cfd23479 |
1 | #include <stdio.h> |
2 | #include <stdlib.h> |
3 | #include <string.h> |
4 | #include <linux/coff.h> |
5 | #include <assert.h> |
6 | #include <stdint.h> |
7 | |
ede51255 |
8 | #include "my_assert.h" |
9 | |
cfd23479 |
10 | /* http://www.delorie.com/djgpp/doc/coff/ */ |
11 | |
12 | typedef struct { |
13 | unsigned short f_magic; /* magic number */ |
14 | unsigned short f_nscns; /* number of sections */ |
15 | unsigned int f_timdat; /* time & date stamp */ |
16 | unsigned int f_symptr; /* file pointer to symtab */ |
17 | unsigned int f_nsyms; /* number of symtab entries */ |
18 | unsigned short f_opthdr; /* sizeof(optional hdr) */ |
19 | unsigned short f_flags; /* flags */ |
20 | } FILHDR; |
21 | |
22 | typedef struct { |
23 | unsigned short magic; /* type of file */ |
24 | unsigned short vstamp; /* version stamp */ |
25 | unsigned int tsize; /* text size in bytes, padded to FW bdry*/ |
26 | unsigned int dsize; /* initialized data " " */ |
27 | unsigned int bsize; /* uninitialized data " " */ |
28 | unsigned int entry; /* entry pt. */ |
29 | unsigned int text_start; /* base of text used for this file */ |
30 | unsigned int data_start; /* base of data used for this file */ |
31 | } AOUTHDR; |
32 | |
33 | typedef struct { |
34 | char s_name[8]; /* section name */ |
35 | unsigned int s_paddr; /* physical address, aliased s_nlib */ |
36 | unsigned int s_vaddr; /* virtual address */ |
37 | unsigned int s_size; /* section size */ |
38 | unsigned int s_scnptr; /* file ptr to raw data for section */ |
39 | unsigned int s_relptr; /* file ptr to relocation */ |
40 | unsigned int s_lnnoptr; /* file ptr to line numbers */ |
41 | unsigned short s_nreloc; /* number of relocation entries */ |
42 | unsigned short s_nlnno; /* number of line number entries */ |
43 | unsigned int s_flags; /* flags */ |
44 | } SCNHDR; |
45 | |
46 | typedef struct { |
47 | unsigned int r_vaddr; /* address of relocation */ |
48 | unsigned int r_symndx; /* symbol we're adjusting for */ |
49 | unsigned short r_type; /* type of relocation */ |
50 | } __attribute__((packed)) RELOC; |
51 | |
e86c9ee6 |
52 | typedef struct { |
53 | union { |
54 | char e_name[E_SYMNMLEN]; |
55 | struct { |
56 | unsigned int e_zeroes; |
57 | unsigned int e_offset; |
58 | } e; |
59 | } e; |
60 | unsigned int e_value; |
61 | short e_scnum; |
62 | unsigned short e_type; |
63 | unsigned char e_sclass; |
64 | unsigned char e_numaux; |
65 | } __attribute__((packed)) SYMENT; |
66 | |
67 | #define C_EXT 2 |
68 | |
69 | struct my_symtab { |
70 | unsigned int addr; |
a2f78da4 |
71 | //unsigned int fpos; // for patching |
72 | unsigned int is_text:1; |
e86c9ee6 |
73 | char *name; |
74 | }; |
75 | |
572a6bea |
76 | struct my_sect_info { |
77 | long scnhdr_fofs; |
78 | long sect_fofs; |
79 | long reloc_fofs; |
80 | uint8_t *data; |
81 | long size; |
82 | RELOC *relocs; |
83 | long reloc_cnt; |
84 | }; |
85 | |
e86c9ee6 |
86 | static int symt_cmp(const void *p1_, const void *p2_) |
87 | { |
88 | const struct my_symtab *p1 = p1_, *p2 = p2_; |
89 | return p1->addr - p2->addr; |
90 | } |
91 | |
cfd23479 |
92 | void parse_headers(FILE *f, unsigned int *base_out, |
572a6bea |
93 | struct my_sect_info *sect_i, |
a2f78da4 |
94 | struct my_symtab **symtab_out, long *sym_cnt, |
95 | struct my_symtab **raw_symtab_out, long *raw_sym_cnt) |
cfd23479 |
96 | { |
a2f78da4 |
97 | struct my_symtab *symt_txt = NULL; |
98 | struct my_symtab *symt_all = NULL; |
e86c9ee6 |
99 | char *stringtab = NULL; |
cfd23479 |
100 | unsigned int base = 0; |
e86c9ee6 |
101 | int text_scnum = 0; |
102 | long filesize; |
103 | char symname[9]; |
cfd23479 |
104 | long opthdr_pos; |
105 | long reloc_size; |
106 | FILHDR hdr; |
107 | AOUTHDR opthdr; |
108 | SCNHDR scnhdr; |
e86c9ee6 |
109 | SYMENT syment; |
110 | int i, s, val; |
cfd23479 |
111 | int ret; |
112 | |
e86c9ee6 |
113 | ret = fseek(f, 0, SEEK_END); |
114 | my_assert(ret, 0); |
115 | |
116 | filesize = ftell(f); |
117 | |
118 | ret = fseek(f, 0, SEEK_SET); |
119 | my_assert(ret, 0); |
120 | |
cfd23479 |
121 | ret = fread(&hdr, 1, sizeof(hdr), f); |
122 | my_assert(ret, sizeof(hdr)); |
123 | |
124 | if (hdr.f_magic == 0x5a4d) // MZ |
125 | { |
126 | ret = fseek(f, 0x3c, SEEK_SET); |
127 | my_assert(ret, 0); |
128 | ret = fread(&val, 1, sizeof(val), f); |
129 | my_assert(ret, sizeof(val)); |
130 | |
131 | ret = fseek(f, val, SEEK_SET); |
132 | my_assert(ret, 0); |
133 | ret = fread(&val, 1, sizeof(val), f); |
134 | my_assert(ret, sizeof(val)); |
135 | my_assert(val, 0x4550); // PE |
136 | |
137 | // should be COFF now |
138 | ret = fread(&hdr, 1, sizeof(hdr), f); |
139 | my_assert(ret, sizeof(hdr)); |
140 | } |
141 | |
142 | my_assert(hdr.f_magic, COFF_I386MAGIC); |
143 | |
144 | if (hdr.f_opthdr != 0) |
145 | { |
146 | opthdr_pos = ftell(f); |
147 | |
148 | if (hdr.f_opthdr < sizeof(opthdr)) |
149 | my_assert(1, 0); |
150 | |
151 | ret = fread(&opthdr, 1, sizeof(opthdr), f); |
152 | my_assert(ret, sizeof(opthdr)); |
153 | my_assert(opthdr.magic, COFF_ZMAGIC); |
154 | |
2c605b97 |
155 | //printf("text_start: %x\n", opthdr.text_start); |
cfd23479 |
156 | |
157 | if (hdr.f_opthdr > sizeof(opthdr)) { |
158 | ret = fread(&base, 1, sizeof(base), f); |
159 | my_assert(ret, sizeof(base)); |
2c605b97 |
160 | //printf("base: %x\n", base); |
cfd23479 |
161 | } |
162 | ret = fseek(f, opthdr_pos + hdr.f_opthdr, SEEK_SET); |
163 | my_assert(ret, 0); |
164 | } |
165 | |
e86c9ee6 |
166 | // note: assuming first non-empty one is .text .. |
cfd23479 |
167 | for (s = 0; s < hdr.f_nscns; s++) { |
572a6bea |
168 | sect_i->scnhdr_fofs = ftell(f); |
169 | |
cfd23479 |
170 | ret = fread(&scnhdr, 1, sizeof(scnhdr), f); |
171 | my_assert(ret, sizeof(scnhdr)); |
172 | |
e86c9ee6 |
173 | if (scnhdr.s_size != 0) { |
174 | text_scnum = s + 1; |
cfd23479 |
175 | break; |
e86c9ee6 |
176 | } |
cfd23479 |
177 | } |
572a6bea |
178 | my_assert(s < hdr.f_nscns, 1); |
cfd23479 |
179 | |
2c605b97 |
180 | #if 0 |
e86c9ee6 |
181 | printf("f_nsyms: %x\n", hdr.f_nsyms); |
cfd23479 |
182 | printf("s_name: '%s'\n", scnhdr.s_name); |
183 | printf("s_vaddr: %x\n", scnhdr.s_vaddr); |
184 | printf("s_size: %x\n", scnhdr.s_size); |
e86c9ee6 |
185 | //printf("s_scnptr: %x\n", scnhdr.s_scnptr); |
cfd23479 |
186 | printf("s_nreloc: %x\n", scnhdr.s_nreloc); |
187 | printf("--\n"); |
2c605b97 |
188 | #endif |
cfd23479 |
189 | |
190 | ret = fseek(f, scnhdr.s_scnptr, SEEK_SET); |
191 | my_assert(ret, 0); |
192 | |
572a6bea |
193 | sect_i->data = malloc(scnhdr.s_size); |
194 | my_assert_not(sect_i->data, NULL); |
195 | ret = fread(sect_i->data, 1, scnhdr.s_size, f); |
cfd23479 |
196 | my_assert(ret, scnhdr.s_size); |
197 | |
572a6bea |
198 | sect_i->sect_fofs = scnhdr.s_scnptr; |
199 | sect_i->size = scnhdr.s_size; |
cfd23479 |
200 | |
e86c9ee6 |
201 | // relocs |
cfd23479 |
202 | ret = fseek(f, scnhdr.s_relptr, SEEK_SET); |
203 | my_assert(ret, 0); |
204 | |
572a6bea |
205 | reloc_size = scnhdr.s_nreloc * sizeof(sect_i->relocs[0]); |
206 | sect_i->relocs = malloc(reloc_size + 1); |
207 | my_assert_not(sect_i->relocs, NULL); |
208 | ret = fread(sect_i->relocs, 1, reloc_size, f); |
cfd23479 |
209 | my_assert(ret, reloc_size); |
210 | |
572a6bea |
211 | sect_i->reloc_cnt = scnhdr.s_nreloc; |
212 | sect_i->reloc_fofs = scnhdr.s_relptr; |
213 | |
214 | if (base != 0 && base_out != NULL) |
215 | *base_out = base + scnhdr.s_vaddr; |
216 | |
217 | if (symtab_out == NULL || sym_cnt == NULL) |
218 | return; |
cfd23479 |
219 | |
e86c9ee6 |
220 | // symtab |
221 | if (hdr.f_nsyms != 0) { |
222 | symname[8] = 0; |
223 | |
a2f78da4 |
224 | symt_txt = malloc(hdr.f_nsyms * sizeof(symt_txt[0]) + 1); |
225 | my_assert_not(symt_txt, NULL); |
226 | symt_all = malloc(hdr.f_nsyms * sizeof(symt_all[0]) + 1); |
227 | my_assert_not(symt_all, NULL); |
e86c9ee6 |
228 | |
229 | ret = fseek(f, hdr.f_symptr |
230 | + hdr.f_nsyms * sizeof(syment), SEEK_SET); |
231 | my_assert(ret, 0); |
232 | ret = fread(&i, 1, sizeof(i), f); |
233 | my_assert(ret, sizeof(i)); |
234 | my_assert((unsigned int)i < filesize, 1); |
235 | |
236 | stringtab = malloc(i); |
237 | my_assert_not(stringtab, NULL); |
238 | memset(stringtab, 0, 4); |
239 | ret = fread(stringtab + 4, 1, i - 4, f); |
240 | my_assert(ret, i - 4); |
241 | |
242 | ret = fseek(f, hdr.f_symptr, SEEK_SET); |
243 | my_assert(ret, 0); |
244 | } |
245 | |
246 | for (i = s = 0; i < hdr.f_nsyms; i++) { |
a2f78da4 |
247 | //long pos = ftell(f); |
e86c9ee6 |
248 | |
249 | ret = fread(&syment, 1, sizeof(syment), f); |
250 | my_assert(ret, sizeof(syment)); |
251 | |
252 | strncpy(symname, syment.e.e_name, 8); |
253 | //printf("%3d %2d %08x '%s'\n", syment.e_sclass, |
254 | // syment.e_scnum, syment.e_value, symname); |
255 | |
a2f78da4 |
256 | symt_all[i].addr = syment.e_value; |
257 | //symt_all[i].fpos = pos; |
e86c9ee6 |
258 | if (syment.e.e.e_zeroes == 0) |
a2f78da4 |
259 | symt_all[i].name = stringtab + syment.e.e.e_offset; |
e86c9ee6 |
260 | else |
a2f78da4 |
261 | symt_all[i].name = strdup(symname); |
262 | |
263 | symt_all[i].is_text = (syment.e_scnum == text_scnum); |
264 | if (symt_all[i].is_text && syment.e_sclass == C_EXT) { |
265 | symt_txt[s] = symt_all[i]; |
266 | s++; |
267 | } |
e86c9ee6 |
268 | |
269 | if (syment.e_numaux) { |
270 | ret = fseek(f, syment.e_numaux * sizeof(syment), |
271 | SEEK_CUR); |
272 | my_assert(ret, 0); |
273 | i += syment.e_numaux; |
274 | } |
275 | } |
276 | |
a2f78da4 |
277 | if (symt_txt != NULL) |
278 | qsort(symt_txt, s, sizeof(symt_txt[0]), symt_cmp); |
e86c9ee6 |
279 | |
280 | *sym_cnt = s; |
a2f78da4 |
281 | *symtab_out = symt_txt; |
282 | *raw_sym_cnt = i; |
283 | *raw_symtab_out = symt_all; |
cfd23479 |
284 | } |
285 | |
286 | static int handle_pad(uint8_t *d_obj, uint8_t *d_exe, int maxlen) |
287 | { |
288 | static const uint8_t p7[7] = { 0x8d, 0xa4, 0x24, 0x00, 0x00, 0x00, 0x00 }; |
289 | static const uint8_t p6[6] = { 0x8d, 0x9b, 0x00, 0x00, 0x00, 0x00 }; |
3ebea2cf |
290 | static const uint8_t p5[5] = { 0x05, 0x00, 0x00, 0x00, 0x00 }; // add eax, 0 |
291 | static const uint8_t p4[4] = { 0x8d, 0x64, 0x24, 0x00 }; // lea |
292 | static const uint8_t p3[3] = { 0x8d, 0x49, 0x00 }; // lea ecx, [ecx] |
293 | static const uint8_t p2[2] = { 0x8b, 0xff }; // mov edi, edi |
294 | static const uint8_t p1[1] = { 0x90 }; // nop |
cfd23479 |
295 | int len; |
296 | int i; |
297 | |
298 | for (i = 0; i < maxlen; i++) |
299 | if (d_exe[i] != 0xcc) |
300 | break; |
301 | |
302 | for (len = i; len > 0; ) |
303 | { |
304 | i = len; |
305 | if (i > 7) |
306 | i = 7; |
307 | |
308 | switch (i) { |
309 | #define CASE(x) \ |
310 | case sizeof(p ## x): \ |
311 | if (memcmp(d_obj, p ## x, sizeof(p ## x))) \ |
312 | return 0; \ |
313 | memset(d_obj, 0xcc, sizeof(p ## x)); \ |
314 | break; |
315 | CASE(7) |
316 | CASE(6) |
317 | CASE(5) |
318 | CASE(4) |
319 | CASE(3) |
320 | CASE(2) |
321 | CASE(1) |
322 | default: |
323 | printf("%s: unhandled len: %d\n", __func__, len); |
324 | return 0; |
325 | #undef CASE |
326 | } |
327 | |
328 | len -= i; |
329 | d_obj += i; |
330 | } |
331 | |
332 | return 1; |
333 | } |
334 | |
335 | struct equiv_opcode { |
336 | signed char len; |
337 | signed char ofs; |
338 | short cmp_rm; |
339 | uint8_t v_masm[8]; |
340 | uint8_t v_masm_mask[8]; |
341 | uint8_t v_msvc[8]; |
342 | uint8_t v_msvc_mask[8]; |
343 | } equiv_ops[] = { |
344 | // cmp $0x11,%ax |
345 | { 4, -1, 0, |
346 | { 0x66,0x83,0xf8,0x03 }, { 0xff,0xff,0xff,0x00 }, |
347 | { 0x66,0x3d,0x03,0x00 }, { 0xff,0xff,0x00,0xff }, }, |
348 | // lea -0x1(%ebx,%eax,1),%esi // op mod/rm sib offs |
349 | // mov, test, imm grp 1 |
350 | { 3, -2, 1, |
351 | { 0x8d,0x74,0x03 }, { 0xf0,0x07,0xc0 }, |
352 | { 0x8d,0x74,0x18 }, { 0xf0,0x07,0xc0 }, }, |
353 | // movzbl 0x58f24a(%eax,%ecx,1),%eax |
354 | { 4, -3, 1, |
355 | { 0x0f,0xb6,0x84,0x08 }, { 0xff,0xff,0x07,0xc0 }, |
356 | { 0x0f,0xb6,0x84,0x01 }, { 0xff,0xff,0x07,0xc0 }, }, |
357 | // inc/dec |
358 | { 3, -2, 1, |
359 | { 0xfe,0x4c,0x03 }, { 0xfe,0xff,0xc0 }, |
360 | { 0xfe,0x4c,0x18 }, { 0xfe,0xff,0xc0 }, }, |
361 | // cmp |
362 | { 3, -2, 1, |
363 | { 0x38,0x0c,0x0c }, { 0xff,0xff,0xc0 }, |
364 | { 0x38,0x0c,0x30 }, { 0xff,0xff,0xc0 }, }, |
365 | // test %dl,%bl |
366 | { 2, -1, 1, |
367 | { 0x84,0xd3 }, { 0xfe,0xc0 }, |
368 | { 0x84,0xda }, { 0xfe,0xc0 }, }, |
369 | // cmp r,r/m vs rm/r |
370 | { 2, 0, 1, |
371 | { 0x3a,0xca }, { 0xff,0xc0 }, |
372 | { 0x38,0xd1 }, { 0xff,0xc0 }, }, |
373 | // rep + 66 prefix |
374 | { 2, 0, 0, |
375 | { 0xf3,0x66 }, { 0xfe,0xff }, |
376 | { 0x66,0xf3 }, { 0xff,0xfe }, }, |
377 | // fadd st, st(0) vs st(0), st |
378 | { 2, 0, 0, |
379 | { 0xd8,0xc0 }, { 0xff,0xf7 }, |
380 | { 0xdc,0xc0 }, { 0xff,0xf7 }, }, |
381 | |
382 | // broad filters (may take too much..) |
383 | // testb $0x4,0x1d(%esi,%eax,1) |
384 | // movb, push, .. |
385 | { 3, -2, 1, |
386 | { 0xf6,0x44,0x06 }, { 0x00,0x07,0xc0 }, |
387 | { 0xf6,0x44,0x30 }, { 0x00,0x07,0xc0 }, }, |
388 | }; |
389 | |
390 | static int cmp_mask(uint8_t *d, uint8_t *expect, uint8_t *mask, int len) |
391 | { |
392 | int i; |
393 | |
394 | for (i = 0; i < len; i++) |
395 | if ((d[i] & mask[i]) != (expect[i] & mask[i])) |
396 | return 1; |
397 | |
398 | return 0; |
399 | } |
400 | |
401 | static int check_equiv(uint8_t *d_obj, uint8_t *d_exe, int maxlen) |
402 | { |
403 | uint8_t vo, ve, vo2, ve2; |
404 | int i, jo, je; |
405 | int len, ofs; |
406 | |
407 | for (i = 0; i < sizeof(equiv_ops) / sizeof(equiv_ops[0]); i++) |
408 | { |
409 | struct equiv_opcode *op = &equiv_ops[i]; |
410 | |
411 | len = op->len; |
412 | if (maxlen < len) |
413 | continue; |
414 | |
415 | ofs = op->ofs; |
416 | if (cmp_mask(d_obj + ofs, op->v_masm, |
417 | op->v_masm_mask, len)) |
418 | continue; |
419 | if (cmp_mask(d_exe + ofs, op->v_msvc, |
420 | op->v_msvc_mask, len)) |
421 | continue; |
422 | |
423 | jo = je = 0; |
424 | d_obj += ofs; |
425 | d_exe += ofs; |
426 | while (1) |
427 | { |
428 | for (; jo < len; jo++) |
429 | if (op->v_masm_mask[jo] != 0xff) |
430 | break; |
431 | for (; je < len; je++) |
432 | if (op->v_msvc_mask[je] != 0xff) |
433 | break; |
434 | |
435 | if ((jo == len && je != len) || (jo != len && je == len)) { |
436 | printf("invalid equiv_ops\n"); |
437 | return -1; |
438 | } |
439 | if (jo == len) |
440 | return len + ofs - 1; // matched |
441 | |
442 | // var byte |
443 | vo = d_obj[jo] & ~op->v_masm_mask[jo]; |
444 | ve = d_exe[je] & ~op->v_msvc_mask[je]; |
445 | if (op->cmp_rm && op->v_masm_mask[jo] == 0xc0) { |
446 | vo2 = vo >> 3; |
447 | vo &= 7; |
448 | ve2 = ve & 7; |
449 | ve >>= 3; |
450 | if (vo != ve || vo2 != ve2) |
451 | return -1; |
452 | } |
453 | else { |
454 | if (vo != ve) |
455 | return -1; |
456 | } |
457 | |
458 | jo++; |
459 | je++; |
460 | } |
461 | } |
462 | |
463 | return -1; |
464 | } |
465 | |
572a6bea |
466 | static void fill_int3(unsigned char *d, int len) |
467 | { |
468 | while (len-- > 0) { |
a2f78da4 |
469 | if (d[0] == 0xcc && d[1] == 0xcc) |
572a6bea |
470 | break; |
471 | *d++ = 0xcc; |
472 | } |
473 | } |
474 | |
cfd23479 |
475 | int main(int argc, char *argv[]) |
476 | { |
de50b98b |
477 | unsigned int base = 0, addr, end, sym, *t; |
572a6bea |
478 | struct my_sect_info s_text_obj, s_text_exe; |
a2f78da4 |
479 | struct my_symtab *raw_syms_obj = NULL; |
572a6bea |
480 | struct my_symtab *syms_obj = NULL; |
a2f78da4 |
481 | long sym_cnt_obj, raw_sym_cnt_obj; |
cfd23479 |
482 | FILE *f_obj, *f_exe; |
572a6bea |
483 | SCNHDR tmphdr; |
484 | long sztext_cmn; |
cfd23479 |
485 | int retval = 1; |
486 | int left; |
487 | int ret; |
488 | int i; |
489 | |
490 | if (argc != 3) { |
e86c9ee6 |
491 | printf("usage:\n%s <a_obj> <exe>\n", argv[0]); |
cfd23479 |
492 | return 1; |
493 | } |
494 | |
495 | f_obj = fopen(argv[1], "r+b"); |
496 | if (f_obj == NULL) { |
3ebea2cf |
497 | fprintf(stderr, "%s: ", argv[1]); |
cfd23479 |
498 | perror(""); |
499 | return 1; |
500 | } |
501 | |
502 | f_exe = fopen(argv[2], "r"); |
503 | if (f_exe == NULL) { |
3ebea2cf |
504 | fprintf(stderr, "%s: ", argv[2]); |
cfd23479 |
505 | perror(""); |
506 | return 1; |
507 | } |
508 | |
a2f78da4 |
509 | parse_headers(f_obj, NULL, &s_text_obj, &syms_obj, &sym_cnt_obj, |
510 | &raw_syms_obj, &raw_sym_cnt_obj); |
511 | parse_headers(f_exe, &base, &s_text_exe, NULL, NULL, NULL, NULL); |
cfd23479 |
512 | |
572a6bea |
513 | sztext_cmn = s_text_obj.size; |
514 | if (sztext_cmn > s_text_exe.size) |
515 | sztext_cmn = s_text_exe.size; |
cfd23479 |
516 | |
517 | if (sztext_cmn == 0) { |
518 | printf("bad .text size(s): %ld, %ld\n", |
572a6bea |
519 | s_text_obj.size, s_text_exe.size); |
cfd23479 |
520 | return 1; |
521 | } |
522 | |
572a6bea |
523 | for (i = 0; i < s_text_obj.reloc_cnt; i++) |
cfd23479 |
524 | { |
572a6bea |
525 | unsigned int a = s_text_obj.relocs[i].r_vaddr; |
526 | //printf("%04x %08x\n", s_text_obj.relocs[i].r_type, a); |
cfd23479 |
527 | |
572a6bea |
528 | switch (s_text_obj.relocs[i].r_type) { |
2c605b97 |
529 | case 0x06: // RELOC_ADDR32 |
530 | case 0x14: // RELOC_REL32 |
531 | // must preserve stored val, |
572a6bea |
532 | // so trash exe so that cmp passes |
533 | memcpy(s_text_exe.data + a, s_text_obj.data + a, 4); |
cfd23479 |
534 | break; |
535 | default: |
2c605b97 |
536 | printf("unknown reloc %x @%08x/%08x\n", |
572a6bea |
537 | s_text_obj.relocs[i].r_type, a, base + a); |
cfd23479 |
538 | return 1; |
539 | } |
540 | } |
541 | |
542 | for (i = 0; i < sztext_cmn; i++) |
543 | { |
572a6bea |
544 | if (s_text_obj.data[i] == s_text_exe.data[i]) |
cfd23479 |
545 | continue; |
546 | |
547 | left = sztext_cmn - i; |
548 | |
572a6bea |
549 | if (s_text_exe.data[i] == 0xcc) { // padding |
550 | if (handle_pad(s_text_obj.data + i, |
551 | s_text_exe.data + i, left)) |
cfd23479 |
552 | continue; |
553 | } |
554 | |
572a6bea |
555 | ret = check_equiv(s_text_obj.data + i, s_text_exe.data + i, left); |
cfd23479 |
556 | if (ret >= 0) { |
557 | i += ret; |
558 | continue; |
559 | } |
560 | |
572a6bea |
561 | printf("%x: %02x vs %02x\n", base + i, |
562 | s_text_obj.data[i], s_text_exe.data[i]); |
cfd23479 |
563 | goto out; |
564 | } |
565 | |
572a6bea |
566 | // fill removed funcs with 'int3' |
2c605b97 |
567 | for (i = 0; i < sym_cnt_obj; i++) { |
568 | if (strncmp(syms_obj[i].name, "rm_", 3)) |
569 | continue; |
570 | |
571 | addr = syms_obj[i].addr; |
572 | end = (i < sym_cnt_obj - 1) |
572a6bea |
573 | ? syms_obj[i + 1].addr : s_text_obj.size; |
574 | if (addr >= s_text_obj.size || end > s_text_obj.size) { |
2c605b97 |
575 | printf("addr OOR: %x-%x '%s'\n", addr, end, |
576 | syms_obj[i].name); |
577 | goto out; |
578 | } |
572a6bea |
579 | fill_int3(s_text_obj.data + addr, end - addr); |
580 | } |
581 | |
582 | // remove relocs |
583 | for (i = 0; i < s_text_obj.reloc_cnt; i++) { |
584 | addr = s_text_obj.relocs[i].r_vaddr; |
a2f78da4 |
585 | sym = s_text_obj.relocs[i].r_symndx; |
572a6bea |
586 | if (addr > s_text_obj.size - 4) { |
587 | printf("reloc addr OOR: %x\n", addr); |
588 | goto out; |
589 | } |
a2f78da4 |
590 | if (sym >= raw_sym_cnt_obj) { |
591 | printf("reloc sym OOR: %d/%ld\n", |
592 | sym, raw_sym_cnt_obj); |
593 | goto out; |
594 | } |
595 | #if 0 |
596 | printf("r %08x -> %08x %s\n", base + addr, |
597 | raw_syms_obj[sym].addr, |
598 | raw_syms_obj[sym].name); |
599 | #endif |
600 | t = (unsigned int *)(s_text_obj.data + addr); |
601 | if (t[0] == 0xcccccccc |
602 | || t[-1] == 0xcccccccc) { // jumptab of a func? |
603 | t[0] = 0xcccccccc; |
572a6bea |
604 | memmove(&s_text_obj.relocs[i], |
605 | &s_text_obj.relocs[i + 1], |
606 | (s_text_obj.reloc_cnt - i - 1) |
607 | * sizeof(s_text_obj.relocs[0])); |
608 | i--; |
609 | s_text_obj.reloc_cnt--; |
610 | } |
de50b98b |
611 | #if 0 |
a2f78da4 |
612 | // note: branches/calls already linked, |
613 | // so only useful for dd refs |
de50b98b |
614 | // XXX: rm'd because of switch tables |
a2f78da4 |
615 | else if (raw_syms_obj[sym].is_text) { |
de50b98b |
616 | unsigned int addr2 = raw_syms_obj[sym].addr; |
a2f78da4 |
617 | if (s_text_obj.data[addr2] == 0xcc) { |
618 | printf("warning: reloc %08x -> %08x " |
619 | "points to rm'd target '%s'\n", |
620 | base + addr, base + addr2, |
621 | raw_syms_obj[sym].name); |
622 | } |
623 | } |
de50b98b |
624 | #endif |
2c605b97 |
625 | } |
626 | |
572a6bea |
627 | // patch .text |
628 | ret = fseek(f_obj, s_text_obj.sect_fofs, SEEK_SET); |
629 | my_assert(ret, 0); |
630 | ret = fwrite(s_text_obj.data, 1, s_text_obj.size, f_obj); |
631 | my_assert(ret, s_text_obj.size); |
632 | |
633 | // patch relocs |
634 | ret = fseek(f_obj, s_text_obj.reloc_fofs, SEEK_SET); |
635 | my_assert(ret, 0); |
636 | ret = fwrite(s_text_obj.relocs, sizeof(s_text_obj.relocs[0]), |
637 | s_text_obj.reloc_cnt, f_obj); |
638 | my_assert(ret, s_text_obj.reloc_cnt); |
639 | |
640 | ret = fseek(f_obj, s_text_obj.scnhdr_fofs, SEEK_SET); |
641 | my_assert(ret, 0); |
642 | ret = fread(&tmphdr, 1, sizeof(tmphdr), f_obj); |
643 | my_assert(ret, sizeof(tmphdr)); |
644 | |
645 | tmphdr.s_nreloc = s_text_obj.reloc_cnt; |
646 | |
647 | ret = fseek(f_obj, s_text_obj.scnhdr_fofs, SEEK_SET); |
648 | my_assert(ret, 0); |
649 | ret = fwrite(&tmphdr, 1, sizeof(tmphdr), f_obj); |
650 | my_assert(ret, sizeof(tmphdr)); |
2c605b97 |
651 | |
652 | fclose(f_obj); |
653 | fclose(f_exe); |
654 | |
655 | retval = 0; |
cfd23479 |
656 | out: |
657 | return retval; |
658 | } |