apps/asn1pars.c

   1 /*
   2  * Copyright 1995-2016 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 /*
  11  * A nice addition from Dr Stephen Henson <steve@openssl.org> to add the
  12  * -strparse option which parses nested binary structures
  13  */
  14
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include "apps.h"
  19 #include <openssl/err.h>
  20 #include <openssl/evp.h>
  21 #include <openssl/x509.h>
  22 #include <openssl/pem.h>
  23 #include <openssl/asn1t.h>
  24
  25 typedef enum OPTION_choice {
  26     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  27     OPT_INFORM, OPT_IN, OPT_OUT, OPT_INDENT, OPT_NOOUT,
  28     OPT_OID, OPT_OFFSET, OPT_LENGTH, OPT_DUMP, OPT_DLIMIT,
  29     OPT_STRPARSE, OPT_GENSTR, OPT_GENCONF, OPT_STRICTPEM,
  30     OPT_ITEM
  31 } OPTION_CHOICE;
  32
  33 OPTIONS asn1parse_options[] = {
  34     {"help", OPT_HELP, '-', "Display this summary"},
  35     {"inform", OPT_INFORM, 'F', "input format - one of DER PEM"},
  36     {"in", OPT_IN, '<', "input file"},
  37     {"out", OPT_OUT, '>', "output file (output format is always DER)"},
  38     {"i", OPT_INDENT, 0, "indents the output"},
  39     {"noout", OPT_NOOUT, 0, "do not produce any output"},
  40     {"offset", OPT_OFFSET, 'p', "offset into file"},
  41     {"length", OPT_LENGTH, 'p', "length of section in file"},
  42     {"oid", OPT_OID, '<', "file of extra oid definitions"},
  43     {"dump", OPT_DUMP, 0, "unknown data in hex form"},
  44     {"dlimit", OPT_DLIMIT, 'p',
  45      "dump the first arg bytes of unknown data in hex form"},
  46     {"strparse", OPT_STRPARSE, 's',
  47      "offset; a series of these can be used to 'dig'"},
  48     {OPT_MORE_STR, 0, 0, "into multiple ASN1 blob wrappings"},
  49     {"genstr", OPT_GENSTR, 's', "string to generate ASN1 structure from"},
  50     {"genconf", OPT_GENCONF, 's', "file to generate ASN1 structure from"},
  51     {OPT_MORE_STR, 0, 0, "(-inform  will be ignored)"},
  52     {"strictpem", OPT_STRICTPEM, 0,
  53      "do not attempt base64 decode outside PEM markers"},
  54     {"item", OPT_ITEM, 's', "item to parse and print"},
  55     {NULL}
  56 };
  57
  58 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf);
  59
  60 int asn1parse_main(int argc, char **argv)
  61 {
  62     ASN1_TYPE *at = NULL;
  63     BIO *in = NULL, *b64 = NULL, *derout = NULL;
  64     BUF_MEM *buf = NULL;
  65     STACK_OF(OPENSSL_STRING) *osk = NULL;
  66     char *genstr = NULL, *genconf = NULL;
  67     char *infile = NULL, *oidfile = NULL, *derfile = NULL;
  68     unsigned char *str = NULL;
  69     char *name = NULL, *header = NULL, *prog;
  70     const unsigned char *ctmpbuf;
  71     int indent = 0, noout = 0, dump = 0, strictpem = 0, informat = FORMAT_PEM;
  72     int offset = 0, ret = 1, i, j;
  73     long num, tmplen;
  74     unsigned char *tmpbuf;
  75     unsigned int length = 0;
  76     OPTION_CHOICE o;
  77     const ASN1_ITEM *it = NULL;
  78
  79     prog = opt_init(argc, argv, asn1parse_options);
  80
  81     if ((osk = sk_OPENSSL_STRING_new_null()) == NULL) {
  82         BIO_printf(bio_err, "%s: Memory allocation failure\n", prog);
  83         goto end;
  84     }
  85
  86     while ((o = opt_next()) != OPT_EOF) {
  87         switch (o) {
  88         case OPT_EOF:
  89         case OPT_ERR:
  90  opthelp:
  91             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  92             goto end;
  93         case OPT_HELP:
  94             opt_help(asn1parse_options);
  95             ret = 0;
  96             goto end;
  97         case OPT_INFORM:
  98             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  99                 goto opthelp;
 100             break;
 101         case OPT_IN:
 102             infile = opt_arg();
 103             break;
 104         case OPT_OUT:
 105             derfile = opt_arg();
 106             break;
 107         case OPT_INDENT:
 108             indent = 1;
 109             break;
 110         case OPT_NOOUT:
 111             noout = 1;
 112             break;
 113         case OPT_OID:
 114             oidfile = opt_arg();
 115             break;
 116         case OPT_OFFSET:
 117             offset = strtol(opt_arg(), NULL, 0);
 118             break;
 119         case OPT_LENGTH:
 120             length = atoi(opt_arg());
 121             break;
 122         case OPT_DUMP:
 123             dump = -1;
 124             break;
 125         case OPT_DLIMIT:
 126             dump = atoi(opt_arg());
 127             break;
 128         case OPT_STRPARSE:
 129             sk_OPENSSL_STRING_push(osk, opt_arg());
 130             break;
 131         case OPT_GENSTR:
 132             genstr = opt_arg();
 133             break;
 134         case OPT_GENCONF:
 135             genconf = opt_arg();
 136             break;
 137         case OPT_STRICTPEM:
 138             strictpem = 1;
 139             informat = FORMAT_PEM;
 140             break;
 141         case OPT_ITEM:
 142             it = ASN1_ITEM_lookup(opt_arg());
 143             if (it == NULL) {
 144                 size_t tmp;
 145
 146                 BIO_printf(bio_err, "Unknown item name %s\n", opt_arg());
 147                 BIO_puts(bio_err, "Supported types:\n");
 148                 for (tmp = 0;; tmp++) {
 149                     it = ASN1_ITEM_get(tmp);
 150                     if (it == NULL)
 151                         break;
 152                     BIO_printf(bio_err, "    %s\n", it->sname);
 153                 }
 154                 goto end;
 155             }
 156             break;
 157         }
 158     }
 159     argc = opt_num_rest();
 160     if (argc != 0)
 161         goto opthelp;
 162
 163     if (oidfile != NULL) {
 164         in = bio_open_default(oidfile, 'r', FORMAT_TEXT);
 165         if (in == NULL)
 166             goto end;
 167         OBJ_create_objects(in);
 168         BIO_free(in);
 169     }
 170
 171     if ((in = bio_open_default(infile, 'r', informat)) == NULL)
 172         goto end;
 173
 174     if (derfile && (derout = bio_open_default(derfile, 'w', FORMAT_ASN1)) == NULL)
 175         goto end;
 176
 177     if (strictpem) {
 178         if (PEM_read_bio(in, &name, &header, &str, &num) !=
 179             1) {
 180             BIO_printf(bio_err, "Error reading PEM file\n");
 181             ERR_print_errors(bio_err);
 182             goto end;
 183         }
 184     } else {
 185
 186         if ((buf = BUF_MEM_new()) == NULL)
 187             goto end;
 188         if (!BUF_MEM_grow(buf, BUFSIZ * 8))
 189             goto end;           /* Pre-allocate :-) */
 190
 191         if (genstr || genconf) {
 192             num = do_generate(genstr, genconf, buf);
 193             if (num < 0) {
 194                 ERR_print_errors(bio_err);
 195                 goto end;
 196             }
 197         }
 198
 199         else {
 200
 201             if (informat == FORMAT_PEM) {
 202                 BIO *tmp;
 203
 204                 if ((b64 = BIO_new(BIO_f_base64())) == NULL)
 205                     goto end;
 206                 BIO_push(b64, in);
 207                 tmp = in;
 208                 in = b64;
 209                 b64 = tmp;
 210             }
 211
 212             num = 0;
 213             for (;;) {
 214                 if (!BUF_MEM_grow(buf, (int)num + BUFSIZ))
 215                     goto end;
 216                 i = BIO_read(in, &(buf->data[num]), BUFSIZ);
 217                 if (i <= 0)
 218                     break;
 219                 num += i;
 220             }
 221         }
 222         str = (unsigned char *)buf->data;
 223
 224     }
 225
 226     /* If any structs to parse go through in sequence */
 227
 228     if (sk_OPENSSL_STRING_num(osk)) {
 229         tmpbuf = str;
 230         tmplen = num;
 231         for (i = 0; i < sk_OPENSSL_STRING_num(osk); i++) {
 232             ASN1_TYPE *atmp;
 233             int typ;
 234             j = atoi(sk_OPENSSL_STRING_value(osk, i));
 235             if (j == 0) {
 236                 BIO_printf(bio_err, "'%s' is an invalid number\n",
 237                            sk_OPENSSL_STRING_value(osk, i));
 238                 continue;
 239             }
 240             tmpbuf += j;
 241             tmplen -= j;
 242             atmp = at;
 243             ctmpbuf = tmpbuf;
 244             at = d2i_ASN1_TYPE(NULL, &ctmpbuf, tmplen);
 245             ASN1_TYPE_free(atmp);
 246             if (!at) {
 247                 BIO_printf(bio_err, "Error parsing structure\n");
 248                 ERR_print_errors(bio_err);
 249                 goto end;
 250             }
 251             typ = ASN1_TYPE_get(at);
 252             if ((typ == V_ASN1_OBJECT)
 253                 || (typ == V_ASN1_BOOLEAN)
 254                 || (typ == V_ASN1_NULL)) {
 255                 BIO_printf(bio_err, "Can't parse %s type\n", ASN1_tag2str(typ));
 256                 ERR_print_errors(bio_err);
 257                 goto end;
 258             }
 259             /* hmm... this is a little evil but it works */
 260             tmpbuf = at->value.asn1_string->data;
 261             tmplen = at->value.asn1_string->length;
 262         }
 263         str = tmpbuf;
 264         num = tmplen;
 265     }
 266
 267     if (offset >= num) {
 268         BIO_printf(bio_err, "Error: offset too large\n");
 269         goto end;
 270     }
 271
 272     num -= offset;
 273
 274     if ((length == 0) || ((long)length > num))
 275         length = (unsigned int)num;
 276     if (derout) {
 277         if (BIO_write(derout, str + offset, length) != (int)length) {
 278             BIO_printf(bio_err, "Error writing output\n");
 279             ERR_print_errors(bio_err);
 280             goto end;
 281         }
 282     }
 283     if (!noout) {
 284         const unsigned char *p = str + offset;
 285
 286         if (it != NULL) {
 287             ASN1_VALUE *value = ASN1_item_d2i(NULL, &p, length, it);
 288             if (value == NULL) {
 289                 BIO_printf(bio_err, "Error parsing item %s\n", it->sname);
 290                 ERR_print_errors(bio_err);
 291                 goto end;
 292             }
 293             ASN1_item_print(bio_out, value, 0, it, NULL);
 294             ASN1_item_free(value, it);
 295         } else {
 296             if (!ASN1_parse_dump(bio_out, p, length, indent, dump)) {
 297                 ERR_print_errors(bio_err);
 298                 goto end;
 299             }
 300         }
 301     }
 302     ret = 0;
 303  end:
 304     BIO_free(derout);
 305     BIO_free(in);
 306     BIO_free(b64);
 307     if (ret != 0)
 308         ERR_print_errors(bio_err);
 309     BUF_MEM_free(buf);
 310     OPENSSL_free(name);
 311     OPENSSL_free(header);
 312     if (strictpem)
 313         OPENSSL_free(str);
 314     ASN1_TYPE_free(at);
 315     sk_OPENSSL_STRING_free(osk);
 316     return (ret);
 317 }
 318
 319 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf)
 320 {
 321     CONF *cnf = NULL;
 322     int len;
 323     unsigned char *p;
 324     ASN1_TYPE *atyp = NULL;
 325
 326     if (genconf) {
 327         if ((cnf = app_load_config(genconf)) == NULL)
 328             goto err;
 329         if (!genstr)
 330             genstr = NCONF_get_string(cnf, "default", "asn1");
 331         if (!genstr) {
 332             BIO_printf(bio_err, "Can't find 'asn1' in '%s'\n", genconf);
 333             goto err;
 334         }
 335     }
 336
 337     atyp = ASN1_generate_nconf(genstr, cnf);
 338     NCONF_free(cnf);
 339     cnf = NULL;
 340
 341     if (!atyp)
 342         return -1;
 343
 344     len = i2d_ASN1_TYPE(atyp, NULL);
 345
 346     if (len <= 0)
 347         goto err;
 348
 349     if (!BUF_MEM_grow(buf, len))
 350         goto err;
 351
 352     p = (unsigned char *)buf->data;
 353
 354     i2d_ASN1_TYPE(atyp, &p);
 355
 356     ASN1_TYPE_free(atyp);
 357     return len;
 358
 359  err:
 360     NCONF_free(cnf);
 361     ASN1_TYPE_free(atyp);
 362     return -1;
 363 }