structure we will modify + u32 i, m_size = (u32)m.size(); + + u32 rounds = + MAX(AUTOTOKENS_CHANGE_MIN, + MIN(m_size >> 3, HAVOC_CYCLES * afl_ptr->queue_cur->perf_score * + afl_ptr->havoc_div / 256)); + // DEBUGF(stderr, "structure size: %lu, rounds: %u \n", m.size(), rounds); + +#if AUTOTOKENS_SPLICE_DISABLE == 1 + #define AUTOTOKENS_MUT_MAX 18 +#else + #define AUTOTOKENS_MUT_MAX 27 +#endif + + u32 max_rand = AUTOTOKENS_MUT_MAX, new_item, pos; + + for (i = 0; i < rounds; ++i) { + + switch (rand_below(afl_ptr, max_rand)) { + + /* CHANGE/MUTATE single item */ + case 0 ... 9: { + + pos = rand_below(afl_ptr, m_size); + u32 cur_item = m[pos]; + do { + + new_item = rand_below(afl_ptr, current_id); + + } while (unlikely( + + new_item == cur_item || + (!alternative_tokenize && + ((whitespace_ids < new_item && whitespace_ids >= cur_item) || + (whitespace_ids >= new_item && whitespace_ids < cur_item))))); + + DEBUGF(stderr, "MUT: %u -> %u\n", cur_item, new_item); + m[pos] = new_item; + break; + + } + + /* INSERT (m_size +1 so we insert also after last place) */ + case 10 ... 13: { + + do { + + new_item = rand_below(afl_ptr, current_id); + + } while (unlikely(!alternative_tokenize && new_item >= whitespace_ids)); + + u32 pos = rand_below(afl_ptr, m_size + 1); + m.insert(m.begin() + pos, new_item); + ++m_size; + DEBUGF(stderr, "INS: %u at %u\n", new_item, pos); + + if (likely(!alternative_tokenize)) { + + // if we insert an identifier or string we might need whitespace + if (id_to_token[new_item].size() > 1) { + + // need to insert before? + + if (pos && m[pos - 1] >= whitespace_ids && + id_to_token[m[pos - 1]].size() > 1) { + + m.insert(m.begin() + pos, good_whitespace_or_singleval()); + ++m_size; + + } + + if (pos + 1 < m_size && m[pos + 1] >= whitespace_ids && + id_to_token[m[pos + 1]].size() > 1) { + + // need to insert after? + + m.insert(m.begin() + pos + 1, good_whitespace_or_singleval()); + ++m_size; + + } + + } + + } + + break; + + } + +#if AUTOTOKENS_SPLICE_DISABLE != 1 + /* SPLICING */ + case 14 ... 22: { + + u32 strategy = rand_below(afl_ptr, 4), dst_off, n; + auto src = id_mapping[rand_below(afl_ptr, valid_structures)]; + u32 src_size = src->size(); + u32 src_off = rand_below(afl_ptr, src_size - AUTOTOKENS_SPLICE_MIN); + u32 rand_r = 1 + MAX(AUTOTOKENS_SPLICE_MIN, + MIN(AUTOTOKENS_SPLICE_MAX, src_size - src_off)); + + switch (strategy) { + + // insert + case 0: { + + dst_off = rand_below(afl_ptr, m_size); + n = AUTOTOKENS_SPLICE_MIN + + rand_below(afl_ptr, MIN(AUTOTOKENS_SPLICE_MAX, + rand_r - AUTOTOKENS_SPLICE_MIN)); + m.insert(m.begin() + dst_off, src->begin() + src_off, + src->begin() + src_off + n); + m_size += n; + DEBUGF(stderr, "SPLICE-INS: %u at %u\n", n, dst_off); + + break; + + } + + // overwrite + default: { + + dst_off = rand_below(afl_ptr, m_size - AUTOTOKENS_SPLICE_MIN); + n = AUTOTOKENS_SPLICE_MIN + + rand_below( + afl_ptr, + MIN(AUTOTOKENS_SPLICE_MAX - AUTOTOKENS_SPLICE_MIN, + MIN(m_size - dst_off - AUTOTOKENS_SPLICE_MIN, + src_size - src_off - AUTOTOKENS_SPLICE_MIN))); + + copy(src->begin() + src_off, src->begin() + src_off + n, + m.begin() + dst_off); + + DEBUGF(stderr, "SPLICE-MUT: %u at %u\n", n, dst_off); + break; + + } + + } + + if (likely(!alternative_tokenize)) { + + // do we need a whitespace/token at the beginning? + if (dst_off && id_to_token[m[dst_off - 1]].size() > 1 && + id_to_token[m[dst_off]].size() > 1) { + + m.insert(m.begin() + dst_off, good_whitespace_or_singleval()); + ++m_size; + + } + + // do we need a whitespace/token at the end? + if (dst_off + n < m_size && + id_to_token[m[dst_off + n - 1]].size() > 1 && + id_to_token[m[dst_off + n]].size() > 1) { + + m.insert(m.begin() + dst_off + n, good_whitespace_or_singleval()); + ++m_size; + + } + + } + + break; + + } + +#endif + + /* ERASE - only if large enough */ + default: { + + if (m_size > 8) { + + do { + + pos = rand_below(afl_ptr, m_size); + + } while (unlikely(m[pos] < whitespace_ids)); + + // if what we delete will result in a missing whitespace/token, + // instead of deleting we switch the item to a whitespace or token. + if (likely(!alternative_tokenize) && pos && pos + 1 < m_size && + id_to_token[m[pos - 1]].size() > 1 && + id_to_token[m[pos + 1]].size() > 1) { + + m[pos] = good_whitespace_or_singleval(); + + } else { + + m.erase(m.begin() + pos); + --m_size; + + } + + } else { + + // if the data is already too small do not try to make it smaller + // again this run. + + max_rand -= 4; + + } + + break; + + } + + } + + } + + u32 m_size_1 = m_size - 1; + output = ""; + + for (i = 0; i < m_size; ++i) { + + output += id_to_token[m[i]]; + if (unlikely(alternative_tokenize && i < m_size_1)) { + + output += whitespace; + + } + + } + + u32 mutated_size = (u32)output.size(); + u8 *mutated_out = (u8 *)output.data(); + + if (unlikely(mutated_size > max_size)) { mutated_size = max_size; } + + IFDEBUG { + + DEBUGF(stderr, "MUTATED to %u bytes:\n", mutated_size); + fwrite(output.data(), 1, mutated_size, stderr); + DEBUGF(stderr, "\n---\n"); + + } + + *out_buf = mutated_out; + ++fuzz_count; + return mutated_size; + +} + +/* I get f*cking stack overflow using C++ regex with a regex of + "\"[[:print:]]*?\"" if this matches a long string even with regex::optimize + enabled :-( */ +u8 my_search_string(string::const_iterator cur, string::const_iterator ende, + string::const_iterator *match_begin, + string::const_iterator *match_end) { + + string::const_iterator start = cur, found_begin; + u8 quote_type = 0; + + while (cur < ende) { + + switch (*cur) { + + case '"': { + + if (cur == start || *(cur - 1) != '\\') { + + if (!quote_type) { + + found_begin = cur; + quote_type = 1; + + } else if (quote_type == 1) { + + *match_begin = found_begin; + *match_end = cur + 1; + return 1; + + } + + } + + break; + + } + + case '\'': { + + if (cur == start || *(cur - 1) != '\\') { + + if (!quote_type) { + + found_begin = cur; + quote_type = 2; + + } else if (quote_type == 2) { + + *match_begin = found_begin; + *match_end = cur + 1; + return 1; + + } + + } + + break; + + } + + case '\n': + case '\r': + case 0: { + + quote_type = 0; + break; + + } + + default: + if (unlikely(quote_type && !isprint(*cur))) { quote_type = 0; } + break; + + } + + ++cur; + + } + + return 0; + +} + +/* We are not using afl_custom_queue_new_entry() because not every corpus entry + will be necessarily fuzzed. so we use afl_custom_queue_get() instead */ + +extern "C" unsigned char afl_custom_queue_get(void *data, + const unsigned char *filename) { + + (void)(data); + + if (likely(!debug)) { + + if (unlikely(!afl_ptr->custom_only) && + ((afl_ptr->shm.cmplog_mode && !afl_ptr->queue_cur->is_ascii) || + (only_fav && !afl_ptr->queue_cur->favored))) { + + s = NULL; + DEBUGF(stderr, "cmplog not ascii or only_fav and not favorite\n"); + return 0; + + } + + } + + // check if there are new dictionary entries and add them to the tokens + if (valid_structures) { + + while (extras_cnt < afl_ptr->extras_cnt) { + + u32 ok = 1, l = afl_ptr->extras[extras_cnt].len; + u8 *ptr = afl_ptr->extras[extras_cnt].data; + + for (u32 i = 0; i < l; ++i) { + + if (!isascii((int)ptr[i]) && !isprint((int)ptr[i])) { + + ok = 0; + break; + + } + + } + + if (ok) { + + token_to_id[(char *)ptr] = current_id; + id_to_token[current_id] = (char *)ptr; + ++current_id; + + } + + ++extras_cnt; + DEBUGF(stderr, "Added from dictionary: \"%s\"\n", ptr); + + } + + while (a_extras_cnt < afl_ptr->a_extras_cnt) { + + u32 ok = 1, l = afl_ptr->a_extras[a_extras_cnt].len; + u8 *ptr = afl_ptr->a_extras[a_extras_cnt].data; + + for (u32 i = 0; i < l; ++i) { + + if (!isascii((int)ptr[i]) && !isprint((int)ptr[i])) { + + ok = 0; + break; + + } + + } + + if (ok) { + + token_to_id[(char *)ptr] = current_id; + id_to_token[current_id] = (char *)ptr; + ++current_id; + + } + + ++a_extras_cnt; + DEBUGF(stderr, "Added from auto dictionary: \"%s\"\n", ptr); + + } + + } + + vector<u32> *structure = NULL; + string fn = (char *)filename; + auto entry = file_mapping.find(fn); + + if (entry == file_mapping.end()) { + + // this input file was not analyzed for tokens yet, so let's do it! + + FILE *fp = fopen((char *)filename, "rb"); + if (!fp) { + + s = NULL; + return 0; + + } // should not happen + + fseek(fp, 0, SEEK_END); + size_t len = (size_t)ftell(fp); + + if (len < AFL_TXT_MIN_LEN) { + + fclose(fp); + file_mapping[fn] = structure; // NULL ptr so we don't read the file again + s = NULL; + DEBUGF(stderr, "Too short (%lu) %s\n", len, filename); + return 0; + + } + + string input; + input.resize(len); + rewind(fp); + + if (fread((void *)input.data(), 1, len, fp) != len) { + + s = NULL; + DEBUGF(stderr, "Too short read %s\n", len, filename); + return 0; + + } + + fclose(fp); + + if (!afl_ptr->shm.cmplog_mode) { + + // not running with CMPLOG? bad choice, but whatever ... + // we only want text inputs, so we have to check it ourselves. + + u32 valid_chars = 0; + for (u32 i = 0; i < len; ++i) { + + if (isascii((int)input[i]) || isprint((int)input[i])) { ++valid_chars; } + + } + + // we want at least 95% of text characters ... + if (((len * AFL_TXT_MIN_PERCENT) / 100) > valid_chars) { + + file_mapping[fn] = NULL; + s = NULL; + DEBUGF(stderr, "Not text (%lu) %s\n", len, filename); + return 0; + + } + + } + + // DEBUGF(stderr, "Read %lu bytes for %s\nBefore comment trim:\n%s\n", + // input.size(), filename, input.c_str()); + + if (regex_comment_custom) { + + input = regex_replace(input, *regex_comment_custom, "$2"); + + } else { + + input = regex_replace(input, regex_comment_star, ""); + + } + + DEBUGF(stderr, "After replace %lu bytes for %s\n%s\n", input.size(), + filename, input.c_str()); + + u32 spaces = count(input.begin(), input.end(), ' '); + u32 tabs = count(input.begin(), input.end(), '\t'); + u32 linefeeds = count(input.begin(), input.end(), '\n'); + bool ends_with_linefeed = input[input.length() - 1] == '\n'; + DEBUGF(stderr, "spaces=%u tabs=%u linefeeds=%u ends=%u\n", spaces, tabs, + linefeeds, ends_with_linefeed); + all_spaces += spaces; + all_tabs += tabs; + all_lf += linefeeds; + all_ws = all_spaces + all_tabs + all_lf; + + // now extract all tokens + vector<string> tokens; + string::const_iterator cur = input.begin(), ende = input.end(), found, prev, + match_begin, match_end; + + DEBUGF(stderr, "START!\n"); + + if (likely(!alternative_tokenize)) { + + while (my_search_string(cur, ende, &match_begin, &match_end)) { + + prev = cur; + found = match_begin; + cur = match_end; + + IFDEBUG { + + string foo(match_begin, match_end); + DEBUGF(stderr, + "string %s found at start %lu offset %lu continue at %lu\n", + foo.c_str(), prev - input.begin(), found - prev, + cur - input.begin()); + + } + + if (prev < found) { // there are items between search start and find + while (prev < found) { + + if (isspace(*prev)) { + + auto start = prev; + while (isspace(*prev)) { + + ++prev; + + } + + tokens.push_back(std::string(start, prev)); + DEBUGF(stderr, "WHITESPACE %ld \"%s\"\n", prev - start, + tokens[tokens.size() - 1].c_str()); + + } else if (isalnum(*prev) || *prev == '$' || *prev == '_') { + + auto start = prev; + while (isalnum(*prev) || *prev == '$' || *prev == '_' || + *prev == '.' || *prev == '/') { + + ++prev; + + } + + tokens.push_back(string(start, prev)); + DEBUGF(stderr, "IDENTIFIER %ld \"%s\"\n", prev - start, + tokens[tokens.size() - 1].c_str()); + + } else { + + tokens.push_back(string(prev, prev + 1)); + DEBUGF(stderr, "OTHER \"%c\"\n", *prev); + ++prev; + + } + + } + + } + + tokens.push_back(string(match_begin, match_end)); + DEBUGF(stderr, "TOK: %s\n", tokens[tokens.size() - 1].c_str()); + + } + + DEBUGF(stderr, "AFTER all strings\n"); + + if (cur < ende) { + + while (cur < ende) { + + if (isspace(*cur)) { + + auto start = cur; + while (isspace(*cur)) { + + ++cur; + + } + + tokens.push_back(std::string(start, cur)); + DEBUGF(stderr, "WHITESPACE %ld \"%s\"\n", cur - start, + tokens[tokens.size() - 1].c_str()); + + } else if (isalnum(*cur) || *cur == '$' || *cur == '_') { + + auto start = cur; + while (isalnum(*cur) || *cur == '$' || *cur == '_' || *cur == '.' || + *cur == '/') { + + ++cur; + + } + + tokens.push_back(std::string(start, cur)); + DEBUGF(stderr, "IDENTIFIER %ld \"%s\"\n", cur - start, + tokens[tokens.size() - 1].c_str()); + + } else { + + tokens.push_back(std::string(cur, cur + 1)); + DEBUGF(stderr, "OTHER \"%c\"\n", *cur); + ++cur; + + } + + } + + } + + } else { + + // alternative tokenize + while (my_search_string(cur, ende, &match_begin, &match_end)) { + + prev = cur; + found = match_begin; + cur = match_end; + IFDEBUG { + + string foo(match_begin, match_end); + DEBUGF(stderr, + "string %s found at start %lu offset %lu continue at %lu\n", + foo.c_str(), prev - input.begin(), found - prev, + cur - input.begin()); + + } + + if (prev < found) { // there are items between search start and find + + sregex_token_iterator it{prev, found, regex_whitespace, -1}; + vector<std::string> tokenized{it, {}}; + tokenized.erase(std::remove_if(tokenized.begin(), tokenized.end(), + [](std::string const &s) { + + return s.size() == 0; + + }), + + tokenized.end()); + tokens.reserve(tokens.size() + tokenized.size() * 2 + 1); + + IFDEBUG { + + DEBUGF(stderr, "tokens1: %lu input size: %lu\n", tokenized.size(), + input.size()); + for (auto x : tokenized) { + + cerr << x << endl; + + } + + } + + for (auto token : tokenized) { + + string::const_iterator c = token.begin(), e = token.end(), f, p; + smatch m; + + while (regex_search(c, e, m, regex_word)) { + + p = c; + f = m[0].first; + c = m[0].second; + if (p < f) { + + // there are items between search start and find + while (p < f) { + + IFDEBUG { + + string foo(p, p + 1); + DEBUGF(stderr, "before string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(p, p + 1)); + ++p; + + } + + IFDEBUG { + + string foo(p, f); + DEBUGF(stderr, "before string: \"%s\"\n", foo.c_str()); + tokens.push_back(std::string(p, f)); + + } + + } + + DEBUGF(stderr, + "SUBstring \"%s\" found at start %lu offset %lu continue " + "at %lu\n", + m[0].str().c_str(), p - input.begin(), m.position(), + c - token.begin()); + tokens.push_back(m[0].str()); + + } + + if (c < e) { + + while (c < e) { + + IFDEBUG { + + string foo(c, c + 1); + DEBUGF(stderr, "after string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(c, c + 1)); + ++c; + + } + + IFDEBUG { + + string foo(c, e); + DEBUGF(stderr, "after string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(c, e)); + + } + + } + + } + + tokens.push_back(string(match_begin, match_end)); + + } + + if (cur < ende) { + + sregex_token_iterator it{cur, ende, regex_whitespace, -1}; + vector<std::string> tokenized{it, {}}; + tokenized.erase( + std::remove_if(tokenized.begin(), tokenized.end(), + [](std::string const &s) { return s.size() == 0; }), + tokenized.end()); + tokens.reserve(tokens.size() + tokenized.size() * 2 + 1); + + IFDEBUG { + + DEBUGF(stderr, "tokens2: %lu input size: %lu\n", tokenized.size(), + input.size()); + for (auto x : tokenized) { + + cerr << x << endl; + + } + + } + + for (auto token : tokenized) { + + string::const_iterator c = token.begin(), e = token.end(), f, p; + smatch m; + + while (regex_search(c, e, m, regex_word)) { + + p = c; + f = m[0].first; + c = m[0].second; + if (p < f) { + + // there are items between search start and find + while (p < f) { + + IFDEBUG { + + string foo(p, p + 1); + DEBUGF(stderr, "before string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(p, p + 1)); + ++p; + + } + + IFDEBUG { + + string foo(p, f); + DEBUGF(stderr, "before string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(p, f)); + + } + + DEBUGF(stderr, + "SUB2string \"%s\" found at start %lu offset %lu continue " + "at %lu\n", + m[0].str().c_str(), p - input.begin(), m.position(), + c - token.begin()); + tokens.push_back(m[0].str()); + + } + + if (c < e) { + + while (c < e) { + + IFDEBUG { + + string foo(c, c + 1); + DEBUGF(stderr, "after string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(c, c + 1)); + ++c; + + } + + IFDEBUG { + + string foo(c, e); + DEBUGF(stderr, "after string: \"%s\"\n", foo.c_str()); + + } + + tokens.push_back(std::string(c, e)); + + } + + } + + } + + } + + IFDEBUG { + + DEBUGF(stderr, "DUMPING TOKENS:\n"); + u32 size_1 = tokens.size() - 1; + for (u32 i = 0; i < tokens.size(); ++i) { + + DEBUGF(stderr, "%s", tokens[i].c_str()); + if (unlikely(alternative_tokenize && i < size_1)) { + + DEBUGF(stderr, "%s", whitespace.c_str()); + + } + + } + + DEBUGF(stderr, "---------------------------\n"); + + } + + if (tokens.size() < AUTOTOKENS_SIZE_MIN) { + + file_mapping[fn] = NULL; + s = NULL; + DEBUGF(stderr, "too few tokens\n"); + return 0; + + } + + /* Now we transform the tokens into an ID list and saved that */ + + structure = new vector<u32>(); + u32 id; + + for (u32 i = 0; i < tokens.size(); ++i) { + + if ((id = token_to_id[tokens[i]]) == 0) { + + // First time we see this token, add it to the list + token_to_id[tokens[i]] = current_id; + id_to_token[current_id] = tokens[i]; + structure->push_back(current_id); + ++current_id; + + } else { + + structure->push_back(id); + + } + + } + + // save the token structure to the file mapping + file_mapping[fn] = structure; + id_mapping[valid_structures] = structure; + ++valid_structures; + s = structure; + all_structure_items += structure->size(); + + // we are done! + DEBUGF(stderr, "DONE! We have %lu tokens in the structure\n", + structure->size()); + + } + + else { + + if (entry->second == NULL) { + + DEBUGF(stderr, "Skipping %s\n", filename); + s = NULL; + return 0; + + } + + s = entry->second; + DEBUGF(stderr, "OK %s\n", filename); + + } + + return 1; // we always fuzz unless non-ascii or too small + +} + +extern "C" my_mutator_t *afl_custom_init(afl_state *afl, unsigned int seed) { + + (void)(seed); + my_mutator_t *data = (my_mutator_t *)calloc(1, sizeof(my_mutator_t)); + if (!data) { + + perror("afl_custom_init alloc"); + return NULL; + + } + + if (getenv("AUTOTOKENS_DEBUG")) { debug = 1; } + if (getenv("AUTOTOKENS_ONLY_FAV")) { only_fav = 1; } + if (getenv("AUTOTOKENS_ALTERNATIVE_TOKENIZE")) { alternative_tokenize = 1; } + if (getenv("AUTOTOKENS_WHITESPACE")) { + + whitespace = getenv("AUTOTOKENS_WHITESPACE"); + + } + + if (getenv("AUTOTOKENS_COMMENT")) { + + char buf[256]; + snprintf(buf, sizeof(buf), "(%s.*)([\r\n]?)", getenv("AUTOTOKENS_COMMENT")); + regex_comment_custom = new regex(buf, regex::optimize); + + } + + data->afl = afl_ptr = afl; + + // set common whitespace tokens + // we deliberately do not put uncommon ones here to these will count as + // identifier tokens. + if (!alternative_tokenize) { + + token_to_id[" "] = current_id; + id_to_token[current_id] = " "; + ++current_id; + token_to_id["\t"] = current_id; + id_to_token[current_id] = "\t"; + ++current_id; + token_to_id["\n"] = current_id; + id_to_token[current_id] = "\n"; + ++current_id; + token_to_id["\r\n"] = current_id; + id_to_token[current_id] = "\r\n"; + ++current_id; + token_to_id[" \n"] = current_id; + id_to_token[current_id] = " \n"; + ++current_id; + token_to_id[" "] = current_id; + id_to_token[current_id] = " "; + ++current_id; + token_to_id["\t\t"] = current_id; + id_to_token[current_id] = "\t\t"; + ++current_id; + token_to_id["\n\n"] = current_id; + id_to_token[current_id] = "\n\n"; + ++current_id; + token_to_id["\r\n\r\n"] = current_id; + id_to_token[current_id] = "\r\n\r\n"; + ++current_id; + token_to_id[" "] = current_id; + id_to_token[current_id] = " "; + ++current_id; + token_to_id["\t\t\t\t"] = current_id; + id_to_token[current_id] = "\t\t\t\t"; + ++current_id; + token_to_id["\n\n\n\n"] = current_id; + id_to_token[current_id] = "\n\n\n\n"; + ++current_id; + whitespace_ids = current_id; + token_to_id["\""] = current_id; + id_to_token[current_id] = "\""; + ++current_id; + token_to_id["'"] = current_id; + id_to_token[current_id] = "'"; + ++current_id; + + } + + return data; + +} + +extern "C" void afl_custom_splice_optout(my_mutator_t *data) { + + (void)(data); + +} + +extern "C" void afl_custom_deinit(my_mutator_t *data) { + + /* we use this to print statistics at exit :-) + needs to be stderr as stdout is filtered */ + + fprintf(stderr, + "\n\nAutotoken mutator statistics:\n" + " Number of all seen tokens: %u\n" + " Number of input structures: %u\n" + " Number of all items in structures: %llu\n" + " Number of total fuzzes: %llu\n\n", + current_id - 1, valid_structures, all_structure_items, fuzz_count); + + free(data); + +} + diff --git a/custom_mutators/examples/custom_send.c b/custom_mutators/examples/custom_send.c index ffea927e..7de72819 100644 --- a/custom_mutators/examples/custom_send.c +++ b/custom_mutators/examples/custom_send.c @@ -1,7 +1,14 @@ +// +// This is an example on how to use afl_custom_send +// It writes each mutated data set to /tmp/foo +// You can modify this to send to IPC, shared memory, etc. +// // cc -O3 -fPIC -shared -g -o custom_send.so -I../../include custom_send.c // cd ../.. // afl-cc -o test-instr test-instr.c -// afl-fuzz -i in -o out -- ./test-instr -f /tmp/foo +// AFL_CUSTOM_MUTATOR_LIBRARY=custom_mutators/examples/custom_send.so \ +// afl-fuzz -i in -o out -- ./test-instr -f /tmp/foo +// #include "custom_mutator_helpers.h" diff --git a/custom_mutators/examples/example.c b/custom_mutators/examples/example.c index 3f299508..e680ec8e 100644 --- a/custom_mutators/examples/example.c +++ b/custom_mutators/examples/example.c @@ -6,7 +6,7 @@ Dominik Maier <mail@dmnk.co> */ -// You need to use -I /path/to/AFLplusplus/include +// You need to use -I/path/to/AFLplusplus/include -I. #include "custom_mutator_helpers.h" #include <stdint.h> @@ -118,6 +118,8 @@ size_t afl_custom_fuzz(my_mutator_t *data, uint8_t *buf, size_t buf_size, } + if (max_size > mutated_size) { mutated_size = max_size; } + *out_buf = mutated_out; return mutated_size; diff --git a/custom_mutators/examples/post_library_gif.so.c b/custom_mutators/examples/post_library_gif.so.c index 9cd224f4..3cb018a6 100644 --- a/custom_mutators/examples/post_library_gif.so.c +++ b/custom_mutators/examples/post_library_gif.so.c @@ -129,8 +129,8 @@ size_t afl_custom_post_process(post_state_t *data, unsigned char *in_buf, /* Allocate memory for new buffer, reusing previous allocation if possible. Note we have to use afl-fuzz's own realloc! - Note that you should only do this if you need to grow the buffer, - otherwise work with in_buf, and assign it to *out_buf instead. */ + We use afl_realloc because it is effective. + You can also work within in_buf, and assign it to *out_buf. */ *out_buf = afl_realloc(out_buf, len); |