| 1 | /* simple-object-mach-o.c -- routines to manipulate Mach-O object files. |
| 2 | Copyright (C) 2010-2019 Free Software Foundation, Inc. |
| 3 | Written by Ian Lance Taylor, Google. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify it |
| 6 | under the terms of the GNU General Public License as published by the |
| 7 | Free Software Foundation; either version 2, or (at your option) any |
| 8 | later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, write to the Free Software |
| 17 | Foundation, 51 Franklin Street - Fifth Floor, |
| 18 | Boston, MA 02110-1301, USA. */ |
| 19 | |
| 20 | #include "config.h" |
| 21 | #include "libiberty.h" |
| 22 | #include "simple-object.h" |
| 23 | |
| 24 | #include <stddef.h> |
| 25 | |
| 26 | #ifdef HAVE_STDLIB_H |
| 27 | #include <stdlib.h> |
| 28 | #endif |
| 29 | |
| 30 | #ifdef HAVE_STDINT_H |
| 31 | #include <stdint.h> |
| 32 | #endif |
| 33 | |
| 34 | #ifdef HAVE_STRING_H |
| 35 | #include <string.h> |
| 36 | #endif |
| 37 | |
| 38 | #ifdef HAVE_INTTYPES_H |
| 39 | #include <inttypes.h> |
| 40 | #endif |
| 41 | |
| 42 | #include "simple-object-common.h" |
| 43 | |
| 44 | /* Mach-O structures and constants. */ |
| 45 | |
| 46 | /* Mach-O header (32-bit version). */ |
| 47 | |
| 48 | struct mach_o_header_32 |
| 49 | { |
| 50 | unsigned char magic[4]; /* Magic number. */ |
| 51 | unsigned char cputype[4]; /* CPU that this object is for. */ |
| 52 | unsigned char cpusubtype[4]; /* CPU subtype. */ |
| 53 | unsigned char filetype[4]; /* Type of file. */ |
| 54 | unsigned char ncmds[4]; /* Number of load commands. */ |
| 55 | unsigned char sizeofcmds[4]; /* Total size of load commands. */ |
| 56 | unsigned char flags[4]; /* Flags for special featues. */ |
| 57 | }; |
| 58 | |
| 59 | /* Mach-O header (64-bit version). */ |
| 60 | |
| 61 | struct mach_o_header_64 |
| 62 | { |
| 63 | unsigned char magic[4]; /* Magic number. */ |
| 64 | unsigned char cputype[4]; /* CPU that this object is for. */ |
| 65 | unsigned char cpusubtype[4]; /* CPU subtype. */ |
| 66 | unsigned char filetype[4]; /* Type of file. */ |
| 67 | unsigned char ncmds[4]; /* Number of load commands. */ |
| 68 | unsigned char sizeofcmds[4]; /* Total size of load commands. */ |
| 69 | unsigned char flags[4]; /* Flags for special featues. */ |
| 70 | unsigned char reserved[4]; /* Reserved. Duh. */ |
| 71 | }; |
| 72 | |
| 73 | /* For magic field in header. */ |
| 74 | |
| 75 | #define MACH_O_MH_MAGIC 0xfeedface |
| 76 | #define MACH_O_MH_MAGIC_64 0xfeedfacf |
| 77 | |
| 78 | /* For filetype field in header. */ |
| 79 | |
| 80 | #define MACH_O_MH_OBJECT 0x01 |
| 81 | |
| 82 | /* A Mach-O file is a list of load commands. This is the header of a |
| 83 | load command. */ |
| 84 | |
| 85 | struct mach_o_load_command |
| 86 | { |
| 87 | unsigned char cmd[4]; /* The type of load command. */ |
| 88 | unsigned char cmdsize[4]; /* Size in bytes of entire command. */ |
| 89 | }; |
| 90 | |
| 91 | /* For cmd field in load command. */ |
| 92 | |
| 93 | #define MACH_O_LC_SEGMENT 0x01 |
| 94 | #define MACH_O_LC_SEGMENT_64 0x19 |
| 95 | |
| 96 | /* LC_SEGMENT load command. */ |
| 97 | |
| 98 | struct mach_o_segment_command_32 |
| 99 | { |
| 100 | unsigned char cmd[4]; /* The type of load command (LC_SEGMENT). */ |
| 101 | unsigned char cmdsize[4]; /* Size in bytes of entire command. */ |
| 102 | unsigned char segname[16]; /* Name of this segment. */ |
| 103 | unsigned char vmaddr[4]; /* Virtual memory address of this segment. */ |
| 104 | unsigned char vmsize[4]; /* Size there, in bytes. */ |
| 105 | unsigned char fileoff[4]; /* Offset in bytes of the data to be mapped. */ |
| 106 | unsigned char filesize[4]; /* Size in bytes on disk. */ |
| 107 | unsigned char maxprot[4]; /* Maximum permitted vmem protection. */ |
| 108 | unsigned char initprot[4]; /* Initial vmem protection. */ |
| 109 | unsigned char nsects[4]; /* Number of sections in this segment. */ |
| 110 | unsigned char flags[4]; /* Flags that affect the loading. */ |
| 111 | }; |
| 112 | |
| 113 | /* LC_SEGMENT_64 load command. */ |
| 114 | |
| 115 | struct mach_o_segment_command_64 |
| 116 | { |
| 117 | unsigned char cmd[4]; /* The type of load command (LC_SEGMENT_64). */ |
| 118 | unsigned char cmdsize[4]; /* Size in bytes of entire command. */ |
| 119 | unsigned char segname[16]; /* Name of this segment. */ |
| 120 | unsigned char vmaddr[8]; /* Virtual memory address of this segment. */ |
| 121 | unsigned char vmsize[8]; /* Size there, in bytes. */ |
| 122 | unsigned char fileoff[8]; /* Offset in bytes of the data to be mapped. */ |
| 123 | unsigned char filesize[8]; /* Size in bytes on disk. */ |
| 124 | unsigned char maxprot[4]; /* Maximum permitted vmem protection. */ |
| 125 | unsigned char initprot[4]; /* Initial vmem protection. */ |
| 126 | unsigned char nsects[4]; /* Number of sections in this segment. */ |
| 127 | unsigned char flags[4]; /* Flags that affect the loading. */ |
| 128 | }; |
| 129 | |
| 130 | /* 32-bit section header. */ |
| 131 | |
| 132 | struct mach_o_section_32 |
| 133 | { |
| 134 | unsigned char sectname[16]; /* Section name. */ |
| 135 | unsigned char segname[16]; /* Segment that the section belongs to. */ |
| 136 | unsigned char addr[4]; /* Address of this section in memory. */ |
| 137 | unsigned char size[4]; /* Size in bytes of this section. */ |
| 138 | unsigned char offset[4]; /* File offset of this section. */ |
| 139 | unsigned char align[4]; /* log2 of this section's alignment. */ |
| 140 | unsigned char reloff[4]; /* File offset of this section's relocs. */ |
| 141 | unsigned char nreloc[4]; /* Number of relocs for this section. */ |
| 142 | unsigned char flags[4]; /* Section flags/attributes. */ |
| 143 | unsigned char reserved1[4]; |
| 144 | unsigned char reserved2[4]; |
| 145 | }; |
| 146 | |
| 147 | /* 64-bit section header. */ |
| 148 | |
| 149 | struct mach_o_section_64 |
| 150 | { |
| 151 | unsigned char sectname[16]; /* Section name. */ |
| 152 | unsigned char segname[16]; /* Segment that the section belongs to. */ |
| 153 | unsigned char addr[8]; /* Address of this section in memory. */ |
| 154 | unsigned char size[8]; /* Size in bytes of this section. */ |
| 155 | unsigned char offset[4]; /* File offset of this section. */ |
| 156 | unsigned char align[4]; /* log2 of this section's alignment. */ |
| 157 | unsigned char reloff[4]; /* File offset of this section's relocs. */ |
| 158 | unsigned char nreloc[4]; /* Number of relocs for this section. */ |
| 159 | unsigned char flags[4]; /* Section flags/attributes. */ |
| 160 | unsigned char reserved1[4]; |
| 161 | unsigned char reserved2[4]; |
| 162 | unsigned char reserved3[4]; |
| 163 | }; |
| 164 | |
| 165 | /* Flags for Mach-O sections. */ |
| 166 | |
| 167 | #define MACH_O_S_ATTR_DEBUG 0x02000000 |
| 168 | |
| 169 | /* The length of a segment or section name. */ |
| 170 | |
| 171 | #define MACH_O_NAME_LEN (16) |
| 172 | |
| 173 | /* A GNU specific extension for long section names. */ |
| 174 | |
| 175 | #define GNU_SECTION_NAMES "__section_names" |
| 176 | |
| 177 | /* A GNU-specific extension to wrap multiple sections using three |
| 178 | mach-o sections within a given segment. The section '__wrapper_sects' |
| 179 | is subdivided according to the index '__wrapper_index' and each sub |
| 180 | sect is named according to the names supplied in '__wrapper_names'. */ |
| 181 | |
| 182 | #define GNU_WRAPPER_SECTS "__wrapper_sects" |
| 183 | #define GNU_WRAPPER_INDEX "__wrapper_index" |
| 184 | #define GNU_WRAPPER_NAMES "__wrapper_names" |
| 185 | |
| 186 | /* Private data for an simple_object_read. */ |
| 187 | |
| 188 | struct simple_object_mach_o_read |
| 189 | { |
| 190 | /* User specified segment name. */ |
| 191 | char *segment_name; |
| 192 | /* Magic number. */ |
| 193 | unsigned int magic; |
| 194 | /* Whether this file is big-endian. */ |
| 195 | int is_big_endian; |
| 196 | /* CPU type from header. */ |
| 197 | unsigned int cputype; |
| 198 | /* CPU subtype from header. */ |
| 199 | unsigned int cpusubtype; |
| 200 | /* Number of commands, from header. */ |
| 201 | unsigned int ncmds; |
| 202 | /* Flags from header. */ |
| 203 | unsigned int flags; |
| 204 | /* Reserved field from header, only used on 64-bit. */ |
| 205 | unsigned int reserved; |
| 206 | }; |
| 207 | |
| 208 | /* Private data for an simple_object_attributes. */ |
| 209 | |
| 210 | struct simple_object_mach_o_attributes |
| 211 | { |
| 212 | /* Magic number. */ |
| 213 | unsigned int magic; |
| 214 | /* Whether this file is big-endian. */ |
| 215 | int is_big_endian; |
| 216 | /* CPU type from header. */ |
| 217 | unsigned int cputype; |
| 218 | /* CPU subtype from header. */ |
| 219 | unsigned int cpusubtype; |
| 220 | /* Flags from header. */ |
| 221 | unsigned int flags; |
| 222 | /* Reserved field from header, only used on 64-bit. */ |
| 223 | unsigned int reserved; |
| 224 | }; |
| 225 | |
| 226 | /* See if we have a Mach-O MH_OBJECT file: |
| 227 | |
| 228 | A standard MH_OBJECT (from as) will have three load commands: |
| 229 | 0 - LC_SEGMENT/LC_SEGMENT64 |
| 230 | 1 - LC_SYMTAB |
| 231 | 2 - LC_DYSYMTAB |
| 232 | |
| 233 | The LC_SEGMENT/LC_SEGMENT64 will introduce a single anonymous segment |
| 234 | containing all the sections. |
| 235 | |
| 236 | Files written by simple-object will have only the segment command |
| 237 | (no symbol tables). */ |
| 238 | |
| 239 | static void * |
| 240 | simple_object_mach_o_match ( |
| 241 | unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN], |
| 242 | int descriptor, |
| 243 | off_t offset, |
| 244 | const char *segment_name, |
| 245 | const char **errmsg, |
| 246 | int *err) |
| 247 | { |
| 248 | unsigned int magic; |
| 249 | int is_big_endian; |
| 250 | unsigned int (*fetch_32) (const unsigned char *); |
| 251 | unsigned int filetype; |
| 252 | struct simple_object_mach_o_read *omr; |
| 253 | unsigned char buf[sizeof (struct mach_o_header_64)]; |
| 254 | unsigned char *b; |
| 255 | |
| 256 | magic = simple_object_fetch_big_32 (header); |
| 257 | if (magic == MACH_O_MH_MAGIC || magic == MACH_O_MH_MAGIC_64) |
| 258 | is_big_endian = 1; |
| 259 | else |
| 260 | { |
| 261 | magic = simple_object_fetch_little_32 (header); |
| 262 | if (magic == MACH_O_MH_MAGIC || magic == MACH_O_MH_MAGIC_64) |
| 263 | is_big_endian = 0; |
| 264 | else |
| 265 | { |
| 266 | *errmsg = NULL; |
| 267 | *err = 0; |
| 268 | return NULL; |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | #ifndef UNSIGNED_64BIT_TYPE |
| 273 | if (magic == MACH_O_MH_MAGIC_64) |
| 274 | { |
| 275 | *errmsg = "64-bit Mach-O objects not supported"; |
| 276 | *err = 0; |
| 277 | return NULL; |
| 278 | } |
| 279 | #endif |
| 280 | |
| 281 | /* We require the user to provide a segment name. This is |
| 282 | unfortunate but I don't see any good choices here. */ |
| 283 | |
| 284 | if (segment_name == NULL) |
| 285 | { |
| 286 | *errmsg = "Mach-O file found but no segment name specified"; |
| 287 | *err = 0; |
| 288 | return NULL; |
| 289 | } |
| 290 | |
| 291 | if (strlen (segment_name) > MACH_O_NAME_LEN) |
| 292 | { |
| 293 | *errmsg = "Mach-O segment name too long"; |
| 294 | *err = 0; |
| 295 | return NULL; |
| 296 | } |
| 297 | |
| 298 | /* The 32-bit and 64-bit headers are similar enough that we can use |
| 299 | the same code. */ |
| 300 | |
| 301 | fetch_32 = (is_big_endian |
| 302 | ? simple_object_fetch_big_32 |
| 303 | : simple_object_fetch_little_32); |
| 304 | |
| 305 | if (!simple_object_internal_read (descriptor, offset, buf, |
| 306 | (magic == MACH_O_MH_MAGIC |
| 307 | ? sizeof (struct mach_o_header_32) |
| 308 | : sizeof (struct mach_o_header_64)), |
| 309 | errmsg, err)) |
| 310 | return NULL; |
| 311 | |
| 312 | b = &buf[0]; |
| 313 | |
| 314 | filetype = (*fetch_32) (b + offsetof (struct mach_o_header_32, filetype)); |
| 315 | if (filetype != MACH_O_MH_OBJECT) |
| 316 | { |
| 317 | *errmsg = "Mach-O file is not object file"; |
| 318 | *err = 0; |
| 319 | return NULL; |
| 320 | } |
| 321 | |
| 322 | omr = XNEW (struct simple_object_mach_o_read); |
| 323 | omr->segment_name = xstrdup (segment_name); |
| 324 | omr->magic = magic; |
| 325 | omr->is_big_endian = is_big_endian; |
| 326 | omr->cputype = (*fetch_32) (b + offsetof (struct mach_o_header_32, cputype)); |
| 327 | omr->cpusubtype = (*fetch_32) (b |
| 328 | + offsetof (struct mach_o_header_32, |
| 329 | cpusubtype)); |
| 330 | omr->ncmds = (*fetch_32) (b + offsetof (struct mach_o_header_32, ncmds)); |
| 331 | omr->flags = (*fetch_32) (b + offsetof (struct mach_o_header_32, flags)); |
| 332 | if (magic == MACH_O_MH_MAGIC) |
| 333 | omr->reserved = 0; |
| 334 | else |
| 335 | omr->reserved = (*fetch_32) (b |
| 336 | + offsetof (struct mach_o_header_64, |
| 337 | reserved)); |
| 338 | |
| 339 | return (void *) omr; |
| 340 | } |
| 341 | |
| 342 | /* Get the file offset and size from a section header. */ |
| 343 | |
| 344 | static void |
| 345 | simple_object_mach_o_section_info (int is_big_endian, int is_32, |
| 346 | const unsigned char *sechdr, off_t *offset, |
| 347 | size_t *size) |
| 348 | { |
| 349 | unsigned int (*fetch_32) (const unsigned char *); |
| 350 | ulong_type (*fetch_64) (const unsigned char *); |
| 351 | |
| 352 | fetch_32 = (is_big_endian |
| 353 | ? simple_object_fetch_big_32 |
| 354 | : simple_object_fetch_little_32); |
| 355 | |
| 356 | fetch_64 = NULL; |
| 357 | #ifdef UNSIGNED_64BIT_TYPE |
| 358 | fetch_64 = (is_big_endian |
| 359 | ? simple_object_fetch_big_64 |
| 360 | : simple_object_fetch_little_64); |
| 361 | #endif |
| 362 | |
| 363 | if (is_32) |
| 364 | { |
| 365 | *offset = fetch_32 (sechdr |
| 366 | + offsetof (struct mach_o_section_32, offset)); |
| 367 | *size = fetch_32 (sechdr |
| 368 | + offsetof (struct mach_o_section_32, size)); |
| 369 | } |
| 370 | else |
| 371 | { |
| 372 | *offset = fetch_32 (sechdr |
| 373 | + offsetof (struct mach_o_section_64, offset)); |
| 374 | *size = fetch_64 (sechdr |
| 375 | + offsetof (struct mach_o_section_64, size)); |
| 376 | } |
| 377 | } |
| 378 | |
| 379 | /* Handle a segment in a Mach-O Object file. |
| 380 | |
| 381 | This will callback to the function pfn for each "section found" the meaning |
| 382 | of which depends on gnu extensions to mach-o: |
| 383 | |
| 384 | If we find mach-o sections (with the segment name as specified) which also |
| 385 | contain: a 'sects' wrapper, an index, and a name table, we expand this into |
| 386 | as many sections as are specified in the index. In this case, there will |
| 387 | be a callback for each of these. |
| 388 | |
| 389 | We will also allow an extension that permits long names (more than 16 |
| 390 | characters) to be used with mach-o. In this case, the section name has |
| 391 | a specific format embedding an index into a name table, and the file must |
| 392 | contain such name table. |
| 393 | |
| 394 | Return 1 if we should continue, 0 if the caller should return. */ |
| 395 | |
| 396 | #define SOMO_SECTS_PRESENT 0x01 |
| 397 | #define SOMO_INDEX_PRESENT 0x02 |
| 398 | #define SOMO_NAMES_PRESENT 0x04 |
| 399 | #define SOMO_LONGN_PRESENT 0x08 |
| 400 | #define SOMO_WRAPPING (SOMO_SECTS_PRESENT | SOMO_INDEX_PRESENT \ |
| 401 | | SOMO_NAMES_PRESENT) |
| 402 | |
| 403 | static int |
| 404 | simple_object_mach_o_segment (simple_object_read *sobj, off_t offset, |
| 405 | const unsigned char *segbuf, |
| 406 | int (*pfn) (void *, const char *, off_t offset, |
| 407 | off_t length), |
| 408 | void *data, |
| 409 | const char **errmsg, int *err) |
| 410 | { |
| 411 | struct simple_object_mach_o_read *omr = |
| 412 | (struct simple_object_mach_o_read *) sobj->data; |
| 413 | unsigned int (*fetch_32) (const unsigned char *); |
| 414 | int is_32; |
| 415 | size_t seghdrsize; |
| 416 | size_t sechdrsize; |
| 417 | size_t segname_offset; |
| 418 | size_t sectname_offset; |
| 419 | unsigned int nsects; |
| 420 | unsigned char *secdata; |
| 421 | unsigned int i; |
| 422 | unsigned int gnu_sections_found; |
| 423 | unsigned int strtab_index; |
| 424 | unsigned int index_index; |
| 425 | unsigned int nametab_index; |
| 426 | unsigned int sections_index; |
| 427 | char *strtab; |
| 428 | char *nametab; |
| 429 | unsigned char *index; |
| 430 | size_t strtab_size; |
| 431 | size_t nametab_size; |
| 432 | size_t index_size; |
| 433 | unsigned int n_wrapped_sects; |
| 434 | size_t wrapper_sect_size; |
| 435 | off_t wrapper_sect_offset = 0; |
| 436 | |
| 437 | fetch_32 = (omr->is_big_endian |
| 438 | ? simple_object_fetch_big_32 |
| 439 | : simple_object_fetch_little_32); |
| 440 | |
| 441 | is_32 = omr->magic == MACH_O_MH_MAGIC; |
| 442 | |
| 443 | if (is_32) |
| 444 | { |
| 445 | seghdrsize = sizeof (struct mach_o_segment_command_32); |
| 446 | sechdrsize = sizeof (struct mach_o_section_32); |
| 447 | segname_offset = offsetof (struct mach_o_section_32, segname); |
| 448 | sectname_offset = offsetof (struct mach_o_section_32, sectname); |
| 449 | nsects = (*fetch_32) (segbuf |
| 450 | + offsetof (struct mach_o_segment_command_32, |
| 451 | nsects)); |
| 452 | } |
| 453 | else |
| 454 | { |
| 455 | seghdrsize = sizeof (struct mach_o_segment_command_64); |
| 456 | sechdrsize = sizeof (struct mach_o_section_64); |
| 457 | segname_offset = offsetof (struct mach_o_section_64, segname); |
| 458 | sectname_offset = offsetof (struct mach_o_section_64, sectname); |
| 459 | nsects = (*fetch_32) (segbuf |
| 460 | + offsetof (struct mach_o_segment_command_64, |
| 461 | nsects)); |
| 462 | } |
| 463 | |
| 464 | /* Fetch the section headers from the segment command. */ |
| 465 | |
| 466 | secdata = XNEWVEC (unsigned char, nsects * sechdrsize); |
| 467 | if (!simple_object_internal_read (sobj->descriptor, offset + seghdrsize, |
| 468 | secdata, nsects * sechdrsize, errmsg, err)) |
| 469 | { |
| 470 | XDELETEVEC (secdata); |
| 471 | return 0; |
| 472 | } |
| 473 | |
| 474 | /* Scan for special sections that signal GNU extensions to the format. */ |
| 475 | |
| 476 | gnu_sections_found = 0; |
| 477 | index_index = nsects; |
| 478 | sections_index = nsects; |
| 479 | strtab_index = nsects; |
| 480 | nametab_index = nsects; |
| 481 | for (i = 0; i < nsects; ++i) |
| 482 | { |
| 483 | size_t nameoff; |
| 484 | |
| 485 | nameoff = i * sechdrsize + segname_offset; |
| 486 | if (strcmp ((char *) secdata + nameoff, omr->segment_name) != 0) |
| 487 | continue; |
| 488 | |
| 489 | nameoff = i * sechdrsize + sectname_offset; |
| 490 | if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_NAMES) == 0) |
| 491 | { |
| 492 | nametab_index = i; |
| 493 | gnu_sections_found |= SOMO_NAMES_PRESENT; |
| 494 | } |
| 495 | else if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_INDEX) == 0) |
| 496 | { |
| 497 | index_index = i; |
| 498 | gnu_sections_found |= SOMO_INDEX_PRESENT; |
| 499 | } |
| 500 | else if (strcmp ((char *) secdata + nameoff, GNU_WRAPPER_SECTS) == 0) |
| 501 | { |
| 502 | sections_index = i; |
| 503 | gnu_sections_found |= SOMO_SECTS_PRESENT; |
| 504 | } |
| 505 | else if (strcmp ((char *) secdata + nameoff, GNU_SECTION_NAMES) == 0) |
| 506 | { |
| 507 | strtab_index = i; |
| 508 | gnu_sections_found |= SOMO_LONGN_PRESENT; |
| 509 | } |
| 510 | } |
| 511 | |
| 512 | /* If any of the special wrapper section components is present, then |
| 513 | they all should be. */ |
| 514 | |
| 515 | if ((gnu_sections_found & SOMO_WRAPPING) != 0) |
| 516 | { |
| 517 | off_t nametab_offset; |
| 518 | off_t index_offset; |
| 519 | |
| 520 | if ((gnu_sections_found & SOMO_WRAPPING) != SOMO_WRAPPING) |
| 521 | { |
| 522 | *errmsg = "GNU Mach-o section wrapper: required section missing"; |
| 523 | *err = 0; /* No useful errno. */ |
| 524 | XDELETEVEC (secdata); |
| 525 | return 0; |
| 526 | } |
| 527 | |
| 528 | /* Fetch the name table. */ |
| 529 | |
| 530 | simple_object_mach_o_section_info (omr->is_big_endian, is_32, |
| 531 | secdata + nametab_index * sechdrsize, |
| 532 | &nametab_offset, &nametab_size); |
| 533 | nametab = XNEWVEC (char, nametab_size); |
| 534 | if (!simple_object_internal_read (sobj->descriptor, |
| 535 | sobj->offset + nametab_offset, |
| 536 | (unsigned char *) nametab, nametab_size, |
| 537 | errmsg, err)) |
| 538 | { |
| 539 | XDELETEVEC (nametab); |
| 540 | XDELETEVEC (secdata); |
| 541 | return 0; |
| 542 | } |
| 543 | |
| 544 | /* Fetch the index. */ |
| 545 | |
| 546 | simple_object_mach_o_section_info (omr->is_big_endian, is_32, |
| 547 | secdata + index_index * sechdrsize, |
| 548 | &index_offset, &index_size); |
| 549 | index = XNEWVEC (unsigned char, index_size); |
| 550 | if (!simple_object_internal_read (sobj->descriptor, |
| 551 | sobj->offset + index_offset, |
| 552 | index, index_size, |
| 553 | errmsg, err)) |
| 554 | { |
| 555 | XDELETEVEC (index); |
| 556 | XDELETEVEC (nametab); |
| 557 | XDELETEVEC (secdata); |
| 558 | return 0; |
| 559 | } |
| 560 | |
| 561 | /* The index contains 4 unsigned ints per sub-section: |
| 562 | sub-section offset/length, sub-section name/length. |
| 563 | We fix this for both 32 and 64 bit mach-o for now, since |
| 564 | other fields limit the maximum size of an object to 4G. */ |
| 565 | n_wrapped_sects = index_size / 16; |
| 566 | |
| 567 | /* Get the parameters for the wrapper too. */ |
| 568 | simple_object_mach_o_section_info (omr->is_big_endian, is_32, |
| 569 | secdata + sections_index * sechdrsize, |
| 570 | &wrapper_sect_offset, |
| 571 | &wrapper_sect_size); |
| 572 | } |
| 573 | else |
| 574 | { |
| 575 | index = NULL; |
| 576 | index_size = 0; |
| 577 | nametab = NULL; |
| 578 | nametab_size = 0; |
| 579 | n_wrapped_sects = 0; |
| 580 | } |
| 581 | |
| 582 | /* If we have a long names section, fetch it. */ |
| 583 | |
| 584 | if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0) |
| 585 | { |
| 586 | off_t strtab_offset; |
| 587 | |
| 588 | simple_object_mach_o_section_info (omr->is_big_endian, is_32, |
| 589 | secdata + strtab_index * sechdrsize, |
| 590 | &strtab_offset, &strtab_size); |
| 591 | strtab = XNEWVEC (char, strtab_size); |
| 592 | if (!simple_object_internal_read (sobj->descriptor, |
| 593 | sobj->offset + strtab_offset, |
| 594 | (unsigned char *) strtab, strtab_size, |
| 595 | errmsg, err)) |
| 596 | { |
| 597 | XDELETEVEC (strtab); |
| 598 | XDELETEVEC (index); |
| 599 | XDELETEVEC (nametab); |
| 600 | XDELETEVEC (secdata); |
| 601 | return 0; |
| 602 | } |
| 603 | } |
| 604 | else |
| 605 | { |
| 606 | strtab = NULL; |
| 607 | strtab_size = 0; |
| 608 | strtab_index = nsects; |
| 609 | } |
| 610 | |
| 611 | /* Process the sections. */ |
| 612 | |
| 613 | for (i = 0; i < nsects; ++i) |
| 614 | { |
| 615 | const unsigned char *sechdr; |
| 616 | char namebuf[MACH_O_NAME_LEN * 2 + 2]; |
| 617 | char *name; |
| 618 | off_t secoffset; |
| 619 | size_t secsize; |
| 620 | int l; |
| 621 | |
| 622 | sechdr = secdata + i * sechdrsize; |
| 623 | |
| 624 | /* We've already processed the long section names. */ |
| 625 | |
| 626 | if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0 |
| 627 | && i == strtab_index) |
| 628 | continue; |
| 629 | |
| 630 | /* We only act on the segment named. */ |
| 631 | |
| 632 | if (strcmp ((char *) sechdr + segname_offset, omr->segment_name) != 0) |
| 633 | continue; |
| 634 | |
| 635 | /* Process sections associated with the wrapper. */ |
| 636 | |
| 637 | if ((gnu_sections_found & SOMO_WRAPPING) != 0) |
| 638 | { |
| 639 | if (i == nametab_index || i == index_index) |
| 640 | continue; |
| 641 | |
| 642 | if (i == sections_index) |
| 643 | { |
| 644 | unsigned int j; |
| 645 | for (j = 0; j < n_wrapped_sects; ++j) |
| 646 | { |
| 647 | unsigned int subsect_offset, subsect_length, name_offset; |
| 648 | subsect_offset = (*fetch_32) (index + 16 * j); |
| 649 | subsect_length = (*fetch_32) (index + 16 * j + 4); |
| 650 | name_offset = (*fetch_32) (index + 16 * j + 8); |
| 651 | /* We don't need the name_length yet. */ |
| 652 | |
| 653 | secoffset = wrapper_sect_offset + subsect_offset; |
| 654 | secsize = subsect_length; |
| 655 | name = nametab + name_offset; |
| 656 | |
| 657 | if (!(*pfn) (data, name, secoffset, secsize)) |
| 658 | { |
| 659 | *errmsg = NULL; |
| 660 | *err = 0; |
| 661 | XDELETEVEC (index); |
| 662 | XDELETEVEC (nametab); |
| 663 | XDELETEVEC (strtab); |
| 664 | XDELETEVEC (secdata); |
| 665 | return 0; |
| 666 | } |
| 667 | } |
| 668 | continue; |
| 669 | } |
| 670 | } |
| 671 | |
| 672 | if ((gnu_sections_found & SOMO_LONGN_PRESENT) != 0) |
| 673 | { |
| 674 | memcpy (namebuf, sechdr + sectname_offset, MACH_O_NAME_LEN); |
| 675 | namebuf[MACH_O_NAME_LEN] = '\0'; |
| 676 | |
| 677 | name = &namebuf[0]; |
| 678 | if (strtab != NULL && name[0] == '_' && name[1] == '_') |
| 679 | { |
| 680 | unsigned long stringoffset; |
| 681 | |
| 682 | if (sscanf (name + 2, "%08lX", &stringoffset) == 1) |
| 683 | { |
| 684 | if (stringoffset >= strtab_size) |
| 685 | { |
| 686 | *errmsg = "section name offset out of range"; |
| 687 | *err = 0; |
| 688 | XDELETEVEC (index); |
| 689 | XDELETEVEC (nametab); |
| 690 | XDELETEVEC (strtab); |
| 691 | XDELETEVEC (secdata); |
| 692 | return 0; |
| 693 | } |
| 694 | |
| 695 | name = strtab + stringoffset; |
| 696 | } |
| 697 | } |
| 698 | } |
| 699 | else |
| 700 | { |
| 701 | /* Otherwise, make a name like __segment,__section as per the |
| 702 | convention in mach-o asm. */ |
| 703 | name = &namebuf[0]; |
| 704 | memcpy (namebuf, (char *) sechdr + segname_offset, MACH_O_NAME_LEN); |
| 705 | namebuf[MACH_O_NAME_LEN] = '\0'; |
| 706 | l = strlen (namebuf); |
| 707 | namebuf[l] = ','; |
| 708 | memcpy (namebuf + l + 1, (char *) sechdr + sectname_offset, |
| 709 | MACH_O_NAME_LEN); |
| 710 | namebuf[l + 1 + MACH_O_NAME_LEN] = '\0'; |
| 711 | } |
| 712 | |
| 713 | simple_object_mach_o_section_info (omr->is_big_endian, is_32, sechdr, |
| 714 | &secoffset, &secsize); |
| 715 | |
| 716 | if (!(*pfn) (data, name, secoffset, secsize)) |
| 717 | { |
| 718 | *errmsg = NULL; |
| 719 | *err = 0; |
| 720 | XDELETEVEC (index); |
| 721 | XDELETEVEC (nametab); |
| 722 | XDELETEVEC (strtab); |
| 723 | XDELETEVEC (secdata); |
| 724 | return 0; |
| 725 | } |
| 726 | } |
| 727 | |
| 728 | XDELETEVEC (index); |
| 729 | XDELETEVEC (nametab); |
| 730 | XDELETEVEC (strtab); |
| 731 | XDELETEVEC (secdata); |
| 732 | |
| 733 | return 1; |
| 734 | } |
| 735 | |
| 736 | /* Find all sections in a Mach-O file. */ |
| 737 | |
| 738 | static const char * |
| 739 | simple_object_mach_o_find_sections (simple_object_read *sobj, |
| 740 | int (*pfn) (void *, const char *, |
| 741 | off_t offset, off_t length), |
| 742 | void *data, |
| 743 | int *err) |
| 744 | { |
| 745 | struct simple_object_mach_o_read *omr = |
| 746 | (struct simple_object_mach_o_read *) sobj->data; |
| 747 | off_t offset; |
| 748 | size_t seghdrsize; |
| 749 | unsigned int (*fetch_32) (const unsigned char *); |
| 750 | const char *errmsg; |
| 751 | unsigned int i; |
| 752 | |
| 753 | if (omr->magic == MACH_O_MH_MAGIC) |
| 754 | { |
| 755 | offset = sizeof (struct mach_o_header_32); |
| 756 | seghdrsize = sizeof (struct mach_o_segment_command_32); |
| 757 | } |
| 758 | else |
| 759 | { |
| 760 | offset = sizeof (struct mach_o_header_64); |
| 761 | seghdrsize = sizeof (struct mach_o_segment_command_64); |
| 762 | } |
| 763 | |
| 764 | fetch_32 = (omr->is_big_endian |
| 765 | ? simple_object_fetch_big_32 |
| 766 | : simple_object_fetch_little_32); |
| 767 | |
| 768 | for (i = 0; i < omr->ncmds; ++i) |
| 769 | { |
| 770 | unsigned char loadbuf[sizeof (struct mach_o_load_command)]; |
| 771 | unsigned int cmd; |
| 772 | unsigned int cmdsize; |
| 773 | |
| 774 | if (!simple_object_internal_read (sobj->descriptor, |
| 775 | sobj->offset + offset, |
| 776 | loadbuf, |
| 777 | sizeof (struct mach_o_load_command), |
| 778 | &errmsg, err)) |
| 779 | return errmsg; |
| 780 | |
| 781 | cmd = (*fetch_32) (loadbuf + offsetof (struct mach_o_load_command, cmd)); |
| 782 | cmdsize = (*fetch_32) (loadbuf |
| 783 | + offsetof (struct mach_o_load_command, cmdsize)); |
| 784 | |
| 785 | if (cmd == MACH_O_LC_SEGMENT || cmd == MACH_O_LC_SEGMENT_64) |
| 786 | { |
| 787 | unsigned char segbuf[sizeof (struct mach_o_segment_command_64)]; |
| 788 | int r; |
| 789 | |
| 790 | if (!simple_object_internal_read (sobj->descriptor, |
| 791 | sobj->offset + offset, |
| 792 | segbuf, seghdrsize, &errmsg, err)) |
| 793 | return errmsg; |
| 794 | |
| 795 | r = simple_object_mach_o_segment (sobj, offset, segbuf, pfn, |
| 796 | data, &errmsg, err); |
| 797 | if (!r) |
| 798 | return errmsg; |
| 799 | } |
| 800 | |
| 801 | offset += cmdsize; |
| 802 | } |
| 803 | |
| 804 | return NULL; |
| 805 | } |
| 806 | |
| 807 | /* Fetch the attributes for an simple_object_read. */ |
| 808 | |
| 809 | static void * |
| 810 | simple_object_mach_o_fetch_attributes (simple_object_read *sobj, |
| 811 | const char **errmsg ATTRIBUTE_UNUSED, |
| 812 | int *err ATTRIBUTE_UNUSED) |
| 813 | { |
| 814 | struct simple_object_mach_o_read *omr = |
| 815 | (struct simple_object_mach_o_read *) sobj->data; |
| 816 | struct simple_object_mach_o_attributes *ret; |
| 817 | |
| 818 | ret = XNEW (struct simple_object_mach_o_attributes); |
| 819 | ret->magic = omr->magic; |
| 820 | ret->is_big_endian = omr->is_big_endian; |
| 821 | ret->cputype = omr->cputype; |
| 822 | ret->cpusubtype = omr->cpusubtype; |
| 823 | ret->flags = omr->flags; |
| 824 | ret->reserved = omr->reserved; |
| 825 | return ret; |
| 826 | } |
| 827 | |
| 828 | /* Release the private data for an simple_object_read. */ |
| 829 | |
| 830 | static void |
| 831 | simple_object_mach_o_release_read (void *data) |
| 832 | { |
| 833 | struct simple_object_mach_o_read *omr = |
| 834 | (struct simple_object_mach_o_read *) data; |
| 835 | |
| 836 | free (omr->segment_name); |
| 837 | XDELETE (omr); |
| 838 | } |
| 839 | |
| 840 | /* Compare two attributes structures. */ |
| 841 | |
| 842 | static const char * |
| 843 | simple_object_mach_o_attributes_merge (void *todata, void *fromdata, int *err) |
| 844 | { |
| 845 | struct simple_object_mach_o_attributes *to = |
| 846 | (struct simple_object_mach_o_attributes *) todata; |
| 847 | struct simple_object_mach_o_attributes *from = |
| 848 | (struct simple_object_mach_o_attributes *) fromdata; |
| 849 | |
| 850 | if (to->magic != from->magic |
| 851 | || to->is_big_endian != from->is_big_endian |
| 852 | || to->cputype != from->cputype) |
| 853 | { |
| 854 | *err = 0; |
| 855 | return "Mach-O object format mismatch"; |
| 856 | } |
| 857 | return NULL; |
| 858 | } |
| 859 | |
| 860 | /* Release the private data for an attributes structure. */ |
| 861 | |
| 862 | static void |
| 863 | simple_object_mach_o_release_attributes (void *data) |
| 864 | { |
| 865 | XDELETE (data); |
| 866 | } |
| 867 | |
| 868 | /* Prepare to write out a file. */ |
| 869 | |
| 870 | static void * |
| 871 | simple_object_mach_o_start_write (void *attributes_data, |
| 872 | const char **errmsg ATTRIBUTE_UNUSED, |
| 873 | int *err ATTRIBUTE_UNUSED) |
| 874 | { |
| 875 | struct simple_object_mach_o_attributes *attrs = |
| 876 | (struct simple_object_mach_o_attributes *) attributes_data; |
| 877 | struct simple_object_mach_o_attributes *ret; |
| 878 | |
| 879 | /* We're just going to record the attributes, but we need to make a |
| 880 | copy because the user may delete them. */ |
| 881 | ret = XNEW (struct simple_object_mach_o_attributes); |
| 882 | *ret = *attrs; |
| 883 | return ret; |
| 884 | } |
| 885 | |
| 886 | /* Write out the header of a Mach-O file. */ |
| 887 | |
| 888 | static int |
| 889 | simple_object_mach_o_write_header (simple_object_write *sobj, int descriptor, |
| 890 | size_t nsects, const char **errmsg, |
| 891 | int *err) |
| 892 | { |
| 893 | struct simple_object_mach_o_attributes *attrs = |
| 894 | (struct simple_object_mach_o_attributes *) sobj->data; |
| 895 | void (*set_32) (unsigned char *, unsigned int); |
| 896 | unsigned char hdrbuf[sizeof (struct mach_o_header_64)]; |
| 897 | unsigned char *hdr; |
| 898 | size_t wrsize; |
| 899 | |
| 900 | set_32 = (attrs->is_big_endian |
| 901 | ? simple_object_set_big_32 |
| 902 | : simple_object_set_little_32); |
| 903 | |
| 904 | memset (hdrbuf, 0, sizeof hdrbuf); |
| 905 | |
| 906 | /* The 32-bit and 64-bit headers start out the same. */ |
| 907 | |
| 908 | hdr = &hdrbuf[0]; |
| 909 | set_32 (hdr + offsetof (struct mach_o_header_32, magic), attrs->magic); |
| 910 | set_32 (hdr + offsetof (struct mach_o_header_32, cputype), attrs->cputype); |
| 911 | set_32 (hdr + offsetof (struct mach_o_header_32, cpusubtype), |
| 912 | attrs->cpusubtype); |
| 913 | set_32 (hdr + offsetof (struct mach_o_header_32, filetype), MACH_O_MH_OBJECT); |
| 914 | set_32 (hdr + offsetof (struct mach_o_header_32, ncmds), 1); |
| 915 | set_32 (hdr + offsetof (struct mach_o_header_32, flags), attrs->flags); |
| 916 | if (attrs->magic == MACH_O_MH_MAGIC) |
| 917 | { |
| 918 | wrsize = sizeof (struct mach_o_header_32); |
| 919 | set_32 (hdr + offsetof (struct mach_o_header_32, sizeofcmds), |
| 920 | (sizeof (struct mach_o_segment_command_32) |
| 921 | + nsects * sizeof (struct mach_o_section_32))); |
| 922 | } |
| 923 | else |
| 924 | { |
| 925 | set_32 (hdr + offsetof (struct mach_o_header_64, sizeofcmds), |
| 926 | (sizeof (struct mach_o_segment_command_64) |
| 927 | + nsects * sizeof (struct mach_o_section_64))); |
| 928 | set_32 (hdr + offsetof (struct mach_o_header_64, reserved), |
| 929 | attrs->reserved); |
| 930 | wrsize = sizeof (struct mach_o_header_64); |
| 931 | } |
| 932 | |
| 933 | return simple_object_internal_write (descriptor, 0, hdrbuf, wrsize, |
| 934 | errmsg, err); |
| 935 | } |
| 936 | |
| 937 | /* Write a Mach-O section header. */ |
| 938 | |
| 939 | static int |
| 940 | simple_object_mach_o_write_section_header (simple_object_write *sobj, |
| 941 | int descriptor, |
| 942 | size_t sechdr_offset, |
| 943 | const char *name, const char *segn, |
| 944 | size_t secaddr, size_t secsize, |
| 945 | size_t offset, unsigned int align, |
| 946 | const char **errmsg, int *err) |
| 947 | { |
| 948 | struct simple_object_mach_o_attributes *attrs = |
| 949 | (struct simple_object_mach_o_attributes *) sobj->data; |
| 950 | void (*set_32) (unsigned char *, unsigned int); |
| 951 | unsigned char hdrbuf[sizeof (struct mach_o_section_64)]; |
| 952 | unsigned char *hdr; |
| 953 | size_t sechdrsize; |
| 954 | |
| 955 | set_32 = (attrs->is_big_endian |
| 956 | ? simple_object_set_big_32 |
| 957 | : simple_object_set_little_32); |
| 958 | |
| 959 | memset (hdrbuf, 0, sizeof hdrbuf); |
| 960 | |
| 961 | hdr = &hdrbuf[0]; |
| 962 | if (attrs->magic == MACH_O_MH_MAGIC) |
| 963 | { |
| 964 | strncpy ((char *) hdr + offsetof (struct mach_o_section_32, sectname), |
| 965 | name, MACH_O_NAME_LEN); |
| 966 | strncpy ((char *) hdr + offsetof (struct mach_o_section_32, segname), |
| 967 | segn, MACH_O_NAME_LEN); |
| 968 | set_32 (hdr + offsetof (struct mach_o_section_32, addr), secaddr); |
| 969 | set_32 (hdr + offsetof (struct mach_o_section_32, size), secsize); |
| 970 | set_32 (hdr + offsetof (struct mach_o_section_32, offset), offset); |
| 971 | set_32 (hdr + offsetof (struct mach_o_section_32, align), align); |
| 972 | /* reloff left as zero. */ |
| 973 | /* nreloc left as zero. */ |
| 974 | set_32 (hdr + offsetof (struct mach_o_section_32, flags), |
| 975 | MACH_O_S_ATTR_DEBUG); |
| 976 | /* reserved1 left as zero. */ |
| 977 | /* reserved2 left as zero. */ |
| 978 | sechdrsize = sizeof (struct mach_o_section_32); |
| 979 | } |
| 980 | else |
| 981 | { |
| 982 | #ifdef UNSIGNED_64BIT_TYPE |
| 983 | void (*set_64) (unsigned char *, ulong_type); |
| 984 | |
| 985 | set_64 = (attrs->is_big_endian |
| 986 | ? simple_object_set_big_64 |
| 987 | : simple_object_set_little_64); |
| 988 | |
| 989 | strncpy ((char *) hdr + offsetof (struct mach_o_section_64, sectname), |
| 990 | name, MACH_O_NAME_LEN); |
| 991 | strncpy ((char *) hdr + offsetof (struct mach_o_section_64, segname), |
| 992 | segn, MACH_O_NAME_LEN); |
| 993 | set_64 (hdr + offsetof (struct mach_o_section_64, addr), secaddr); |
| 994 | set_64 (hdr + offsetof (struct mach_o_section_64, size), secsize); |
| 995 | set_32 (hdr + offsetof (struct mach_o_section_64, offset), offset); |
| 996 | set_32 (hdr + offsetof (struct mach_o_section_64, align), align); |
| 997 | /* reloff left as zero. */ |
| 998 | /* nreloc left as zero. */ |
| 999 | set_32 (hdr + offsetof (struct mach_o_section_64, flags), |
| 1000 | MACH_O_S_ATTR_DEBUG); |
| 1001 | /* reserved1 left as zero. */ |
| 1002 | /* reserved2 left as zero. */ |
| 1003 | /* reserved3 left as zero. */ |
| 1004 | #endif |
| 1005 | sechdrsize = sizeof (struct mach_o_section_64); |
| 1006 | } |
| 1007 | |
| 1008 | return simple_object_internal_write (descriptor, sechdr_offset, hdr, |
| 1009 | sechdrsize, errmsg, err); |
| 1010 | } |
| 1011 | |
| 1012 | /* Write out the single (anonymous) segment containing the sections of a Mach-O |
| 1013 | Object file. |
| 1014 | |
| 1015 | As a GNU extension to mach-o, when the caller specifies a segment name in |
| 1016 | sobj->segment_name, all the sections passed will be output under a single |
| 1017 | mach-o section header. The caller's sections are indexed within this |
| 1018 | 'wrapper' section by a table stored in a second mach-o section. Finally, |
| 1019 | arbitrary length section names are permitted by the extension and these are |
| 1020 | stored in a table in a third mach-o section. |
| 1021 | |
| 1022 | Note that this is only likely to make any sense for the __GNU_LTO segment |
| 1023 | at present. |
| 1024 | |
| 1025 | If the wrapper extension is not in force, we assume that the section name |
| 1026 | is in the form __SEGMENT_NAME,__section_name as per Mach-O asm. */ |
| 1027 | |
| 1028 | static int |
| 1029 | simple_object_mach_o_write_segment (simple_object_write *sobj, int descriptor, |
| 1030 | size_t *nsects, const char **errmsg, |
| 1031 | int *err) |
| 1032 | { |
| 1033 | struct simple_object_mach_o_attributes *attrs = |
| 1034 | (struct simple_object_mach_o_attributes *) sobj->data; |
| 1035 | void (*set_32) (unsigned char *, unsigned int); |
| 1036 | size_t hdrsize; |
| 1037 | size_t seghdrsize; |
| 1038 | size_t sechdrsize; |
| 1039 | size_t cmdsize; |
| 1040 | size_t offset; |
| 1041 | size_t sechdr_offset; |
| 1042 | size_t secaddr; |
| 1043 | unsigned int name_offset; |
| 1044 | simple_object_write_section *section; |
| 1045 | unsigned char hdrbuf[sizeof (struct mach_o_segment_command_64)]; |
| 1046 | unsigned char *hdr; |
| 1047 | size_t nsects_in; |
| 1048 | unsigned int *index; |
| 1049 | char *snames; |
| 1050 | unsigned int sect; |
| 1051 | |
| 1052 | set_32 = (attrs->is_big_endian |
| 1053 | ? simple_object_set_big_32 |
| 1054 | : simple_object_set_little_32); |
| 1055 | |
| 1056 | /* Write out the sections first. */ |
| 1057 | |
| 1058 | if (attrs->magic == MACH_O_MH_MAGIC) |
| 1059 | { |
| 1060 | hdrsize = sizeof (struct mach_o_header_32); |
| 1061 | seghdrsize = sizeof (struct mach_o_segment_command_32); |
| 1062 | sechdrsize = sizeof (struct mach_o_section_32); |
| 1063 | } |
| 1064 | else |
| 1065 | { |
| 1066 | hdrsize = sizeof (struct mach_o_header_64); |
| 1067 | seghdrsize = sizeof (struct mach_o_segment_command_64); |
| 1068 | sechdrsize = sizeof (struct mach_o_section_64); |
| 1069 | } |
| 1070 | |
| 1071 | name_offset = 0; |
| 1072 | *nsects = nsects_in = 0; |
| 1073 | |
| 1074 | /* Count the number of sections we start with. */ |
| 1075 | |
| 1076 | for (section = sobj->sections; section != NULL; section = section->next) |
| 1077 | nsects_in++; |
| 1078 | |
| 1079 | if (sobj->segment_name != NULL) |
| 1080 | { |
| 1081 | /* We will only write 3 sections: wrapped data, index and names. */ |
| 1082 | |
| 1083 | *nsects = 3; |
| 1084 | |
| 1085 | /* The index has four entries per wrapped section: |
| 1086 | Section Offset, length, Name offset, length. |
| 1087 | Where the offsets are based at the start of the wrapper and name |
| 1088 | sections respectively. |
| 1089 | The values are stored as 32 bit int for both 32 and 64 bit mach-o |
| 1090 | since the size of a mach-o MH_OBJECT cannot exceed 4G owing to |
| 1091 | other constraints. */ |
| 1092 | |
| 1093 | index = XNEWVEC (unsigned int, nsects_in * 4); |
| 1094 | |
| 1095 | /* We now need to figure out the size of the names section. This just |
| 1096 | stores the names as null-terminated c strings, packed without any |
| 1097 | alignment padding. */ |
| 1098 | |
| 1099 | for (section = sobj->sections, sect = 0; section != NULL; |
| 1100 | section = section->next, sect++) |
| 1101 | { |
| 1102 | index[sect*4+2] = name_offset; |
| 1103 | index[sect*4+3] = strlen (section->name) + 1; |
| 1104 | name_offset += strlen (section->name) + 1; |
| 1105 | } |
| 1106 | snames = XNEWVEC (char, name_offset); |
| 1107 | } |
| 1108 | else |
| 1109 | { |
| 1110 | *nsects = nsects_in; |
| 1111 | index = NULL; |
| 1112 | snames = NULL; |
| 1113 | } |
| 1114 | |
| 1115 | sechdr_offset = hdrsize + seghdrsize; |
| 1116 | cmdsize = seghdrsize + *nsects * sechdrsize; |
| 1117 | offset = hdrsize + cmdsize; |
| 1118 | secaddr = 0; |
| 1119 | |
| 1120 | for (section = sobj->sections, sect = 0; |
| 1121 | section != NULL; section = section->next, sect++) |
| 1122 | { |
| 1123 | size_t mask; |
| 1124 | size_t new_offset; |
| 1125 | size_t secsize; |
| 1126 | struct simple_object_write_section_buffer *buffer; |
| 1127 | |
| 1128 | mask = (1U << section->align) - 1; |
| 1129 | new_offset = offset + mask; |
| 1130 | new_offset &= ~ mask; |
| 1131 | while (new_offset > offset) |
| 1132 | { |
| 1133 | unsigned char zeroes[16]; |
| 1134 | size_t write; |
| 1135 | |
| 1136 | memset (zeroes, 0, sizeof zeroes); |
| 1137 | write = new_offset - offset; |
| 1138 | if (write > sizeof zeroes) |
| 1139 | write = sizeof zeroes; |
| 1140 | if (!simple_object_internal_write (descriptor, offset, zeroes, write, |
| 1141 | errmsg, err)) |
| 1142 | return 0; |
| 1143 | offset += write; |
| 1144 | } |
| 1145 | |
| 1146 | secsize = 0; |
| 1147 | for (buffer = section->buffers; buffer != NULL; buffer = buffer->next) |
| 1148 | { |
| 1149 | if (!simple_object_internal_write (descriptor, offset + secsize, |
| 1150 | ((const unsigned char *) |
| 1151 | buffer->buffer), |
| 1152 | buffer->size, errmsg, err)) |
| 1153 | return 0; |
| 1154 | secsize += buffer->size; |
| 1155 | } |
| 1156 | |
| 1157 | if (sobj->segment_name != NULL) |
| 1158 | { |
| 1159 | index[sect*4+0] = (unsigned int) offset; |
| 1160 | index[sect*4+1] = secsize; |
| 1161 | /* Stash the section name in our table. */ |
| 1162 | memcpy (snames + index[sect * 4 + 2], section->name, |
| 1163 | index[sect * 4 + 3]); |
| 1164 | } |
| 1165 | else |
| 1166 | { |
| 1167 | char namebuf[MACH_O_NAME_LEN + 1]; |
| 1168 | char segnbuf[MACH_O_NAME_LEN + 1]; |
| 1169 | char *comma; |
| 1170 | |
| 1171 | /* Try to extract segment,section from the input name. */ |
| 1172 | |
| 1173 | memset (namebuf, 0, sizeof namebuf); |
| 1174 | memset (segnbuf, 0, sizeof segnbuf); |
| 1175 | comma = strchr (section->name, ','); |
| 1176 | if (comma != NULL) |
| 1177 | { |
| 1178 | int len = comma - section->name; |
| 1179 | len = len > MACH_O_NAME_LEN ? MACH_O_NAME_LEN : len; |
| 1180 | strncpy (namebuf, section->name, len); |
| 1181 | strncpy (segnbuf, comma + 1, MACH_O_NAME_LEN); |
| 1182 | } |
| 1183 | else /* just try to copy the name, leave segment blank. */ |
| 1184 | strncpy (namebuf, section->name, MACH_O_NAME_LEN); |
| 1185 | |
| 1186 | if (!simple_object_mach_o_write_section_header (sobj, descriptor, |
| 1187 | sechdr_offset, |
| 1188 | namebuf, segnbuf, |
| 1189 | secaddr, secsize, |
| 1190 | offset, |
| 1191 | section->align, |
| 1192 | errmsg, err)) |
| 1193 | return 0; |
| 1194 | sechdr_offset += sechdrsize; |
| 1195 | } |
| 1196 | |
| 1197 | offset += secsize; |
| 1198 | secaddr += secsize; |
| 1199 | } |
| 1200 | |
| 1201 | if (sobj->segment_name != NULL) |
| 1202 | { |
| 1203 | size_t secsize; |
| 1204 | unsigned int i; |
| 1205 | |
| 1206 | /* Write the section header for the wrapper. */ |
| 1207 | /* Account for any initial aligment - which becomes the alignment for this |
| 1208 | created section. */ |
| 1209 | |
| 1210 | secsize = (offset - index[0]); |
| 1211 | if (!simple_object_mach_o_write_section_header (sobj, descriptor, |
| 1212 | sechdr_offset, |
| 1213 | GNU_WRAPPER_SECTS, |
| 1214 | sobj->segment_name, |
| 1215 | 0 /*secaddr*/, |
| 1216 | secsize, index[0], |
| 1217 | sobj->sections->align, |
| 1218 | errmsg, err)) |
| 1219 | return 0; |
| 1220 | |
| 1221 | /* Subtract the wrapper section start from the begining of each sub |
| 1222 | section. */ |
| 1223 | |
| 1224 | for (i = 1; i < nsects_in; ++i) |
| 1225 | index[4 * i] -= index[0]; |
| 1226 | index[0] = 0; |
| 1227 | |
| 1228 | sechdr_offset += sechdrsize; |
| 1229 | |
| 1230 | /* Write out the section names. |
| 1231 | ... the header ... |
| 1232 | name_offset contains the length of the section. It is not aligned. */ |
| 1233 | |
| 1234 | if (!simple_object_mach_o_write_section_header (sobj, descriptor, |
| 1235 | sechdr_offset, |
| 1236 | GNU_WRAPPER_NAMES, |
| 1237 | sobj->segment_name, |
| 1238 | 0 /*secaddr*/, |
| 1239 | name_offset, |
| 1240 | offset, |
| 1241 | 0, errmsg, err)) |
| 1242 | return 0; |
| 1243 | |
| 1244 | /* ... and the content.. */ |
| 1245 | if (!simple_object_internal_write (descriptor, offset, |
| 1246 | (const unsigned char *) snames, |
| 1247 | name_offset, errmsg, err)) |
| 1248 | return 0; |
| 1249 | |
| 1250 | sechdr_offset += sechdrsize; |
| 1251 | secaddr += name_offset; |
| 1252 | offset += name_offset; |
| 1253 | |
| 1254 | /* Now do the index, we'll align this to 4 bytes although the read code |
| 1255 | will handle unaligned. */ |
| 1256 | |
| 1257 | offset += 3; |
| 1258 | offset &= ~0x03; |
| 1259 | if (!simple_object_mach_o_write_section_header (sobj, descriptor, |
| 1260 | sechdr_offset, |
| 1261 | GNU_WRAPPER_INDEX, |
| 1262 | sobj->segment_name, |
| 1263 | 0 /*secaddr*/, |
| 1264 | nsects_in * 16, |
| 1265 | offset, |
| 1266 | 2, errmsg, err)) |
| 1267 | return 0; |
| 1268 | |
| 1269 | /* ... and the content.. */ |
| 1270 | if (!simple_object_internal_write (descriptor, offset, |
| 1271 | (const unsigned char *) index, |
| 1272 | nsects_in*16, errmsg, err)) |
| 1273 | return 0; |
| 1274 | |
| 1275 | XDELETEVEC (index); |
| 1276 | XDELETEVEC (snames); |
| 1277 | } |
| 1278 | |
| 1279 | /* Write out the segment header. */ |
| 1280 | |
| 1281 | memset (hdrbuf, 0, sizeof hdrbuf); |
| 1282 | |
| 1283 | hdr = &hdrbuf[0]; |
| 1284 | if (attrs->magic == MACH_O_MH_MAGIC) |
| 1285 | { |
| 1286 | set_32 (hdr + offsetof (struct mach_o_segment_command_32, cmd), |
| 1287 | MACH_O_LC_SEGMENT); |
| 1288 | set_32 (hdr + offsetof (struct mach_o_segment_command_32, cmdsize), |
| 1289 | cmdsize); |
| 1290 | /* MH_OBJECTS have a single, anonymous, segment - so the segment name |
| 1291 | is left empty. */ |
| 1292 | /* vmaddr left as zero. */ |
| 1293 | /* vmsize left as zero. */ |
| 1294 | set_32 (hdr + offsetof (struct mach_o_segment_command_32, fileoff), |
| 1295 | hdrsize + cmdsize); |
| 1296 | set_32 (hdr + offsetof (struct mach_o_segment_command_32, filesize), |
| 1297 | offset - (hdrsize + cmdsize)); |
| 1298 | /* maxprot left as zero. */ |
| 1299 | /* initprot left as zero. */ |
| 1300 | set_32 (hdr + offsetof (struct mach_o_segment_command_32, nsects), |
| 1301 | *nsects); |
| 1302 | /* flags left as zero. */ |
| 1303 | } |
| 1304 | else |
| 1305 | { |
| 1306 | #ifdef UNSIGNED_64BIT_TYPE |
| 1307 | void (*set_64) (unsigned char *, ulong_type); |
| 1308 | |
| 1309 | set_64 = (attrs->is_big_endian |
| 1310 | ? simple_object_set_big_64 |
| 1311 | : simple_object_set_little_64); |
| 1312 | |
| 1313 | set_32 (hdr + offsetof (struct mach_o_segment_command_64, cmd), |
| 1314 | MACH_O_LC_SEGMENT); |
| 1315 | set_32 (hdr + offsetof (struct mach_o_segment_command_64, cmdsize), |
| 1316 | cmdsize); |
| 1317 | /* MH_OBJECTS have a single, anonymous, segment - so the segment name |
| 1318 | is left empty. */ |
| 1319 | /* vmaddr left as zero. */ |
| 1320 | /* vmsize left as zero. */ |
| 1321 | set_64 (hdr + offsetof (struct mach_o_segment_command_64, fileoff), |
| 1322 | hdrsize + cmdsize); |
| 1323 | set_64 (hdr + offsetof (struct mach_o_segment_command_64, filesize), |
| 1324 | offset - (hdrsize + cmdsize)); |
| 1325 | /* maxprot left as zero. */ |
| 1326 | /* initprot left as zero. */ |
| 1327 | set_32 (hdr + offsetof (struct mach_o_segment_command_64, nsects), |
| 1328 | *nsects); |
| 1329 | /* flags left as zero. */ |
| 1330 | #endif |
| 1331 | } |
| 1332 | |
| 1333 | return simple_object_internal_write (descriptor, hdrsize, hdr, seghdrsize, |
| 1334 | errmsg, err); |
| 1335 | } |
| 1336 | |
| 1337 | /* Write out a complete Mach-O file. */ |
| 1338 | |
| 1339 | static const char * |
| 1340 | simple_object_mach_o_write_to_file (simple_object_write *sobj, int descriptor, |
| 1341 | int *err) |
| 1342 | { |
| 1343 | size_t nsects = 0; |
| 1344 | const char *errmsg; |
| 1345 | |
| 1346 | if (!simple_object_mach_o_write_segment (sobj, descriptor, &nsects, |
| 1347 | &errmsg, err)) |
| 1348 | return errmsg; |
| 1349 | |
| 1350 | if (!simple_object_mach_o_write_header (sobj, descriptor, nsects, |
| 1351 | &errmsg, err)) |
| 1352 | return errmsg; |
| 1353 | |
| 1354 | return NULL; |
| 1355 | } |
| 1356 | |
| 1357 | /* Release the private data for an simple_object_write structure. */ |
| 1358 | |
| 1359 | static void |
| 1360 | simple_object_mach_o_release_write (void *data) |
| 1361 | { |
| 1362 | XDELETE (data); |
| 1363 | } |
| 1364 | |
| 1365 | /* The Mach-O functions. */ |
| 1366 | |
| 1367 | const struct simple_object_functions simple_object_mach_o_functions = |
| 1368 | { |
| 1369 | simple_object_mach_o_match, |
| 1370 | simple_object_mach_o_find_sections, |
| 1371 | simple_object_mach_o_fetch_attributes, |
| 1372 | simple_object_mach_o_release_read, |
| 1373 | simple_object_mach_o_attributes_merge, |
| 1374 | simple_object_mach_o_release_attributes, |
| 1375 | simple_object_mach_o_start_write, |
| 1376 | simple_object_mach_o_write_to_file, |
| 1377 | simple_object_mach_o_release_write, |
| 1378 | NULL |
| 1379 | }; |