1/*
2 * Copyright 2006-2016 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/*
11 * Implementation of RFC 3779 section 2.2.
12 */
13
14#include <stdio.h>
15#include <stdlib.h>
16
17#include "internal/cryptlib.h"
18#include <openssl/conf.h>
19#include <openssl/asn1.h>
20#include <openssl/asn1t.h>
21#include <openssl/buffer.h>
22#include <openssl/x509v3.h>
23#include "crypto/x509.h"
24#include "ext_dat.h"
25
26#ifndef OPENSSL_NO_RFC3779
27
28/*
29 * OpenSSL ASN.1 template translation of RFC 3779 2.2.3.
30 */
31
32ASN1_SEQUENCE(IPAddressRange) = {
33 ASN1_SIMPLE(IPAddressRange, min, ASN1_BIT_STRING),
34 ASN1_SIMPLE(IPAddressRange, max, ASN1_BIT_STRING)
35} ASN1_SEQUENCE_END(IPAddressRange)
36
37ASN1_CHOICE(IPAddressOrRange) = {
38 ASN1_SIMPLE(IPAddressOrRange, u.addressPrefix, ASN1_BIT_STRING),
39 ASN1_SIMPLE(IPAddressOrRange, u.addressRange, IPAddressRange)
40} ASN1_CHOICE_END(IPAddressOrRange)
41
42ASN1_CHOICE(IPAddressChoice) = {
43 ASN1_SIMPLE(IPAddressChoice, u.inherit, ASN1_NULL),
44 ASN1_SEQUENCE_OF(IPAddressChoice, u.addressesOrRanges, IPAddressOrRange)
45} ASN1_CHOICE_END(IPAddressChoice)
46
47ASN1_SEQUENCE(IPAddressFamily) = {
48 ASN1_SIMPLE(IPAddressFamily, addressFamily, ASN1_OCTET_STRING),
49 ASN1_SIMPLE(IPAddressFamily, ipAddressChoice, IPAddressChoice)
50} ASN1_SEQUENCE_END(IPAddressFamily)
51
52ASN1_ITEM_TEMPLATE(IPAddrBlocks) =
53 ASN1_EX_TEMPLATE_TYPE(ASN1_TFLG_SEQUENCE_OF, 0,
54 IPAddrBlocks, IPAddressFamily)
55static_ASN1_ITEM_TEMPLATE_END(IPAddrBlocks)
56
57IMPLEMENT_ASN1_FUNCTIONS(IPAddressRange)
58IMPLEMENT_ASN1_FUNCTIONS(IPAddressOrRange)
59IMPLEMENT_ASN1_FUNCTIONS(IPAddressChoice)
60IMPLEMENT_ASN1_FUNCTIONS(IPAddressFamily)
61
62/*
63 * How much buffer space do we need for a raw address?
64 */
65#define ADDR_RAW_BUF_LEN 16
66
67/*
68 * What's the address length associated with this AFI?
69 */
70static int length_from_afi(const unsigned afi)
71{
72 switch (afi) {
73 case IANA_AFI_IPV4:
74 return 4;
75 case IANA_AFI_IPV6:
76 return 16;
77 default:
78 return 0;
79 }
80}
81
82/*
83 * Extract the AFI from an IPAddressFamily.
84 */
85unsigned int X509v3_addr_get_afi(const IPAddressFamily *f)
86{
87 if (f == NULL
88 || f->addressFamily == NULL
89 || f->addressFamily->data == NULL
90 || f->addressFamily->length < 2)
91 return 0;
92 return (f->addressFamily->data[0] << 8) | f->addressFamily->data[1];
93}
94
95/*
96 * Expand the bitstring form of an address into a raw byte array.
97 * At the moment this is coded for simplicity, not speed.
98 */
99static int addr_expand(unsigned char *addr,
100 const ASN1_BIT_STRING *bs,
101 const int length, const unsigned char fill)
102{
103 if (bs->length < 0 || bs->length > length)
104 return 0;
105 if (bs->length > 0) {
106 memcpy(addr, bs->data, bs->length);
107 if ((bs->flags & 7) != 0) {
108 unsigned char mask = 0xFF >> (8 - (bs->flags & 7));
109 if (fill == 0)
110 addr[bs->length - 1] &= ~mask;
111 else
112 addr[bs->length - 1] |= mask;
113 }
114 }
115 memset(addr + bs->length, fill, length - bs->length);
116 return 1;
117}
118
119/*
120 * Extract the prefix length from a bitstring.
121 */
122#define addr_prefixlen(bs) ((int) ((bs)->length * 8 - ((bs)->flags & 7)))
123
124/*
125 * i2r handler for one address bitstring.
126 */
127static int i2r_address(BIO *out,
128 const unsigned afi,
129 const unsigned char fill, const ASN1_BIT_STRING *bs)
130{
131 unsigned char addr[ADDR_RAW_BUF_LEN];
132 int i, n;
133
134 if (bs->length < 0)
135 return 0;
136 switch (afi) {
137 case IANA_AFI_IPV4:
138 if (!addr_expand(addr, bs, 4, fill))
139 return 0;
140 BIO_printf(out, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
141 break;
142 case IANA_AFI_IPV6:
143 if (!addr_expand(addr, bs, 16, fill))
144 return 0;
145 for (n = 16; n > 1 && addr[n - 1] == 0x00 && addr[n - 2] == 0x00;
146 n -= 2) ;
147 for (i = 0; i < n; i += 2)
148 BIO_printf(out, "%x%s", (addr[i] << 8) | addr[i + 1],
149 (i < 14 ? ":" : ""));
150 if (i < 16)
151 BIO_puts(out, ":");
152 if (i == 0)
153 BIO_puts(out, ":");
154 break;
155 default:
156 for (i = 0; i < bs->length; i++)
157 BIO_printf(out, "%s%02x", (i > 0 ? ":" : ""), bs->data[i]);
158 BIO_printf(out, "[%d]", (int)(bs->flags & 7));
159 break;
160 }
161 return 1;
162}
163
164/*
165 * i2r handler for a sequence of addresses and ranges.
166 */
167static int i2r_IPAddressOrRanges(BIO *out,
168 const int indent,
169 const IPAddressOrRanges *aors,
170 const unsigned afi)
171{
172 int i;
173 for (i = 0; i < sk_IPAddressOrRange_num(aors); i++) {
174 const IPAddressOrRange *aor = sk_IPAddressOrRange_value(aors, i);
175 BIO_printf(out, "%*s", indent, "");
176 switch (aor->type) {
177 case IPAddressOrRange_addressPrefix:
178 if (!i2r_address(out, afi, 0x00, aor->u.addressPrefix))
179 return 0;
180 BIO_printf(out, "/%d\n", addr_prefixlen(aor->u.addressPrefix));
181 continue;
182 case IPAddressOrRange_addressRange:
183 if (!i2r_address(out, afi, 0x00, aor->u.addressRange->min))
184 return 0;
185 BIO_puts(out, "-");
186 if (!i2r_address(out, afi, 0xFF, aor->u.addressRange->max))
187 return 0;
188 BIO_puts(out, "\n");
189 continue;
190 }
191 }
192 return 1;
193}
194
195/*
196 * i2r handler for an IPAddrBlocks extension.
197 */
198static int i2r_IPAddrBlocks(const X509V3_EXT_METHOD *method,
199 void *ext, BIO *out, int indent)
200{
201 const IPAddrBlocks *addr = ext;
202 int i;
203 for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {
204 IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);
205 const unsigned int afi = X509v3_addr_get_afi(f);
206 switch (afi) {
207 case IANA_AFI_IPV4:
208 BIO_printf(out, "%*sIPv4", indent, "");
209 break;
210 case IANA_AFI_IPV6:
211 BIO_printf(out, "%*sIPv6", indent, "");
212 break;
213 default:
214 BIO_printf(out, "%*sUnknown AFI %u", indent, "", afi);
215 break;
216 }
217 if (f->addressFamily->length > 2) {
218 switch (f->addressFamily->data[2]) {
219 case 1:
220 BIO_puts(out, " (Unicast)");
221 break;
222 case 2:
223 BIO_puts(out, " (Multicast)");
224 break;
225 case 3:
226 BIO_puts(out, " (Unicast/Multicast)");
227 break;
228 case 4:
229 BIO_puts(out, " (MPLS)");
230 break;
231 case 64:
232 BIO_puts(out, " (Tunnel)");
233 break;
234 case 65:
235 BIO_puts(out, " (VPLS)");
236 break;
237 case 66:
238 BIO_puts(out, " (BGP MDT)");
239 break;
240 case 128:
241 BIO_puts(out, " (MPLS-labeled VPN)");
242 break;
243 default:
244 BIO_printf(out, " (Unknown SAFI %u)",
245 (unsigned)f->addressFamily->data[2]);
246 break;
247 }
248 }
249 switch (f->ipAddressChoice->type) {
250 case IPAddressChoice_inherit:
251 BIO_puts(out, ": inherit\n");
252 break;
253 case IPAddressChoice_addressesOrRanges:
254 BIO_puts(out, ":\n");
255 if (!i2r_IPAddressOrRanges(out,
256 indent + 2,
257 f->ipAddressChoice->
258 u.addressesOrRanges, afi))
259 return 0;
260 break;
261 }
262 }
263 return 1;
264}
265
266/*
267 * Sort comparison function for a sequence of IPAddressOrRange
268 * elements.
269 *
270 * There's no sane answer we can give if addr_expand() fails, and an
271 * assertion failure on externally supplied data is seriously uncool,
272 * so we just arbitrarily declare that if given invalid inputs this
273 * function returns -1. If this messes up your preferred sort order
274 * for garbage input, tough noogies.
275 */
276static int IPAddressOrRange_cmp(const IPAddressOrRange *a,
277 const IPAddressOrRange *b, const int length)
278{
279 unsigned char addr_a[ADDR_RAW_BUF_LEN], addr_b[ADDR_RAW_BUF_LEN];
280 int prefixlen_a = 0, prefixlen_b = 0;
281 int r;
282
283 switch (a->type) {
284 case IPAddressOrRange_addressPrefix:
285 if (!addr_expand(addr_a, a->u.addressPrefix, length, 0x00))
286 return -1;
287 prefixlen_a = addr_prefixlen(a->u.addressPrefix);
288 break;
289 case IPAddressOrRange_addressRange:
290 if (!addr_expand(addr_a, a->u.addressRange->min, length, 0x00))
291 return -1;
292 prefixlen_a = length * 8;
293 break;
294 }
295
296 switch (b->type) {
297 case IPAddressOrRange_addressPrefix:
298 if (!addr_expand(addr_b, b->u.addressPrefix, length, 0x00))
299 return -1;
300 prefixlen_b = addr_prefixlen(b->u.addressPrefix);
301 break;
302 case IPAddressOrRange_addressRange:
303 if (!addr_expand(addr_b, b->u.addressRange->min, length, 0x00))
304 return -1;
305 prefixlen_b = length * 8;
306 break;
307 }
308
309 if ((r = memcmp(addr_a, addr_b, length)) != 0)
310 return r;
311 else
312 return prefixlen_a - prefixlen_b;
313}
314
315/*
316 * IPv4-specific closure over IPAddressOrRange_cmp, since sk_sort()
317 * comparison routines are only allowed two arguments.
318 */
319static int v4IPAddressOrRange_cmp(const IPAddressOrRange *const *a,
320 const IPAddressOrRange *const *b)
321{
322 return IPAddressOrRange_cmp(*a, *b, 4);
323}
324
325/*
326 * IPv6-specific closure over IPAddressOrRange_cmp, since sk_sort()
327 * comparison routines are only allowed two arguments.
328 */
329static int v6IPAddressOrRange_cmp(const IPAddressOrRange *const *a,
330 const IPAddressOrRange *const *b)
331{
332 return IPAddressOrRange_cmp(*a, *b, 16);
333}
334
335/*
336 * Calculate whether a range collapses to a prefix.
337 * See last paragraph of RFC 3779 2.2.3.7.
338 */
339static int range_should_be_prefix(const unsigned char *min,
340 const unsigned char *max, const int length)
341{
342 unsigned char mask;
343 int i, j;
344
345 if (memcmp(min, max, length) <= 0)
346 return -1;
347 for (i = 0; i < length && min[i] == max[i]; i++) ;
348 for (j = length - 1; j >= 0 && min[j] == 0x00 && max[j] == 0xFF; j--) ;
349 if (i < j)
350 return -1;
351 if (i > j)
352 return i * 8;
353 mask = min[i] ^ max[i];
354 switch (mask) {
355 case 0x01:
356 j = 7;
357 break;
358 case 0x03:
359 j = 6;
360 break;
361 case 0x07:
362 j = 5;
363 break;
364 case 0x0F:
365 j = 4;
366 break;
367 case 0x1F:
368 j = 3;
369 break;
370 case 0x3F:
371 j = 2;
372 break;
373 case 0x7F:
374 j = 1;
375 break;
376 default:
377 return -1;
378 }
379 if ((min[i] & mask) != 0 || (max[i] & mask) != mask)
380 return -1;
381 else
382 return i * 8 + j;
383}
384
385/*
386 * Construct a prefix.
387 */
388static int make_addressPrefix(IPAddressOrRange **result,
389 unsigned char *addr, const int prefixlen)
390{
391 int bytelen = (prefixlen + 7) / 8, bitlen = prefixlen % 8;
392 IPAddressOrRange *aor = IPAddressOrRange_new();
393
394 if (aor == NULL)
395 return 0;
396 aor->type = IPAddressOrRange_addressPrefix;
397 if (aor->u.addressPrefix == NULL &&
398 (aor->u.addressPrefix = ASN1_BIT_STRING_new()) == NULL)
399 goto err;
400 if (!ASN1_BIT_STRING_set(aor->u.addressPrefix, addr, bytelen))
401 goto err;
402 aor->u.addressPrefix->flags &= ~7;
403 aor->u.addressPrefix->flags |= ASN1_STRING_FLAG_BITS_LEFT;
404 if (bitlen > 0) {
405 aor->u.addressPrefix->data[bytelen - 1] &= ~(0xFF >> bitlen);
406 aor->u.addressPrefix->flags |= 8 - bitlen;
407 }
408
409 *result = aor;
410 return 1;
411
412 err:
413 IPAddressOrRange_free(aor);
414 return 0;
415}
416
417/*
418 * Construct a range. If it can be expressed as a prefix,
419 * return a prefix instead. Doing this here simplifies
420 * the rest of the code considerably.
421 */
422static int make_addressRange(IPAddressOrRange **result,
423 unsigned char *min,
424 unsigned char *max, const int length)
425{
426 IPAddressOrRange *aor;
427 int i, prefixlen;
428
429 if ((prefixlen = range_should_be_prefix(min, max, length)) >= 0)
430 return make_addressPrefix(result, min, prefixlen);
431
432 if ((aor = IPAddressOrRange_new()) == NULL)
433 return 0;
434 aor->type = IPAddressOrRange_addressRange;
435 if ((aor->u.addressRange = IPAddressRange_new()) == NULL)
436 goto err;
437 if (aor->u.addressRange->min == NULL &&
438 (aor->u.addressRange->min = ASN1_BIT_STRING_new()) == NULL)
439 goto err;
440 if (aor->u.addressRange->max == NULL &&
441 (aor->u.addressRange->max = ASN1_BIT_STRING_new()) == NULL)
442 goto err;
443
444 for (i = length; i > 0 && min[i - 1] == 0x00; --i) ;
445 if (!ASN1_BIT_STRING_set(aor->u.addressRange->min, min, i))
446 goto err;
447 aor->u.addressRange->min->flags &= ~7;
448 aor->u.addressRange->min->flags |= ASN1_STRING_FLAG_BITS_LEFT;
449 if (i > 0) {
450 unsigned char b = min[i - 1];
451 int j = 1;
452 while ((b & (0xFFU >> j)) != 0)
453 ++j;
454 aor->u.addressRange->min->flags |= 8 - j;
455 }
456
457 for (i = length; i > 0 && max[i - 1] == 0xFF; --i) ;
458 if (!ASN1_BIT_STRING_set(aor->u.addressRange->max, max, i))
459 goto err;
460 aor->u.addressRange->max->flags &= ~7;
461 aor->u.addressRange->max->flags |= ASN1_STRING_FLAG_BITS_LEFT;
462 if (i > 0) {
463 unsigned char b = max[i - 1];
464 int j = 1;
465 while ((b & (0xFFU >> j)) != (0xFFU >> j))
466 ++j;
467 aor->u.addressRange->max->flags |= 8 - j;
468 }
469
470 *result = aor;
471 return 1;
472
473 err:
474 IPAddressOrRange_free(aor);
475 return 0;
476}
477
478/*
479 * Construct a new address family or find an existing one.
480 */
481static IPAddressFamily *make_IPAddressFamily(IPAddrBlocks *addr,
482 const unsigned afi,
483 const unsigned *safi)
484{
485 IPAddressFamily *f;
486 unsigned char key[3];
487 int keylen;
488 int i;
489
490 key[0] = (afi >> 8) & 0xFF;
491 key[1] = afi & 0xFF;
492 if (safi != NULL) {
493 key[2] = *safi & 0xFF;
494 keylen = 3;
495 } else {
496 keylen = 2;
497 }
498
499 for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {
500 f = sk_IPAddressFamily_value(addr, i);
501 if (f->addressFamily->length == keylen &&
502 !memcmp(f->addressFamily->data, key, keylen))
503 return f;
504 }
505
506 if ((f = IPAddressFamily_new()) == NULL)
507 goto err;
508 if (f->ipAddressChoice == NULL &&
509 (f->ipAddressChoice = IPAddressChoice_new()) == NULL)
510 goto err;
511 if (f->addressFamily == NULL &&
512 (f->addressFamily = ASN1_OCTET_STRING_new()) == NULL)
513 goto err;
514 if (!ASN1_OCTET_STRING_set(f->addressFamily, key, keylen))
515 goto err;
516 if (!sk_IPAddressFamily_push(addr, f))
517 goto err;
518
519 return f;
520
521 err:
522 IPAddressFamily_free(f);
523 return NULL;
524}
525
526/*
527 * Add an inheritance element.
528 */
529int X509v3_addr_add_inherit(IPAddrBlocks *addr,
530 const unsigned afi, const unsigned *safi)
531{
532 IPAddressFamily *f = make_IPAddressFamily(addr, afi, safi);
533 if (f == NULL ||
534 f->ipAddressChoice == NULL ||
535 (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges &&
536 f->ipAddressChoice->u.addressesOrRanges != NULL))
537 return 0;
538 if (f->ipAddressChoice->type == IPAddressChoice_inherit &&
539 f->ipAddressChoice->u.inherit != NULL)
540 return 1;
541 if (f->ipAddressChoice->u.inherit == NULL &&
542 (f->ipAddressChoice->u.inherit = ASN1_NULL_new()) == NULL)
543 return 0;
544 f->ipAddressChoice->type = IPAddressChoice_inherit;
545 return 1;
546}
547
548/*
549 * Construct an IPAddressOrRange sequence, or return an existing one.
550 */
551static IPAddressOrRanges *make_prefix_or_range(IPAddrBlocks *addr,
552 const unsigned afi,
553 const unsigned *safi)
554{
555 IPAddressFamily *f = make_IPAddressFamily(addr, afi, safi);
556 IPAddressOrRanges *aors = NULL;
557
558 if (f == NULL ||
559 f->ipAddressChoice == NULL ||
560 (f->ipAddressChoice->type == IPAddressChoice_inherit &&
561 f->ipAddressChoice->u.inherit != NULL))
562 return NULL;
563 if (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges)
564 aors = f->ipAddressChoice->u.addressesOrRanges;
565 if (aors != NULL)
566 return aors;
567 if ((aors = sk_IPAddressOrRange_new_null()) == NULL)
568 return NULL;
569 switch (afi) {
570 case IANA_AFI_IPV4:
571 (void)sk_IPAddressOrRange_set_cmp_func(aors, v4IPAddressOrRange_cmp);
572 break;
573 case IANA_AFI_IPV6:
574 (void)sk_IPAddressOrRange_set_cmp_func(aors, v6IPAddressOrRange_cmp);
575 break;
576 }
577 f->ipAddressChoice->type = IPAddressChoice_addressesOrRanges;
578 f->ipAddressChoice->u.addressesOrRanges = aors;
579 return aors;
580}
581
582/*
583 * Add a prefix.
584 */
585int X509v3_addr_add_prefix(IPAddrBlocks *addr,
586 const unsigned afi,
587 const unsigned *safi,
588 unsigned char *a, const int prefixlen)
589{
590 IPAddressOrRanges *aors = make_prefix_or_range(addr, afi, safi);
591 IPAddressOrRange *aor;
592 if (aors == NULL || !make_addressPrefix(&aor, a, prefixlen))
593 return 0;
594 if (sk_IPAddressOrRange_push(aors, aor))
595 return 1;
596 IPAddressOrRange_free(aor);
597 return 0;
598}
599
600/*
601 * Add a range.
602 */
603int X509v3_addr_add_range(IPAddrBlocks *addr,
604 const unsigned afi,
605 const unsigned *safi,
606 unsigned char *min, unsigned char *max)
607{
608 IPAddressOrRanges *aors = make_prefix_or_range(addr, afi, safi);
609 IPAddressOrRange *aor;
610 int length = length_from_afi(afi);
611 if (aors == NULL)
612 return 0;
613 if (!make_addressRange(&aor, min, max, length))
614 return 0;
615 if (sk_IPAddressOrRange_push(aors, aor))
616 return 1;
617 IPAddressOrRange_free(aor);
618 return 0;
619}
620
621/*
622 * Extract min and max values from an IPAddressOrRange.
623 */
624static int extract_min_max(IPAddressOrRange *aor,
625 unsigned char *min, unsigned char *max, int length)
626{
627 if (aor == NULL || min == NULL || max == NULL)
628 return 0;
629 switch (aor->type) {
630 case IPAddressOrRange_addressPrefix:
631 return (addr_expand(min, aor->u.addressPrefix, length, 0x00) &&
632 addr_expand(max, aor->u.addressPrefix, length, 0xFF));
633 case IPAddressOrRange_addressRange:
634 return (addr_expand(min, aor->u.addressRange->min, length, 0x00) &&
635 addr_expand(max, aor->u.addressRange->max, length, 0xFF));
636 }
637 return 0;
638}
639
640/*
641 * Public wrapper for extract_min_max().
642 */
643int X509v3_addr_get_range(IPAddressOrRange *aor,
644 const unsigned afi,
645 unsigned char *min,
646 unsigned char *max, const int length)
647{
648 int afi_length = length_from_afi(afi);
649 if (aor == NULL || min == NULL || max == NULL ||
650 afi_length == 0 || length < afi_length ||
651 (aor->type != IPAddressOrRange_addressPrefix &&
652 aor->type != IPAddressOrRange_addressRange) ||
653 !extract_min_max(aor, min, max, afi_length))
654 return 0;
655
656 return afi_length;
657}
658
659/*
660 * Sort comparison function for a sequence of IPAddressFamily.
661 *
662 * The last paragraph of RFC 3779 2.2.3.3 is slightly ambiguous about
663 * the ordering: I can read it as meaning that IPv6 without a SAFI
664 * comes before IPv4 with a SAFI, which seems pretty weird. The
665 * examples in appendix B suggest that the author intended the
666 * null-SAFI rule to apply only within a single AFI, which is what I
667 * would have expected and is what the following code implements.
668 */
669static int IPAddressFamily_cmp(const IPAddressFamily *const *a_,
670 const IPAddressFamily *const *b_)
671{
672 const ASN1_OCTET_STRING *a = (*a_)->addressFamily;
673 const ASN1_OCTET_STRING *b = (*b_)->addressFamily;
674 int len = ((a->length <= b->length) ? a->length : b->length);
675 int cmp = memcmp(a->data, b->data, len);
676 return cmp ? cmp : a->length - b->length;
677}
678
679/*
680 * Check whether an IPAddrBLocks is in canonical form.
681 */
682int X509v3_addr_is_canonical(IPAddrBlocks *addr)
683{
684 unsigned char a_min[ADDR_RAW_BUF_LEN], a_max[ADDR_RAW_BUF_LEN];
685 unsigned char b_min[ADDR_RAW_BUF_LEN], b_max[ADDR_RAW_BUF_LEN];
686 IPAddressOrRanges *aors;
687 int i, j, k;
688
689 /*
690 * Empty extension is canonical.
691 */
692 if (addr == NULL)
693 return 1;
694
695 /*
696 * Check whether the top-level list is in order.
697 */
698 for (i = 0; i < sk_IPAddressFamily_num(addr) - 1; i++) {
699 const IPAddressFamily *a = sk_IPAddressFamily_value(addr, i);
700 const IPAddressFamily *b = sk_IPAddressFamily_value(addr, i + 1);
701 if (IPAddressFamily_cmp(&a, &b) >= 0)
702 return 0;
703 }
704
705 /*
706 * Top level's ok, now check each address family.
707 */
708 for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {
709 IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);
710 int length = length_from_afi(X509v3_addr_get_afi(f));
711
712 /*
713 * Inheritance is canonical. Anything other than inheritance or
714 * a SEQUENCE OF IPAddressOrRange is an ASN.1 error or something.
715 */
716 if (f == NULL || f->ipAddressChoice == NULL)
717 return 0;
718 switch (f->ipAddressChoice->type) {
719 case IPAddressChoice_inherit:
720 continue;
721 case IPAddressChoice_addressesOrRanges:
722 break;
723 default:
724 return 0;
725 }
726
727 /*
728 * It's an IPAddressOrRanges sequence, check it.
729 */
730 aors = f->ipAddressChoice->u.addressesOrRanges;
731 if (sk_IPAddressOrRange_num(aors) == 0)
732 return 0;
733 for (j = 0; j < sk_IPAddressOrRange_num(aors) - 1; j++) {
734 IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, j);
735 IPAddressOrRange *b = sk_IPAddressOrRange_value(aors, j + 1);
736
737 if (!extract_min_max(a, a_min, a_max, length) ||
738 !extract_min_max(b, b_min, b_max, length))
739 return 0;
740
741 /*
742 * Punt misordered list, overlapping start, or inverted range.
743 */
744 if (memcmp(a_min, b_min, length) >= 0 ||
745 memcmp(a_min, a_max, length) > 0 ||
746 memcmp(b_min, b_max, length) > 0)
747 return 0;
748
749 /*
750 * Punt if adjacent or overlapping. Check for adjacency by
751 * subtracting one from b_min first.
752 */
753 for (k = length - 1; k >= 0 && b_min[k]-- == 0x00; k--) ;
754 if (memcmp(a_max, b_min, length) >= 0)
755 return 0;
756
757 /*
758 * Check for range that should be expressed as a prefix.
759 */
760 if (a->type == IPAddressOrRange_addressRange &&
761 range_should_be_prefix(a_min, a_max, length) >= 0)
762 return 0;
763 }
764
765 /*
766 * Check range to see if it's inverted or should be a
767 * prefix.
768 */
769 j = sk_IPAddressOrRange_num(aors) - 1;
770 {
771 IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, j);
772 if (a != NULL && a->type == IPAddressOrRange_addressRange) {
773 if (!extract_min_max(a, a_min, a_max, length))
774 return 0;
775 if (memcmp(a_min, a_max, length) > 0 ||
776 range_should_be_prefix(a_min, a_max, length) >= 0)
777 return 0;
778 }
779 }
780 }
781
782 /*
783 * If we made it through all that, we're happy.
784 */
785 return 1;
786}
787
788/*
789 * Whack an IPAddressOrRanges into canonical form.
790 */
791static int IPAddressOrRanges_canonize(IPAddressOrRanges *aors,
792 const unsigned afi)
793{
794 int i, j, length = length_from_afi(afi);
795
796 /*
797 * Sort the IPAddressOrRanges sequence.
798 */
799 sk_IPAddressOrRange_sort(aors);
800
801 /*
802 * Clean up representation issues, punt on duplicates or overlaps.
803 */
804 for (i = 0; i < sk_IPAddressOrRange_num(aors) - 1; i++) {
805 IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, i);
806 IPAddressOrRange *b = sk_IPAddressOrRange_value(aors, i + 1);
807 unsigned char a_min[ADDR_RAW_BUF_LEN], a_max[ADDR_RAW_BUF_LEN];
808 unsigned char b_min[ADDR_RAW_BUF_LEN], b_max[ADDR_RAW_BUF_LEN];
809
810 if (!extract_min_max(a, a_min, a_max, length) ||
811 !extract_min_max(b, b_min, b_max, length))
812 return 0;
813
814 /*
815 * Punt inverted ranges.
816 */
817 if (memcmp(a_min, a_max, length) > 0 ||
818 memcmp(b_min, b_max, length) > 0)
819 return 0;
820
821 /*
822 * Punt overlaps.
823 */
824 if (memcmp(a_max, b_min, length) >= 0)
825 return 0;
826
827 /*
828 * Merge if a and b are adjacent. We check for
829 * adjacency by subtracting one from b_min first.
830 */
831 for (j = length - 1; j >= 0 && b_min[j]-- == 0x00; j--) ;
832 if (memcmp(a_max, b_min, length) == 0) {
833 IPAddressOrRange *merged;
834 if (!make_addressRange(&merged, a_min, b_max, length))
835 return 0;
836 (void)sk_IPAddressOrRange_set(aors, i, merged);
837 (void)sk_IPAddressOrRange_delete(aors, i + 1);
838 IPAddressOrRange_free(a);
839 IPAddressOrRange_free(b);
840 --i;
841 continue;
842 }
843 }
844
845 /*
846 * Check for inverted final range.
847 */
848 j = sk_IPAddressOrRange_num(aors) - 1;
849 {
850 IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, j);
851 if (a != NULL && a->type == IPAddressOrRange_addressRange) {
852 unsigned char a_min[ADDR_RAW_BUF_LEN], a_max[ADDR_RAW_BUF_LEN];
853 if (!extract_min_max(a, a_min, a_max, length))
854 return 0;
855 if (memcmp(a_min, a_max, length) > 0)
856 return 0;
857 }
858 }
859
860 return 1;
861}
862
863/*
864 * Whack an IPAddrBlocks extension into canonical form.
865 */
866int X509v3_addr_canonize(IPAddrBlocks *addr)
867{
868 int i;
869 for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {
870 IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);
871 if (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges &&
872 !IPAddressOrRanges_canonize(f->ipAddressChoice->
873 u.addressesOrRanges,
874 X509v3_addr_get_afi(f)))
875 return 0;
876 }
877 (void)sk_IPAddressFamily_set_cmp_func(addr, IPAddressFamily_cmp);
878 sk_IPAddressFamily_sort(addr);
879 if (!ossl_assert(X509v3_addr_is_canonical(addr)))
880 return 0;
881 return 1;
882}
883
884/*
885 * v2i handler for the IPAddrBlocks extension.
886 */
887static void *v2i_IPAddrBlocks(const struct v3_ext_method *method,
888 struct v3_ext_ctx *ctx,
889 STACK_OF(CONF_VALUE) *values)
890{
891 static const char v4addr_chars[] = "0123456789.";
892 static const char v6addr_chars[] = "0123456789.:abcdefABCDEF";
893 IPAddrBlocks *addr = NULL;
894 char *s = NULL, *t;
895 int i;
896
897 if ((addr = sk_IPAddressFamily_new(IPAddressFamily_cmp)) == NULL) {
898 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);
899 return NULL;
900 }
901
902 for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
903 CONF_VALUE *val = sk_CONF_VALUE_value(values, i);
904 unsigned char min[ADDR_RAW_BUF_LEN], max[ADDR_RAW_BUF_LEN];
905 unsigned afi, *safi = NULL, safi_;
906 const char *addr_chars = NULL;
907 int prefixlen, i1, i2, delim, length;
908
909 if (!v3_name_cmp(val->name, "IPv4")) {
910 afi = IANA_AFI_IPV4;
911 } else if (!v3_name_cmp(val->name, "IPv6")) {
912 afi = IANA_AFI_IPV6;
913 } else if (!v3_name_cmp(val->name, "IPv4-SAFI")) {
914 afi = IANA_AFI_IPV4;
915 safi = &safi_;
916 } else if (!v3_name_cmp(val->name, "IPv6-SAFI")) {
917 afi = IANA_AFI_IPV6;
918 safi = &safi_;
919 } else {
920 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
921 X509V3_R_EXTENSION_NAME_ERROR);
922 X509V3_conf_err(val);
923 goto err;
924 }
925
926 switch (afi) {
927 case IANA_AFI_IPV4:
928 addr_chars = v4addr_chars;
929 break;
930 case IANA_AFI_IPV6:
931 addr_chars = v6addr_chars;
932 break;
933 }
934
935 length = length_from_afi(afi);
936
937 /*
938 * Handle SAFI, if any, and OPENSSL_strdup() so we can null-terminate
939 * the other input values.
940 */
941 if (safi != NULL) {
942 *safi = strtoul(val->value, &t, 0);
943 t += strspn(t, " \t");
944 if (*safi > 0xFF || *t++ != ':') {
945 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_SAFI);
946 X509V3_conf_err(val);
947 goto err;
948 }
949 t += strspn(t, " \t");
950 s = OPENSSL_strdup(t);
951 } else {
952 s = OPENSSL_strdup(val->value);
953 }
954 if (s == NULL) {
955 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);
956 goto err;
957 }
958
959 /*
960 * Check for inheritance. Not worth additional complexity to
961 * optimize this (seldom-used) case.
962 */
963 if (strcmp(s, "inherit") == 0) {
964 if (!X509v3_addr_add_inherit(addr, afi, safi)) {
965 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
966 X509V3_R_INVALID_INHERITANCE);
967 X509V3_conf_err(val);
968 goto err;
969 }
970 OPENSSL_free(s);
971 s = NULL;
972 continue;
973 }
974
975 i1 = strspn(s, addr_chars);
976 i2 = i1 + strspn(s + i1, " \t");
977 delim = s[i2++];
978 s[i1] = '\0';
979
980 if (a2i_ipadd(min, s) != length) {
981 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_IPADDRESS);
982 X509V3_conf_err(val);
983 goto err;
984 }
985
986 switch (delim) {
987 case '/':
988 prefixlen = (int)strtoul(s + i2, &t, 10);
989 if (t == s + i2 || *t != '\0') {
990 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
991 X509V3_R_EXTENSION_VALUE_ERROR);
992 X509V3_conf_err(val);
993 goto err;
994 }
995 if (!X509v3_addr_add_prefix(addr, afi, safi, min, prefixlen)) {
996 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);
997 goto err;
998 }
999 break;
1000 case '-':
1001 i1 = i2 + strspn(s + i2, " \t");
1002 i2 = i1 + strspn(s + i1, addr_chars);
1003 if (i1 == i2 || s[i2] != '\0') {
1004 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
1005 X509V3_R_EXTENSION_VALUE_ERROR);
1006 X509V3_conf_err(val);
1007 goto err;
1008 }
1009 if (a2i_ipadd(max, s + i1) != length) {
1010 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
1011 X509V3_R_INVALID_IPADDRESS);
1012 X509V3_conf_err(val);
1013 goto err;
1014 }
1015 if (memcmp(min, max, length_from_afi(afi)) > 0) {
1016 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
1017 X509V3_R_EXTENSION_VALUE_ERROR);
1018 X509V3_conf_err(val);
1019 goto err;
1020 }
1021 if (!X509v3_addr_add_range(addr, afi, safi, min, max)) {
1022 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);
1023 goto err;
1024 }
1025 break;
1026 case '\0':
1027 if (!X509v3_addr_add_prefix(addr, afi, safi, min, length * 8)) {
1028 X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);
1029 goto err;
1030 }
1031 break;
1032 default:
1033 X509V3err(X509V3_F_V2I_IPADDRBLOCKS,
1034 X509V3_R_EXTENSION_VALUE_ERROR);
1035 X509V3_conf_err(val);
1036 goto err;
1037 }
1038
1039 OPENSSL_free(s);
1040 s = NULL;
1041 }
1042
1043 /*
1044 * Canonize the result, then we're done.
1045 */
1046 if (!X509v3_addr_canonize(addr))
1047 goto err;
1048 return addr;
1049
1050 err:
1051 OPENSSL_free(s);
1052 sk_IPAddressFamily_pop_free(addr, IPAddressFamily_free);
1053 return NULL;
1054}
1055
1056/*
1057 * OpenSSL dispatch
1058 */
1059const X509V3_EXT_METHOD v3_addr = {
1060 NID_sbgp_ipAddrBlock, /* nid */
1061 0, /* flags */
1062 ASN1_ITEM_ref(IPAddrBlocks), /* template */
1063 0, 0, 0, 0, /* old functions, ignored */
1064 0, /* i2s */
1065 0, /* s2i */
1066 0, /* i2v */
1067 v2i_IPAddrBlocks, /* v2i */
1068 i2r_IPAddrBlocks, /* i2r */
1069 0, /* r2i */
1070 NULL /* extension-specific data */
1071};
1072
1073/*
1074 * Figure out whether extension sues inheritance.
1075 */
1076int X509v3_addr_inherits(IPAddrBlocks *addr)
1077{
1078 int i;
1079 if (addr == NULL)
1080 return 0;
1081 for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {
1082 IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);
1083 if (f->ipAddressChoice->type == IPAddressChoice_inherit)
1084 return 1;
1085 }
1086 return 0;
1087}
1088
1089/*
1090 * Figure out whether parent contains child.
1091 */
1092static int addr_contains(IPAddressOrRanges *parent,
1093 IPAddressOrRanges *child, int length)
1094{
1095 unsigned char p_min[ADDR_RAW_BUF_LEN], p_max[ADDR_RAW_BUF_LEN];
1096 unsigned char c_min[ADDR_RAW_BUF_LEN], c_max[ADDR_RAW_BUF_LEN];
1097 int p, c;
1098
1099 if (child == NULL || parent == child)
1100 return 1;
1101 if (parent == NULL)
1102 return 0;
1103
1104 p = 0;
1105 for (c = 0; c < sk_IPAddressOrRange_num(child); c++) {
1106 if (!extract_min_max(sk_IPAddressOrRange_value(child, c),
1107 c_min, c_max, length))
1108 return -1;
1109 for (;; p++) {
1110 if (p >= sk_IPAddressOrRange_num(parent))
1111 return 0;
1112 if (!extract_min_max(sk_IPAddressOrRange_value(parent, p),
1113 p_min, p_max, length))
1114 return 0;
1115 if (memcmp(p_max, c_max, length) < 0)
1116 continue;
1117 if (memcmp(p_min, c_min, length) > 0)
1118 return 0;
1119 break;
1120 }
1121 }
1122
1123 return 1;
1124}
1125
1126/*
1127 * Test whether a is a subset of b.
1128 */
1129int X509v3_addr_subset(IPAddrBlocks *a, IPAddrBlocks *b)
1130{
1131 int i;
1132 if (a == NULL || a == b)
1133 return 1;
1134 if (b == NULL || X509v3_addr_inherits(a) || X509v3_addr_inherits(b))
1135 return 0;
1136 (void)sk_IPAddressFamily_set_cmp_func(b, IPAddressFamily_cmp);
1137 for (i = 0; i < sk_IPAddressFamily_num(a); i++) {
1138 IPAddressFamily *fa = sk_IPAddressFamily_value(a, i);
1139 int j = sk_IPAddressFamily_find(b, fa);
1140 IPAddressFamily *fb;
1141 fb = sk_IPAddressFamily_value(b, j);
1142 if (fb == NULL)
1143 return 0;
1144 if (!addr_contains(fb->ipAddressChoice->u.addressesOrRanges,
1145 fa->ipAddressChoice->u.addressesOrRanges,
1146 length_from_afi(X509v3_addr_get_afi(fb))))
1147 return 0;
1148 }
1149 return 1;
1150}
1151
1152/*
1153 * Validation error handling via callback.
1154 */
1155#define validation_err(_err_) \
1156 do { \
1157 if (ctx != NULL) { \
1158 ctx->error = _err_; \
1159 ctx->error_depth = i; \
1160 ctx->current_cert = x; \
1161 ret = ctx->verify_cb(0, ctx); \
1162 } else { \
1163 ret = 0; \
1164 } \
1165 if (!ret) \
1166 goto done; \
1167 } while (0)
1168
1169/*
1170 * Core code for RFC 3779 2.3 path validation.
1171 *
1172 * Returns 1 for success, 0 on error.
1173 *
1174 * When returning 0, ctx->error MUST be set to an appropriate value other than
1175 * X509_V_OK.
1176 */
1177static int addr_validate_path_internal(X509_STORE_CTX *ctx,
1178 STACK_OF(X509) *chain,
1179 IPAddrBlocks *ext)
1180{
1181 IPAddrBlocks *child = NULL;
1182 int i, j, ret = 1;
1183 X509 *x;
1184
1185 if (!ossl_assert(chain != NULL && sk_X509_num(chain) > 0)
1186 || !ossl_assert(ctx != NULL || ext != NULL)
1187 || !ossl_assert(ctx == NULL || ctx->verify_cb != NULL)) {
1188 if (ctx != NULL)
1189 ctx->error = X509_V_ERR_UNSPECIFIED;
1190 return 0;
1191 }
1192
1193 /*
1194 * Figure out where to start. If we don't have an extension to
1195 * check, we're done. Otherwise, check canonical form and
1196 * set up for walking up the chain.
1197 */
1198 if (ext != NULL) {
1199 i = -1;
1200 x = NULL;
1201 } else {
1202 i = 0;
1203 x = sk_X509_value(chain, i);
1204 if ((ext = x->rfc3779_addr) == NULL)
1205 goto done;
1206 }
1207 if (!X509v3_addr_is_canonical(ext))
1208 validation_err(X509_V_ERR_INVALID_EXTENSION);
1209 (void)sk_IPAddressFamily_set_cmp_func(ext, IPAddressFamily_cmp);
1210 if ((child = sk_IPAddressFamily_dup(ext)) == NULL) {
1211 X509V3err(X509V3_F_ADDR_VALIDATE_PATH_INTERNAL,
1212 ERR_R_MALLOC_FAILURE);
1213 if (ctx != NULL)
1214 ctx->error = X509_V_ERR_OUT_OF_MEM;
1215 ret = 0;
1216 goto done;
1217 }
1218
1219 /*
1220 * Now walk up the chain. No cert may list resources that its
1221 * parent doesn't list.
1222 */
1223 for (i++; i < sk_X509_num(chain); i++) {
1224 x = sk_X509_value(chain, i);
1225 if (!X509v3_addr_is_canonical(x->rfc3779_addr))
1226 validation_err(X509_V_ERR_INVALID_EXTENSION);
1227 if (x->rfc3779_addr == NULL) {
1228 for (j = 0; j < sk_IPAddressFamily_num(child); j++) {
1229 IPAddressFamily *fc = sk_IPAddressFamily_value(child, j);
1230 if (fc->ipAddressChoice->type != IPAddressChoice_inherit) {
1231 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
1232 break;
1233 }
1234 }
1235 continue;
1236 }
1237 (void)sk_IPAddressFamily_set_cmp_func(x->rfc3779_addr,
1238 IPAddressFamily_cmp);
1239 for (j = 0; j < sk_IPAddressFamily_num(child); j++) {
1240 IPAddressFamily *fc = sk_IPAddressFamily_value(child, j);
1241 int k = sk_IPAddressFamily_find(x->rfc3779_addr, fc);
1242 IPAddressFamily *fp =
1243 sk_IPAddressFamily_value(x->rfc3779_addr, k);
1244 if (fp == NULL) {
1245 if (fc->ipAddressChoice->type ==
1246 IPAddressChoice_addressesOrRanges) {
1247 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
1248 break;
1249 }
1250 continue;
1251 }
1252 if (fp->ipAddressChoice->type ==
1253 IPAddressChoice_addressesOrRanges) {
1254 if (fc->ipAddressChoice->type == IPAddressChoice_inherit
1255 || addr_contains(fp->ipAddressChoice->u.addressesOrRanges,
1256 fc->ipAddressChoice->u.addressesOrRanges,
1257 length_from_afi(X509v3_addr_get_afi(fc))))
1258 sk_IPAddressFamily_set(child, j, fp);
1259 else
1260 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
1261 }
1262 }
1263 }
1264
1265 /*
1266 * Trust anchor can't inherit.
1267 */
1268 if (x->rfc3779_addr != NULL) {
1269 for (j = 0; j < sk_IPAddressFamily_num(x->rfc3779_addr); j++) {
1270 IPAddressFamily *fp =
1271 sk_IPAddressFamily_value(x->rfc3779_addr, j);
1272 if (fp->ipAddressChoice->type == IPAddressChoice_inherit
1273 && sk_IPAddressFamily_find(child, fp) >= 0)
1274 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
1275 }
1276 }
1277
1278 done:
1279 sk_IPAddressFamily_free(child);
1280 return ret;
1281}
1282
1283#undef validation_err
1284
1285/*
1286 * RFC 3779 2.3 path validation -- called from X509_verify_cert().
1287 */
1288int X509v3_addr_validate_path(X509_STORE_CTX *ctx)
1289{
1290 if (ctx->chain == NULL
1291 || sk_X509_num(ctx->chain) == 0
1292 || ctx->verify_cb == NULL) {
1293 ctx->error = X509_V_ERR_UNSPECIFIED;
1294 return 0;
1295 }
1296 return addr_validate_path_internal(ctx, ctx->chain, NULL);
1297}
1298
1299/*
1300 * RFC 3779 2.3 path validation of an extension.
1301 * Test whether chain covers extension.
1302 */
1303int X509v3_addr_validate_resource_set(STACK_OF(X509) *chain,
1304 IPAddrBlocks *ext, int allow_inheritance)
1305{
1306 if (ext == NULL)
1307 return 1;
1308 if (chain == NULL || sk_X509_num(chain) == 0)
1309 return 0;
1310 if (!allow_inheritance && X509v3_addr_inherits(ext))
1311 return 0;
1312 return addr_validate_path_internal(NULL, chain, ext);
1313}
1314
1315#endif /* OPENSSL_NO_RFC3779 */
1316