xref: /third_party/openssl/apps/asn1parse.c (revision e1051a39) 
1/*
2 * Copyright 1995-2021 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
21typedef 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
29const 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, '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    {"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     "do not attempt base64 decode outside PEM markers"},
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
59static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf);
60
61int 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, strictpem = 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_PEMDER, &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            strictpem = 1;
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    argc = opt_num_rest();
163    if (argc != 0)
164        goto opthelp;
165
166    if (oidfile != NULL) {
167        in = bio_open_default(oidfile, 'r', FORMAT_TEXT);
168        if (in == NULL)
169            goto end;
170        OBJ_create_objects(in);
171        BIO_free(in);
172    }
173
174    if ((in = bio_open_default(infile, 'r', informat)) == NULL)
175        goto end;
176
177    if (derfile && (derout = bio_open_default(derfile, 'w', FORMAT_ASN1)) == NULL)
178        goto end;
179
180    if ((buf = BUF_MEM_new()) == NULL)
181        goto end;
182    if (strictpem) {
183        if (PEM_read_bio(in, &name, &header, &str, &num) != 1) {
184            BIO_printf(bio_err, "Error reading PEM file\n");
185            ERR_print_errors(bio_err);
186            goto end;
187        }
188        buf->data = (char *)str;
189        buf->length = buf->max = num;
190    } else {
191        if (!BUF_MEM_grow(buf, BUFSIZ * 8))
192            goto end;           /* Pre-allocate :-) */
193
194        if (genstr || genconf) {
195            num = do_generate(genstr, genconf, buf);
196            if (num < 0) {
197                ERR_print_errors(bio_err);
198                goto end;
199            }
200        } else {
201
202            if (informat == FORMAT_PEM) {
203                BIO *tmp;
204
205                if ((b64 = BIO_new(BIO_f_base64())) == NULL)
206                    goto end;
207                BIO_push(b64, in);
208                tmp = in;
209                in = b64;
210                b64 = tmp;
211            }
212
213            num = 0;
214            for (;;) {
215                if (!BUF_MEM_grow(buf, num + BUFSIZ))
216                    goto end;
217                i = BIO_read(in, &(buf->data[num]), BUFSIZ);
218                if (i <= 0)
219                    break;
220                /* make sure num doesn't overflow */
221                if (i > LONG_MAX - num)
222                    goto end;
223                num += i;
224            }
225        }
226        str = (unsigned char *)buf->data;
227
228    }
229
230    /* If any structs to parse go through in sequence */
231
232    if (sk_OPENSSL_STRING_num(osk)) {
233        tmpbuf = str;
234        tmplen = num;
235        for (i = 0; i < sk_OPENSSL_STRING_num(osk); i++) {
236            ASN1_TYPE *atmp;
237            int typ;
238            j = strtol(sk_OPENSSL_STRING_value(osk, i), NULL, 0);
239            if (j <= 0 || j >= tmplen) {
240                BIO_printf(bio_err, "'%s' is out of range\n",
241                           sk_OPENSSL_STRING_value(osk, i));
242                continue;
243            }
244            tmpbuf += j;
245            tmplen -= j;
246            atmp = at;
247            ctmpbuf = tmpbuf;
248            at = d2i_ASN1_TYPE(NULL, &ctmpbuf, tmplen);
249            ASN1_TYPE_free(atmp);
250            if (!at) {
251                BIO_printf(bio_err, "Error parsing structure\n");
252                ERR_print_errors(bio_err);
253                goto end;
254            }
255            typ = ASN1_TYPE_get(at);
256            if ((typ == V_ASN1_OBJECT)
257                || (typ == V_ASN1_BOOLEAN)
258                || (typ == V_ASN1_NULL)) {
259                BIO_printf(bio_err, "Can't parse %s type\n", ASN1_tag2str(typ));
260                ERR_print_errors(bio_err);
261                goto end;
262            }
263            /* hmm... this is a little evil but it works */
264            tmpbuf = at->value.asn1_string->data;
265            tmplen = at->value.asn1_string->length;
266        }
267        str = tmpbuf;
268        num = tmplen;
269    }
270
271    if (offset < 0 || offset >= num) {
272        BIO_printf(bio_err, "Error: offset out of range\n");
273        goto end;
274    }
275
276    num -= offset;
277
278    if (length == 0 || length > (unsigned int)num)
279        length = (unsigned int)num;
280    if (derout != NULL) {
281        if (BIO_write(derout, str + offset, length) != (int)length) {
282            BIO_printf(bio_err, "Error writing output\n");
283            ERR_print_errors(bio_err);
284            goto end;
285        }
286    }
287    if (!noout) {
288        const unsigned char *p = str + offset;
289
290        if (it != NULL) {
291            ASN1_VALUE *value = ASN1_item_d2i(NULL, &p, length, it);
292            if (value == NULL) {
293                BIO_printf(bio_err, "Error parsing item %s\n", it->sname);
294                ERR_print_errors(bio_err);
295                goto end;
296            }
297            ASN1_item_print(bio_out, value, 0, it, NULL);
298            ASN1_item_free(value, it);
299        } else {
300            if (!ASN1_parse_dump(bio_out, p, length, indent, dump)) {
301                ERR_print_errors(bio_err);
302                goto end;
303            }
304        }
305    }
306    ret = 0;
307 end:
308    BIO_free(derout);
309    BIO_free(in);
310    BIO_free(b64);
311    if (ret != 0)
312        ERR_print_errors(bio_err);
313    BUF_MEM_free(buf);
314    OPENSSL_free(name);
315    OPENSSL_free(header);
316    ASN1_TYPE_free(at);
317    sk_OPENSSL_STRING_free(osk);
318    return ret;
319}
320
321static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf)
322{
323    CONF *cnf = NULL;
324    int len;
325    unsigned char *p;
326    ASN1_TYPE *atyp = NULL;
327
328    if (genconf != NULL) {
329        if ((cnf = app_load_config(genconf)) == NULL)
330            goto err;
331        if (genstr == NULL)
332            genstr = NCONF_get_string(cnf, "default", "asn1");
333        if (genstr == NULL) {
334            BIO_printf(bio_err, "Can't find 'asn1' in '%s'\n", genconf);
335            goto err;
336        }
337    }
338
339    atyp = ASN1_generate_nconf(genstr, cnf);
340    NCONF_free(cnf);
341    cnf = NULL;
342
343    if (atyp == NULL)
344        return -1;
345
346    len = i2d_ASN1_TYPE(atyp, NULL);
347
348    if (len <= 0)
349        goto err;
350
351    if (!BUF_MEM_grow(buf, len))
352        goto err;
353
354    p = (unsigned char *)buf->data;
355
356    i2d_ASN1_TYPE(atyp, &p);
357
358    ASN1_TYPE_free(atyp);
359    return len;
360
361 err:
362    NCONF_free(cnf);
363    ASN1_TYPE_free(atyp);
364    return -1;
365}
366