forked from AFLplusplus/AFLplusplus
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathafl-ld-lto.c
358 lines (243 loc) · 8.94 KB
/
afl-ld-lto.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
/*
american fuzzy lop++ - wrapper for llvm 11+ lld
-----------------------------------------------
Written by Marc Heuse <[email protected]> for afl++
Maintained by Marc Heuse <[email protected]>,
Heiko Eißfeldt <[email protected]>
Andrea Fioraldi <[email protected]>
Dominik Maier <[email protected]>
Copyright 2019-2020 AFLplusplus Project. 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
The sole purpose of this wrapper is to preprocess clang LTO files when
linking with lld and performing the instrumentation on the whole program.
*/
#define AFL_MAIN
#define _GNU_SOURCE
#include "config.h"
#include "types.h"
#include "debug.h"
#include "alloc-inl.h"
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <dirent.h>
#define MAX_PARAM_COUNT 4096
static u8 **ld_params; /* Parameters passed to the real 'ld' */
static u8 *afl_path = AFL_PATH;
static u8 *real_ld = AFL_REAL_LD;
static u8 be_quiet, /* Quiet mode (no stderr output) */
debug, /* AFL_DEBUG */
passthrough, /* AFL_LD_PASSTHROUGH - no link+optimize*/
just_version; /* Just show version? */
static u32 ld_param_cnt = 1; /* Number of params to 'ld' */
/* Examine and modify parameters to pass to 'ld', 'llvm-link' and 'llmv-ar'.
Note that the file name is always the last parameter passed by GCC,
so we exploit this property to keep the code "simple". */
static void edit_params(int argc, char **argv) {
u32 i, instrim = 0, gold_pos = 0, gold_present = 0, rt_present = 0,
rt_lto_present = 0, inst_present = 0;
char *ptr;
ld_params = ck_alloc(4096 * sizeof(u8 *));
ld_params[0] = (u8 *)real_ld;
if (!passthrough) {
for (i = 1; i < argc; i++) {
if (strstr(argv[i], "/afl-llvm-rt-lto.o") != NULL) rt_lto_present = 1;
if (strstr(argv[i], "/afl-llvm-rt.o") != NULL) rt_present = 1;
if (strstr(argv[i], "/afl-llvm-lto-instr") != NULL) inst_present = 1;
}
for (i = 1; i < argc && !gold_pos; i++) {
if (strcmp(argv[i], "-plugin") == 0) {
if (strncmp(argv[i], "-plugin=", strlen("-plugin=")) == 0) {
if (strcasestr(argv[i], "LLVMgold.so") != NULL)
gold_present = gold_pos = i + 1;
} else if (i < argc && strcasestr(argv[i + 1], "LLVMgold.so") != NULL) {
gold_present = gold_pos = i + 2;
}
}
}
if (!gold_pos) {
for (i = 1; i + 1 < argc && !gold_pos; i++) {
if (argv[i][0] != '-') {
if (argv[i - 1][0] == '-') {
switch (argv[i - 1][1]) {
case 'b':
break;
case 'd':
break;
case 'e':
break;
case 'F':
break;
case 'f':
break;
case 'I':
break;
case 'l':
break;
case 'L':
break;
case 'm':
break;
case 'o':
break;
case 'O':
break;
case 'p':
if (index(argv[i - 1], '=') == NULL) gold_pos = i;
break;
case 'R':
break;
case 'T':
break;
case 'u':
break;
case 'y':
break;
case 'z':
break;
case '-': {
if (strcmp(argv[i - 1], "--oformat") == 0) break;
if (strcmp(argv[i - 1], "--output") == 0) break;
if (strncmp(argv[i - 1], "--opt-remarks-", 14) == 0) break;
gold_pos = i;
break;
}
default:
gold_pos = i;
}
} else
gold_pos = i;
}
}
}
if (!gold_pos) gold_pos = 1;
}
if (getenv("AFL_LLVM_INSTRIM"))
instrim = 1;
else if ((ptr = getenv("AFL_LLVM_INSTRUMENT")) &&
(strcasestr(ptr, "CFG") == 0 || strcasestr(ptr, "INSTRIM") == 0))
instrim = 1;
if (debug)
SAYF(cMGN "[D] " cRST
"passthrough=%s instrim=%d, gold_pos=%d, gold_present=%s "
"inst_present=%s rt_present=%s rt_lto_present=%s\n",
passthrough ? "true" : "false", instrim, gold_pos,
gold_present ? "true" : "false", inst_present ? "true" : "false",
rt_present ? "true" : "false", rt_lto_present ? "true" : "false");
for (i = 1; i < argc; i++) {
if (ld_param_cnt >= MAX_PARAM_COUNT)
FATAL(
"Too many command line parameters because of unpacking .a archives, "
"this would need to be done by hand ... sorry! :-(");
if (strcmp(argv[i], "--afl") == 0) {
if (!be_quiet) OKF("afl++ test command line flag detected, exiting.");
exit(0);
}
if (i == gold_pos && !passthrough) {
ld_params[ld_param_cnt++] = alloc_printf("-L%s/../lib", LLVM_BINDIR);
if (!gold_present) {
ld_params[ld_param_cnt++] = "-plugin";
ld_params[ld_param_cnt++] =
alloc_printf("%s/../lib/LLVMgold.so", LLVM_BINDIR);
}
ld_params[ld_param_cnt++] = "--allow-multiple-definition";
if (!inst_present) {
if (instrim)
ld_params[ld_param_cnt++] =
alloc_printf("-mllvm=-load=%s/afl-llvm-lto-instrim.so", afl_path);
else
ld_params[ld_param_cnt++] = alloc_printf(
"-mllvm=-load=%s/afl-llvm-lto-instrumentation.so", afl_path);
}
if (!rt_present)
ld_params[ld_param_cnt++] = alloc_printf("%s/afl-llvm-rt.o", afl_path);
if (!rt_lto_present)
ld_params[ld_param_cnt++] =
alloc_printf("%s/afl-llvm-rt-lto.o", afl_path);
}
ld_params[ld_param_cnt++] = argv[i];
}
ld_params[ld_param_cnt] = NULL;
}
/* Main entry point */
int main(int argc, char **argv) {
s32 pid, i, status;
u8 * ptr;
char thecwd[PATH_MAX];
if ((ptr = getenv("AFL_LD_CALLER")) != NULL) {
FATAL("ld loop detected! Set AFL_REAL_LD!\n");
}
if (isatty(2) && !getenv("AFL_QUIET") && !getenv("AFL_DEBUG")) {
SAYF(cCYA "afl-ld-to" VERSION cRST
" by Marc \"vanHauser\" Heuse <[email protected]>\n");
} else
be_quiet = 1;
if (getenv("AFL_DEBUG") != NULL) debug = 1;
if (getenv("AFL_PATH") != NULL) afl_path = getenv("AFL_PATH");
if (getenv("AFL_LD_PASSTHROUGH") != NULL) passthrough = 1;
if (getenv("AFL_REAL_LD") != NULL) real_ld = getenv("AFL_REAL_LD");
if (!afl_path || !*afl_path) afl_path = "/usr/local/lib/afl";
setenv("AFL_LD_CALLER", "1", 1);
if (debug) {
if (getcwd(thecwd, sizeof(thecwd)) != 0) strcpy(thecwd, ".");
SAYF(cMGN "[D] " cRST "cd \"%s\";", thecwd);
for (i = 0; i < argc; i++)
SAYF(" \"%s\"", argv[i]);
SAYF("\n");
}
if (argc < 2) {
SAYF(
"\n"
"This is a helper application for afl-clang-lto. It is a wrapper "
"around GNU "
"llvm's 'lld',\n"
"executed by the toolchain whenever using "
"afl-clang-lto/afl-clang-lto++.\n"
"You probably don't want to run this program directly but rather pass "
"it as LD parameter to configure scripts\n\n"
"Environment variables:\n"
" AFL_LD_PASSTHROUGH do not link+optimize == no instrumentation\n"
" AFL_REAL_LD point to the real llvm 11 lld if necessary\n"
"\nafl-ld-to was compiled with the fixed real 'ld' of %s and the "
"binary path of %s\n\n",
real_ld, LLVM_BINDIR);
exit(1);
}
edit_params(argc, argv); // here most of the magic happens :-)
if (debug) {
SAYF(cMGN "[D]" cRST " cd \"%s\";", thecwd);
for (i = 0; i < ld_param_cnt; i++)
SAYF(" \"%s\"", ld_params[i]);
SAYF("\n");
}
if (!(pid = fork())) {
if (strlen(real_ld) > 1) execvp(real_ld, (char **)ld_params);
execvp("ld", (char **)ld_params); // fallback
FATAL("Oops, failed to execute 'ld' - check your PATH");
}
if (pid < 0) PFATAL("fork() failed");
if (waitpid(pid, &status, 0) <= 0) PFATAL("waitpid() failed");
if (debug) SAYF(cMGN "[D] " cRST "linker result: %d\n", status);
if (!just_version) {
if (status == 0) {
if (!be_quiet) OKF("Linker was successful");
} else {
SAYF(cLRD "[-] " cRST
"Linker failed, please investigate and send a bug report. Most "
"likely an 'ld' option is incompatible with %s.\n",
AFL_CLANG_FLTO);
}
}
exit(WEXITSTATUS(status));
}