1/*
2 * Copyright 1995-2019 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 "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_ERR = -1, OPT_EOF = 0, OPT_HELP,
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    {"help", OPT_HELP, '-', "Display this summary"},
31    {"inform", OPT_INFORM, 'F', "input format - one of DER PEM"},
32    {"in", OPT_IN, '<', "input file"},
33    {"out", OPT_OUT, '>', "output file (output format is always DER)"},
34    {"i", OPT_INDENT, 0, "indents the output"},
35    {"noout", OPT_NOOUT, 0, "do not produce any output"},
36    {"offset", OPT_OFFSET, 'p', "offset into file"},
37    {"length", OPT_LENGTH, 'p', "length of section in file"},
38    {"oid", OPT_OID, '<', "file of extra oid definitions"},
39    {"dump", OPT_DUMP, 0, "unknown data in hex form"},
40    {"dlimit", OPT_DLIMIT, 'p',
41     "dump the first arg bytes of unknown data in hex form"},
42    {"strparse", OPT_STRPARSE, 'p',
43     "offset; a series of these can be used to 'dig'"},
44    {OPT_MORE_STR, 0, 0, "into multiple ASN1 blob wrappings"},
45    {"genstr", OPT_GENSTR, 's', "string to generate ASN1 structure from"},
46    {"genconf", OPT_GENCONF, 's', "file to generate ASN1 structure from"},
47    {OPT_MORE_STR, 0, 0, "(-inform  will be ignored)"},
48    {"strictpem", OPT_STRICTPEM, 0,
49     "do not attempt base64 decode outside PEM markers"},
50    {"item", OPT_ITEM, 's', "item to parse and print"},
51    {NULL}
52};
53
54static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf);
55
56int asn1parse_main(int argc, char **argv)
57{
58    ASN1_TYPE *at = NULL;
59    BIO *in = NULL, *b64 = NULL, *derout = NULL;
60    BUF_MEM *buf = NULL;
61    STACK_OF(OPENSSL_STRING) *osk = NULL;
62    char *genstr = NULL, *genconf = NULL;
63    char *infile = NULL, *oidfile = NULL, *derfile = NULL;
64    unsigned char *str = NULL;
65    char *name = NULL, *header = NULL, *prog;
66    const unsigned char *ctmpbuf;
67    int indent = 0, noout = 0, dump = 0, strictpem = 0, informat = FORMAT_PEM;
68    int offset = 0, ret = 1, i, j;
69    long num, tmplen;
70    unsigned char *tmpbuf;
71    unsigned int length = 0;
72    OPTION_CHOICE o;
73    const ASN1_ITEM *it = NULL;
74
75    prog = opt_init(argc, argv, asn1parse_options);
76
77    if ((osk = sk_OPENSSL_STRING_new_null()) == NULL) {
78        BIO_printf(bio_err, "%s: Memory allocation failure\n", prog);
79        goto end;
80    }
81
82    while ((o = opt_next()) != OPT_EOF) {
83        switch (o) {
84        case OPT_EOF:
85        case OPT_ERR:
86 opthelp:
87            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
88            goto end;
89        case OPT_HELP:
90            opt_help(asn1parse_options);
91            ret = 0;
92            goto end;
93        case OPT_INFORM:
94            if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
95                goto opthelp;
96            break;
97        case OPT_IN:
98            infile = opt_arg();
99            break;
100        case OPT_OUT:
101            derfile = opt_arg();
102            break;
103        case OPT_INDENT:
104            indent = 1;
105            break;
106        case OPT_NOOUT:
107            noout = 1;
108            break;
109        case OPT_OID:
110            oidfile = opt_arg();
111            break;
112        case OPT_OFFSET:
113            offset = strtol(opt_arg(), NULL, 0);
114            break;
115        case OPT_LENGTH:
116            length = strtol(opt_arg(), NULL, 0);
117            break;
118        case OPT_DUMP:
119            dump = -1;
120            break;
121        case OPT_DLIMIT:
122            dump = strtol(opt_arg(), NULL, 0);
123            break;
124        case OPT_STRPARSE:
125            sk_OPENSSL_STRING_push(osk, opt_arg());
126            break;
127        case OPT_GENSTR:
128            genstr = opt_arg();
129            break;
130        case OPT_GENCONF:
131            genconf = opt_arg();
132            break;
133        case OPT_STRICTPEM:
134            strictpem = 1;
135            informat = FORMAT_PEM;
136            break;
137        case OPT_ITEM:
138            it = ASN1_ITEM_lookup(opt_arg());
139            if (it == NULL) {
140                size_t tmp;
141
142                BIO_printf(bio_err, "Unknown item name %s\n", opt_arg());
143                BIO_puts(bio_err, "Supported types:\n");
144                for (tmp = 0;; tmp++) {
145                    it = ASN1_ITEM_get(tmp);
146                    if (it == NULL)
147                        break;
148                    BIO_printf(bio_err, "    %s\n", it->sname);
149                }
150                goto end;
151            }
152            break;
153        }
154    }
155    argc = opt_num_rest();
156    if (argc != 0)
157        goto opthelp;
158
159    if (oidfile != NULL) {
160        in = bio_open_default(oidfile, 'r', FORMAT_TEXT);
161        if (in == NULL)
162            goto end;
163        OBJ_create_objects(in);
164        BIO_free(in);
165    }
166
167    if ((in = bio_open_default(infile, 'r', informat)) == NULL)
168        goto end;
169
170    if (derfile && (derout = bio_open_default(derfile, 'w', FORMAT_ASN1)) == NULL)
171        goto end;
172
173    if ((buf = BUF_MEM_new()) == NULL)
174        goto end;
175    if (strictpem) {
176        if (PEM_read_bio(in, &name, &header, &str, &num) != 1) {
177            BIO_printf(bio_err, "Error reading PEM file\n");
178            ERR_print_errors(bio_err);
179            goto end;
180        }
181        buf->data = (char *)str;
182        buf->length = buf->max = num;
183    } else {
184        if (!BUF_MEM_grow(buf, BUFSIZ * 8))
185            goto end;           /* Pre-allocate :-) */
186
187        if (genstr || genconf) {
188            num = do_generate(genstr, genconf, buf);
189            if (num < 0) {
190                ERR_print_errors(bio_err);
191                goto end;
192            }
193        } else {
194
195            if (informat == FORMAT_PEM) {
196                BIO *tmp;
197
198                if ((b64 = BIO_new(BIO_f_base64())) == NULL)
199                    goto end;
200                BIO_push(b64, in);
201                tmp = in;
202                in = b64;
203                b64 = tmp;
204            }
205
206            num = 0;
207            for (;;) {
208                if (!BUF_MEM_grow(buf, num + BUFSIZ))
209                    goto end;
210                i = BIO_read(in, &(buf->data[num]), BUFSIZ);
211                if (i <= 0)
212                    break;
213                num += i;
214            }
215        }
216        str = (unsigned char *)buf->data;
217
218    }
219
220    /* If any structs to parse go through in sequence */
221
222    if (sk_OPENSSL_STRING_num(osk)) {
223        tmpbuf = str;
224        tmplen = num;
225        for (i = 0; i < sk_OPENSSL_STRING_num(osk); i++) {
226            ASN1_TYPE *atmp;
227            int typ;
228            j = strtol(sk_OPENSSL_STRING_value(osk, i), NULL, 0);
229            if (j <= 0 || j >= tmplen) {
230                BIO_printf(bio_err, "'%s' is out of range\n",
231                           sk_OPENSSL_STRING_value(osk, i));
232                continue;
233            }
234            tmpbuf += j;
235            tmplen -= j;
236            atmp = at;
237            ctmpbuf = tmpbuf;
238            at = d2i_ASN1_TYPE(NULL, &ctmpbuf, tmplen);
239            ASN1_TYPE_free(atmp);
240            if (!at) {
241                BIO_printf(bio_err, "Error parsing structure\n");
242                ERR_print_errors(bio_err);
243                goto end;
244            }
245            typ = ASN1_TYPE_get(at);
246            if ((typ == V_ASN1_OBJECT)
247                || (typ == V_ASN1_BOOLEAN)
248                || (typ == V_ASN1_NULL)) {
249                BIO_printf(bio_err, "Can't parse %s type\n", ASN1_tag2str(typ));
250                ERR_print_errors(bio_err);
251                goto end;
252            }
253            /* hmm... this is a little evil but it works */
254            tmpbuf = at->value.asn1_string->data;
255            tmplen = at->value.asn1_string->length;
256        }
257        str = tmpbuf;
258        num = tmplen;
259    }
260
261    if (offset < 0 || offset >= num) {
262        BIO_printf(bio_err, "Error: offset out of range\n");
263        goto end;
264    }
265
266    num -= offset;
267
268    if (length == 0 || length > (unsigned int)num)
269        length = (unsigned int)num;
270    if (derout != NULL) {
271        if (BIO_write(derout, str + offset, length) != (int)length) {
272            BIO_printf(bio_err, "Error writing output\n");
273            ERR_print_errors(bio_err);
274            goto end;
275        }
276    }
277    if (!noout) {
278        const unsigned char *p = str + offset;
279
280        if (it != NULL) {
281            ASN1_VALUE *value = ASN1_item_d2i(NULL, &p, length, it);
282            if (value == NULL) {
283                BIO_printf(bio_err, "Error parsing item %s\n", it->sname);
284                ERR_print_errors(bio_err);
285                goto end;
286            }
287            ASN1_item_print(bio_out, value, 0, it, NULL);
288            ASN1_item_free(value, it);
289        } else {
290            if (!ASN1_parse_dump(bio_out, p, length, indent, dump)) {
291                ERR_print_errors(bio_err);
292                goto end;
293            }
294        }
295    }
296    ret = 0;
297 end:
298    BIO_free(derout);
299    BIO_free(in);
300    BIO_free(b64);
301    if (ret != 0)
302        ERR_print_errors(bio_err);
303    BUF_MEM_free(buf);
304    OPENSSL_free(name);
305    OPENSSL_free(header);
306    ASN1_TYPE_free(at);
307    sk_OPENSSL_STRING_free(osk);
308    return ret;
309}
310
311static int do_generate(char *genstr, const char *genconf, BUF_MEM *buf)
312{
313    CONF *cnf = NULL;
314    int len;
315    unsigned char *p;
316    ASN1_TYPE *atyp = NULL;
317
318    if (genconf != NULL) {
319        if ((cnf = app_load_config(genconf)) == NULL)
320            goto err;
321        if (genstr == NULL)
322            genstr = NCONF_get_string(cnf, "default", "asn1");
323        if (genstr == NULL) {
324            BIO_printf(bio_err, "Can't find 'asn1' in '%s'\n", genconf);
325            goto err;
326        }
327    }
328
329    atyp = ASN1_generate_nconf(genstr, cnf);
330    NCONF_free(cnf);
331    cnf = NULL;
332
333    if (atyp == NULL)
334        return -1;
335
336    len = i2d_ASN1_TYPE(atyp, NULL);
337
338    if (len <= 0)
339        goto err;
340
341    if (!BUF_MEM_grow(buf, len))
342        goto err;
343
344    p = (unsigned char *)buf->data;
345
346    i2d_ASN1_TYPE(atyp, &p);
347
348    ASN1_TYPE_free(atyp);
349    return len;
350
351 err:
352    NCONF_free(cnf);
353    ASN1_TYPE_free(atyp);
354    return -1;
355}
356