Coverage Report

Created: 2024-11-21 07:03

/src/openssl/crypto/x509/v3_ncons.c
Line
Count
Source (jump to first uncovered line)
1
/*
2
 * Copyright 2003-2024 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 "internal/cryptlib.h"
11
#include "internal/numbers.h"
12
#include "internal/safe_math.h"
13
#include <stdio.h>
14
#include "crypto/asn1.h"
15
#include <openssl/asn1t.h>
16
#include <openssl/conf.h>
17
#include <openssl/x509v3.h>
18
#include <openssl/bn.h>
19
20
#include "crypto/x509.h"
21
#include "crypto/punycode.h"
22
#include "ext_dat.h"
23
24
OSSL_SAFE_MATH_SIGNED(int, int)
25
26
static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
27
                                  X509V3_CTX *ctx,
28
                                  STACK_OF(CONF_VALUE) *nval);
29
static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a,
30
                                BIO *bp, int ind);
31
static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
32
                                   STACK_OF(GENERAL_SUBTREE) *trees, BIO *bp,
33
                                   int ind, const char *name);
34
static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip);
35
36
static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc);
37
static int nc_match_single(int effective_type, GENERAL_NAME *gen,
38
                           GENERAL_NAME *base);
39
static int nc_dn(const X509_NAME *sub, const X509_NAME *nm);
40
static int nc_dns(ASN1_IA5STRING *sub, ASN1_IA5STRING *dns);
41
static int nc_email(ASN1_IA5STRING *sub, ASN1_IA5STRING *eml);
42
static int nc_email_eai(ASN1_TYPE *emltype, ASN1_IA5STRING *base);
43
static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base);
44
static int nc_ip(ASN1_OCTET_STRING *ip, ASN1_OCTET_STRING *base);
45
46
const X509V3_EXT_METHOD ossl_v3_name_constraints = {
47
    NID_name_constraints, 0,
48
    ASN1_ITEM_ref(NAME_CONSTRAINTS),
49
    0, 0, 0, 0,
50
    0, 0,
51
    0, v2i_NAME_CONSTRAINTS,
52
    i2r_NAME_CONSTRAINTS, 0,
53
    NULL
54
};
55
56
const X509V3_EXT_METHOD ossl_v3_holder_name_constraints = {
57
    NID_holder_name_constraints, 0,
58
    ASN1_ITEM_ref(NAME_CONSTRAINTS),
59
    0, 0, 0, 0,
60
    0, 0,
61
    0, v2i_NAME_CONSTRAINTS,
62
    i2r_NAME_CONSTRAINTS, 0,
63
    NULL
64
};
65
66
const X509V3_EXT_METHOD ossl_v3_delegated_name_constraints = {
67
    NID_delegated_name_constraints, 0,
68
    ASN1_ITEM_ref(NAME_CONSTRAINTS),
69
    0, 0, 0, 0,
70
    0, 0,
71
    0, v2i_NAME_CONSTRAINTS,
72
    i2r_NAME_CONSTRAINTS, 0,
73
    NULL
74
};
75
76
ASN1_SEQUENCE(GENERAL_SUBTREE) = {
77
        ASN1_SIMPLE(GENERAL_SUBTREE, base, GENERAL_NAME),
78
        ASN1_IMP_OPT(GENERAL_SUBTREE, minimum, ASN1_INTEGER, 0),
79
        ASN1_IMP_OPT(GENERAL_SUBTREE, maximum, ASN1_INTEGER, 1)
80
} ASN1_SEQUENCE_END(GENERAL_SUBTREE)
81
82
ASN1_SEQUENCE(NAME_CONSTRAINTS) = {
83
        ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, permittedSubtrees,
84
                                                        GENERAL_SUBTREE, 0),
85
        ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, excludedSubtrees,
86
                                                        GENERAL_SUBTREE, 1),
87
} ASN1_SEQUENCE_END(NAME_CONSTRAINTS)
88
89
90
IMPLEMENT_ASN1_ALLOC_FUNCTIONS(GENERAL_SUBTREE)
91
IMPLEMENT_ASN1_ALLOC_FUNCTIONS(NAME_CONSTRAINTS)
92
93
94
#define IA5_OFFSET_LEN(ia5base, offset) \
95
0
    ((ia5base)->length - ((unsigned char *)(offset) - (ia5base)->data))
96
97
/* Like memchr but for ASN1_IA5STRING. Additionally you can specify the
98
 * starting point to search from
99
 */
100
0
# define ia5memchr(str, start, c) memchr(start, c, IA5_OFFSET_LEN(str, start))
101
102
/* Like memrrchr but for ASN1_IA5STRING */
103
static char *ia5memrchr(ASN1_IA5STRING *str, int c)
104
0
{
105
0
    int i;
106
107
0
    for (i = str->length; i > 0 && str->data[i - 1] != c; i--);
108
109
0
    if (i == 0)
110
0
        return NULL;
111
112
0
    return (char *)&str->data[i - 1];
113
0
}
114
115
/*
116
 * We cannot use strncasecmp here because that applies locale specific rules. It
117
 * also doesn't work with ASN1_STRINGs that may have embedded NUL characters.
118
 * For example in Turkish 'I' is not the uppercase character for 'i'. We need to
119
 * do a simple ASCII case comparison ignoring the locale (that is why we use
120
 * numeric constants below).
121
 */
122
static int ia5ncasecmp(const char *s1, const char *s2, size_t n)
123
0
{
124
0
    for (; n > 0; n--, s1++, s2++) {
125
0
        if (*s1 != *s2) {
126
0
            unsigned char c1 = (unsigned char)*s1, c2 = (unsigned char)*s2;
127
128
            /* Convert to lower case */
129
0
            if (c1 >= 0x41 /* A */ && c1 <= 0x5A /* Z */)
130
0
                c1 += 0x20;
131
0
            if (c2 >= 0x41 /* A */ && c2 <= 0x5A /* Z */)
132
0
                c2 += 0x20;
133
134
0
            if (c1 == c2)
135
0
                continue;
136
137
0
            if (c1 < c2)
138
0
                return -1;
139
140
            /* c1 > c2 */
141
0
            return 1;
142
0
        }
143
0
    }
144
145
0
    return 0;
146
0
}
147
148
static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
149
                                  X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval)
150
0
{
151
0
    int i;
152
0
    CONF_VALUE tval, *val;
153
0
    STACK_OF(GENERAL_SUBTREE) **ptree = NULL;
154
0
    NAME_CONSTRAINTS *ncons = NULL;
155
0
    GENERAL_SUBTREE *sub = NULL;
156
157
0
    ncons = NAME_CONSTRAINTS_new();
158
0
    if (ncons == NULL) {
159
0
        ERR_raise(ERR_LIB_X509V3, ERR_R_ASN1_LIB);
160
0
        goto err;
161
0
    }
162
0
    for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
163
0
        val = sk_CONF_VALUE_value(nval, i);
164
0
        if (HAS_PREFIX(val->name, "permitted") && val->name[9]) {
165
0
            ptree = &ncons->permittedSubtrees;
166
0
            tval.name = val->name + 10;
167
0
        } else if (HAS_PREFIX(val->name, "excluded") && val->name[8]) {
168
0
            ptree = &ncons->excludedSubtrees;
169
0
            tval.name = val->name + 9;
170
0
        } else {
171
0
            ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_SYNTAX);
172
0
            goto err;
173
0
        }
174
0
        tval.value = val->value;
175
0
        sub = GENERAL_SUBTREE_new();
176
0
        if (sub == NULL) {
177
0
            ERR_raise(ERR_LIB_X509V3, ERR_R_ASN1_LIB);
178
0
            goto err;
179
0
        }
180
0
        if (!v2i_GENERAL_NAME_ex(sub->base, method, ctx, &tval, 1)) {
181
0
            ERR_raise(ERR_LIB_X509V3, ERR_R_X509V3_LIB);
182
0
            goto err;
183
0
        }
184
0
        if (*ptree == NULL)
185
0
            *ptree = sk_GENERAL_SUBTREE_new_null();
186
0
        if (*ptree == NULL || !sk_GENERAL_SUBTREE_push(*ptree, sub)) {
187
0
            ERR_raise(ERR_LIB_X509V3, ERR_R_CRYPTO_LIB);
188
0
            goto err;
189
0
        }
190
0
        sub = NULL;
191
0
    }
192
193
0
    return ncons;
194
195
0
 err:
196
0
    NAME_CONSTRAINTS_free(ncons);
197
0
    GENERAL_SUBTREE_free(sub);
198
199
0
    return NULL;
200
0
}
201
202
static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a,
203
                                BIO *bp, int ind)
204
0
{
205
0
    NAME_CONSTRAINTS *ncons = a;
206
0
    do_i2r_name_constraints(method, ncons->permittedSubtrees,
207
0
                            bp, ind, "Permitted");
208
0
    if (ncons->permittedSubtrees && ncons->excludedSubtrees)
209
0
        BIO_puts(bp, "\n");
210
0
    do_i2r_name_constraints(method, ncons->excludedSubtrees,
211
0
                            bp, ind, "Excluded");
212
0
    return 1;
213
0
}
214
215
static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
216
                                   STACK_OF(GENERAL_SUBTREE) *trees,
217
                                   BIO *bp, int ind, const char *name)
218
0
{
219
0
    GENERAL_SUBTREE *tree;
220
0
    int i;
221
0
    if (sk_GENERAL_SUBTREE_num(trees) > 0)
222
0
        BIO_printf(bp, "%*s%s:\n", ind, "", name);
223
0
    for (i = 0; i < sk_GENERAL_SUBTREE_num(trees); i++) {
224
0
        if (i > 0)
225
0
            BIO_puts(bp, "\n");
226
0
        tree = sk_GENERAL_SUBTREE_value(trees, i);
227
0
        BIO_printf(bp, "%*s", ind + 2, "");
228
0
        if (tree->base->type == GEN_IPADD)
229
0
            print_nc_ipadd(bp, tree->base->d.ip);
230
0
        else
231
0
            GENERAL_NAME_print(bp, tree->base);
232
0
    }
233
0
    return 1;
234
0
}
235
236
static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip)
237
0
{
238
    /* ip->length should be 8 or 32 and len1 == len2 == 4 or len1 == len2 == 16 */
239
0
    int len1 = ip->length >= 16 ? 16 : ip->length >= 4 ? 4 : ip->length;
240
0
    int len2 = ip->length - len1;
241
0
    char *ip1 = ossl_ipaddr_to_asc(ip->data, len1);
242
0
    char *ip2 = ossl_ipaddr_to_asc(ip->data + len1, len2);
243
0
    int ret = ip1 != NULL && ip2 != NULL
244
0
        && BIO_printf(bp, "IP:%s/%s", ip1, ip2) > 0;
245
246
0
    OPENSSL_free(ip1);
247
0
    OPENSSL_free(ip2);
248
0
    return ret;
249
0
}
250
251
0
#define NAME_CHECK_MAX (1 << 20)
252
253
static int add_lengths(int *out, int a, int b)
254
0
{
255
0
    int err = 0;
256
257
    /* sk_FOO_num(NULL) returns -1 but is effectively 0 when iterating. */
258
0
    if (a < 0)
259
0
        a = 0;
260
0
    if (b < 0)
261
0
        b = 0;
262
263
0
    *out = safe_add_int(a, b, &err);
264
0
    return !err;
265
0
}
266
267
/*-
268
 * Check a certificate conforms to a specified set of constraints.
269
 * Return values:
270
 *  X509_V_OK: All constraints obeyed.
271
 *  X509_V_ERR_PERMITTED_VIOLATION: Permitted subtree violation.
272
 *  X509_V_ERR_EXCLUDED_VIOLATION: Excluded subtree violation.
273
 *  X509_V_ERR_SUBTREE_MINMAX: Min or max values present and matching type.
274
 *  X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE:  Unsupported constraint type.
275
 *  X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX: bad unsupported constraint syntax.
276
 *  X509_V_ERR_UNSUPPORTED_NAME_SYNTAX: bad or unsupported syntax of name
277
 */
278
279
int NAME_CONSTRAINTS_check(X509 *x, NAME_CONSTRAINTS *nc)
280
0
{
281
0
    int r, i, name_count, constraint_count;
282
0
    X509_NAME *nm;
283
284
0
    nm = X509_get_subject_name(x);
285
286
    /*
287
     * Guard against certificates with an excessive number of names or
288
     * constraints causing a computationally expensive name constraints check.
289
     */
290
0
    if (!add_lengths(&name_count, X509_NAME_entry_count(nm),
291
0
                     sk_GENERAL_NAME_num(x->altname))
292
0
        || !add_lengths(&constraint_count,
293
0
                        sk_GENERAL_SUBTREE_num(nc->permittedSubtrees),
294
0
                        sk_GENERAL_SUBTREE_num(nc->excludedSubtrees))
295
0
        || (name_count > 0 && constraint_count > NAME_CHECK_MAX / name_count))
296
0
        return X509_V_ERR_UNSPECIFIED;
297
298
0
    if (X509_NAME_entry_count(nm) > 0) {
299
0
        GENERAL_NAME gntmp;
300
0
        gntmp.type = GEN_DIRNAME;
301
0
        gntmp.d.directoryName = nm;
302
303
0
        r = nc_match(&gntmp, nc);
304
305
0
        if (r != X509_V_OK)
306
0
            return r;
307
308
0
        gntmp.type = GEN_EMAIL;
309
310
        /* Process any email address attributes in subject name */
311
312
0
        for (i = -1;;) {
313
0
            const X509_NAME_ENTRY *ne;
314
315
0
            i = X509_NAME_get_index_by_NID(nm, NID_pkcs9_emailAddress, i);
316
0
            if (i == -1)
317
0
                break;
318
0
            ne = X509_NAME_get_entry(nm, i);
319
0
            gntmp.d.rfc822Name = X509_NAME_ENTRY_get_data(ne);
320
0
            if (gntmp.d.rfc822Name->type != V_ASN1_IA5STRING)
321
0
                return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
322
323
0
            r = nc_match(&gntmp, nc);
324
325
0
            if (r != X509_V_OK)
326
0
                return r;
327
0
        }
328
329
0
    }
330
331
0
    for (i = 0; i < sk_GENERAL_NAME_num(x->altname); i++) {
332
0
        GENERAL_NAME *gen = sk_GENERAL_NAME_value(x->altname, i);
333
0
        r = nc_match(gen, nc);
334
0
        if (r != X509_V_OK)
335
0
            return r;
336
0
    }
337
338
0
    return X509_V_OK;
339
340
0
}
341
342
static int cn2dnsid(ASN1_STRING *cn, unsigned char **dnsid, size_t *idlen)
343
0
{
344
0
    int utf8_length;
345
0
    unsigned char *utf8_value;
346
0
    int i;
347
0
    int isdnsname = 0;
348
349
    /* Don't leave outputs uninitialized */
350
0
    *dnsid = NULL;
351
0
    *idlen = 0;
352
353
    /*-
354
     * Per RFC 6125, DNS-IDs representing internationalized domain names appear
355
     * in certificates in A-label encoded form:
356
     *
357
     *   https://tools.ietf.org/html/rfc6125#section-6.4.2
358
     *
359
     * The same applies to CNs which are intended to represent DNS names.
360
     * However, while in the SAN DNS-IDs are IA5Strings, as CNs they may be
361
     * needlessly encoded in 16-bit Unicode.  We perform a conversion to UTF-8
362
     * to ensure that we get an ASCII representation of any CNs that are
363
     * representable as ASCII, but just not encoded as ASCII.  The UTF-8 form
364
     * may contain some non-ASCII octets, and that's fine, such CNs are not
365
     * valid legacy DNS names.
366
     *
367
     * Note, 'int' is the return type of ASN1_STRING_to_UTF8() so that's what
368
     * we must use for 'utf8_length'.
369
     */
370
0
    if ((utf8_length = ASN1_STRING_to_UTF8(&utf8_value, cn)) < 0)
371
0
        return X509_V_ERR_OUT_OF_MEM;
372
373
    /*
374
     * Some certificates have had names that include a *trailing* NUL byte.
375
     * Remove these harmless NUL characters. They would otherwise yield false
376
     * alarms with the following embedded NUL check.
377
     */
378
0
    while (utf8_length > 0 && utf8_value[utf8_length - 1] == '\0')
379
0
        --utf8_length;
380
381
    /* Reject *embedded* NULs */
382
0
    if (memchr(utf8_value, 0, utf8_length) != NULL) {
383
0
        OPENSSL_free(utf8_value);
384
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
385
0
    }
386
387
    /*
388
     * XXX: Deviation from strict DNS name syntax, also check names with '_'
389
     * Check DNS name syntax, any '-' or '.' must be internal,
390
     * and on either side of each '.' we can't have a '-' or '.'.
391
     *
392
     * If the name has just one label, we don't consider it a DNS name.  This
393
     * means that "CN=sometld" cannot be precluded by DNS name constraints, but
394
     * that is not a problem.
395
     */
396
0
    for (i = 0; i < utf8_length; ++i) {
397
0
        unsigned char c = utf8_value[i];
398
399
0
        if ((c >= 'a' && c <= 'z')
400
0
            || (c >= 'A' && c <= 'Z')
401
0
            || (c >= '0' && c <= '9')
402
0
            || c == '_')
403
0
            continue;
404
405
        /* Dot and hyphen cannot be first or last. */
406
0
        if (i > 0 && i < utf8_length - 1) {
407
0
            if (c == '-')
408
0
                continue;
409
            /*
410
             * Next to a dot the preceding and following characters must not be
411
             * another dot or a hyphen.  Otherwise, record that the name is
412
             * plausible, since it has two or more labels.
413
             */
414
0
            if (c == '.'
415
0
                && utf8_value[i + 1] != '.'
416
0
                && utf8_value[i - 1] != '-'
417
0
                && utf8_value[i + 1] != '-') {
418
0
                isdnsname = 1;
419
0
                continue;
420
0
            }
421
0
        }
422
0
        isdnsname = 0;
423
0
        break;
424
0
    }
425
426
0
    if (isdnsname) {
427
0
        *dnsid = utf8_value;
428
0
        *idlen = (size_t)utf8_length;
429
0
        return X509_V_OK;
430
0
    }
431
0
    OPENSSL_free(utf8_value);
432
0
    return X509_V_OK;
433
0
}
434
435
/*
436
 * Check CN against DNS-ID name constraints.
437
 */
438
int NAME_CONSTRAINTS_check_CN(X509 *x, NAME_CONSTRAINTS *nc)
439
0
{
440
0
    int r, i;
441
0
    const X509_NAME *nm = X509_get_subject_name(x);
442
0
    ASN1_STRING stmp;
443
0
    GENERAL_NAME gntmp;
444
445
0
    stmp.flags = 0;
446
0
    stmp.type = V_ASN1_IA5STRING;
447
0
    gntmp.type = GEN_DNS;
448
0
    gntmp.d.dNSName = &stmp;
449
450
    /* Process any commonName attributes in subject name */
451
452
0
    for (i = -1;;) {
453
0
        X509_NAME_ENTRY *ne;
454
0
        ASN1_STRING *cn;
455
0
        unsigned char *idval;
456
0
        size_t idlen;
457
458
0
        i = X509_NAME_get_index_by_NID(nm, NID_commonName, i);
459
0
        if (i == -1)
460
0
            break;
461
0
        ne = X509_NAME_get_entry(nm, i);
462
0
        cn = X509_NAME_ENTRY_get_data(ne);
463
464
        /* Only process attributes that look like hostnames */
465
0
        if ((r = cn2dnsid(cn, &idval, &idlen)) != X509_V_OK)
466
0
            return r;
467
0
        if (idlen == 0)
468
0
            continue;
469
470
0
        stmp.length = idlen;
471
0
        stmp.data = idval;
472
0
        r = nc_match(&gntmp, nc);
473
0
        OPENSSL_free(idval);
474
0
        if (r != X509_V_OK)
475
0
            return r;
476
0
    }
477
0
    return X509_V_OK;
478
0
}
479
480
/*
481
 * Return nonzero if the GeneralSubtree has valid 'minimum' field
482
 * (must be absent or 0) and valid 'maximum' field (must be absent).
483
 */
484
0
static int nc_minmax_valid(GENERAL_SUBTREE *sub) {
485
0
    BIGNUM *bn = NULL;
486
0
    int ok = 1;
487
488
0
    if (sub->maximum)
489
0
        ok = 0;
490
491
0
    if (sub->minimum) {
492
0
        bn = ASN1_INTEGER_to_BN(sub->minimum, NULL);
493
0
        if (bn == NULL || !BN_is_zero(bn))
494
0
            ok = 0;
495
0
        BN_free(bn);
496
0
    }
497
498
0
    return ok;
499
0
}
500
501
static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc)
502
0
{
503
0
    GENERAL_SUBTREE *sub;
504
0
    int i, r, match = 0;
505
0
    int effective_type = gen->type;
506
507
    /*
508
     * We need to compare not gen->type field but an "effective" type because
509
     * the otherName field may contain EAI email address treated specially
510
     * according to RFC 8398, section 6
511
     */
512
0
    if (effective_type == GEN_OTHERNAME &&
513
0
        (OBJ_obj2nid(gen->d.otherName->type_id) == NID_id_on_SmtpUTF8Mailbox)) {
514
0
        effective_type = GEN_EMAIL;
515
0
    }
516
517
    /*
518
     * Permitted subtrees: if any subtrees exist of matching the type at
519
     * least one subtree must match.
520
     */
521
522
0
    for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->permittedSubtrees); i++) {
523
0
        sub = sk_GENERAL_SUBTREE_value(nc->permittedSubtrees, i);
524
0
        if (effective_type != sub->base->type
525
0
            || (effective_type == GEN_OTHERNAME &&
526
0
                OBJ_cmp(gen->d.otherName->type_id,
527
0
                        sub->base->d.otherName->type_id) != 0))
528
0
            continue;
529
0
        if (!nc_minmax_valid(sub))
530
0
            return X509_V_ERR_SUBTREE_MINMAX;
531
        /* If we already have a match don't bother trying any more */
532
0
        if (match == 2)
533
0
            continue;
534
0
        if (match == 0)
535
0
            match = 1;
536
0
        r = nc_match_single(effective_type, gen, sub->base);
537
0
        if (r == X509_V_OK)
538
0
            match = 2;
539
0
        else if (r != X509_V_ERR_PERMITTED_VIOLATION)
540
0
            return r;
541
0
    }
542
543
0
    if (match == 1)
544
0
        return X509_V_ERR_PERMITTED_VIOLATION;
545
546
    /* Excluded subtrees: must not match any of these */
547
548
0
    for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->excludedSubtrees); i++) {
549
0
        sub = sk_GENERAL_SUBTREE_value(nc->excludedSubtrees, i);
550
0
        if (effective_type != sub->base->type
551
0
            || (effective_type == GEN_OTHERNAME &&
552
0
                OBJ_cmp(gen->d.otherName->type_id,
553
0
                        sub->base->d.otherName->type_id) != 0))
554
0
            continue;
555
0
        if (!nc_minmax_valid(sub))
556
0
            return X509_V_ERR_SUBTREE_MINMAX;
557
558
0
        r = nc_match_single(effective_type, gen, sub->base);
559
0
        if (r == X509_V_OK)
560
0
            return X509_V_ERR_EXCLUDED_VIOLATION;
561
0
        else if (r != X509_V_ERR_PERMITTED_VIOLATION)
562
0
            return r;
563
564
0
    }
565
566
0
    return X509_V_OK;
567
568
0
}
569
570
static int nc_match_single(int effective_type, GENERAL_NAME *gen,
571
                           GENERAL_NAME *base)
572
0
{
573
0
    switch (gen->type) {
574
0
    case GEN_OTHERNAME:
575
0
        switch (effective_type) {
576
0
        case GEN_EMAIL:
577
            /*
578
             * We are here only when we have SmtpUTF8 name,
579
             * so we match the value of othername with base->d.rfc822Name
580
             */
581
0
            return nc_email_eai(gen->d.otherName->value, base->d.rfc822Name);
582
583
0
        default:
584
0
            return X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE;
585
0
        }
586
587
0
    case GEN_DIRNAME:
588
0
        return nc_dn(gen->d.directoryName, base->d.directoryName);
589
590
0
    case GEN_DNS:
591
0
        return nc_dns(gen->d.dNSName, base->d.dNSName);
592
593
0
    case GEN_EMAIL:
594
0
        return nc_email(gen->d.rfc822Name, base->d.rfc822Name);
595
596
0
    case GEN_URI:
597
0
        return nc_uri(gen->d.uniformResourceIdentifier,
598
0
                      base->d.uniformResourceIdentifier);
599
600
0
    case GEN_IPADD:
601
0
        return nc_ip(gen->d.iPAddress, base->d.iPAddress);
602
603
0
    default:
604
0
        return X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE;
605
0
    }
606
607
0
}
608
609
/*
610
 * directoryName name constraint matching. The canonical encoding of
611
 * X509_NAME makes this comparison easy. It is matched if the subtree is a
612
 * subset of the name.
613
 */
614
615
static int nc_dn(const X509_NAME *nm, const X509_NAME *base)
616
0
{
617
    /* Ensure canonical encodings are up to date.  */
618
0
    if (nm->modified && i2d_X509_NAME(nm, NULL) < 0)
619
0
        return X509_V_ERR_OUT_OF_MEM;
620
0
    if (base->modified && i2d_X509_NAME(base, NULL) < 0)
621
0
        return X509_V_ERR_OUT_OF_MEM;
622
0
    if (base->canon_enclen > nm->canon_enclen)
623
0
        return X509_V_ERR_PERMITTED_VIOLATION;
624
0
    if (memcmp(base->canon_enc, nm->canon_enc, base->canon_enclen))
625
0
        return X509_V_ERR_PERMITTED_VIOLATION;
626
0
    return X509_V_OK;
627
0
}
628
629
static int nc_dns(ASN1_IA5STRING *dns, ASN1_IA5STRING *base)
630
0
{
631
0
    char *baseptr = (char *)base->data;
632
0
    char *dnsptr = (char *)dns->data;
633
634
    /* Empty matches everything */
635
0
    if (base->length == 0)
636
0
        return X509_V_OK;
637
638
0
    if (dns->length < base->length)
639
0
        return X509_V_ERR_PERMITTED_VIOLATION;
640
641
    /*
642
     * Otherwise can add zero or more components on the left so compare RHS
643
     * and if dns is longer and expect '.' as preceding character.
644
     */
645
0
    if (dns->length > base->length) {
646
0
        dnsptr += dns->length - base->length;
647
0
        if (*baseptr != '.' && dnsptr[-1] != '.')
648
0
            return X509_V_ERR_PERMITTED_VIOLATION;
649
0
    }
650
651
0
    if (ia5ncasecmp(baseptr, dnsptr, base->length))
652
0
        return X509_V_ERR_PERMITTED_VIOLATION;
653
654
0
    return X509_V_OK;
655
656
0
}
657
658
/*
659
 * This function implements comparison between ASCII/U-label in emltype
660
 * and A-label in base according to RFC 8398, section 6.
661
 * Convert base to U-label and ASCII-parts of domain names, for base
662
 * Octet-to-octet comparison of `emltype` and `base` hostname parts
663
 * (ASCII-parts should be compared in case-insensitive manner)
664
 */
665
static int nc_email_eai(ASN1_TYPE *emltype, ASN1_IA5STRING *base)
666
0
{
667
0
    ASN1_UTF8STRING *eml;
668
0
    char *baseptr = NULL;
669
0
    const char *emlptr;
670
0
    const char *emlat;
671
0
    char ulabel[256];
672
0
    size_t size = sizeof(ulabel);
673
0
    int ret = X509_V_OK;
674
0
    size_t emlhostlen;
675
676
    /* We do not accept embedded NUL characters */
677
0
    if (base->length > 0 && memchr(base->data, 0, base->length) != NULL)
678
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
679
680
    /* 'base' may not be NUL terminated. Create a copy that is */
681
0
    baseptr = OPENSSL_strndup((char *)base->data, base->length);
682
0
    if (baseptr == NULL)
683
0
        return X509_V_ERR_OUT_OF_MEM;
684
685
0
    if (emltype->type != V_ASN1_UTF8STRING) {
686
0
        ret = X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
687
0
        goto end;
688
0
    }
689
690
0
    eml = emltype->value.utf8string;
691
0
    emlptr = (char *)eml->data;
692
0
    emlat = ia5memrchr(eml, '@');
693
694
0
    if (emlat == NULL) {
695
0
        ret = X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
696
0
        goto end;
697
0
    }
698
699
    /* Special case: initial '.' is RHS match */
700
0
    if (*baseptr == '.') {
701
0
        ulabel[0] = '.';
702
0
        if (ossl_a2ulabel(baseptr, ulabel + 1, size - 1) <= 0) {
703
0
            ret = X509_V_ERR_UNSPECIFIED;
704
0
            goto end;
705
0
        }
706
707
0
        if ((size_t)eml->length > strlen(ulabel)) {
708
0
            emlptr += eml->length - strlen(ulabel);
709
            /* X509_V_OK */
710
0
            if (ia5ncasecmp(ulabel, emlptr, strlen(ulabel)) == 0)
711
0
                goto end;
712
0
        }
713
0
        ret = X509_V_ERR_PERMITTED_VIOLATION;
714
0
        goto end;
715
0
    }
716
717
0
    if (ossl_a2ulabel(baseptr, ulabel, size) <= 0) {
718
0
        ret = X509_V_ERR_UNSPECIFIED;
719
0
        goto end;
720
0
    }
721
    /* Just have hostname left to match: case insensitive */
722
0
    emlptr = emlat + 1;
723
0
    emlhostlen = IA5_OFFSET_LEN(eml, emlptr);
724
0
    if (emlhostlen != strlen(ulabel)
725
0
            || ia5ncasecmp(ulabel, emlptr, emlhostlen) != 0) {
726
0
        ret = X509_V_ERR_PERMITTED_VIOLATION;
727
0
        goto end;
728
0
    }
729
730
0
 end:
731
0
    OPENSSL_free(baseptr);
732
0
    return ret;
733
0
}
734
735
static int nc_email(ASN1_IA5STRING *eml, ASN1_IA5STRING *base)
736
0
{
737
0
    const char *baseptr = (char *)base->data;
738
0
    const char *emlptr = (char *)eml->data;
739
0
    const char *baseat = ia5memrchr(base, '@');
740
0
    const char *emlat = ia5memrchr(eml, '@');
741
0
    size_t basehostlen, emlhostlen;
742
743
0
    if (!emlat)
744
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
745
    /* Special case: initial '.' is RHS match */
746
0
    if (!baseat && base->length > 0 && (*baseptr == '.')) {
747
0
        if (eml->length > base->length) {
748
0
            emlptr += eml->length - base->length;
749
0
            if (ia5ncasecmp(baseptr, emlptr, base->length) == 0)
750
0
                return X509_V_OK;
751
0
        }
752
0
        return X509_V_ERR_PERMITTED_VIOLATION;
753
0
    }
754
755
    /* If we have anything before '@' match local part */
756
757
0
    if (baseat) {
758
0
        if (baseat != baseptr) {
759
0
            if ((baseat - baseptr) != (emlat - emlptr))
760
0
                return X509_V_ERR_PERMITTED_VIOLATION;
761
0
            if (memchr(baseptr, 0, baseat - baseptr) ||
762
0
                memchr(emlptr, 0, emlat - emlptr))
763
0
                return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
764
            /* Case sensitive match of local part */
765
0
            if (strncmp(baseptr, emlptr, emlat - emlptr))
766
0
                return X509_V_ERR_PERMITTED_VIOLATION;
767
0
        }
768
        /* Position base after '@' */
769
0
        baseptr = baseat + 1;
770
0
    }
771
0
    emlptr = emlat + 1;
772
0
    basehostlen = IA5_OFFSET_LEN(base, baseptr);
773
0
    emlhostlen = IA5_OFFSET_LEN(eml, emlptr);
774
    /* Just have hostname left to match: case insensitive */
775
0
    if (basehostlen != emlhostlen || ia5ncasecmp(baseptr, emlptr, emlhostlen))
776
0
        return X509_V_ERR_PERMITTED_VIOLATION;
777
778
0
    return X509_V_OK;
779
780
0
}
781
782
static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base)
783
0
{
784
0
    const char *baseptr = (char *)base->data;
785
0
    const char *hostptr = (char *)uri->data;
786
0
    const char *p = ia5memchr(uri, (char *)uri->data, ':');
787
0
    int hostlen;
788
789
    /* Check for foo:// and skip past it */
790
0
    if (p == NULL
791
0
            || IA5_OFFSET_LEN(uri, p) < 3
792
0
            || p[1] != '/'
793
0
            || p[2] != '/')
794
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
795
0
    hostptr = p + 3;
796
797
    /* Determine length of hostname part of URI */
798
799
    /* Look for a port indicator as end of hostname first */
800
801
0
    p = ia5memchr(uri, hostptr, ':');
802
    /* Otherwise look for trailing slash */
803
0
    if (p == NULL)
804
0
        p = ia5memchr(uri, hostptr, '/');
805
806
0
    if (p == NULL)
807
0
        hostlen = IA5_OFFSET_LEN(uri, hostptr);
808
0
    else
809
0
        hostlen = p - hostptr;
810
811
0
    if (hostlen == 0)
812
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
813
814
    /* Special case: initial '.' is RHS match */
815
0
    if (base->length > 0 && *baseptr == '.') {
816
0
        if (hostlen > base->length) {
817
0
            p = hostptr + hostlen - base->length;
818
0
            if (ia5ncasecmp(p, baseptr, base->length) == 0)
819
0
                return X509_V_OK;
820
0
        }
821
0
        return X509_V_ERR_PERMITTED_VIOLATION;
822
0
    }
823
824
0
    if ((base->length != (int)hostlen)
825
0
        || ia5ncasecmp(hostptr, baseptr, hostlen))
826
0
        return X509_V_ERR_PERMITTED_VIOLATION;
827
828
0
    return X509_V_OK;
829
830
0
}
831
832
static int nc_ip(ASN1_OCTET_STRING *ip, ASN1_OCTET_STRING *base)
833
0
{
834
0
    int hostlen, baselen, i;
835
0
    unsigned char *hostptr, *baseptr, *maskptr;
836
0
    hostptr = ip->data;
837
0
    hostlen = ip->length;
838
0
    baseptr = base->data;
839
0
    baselen = base->length;
840
841
    /* Invalid if not IPv4 or IPv6 */
842
0
    if (!((hostlen == 4) || (hostlen == 16)))
843
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
844
0
    if (!((baselen == 8) || (baselen == 32)))
845
0
        return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
846
847
    /* Do not match IPv4 with IPv6 */
848
0
    if (hostlen * 2 != baselen)
849
0
        return X509_V_ERR_PERMITTED_VIOLATION;
850
851
0
    maskptr = base->data + hostlen;
852
853
    /* Considering possible not aligned base ipAddress */
854
    /* Not checking for wrong mask definition: i.e.: 255.0.255.0 */
855
0
    for (i = 0; i < hostlen; i++)
856
0
        if ((hostptr[i] & maskptr[i]) != (baseptr[i] & maskptr[i]))
857
0
            return X509_V_ERR_PERMITTED_VIOLATION;
858
859
0
    return X509_V_OK;
860
861
0
}