| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id$ |
| 4 | * |
| 5 | * Catcrypt data encoding |
| 6 | * |
| 7 | * (c) 2004 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Catacomb. |
| 13 | * |
| 14 | * Catacomb is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU Library General Public License as |
| 16 | * published by the Free Software Foundation; either version 2 of the |
| 17 | * License, or (at your option) any later version. |
| 18 | * |
| 19 | * Catacomb is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU Library General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU Library General Public |
| 25 | * License along with Catacomb; if not, write to the Free |
| 26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Header files ------------------------------------------------------*/ |
| 31 | |
| 32 | #include <errno.h> |
| 33 | #include <stdio.h> |
| 34 | |
| 35 | #include <mLib/alloc.h> |
| 36 | #include <mLib/base64.h> |
| 37 | #include <mLib/dstr.h> |
| 38 | #include <mLib/mdwopt.h> |
| 39 | #include <mLib/report.h> |
| 40 | #include <mLib/sub.h> |
| 41 | |
| 42 | #include "cc.h" |
| 43 | |
| 44 | typedef int encbdryp(const char *, void *); |
| 45 | |
| 46 | /*----- Main code ---------------------------------------------------------*/ |
| 47 | |
| 48 | /* --- Binary --- */ |
| 49 | |
| 50 | static enc *bin_encinit(FILE *fp, const char *msg) |
| 51 | { enc *e = CREATE(enc); return (e); } |
| 52 | static enc *bin_decinit(FILE *fp, encbdryp *func, void *p) |
| 53 | { enc *e = CREATE(enc); return (e); } |
| 54 | |
| 55 | static int bin_read(enc *e, void *p, size_t sz) |
| 56 | { |
| 57 | size_t n; |
| 58 | |
| 59 | if (!sz) return (0); |
| 60 | n = fread(p, 1, sz, e->fp); |
| 61 | if (!n || ferror(e->fp)) return (-1); |
| 62 | return (n); |
| 63 | } |
| 64 | |
| 65 | static int bin_write(enc *e, const void *p, size_t sz) |
| 66 | { if (sz && fwrite(p, 1, sz, e->fp) < sz) return (-1); return (0); } |
| 67 | |
| 68 | static int bin_done(enc *e) { return (0); } |
| 69 | |
| 70 | static void bin_destroy(enc *e) { DESTROY(e); } |
| 71 | |
| 72 | /* --- PEM --- */ |
| 73 | |
| 74 | typedef struct pem_encctx { |
| 75 | enc e; |
| 76 | char *msg; |
| 77 | unsigned f; |
| 78 | base64_ctx b; |
| 79 | dstr d; |
| 80 | size_t n; |
| 81 | #define PEMF_NL 1u |
| 82 | #define PEMF_EOF 2u |
| 83 | } pem_encctx; |
| 84 | |
| 85 | static enc *pem_encinit(FILE *fp, const char *msg) |
| 86 | { |
| 87 | pem_encctx *pe = CREATE(pem_encctx); |
| 88 | base64_init(&pe->b); |
| 89 | fprintf(fp, "-----BEGIN %s-----\n", msg); |
| 90 | pe->msg = xstrdup(msg); |
| 91 | dstr_create(&pe->d); |
| 92 | pe->n = 0; |
| 93 | pe->f = 0; |
| 94 | return (&pe->e); |
| 95 | } |
| 96 | |
| 97 | int checkbdry(const char *b, void *p) { return (!p || strcmp(b, p) == 0); } |
| 98 | |
| 99 | static enc *pem_decinit(FILE *fp, encbdryp *func, void *p) |
| 100 | { |
| 101 | char buf[128]; |
| 102 | int i, d; |
| 103 | pem_encctx *pe; |
| 104 | int ch; |
| 105 | |
| 106 | /* --- Go until I find a newline and `-----' --- */ |
| 107 | |
| 108 | top: |
| 109 | d = 0; |
| 110 | for (;;) { |
| 111 | if ((ch = getc(fp)) == EOF) goto fail; |
| 112 | switch (ch) { |
| 113 | case '\n': d = 0; break; |
| 114 | case '-': if (d >= 0) { d++; if (d == 5) goto banner; }; break; |
| 115 | default: d = -1; break; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | /* --- See what the banner looks like --- */ |
| 120 | |
| 121 | banner: |
| 122 | i = d = 0; |
| 123 | for (;;) { |
| 124 | if ((ch = getc(fp)) == EOF) goto fail; |
| 125 | if (ch == '-') { d++; continue; } |
| 126 | if (ch == '\n') break; |
| 127 | if (i + d + 1 >= sizeof(buf)) goto top; |
| 128 | while (d) { buf[i++] = '-'; d--; } |
| 129 | buf[i++] = ch; |
| 130 | } |
| 131 | buf[i] = 0; |
| 132 | |
| 133 | /* --- Check we have the right framing --- */ |
| 134 | |
| 135 | if (d != 5) goto top; |
| 136 | if (strncmp(buf, "BEGIN ", 6) != 0 || (func && !func(buf + 6, p))) |
| 137 | goto top; |
| 138 | |
| 139 | /* --- Ready --- */ |
| 140 | |
| 141 | pe = CREATE(pem_encctx); |
| 142 | base64_init(&pe->b); |
| 143 | pe->msg = xstrdup(buf + 6); |
| 144 | dstr_create(&pe->d); |
| 145 | pe->n = 0; |
| 146 | pe->f = PEMF_NL; |
| 147 | return (&pe->e); |
| 148 | |
| 149 | /* --- Failed --- */ |
| 150 | |
| 151 | fail: |
| 152 | die(EXIT_FAILURE, "initial encapsulation boundary not found"); |
| 153 | return (0); |
| 154 | } |
| 155 | |
| 156 | #define PEM_CHUNKSZ 4096 |
| 157 | |
| 158 | static int pem_read(enc *e, void *p, size_t sz) |
| 159 | { |
| 160 | pem_encctx *pe = (pem_encctx *)e; |
| 161 | char buf[PEM_CHUNKSZ]; |
| 162 | char *pp = p; |
| 163 | int ch; |
| 164 | size_t n; |
| 165 | int rc = 0; |
| 166 | |
| 167 | for (;;) { |
| 168 | n = pe->d.len - pe->n; |
| 169 | if (n > sz) n = sz; |
| 170 | memcpy(pp, pe->d.buf + pe->n, n); |
| 171 | pe->n += n; |
| 172 | pp += n; |
| 173 | rc += n; |
| 174 | sz -= n; |
| 175 | if (!sz) break; |
| 176 | if (pe->f & PEMF_EOF) return (rc ? rc : -1); |
| 177 | dstr_reset(&pe->d); |
| 178 | n = 0; |
| 179 | for (;;) { |
| 180 | if ((ch = getc(pe->e.fp)) == EOF) return (-1); |
| 181 | if ((pe->f & PEMF_NL) && ch == '-') { |
| 182 | ungetc(ch, pe->e.fp); |
| 183 | pe->f |= PEMF_EOF; |
| 184 | break; |
| 185 | } |
| 186 | if (ch == '\n') { pe->f |= PEMF_NL; continue; } |
| 187 | pe->f &= ~PEMF_NL; |
| 188 | buf[n++] = ch; |
| 189 | if (n >= PEM_CHUNKSZ) break; |
| 190 | } |
| 191 | if (n) |
| 192 | base64_decode(&pe->b, buf, n, &pe->d); |
| 193 | if (pe->f & PEMF_EOF) |
| 194 | base64_decode(&pe->b, 0, 0, &pe->d); |
| 195 | pe->n = 0; |
| 196 | } |
| 197 | return (rc); |
| 198 | } |
| 199 | |
| 200 | static int pem_write(enc *e, const void *p, size_t sz) |
| 201 | { |
| 202 | pem_encctx *pe = (pem_encctx *)e; |
| 203 | const char *pp = p; |
| 204 | size_t n; |
| 205 | |
| 206 | while (sz) { |
| 207 | n = PEM_CHUNKSZ; |
| 208 | if (n > sz) n = sz; |
| 209 | dstr_reset(&pe->d); |
| 210 | base64_encode(&pe->b, pp, n, &pe->d); |
| 211 | if (fwrite(pe->d.buf, 1, pe->d.len, pe->e.fp) < pe->d.len) |
| 212 | return (-1); |
| 213 | pp += n; |
| 214 | sz -= n; |
| 215 | } |
| 216 | return (0); |
| 217 | } |
| 218 | |
| 219 | static int pem_encdone(enc *e) |
| 220 | { |
| 221 | pem_encctx *pe = (pem_encctx *)e; |
| 222 | dstr_reset(&pe->d); |
| 223 | base64_encode(&pe->b, 0, 0, &pe->d); |
| 224 | if (fwrite(pe->d.buf, 1, pe->d.len, pe->e.fp) < pe->d.len) |
| 225 | return (-1); |
| 226 | if (pe->b.lnlen) fputc('\n', pe->e.fp); |
| 227 | fprintf(pe->e.fp, "-----END %s-----\n", pe->msg); |
| 228 | return (0); |
| 229 | } |
| 230 | |
| 231 | static int pem_decdone(enc *e) |
| 232 | { |
| 233 | pem_encctx *pe = (pem_encctx *)e; |
| 234 | char buf[128]; |
| 235 | int i, d; |
| 236 | int ch; |
| 237 | |
| 238 | for (d = 0; d < 5; d++) |
| 239 | if ((ch = getc(pe->e.fp)) != '-') goto fail; |
| 240 | i = d = 0; |
| 241 | for (;;) { |
| 242 | if ((ch = getc(pe->e.fp)) == EOF) goto fail; |
| 243 | if (ch == '-') { d++; continue; } |
| 244 | if (ch == '\n') break; |
| 245 | if (i + d + 1 >= sizeof(buf)) goto fail; |
| 246 | while (d) { buf[i++] = '-'; d--; } |
| 247 | buf[i++] = ch; |
| 248 | } |
| 249 | if (d != 5) goto fail; |
| 250 | buf[i] = 0; |
| 251 | if (strncmp(buf, "END ", 4) != 0 || strcmp(buf + 4, pe->msg) != 0) |
| 252 | goto fail; |
| 253 | return (0); |
| 254 | |
| 255 | fail: |
| 256 | die(EXIT_FAILURE, "final encapsulation boundary not found"); |
| 257 | return (-1); |
| 258 | } |
| 259 | |
| 260 | static void pem_destroy(enc *e) |
| 261 | { |
| 262 | pem_encctx *pe = (pem_encctx *)e; |
| 263 | dstr_destroy(&pe->d); |
| 264 | xfree(pe->msg); |
| 265 | DESTROY(pe); |
| 266 | } |
| 267 | |
| 268 | /* --- Encoder table --- */ |
| 269 | |
| 270 | const encops enctab[] = { |
| 271 | { "binary", "rb", "wb", |
| 272 | bin_encinit, bin_decinit, |
| 273 | bin_read, bin_write, |
| 274 | bin_done, bin_done, |
| 275 | bin_destroy }, |
| 276 | { "pem", "r", "w", |
| 277 | pem_encinit, pem_decinit, |
| 278 | pem_read, pem_write, |
| 279 | pem_encdone, pem_decdone, |
| 280 | pem_destroy }, |
| 281 | { 0 } |
| 282 | }; |
| 283 | |
| 284 | /* --- @getenc@ --- * |
| 285 | * |
| 286 | * Arguments: @const char *enc@ = name of wanted encoding |
| 287 | * |
| 288 | * Returns: Pointer to encoder operations. |
| 289 | * |
| 290 | * Use: Finds a named encoder or decoder. |
| 291 | */ |
| 292 | |
| 293 | const encops *getenc(const char *enc) |
| 294 | { |
| 295 | const encops *eo; |
| 296 | |
| 297 | for (eo = enctab; eo->name; eo++) { |
| 298 | if (strcmp(eo->name, enc) == 0) |
| 299 | goto e_found; |
| 300 | } |
| 301 | die(EXIT_FAILURE, "couldn't find encoding `%s'", enc); |
| 302 | e_found: |
| 303 | return (eo); |
| 304 | } |
| 305 | |
| 306 | /* --- @initenc@ --- * |
| 307 | * |
| 308 | * Arguments: @const encops *eo@ = operations (from @getenc@) |
| 309 | * @FILE *fp@ = file handle to attach |
| 310 | * @const char *msg@ = banner message |
| 311 | * |
| 312 | * Returns: The encoder object. |
| 313 | * |
| 314 | * Use: Initializes an encoder. |
| 315 | */ |
| 316 | |
| 317 | enc *initenc(const encops *eo, FILE *fp, const char *msg) |
| 318 | { |
| 319 | enc *e = eo->initenc(fp, msg); |
| 320 | e->ops = eo; |
| 321 | e->fp = fp; |
| 322 | return (e); |
| 323 | } |
| 324 | |
| 325 | /* --- @initdec@ --- * |
| 326 | * |
| 327 | * Arguments: @const encops *eo@ = operations (from @getenc@) |
| 328 | * @FILE *fp@ = file handle to attach |
| 329 | * @int (*func)(const char *, void *)@ = banner check function |
| 330 | * @void *p@ = argument for @func@ |
| 331 | * |
| 332 | * Returns: The encoder object. |
| 333 | * |
| 334 | * Use: Initializes an encoder. |
| 335 | */ |
| 336 | |
| 337 | enc *initdec(const encops *eo, FILE *fp, |
| 338 | int (*func)(const char *, void *), void *p) |
| 339 | { |
| 340 | enc *e = eo->initdec(fp, func, p); |
| 341 | e->ops = eo; |
| 342 | e->fp = fp; |
| 343 | return (e); |
| 344 | } |
| 345 | |
| 346 | /* --- @freeenc@ --- * |
| 347 | * |
| 348 | * Arguments: @enc *e@ = encoder object |
| 349 | * |
| 350 | * Returns: --- |
| 351 | * |
| 352 | * Use: Frees an encoder object. |
| 353 | */ |
| 354 | |
| 355 | void freeenc(enc *e) { e->ops->destroy(e); } |
| 356 | |
| 357 | /*----- Encoding and decoding commands ------------------------------------*/ |
| 358 | |
| 359 | int cmd_encode(int argc, char *argv[]) |
| 360 | { |
| 361 | const char *of = 0; |
| 362 | FILE *ofp = 0; |
| 363 | FILE *fp = 0; |
| 364 | const char *ef = "binary"; |
| 365 | const char *bd = "MESSAGE"; |
| 366 | int i; |
| 367 | size_t n; |
| 368 | char buf[4096]; |
| 369 | unsigned f = 0; |
| 370 | const encops *eo; |
| 371 | enc *e; |
| 372 | |
| 373 | #define f_bogus 1u |
| 374 | |
| 375 | for (;;) { |
| 376 | static const struct option opt[] = { |
| 377 | { "format", OPTF_ARGREQ, 0, 'f' }, |
| 378 | { "boundary", OPTF_ARGREQ, 0, 'b' }, |
| 379 | { "output", OPTF_ARGREQ, 0, 'o' }, |
| 380 | { 0, 0, 0, 0 } |
| 381 | }; |
| 382 | i = mdwopt(argc, argv, "f:b:o:", opt, 0, 0, 0); |
| 383 | if (i < 0) break; |
| 384 | switch (i) { |
| 385 | case 'f': ef = optarg; break; |
| 386 | case 'b': bd = optarg; break; |
| 387 | case 'o': of = optarg; break; |
| 388 | default: f |= f_bogus; break; |
| 389 | } |
| 390 | } |
| 391 | if (argc - optind > 1 || (f & f_bogus)) |
| 392 | die(EXIT_FAILURE, "Usage: encode [-OPTIONS] [FILE]"); |
| 393 | |
| 394 | if ((eo = getenc(ef)) == 0) |
| 395 | die(EXIT_FAILURE, "encoding `%s' not found", ef); |
| 396 | |
| 397 | if (optind == argc) |
| 398 | fp = stdin; |
| 399 | else if (strcmp(argv[optind], "-") == 0) { |
| 400 | fp = stdin; |
| 401 | optind++; |
| 402 | } else if ((fp = fopen(argv[optind], "rb")) == 0) { |
| 403 | die(EXIT_FAILURE, "couldn't open file `%s': %s", |
| 404 | argv[optind], strerror(errno)); |
| 405 | } else |
| 406 | optind++; |
| 407 | |
| 408 | if (!of || strcmp(of, "-") == 0) |
| 409 | ofp = stdout; |
| 410 | else if ((ofp = fopen(of, eo->wmode)) == 0) { |
| 411 | die(EXIT_FAILURE, "couldn't open file `%s' for output: %s", |
| 412 | ofp, strerror(errno)); |
| 413 | } |
| 414 | |
| 415 | e = initenc(eo, ofp, bd); |
| 416 | |
| 417 | do { |
| 418 | n = fread(buf, 1, sizeof(buf), fp); |
| 419 | if (e->ops->write(e, buf, n)) |
| 420 | die(EXIT_FAILURE, "error writing output: %s", strerror(errno)); |
| 421 | } while (n == sizeof(buf)); |
| 422 | e->ops->encdone(e); |
| 423 | freeenc(e); |
| 424 | return (0); |
| 425 | |
| 426 | #undef f_bogus |
| 427 | } |
| 428 | |
| 429 | int cmd_decode(int argc, char *argv[]) |
| 430 | { |
| 431 | const char *of = 0; |
| 432 | FILE *ofp = 0; |
| 433 | FILE *fp = 0; |
| 434 | const char *ef = "binary"; |
| 435 | const char *bd = 0; |
| 436 | int i; |
| 437 | char buf[4096]; |
| 438 | unsigned f = 0; |
| 439 | const encops *eo; |
| 440 | enc *e; |
| 441 | |
| 442 | #define f_bogus 1u |
| 443 | |
| 444 | for (;;) { |
| 445 | static const struct option opt[] = { |
| 446 | { "format", OPTF_ARGREQ, 0, 'f' }, |
| 447 | { "boundary", OPTF_ARGREQ, 0, 'b' }, |
| 448 | { "output", OPTF_ARGREQ, 0, 'o' }, |
| 449 | { 0, 0, 0, 0 } |
| 450 | }; |
| 451 | i = mdwopt(argc, argv, "f:b:o:", opt, 0, 0, 0); |
| 452 | if (i < 0) break; |
| 453 | switch (i) { |
| 454 | case 'f': ef = optarg; break; |
| 455 | case 'b': bd = optarg; break; |
| 456 | case 'o': of = optarg; break; |
| 457 | default: f |= f_bogus; break; |
| 458 | } |
| 459 | } |
| 460 | if (argc - optind > 1 || (f & f_bogus)) |
| 461 | die(EXIT_FAILURE, "Usage: decode [-OPTIONS] [FILE]"); |
| 462 | |
| 463 | if ((eo = getenc(ef)) == 0) |
| 464 | die(EXIT_FAILURE, "encoding `%s' not found", ef); |
| 465 | |
| 466 | if (optind == argc) |
| 467 | fp = stdin; |
| 468 | else if (strcmp(argv[optind], "-") == 0) { |
| 469 | fp = stdin; |
| 470 | optind++; |
| 471 | } else if ((fp = fopen(argv[optind], eo->rmode)) == 0) { |
| 472 | die(EXIT_FAILURE, "couldn't open file `%s': %s", |
| 473 | argv[optind], strerror(errno)); |
| 474 | } else |
| 475 | optind++; |
| 476 | |
| 477 | if (!of || strcmp(of, "-") == 0) |
| 478 | ofp = stdout; |
| 479 | else if ((ofp = fopen(of, "wb")) == 0) { |
| 480 | die(EXIT_FAILURE, "couldn't open file `%s' for output: %s", |
| 481 | ofp, strerror(errno)); |
| 482 | } |
| 483 | |
| 484 | e = initdec(eo, fp, checkbdry, (/*unconst*/ void *)bd); |
| 485 | |
| 486 | do { |
| 487 | if ((i = e->ops->read(e, buf, sizeof(buf))) < 0) |
| 488 | die(EXIT_FAILURE, "error reading input: %s", strerror(errno)); |
| 489 | if (fwrite(buf, 1, i, ofp) < i) |
| 490 | die(EXIT_FAILURE, "error writing output: %s", strerror(errno)); |
| 491 | } while (i == sizeof(buf)); |
| 492 | e->ops->decdone(e); |
| 493 | freeenc(e); |
| 494 | return (0); |
| 495 | |
| 496 | #undef f_bogus |
| 497 | } |
| 498 | |
| 499 | /*----- That's all, folks -------------------------------------------------*/ |