apps/asn1parse.c

   1 /*
   2  * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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 "progs.h"
  15 #include <openssl/err.h>
  16 #include <openssl/evp.h>
  17 #include <openssl/x509.h>
  18 #include <openssl/pem.h>
  19 #include <openssl/asn1t.h>
  20
  21 typedef enum OPTION_choice {
  22     OPT_COMMON,
  23     OPT_INFORM, OPT_IN, OPT_OUT, OPT_INDENT, OPT_NOOUT,
  24     OPT_OID, OPT_OFFSET, OPT_LENGTH, OPT_DUMP, OPT_DLIMIT,
  25     OPT_STRPARSE, OPT_GENSTR, OPT_GENCONF, OPT_STRICTPEM,
  26     OPT_ITEM
  27 } OPTION_CHOICE;
  28
  29 const OPTIONS asn1parse_options[] = {
  30     OPT_SECTION("General"),
  31     {"help", OPT_HELP, '-', "Display this summary"},
  32     {"oid", OPT_OID, '<', "file of extra oid definitions"},
  33
  34     OPT_SECTION("I/O"),
  35     {"inform", OPT_INFORM, 'A', "input format - one of DER PEM B64"},
  36     {"in", OPT_IN, '<', "input file"},
  37     {"out", OPT_OUT, '>', "output file (output format is always DER)"},
  38     {"noout", OPT_NOOUT, 0, "do not produce any output"},
  39     {"offset", OPT_OFFSET, 'p', "offset into file"},
  40     {"length", OPT_LENGTH, 'p', "length of section in file"},
  41     {"strparse", OPT_STRPARSE, 'p',
  42      "offset; a series of these can be used to 'dig'"},
  43     {"genstr", OPT_GENSTR, 's', "string to generate ASN1 structure from"},
  44     {OPT_MORE_STR, 0, 0, "into multiple ASN1 blob wrappings"},
  45     {"genconf", OPT_GENCONF, 's', "file to generate ASN1 structure from"},
  46     {"strictpem", OPT_STRICTPEM, 0,
  47      "equivalent to '-inform pem' (obsolete)"},
  48     {"item", OPT_ITEM, 's', "item to parse and print"},
  49     {OPT_MORE_STR, 0, 0, "(-inform  will be ignored)"},
  50
  51     OPT_SECTION("Formatting"),
  52     {"i", OPT_INDENT, 0, "indents the output"},
  53     {"dump", OPT_DUMP, 0, "unknown data in hex form"},
  54     {"dlimit", OPT_DLIMIT, 'p',
  55      "dump the first arg bytes of unknown data in hex form"},
  56     {NULL}
  57 };
  58
  59 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf);
  60
  61 int asn1parse_main(int argc, char **argv)
  62 {
  63     ASN1_TYPE *at = NULL;
  64     BIO *in = NULL, *b64 = NULL, *derout = NULL;
  65     BUF_MEM *buf = NULL;
  66     STACK_OF(OPENSSL_STRING) *osk = NULL;
  67     char *genstr = NULL, *genconf = NULL;
  68     char *infile = NULL, *oidfile = NULL, *derfile = NULL;
  69     unsigned char *str = NULL;
  70     char *name = NULL, *header = NULL, *prog;
  71     const unsigned char *ctmpbuf;
  72     int indent = 0, noout = 0, dump = 0, informat = FORMAT_PEM;
  73     int offset = 0, ret = 1, i, j;
  74     long num, tmplen;
  75     unsigned char *tmpbuf;
  76     unsigned int length = 0;
  77     OPTION_CHOICE o;
  78     const ASN1_ITEM *it = NULL;
  79
  80     prog = opt_init(argc, argv, asn1parse_options);
  81
  82     if ((osk = sk_OPENSSL_STRING_new_null()) == NULL) {
  83         BIO_printf(bio_err, "%s: Memory allocation failure\n", prog);
  84         goto end;
  85     }
  86
  87     while ((o = opt_next()) != OPT_EOF) {
  88         switch (o) {
  89         case OPT_EOF:
  90         case OPT_ERR:
  91  opthelp:
  92             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  93             goto end;
  94         case OPT_HELP:
  95             opt_help(asn1parse_options);
  96             ret = 0;
  97             goto end;
  98         case OPT_INFORM:
  99             if (!opt_format(opt_arg(), OPT_FMT_ASN1, &informat))
 100                 goto opthelp;
 101             break;
 102         case OPT_IN:
 103             infile = opt_arg();
 104             break;
 105         case OPT_OUT:
 106             derfile = opt_arg();
 107             break;
 108         case OPT_INDENT:
 109             indent = 1;
 110             break;
 111         case OPT_NOOUT:
 112             noout = 1;
 113             break;
 114         case OPT_OID:
 115             oidfile = opt_arg();
 116             break;
 117         case OPT_OFFSET:
 118             offset = strtol(opt_arg(), NULL, 0);
 119             break;
 120         case OPT_LENGTH:
 121             length = strtol(opt_arg(), NULL, 0);
 122             break;
 123         case OPT_DUMP:
 124             dump = -1;
 125             break;
 126         case OPT_DLIMIT:
 127             dump = strtol(opt_arg(), NULL, 0);
 128             break;
 129         case OPT_STRPARSE:
 130             sk_OPENSSL_STRING_push(osk, opt_arg());
 131             break;
 132         case OPT_GENSTR:
 133             genstr = opt_arg();
 134             break;
 135         case OPT_GENCONF:
 136             genconf = opt_arg();
 137             break;
 138         case OPT_STRICTPEM:
 139             /* accepted for backward compatibility */
 140             informat = FORMAT_PEM;
 141             break;
 142         case OPT_ITEM:
 143             it = ASN1_ITEM_lookup(opt_arg());
 144             if (it == NULL) {
 145                 size_t tmp;
 146
 147                 BIO_printf(bio_err, "Unknown item name %s\n", opt_arg());
 148                 BIO_puts(bio_err, "Supported types:\n");
 149                 for (tmp = 0;; tmp++) {
 150                     it = ASN1_ITEM_get(tmp);
 151                     if (it == NULL)
 152                         break;
 153                     BIO_printf(bio_err, "    %s\n", it->sname);
 154                 }
 155                 goto end;
 156             }
 157             break;
 158         }
 159     }
 160
 161     /* No extra args. */
 162     if (!opt_check_rest_arg(NULL))
 163         goto opthelp;
 164
 165     if (oidfile != NULL) {
 166         in = bio_open_default(oidfile, 'r', FORMAT_TEXT);
 167         if (in == NULL)
 168             goto end;
 169         OBJ_create_objects(in);
 170         BIO_free(in);
 171     }
 172
 173     if ((in = bio_open_default(infile, 'r', informat)) == NULL)
 174         goto end;
 175
 176     if (derfile && (derout = bio_open_default(derfile, 'w', FORMAT_ASN1)) == NULL)
 177         goto end;
 178
 179     if ((buf = BUF_MEM_new()) == NULL)
 180         goto end;
 181     if (informat == FORMAT_PEM) {
 182         if (PEM_read_bio(in, &name, &header, &str, &num) != 1) {
 183             BIO_printf(bio_err, "Error reading PEM file\n");
 184             ERR_print_errors(bio_err);
 185             goto end;
 186         }
 187         buf->data = (char *)str;
 188         buf->length = buf->max = num;
 189     } else {
 190         if (!BUF_MEM_grow(buf, BUFSIZ * 8))
 191             goto end;           /* Pre-allocate :-) */
 192
 193         if (genstr || genconf) {
 194             num = do_generate(genstr, genconf, buf);
 195             if (num < 0) {
 196                 ERR_print_errors(bio_err);
 197                 goto end;
 198             }
 199         } else {
 200
 201             if (informat == FORMAT_BASE64) {
 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, 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 = strtol(sk_OPENSSL_STRING_value(osk, i), NULL, 0);
 235             if (j <= 0 || j >= tmplen) {
 236                 BIO_printf(bio_err, "'%s' is out of range\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 < 0 || offset >= num) {
 268         BIO_printf(bio_err, "Error: offset out of range\n");
 269         goto end;
 270     }
 271
 272     num -= offset;
 273
 274     if (length == 0 || length > (unsigned int)num)
 275         length = (unsigned int)num;
 276     if (derout != NULL) {
 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     ASN1_TYPE_free(at);
 313     sk_OPENSSL_STRING_free(osk);
 314     return ret;
 315 }
 316
 317 static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf)
 318 {
 319     CONF *cnf = NULL;
 320     int len;
 321     unsigned char *p;
 322     ASN1_TYPE *atyp = NULL;
 323
 324     if (genconf != NULL) {
 325         if ((cnf = app_load_config(genconf)) == NULL)
 326             goto err;
 327         if (genstr == NULL)
 328             genstr = NCONF_get_string(cnf, "default", "asn1");
 329         if (genstr == NULL) {
 330             BIO_printf(bio_err, "Can't find 'asn1' in '%s'\n", genconf);
 331             goto err;
 332         }
 333     }
 334
 335     atyp = ASN1_generate_nconf(genstr, cnf);
 336     NCONF_free(cnf);
 337     cnf = NULL;
 338
 339     if (atyp == NULL)
 340         return -1;
 341
 342     len = i2d_ASN1_TYPE(atyp, NULL);
 343
 344     if (len <= 0)
 345         goto err;
 346
 347     if (!BUF_MEM_grow(buf, len))
 348         goto err;
 349
 350     p = (unsigned char *)buf->data;
 351
 352     i2d_ASN1_TYPE(atyp, &p);
 353
 354     ASN1_TYPE_free(atyp);
 355     return len;
 356
 357  err:
 358     NCONF_free(cnf);
 359     ASN1_TYPE_free(atyp);
 360     return -1;
 361 }