diff options
| author | Can Celik <ogulcancelik@gmail.com> | 2026-04-04 19:22:04 +0300 |
|---|---|---|
| committer | Can Celik <ogulcancelik@gmail.com> | 2026-04-05 01:23:06 +0300 |
| commit | 41dd733ca7123c9ac4bfc6c781697a660e95b052 (patch) | |
| tree | 3fc91815ca139ef2e0b281bba0abda4ef15175f4 /vendor/libghostty-vt/pkg/afl++/afl.c | |
| parent | 55c138263e190a1e79d4b997bfb9397306c0ec1f (diff) | |
feat: finish ghostty pane backend integration
Diffstat (limited to 'vendor/libghostty-vt/pkg/afl++/afl.c')
| -rw-r--r-- | vendor/libghostty-vt/pkg/afl++/afl.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/vendor/libghostty-vt/pkg/afl++/afl.c b/vendor/libghostty-vt/pkg/afl++/afl.c new file mode 100644 index 00000000..61eb12c4 --- /dev/null +++ b/vendor/libghostty-vt/pkg/afl++/afl.c @@ -0,0 +1,141 @@ +#include <limits.h> +#include <signal.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +// AFL++ fuzzer harness for Zig fuzz targets. +// +// This file is the C "glue" that connects AFL++'s runtime to Zig-defined +// fuzz test functions. We can't use AFL++'s compiler wrappers (afl-clang, +// afl-gcc) because the code under test is compiled with Zig, so we manually +// expand the AFL macros (__AFL_INIT, __AFL_LOOP, __AFL_FUZZ_INIT, etc.) and +// wire up the sanitizer coverage symbols ourselves. + +// To ensure checks are not optimized out it is recommended to disable +// code optimization for the fuzzer harness main() +#pragma clang optimize off +#pragma GCC optimize("O0") + +// Zig-exported entry points. zig_fuzz_init() performs one-time setup and +// zig_fuzz_test() runs one fuzz iteration on the given input buffer. +// The Zig object should export these. +void zig_fuzz_init(); +void zig_fuzz_test(unsigned char*, size_t); + +// Linker-provided symbols marking the boundaries of the __sancov_guards +// section. These must be declared extern so the linker provides the actual +// section boundaries from the instrumented code, rather than creating new +// variables that shadow them. On macOS (Mach-O), the linker uses a different +// naming convention for section boundaries than Linux (ELF), so we use asm +// labels to reference them. +#ifdef __APPLE__ +extern uint32_t __start___sancov_guards __asm( + "section$start$__DATA$__sancov_guards"); +extern uint32_t __stop___sancov_guards __asm( + "section$end$__DATA$__sancov_guards"); +#else +extern uint32_t __start___sancov_guards; +extern uint32_t __stop___sancov_guards; +#endif + +// Provided by afl-compiler-rt; initializes the guard array used by +// SanitizerCoverage's trace-pc-guard instrumentation mode. +void __sanitizer_cov_trace_pc_guard_init(uint32_t*, uint32_t*); + +// Stubs for sanitizer coverage callbacks that the Zig-compiled code references +// but AFL's runtime (afl-compiler-rt) does not provide. Without these, linking +// would fail with undefined symbol errors. +__attribute__((visibility("default"))) __attribute__(( + tls_model("initial-exec"))) _Thread_local uintptr_t __sancov_lowest_stack; +void __sanitizer_cov_trace_pc_indir() {} +void __sanitizer_cov_8bit_counters_init() {} +void __sanitizer_cov_pcs_init() {} + +// Manual expansion of __AFL_FUZZ_INIT(). +// +// Enables shared-memory fuzzing: AFL++ writes test cases directly into +// shared memory (__afl_fuzz_ptr) instead of passing them via stdin, which +// is much faster. When not running under AFL++ (e.g. standalone execution), +// __afl_fuzz_ptr will be NULL and we fall back to reading from stdin into +// __afl_fuzz_alt (a 1 MB static buffer). +int __afl_sharedmem_fuzzing = 1; +extern __attribute__((visibility("default"))) unsigned int* __afl_fuzz_len; +extern __attribute__((visibility("default"))) unsigned char* __afl_fuzz_ptr; +unsigned char __afl_fuzz_alt[1048576]; +unsigned char* __afl_fuzz_alt_ptr = __afl_fuzz_alt; + +int main(int argc, char** argv) { + // Tell AFL's coverage runtime about our guard section so it can track + // which edges in the instrumented Zig code have been hit. + __sanitizer_cov_trace_pc_guard_init(&__start___sancov_guards, + &__stop___sancov_guards); + + // Manual expansion of __AFL_INIT() — deferred fork server mode. + // + // The magic string "##SIG_AFL_DEFER_FORKSRV##" is embedded in the binary + // so AFL++'s tooling can detect that this harness uses deferred fork + // server initialization. The `volatile` + `used` attributes prevent the + // compiler/linker from stripping it. We then call __afl_manual_init() to + // start the fork server at this point (after our setup) rather than at + // the very beginning of main(). + static volatile const char* _A __attribute__((used, unused)); + _A = (const char*)"##SIG_AFL_DEFER_FORKSRV##"; +#ifdef __APPLE__ + __attribute__((visibility("default"))) void _I(void) __asm__( + "___afl_manual_init"); +#else + __attribute__((visibility("default"))) void _I(void) __asm__( + "__afl_manual_init"); +#endif + _I(); + + zig_fuzz_init(); + + // Manual expansion of __AFL_FUZZ_TESTCASE_BUF. + // Use shared memory buffer if available, otherwise fall back to the + // static buffer (for standalone/non-AFL execution). + unsigned char* buf = __afl_fuzz_ptr ? __afl_fuzz_ptr : __afl_fuzz_alt_ptr; + + // Manual expansion of __AFL_LOOP(UINT_MAX) — persistent mode loop. + // + // Persistent mode keeps the process alive across many test cases instead + // of fork()'ing for each one, dramatically improving throughput. The magic + // string "##SIG_AFL_PERSISTENT##" signals to AFL++ that this binary + // supports persistent mode. __afl_persistent_loop() returns non-zero + // while there are more inputs to process. + // + // When connected to AFL++, we loop UINT_MAX times (essentially forever, + // AFL will restart us periodically). When running standalone, we loop + // once so the harness can be used for manual testing/reproduction. + while (({ + static volatile const char* _B __attribute__((used, unused)); + _B = (const char*)"##SIG_AFL_PERSISTENT##"; + extern __attribute__((visibility("default"))) int __afl_connected; +#ifdef __APPLE__ + __attribute__((visibility("default"))) int _L(unsigned int) __asm__( + "___afl_persistent_loop"); +#else + __attribute__((visibility("default"))) int _L(unsigned int) __asm__( + "__afl_persistent_loop"); +#endif + _L(__afl_connected ? UINT_MAX : 1); + })) { + // Manual expansion of __AFL_FUZZ_TESTCASE_LEN. + // In shared-memory mode, the length is provided directly by AFL++. + // In standalone mode, we read from stdin into the fallback buffer. + int len = + __afl_fuzz_ptr ? *__afl_fuzz_len + : (*__afl_fuzz_len = read(0, __afl_fuzz_alt_ptr, 1048576)) == 0xffffffff + ? 0 + : *__afl_fuzz_len; + + if (len >= 0) { + zig_fuzz_test(buf, len); + } + } + + return 0; +} |
