apps/asn1pars.c

   1 /*
   2  * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include "apps.h"
  14 #include <openssl/err.h>
  15 #include <openssl/evp.h>
  16 #include <openssl/x509.h>
  17 #include <openssl/pem.h>
  18 #include <openssl/asn1t.h>
  19
  20 typedef enum OPTION_choice {
  21     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  22     OPT_INFORM, OPT_IN, OPT_OUT, OPT_INDENT, OPT_NOOUT,
  23     OPT_OID, OPT_OFFSET, OPT_LENGTH, OPT_DUMP, OPT_DLIMIT,
  24     OPT_STRPARSE, OPT_GENSTR, OPT_GENCONF, OPT_STRICTPEM,
  25     OPT_ITEM
  26 } OPTION_CHOICE;
  27
  28 const OPTIONS asn1parse_options[] = {
  29     {"help", OPT_HELP, '-', "Display this summary"},
  30     {"inform", OPT_INFORM, 'F', "input format - one of DER PEM"},
  31     {"in", OPT_IN, '<', "input file"},
  32     {"out", OPT_OUT, '>', "output file (output format is always DER)"},
  33     {"i", OPT_INDENT, 0, "indents the output"},
  34     {"noout", OPT_NOOUT, 0, "do not produce any output"},
  35     {"offset", OPT_OFFSET, 'p', "offset into file"},
  36     {"length", OPT_LENGTH, 'p', "length of section in file"},
  37     {"oid", OPT_OID, '<', "file of extra oid definitions"},
  38     {"dump", OPT_DUMP, 0, "unknown data in hex form"},
  39     {"dlimit", OPT_DLIMIT, 'p',
  40      "dump the first arg bytes of unknown data in hex form"},
  41     {"strparse", OPT_STRPARSE, 's',
  42      "offset; a series of these can be used to 'dig'"},
  43     {OPT_MORE_STR, 0, 0, "into multiple ASN1 blob wrappings"},
  44     {"genstr", OPT_GENSTR, 's', "string to generate ASN1 structure from"},
  45     {"genconf", OPT_GENCONF, 's', "file to generate ASN1 structure from"},
  46     {OPT_MORE_STR, 0, 0, "(-inform  will be ignored)"},
  47     {"strictpem", OPT_STRICTPEM, 0,
  48      "do not attempt base64 decode outside PEM markers"},
  49     {"item", OPT_ITEM, 's', "item to parse and print"},
  50     {NULL}
  51 };
  52
  53 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf);
  54
  55 int asn1parse_main(int argc, char **argv)
  56 {
  57     ASN1_TYPE *at = NULL;
  58     BIO *in = NULL, *b64 = NULL, *derout = NULL;
  59     BUF_MEM *buf = NULL;
  60     STACK_OF(OPENSSL_STRING) *osk = NULL;
  61     char *genstr = NULL, *genconf = NULL;
  62     char *infile = NULL, *oidfile = NULL, *derfile = NULL;
  63     unsigned char *str = NULL;
  64     char *name = NULL, *header = NULL, *prog;
  65     const unsigned char *ctmpbuf;
  66     int indent = 0, noout = 0, dump = 0, strictpem = 0, informat = FORMAT_PEM;
  67     int offset = 0, ret = 1, i, j;
  68     long num, tmplen;
  69     unsigned char *tmpbuf;
  70     unsigned int length = 0;
  71     OPTION_CHOICE o;
  72     const ASN1_ITEM *it = NULL;
  73
  74     prog = opt_init(argc, argv, asn1parse_options);
  75
  76     if ((osk = sk_OPENSSL_STRING_new_null()) == NULL) {
  77         BIO_printf(bio_err, "%s: Memory allocation failure\n", prog);
  78         goto end;
  79     }
  80
  81     while ((o = opt_next()) != OPT_EOF) {
  82         switch (o) {
  83         case OPT_EOF:
  84         case OPT_ERR:
  85  opthelp:
  86             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  87             goto end;
  88         case OPT_HELP:
  89             opt_help(asn1parse_options);
  90             ret = 0;
  91             goto end;
  92         case OPT_INFORM:
  93             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  94                 goto opthelp;
  95             break;
  96         case OPT_IN:
  97             infile = opt_arg();
  98             break;
  99         case OPT_OUT:
 100             derfile = opt_arg();
 101             break;
 102         case OPT_INDENT:
 103             indent = 1;
 104             break;
 105         case OPT_NOOUT:
 106             noout = 1;
 107             break;
 108         case OPT_OID:
 109             oidfile = opt_arg();
 110             break;
 111         case OPT_OFFSET:
 112             offset = strtol(opt_arg(), NULL, 0);
 113             break;
 114         case OPT_LENGTH:
 115             length = atoi(opt_arg());
 116             break;
 117         case OPT_DUMP:
 118             dump = -1;
 119             break;
 120         case OPT_DLIMIT:
 121             dump = atoi(opt_arg());
 122             break;
 123         case OPT_STRPARSE:
 124             sk_OPENSSL_STRING_push(osk, opt_arg());
 125             break;
 126         case OPT_GENSTR:
 127             genstr = opt_arg();
 128             break;
 129         case OPT_GENCONF:
 130             genconf = opt_arg();
 131             break;
 132         case OPT_STRICTPEM:
 133             strictpem = 1;
 134             informat = FORMAT_PEM;
 135             break;
 136         case OPT_ITEM:
 137             it = ASN1_ITEM_lookup(opt_arg());
 138             if (it == NULL) {
 139                 size_t tmp;
 140
 141                 BIO_printf(bio_err, "Unknown item name %s\n", opt_arg());
 142                 BIO_puts(bio_err, "Supported types:\n");
 143                 for (tmp = 0;; tmp++) {
 144                     it = ASN1_ITEM_get(tmp);
 145                     if (it == NULL)
 146                         break;
 147                     BIO_printf(bio_err, "    %s\n", it->sname);
 148                 }
 149                 goto end;
 150             }
 151             break;
 152         }
 153     }
 154     argc = opt_num_rest();
 155     if (argc != 0)
 156         goto opthelp;
 157
 158     if (oidfile != NULL) {
 159         in = bio_open_default(oidfile, 'r', FORMAT_TEXT);
 160         if (in == NULL)
 161             goto end;
 162         OBJ_create_objects(in);
 163         BIO_free(in);
 164     }
 165
 166     if ((in = bio_open_default(infile, 'r', informat)) == NULL)
 167         goto end;
 168
 169     if (derfile && (derout = bio_open_default(derfile, 'w', FORMAT_ASN1)) == NULL)
 170         goto end;
 171
 172     if (strictpem) {
 173         if (PEM_read_bio(in, &name, &header, &str, &num) !=
 174             1) {
 175             BIO_printf(bio_err, "Error reading PEM file\n");
 176             ERR_print_errors(bio_err);
 177             goto end;
 178         }
 179     } else {
 180
 181         if ((buf = BUF_MEM_new()) == NULL)
 182             goto end;
 183         if (!BUF_MEM_grow(buf, BUFSIZ * 8))
 184             goto end;           /* Pre-allocate :-) */
 185
 186         if (genstr || genconf) {
 187             num = do_generate(genstr, genconf, buf);
 188             if (num < 0) {
 189                 ERR_print_errors(bio_err);
 190                 goto end;
 191             }
 192         } else {
 193
 194             if (informat == FORMAT_PEM) {
 195                 BIO *tmp;
 196
 197                 if ((b64 = BIO_new(BIO_f_base64())) == NULL)
 198                     goto end;
 199                 BIO_push(b64, in);
 200                 tmp = in;
 201                 in = b64;
 202                 b64 = tmp;
 203             }
 204
 205             num = 0;
 206             for (;;) {
 207                 if (!BUF_MEM_grow(buf, (int)num + BUFSIZ))
 208                     goto end;
 209                 i = BIO_read(in, &(buf->data[num]), BUFSIZ);
 210                 if (i <= 0)
 211                     break;
 212                 num += i;
 213             }
 214         }
 215         str = (unsigned char *)buf->data;
 216
 217     }
 218
 219     /* If any structs to parse go through in sequence */
 220
 221     if (sk_OPENSSL_STRING_num(osk)) {
 222         tmpbuf = str;
 223         tmplen = num;
 224         for (i = 0; i < sk_OPENSSL_STRING_num(osk); i++) {
 225             ASN1_TYPE *atmp;
 226             int typ;
 227             j = atoi(sk_OPENSSL_STRING_value(osk, i));
 228             if (j == 0) {
 229                 BIO_printf(bio_err, "'%s' is an invalid number\n",
 230                            sk_OPENSSL_STRING_value(osk, i));
 231                 continue;
 232             }
 233             tmpbuf += j;
 234             tmplen -= j;
 235             atmp = at;
 236             ctmpbuf = tmpbuf;
 237             at = d2i_ASN1_TYPE(NULL, &ctmpbuf, tmplen);
 238             ASN1_TYPE_free(atmp);
 239             if (!at) {
 240                 BIO_printf(bio_err, "Error parsing structure\n");
 241                 ERR_print_errors(bio_err);
 242                 goto end;
 243             }
 244             typ = ASN1_TYPE_get(at);
 245             if ((typ == V_ASN1_OBJECT)
 246                 || (typ == V_ASN1_BOOLEAN)
 247                 || (typ == V_ASN1_NULL)) {
 248                 BIO_printf(bio_err, "Can't parse %s type\n", ASN1_tag2str(typ));
 249                 ERR_print_errors(bio_err);
 250                 goto end;
 251             }
 252             /* hmm... this is a little evil but it works */
 253             tmpbuf = at->value.asn1_string->data;
 254             tmplen = at->value.asn1_string->length;
 255         }
 256         str = tmpbuf;
 257         num = tmplen;
 258     }
 259
 260     if (offset >= num) {
 261         BIO_printf(bio_err, "Error: offset too large\n");
 262         goto end;
 263     }
 264
 265     num -= offset;
 266
 267     if ((length == 0) || ((long)length > num))
 268         length = (unsigned int)num;
 269     if (derout != NULL) {
 270         if (BIO_write(derout, str + offset, length) != (int)length) {
 271             BIO_printf(bio_err, "Error writing output\n");
 272             ERR_print_errors(bio_err);
 273             goto end;
 274         }
 275     }
 276     if (!noout) {
 277         const unsigned char *p = str + offset;
 278
 279         if (it != NULL) {
 280             ASN1_VALUE *value = ASN1_item_d2i(NULL, &p, length, it);
 281             if (value == NULL) {
 282                 BIO_printf(bio_err, "Error parsing item %s\n", it->sname);
 283                 ERR_print_errors(bio_err);
 284                 goto end;
 285             }
 286             ASN1_item_print(bio_out, value, 0, it, NULL);
 287             ASN1_item_free(value, it);
 288         } else {
 289             if (!ASN1_parse_dump(bio_out, p, length, indent, dump)) {
 290                 ERR_print_errors(bio_err);
 291                 goto end;
 292             }
 293         }
 294     }
 295     ret = 0;
 296  end:
 297     BIO_free(derout);
 298     BIO_free(in);
 299     BIO_free(b64);
 300     if (ret != 0)
 301         ERR_print_errors(bio_err);
 302     BUF_MEM_free(buf);
 303     OPENSSL_free(name);
 304     OPENSSL_free(header);
 305     if (strictpem)
 306         OPENSSL_free(str);
 307     ASN1_TYPE_free(at);
 308     sk_OPENSSL_STRING_free(osk);
 309     return (ret);
 310 }
 311
 312 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf)
 313 {
 314     CONF *cnf = NULL;
 315     int len;
 316     unsigned char *p;
 317     ASN1_TYPE *atyp = NULL;
 318
 319     if (genconf != NULL) {
 320         if ((cnf = app_load_config(genconf)) == NULL)
 321             goto err;
 322         if (genstr == NULL)
 323             genstr = NCONF_get_string(cnf, "default", "asn1");
 324         if (genstr == NULL) {
 325             BIO_printf(bio_err, "Can't find 'asn1' in '%s'\n", genconf);
 326             goto err;
 327         }
 328     }
 329
 330     atyp = ASN1_generate_nconf(genstr, cnf);
 331     NCONF_free(cnf);
 332     cnf = NULL;
 333
 334     if (atyp == NULL)
 335         return -1;
 336
 337     len = i2d_ASN1_TYPE(atyp, NULL);
 338
 339     if (len <= 0)
 340         goto err;
 341
 342     if (!BUF_MEM_grow(buf, len))
 343         goto err;
 344
 345     p = (unsigned char *)buf->data;
 346
 347     i2d_ASN1_TYPE(atyp, &p);
 348
 349     ASN1_TYPE_free(atyp);
 350     return len;
 351
 352  err:
 353     NCONF_free(cnf);
 354     ASN1_TYPE_free(atyp);
 355     return -1;
 356 }