| File: | src/lib/libelf/libelf_ar_util.c |
| Warning: | line 55, column 18 Although the value stored to 'c' is used in the enclosing expression, the value is never actually read from 'c' |
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| 1 | /*- |
| 2 | * Copyright (c) 2006,2009,2010 Joseph Koshy |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS `AS IS' AND |
| 15 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 16 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 17 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 18 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 19 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 20 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 21 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 22 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 23 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 24 | * SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | #include <assert.h> |
| 28 | #include <libelf.h> |
| 29 | #include <stdlib.h> |
| 30 | #include <string.h> |
| 31 | |
| 32 | #include "_libelf.h" |
| 33 | #include "_libelf_ar.h" |
| 34 | |
| 35 | ELFTC_VCSID("$Id: libelf_ar_util.c,v 1.1 2019/02/01 05:27:38 jsg Exp $")__asm__(".ident\t\"" "$Id: libelf_ar_util.c,v 1.1 2019/02/01 05:27:38 jsg Exp $" "\""); |
| 36 | |
| 37 | /* |
| 38 | * Convert a string bounded by `start' and `start+sz' (exclusive) to a |
| 39 | * number in the specified base. |
| 40 | */ |
| 41 | int |
| 42 | _libelf_ar_get_number(const char *src, size_t sz, unsigned int base, |
| 43 | size_t *ret) |
| 44 | { |
| 45 | size_t r; |
| 46 | unsigned int c, v; |
| 47 | const unsigned char *e, *s; |
| 48 | |
| 49 | assert(base <= 10)((base <= 10) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 49, __func__, "base <= 10")); |
| 50 | |
| 51 | s = (const unsigned char *) src; |
| 52 | e = s + sz; |
| 53 | |
| 54 | /* skip leading blanks */ |
| 55 | for (;s < e && (c = *s) == ' '; s++) |
Although the value stored to 'c' is used in the enclosing expression, the value is never actually read from 'c' | |
| 56 | ; |
| 57 | |
| 58 | r = 0L; |
| 59 | for (;s < e; s++) { |
| 60 | if ((c = *s) == ' ') |
| 61 | break; |
| 62 | if (c < '0' || c > '9') |
| 63 | return (0); |
| 64 | v = c - '0'; |
| 65 | if (v >= base) /* Illegal digit. */ |
| 66 | break; |
| 67 | r *= base; |
| 68 | r += v; |
| 69 | } |
| 70 | |
| 71 | *ret = r; |
| 72 | |
| 73 | return (1); |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | * Return the translated name for an archive member. |
| 78 | */ |
| 79 | char * |
| 80 | _libelf_ar_get_translated_name(const struct ar_hdr *arh, Elf *ar) |
| 81 | { |
| 82 | char *s; |
| 83 | unsigned char c; |
| 84 | size_t len, offset; |
| 85 | const unsigned char *buf, *p, *q, *r; |
| 86 | const size_t bufsize = sizeof(arh->ar_name); |
| 87 | |
| 88 | assert(arh != NULL)((arh != ((void *)0)) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 88, __func__, "arh != NULL")); |
| 89 | assert(ar->e_kind == ELF_K_AR)((ar->e_kind == ELF_K_AR) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 89, __func__, "ar->e_kind == ELF_K_AR")); |
| 90 | assert((const unsigned char *) arh >= ar->e_rawfile &&(((const unsigned char *) arh >= ar->e_rawfile && (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize ) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 91, __func__, "(const unsigned char *) arh >= ar->e_rawfile && (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize" )) |
| 91 | (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize)(((const unsigned char *) arh >= ar->e_rawfile && (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize ) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 91, __func__, "(const unsigned char *) arh >= ar->e_rawfile && (const unsigned char *) arh < ar->e_rawfile + ar->e_rawsize" )); |
| 92 | |
| 93 | buf = (const unsigned char *) arh->ar_name; |
| 94 | |
| 95 | /* |
| 96 | * Check for extended naming. |
| 97 | * |
| 98 | * If the name matches the pattern "^/[0-9]+", it is an |
| 99 | * SVR4-style extended name. If the name matches the pattern |
| 100 | * "#1/[0-9]+", the entry uses BSD style extended naming. |
| 101 | */ |
| 102 | if (buf[0] == '/' && (c = buf[1]) >= '0' && c <= '9') { |
| 103 | /* |
| 104 | * The value in field ar_name is a decimal offset into |
| 105 | * the archive string table where the actual name |
| 106 | * resides. |
| 107 | */ |
| 108 | if (_libelf_ar_get_number((const char *) (buf + 1), |
| 109 | bufsize - 1, 10, &offset) == 0) { |
| 110 | LIBELF_SET_ERROR(ARCHIVE, 0)do { (_libelf.libelf_error) = (((ELF_E_ARCHIVE) & 0xFF) | (((0)) << 8)); } while (0); |
| 111 | return (NULL((void *)0)); |
| 112 | } |
| 113 | |
| 114 | if (offset > ar->e_u.e_ar.e_rawstrtabsz) { |
| 115 | LIBELF_SET_ERROR(ARCHIVE, 0)do { (_libelf.libelf_error) = (((ELF_E_ARCHIVE) & 0xFF) | (((0)) << 8)); } while (0); |
| 116 | return (NULL((void *)0)); |
| 117 | } |
| 118 | |
| 119 | p = q = ar->e_u.e_ar.e_rawstrtab + offset; |
| 120 | r = ar->e_u.e_ar.e_rawstrtab + ar->e_u.e_ar.e_rawstrtabsz; |
| 121 | |
| 122 | for (; p < r && *p != '/'; p++) |
| 123 | ; |
| 124 | len = (size_t) (p - q + 1); /* space for the trailing NUL */ |
| 125 | |
| 126 | if ((s = malloc(len)) == NULL((void *)0)) { |
| 127 | LIBELF_SET_ERROR(RESOURCE, 0)do { (_libelf.libelf_error) = (((ELF_E_RESOURCE) & 0xFF) | (((0)) << 8)); } while (0); |
| 128 | return (NULL((void *)0)); |
| 129 | } |
| 130 | |
| 131 | (void) strncpy(s, (const char *) q, len - 1); |
| 132 | s[len - 1] = '\0'; |
| 133 | |
| 134 | return (s); |
| 135 | } else if (IS_EXTENDED_BSD_NAME(buf)(strncmp((const char *) (buf), "#1/", (sizeof("#1/") - 1)) == 0)) { |
| 136 | r = buf + LIBELF_AR_BSD_EXTENDED_NAME_PREFIX_SIZE(sizeof("#1/") - 1); |
| 137 | |
| 138 | if (_libelf_ar_get_number((const char *) r, bufsize - |
| 139 | LIBELF_AR_BSD_EXTENDED_NAME_PREFIX_SIZE(sizeof("#1/") - 1), 10, |
| 140 | &len) == 0) { |
| 141 | LIBELF_SET_ERROR(ARCHIVE, 0)do { (_libelf.libelf_error) = (((ELF_E_ARCHIVE) & 0xFF) | (((0)) << 8)); } while (0); |
| 142 | return (NULL((void *)0)); |
| 143 | } |
| 144 | |
| 145 | /* |
| 146 | * Allocate space for the file name plus a |
| 147 | * trailing NUL. |
| 148 | */ |
| 149 | if ((s = malloc(len + 1)) == NULL((void *)0)) { |
| 150 | LIBELF_SET_ERROR(RESOURCE, 0)do { (_libelf.libelf_error) = (((ELF_E_RESOURCE) & 0xFF) | (((0)) << 8)); } while (0); |
| 151 | return (NULL((void *)0)); |
| 152 | } |
| 153 | |
| 154 | /* |
| 155 | * The file name follows the archive header. |
| 156 | */ |
| 157 | q = (const unsigned char *) (arh + 1); |
| 158 | |
| 159 | (void) strncpy(s, (const char *) q, len); |
| 160 | s[len] = '\0'; |
| 161 | |
| 162 | return (s); |
| 163 | } |
| 164 | |
| 165 | /* |
| 166 | * A 'normal' name. |
| 167 | * |
| 168 | * Skip back over trailing blanks from the end of the field. |
| 169 | * In the SVR4 format, a '/' is used as a terminator for |
| 170 | * non-special names. |
| 171 | */ |
| 172 | for (q = buf + bufsize - 1; q >= buf && *q == ' '; --q) |
| 173 | ; |
| 174 | |
| 175 | if (q >= buf) { |
| 176 | if (*q == '/') { |
| 177 | /* |
| 178 | * SVR4 style names: ignore the trailing |
| 179 | * character '/', but only if the name is not |
| 180 | * one of the special names "/" and "//". |
| 181 | */ |
| 182 | if (q > buf + 1 || |
| 183 | (q == (buf + 1) && *buf != '/')) |
| 184 | q--; |
| 185 | } |
| 186 | |
| 187 | len = (size_t) (q - buf + 2); /* Space for a trailing NUL. */ |
| 188 | } else { |
| 189 | /* The buffer only had blanks. */ |
| 190 | buf = (const unsigned char *) ""; |
| 191 | len = 1; |
| 192 | } |
| 193 | |
| 194 | if ((s = malloc(len)) == NULL((void *)0)) { |
| 195 | LIBELF_SET_ERROR(RESOURCE, 0)do { (_libelf.libelf_error) = (((ELF_E_RESOURCE) & 0xFF) | (((0)) << 8)); } while (0); |
| 196 | return (NULL((void *)0)); |
| 197 | } |
| 198 | |
| 199 | (void) strncpy(s, (const char *) buf, len - 1); |
| 200 | s[len - 1] = '\0'; |
| 201 | |
| 202 | return (s); |
| 203 | } |
| 204 | |
| 205 | /* |
| 206 | * Return the raw name for an archive member, inclusive of any |
| 207 | * formatting characters. |
| 208 | */ |
| 209 | char * |
| 210 | _libelf_ar_get_raw_name(const struct ar_hdr *arh) |
| 211 | { |
| 212 | char *rawname; |
| 213 | const size_t namesz = sizeof(arh->ar_name); |
| 214 | |
| 215 | if ((rawname = malloc(namesz + 1)) == NULL((void *)0)) { |
| 216 | LIBELF_SET_ERROR(RESOURCE, 0)do { (_libelf.libelf_error) = (((ELF_E_RESOURCE) & 0xFF) | (((0)) << 8)); } while (0); |
| 217 | return (NULL((void *)0)); |
| 218 | } |
| 219 | |
| 220 | (void) strncpy(rawname, arh->ar_name, namesz); |
| 221 | rawname[namesz] = '\0'; |
| 222 | return (rawname); |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * Open an 'ar' archive. |
| 227 | */ |
| 228 | Elf * |
| 229 | _libelf_ar_open(Elf *e, int reporterror) |
| 230 | { |
| 231 | size_t sz; |
| 232 | int scanahead; |
| 233 | struct ar_hdr arh; |
| 234 | unsigned char *s, *end; |
| 235 | |
| 236 | _libelf_init_elf(e, ELF_K_AR); |
| 237 | |
| 238 | e->e_u.e_ar.e_nchildren = 0; |
| 239 | e->e_u.e_ar.e_next = (off_t) -1; |
| 240 | |
| 241 | /* |
| 242 | * Look for special members. |
| 243 | */ |
| 244 | |
| 245 | s = e->e_rawfile + SARMAG8; |
| 246 | end = e->e_rawfile + e->e_rawsize; |
| 247 | |
| 248 | assert(e->e_rawsize > 0)((e->e_rawsize > 0) ? (void)0 : __assert2("/usr/src/lib/libelf/libelf_ar_util.c" , 248, __func__, "e->e_rawsize > 0")); |
| 249 | |
| 250 | /* |
| 251 | * We use heuristics to determine the flavor of the archive we |
| 252 | * are examining. |
| 253 | * |
| 254 | * SVR4 flavor archives use the name "/ " and "// " for |
| 255 | * special members. |
| 256 | * |
| 257 | * In BSD flavor archives the symbol table, if present, is the |
| 258 | * first archive with name "__.SYMDEF". |
| 259 | */ |
| 260 | |
| 261 | #define READ_AR_HEADER(S, ARH, SZ, END)do { if ((S) + sizeof((ARH)) > (END)) goto error; (void) memcpy (&(ARH), (S), sizeof((ARH))); if ((ARH).ar_fmag[0] != '`' || (ARH).ar_fmag[1] != '\n') goto error; if (_libelf_ar_get_number ((char *) (ARH).ar_size, sizeof((ARH).ar_size), 10, &(SZ) ) == 0) goto error; } while (0) \ |
| 262 | do { \ |
| 263 | if ((S) + sizeof((ARH)) > (END)) \ |
| 264 | goto error; \ |
| 265 | (void) memcpy(&(ARH), (S), sizeof((ARH))); \ |
| 266 | if ((ARH).ar_fmag[0] != '`' || (ARH).ar_fmag[1] != '\n') \ |
| 267 | goto error; \ |
| 268 | if (_libelf_ar_get_number((char *) (ARH).ar_size, \ |
| 269 | sizeof((ARH).ar_size), 10, &(SZ)) == 0) \ |
| 270 | goto error; \ |
| 271 | } while (0) |
| 272 | |
| 273 | READ_AR_HEADER(s, arh, sz, end)do { if ((s) + sizeof((arh)) > (end)) goto error; (void) memcpy (&(arh), (s), sizeof((arh))); if ((arh).ar_fmag[0] != '`' || (arh).ar_fmag[1] != '\n') goto error; if (_libelf_ar_get_number ((char *) (arh).ar_size, sizeof((arh).ar_size), 10, &(sz) ) == 0) goto error; } while (0); |
| 274 | |
| 275 | /* |
| 276 | * Handle special archive members for the SVR4 format. |
| 277 | */ |
| 278 | if (arh.ar_name[0] == '/') { |
| 279 | if (sz == 0) |
| 280 | goto error; |
| 281 | |
| 282 | e->e_flags |= LIBELF_F_AR_VARIANT_SVR40x020000U; |
| 283 | |
| 284 | scanahead = 0; |
| 285 | |
| 286 | /* |
| 287 | * The symbol table (file name "/ ") always comes before the |
| 288 | * string table (file name "// "). |
| 289 | */ |
| 290 | if (arh.ar_name[1] == ' ') { |
| 291 | /* "/ " => symbol table. */ |
| 292 | scanahead = 1; /* The string table to follow. */ |
| 293 | |
| 294 | s += sizeof(arh); |
| 295 | e->e_u.e_ar.e_rawsymtab = s; |
| 296 | e->e_u.e_ar.e_rawsymtabsz = sz; |
| 297 | |
| 298 | sz = LIBELF_ADJUST_AR_SIZE(sz)(((sz) + 1U) & ~1U); |
| 299 | s += sz; |
| 300 | |
| 301 | } else if (arh.ar_name[1] == '/' && arh.ar_name[2] == ' ') { |
| 302 | /* "// " => string table for long file names. */ |
| 303 | s += sizeof(arh); |
| 304 | e->e_u.e_ar.e_rawstrtab = s; |
| 305 | e->e_u.e_ar.e_rawstrtabsz = sz; |
| 306 | |
| 307 | sz = LIBELF_ADJUST_AR_SIZE(sz)(((sz) + 1U) & ~1U); |
| 308 | s += sz; |
| 309 | } |
| 310 | |
| 311 | /* |
| 312 | * If the string table hasn't been seen yet, look for |
| 313 | * it in the next member. |
| 314 | */ |
| 315 | if (scanahead) { |
| 316 | READ_AR_HEADER(s, arh, sz, end)do { if ((s) + sizeof((arh)) > (end)) goto error; (void) memcpy (&(arh), (s), sizeof((arh))); if ((arh).ar_fmag[0] != '`' || (arh).ar_fmag[1] != '\n') goto error; if (_libelf_ar_get_number ((char *) (arh).ar_size, sizeof((arh).ar_size), 10, &(sz) ) == 0) goto error; } while (0); |
| 317 | |
| 318 | /* "// " => string table for long file names. */ |
| 319 | if (arh.ar_name[0] == '/' && arh.ar_name[1] == '/' && |
| 320 | arh.ar_name[2] == ' ') { |
| 321 | |
| 322 | s += sizeof(arh); |
| 323 | |
| 324 | e->e_u.e_ar.e_rawstrtab = s; |
| 325 | e->e_u.e_ar.e_rawstrtabsz = sz; |
| 326 | |
| 327 | sz = LIBELF_ADJUST_AR_SIZE(sz)(((sz) + 1U) & ~1U); |
| 328 | s += sz; |
| 329 | } |
| 330 | } |
| 331 | } else if (strncmp(arh.ar_name, LIBELF_AR_BSD_SYMTAB_NAME"__.SYMDEF", |
| 332 | sizeof(LIBELF_AR_BSD_SYMTAB_NAME"__.SYMDEF") - 1) == 0) { |
| 333 | /* |
| 334 | * BSD style archive symbol table. |
| 335 | */ |
| 336 | s += sizeof(arh); |
| 337 | e->e_u.e_ar.e_rawsymtab = s; |
| 338 | e->e_u.e_ar.e_rawsymtabsz = sz; |
| 339 | |
| 340 | sz = LIBELF_ADJUST_AR_SIZE(sz)(((sz) + 1U) & ~1U); |
| 341 | s += sz; |
| 342 | } |
| 343 | |
| 344 | /* |
| 345 | * Update the 'next' offset, so that a subsequent elf_begin() |
| 346 | * works as expected. |
| 347 | */ |
| 348 | e->e_u.e_ar.e_next = (off_t) (s - e->e_rawfile); |
| 349 | |
| 350 | return (e); |
| 351 | |
| 352 | error: |
| 353 | if (!reporterror) { |
| 354 | e->e_kind = ELF_K_NONE; |
| 355 | return (e); |
| 356 | } |
| 357 | |
| 358 | LIBELF_SET_ERROR(ARCHIVE, 0)do { (_libelf.libelf_error) = (((ELF_E_ARCHIVE) & 0xFF) | (((0)) << 8)); } while (0); |
| 359 | return (NULL((void *)0)); |
| 360 | } |