ucert.c

   1 /*
   2  * Copyright (C) 2018 Daniel Golle <daniel@makrotopia.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 3
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #define _GNU_SOURCE
  15
  16 #include <fcntl.h>
  17 #include <dlfcn.h>
  18 #include <stdio.h>
  19 #include <stdbool.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <getopt.h>
  23 #include <stdint.h>
  24 #include <unistd.h>
  25 #include <inttypes.h>
  26 #include <sys/stat.h>
  27 #include <sys/wait.h>
  28
  29 #include <json-c/json.h>
  30 #include <libubox/blob.h>
  31 #include <libubox/utils.h>
  32 #include <libubox/list.h>
  33 #include <libubox/vlist.h>
  34 #include <libubox/blobmsg_json.h>
  35
  36 #include "usign.h"
  37
  38 #define CERT_BUF_LEN 4096
  39
  40 static enum {
  41         CMD_APPEND,
  42         CMD_DUMP,
  43         CMD_ISSUE,
  44         CMD_REVOKE,
  45         CMD_VERIFY,
  46         CMD_NONE,
  47 } cmd = CMD_NONE;
  48
  49 static bool quiet;
  50 #ifndef UCERT_STRIP_MESSAGES
  51 #define DPRINTF(format, ...) if (!quiet) fprintf(stderr, "%s(%d): " format, __func__, __LINE__, ## __VA_ARGS__)
  52 #else
  53 #define DPRINTF(format, ...)
  54 #endif
  55
  56 /*
  57  * ucert structure
  58  * |               BLOB                    |
  59  * |    SIGNATURE    |       PAYLOAD       |
  60  * |                 |[ BLOBMSG CONTAINER ]|
  61  * |                 |[[T,i,v,e,f,pubkey ]]|
  62  */
  63 enum cert_attr {
  64         CERT_ATTR_SIGNATURE,
  65         CERT_ATTR_PAYLOAD,
  66         CERT_ATTR_MAX
  67 };
  68
  69 static const struct blob_attr_info cert_policy[CERT_ATTR_MAX] = {
  70         [CERT_ATTR_SIGNATURE] = { .type = BLOB_ATTR_BINARY },
  71         [CERT_ATTR_PAYLOAD] = { .type = BLOB_ATTR_NESTED },
  72 };
  73
  74 enum cert_cont_attr {
  75         CERT_CT_ATTR_PAYLOAD,
  76         CERT_CT_ATTR_MAX
  77 };
  78
  79 static const struct blobmsg_policy cert_cont_policy[CERT_CT_ATTR_MAX] = {
  80         [CERT_CT_ATTR_PAYLOAD] = { .name = "ucert", .type = BLOBMSG_TYPE_TABLE },
  81 };
  82
  83 enum cert_payload_attr {
  84         CERT_PL_ATTR_CERTTYPE,
  85         CERT_PL_ATTR_CERTID,
  86         CERT_PL_ATTR_VALIDFROMTIME,
  87         CERT_PL_ATTR_EXPIRETIME,
  88         CERT_PL_ATTR_PUBKEY,
  89         CERT_PL_ATTR_KEY_FINGERPRINT,
  90         CERT_PL_ATTR_MAX
  91 };
  92
  93 enum certtype_id {
  94         CERTTYPE_UNSPEC,
  95         CERTTYPE_AUTH,
  96         CERTTYPE_REVOKE
  97 };
  98
  99 static const struct blobmsg_policy cert_payload_policy[CERT_PL_ATTR_MAX] = {
 100         [CERT_PL_ATTR_CERTTYPE] = { .name = "certtype", .type = BLOBMSG_TYPE_INT32 },
 101         [CERT_PL_ATTR_CERTID] = { .name = "certid", .type = BLOBMSG_TYPE_INT32 },
 102         [CERT_PL_ATTR_VALIDFROMTIME] = { .name = "validfrom", .type = BLOBMSG_TYPE_INT64 },
 103         [CERT_PL_ATTR_EXPIRETIME] = { .name = "expiresat", .type = BLOBMSG_TYPE_INT64 },
 104         [CERT_PL_ATTR_PUBKEY] = { .name = "pubkey", .type = BLOBMSG_TYPE_STRING },
 105         [CERT_PL_ATTR_KEY_FINGERPRINT] = { .name = "fingerprint", .type = BLOBMSG_TYPE_STRING },
 106 };
 107
 108 /* list to store certificate chain at runtime */
 109 struct cert_object {
 110         struct list_head list;
 111         struct blob_attr *cert[CERT_ATTR_MAX];
 112 };
 113
 114 /* write buffer to file */
 115 static int write_file(const char *filename, void *buf, size_t len, bool append) {
 116         FILE *f;
 117         size_t outlen;
 118
 119         f = fopen(filename, append?"a":"w");
 120         if (!f)
 121                 return 1;
 122
 123         outlen = fwrite(buf, 1, len, f);
 124         fclose(f);
 125         return (outlen == len);
 126 }
 127
 128 /* load certfile into list */
 129 static int cert_load(const char *certfile, struct list_head *chain) {
 130         FILE *f;
 131         struct blob_attr *certtb[CERT_ATTR_MAX];
 132         struct blob_attr *bufpt;
 133         struct cert_object *cobj;
 134         char filebuf[CERT_BUF_LEN];
 135         int ret = 0, pret = 0;
 136         int len, pos = 0;
 137
 138         f = fopen(certfile, "r");
 139         if (!f)
 140                 return 1;
 141
 142         len = fread(&filebuf, 1, CERT_BUF_LEN - 1, f);
 143         if (len < 64)
 144                 return 1;
 145
 146         ret = ferror(f) || !feof(f);
 147         fclose(f);
 148         if (ret)
 149                 return 1;
 150
 151         bufpt = (struct blob_attr *)filebuf;
 152         do {
 153                 pret = blob_parse(bufpt, certtb, cert_policy, CERT_ATTR_MAX);
 154                 if (pret <= 0)
 155                         /* no attributes found */
 156                         break;
 157
 158                 if (pos + blob_pad_len(bufpt) > len)
 159                         /* blob exceeds filebuffer */
 160                         break;
 161                 else
 162                         pos += blob_pad_len(bufpt);
 163
 164                 if (!certtb[CERT_ATTR_SIGNATURE])
 165                         /* no signature -> drop */
 166                         break;
 167
 168                 cobj = calloc(1, sizeof(*cobj));
 169                 cobj->cert[CERT_ATTR_SIGNATURE] = blob_memdup(certtb[CERT_ATTR_SIGNATURE]);
 170                 if (certtb[CERT_ATTR_PAYLOAD])
 171                         cobj->cert[CERT_ATTR_PAYLOAD] = blob_memdup(certtb[CERT_ATTR_PAYLOAD]);
 172
 173                 list_add_tail(&cobj->list, chain);
 174                 ret += pret;
 175         /* repeat parsing while there is still enough remaining data in buffer */
 176         } while(len > pos + sizeof(struct blob_attr) && (bufpt = blob_next(bufpt)));
 177
 178         return (ret <= 0);
 179 }
 180
 181 #ifdef UCERT_FULL
 182 /* append signature to certfile */
 183 static int cert_append(const char *certfile, const char *sigfile) {
 184         FILE *fs;
 185         char filebuf[CERT_BUF_LEN];
 186         struct blob_buf sigbuf;
 187         int len;
 188         int ret;
 189
 190         fs = fopen(sigfile, "r");
 191         if (!fs)
 192                 return 1;
 193
 194         len = fread(&filebuf, 1, CERT_BUF_LEN - 1, fs);
 195         ret = ferror(fs) || !feof(fs) || (len < 64);
 196         fclose(fs);
 197         if (ret)
 198                 return 1;
 199
 200         blob_buf_init(&sigbuf, 0);
 201         blob_put(&sigbuf, CERT_ATTR_SIGNATURE, filebuf, len);
 202         ret = write_file(certfile, sigbuf.head, blob_raw_len(sigbuf.head), true);
 203         blob_buf_free(&sigbuf);
 204         return ret;
 205 }
 206 #endif
 207
 208 /* verify the signature of a single chain element */
 209 static int cert_verify_blob(struct blob_attr *cert[CERT_ATTR_MAX],
 210                        const char *pubkeyfile, const char *pubkeydir) {
 211         int i;
 212         char msgfname[256], sigfname[256];
 213         int ret;
 214         char tmpdir[] = "/tmp/ucert-XXXXXX";
 215
 216         if (mkdtemp(tmpdir) == NULL)
 217                 return errno;
 218
 219         snprintf(msgfname, sizeof(msgfname) - 1, "%s/%s", tmpdir, "payload");
 220         snprintf(sigfname, sizeof(sigfname) - 1, "%s/%s", tmpdir, "payload.sig");
 221
 222         for (i = 0; i < CERT_ATTR_MAX; i++) {
 223                 struct blob_attr *v = cert[i];
 224
 225                 if (!v)
 226                         break;
 227
 228                 switch(cert_policy[i].type) {
 229                 case BLOB_ATTR_BINARY:
 230                         write_file(sigfname, blob_data(v), blob_len(v), false);
 231                         break;
 232                 case BLOB_ATTR_NESTED:
 233                         write_file(msgfname, blob_data(v), blob_len(v), false);
 234                         break;
 235                 }
 236         }
 237
 238         ret = usign_v(msgfname, pubkeyfile, pubkeydir, sigfname, quiet);
 239
 240         unlink(msgfname);
 241         unlink(sigfname);
 242         rmdir(tmpdir);
 243
 244         return ret;
 245 }
 246
 247 /* verify cert chain (and message) */
 248 static int chain_verify(const char *msgfile, const char *pubkeyfile,
 249                         const char *pubkeydir, struct list_head *chain) {
 250         struct cert_object *cobj;
 251         struct blob_attr *containertb[CERT_CT_ATTR_MAX];
 252         struct blob_attr *payloadtb[CERT_PL_ATTR_MAX];
 253         char tmpdir[] = "/tmp/ucert-XXXXXX";
 254         char chainedpubkey[256] = {0};
 255         char chainedfp[17] = {0};
 256         char extsigfile[256] = {0};
 257         int ret = 1;
 258         int checkmsg = 0;
 259         struct timeval tv;
 260
 261         if (mkdtemp(tmpdir) == NULL)
 262                 return errno;
 263
 264         if (msgfile)
 265                 checkmsg = -1;
 266
 267         gettimeofday(&tv, NULL);
 268
 269         list_for_each_entry(cobj, chain, list) {
 270                 /* blob has payload, verify that using signature */
 271                 if (cobj->cert[CERT_ATTR_PAYLOAD]) {
 272                         uint64_t validfrom;
 273                         uint64_t expiresat;
 274                         uint32_t certtype;
 275
 276                         ret = cert_verify_blob(cobj->cert, chainedpubkey[0]?chainedpubkey:pubkeyfile, pubkeydir);
 277                         if (ret)
 278                                 goto clean_and_return;
 279
 280                         blobmsg_parse(cert_cont_policy,
 281                                       ARRAY_SIZE(cert_cont_policy),
 282                                       containertb,
 283                                       blob_data(cobj->cert[CERT_ATTR_PAYLOAD]),
 284                                       blob_len(cobj->cert[CERT_ATTR_PAYLOAD]));
 285                         if (!containertb[CERT_CT_ATTR_PAYLOAD]) {
 286                                 ret = 1;
 287                                 DPRINTF("no ucert in signed payload\n");
 288                                 goto clean_and_return;
 289                         }
 290                         blobmsg_parse(cert_payload_policy,
 291                                       ARRAY_SIZE(cert_payload_policy),
 292                                       payloadtb,
 293                                       blobmsg_data(containertb[CERT_CT_ATTR_PAYLOAD]),
 294                                       blobmsg_data_len(containertb[CERT_CT_ATTR_PAYLOAD]));
 295
 296                         if (!payloadtb[CERT_PL_ATTR_CERTTYPE] ||
 297                             !payloadtb[CERT_PL_ATTR_VALIDFROMTIME] ||
 298                             !payloadtb[CERT_PL_ATTR_EXPIRETIME] ||
 299                             !payloadtb[CERT_PL_ATTR_PUBKEY]) {
 300                                 ret = 1;
 301                                 DPRINTF("missing mandatory ucert attributes\n");
 302                                 goto clean_and_return;
 303                         }
 304                         certtype = blobmsg_get_u32(payloadtb[CERT_PL_ATTR_CERTTYPE]);
 305                         validfrom = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_VALIDFROMTIME]);
 306                         expiresat = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_EXPIRETIME]);
 307
 308                         if (certtype != CERTTYPE_AUTH) {
 309                                 ret = 2;
 310                                 DPRINTF("wrong certificate type\n");
 311                                 goto clean_and_return;
 312                         }
 313
 314                         if (tv.tv_sec < validfrom ||
 315                             tv.tv_sec >= expiresat) {
 316                                 ret = 3;
 317                                 DPRINTF("certificate expired\n");
 318                                 goto clean_and_return;
 319                         }
 320
 321                         snprintf(chainedpubkey, sizeof(chainedpubkey) - 1, "%s/%s", tmpdir, "chained-pubkey");
 322                         write_file(chainedpubkey,
 323                                    blobmsg_data(payloadtb[CERT_PL_ATTR_PUBKEY]),
 324                                    blobmsg_data_len(payloadtb[CERT_PL_ATTR_PUBKEY]),
 325                                    false);
 326
 327                         if (usign_f_pubkey(chainedfp, chainedpubkey)) {
 328                                 DPRINTF("cannot get fingerprint for chained key\n");
 329                                 ret = 2;
 330                                 goto clean_and_return;
 331                         }
 332                         if (pubkeydir && _usign_key_is_revoked(chainedfp, pubkeydir)) {
 333                                 DPRINTF("key %s has been revoked!\n", chainedfp);
 334                                 ret = 4;
 335                                 goto clean_and_return;
 336                         }
 337                 } else {
 338                 /* blob doesn't have payload, verify message using signature */
 339                         if (msgfile) {
 340                                 snprintf(extsigfile, sizeof(extsigfile) - 1, "%s/%s", tmpdir, "ext-sig");
 341                                 write_file(extsigfile,
 342                                            blob_data(cobj->cert[CERT_ATTR_SIGNATURE]),
 343                                            blob_len(cobj->cert[CERT_ATTR_SIGNATURE]),
 344                                            false);
 345                                 checkmsg = ret = usign_v(msgfile,
 346                                               chainedpubkey[0]?chainedpubkey:pubkeyfile,
 347                                               pubkeydir, extsigfile, quiet);
 348                                 unlink(extsigfile);
 349                         } else {
 350                                 DPRINTF("stray trailing signature without anything to verify!\n");
 351                                 ret = 1;
 352                         };
 353                 }
 354         }
 355
 356         if (checkmsg == -1)
 357                 DPRINTF("missing signature to verify message!\n");
 358
 359 clean_and_return:
 360         if (chainedpubkey[0])
 361                 unlink(chainedpubkey);
 362         rmdir(tmpdir);
 363         return ret | checkmsg;
 364 }
 365
 366 #ifdef UCERT_FULL
 367 /* dump single chain element to console */
 368 static void cert_dump_blob(struct blob_attr *cert[CERT_ATTR_MAX]) {
 369         int i;
 370
 371         for (i = 0; i < CERT_ATTR_MAX; i++) {
 372                 struct blob_attr *v = cert[i];
 373
 374                 if (!v)
 375                         continue;
 376
 377                 switch(cert_policy[i].type) {
 378                 case BLOB_ATTR_BINARY:
 379                         fprintf(stdout, "signature:\n---\n%s---\n", (char *) blob_data(v));
 380                         break;
 381                 case BLOB_ATTR_NESTED:
 382                         fprintf(stdout, "payload:\n---\n%s\n---\n", blobmsg_format_json_indent(blob_data(v), false, 0));
 383                         break;
 384                 }
 385         }
 386 }
 387
 388 /* dump certfile to console */
 389 static int cert_dump(const char *certfile) {
 390         struct cert_object *cobj;
 391         static LIST_HEAD(certchain);
 392         unsigned int count = 0;
 393
 394         if (cert_load(certfile, &certchain)) {
 395                 DPRINTF("cannot parse cert\n");
 396                 return 1;
 397         }
 398
 399         list_for_each_entry(cobj, &certchain, list) {
 400                 fprintf(stdout, "=== CHAIN ELEMENT %02u ===\n", ++count);
 401                 cert_dump_blob(cobj->cert);
 402         }
 403
 404         return 0;
 405 }
 406
 407 /* issue an auth certificate for pubkey */
 408 static int cert_issue(const char *certfile, const char *pubkeyfile, const char *seckeyfile) {
 409         struct blob_buf certbuf;
 410         struct blob_buf payloadbuf;
 411         struct timeval tv;
 412         int pklen, siglen;
 413         int revoker = 1;
 414         void *c;
 415         FILE *pkf, *sigf;
 416         char pkb[512];
 417         char sigb[512];
 418         char fname[256], sfname[256];
 419         char pkfp[17];
 420         char tmpdir[] = "/tmp/ucert-XXXXXX";
 421
 422         pkf = fopen(pubkeyfile, "r");
 423         if (!pkf)
 424                 return -1;
 425
 426         pklen = fread(pkb, 1, 512, pkf);
 427         pkb[pklen] = '\0';
 428
 429         if (pklen < 32)
 430                 return -1;
 431
 432         fclose(pkf);
 433
 434         if (usign_f_pubkey(pkfp, pubkeyfile))
 435                 return -1;
 436
 437         gettimeofday(&tv, NULL);
 438
 439         if (mkdtemp(tmpdir) == NULL)
 440                 return errno;
 441
 442         while (revoker >= 0) {
 443                 blob_buf_init(&payloadbuf, 0);
 444                 c = blobmsg_open_table(&payloadbuf, "ucert");
 445                 blobmsg_add_u32(&payloadbuf, "certtype", revoker?CERTTYPE_REVOKE:CERTTYPE_AUTH);
 446                 blobmsg_add_u64(&payloadbuf, "validfrom", tv.tv_sec);
 447                 if (!revoker) {
 448                         blobmsg_add_u64(&payloadbuf, "expiresat", tv.tv_sec + 60 * 60 * 24 * 365);
 449                         blobmsg_add_string(&payloadbuf, "pubkey", pkb);
 450                 } else {
 451                         blobmsg_add_string(&payloadbuf, "fingerprint", pkfp);
 452                 }
 453
 454                 blobmsg_close_table(&payloadbuf, c);
 455
 456                 snprintf(fname, sizeof(fname) - 1, "%s/%s", tmpdir, revoker?"revoker":"payload");
 457                 write_file(fname, blob_data(payloadbuf.head), blob_len(payloadbuf.head), false);
 458
 459                 snprintf(sfname, sizeof(sfname) - 1, "%s/%s", tmpdir, revoker?"revoker.sig":"payload.sig");
 460                 if (usign_s(fname, seckeyfile, sfname, quiet))
 461                         return 1;
 462
 463                 sigf = fopen(sfname, "r");
 464                 if (!sigf)
 465                         return 1;
 466
 467                 siglen = fread(sigb, 1, 1024, sigf);
 468                 if (siglen < 1)
 469                         return 1;
 470
 471                 sigb[siglen] = '\0';
 472                 fclose(sigf);
 473
 474                 unlink(fname);
 475                 unlink(sfname);
 476
 477                 blob_buf_init(&certbuf, 0);
 478                 blob_put(&certbuf, CERT_ATTR_SIGNATURE, sigb, siglen);
 479                 blob_put(&certbuf, CERT_ATTR_PAYLOAD, blob_data(payloadbuf.head), blob_len(payloadbuf.head));
 480                 snprintf(fname, sizeof(fname) - 1, "%s%s", certfile, revoker?".revoke":"");
 481                 write_file(fname, certbuf.head, blob_raw_len(certbuf.head), true);
 482                 blob_buf_free(&certbuf);
 483                 blob_buf_free(&payloadbuf);
 484
 485                 revoker--;
 486         }
 487
 488         rmdir(tmpdir);
 489
 490         return 0;
 491 }
 492 #endif
 493
 494 /* process revoker certificate */
 495 static int cert_process_revoker(const char *certfile, const char *pubkeydir) {
 496         static LIST_HEAD(certchain);
 497         struct cert_object *cobj;
 498         struct blob_attr *containertb[CERT_CT_ATTR_MAX];
 499         struct blob_attr *payloadtb[CERT_PL_ATTR_MAX];
 500         struct stat st;
 501         struct timeval tv;
 502         uint64_t validfrom;
 503         uint32_t certtype;
 504         char *fingerprint;
 505         char rfname[512];
 506
 507         int ret;
 508
 509         if (cert_load(certfile, &certchain)) {
 510                 DPRINTF("cannot parse cert\n");
 511                 return 1;
 512         }
 513
 514         gettimeofday(&tv, NULL);
 515
 516         list_for_each_entry(cobj, &certchain, list) {
 517                 if (!cobj->cert[CERT_ATTR_PAYLOAD])
 518                         return 2;
 519
 520                 /* blob has payload, verify that using signature */
 521                 ret = cert_verify_blob(cobj->cert, NULL, pubkeydir);
 522                 if (ret)
 523                         return ret;
 524
 525                 blobmsg_parse(cert_cont_policy,
 526                               ARRAY_SIZE(cert_cont_policy),
 527                               containertb,
 528                               blob_data(cobj->cert[CERT_ATTR_PAYLOAD]),
 529                               blob_len(cobj->cert[CERT_ATTR_PAYLOAD]));
 530                 if (!containertb[CERT_CT_ATTR_PAYLOAD]) {
 531                         DPRINTF("no ucert in signed payload\n");
 532                         return 2;
 533                 }
 534
 535                 blobmsg_parse(cert_payload_policy,
 536                               ARRAY_SIZE(cert_payload_policy),
 537                               payloadtb,
 538                               blobmsg_data(containertb[CERT_CT_ATTR_PAYLOAD]),
 539                               blobmsg_data_len(containertb[CERT_CT_ATTR_PAYLOAD]));
 540
 541                 if (!payloadtb[CERT_PL_ATTR_CERTTYPE] ||
 542                     !payloadtb[CERT_PL_ATTR_VALIDFROMTIME] ||
 543                     !payloadtb[CERT_PL_ATTR_KEY_FINGERPRINT]) {
 544                         DPRINTF("missing mandatory ucert attributes\n");
 545                         return 2;
 546                 }
 547
 548                 certtype = blobmsg_get_u32(payloadtb[CERT_PL_ATTR_CERTTYPE]);
 549                 validfrom = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_VALIDFROMTIME]);
 550                 fingerprint = blobmsg_get_string(payloadtb[CERT_PL_ATTR_KEY_FINGERPRINT]);
 551
 552                 if (certtype != CERTTYPE_REVOKE) {
 553                         DPRINTF("wrong certificate type\n");
 554                         return 2;
 555                 }
 556
 557                 if (tv.tv_sec < validfrom) {
 558                         return 3;
 559                 }
 560
 561                 snprintf(rfname, sizeof(rfname)-1, "%s/%s", pubkeydir, fingerprint);
 562                 /* check if entry in pubkeydir exists */
 563                 if (stat(rfname, &st) == 0) {
 564                         if (_usign_key_is_revoked(fingerprint, pubkeydir)) {
 565                                 DPRINTF("existing revoker deadlink for key %s\n", fingerprint);
 566                                 continue;
 567                         };
 568
 569                         /* remove any other entry */
 570                         if (unlink(rfname))
 571                                 return -1;
 572                 }
 573
 574                 ret = symlink(".revoked.", rfname);
 575                 if (ret)
 576                         return ret;
 577
 578                 DPRINTF("created revoker deadlink for key %s\n", fingerprint);
 579         };
 580
 581         return ret;
 582 }
 583
 584 /* load and verify certfile (and message) */
 585 static int cert_verify(const char *certfile, const char *pubkeyfile, const char *pubkeydir, const char *msgfile) {
 586         static LIST_HEAD(certchain);
 587
 588         if (cert_load(certfile, &certchain)) {
 589                 DPRINTF("cannot parse cert\n");
 590                 return 1;
 591         }
 592
 593         return chain_verify(msgfile, pubkeyfile, pubkeydir, &certchain);
 594 }
 595
 596 /* output help */
 597 static int usage(const char *cmd)
 598 {
 599 #ifndef UCERT_STRIP_MESSAGES
 600         fprintf(stderr,
 601                 "Usage: %s <command> <options>\n"
 602                 "Commands:\n"
 603 #ifdef UCERT_FULL
 604                 "  -A:                  append signature (needs -c and -x)\n"
 605                 "  -D:                  dump (needs -c)\n"
 606                 "  -I:                  issue cert and revoker (needs -c and -p and -s)\n"
 607 #endif /* UCERT_FULL */
 608                 "  -R:                  process revoker certificate (needs -c and -P)\n"
 609                 "  -V:                  verify (needs -c and -p|-P, may have -m)\n"
 610                 "Options:\n"
 611                 "  -c <file>:           certificate file\n"
 612                 "  -m <file>:           message file (verify only)\n"
 613                 "  -p <file>:           public key file\n"
 614                 "  -P <path>:           public key directory (verify only)\n"
 615                 "  -q:                  quiet (do not print verification result, use return code only)\n"
 616 #ifdef UCERT_FULL
 617                 "  -s <file>:           secret key file (issue only)\n"
 618                 "  -x <file>:           signature file (append only)\n"
 619 #endif /* UCERT_FULL */
 620                 "\n",
 621                 cmd);
 622 #endif /* UCERT_STRIP_MESSAGES */
 623         return 1;
 624 }
 625
 626 /* parse command line options and call functions */
 627 int main(int argc, char *argv[]) {
 628         int ch;
 629         const char *msgfile = NULL;
 630         const char *pubkeyfile = NULL;
 631         const char *pubkeydir = NULL;
 632         const char *certfile = NULL;
 633 #ifdef UCERT_FULL
 634         const char *sigfile = NULL;
 635         const char *seckeyfile = NULL;
 636 #endif
 637
 638         quiet = false;
 639         while ((ch = getopt(argc, argv,
 640                 "RVc:m:p:P:q"
 641 #ifdef UCERT_FULL
 642                 "ADIs:x:"
 643 #endif
 644                )) != -1) {
 645                 switch (ch) {
 646 #ifdef UCERT_FULL
 647                 case 'A':
 648                         if (cmd != CMD_NONE)
 649                                 return usage(argv[0]);
 650                         cmd = CMD_APPEND;
 651                         break;
 652                 case 'D':
 653                         if (cmd != CMD_NONE)
 654                                 return usage(argv[0]);
 655                         cmd = CMD_DUMP;
 656                         break;
 657                 case 'I':
 658                         if (cmd != CMD_NONE)
 659                                 return usage(argv[0]);
 660                         cmd = CMD_ISSUE;
 661                         break;
 662 #endif
 663                 case 'R':
 664                         if (cmd != CMD_NONE)
 665                                 return usage(argv[0]);
 666                         cmd = CMD_REVOKE;
 667                         break;
 668                 case 'V':
 669                         if (cmd != CMD_NONE)
 670                                 return usage(argv[0]);
 671                         cmd = CMD_VERIFY;
 672                         break;
 673                 case 'c':
 674                         if (certfile || cmd == CMD_NONE)
 675                                 return usage(argv[0]);
 676                         certfile = optarg;
 677                         break;
 678                 case 'm':
 679                         if (msgfile || cmd != CMD_VERIFY)
 680                                 return usage(argv[0]);
 681                         msgfile = optarg;
 682                         break;
 683                 case 'p':
 684                         if (pubkeyfile || (cmd != CMD_VERIFY && cmd != CMD_ISSUE) || cmd == CMD_NONE)
 685                                 return usage(argv[0]);
 686                         pubkeyfile = optarg;
 687                         break;
 688                 case 'P':
 689                         if (pubkeydir || (cmd != CMD_VERIFY && cmd != CMD_REVOKE) || cmd == CMD_NONE)
 690                                 return usage(argv[0]);
 691                         pubkeydir = optarg;
 692                         break;
 693                 case 'q':
 694                         if (quiet)
 695                                 return usage(argv[0]);
 696                         quiet = true;
 697                         break;
 698 #ifdef UCERT_FULL
 699                 case 's':
 700                         if (seckeyfile || cmd != CMD_ISSUE || cmd == CMD_NONE)
 701                                 return usage(argv[0]);
 702                         seckeyfile = optarg;
 703                         break;
 704                 case 'x':
 705                         if (sigfile || cmd != CMD_APPEND || cmd == CMD_NONE)
 706                                 return usage(argv[0]);
 707                         sigfile = optarg;
 708                         break;
 709 #endif
 710                 default:
 711                         return usage(argv[0]);
 712                 }
 713         }
 714
 715         switch (cmd) {
 716 #ifdef UCERT_FULL
 717         case CMD_APPEND:
 718                 if (certfile && sigfile)
 719                         return cert_append(certfile, sigfile);
 720                 else
 721                         return usage(argv[0]);
 722         case CMD_DUMP:
 723                 if (certfile)
 724                         return cert_dump(certfile);
 725                 else
 726                         return usage(argv[0]);
 727         case CMD_ISSUE:
 728                 if (certfile && pubkeyfile && seckeyfile)
 729                         return cert_issue(certfile, pubkeyfile, seckeyfile);
 730                 else
 731                         return usage(argv[0]);
 732 #endif
 733         case CMD_REVOKE:
 734                 if (certfile && pubkeydir)
 735                         return cert_process_revoker(certfile, pubkeydir);
 736                 else
 737                         return usage(argv[0]);
 738         case CMD_VERIFY:
 739                 if (certfile && (pubkeyfile || pubkeydir))
 740                         return cert_verify(certfile, pubkeyfile, pubkeydir, msgfile);
 741                 else
 742                         return usage(argv[0]);
 743         default:
 744                 return usage(argv[0]);
 745         }
 746
 747         /* unreachable */
 748         return usage(argv[0]);
 749 }