1 /* Capstone Disassembler Engine */
2 /* By David Hogarty, 2014 */
3
4 // the following must precede stdio (woo, thanks msft)
5 #if defined(_MSC_VER) && _MSC_VER < 1900
6 #define _CRT_SECURE_NO_WARNINGS
7 #define snprintf _snprintf
8 #endif
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12
13 #include <platform.h>
14 #include <capstone.h>
15
16 static csh handle;
17
18 struct platform {
19 cs_arch arch;
20 cs_mode mode;
21 unsigned char *code;
22 size_t size;
23 char *comment;
24 int syntax;
25 };
26
hex_string(unsigned char * str,size_t len)27 static char *hex_string(unsigned char *str, size_t len)
28 {
29 // returns a malloced string that has the hex version of the string in it
30 // null if failed to malloc
31 char *hex_out;
32 size_t i;
33
34 hex_out = (char *) malloc(len*2 + 1); // two ascii characters per input character, plus trailing null
35 if (!hex_out) { goto Exit; }
36
37 for (i = 0; i < len; ++i) {
38 snprintf(hex_out + (i*2), 2, "%02x", str[i]);
39 }
40
41 hex_out[len*2] = 0; // trailing null
42
43 Exit:
44 return hex_out;
45 }
46
snprint_insn_detail(char * buf,size_t * cur,size_t * left,cs_insn * ins)47 static void snprint_insn_detail(char * buf, size_t * cur, size_t * left, cs_insn *ins)
48 {
49 size_t used = 0;
50
51 #define _this_printf(...) \
52 { \
53 size_t used = 0; \
54 used = snprintf(buf + *cur, *left, __VA_ARGS__); \
55 *left -= used; \
56 *cur += used; \
57 }
58
59 cs_arm *arm;
60 int i;
61
62 // detail can be NULL on "data" instruction if SKIPDATA option is turned ON
63 if (ins->detail == NULL)
64 return;
65
66 arm = &(ins->detail->arm);
67
68 if (arm->op_count)
69 _this_printf("\top_count: %u\n", arm->op_count);
70
71 for (i = 0; i < arm->op_count; i++) {
72 cs_arm_op *op = &(arm->operands[i]);
73 switch((int)op->type) {
74 default:
75 break;
76 case ARM_OP_REG:
77 _this_printf("\t\toperands[%u].type: REG = %s\n", i, cs_reg_name(handle, op->reg));
78 break;
79 case ARM_OP_IMM:
80 _this_printf("\t\toperands[%u].type: IMM = 0x%x\n", i, op->imm);
81 break;
82 case ARM_OP_FP:
83 _this_printf("\t\toperands[%u].type: FP = %f\n", i, op->fp);
84 break;
85 case ARM_OP_MEM:
86 _this_printf("\t\toperands[%u].type: MEM\n", i);
87 if (op->mem.base != X86_REG_INVALID)
88 _this_printf("\t\t\toperands[%u].mem.base: REG = %s\n",
89 i, cs_reg_name(handle, op->mem.base));
90 if (op->mem.index != X86_REG_INVALID)
91 _this_printf("\t\t\toperands[%u].mem.index: REG = %s\n",
92 i, cs_reg_name(handle, op->mem.index));
93 if (op->mem.scale != 1)
94 _this_printf("\t\t\toperands[%u].mem.scale: %u\n", i, op->mem.scale);
95 if (op->mem.disp != 0)
96 _this_printf("\t\t\toperands[%u].mem.disp: 0x%x\n", i, op->mem.disp);
97
98 break;
99 case ARM_OP_PIMM:
100 _this_printf("\t\toperands[%u].type: P-IMM = %u\n", i, op->imm);
101 break;
102 case ARM_OP_CIMM:
103 _this_printf("\t\toperands[%u].type: C-IMM = %u\n", i, op->imm);
104 break;
105 }
106
107 if (op->shift.type != ARM_SFT_INVALID && op->shift.value) {
108 if (op->shift.type < ARM_SFT_ASR_REG) {
109 // shift with constant value
110 _this_printf("\t\t\tShift: %u = %u\n", op->shift.type, op->shift.value);
111 } else {
112 // shift with register
113 _this_printf("\t\t\tShift: %u = %s\n", op->shift.type,
114 cs_reg_name(handle, op->shift.value));
115 }
116 }
117 }
118
119 if (arm->cc != ARM_CC_AL && arm->cc != ARM_CC_INVALID) {
120 _this_printf("\tCode condition: %u\n", arm->cc);
121 }
122
123 if (arm->update_flags) {
124 _this_printf("\tUpdate-flags: True\n");
125 }
126
127 if (arm->writeback) {
128 _this_printf("\tWrite-back: True\n");
129 }
130
131 #undef _this_printf
132 }
133
print_insn_detail(cs_insn * ins)134 static void print_insn_detail(cs_insn *ins)
135 {
136 char a_buf[2048];
137 size_t cur=0, left=2048;
138 snprint_insn_detail(a_buf, &cur, &left, ins);
139 printf("%s\n", a_buf);
140 }
141
142 struct invalid_code {
143 unsigned char *code;
144 size_t size;
145 char *comment;
146 };
147
148 #define MAX_INVALID_CODES 16
149
150 struct invalid_instructions {
151 cs_arch arch;
152 cs_mode mode;
153 char *platform_comment;
154 int num_invalid_codes;
155 struct invalid_code invalid_codes[MAX_INVALID_CODES];
156 };
157
test_invalids()158 static void test_invalids()
159 {
160 struct invalid_instructions invalids[] = {{
161 CS_ARCH_ARM,
162 CS_MODE_THUMB,
163 "Thumb",
164 1,
165 {{
166 (unsigned char *)"\xbd\xe8\x1e\xff",
167 4,
168 "invalid thumb2 pop because sp used and because both pc and lr are "
169 "present at the same time"
170 }},
171 }};
172
173 struct invalid_instructions * invalid = NULL;
174
175 uint64_t address = 0x1000;
176 cs_insn *insn;
177 int i;
178 int j;
179 size_t count;
180
181 printf("\nShould be invalid\n"
182 "-----------------\n");
183
184 for (i = 0; i < sizeof(invalids)/sizeof(invalids[0]); i++) {
185 cs_err err;
186
187 invalid = invalids + i;
188 err = cs_open(invalid->arch, invalid->mode, &handle);
189
190 if (err) {
191 printf("Failed on cs_open() with error returned: %u\n", err);
192 continue;
193 }
194
195 cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
196 cs_option(handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_NOREGNAME);
197
198 for (j = 0; j < invalid->num_invalid_codes; ++j) {
199 struct invalid_code *invalid_code = NULL;
200 char *hex_str = NULL;
201
202 invalid_code = invalid->invalid_codes + j;
203
204 hex_str = hex_string(invalid_code->code, invalid_code->size);
205
206 printf("%s %s: %s\n", invalid->platform_comment, hex_str, invalid_code->comment);
207
208 free(hex_str);
209
210 count = cs_disasm(handle,
211 invalid_code->code, invalid_code->size, address, 0, &insn
212 );
213
214 if (count) {
215 size_t k;
216 printf(" ERROR:\n");
217
218 for (k = 0; k < count; k++) {
219 printf(" 0x%"PRIx64":\t%s\t%s\n",
220 insn[k].address, insn[k].mnemonic, insn[k].op_str);
221 print_insn_detail(&insn[k]);
222 }
223 cs_free(insn, count);
224
225 } else {
226 printf(" SUCCESS: invalid\n");
227 }
228 }
229
230 cs_close(&handle);
231 }
232 }
233
234 struct valid_code {
235 unsigned char *code;
236 size_t size;
237 uint32_t start_addr;
238 char *expected_out;
239 char *comment;
240 };
241
242 #define MAX_VALID_CODES 16
243 struct valid_instructions {
244 cs_arch arch;
245 cs_mode mode;
246 char *platform_comment;
247 int num_valid_codes;
248 struct valid_code valid_codes[MAX_VALID_CODES];
249 };
250
test_valids()251 static void test_valids()
252 {
253 struct valid_instructions valids[] = {{
254 CS_ARCH_ARM,
255 CS_MODE_THUMB,
256 "Thumb",
257 3,
258 {{ (unsigned char *)"\x00\xf0\x26\xe8", 4, 0x352,
259 "0x352:\tblx\t#0x3a0\n"
260 "\top_count: 1\n"
261 "\t\toperands[0].type: IMM = 0x3a0\n",
262
263 "thumb2 blx with misaligned immediate"
264 }, { (unsigned char *)"\x05\xdd", 2, 0x1f0,
265 "0x1f0:\tble\t#0x1fe\n"
266 "\top_count: 1\n"
267 "\t\toperands[0].type: IMM = 0x1fe\n"
268 "\tCode condition: 14\n",
269
270 "thumb b cc with thumb-aligned target"
271 }, { (unsigned char *)"\xbd\xe8\xf0\x8f", 4, 0,
272 "0x0:\tpop.w\t{r4, r5, r6, r7, r8, r9, r10, r11, pc}\n"
273 "\top_count: 9\n"
274 "\t\toperands[0].type: REG = r4\n"
275 "\t\toperands[1].type: REG = r5\n"
276 "\t\toperands[2].type: REG = r6\n"
277 "\t\toperands[3].type: REG = r7\n"
278 "\t\toperands[4].type: REG = r8\n"
279 "\t\toperands[5].type: REG = r9\n"
280 "\t\toperands[6].type: REG = r10\n"
281 "\t\toperands[7].type: REG = r11\n"
282 "\t\toperands[8].type: REG = pc\n",
283
284 "thumb2 pop that should be valid"
285 },
286 }
287 }};
288
289 struct valid_instructions * valid = NULL;
290
291 uint64_t address = 0x1000;
292 cs_insn *insn;
293 int i;
294 int j;
295 size_t count;
296
297
298 for (i = 0; i < sizeof(valids)/sizeof(valids[0]); i++) {
299 cs_err err;
300
301 valid = valids + i;
302 err = cs_open(valid->arch, valid->mode, &handle);
303
304 if (err) {
305 printf("Failed on cs_open() with error returned: %u\n", err);
306 continue;
307 }
308
309 cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
310 cs_option(handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_NOREGNAME);
311
312 #define _this_printf(...) \
313 { \
314 size_t used = 0; \
315 used = snprintf(tmp_buf + cur, left, __VA_ARGS__); \
316 left -= used; \
317 cur += used; \
318 }
319 printf("\nShould be valid\n"
320 "---------------\n");
321
322 for (j = 0; j < valid->num_valid_codes; ++j) {
323 char tmp_buf[2048];
324 size_t left = 2048;
325 size_t cur = 0;
326 size_t used = 0;
327 int success = 0;
328 char * hex_str = NULL;
329
330 struct valid_code * valid_code = NULL;
331 valid_code = valid->valid_codes + j;
332
333 hex_str = hex_string(valid_code->code, valid_code->size);
334
335 printf("%s %s @ 0x%04x: %s\n %s",
336 valid->platform_comment, hex_str, valid_code->start_addr,
337 valid_code->comment, valid_code->expected_out);
338
339 count = cs_disasm(handle,
340 valid_code->code, valid_code->size,
341 valid_code->start_addr, 0, &insn
342 );
343
344 if (count) {
345 size_t k;
346 size_t max_len = 0;
347 size_t tmp_len = 0;
348
349 for (k = 0; k < count; k++) {
350 _this_printf(
351 "0x%"PRIx64":\t%s\t%s\n",
352 insn[k].address, insn[k].mnemonic,
353 insn[k].op_str
354 );
355
356 snprint_insn_detail(tmp_buf, &cur, &left, &insn[k]);
357 }
358
359 max_len = strlen(tmp_buf);
360 tmp_len = strlen(valid_code->expected_out);
361 if (tmp_len > max_len) {
362 max_len = tmp_len;
363 }
364
365 if (memcmp(tmp_buf, valid_code->expected_out, max_len)) {
366 printf(
367 " ERROR: '''\n%s''' does not match"
368 " expected '''\n%s'''\n",
369 tmp_buf, valid_code->expected_out
370 );
371 } else {
372 printf(" SUCCESS: valid\n");
373 }
374
375 cs_free(insn, count);
376
377 } else {
378 printf("ERROR: invalid\n");
379 }
380 }
381
382 cs_close(&handle);
383 }
384
385 #undef _this_prinf
386 }
387
main()388 int main()
389 {
390 test_invalids();
391 test_valids();
392 return 0;
393 }
394
395