12de3b87aSKai Wang /*-
22de3b87aSKai Wang * Copyright (c) 2006,2009,2010 Joseph Koshy
32de3b87aSKai Wang * All rights reserved.
42de3b87aSKai Wang *
52de3b87aSKai Wang * Redistribution and use in source and binary forms, with or without
62de3b87aSKai Wang * modification, are permitted provided that the following conditions
72de3b87aSKai Wang * are met:
82de3b87aSKai Wang * 1. Redistributions of source code must retain the above copyright
92de3b87aSKai Wang * notice, this list of conditions and the following disclaimer.
102de3b87aSKai Wang * 2. Redistributions in binary form must reproduce the above copyright
112de3b87aSKai Wang * notice, this list of conditions and the following disclaimer in the
122de3b87aSKai Wang * documentation and/or other materials provided with the distribution.
132de3b87aSKai Wang *
142de3b87aSKai Wang * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS `AS IS' AND
152de3b87aSKai Wang * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
162de3b87aSKai Wang * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
172de3b87aSKai Wang * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
182de3b87aSKai Wang * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
192de3b87aSKai Wang * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
202de3b87aSKai Wang * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
212de3b87aSKai Wang * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
222de3b87aSKai Wang * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
232de3b87aSKai Wang * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
242de3b87aSKai Wang * SUCH DAMAGE.
252de3b87aSKai Wang */
262de3b87aSKai Wang
272de3b87aSKai Wang #include <assert.h>
282de3b87aSKai Wang #include <libelf.h>
292de3b87aSKai Wang #include <stdlib.h>
302de3b87aSKai Wang #include <string.h>
312de3b87aSKai Wang
322de3b87aSKai Wang #include "_libelf.h"
332de3b87aSKai Wang #include "_libelf_ar.h"
342de3b87aSKai Wang
352de3b87aSKai Wang ELFTC_VCSID("$Id: libelf_ar_util.c 3174 2015-03-27 17:13:41Z emaste $");
362de3b87aSKai Wang
37cf781b2eSEd Maste /*
382de3b87aSKai Wang * Convert a string bounded by `start' and `start+sz' (exclusive) to a
392de3b87aSKai Wang * number in the specified base.
402de3b87aSKai Wang */
412de3b87aSKai Wang int
_libelf_ar_get_number(const char * src,size_t sz,unsigned int base,size_t * ret)422de3b87aSKai Wang _libelf_ar_get_number(const char *src, size_t sz, unsigned int base,
432de3b87aSKai Wang size_t *ret)
44cf781b2eSEd Maste {
45cf781b2eSEd Maste size_t r;
462de3b87aSKai Wang unsigned int c, v;
472de3b87aSKai Wang const unsigned char *e, *s;
48cf781b2eSEd Maste
49cf781b2eSEd Maste assert(base <= 10);
502de3b87aSKai Wang
512de3b87aSKai Wang s = (const unsigned char *) src;
522de3b87aSKai Wang e = s + sz;
53cf781b2eSEd Maste
542de3b87aSKai Wang /* skip leading blanks */
552de3b87aSKai Wang for (;s < e && (c = *s) == ' '; s++)
562de3b87aSKai Wang ;
572de3b87aSKai Wang
582de3b87aSKai Wang r = 0L;
592de3b87aSKai Wang for (;s < e; s++) {
602de3b87aSKai Wang if ((c = *s) == ' ')
612de3b87aSKai Wang break;
622de3b87aSKai Wang if (c < '0' || c > '9')
632de3b87aSKai Wang return (0);
642de3b87aSKai Wang v = c - '0';
652de3b87aSKai Wang if (v >= base) /* Illegal digit. */
662de3b87aSKai Wang break;
672de3b87aSKai Wang r *= base;
682de3b87aSKai Wang r += v;
692de3b87aSKai Wang }
702de3b87aSKai Wang
712de3b87aSKai Wang *ret = r;
722de3b87aSKai Wang
732de3b87aSKai Wang return (1);
742de3b87aSKai Wang }
752de3b87aSKai Wang
762de3b87aSKai Wang /*
772de3b87aSKai Wang * Return the translated name for an archive member.
782de3b87aSKai Wang */
792de3b87aSKai Wang char *
_libelf_ar_get_translated_name(const struct ar_hdr * arh,Elf * ar)802de3b87aSKai Wang _libelf_ar_get_translated_name(const struct ar_hdr *arh, Elf *ar)
812de3b87aSKai Wang {
822de3b87aSKai Wang char *s;
832de3b87aSKai Wang unsigned char c;
84cf781b2eSEd Maste size_t len, offset;
85cf781b2eSEd Maste const unsigned char *buf, *p, *q, *r;
862de3b87aSKai Wang const size_t bufsize = sizeof(arh->ar_name);
87cf781b2eSEd Maste
882de3b87aSKai Wang assert(arh != NULL);
892de3b87aSKai Wang assert(ar->e_kind == ELF_K_AR);
902de3b87aSKai Wang assert((const unsigned char *) arh >= ar->e_rawfile &&
912de3b87aSKai Wang (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize);
92cf781b2eSEd Maste
93cf781b2eSEd Maste buf = (const unsigned char *) arh->ar_name;
942de3b87aSKai Wang
95cf781b2eSEd Maste /*
962de3b87aSKai Wang * Check for extended naming.
972de3b87aSKai Wang *
982de3b87aSKai Wang * If the name matches the pattern "^/[0-9]+", it is an
992de3b87aSKai Wang * SVR4-style extended name. If the name matches the pattern
1002de3b87aSKai Wang * "#1/[0-9]+", the entry uses BSD style extended naming.
1012de3b87aSKai Wang */
1022de3b87aSKai Wang if (buf[0] == '/' && (c = buf[1]) >= '0' && c <= '9') {
1032de3b87aSKai Wang /*
1042de3b87aSKai Wang * The value in field ar_name is a decimal offset into
1052de3b87aSKai Wang * the archive string table where the actual name
1062de3b87aSKai Wang * resides.
1072de3b87aSKai Wang */
1082de3b87aSKai Wang if (_libelf_ar_get_number((const char *) (buf + 1),
1092de3b87aSKai Wang bufsize - 1, 10, &offset) == 0) {
110cf781b2eSEd Maste LIBELF_SET_ERROR(ARCHIVE, 0);
111cf781b2eSEd Maste return (NULL);
1122de3b87aSKai Wang }
1132de3b87aSKai Wang
1142de3b87aSKai Wang if (offset > ar->e_u.e_ar.e_rawstrtabsz) {
1152de3b87aSKai Wang LIBELF_SET_ERROR(ARCHIVE, 0);
1162de3b87aSKai Wang return (NULL);
1172de3b87aSKai Wang }
1182de3b87aSKai Wang
1192de3b87aSKai Wang p = q = ar->e_u.e_ar.e_rawstrtab + offset;
1202de3b87aSKai Wang r = ar->e_u.e_ar.e_rawstrtab + ar->e_u.e_ar.e_rawstrtabsz;
1212de3b87aSKai Wang
1222de3b87aSKai Wang for (; p < r && *p != '/'; p++)
1232de3b87aSKai Wang ;
1242de3b87aSKai Wang len = (size_t) (p - q + 1); /* space for the trailing NUL */
1252de3b87aSKai Wang
126cf781b2eSEd Maste if ((s = malloc(len)) == NULL) {
1272de3b87aSKai Wang LIBELF_SET_ERROR(RESOURCE, 0);
1282de3b87aSKai Wang return (NULL);
1292de3b87aSKai Wang }
1302de3b87aSKai Wang
1312de3b87aSKai Wang (void) strncpy(s, (const char *) q, len - 1);
1322de3b87aSKai Wang s[len - 1] = '\0';
133cf781b2eSEd Maste
1342de3b87aSKai Wang return (s);
1352de3b87aSKai Wang } else if (IS_EXTENDED_BSD_NAME(buf)) {
1362de3b87aSKai Wang r = buf + LIBELF_AR_BSD_EXTENDED_NAME_PREFIX_SIZE;
1372de3b87aSKai Wang
1382de3b87aSKai Wang if (_libelf_ar_get_number((const char *) r, bufsize -
1392de3b87aSKai Wang LIBELF_AR_BSD_EXTENDED_NAME_PREFIX_SIZE, 10,
140cf781b2eSEd Maste &len) == 0) {
1412de3b87aSKai Wang LIBELF_SET_ERROR(ARCHIVE, 0);
1422de3b87aSKai Wang return (NULL);
1432de3b87aSKai Wang }
1442de3b87aSKai Wang
1452de3b87aSKai Wang /*
1462de3b87aSKai Wang * Allocate space for the file name plus a
1472de3b87aSKai Wang * trailing NUL.
1482de3b87aSKai Wang */
1492de3b87aSKai Wang if ((s = malloc(len + 1)) == NULL) {
1502de3b87aSKai Wang LIBELF_SET_ERROR(RESOURCE, 0);
1512de3b87aSKai Wang return (NULL);
1522de3b87aSKai Wang }
1532de3b87aSKai Wang
1542de3b87aSKai Wang /*
1552de3b87aSKai Wang * The file name follows the archive header.
1562de3b87aSKai Wang */
1572de3b87aSKai Wang q = (const unsigned char *) (arh + 1);
1582de3b87aSKai Wang
159cf781b2eSEd Maste (void) strncpy(s, (const char *) q, len);
1602de3b87aSKai Wang s[len] = '\0';
161cf781b2eSEd Maste
1622de3b87aSKai Wang return (s);
1632de3b87aSKai Wang }
1642de3b87aSKai Wang
1652de3b87aSKai Wang /*
1662de3b87aSKai Wang * A 'normal' name.
1672de3b87aSKai Wang *
1682de3b87aSKai Wang * Skip back over trailing blanks from the end of the field.
1692de3b87aSKai Wang * In the SVR4 format, a '/' is used as a terminator for
1702de3b87aSKai Wang * non-special names.
1712de3b87aSKai Wang */
1722de3b87aSKai Wang for (q = buf + bufsize - 1; q >= buf && *q == ' '; --q)
1732de3b87aSKai Wang ;
1742de3b87aSKai Wang
1752de3b87aSKai Wang if (q >= buf) {
1762de3b87aSKai Wang if (*q == '/') {
1772de3b87aSKai Wang /*
1782de3b87aSKai Wang * SVR4 style names: ignore the trailing
1792de3b87aSKai Wang * character '/', but only if the name is not
1802de3b87aSKai Wang * one of the special names "/" and "//".
1812de3b87aSKai Wang */
1822de3b87aSKai Wang if (q > buf + 1 ||
1832de3b87aSKai Wang (q == (buf + 1) && *buf != '/'))
1842de3b87aSKai Wang q--;
1852de3b87aSKai Wang }
1862de3b87aSKai Wang
1872de3b87aSKai Wang len = (size_t) (q - buf + 2); /* Space for a trailing NUL. */
1882de3b87aSKai Wang } else {
189cf781b2eSEd Maste /* The buffer only had blanks. */
1902de3b87aSKai Wang buf = (const unsigned char *) "";
1912de3b87aSKai Wang len = 1;
192cf781b2eSEd Maste }
1932de3b87aSKai Wang
1942de3b87aSKai Wang if ((s = malloc(len)) == NULL) {
1952de3b87aSKai Wang LIBELF_SET_ERROR(RESOURCE, 0);
1962de3b87aSKai Wang return (NULL);
1972de3b87aSKai Wang }
1982de3b87aSKai Wang
1992de3b87aSKai Wang (void) strncpy(s, (const char *) buf, len - 1);
2002de3b87aSKai Wang s[len - 1] = '\0';
201cf781b2eSEd Maste
2022de3b87aSKai Wang return (s);
2032de3b87aSKai Wang }
2042de3b87aSKai Wang
2052de3b87aSKai Wang /*
2062de3b87aSKai Wang * Return the raw name for an archive member, inclusive of any
2072de3b87aSKai Wang * formatting characters.
2082de3b87aSKai Wang */
2092de3b87aSKai Wang char *
_libelf_ar_get_raw_name(const struct ar_hdr * arh)2102de3b87aSKai Wang _libelf_ar_get_raw_name(const struct ar_hdr *arh)
2112de3b87aSKai Wang {
2122de3b87aSKai Wang char *rawname;
2132de3b87aSKai Wang const size_t namesz = sizeof(arh->ar_name);
2142de3b87aSKai Wang
2152de3b87aSKai Wang if ((rawname = malloc(namesz + 1)) == NULL) {
2162de3b87aSKai Wang LIBELF_SET_ERROR(RESOURCE, 0);
2172de3b87aSKai Wang return (NULL);
2182de3b87aSKai Wang }
2192de3b87aSKai Wang
2202de3b87aSKai Wang (void) strncpy(rawname, arh->ar_name, namesz);
2212de3b87aSKai Wang rawname[namesz] = '\0';
2222de3b87aSKai Wang return (rawname);
2232de3b87aSKai Wang }
2242de3b87aSKai Wang
2252de3b87aSKai Wang /*
2262de3b87aSKai Wang * Open an 'ar' archive.
2272de3b87aSKai Wang */
2282de3b87aSKai Wang Elf *
_libelf_ar_open(Elf * e,int reporterror)2292de3b87aSKai Wang _libelf_ar_open(Elf *e, int reporterror)
2302de3b87aSKai Wang {
2312de3b87aSKai Wang size_t sz;
2322de3b87aSKai Wang int scanahead;
2332de3b87aSKai Wang struct ar_hdr arh;
2342de3b87aSKai Wang unsigned char *s, *end;
2352de3b87aSKai Wang
236cf781b2eSEd Maste _libelf_init_elf(e, ELF_K_AR);
2372de3b87aSKai Wang
2382de3b87aSKai Wang e->e_u.e_ar.e_nchildren = 0;
2392de3b87aSKai Wang e->e_u.e_ar.e_next = (off_t) -1;
2402de3b87aSKai Wang
2412de3b87aSKai Wang /*
2422de3b87aSKai Wang * Look for special members.
2432de3b87aSKai Wang */
2442de3b87aSKai Wang
2452de3b87aSKai Wang s = e->e_rawfile + SARMAG;
2462de3b87aSKai Wang end = e->e_rawfile + e->e_rawsize;
2472de3b87aSKai Wang
2482de3b87aSKai Wang assert(e->e_rawsize > 0);
2492de3b87aSKai Wang
2502de3b87aSKai Wang /*
2512de3b87aSKai Wang * We use heuristics to determine the flavor of the archive we
2522de3b87aSKai Wang * are examining.
2532de3b87aSKai Wang *
2542de3b87aSKai Wang * SVR4 flavor archives use the name "/ " and "// " for
2552de3b87aSKai Wang * special members.
2562de3b87aSKai Wang *
2572de3b87aSKai Wang * In BSD flavor archives the symbol table, if present, is the
2582de3b87aSKai Wang * first archive with name "__.SYMDEF".
2592de3b87aSKai Wang */
2602de3b87aSKai Wang
2612de3b87aSKai Wang #define READ_AR_HEADER(S, ARH, SZ, END) \
2622de3b87aSKai Wang do { \
2632de3b87aSKai Wang if ((S) + sizeof((ARH)) > (END)) \
2642de3b87aSKai Wang goto error; \
2652de3b87aSKai Wang (void) memcpy(&(ARH), (S), sizeof((ARH))); \
2662de3b87aSKai Wang if ((ARH).ar_fmag[0] != '`' || (ARH).ar_fmag[1] != '\n') \
2672de3b87aSKai Wang goto error; \
2682de3b87aSKai Wang if (_libelf_ar_get_number((char *) (ARH).ar_size, \
2692de3b87aSKai Wang sizeof((ARH).ar_size), 10, &(SZ)) == 0) \
270cf781b2eSEd Maste goto error; \
2712de3b87aSKai Wang } while (0)
2722de3b87aSKai Wang
2732de3b87aSKai Wang READ_AR_HEADER(s, arh, sz, end);
2742de3b87aSKai Wang
2752de3b87aSKai Wang /*
2762de3b87aSKai Wang * Handle special archive members for the SVR4 format.
2772de3b87aSKai Wang */
2782de3b87aSKai Wang if (arh.ar_name[0] == '/') {
2792de3b87aSKai Wang if (sz == 0)
2802de3b87aSKai Wang goto error;
2812de3b87aSKai Wang
282bc5438c5SEd Maste e->e_flags |= LIBELF_F_AR_VARIANT_SVR4;
283bc5438c5SEd Maste
2842de3b87aSKai Wang scanahead = 0;
2852de3b87aSKai Wang
2862de3b87aSKai Wang /*
2872de3b87aSKai Wang * The symbol table (file name "/ ") always comes before the
2882de3b87aSKai Wang * string table (file name "// ").
2892de3b87aSKai Wang */
2902de3b87aSKai Wang if (arh.ar_name[1] == ' ') {
2912de3b87aSKai Wang /* "/ " => symbol table. */
2922de3b87aSKai Wang scanahead = 1; /* The string table to follow. */
2932de3b87aSKai Wang
2942de3b87aSKai Wang s += sizeof(arh);
2952de3b87aSKai Wang e->e_u.e_ar.e_rawsymtab = s;
2962de3b87aSKai Wang e->e_u.e_ar.e_rawsymtabsz = sz;
2972de3b87aSKai Wang
2982de3b87aSKai Wang sz = LIBELF_ADJUST_AR_SIZE(sz);
2992de3b87aSKai Wang s += sz;
3002de3b87aSKai Wang
3012de3b87aSKai Wang } else if (arh.ar_name[1] == '/' && arh.ar_name[2] == ' ') {
3022de3b87aSKai Wang /* "// " => string table for long file names. */
3032de3b87aSKai Wang s += sizeof(arh);
3042de3b87aSKai Wang e->e_u.e_ar.e_rawstrtab = s;
3052de3b87aSKai Wang e->e_u.e_ar.e_rawstrtabsz = sz;
3062de3b87aSKai Wang
3072de3b87aSKai Wang sz = LIBELF_ADJUST_AR_SIZE(sz);
3082de3b87aSKai Wang s += sz;
3092de3b87aSKai Wang }
3102de3b87aSKai Wang
3112de3b87aSKai Wang /*
3122de3b87aSKai Wang * If the string table hasn't been seen yet, look for
3132de3b87aSKai Wang * it in the next member.
3142de3b87aSKai Wang */
3152de3b87aSKai Wang if (scanahead) {
3162de3b87aSKai Wang READ_AR_HEADER(s, arh, sz, end);
3172de3b87aSKai Wang
3182de3b87aSKai Wang /* "// " => string table for long file names. */
3192de3b87aSKai Wang if (arh.ar_name[0] == '/' && arh.ar_name[1] == '/' &&
3202de3b87aSKai Wang arh.ar_name[2] == ' ') {
3212de3b87aSKai Wang
3222de3b87aSKai Wang s += sizeof(arh);
3232de3b87aSKai Wang
3242de3b87aSKai Wang e->e_u.e_ar.e_rawstrtab = s;
3252de3b87aSKai Wang e->e_u.e_ar.e_rawstrtabsz = sz;
3262de3b87aSKai Wang
3272de3b87aSKai Wang sz = LIBELF_ADJUST_AR_SIZE(sz);
3282de3b87aSKai Wang s += sz;
3292de3b87aSKai Wang }
3302de3b87aSKai Wang }
3312de3b87aSKai Wang } else if (strncmp(arh.ar_name, LIBELF_AR_BSD_SYMTAB_NAME,
3322de3b87aSKai Wang sizeof(LIBELF_AR_BSD_SYMTAB_NAME) - 1) == 0) {
3332de3b87aSKai Wang /*
3342de3b87aSKai Wang * BSD style archive symbol table.
3352de3b87aSKai Wang */
3362de3b87aSKai Wang s += sizeof(arh);
3372de3b87aSKai Wang e->e_u.e_ar.e_rawsymtab = s;
3382de3b87aSKai Wang e->e_u.e_ar.e_rawsymtabsz = sz;
3392de3b87aSKai Wang
3402de3b87aSKai Wang sz = LIBELF_ADJUST_AR_SIZE(sz);
3412de3b87aSKai Wang s += sz;
3422de3b87aSKai Wang }
3432de3b87aSKai Wang
3442de3b87aSKai Wang /*
3452de3b87aSKai Wang * Update the 'next' offset, so that a subsequent elf_begin()
3462de3b87aSKai Wang * works as expected.
3472de3b87aSKai Wang */
3482de3b87aSKai Wang e->e_u.e_ar.e_next = (off_t) (s - e->e_rawfile);
3492de3b87aSKai Wang
3502de3b87aSKai Wang return (e);
3512de3b87aSKai Wang
3522de3b87aSKai Wang error:
3532de3b87aSKai Wang if (!reporterror) {
3542de3b87aSKai Wang e->e_kind = ELF_K_NONE;
3552de3b87aSKai Wang return (e);
3562de3b87aSKai Wang }
3572de3b87aSKai Wang
3582de3b87aSKai Wang LIBELF_SET_ERROR(ARCHIVE, 0);
3592de3b87aSKai Wang return (NULL);
3602de3b87aSKai Wang }
3612de3b87aSKai Wang