/*

  * Contributed to the OpenSSL Project by the American Registry for

  * Internet Numbers ("ARIN").

  */

 /* ====================================================================

  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  * 1. Redistributions of source code must retain the above copyright

  *    notice, this list of conditions and the following disclaimer. 

  *

  * 2. Redistributions in binary form must reproduce the above copyright

  *    notice, this list of conditions and the following disclaimer in

  *    the documentation and/or other materials provided with the

  *    distribution.

  *

  * 3. All advertising materials mentioning features or use of this

  *    software must display the following acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

  *

  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

  *    endorse or promote products derived from this software without

  *    prior written permission. For written permission, please contact

  *    licensing@OpenSSL.org.

  *

  * 5. Products derived from this software may not be called "OpenSSL"

  *    nor may "OpenSSL" appear in their names without prior written

  *    permission of the OpenSSL Project.

  *

  * 6. Redistributions of any form whatsoever must retain the following

  *    acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

  *

  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

  * OF THE POSSIBILITY OF SUCH DAMAGE.

  * ====================================================================

  *

  * This product includes cryptographic software written by Eric Young

  * (eay@cryptsoft.com).  This product includes software written by Tim

  * Hudson (tjh@cryptsoft.com).

  */

 /*

  * Implementation of RFC 3779 section 2.2.

  */

 #include <stdio.h>

 #include <stdlib.h>

 #include <assert.h>

 #include "cryptlib.h"

 #include <openssl/conf.h>

 #include <openssl/asn1.h>

 #include <openssl/asn1t.h>

 #include <openssl/buffer.h>

 #include <openssl/x509v3.h>

 #ifndef OPENSSL_NO_RFC3779

 /*

  * OpenSSL ASN.1 template translation of RFC 3779 2.2.3.

  */

 ASN1_SEQUENCE(IPAddressRange) = {

   ASN1_SIMPLE(IPAddressRange, min, ASN1_BIT_STRING),

   ASN1_SIMPLE(IPAddressRange, max, ASN1_BIT_STRING)

 } ASN1_SEQUENCE_END(IPAddressRange)

 ASN1_CHOICE(IPAddressOrRange) = {

   ASN1_SIMPLE(IPAddressOrRange, u.addressPrefix, ASN1_BIT_STRING),

   ASN1_SIMPLE(IPAddressOrRange, u.addressRange,  IPAddressRange)

 } ASN1_CHOICE_END(IPAddressOrRange)

 ASN1_CHOICE(IPAddressChoice) = {

   ASN1_SIMPLE(IPAddressChoice,      u.inherit,           ASN1_NULL),

   ASN1_SEQUENCE_OF(IPAddressChoice, u.addressesOrRanges, IPAddressOrRange)

 } ASN1_CHOICE_END(IPAddressChoice)

 ASN1_SEQUENCE(IPAddressFamily) = {

   ASN1_SIMPLE(IPAddressFamily, addressFamily,   ASN1_OCTET_STRING),

   ASN1_SIMPLE(IPAddressFamily, ipAddressChoice, IPAddressChoice)

 } ASN1_SEQUENCE_END(IPAddressFamily)

 ASN1_ITEM_TEMPLATE(IPAddrBlocks) = 

   ASN1_EX_TEMPLATE_TYPE(ASN1_TFLG_SEQUENCE_OF, 0,

 			IPAddrBlocks, IPAddressFamily)

 ASN1_ITEM_TEMPLATE_END(IPAddrBlocks)

 IMPLEMENT_ASN1_FUNCTIONS(IPAddressRange)

 IMPLEMENT_ASN1_FUNCTIONS(IPAddressOrRange)

 IMPLEMENT_ASN1_FUNCTIONS(IPAddressChoice)

 IMPLEMENT_ASN1_FUNCTIONS(IPAddressFamily)

 /*

  * How much buffer space do we need for a raw address?

  */

 #define ADDR_RAW_BUF_LEN	16

 /*

  * What's the address length associated with this AFI?

  */

 static int length_from_afi(const unsigned afi)

 {

   switch (afi) {

   case IANA_AFI_IPV4:

     return 4;

   case IANA_AFI_IPV6:

     return 16;

   default:

     return 0;

   }

 }

 /*

  * Extract the AFI from an IPAddressFamily.

  */

 unsigned v3_addr_get_afi(const IPAddressFamily *f)

 {

   return ((f != NULL &&

 	   f->addressFamily != NULL &&

 	   f->addressFamily->data != NULL)

 	  ? ((f->addressFamily->data[0] << 8) |

 	     (f->addressFamily->data[1]))

 	  : 0);

 }

 /*

  * Expand the bitstring form of an address into a raw byte array.

  * At the moment this is coded for simplicity, not speed.

  */

 static void addr_expand(unsigned char *addr,

 			const ASN1_BIT_STRING *bs,

 			const int length,

 			const unsigned char fill)

 {

   assert(bs->length >= 0 && bs->length <= length);

   if (bs->length > 0) {

     memcpy(addr, bs->data, bs->length);

     if ((bs->flags & 7) != 0) {

       unsigned char mask = 0xFF >> (8 - (bs->flags & 7));

       if (fill == 0)

 	addr[bs->length - 1] &= ~mask;

       else

 	addr[bs->length - 1] |= mask;

     }

   }

   memset(addr + bs->length, fill, length - bs->length);

 }

 /*

  * Extract the prefix length from a bitstring.

  */

 #define addr_prefixlen(bs) ((int) ((bs)->length * 8 - ((bs)->flags & 7)))

 /*

  * i2r handler for one address bitstring.

  */

 static int i2r_address(BIO *out,

 		       const unsigned afi,

 		       const unsigned char fill,

 		       const ASN1_BIT_STRING *bs)

 {

   unsigned char addr[ADDR_RAW_BUF_LEN];

   int i, n;

   switch (afi) {

   case IANA_AFI_IPV4:

     addr_expand(addr, bs, 4, fill);

     BIO_printf(out, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);

     break;

   case IANA_AFI_IPV6:

     addr_expand(addr, bs, 16, fill);

     for (n = 16; n > 1 && addr[n-1] == 0x00 && addr[n-2] == 0x00; n -= 2)

       ;

     for (i = 0; i < n; i += 2)

       BIO_printf(out, "%x%s", (addr[i] << 8) | addr[i+1], (i < 14 ? ":" : ""));

     if (i < 16)

       BIO_puts(out, ":");

     break;

   default:

     for (i = 0; i < bs->length; i++)

       BIO_printf(out, "%s%02x", (i > 0 ? ":" : ""), bs->data[i]);

     BIO_printf(out, "[%d]", (int) (bs->flags & 7));

     break;

   }

   return 1;

 }

 /*

  * i2r handler for a sequence of addresses and ranges.

  */

 static int i2r_IPAddressOrRanges(BIO *out,

 				 const int indent,

 				 const IPAddressOrRanges *aors,

 				 const unsigned afi)

 {

   int i;

   for (i = 0; i < sk_IPAddressOrRange_num(aors); i++) {

     const IPAddressOrRange *aor = sk_IPAddressOrRange_value(aors, i);

     BIO_printf(out, "%*s", indent, "");

     switch (aor->type) {

     case IPAddressOrRange_addressPrefix:

       if (!i2r_address(out, afi, 0x00, aor->u.addressPrefix))

 	return 0;

       BIO_printf(out, "/%d\n", addr_prefixlen(aor->u.addressPrefix));

       continue;

     case IPAddressOrRange_addressRange:

       if (!i2r_address(out, afi, 0x00, aor->u.addressRange->min))

 	return 0;

       BIO_puts(out, "-");

       if (!i2r_address(out, afi, 0xFF, aor->u.addressRange->max))

 	return 0;

       BIO_puts(out, "\n");

       continue;

     }

   }

   return 1;

 }

 /*

  * i2r handler for an IPAddrBlocks extension.

  */

 static int i2r_IPAddrBlocks(X509V3_EXT_METHOD *method,

 			    void *ext,

 			    BIO *out,

 			    int indent)

 {

   const IPAddrBlocks *addr = ext;

   int i;

   for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {

     IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);

     const unsigned afi = v3_addr_get_afi(f);

     switch (afi) {

     case IANA_AFI_IPV4:

       BIO_printf(out, "%*sIPv4", indent, "");

       break;

     case IANA_AFI_IPV6:

       BIO_printf(out, "%*sIPv6", indent, "");

       break;

     default:

       BIO_printf(out, "%*sUnknown AFI %u", indent, "", afi);

       break;

     }

     if (f->addressFamily->length > 2) {

       switch (f->addressFamily->data[2]) {

       case   1:

 	BIO_puts(out, " (Unicast)");

 	break;

       case   2:

 	BIO_puts(out, " (Multicast)");

 	break;

       case   3:

 	BIO_puts(out, " (Unicast/Multicast)");

 	break;

       case   4:

 	BIO_puts(out, " (MPLS)");

 	break;

       case  64:

 	BIO_puts(out, " (Tunnel)");

 	break;

       case  65:

 	BIO_puts(out, " (VPLS)");

 	break;

       case  66:

 	BIO_puts(out, " (BGP MDT)");

 	break;

       case 128:

 	BIO_puts(out, " (MPLS-labeled VPN)");

 	break;

       default:  

 	BIO_printf(out, " (Unknown SAFI %u)",

 		   (unsigned) f->addressFamily->data[2]);

 	break;

       }

     }

     switch (f->ipAddressChoice->type) {

     case IPAddressChoice_inherit:

       BIO_puts(out, ": inherit\n");

       break;

     case IPAddressChoice_addressesOrRanges:

       BIO_puts(out, ":\n");

       if (!i2r_IPAddressOrRanges(out,

 				 indent + 2,

 				 f->ipAddressChoice->u.addressesOrRanges,

 				 afi))

 	return 0;

       break;

     }

   }

   return 1;

 }

 /*

  * Sort comparison function for a sequence of IPAddressOrRange

  * elements.

  */

 static int IPAddressOrRange_cmp(const IPAddressOrRange *a,

 				const IPAddressOrRange *b,

 				const int length)

 {

   unsigned char addr_a[ADDR_RAW_BUF_LEN], addr_b[ADDR_RAW_BUF_LEN];

   int prefixlen_a = 0;

   int prefixlen_b = 0;

   int r;

   switch (a->type) {

   case IPAddressOrRange_addressPrefix:

     addr_expand(addr_a, a->u.addressPrefix, length, 0x00);

     prefixlen_a = addr_prefixlen(a->u.addressPrefix);

     break;

   case IPAddressOrRange_addressRange:

     addr_expand(addr_a, a->u.addressRange->min, length, 0x00);

     prefixlen_a = length * 8;

     break;

   }

   switch (b->type) {

   case IPAddressOrRange_addressPrefix:

     addr_expand(addr_b, b->u.addressPrefix, length, 0x00);

     prefixlen_b = addr_prefixlen(b->u.addressPrefix);

     break;

   case IPAddressOrRange_addressRange:

     addr_expand(addr_b, b->u.addressRange->min, length, 0x00);

     prefixlen_b = length * 8;

     break;

   }

   if ((r = memcmp(addr_a, addr_b, length)) != 0)

     return r;

   else

     return prefixlen_a - prefixlen_b;

 }

 /*

  * IPv4-specific closure over IPAddressOrRange_cmp, since sk_sort()

  * comparision routines are only allowed two arguments.

  */

 static int v4IPAddressOrRange_cmp(const IPAddressOrRange * const *a,

 				  const IPAddressOrRange * const *b)

 {

   return IPAddressOrRange_cmp(*a, *b, 4);

 }

 /*

  * IPv6-specific closure over IPAddressOrRange_cmp, since sk_sort()

  * comparision routines are only allowed two arguments.

  */

 static int v6IPAddressOrRange_cmp(const IPAddressOrRange * const *a,

 				  const IPAddressOrRange * const *b)

 {

   return IPAddressOrRange_cmp(*a, *b, 16);

 }

 /*

  * Calculate whether a range collapses to a prefix.

  * See last paragraph of RFC 3779 2.2.3.7.

  */

 static int range_should_be_prefix(const unsigned char *min,

 				  const unsigned char *max,

 				  const int length)

 {

   unsigned char mask;

   int i, j;

   for (i = 0; i < length && min[i] == max[i]; i++)

     ;

   for (j = length - 1; j >= 0 && min[j] == 0x00 && max[j] == 0xFF; j--)

     ;

   if (i < j)

     return -1;

   if (i > j)

     return i * 8;

   mask = min[i] ^ max[i];

   switch (mask) {

   case 0x01: j = 7; break;

   case 0x03: j = 6; break;

   case 0x07: j = 5; break;

   case 0x0F: j = 4; break;

   case 0x1F: j = 3; break;

   case 0x3F: j = 2; break;

   case 0x7F: j = 1; break;

   default:   return -1;

   }

   if ((min[i] & mask) != 0 || (max[i] & mask) != mask)

     return -1;

   else

     return i * 8 + j;

 }

 /*

  * Construct a prefix.

  */

 static int make_addressPrefix(IPAddressOrRange **result,

 			      unsigned char *addr,

 			      const int prefixlen)

 {

   int bytelen = (prefixlen + 7) / 8, bitlen = prefixlen % 8;

   IPAddressOrRange *aor = IPAddressOrRange_new();

   if (aor == NULL)

     return 0;

   aor->type = IPAddressOrRange_addressPrefix;

   if (aor->u.addressPrefix == NULL &&

       (aor->u.addressPrefix = ASN1_BIT_STRING_new()) == NULL)

     goto err;

   if (!ASN1_BIT_STRING_set(aor->u.addressPrefix, addr, bytelen))

     goto err;

   aor->u.addressPrefix->flags &= ~7;

   aor->u.addressPrefix->flags |= ASN1_STRING_FLAG_BITS_LEFT;

   if (bitlen > 0) {

     aor->u.addressPrefix->data[bytelen - 1] &= ~(0xFF >> bitlen);

     aor->u.addressPrefix->flags |= 8 - bitlen;

   }

   *result = aor;

   return 1;

  err:

   IPAddressOrRange_free(aor);

   return 0;

 }

 /*

  * Construct a range.  If it can be expressed as a prefix,

  * return a prefix instead.  Doing this here simplifies

  * the rest of the code considerably.

  */

 static int make_addressRange(IPAddressOrRange **result,

 			     unsigned char *min,

 			     unsigned char *max,

 			     const int length)

 {

   IPAddressOrRange *aor;

   int i, prefixlen;

   if ((prefixlen = range_should_be_prefix(min, max, length)) >= 0)

     return make_addressPrefix(result, min, prefixlen);

   if ((aor = IPAddressOrRange_new()) == NULL)

     return 0;

   aor->type = IPAddressOrRange_addressRange;

   assert(aor->u.addressRange == NULL);

   if ((aor->u.addressRange = IPAddressRange_new()) == NULL)

     goto err;

   if (aor->u.addressRange->min == NULL &&

       (aor->u.addressRange->min = ASN1_BIT_STRING_new()) == NULL)

     goto err;

   if (aor->u.addressRange->max == NULL &&

       (aor->u.addressRange->max = ASN1_BIT_STRING_new()) == NULL)

     goto err;

   for (i = length; i > 0 && min[i - 1] == 0x00; --i)

     ;

   if (!ASN1_BIT_STRING_set(aor->u.addressRange->min, min, i))

     goto err;

   aor->u.addressRange->min->flags &= ~7;

   aor->u.addressRange->min->flags |= ASN1_STRING_FLAG_BITS_LEFT;

   if (i > 0) {

     unsigned char b = min[i - 1];

     int j = 1;

     while ((b & (0xFFU >> j)) != 0) 

       ++j;

     aor->u.addressRange->min->flags |= 8 - j;

   }

   for (i = length; i > 0 && max[i - 1] == 0xFF; --i)

     ;

   if (!ASN1_BIT_STRING_set(aor->u.addressRange->max, max, i))

     goto err;

   aor->u.addressRange->max->flags &= ~7;

   aor->u.addressRange->max->flags |= ASN1_STRING_FLAG_BITS_LEFT;

   if (i > 0) {

     unsigned char b = max[i - 1];

     int j = 1;

     while ((b & (0xFFU >> j)) != (0xFFU >> j))

       ++j;

     aor->u.addressRange->max->flags |= 8 - j;

   }

   *result = aor;

   return 1;

  err:

   IPAddressOrRange_free(aor);

   return 0;

 }

 /*

  * Construct a new address family or find an existing one.

  */

 static IPAddressFamily *make_IPAddressFamily(IPAddrBlocks *addr,

 					     const unsigned afi,

 					     const unsigned *safi)

 {

   IPAddressFamily *f;

   unsigned char key[3];

   unsigned keylen;

   int i;

   key[0] = (afi >> 8) & 0xFF;

   key[1] = afi & 0xFF;

   if (safi != NULL) {

     key[2] = *safi & 0xFF;

     keylen = 3;

   } else {

     keylen = 2;

   }

   for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {

     f = sk_IPAddressFamily_value(addr, i);

     assert(f->addressFamily->data != NULL);

     if (f->addressFamily->length == keylen &&

 	!memcmp(f->addressFamily->data, key, keylen))

       return f;

   }

   if ((f = IPAddressFamily_new()) == NULL)

     goto err;

   if (f->ipAddressChoice == NULL &&

       (f->ipAddressChoice = IPAddressChoice_new()) == NULL)

     goto err;

   if (f->addressFamily == NULL && 

       (f->addressFamily = ASN1_OCTET_STRING_new()) == NULL)

     goto err;

   if (!ASN1_OCTET_STRING_set(f->addressFamily, key, keylen))

     goto err;

   if (!sk_IPAddressFamily_push(addr, f))

     goto err;

   return f;

  err:

   IPAddressFamily_free(f);

   return NULL;

 }

 /*

  * Add an inheritance element.

  */

 int v3_addr_add_inherit(IPAddrBlocks *addr,

 			const unsigned afi,

 			const unsigned *safi)

 {

   IPAddressFamily *f = make_IPAddressFamily(addr, afi, safi);

   if (f == NULL ||

       f->ipAddressChoice == NULL ||

       (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges &&

        f->ipAddressChoice->u.addressesOrRanges != NULL))

     return 0;

   if (f->ipAddressChoice->type == IPAddressChoice_inherit &&

       f->ipAddressChoice->u.inherit != NULL)

     return 1;

   if (f->ipAddressChoice->u.inherit == NULL &&

       (f->ipAddressChoice->u.inherit = ASN1_NULL_new()) == NULL)

     return 0;

   f->ipAddressChoice->type = IPAddressChoice_inherit;

   return 1;

 }

 /*

  * Construct an IPAddressOrRange sequence, or return an existing one.

  */

 static IPAddressOrRanges *make_prefix_or_range(IPAddrBlocks *addr,

 					       const unsigned afi,

 					       const unsigned *safi)

 {

   IPAddressFamily *f = make_IPAddressFamily(addr, afi, safi);

   IPAddressOrRanges *aors = NULL;

   if (f == NULL ||

       f->ipAddressChoice == NULL ||

       (f->ipAddressChoice->type == IPAddressChoice_inherit &&

        f->ipAddressChoice->u.inherit != NULL))

     return NULL;

   if (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges)

     aors = f->ipAddressChoice->u.addressesOrRanges;

   if (aors != NULL)

     return aors;

   if ((aors = sk_IPAddressOrRange_new_null()) == NULL)

     return NULL;

   switch (afi) {

   case IANA_AFI_IPV4:

     sk_IPAddressOrRange_set_cmp_func(aors, v4IPAddressOrRange_cmp);

     break;

   case IANA_AFI_IPV6:

     sk_IPAddressOrRange_set_cmp_func(aors, v6IPAddressOrRange_cmp);

     break;

   }

   f->ipAddressChoice->type = IPAddressChoice_addressesOrRanges;

   f->ipAddressChoice->u.addressesOrRanges = aors;

   return aors;

 }

 /*

  * Add a prefix.

  */

 int v3_addr_add_prefix(IPAddrBlocks *addr,

 		       const unsigned afi,

 		       const unsigned *safi,

 		       unsigned char *a,

 		       const int prefixlen)

 {

   IPAddressOrRanges *aors = make_prefix_or_range(addr, afi, safi);

   IPAddressOrRange *aor;

   if (aors == NULL || !make_addressPrefix(&aor, a, prefixlen))

     return 0;

   if (sk_IPAddressOrRange_push(aors, aor))

     return 1;

   IPAddressOrRange_free(aor);

   return 0;

 }

 /*

  * Add a range.

  */

 int v3_addr_add_range(IPAddrBlocks *addr,

 		      const unsigned afi,

 		      const unsigned *safi,

 		      unsigned char *min,

 		      unsigned char *max)

 {

   IPAddressOrRanges *aors = make_prefix_or_range(addr, afi, safi);

   IPAddressOrRange *aor;

   int length = length_from_afi(afi);

   if (aors == NULL)

     return 0;

   if (!make_addressRange(&aor, min, max, length))

     return 0;

   if (sk_IPAddressOrRange_push(aors, aor))

     return 1;

   IPAddressOrRange_free(aor);

   return 0;

 }

 /*

  * Extract min and max values from an IPAddressOrRange.

  */

 static void extract_min_max(IPAddressOrRange *aor,

 			    unsigned char *min,

 			    unsigned char *max,

 			    int length)

 {

   assert(aor != NULL && min != NULL && max != NULL);

   switch (aor->type) {

   case IPAddressOrRange_addressPrefix:

     addr_expand(min, aor->u.addressPrefix, length, 0x00);

     addr_expand(max, aor->u.addressPrefix, length, 0xFF);

     return;

   case IPAddressOrRange_addressRange:

     addr_expand(min, aor->u.addressRange->min, length, 0x00);

     addr_expand(max, aor->u.addressRange->max, length, 0xFF);

     return;

   }

 }

 /*

  * Public wrapper for extract_min_max().

  */

 int v3_addr_get_range(IPAddressOrRange *aor,

 		      const unsigned afi,

 		      unsigned char *min,

 		      unsigned char *max,

 		      const int length)

 {

   int afi_length = length_from_afi(afi);

   if (aor == NULL || min == NULL || max == NULL ||

       afi_length == 0 || length < afi_length ||

       (aor->type != IPAddressOrRange_addressPrefix &&

        aor->type != IPAddressOrRange_addressRange))

     return 0;

   extract_min_max(aor, min, max, afi_length);

   return afi_length;

 }

 /*

  * Sort comparision function for a sequence of IPAddressFamily.

  *

  * The last paragraph of RFC 3779 2.2.3.3 is slightly ambiguous about

  * the ordering: I can read it as meaning that IPv6 without a SAFI

  * comes before IPv4 with a SAFI, which seems pretty weird.  The

  * examples in appendix B suggest that the author intended the

  * null-SAFI rule to apply only within a single AFI, which is what I

  * would have expected and is what the following code implements.

  */

 static int IPAddressFamily_cmp(const IPAddressFamily * const *a_,

 			       const IPAddressFamily * const *b_)

 {

   const ASN1_OCTET_STRING *a = (*a_)->addressFamily;

   const ASN1_OCTET_STRING *b = (*b_)->addressFamily;

   int len = ((a->length <= b->length) ? a->length : b->length);

   int cmp = memcmp(a->data, b->data, len);

   return cmp ? cmp : a->length - b->length;

 }

 /*

  * Check whether an IPAddrBLocks is in canonical form.

  */

 int v3_addr_is_canonical(IPAddrBlocks *addr)

 {

   unsigned char a_min[ADDR_RAW_BUF_LEN], a_max[ADDR_RAW_BUF_LEN];

   unsigned char b_min[ADDR_RAW_BUF_LEN], b_max[ADDR_RAW_BUF_LEN];

   IPAddressOrRanges *aors;

   int i, j, k;

   /*

    * Empty extension is cannonical.

    */

   if (addr == NULL)

     return 1;

   /*

    * Check whether the top-level list is in order.

    */

   for (i = 0; i < sk_IPAddressFamily_num(addr) - 1; i++) {

     const IPAddressFamily *a = sk_IPAddressFamily_value(addr, i);

     const IPAddressFamily *b = sk_IPAddressFamily_value(addr, i + 1);

     if (IPAddressFamily_cmp(&a, &b) >= 0)

       return 0;

   }

   /*

    * Top level's ok, now check each address family.

    */

   for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {

     IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);

     int length = length_from_afi(v3_addr_get_afi(f));

     /*

      * Inheritance is canonical.  Anything other than inheritance or

      * a SEQUENCE OF IPAddressOrRange is an ASN.1 error or something.

      */

     if (f == NULL || f->ipAddressChoice == NULL)

       return 0;

     switch (f->ipAddressChoice->type) {

     case IPAddressChoice_inherit:

       continue;

     case IPAddressChoice_addressesOrRanges:

       break;

     default:

       return 0;

     }

     /*

      * It's an IPAddressOrRanges sequence, check it.

      */

     aors = f->ipAddressChoice->u.addressesOrRanges;

     if (sk_IPAddressOrRange_num(aors) == 0)

       return 0;

     for (j = 0; j < sk_IPAddressOrRange_num(aors) - 1; j++) {

       IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, j);

       IPAddressOrRange *b = sk_IPAddressOrRange_value(aors, j + 1);

       extract_min_max(a, a_min, a_max, length);

       extract_min_max(b, b_min, b_max, length);

       /*

        * Punt misordered list, overlapping start, or inverted range.

        */

       if (memcmp(a_min, b_min, length) >= 0 ||

 	  memcmp(a_min, a_max, length) > 0 ||

 	  memcmp(b_min, b_max, length) > 0)

 	return 0;

       /*

        * Punt if adjacent or overlapping.  Check for adjacency by

        * subtracting one from b_min first.

        */

       for (k = length - 1; k >= 0 && b_min[k]-- == 0x00; k--)

 	;

       if (memcmp(a_max, b_min, length) >= 0)

 	return 0;

       /*

        * Check for range that should be expressed as a prefix.

        */

       if (a->type == IPAddressOrRange_addressRange &&

 	  range_should_be_prefix(a_min, a_max, length) >= 0)

 	return 0;

     }

     /*

      * Check final range to see if it should be a prefix.

      */

     j = sk_IPAddressOrRange_num(aors) - 1;

     {

       IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, j);

       if (a->type == IPAddressOrRange_addressRange) {

 	extract_min_max(a, a_min, a_max, length);

 	if (range_should_be_prefix(a_min, a_max, length) >= 0)

 	  return 0;

       }

     }

   }

   /*

    * If we made it through all that, we're happy.

    */

   return 1;

 }

 /*

  * Whack an IPAddressOrRanges into canonical form.

  */

 static int IPAddressOrRanges_canonize(IPAddressOrRanges *aors,

 				      const unsigned afi)

 {

   int i, j, length = length_from_afi(afi);

   /*

    * Sort the IPAddressOrRanges sequence.

    */

   sk_IPAddressOrRange_sort(aors);

   /*

    * Clean up representation issues, punt on duplicates or overlaps.

    */

   for (i = 0; i < sk_IPAddressOrRange_num(aors) - 1; i++) {

     IPAddressOrRange *a = sk_IPAddressOrRange_value(aors, i);

     IPAddressOrRange *b = sk_IPAddressOrRange_value(aors, i + 1);

     unsigned char a_min[ADDR_RAW_BUF_LEN], a_max[ADDR_RAW_BUF_LEN];

     unsigned char b_min[ADDR_RAW_BUF_LEN], b_max[ADDR_RAW_BUF_LEN];

     extract_min_max(a, a_min, a_max, length);

     extract_min_max(b, b_min, b_max, length);

     /*

      * Punt overlaps.

      */

     if (memcmp(a_max, b_min, length) >= 0)

       return 0;

     /*

      * Merge if a and b are adjacent.  We check for

      * adjacency by subtracting one from b_min first.

      */

     for (j = length - 1; j >= 0 && b_min[j]-- == 0x00; j--)

       ;

     if (memcmp(a_max, b_min, length) == 0) {

       IPAddressOrRange *merged;

       if (!make_addressRange(&merged, a_min, b_max, length))

 	return 0;

       sk_IPAddressOrRange_set(aors, i, merged);

       sk_IPAddressOrRange_delete(aors, i + 1);

       IPAddressOrRange_free(a);

       IPAddressOrRange_free(b);

       --i;

       continue;

     }

   }

   return 1;

 }

 /*

  * Whack an IPAddrBlocks extension into canonical form.

  */

 int v3_addr_canonize(IPAddrBlocks *addr)

 {

   int i;

   for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {

     IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);

     if (f->ipAddressChoice->type == IPAddressChoice_addressesOrRanges &&

 	!IPAddressOrRanges_canonize(f->ipAddressChoice->u.addressesOrRanges,

 				    v3_addr_get_afi(f)))

       return 0;

   }

   sk_IPAddressFamily_sort(addr);

   assert(v3_addr_is_canonical(addr));

   return 1;

 }

 /*

  * v2i handler for the IPAddrBlocks extension.

  */

 static void *v2i_IPAddrBlocks(struct v3_ext_method *method,

 			      struct v3_ext_ctx *ctx,

 			      STACK_OF(CONF_VALUE) *values)

 {

   static const char v4addr_chars[] = "0123456789.";

   static const char v6addr_chars[] = "0123456789.:abcdefABCDEF";

   IPAddrBlocks *addr = NULL;

   char *s = NULL, *t;

   int i;

   if ((addr = sk_IPAddressFamily_new(IPAddressFamily_cmp)) == NULL) {

     X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);

     return NULL;

   }

   for (i = 0; i < sk_CONF_VALUE_num(values); i++) {

     CONF_VALUE *val = sk_CONF_VALUE_value(values, i);

     unsigned char min[ADDR_RAW_BUF_LEN], max[ADDR_RAW_BUF_LEN];

     unsigned afi, *safi = NULL, safi_;

     const char *addr_chars;

     int prefixlen, i1, i2, delim, length;

     if (       !name_cmp(val->name, "IPv4")) {

       afi = IANA_AFI_IPV4;

     } else if (!name_cmp(val->name, "IPv6")) {

       afi = IANA_AFI_IPV6;

     } else if (!name_cmp(val->name, "IPv4-SAFI")) {

       afi = IANA_AFI_IPV4;

       safi = &safi_;

     } else if (!name_cmp(val->name, "IPv6-SAFI")) {

       afi = IANA_AFI_IPV6;

       safi = &safi_;

     } else {

       X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_EXTENSION_NAME_ERROR);

       X509V3_conf_err(val);

       goto err;

     }

     switch (afi) {

     case IANA_AFI_IPV4:

       addr_chars = v4addr_chars;

       break;

     case IANA_AFI_IPV6:

       addr_chars = v6addr_chars;

       break;

     }

     length = length_from_afi(afi);

     /*

      * Handle SAFI, if any, and BUF_strdup() so we can null-terminate

      * the other input values.

      */

     if (safi != NULL) {

       *safi = strtoul(val->value, &t, 0);

       t += strspn(t, " \t");

       if (*safi > 0xFF || *t++ != ':') {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_SAFI);

 	X509V3_conf_err(val);

 	goto err;

       }

       t += strspn(t, " \t");

       s = BUF_strdup(t);

     } else {

       s = BUF_strdup(val->value);

     }

     if (s == NULL) {

       X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);

       goto err;

     }

     /*

      * Check for inheritance.  Not worth additional complexity to

      * optimize this (seldom-used) case.

      */

     if (!strcmp(s, "inherit")) {

       if (!v3_addr_add_inherit(addr, afi, safi)) {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_INHERITANCE);

 	X509V3_conf_err(val);

 	goto err;

       }

       OPENSSL_free(s);

       s = NULL;

       continue;

     }

     i1 = strspn(s, addr_chars);

     i2 = i1 + strspn(s + i1, " \t");

     delim = s[i2++];

     s[i1] = '\0';

     if (a2i_ipadd(min, s) != length) {

       X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_IPADDRESS);

       X509V3_conf_err(val);

       goto err;

     }

     switch (delim) {

     case '/':

       prefixlen = (int) strtoul(s + i2, &t, 10);

       if (t == s + i2 || *t != '\0') {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_EXTENSION_VALUE_ERROR);

 	X509V3_conf_err(val);

 	goto err;

       }

       if (!v3_addr_add_prefix(addr, afi, safi, min, prefixlen)) {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);

 	goto err;

       }

       break;

     case '-':

       i1 = i2 + strspn(s + i2, " \t");

       i2 = i1 + strspn(s + i1, addr_chars);

       if (i1 == i2 || s[i2] != '\0') {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_EXTENSION_VALUE_ERROR);

 	X509V3_conf_err(val);

 	goto err;

       }

       if (a2i_ipadd(max, s + i1) != length) {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_INVALID_IPADDRESS);

 	X509V3_conf_err(val);

 	goto err;

       }

       if (!v3_addr_add_range(addr, afi, safi, min, max)) {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);

 	goto err;

       }

       break;

     case '\0':

       if (!v3_addr_add_prefix(addr, afi, safi, min, length * 8)) {

 	X509V3err(X509V3_F_V2I_IPADDRBLOCKS, ERR_R_MALLOC_FAILURE);

 	goto err;

       }

       break;

     default:

       X509V3err(X509V3_F_V2I_IPADDRBLOCKS, X509V3_R_EXTENSION_VALUE_ERROR);

       X509V3_conf_err(val);

       goto err;

     }

     OPENSSL_free(s);

     s = NULL;

   }

   /*

    * Canonize the result, then we're done.

    */

   if (!v3_addr_canonize(addr))

     goto err;    

   return addr;

  err:

   OPENSSL_free(s);

   sk_IPAddressFamily_pop_free(addr, IPAddressFamily_free);

   return NULL;

 }

 /*

  * OpenSSL dispatch

  */

 const X509V3_EXT_METHOD v3_addr = {

   NID_sbgp_ipAddrBlock,		/* nid */

   0,				/* flags */

   ASN1_ITEM_ref(IPAddrBlocks),	/* template */

   0, 0, 0, 0,			/* old functions, ignored */

   0,				/* i2s */

   0,				/* s2i */

   0,				/* i2v */

   v2i_IPAddrBlocks,		/* v2i */

   i2r_IPAddrBlocks,		/* i2r */

   0,				/* r2i */

   NULL				/* extension-specific data */

 };

 /*

  * Figure out whether extension sues inheritance.

  */

 int v3_addr_inherits(IPAddrBlocks *addr)

 {

   int i;

   if (addr == NULL)

     return 0;

   for (i = 0; i < sk_IPAddressFamily_num(addr); i++) {

     IPAddressFamily *f = sk_IPAddressFamily_value(addr, i);

     if (f->ipAddressChoice->type == IPAddressChoice_inherit)

       return 1;

   }

   return 0;

 }

 /*

  * Figure out whether parent contains child.

  */

 static int addr_contains(IPAddressOrRanges *parent,

 			 IPAddressOrRanges *child,

 			 int length)

 {

   unsigned char p_min[ADDR_RAW_BUF_LEN], p_max[ADDR_RAW_BUF_LEN];

   unsigned char c_min[ADDR_RAW_BUF_LEN], c_max[ADDR_RAW_BUF_LEN];

   int p, c;

   if (child == NULL || parent == child)

     return 1;

   if (parent == NULL)

     return 0;

   p = 0;

   for (c = 0; c < sk_IPAddressOrRange_num(child); c++) {

     extract_min_max(sk_IPAddressOrRange_value(child, c),

 		    c_min, c_max, length);

     for (;; p++) {

       if (p >= sk_IPAddressOrRange_num(parent))

 	return 0;

       extract_min_max(sk_IPAddressOrRange_value(parent, p),

 		      p_min, p_max, length);

       if (memcmp(p_max, c_max, length) < 0)

 	continue;

       if (memcmp(p_min, c_min, length) > 0)

 	return 0;

       break;

     }

   }

   return 1;

 }

 /*

  * Test whether a is a subset of b.

  */

 int v3_addr_subset(IPAddrBlocks *a, IPAddrBlocks *b)

 {

   int i;

   if (a == NULL || a == b)

     return 1;

   if (b == NULL || v3_addr_inherits(a) || v3_addr_inherits(b))

     return 0;

   sk_IPAddressFamily_set_cmp_func(b, IPAddressFamily_cmp);

   for (i = 0; i < sk_IPAddressFamily_num(a); i++) {

     IPAddressFamily *fa = sk_IPAddressFamily_value(a, i);

     int j = sk_IPAddressFamily_find(b, fa);

     IPAddressFamily *fb = sk_IPAddressFamily_value(b, j);

     if (!addr_contains(fb->ipAddressChoice->u.addressesOrRanges, 

 		       fa->ipAddressChoice->u.addressesOrRanges,

 		       length_from_afi(v3_addr_get_afi(fb))))

       return 0;

   }

   return 1;

 }

 /*

  * Validation error handling via callback.

  */

 #define validation_err(_err_)		\

   do {					\

     if (ctx != NULL) {			\

       ctx->error = _err_;		\

       ctx->error_depth = i;		\

       ctx->current_cert = x;		\

       ret = ctx->verify_cb(0, ctx);	\

     } else {				\

       ret = 0;				\

     }					\

     if (!ret)				\

       goto done;			\

   } while (0)

 /*

  * Core code for RFC 3779 2.3 path validation.

  */

 static int v3_addr_validate_path_internal(X509_STORE_CTX *ctx,

 					  STACK_OF(X509) *chain,

 					  IPAddrBlocks *ext)

 {

   IPAddrBlocks *child = NULL;

   int i, j, ret = 1;

   X509 *x = NULL;

   assert(chain != NULL && sk_X509_num(chain) > 0);

   assert(ctx != NULL || ext != NULL);

   assert(ctx == NULL || ctx->verify_cb != NULL);

   /*

    * Figure out where to start.  If we don't have an extension to

    * check, we're done.  Otherwise, check canonical form and

    * set up for walking up the chain.

    */

   if (ext != NULL) {

     i = -1;

   } else {

     i = 0;

     x = sk_X509_value(chain, i);

     assert(x != NULL);

     if ((ext = x->rfc3779_addr) == NULL)

       goto done;

   }

   if (!v3_addr_is_canonical(ext))

     validation_err(X509_V_ERR_INVALID_EXTENSION);

   sk_IPAddressFamily_set_cmp_func(ext, IPAddressFamily_cmp);

   if ((child = sk_IPAddressFamily_dup(ext)) == NULL) {

     X509V3err(X509V3_F_V3_ADDR_VALIDATE_PATH_INTERNAL, ERR_R_MALLOC_FAILURE);

     ret = 0;

     goto done;

   }

   /*

    * Now walk up the chain.  No cert may list resources that its

    * parent doesn't list.

    */

   for (i++; i < sk_X509_num(chain); i++) {

     x = sk_X509_value(chain, i);

     assert(x != NULL);

     if (!v3_addr_is_canonical(x->rfc3779_addr))

       validation_err(X509_V_ERR_INVALID_EXTENSION);

     if (x->rfc3779_addr == NULL) {

       for (j = 0; j < sk_IPAddressFamily_num(child); j++) {

 	IPAddressFamily *fc = sk_IPAddressFamily_value(child, j);

 	if (fc->ipAddressChoice->type != IPAddressChoice_inherit) {

 	  validation_err(X509_V_ERR_UNNESTED_RESOURCE);

 	  break;

 	}

       }

       continue;

     }

     sk_IPAddressFamily_set_cmp_func(x->rfc3779_addr, IPAddressFamily_cmp);

     for (j = 0; j < sk_IPAddressFamily_num(child); j++) {

       IPAddressFamily *fc = sk_IPAddressFamily_value(child, j);

       int k = sk_IPAddressFamily_find(x->rfc3779_addr, fc);

       IPAddressFamily *fp = sk_IPAddressFamily_value(x->rfc3779_addr, k);

       if (fp == NULL) {

 	if (fc->ipAddressChoice->type == IPAddressChoice_addressesOrRanges) {

 	  validation_err(X509_V_ERR_UNNESTED_RESOURCE);

 	  break;

 	}

 	continue;

       }

       if (fp->ipAddressChoice->type == IPAddressChoice_addressesOrRanges) {

 	if (fc->ipAddressChoice->type == IPAddressChoice_inherit ||

 	    addr_contains(fp->ipAddressChoice->u.addressesOrRanges, 

 			  fc->ipAddressChoice->u.addressesOrRanges,

 			  length_from_afi(v3_addr_get_afi(fc))))

 	  sk_IPAddressFamily_set(child, j, fp);

 	else

 	  validation_err(X509_V_ERR_UNNESTED_RESOURCE);

       }

     }

   }

   /*

    * Trust anchor can't inherit.

    */

   if (x->rfc3779_addr != NULL) {

     for (j = 0; j < sk_IPAddressFamily_num(x->rfc3779_addr); j++) {

       IPAddressFamily *fp = sk_IPAddressFamily_value(x->rfc3779_addr, j);

       if (fp->ipAddressChoice->type == IPAddressChoice_inherit &&

 	  sk_IPAddressFamily_find(child, fp) >= 0)

 	validation_err(X509_V_ERR_UNNESTED_RESOURCE);

     }

   }

  done:

   sk_IPAddressFamily_free(child);

   return ret;

 }

 #undef validation_err

 /*

  * RFC 3779 2.3 path validation -- called from X509_verify_cert().

  */

 int v3_addr_validate_path(X509_STORE_CTX *ctx)

 {

   return v3_addr_validate_path_internal(ctx, ctx->chain, NULL);

 }

 /*

  * RFC 3779 2.3 path validation of an extension.

  * Test whether chain covers extension.

  */

 int v3_addr_validate_resource_set(STACK_OF(X509) *chain,

 				  IPAddrBlocks *ext,

 				  int allow_inheritance)

 {

   if (ext == NULL)

     return 1;

   if (chain == NULL || sk_X509_num(chain) == 0)

     return 0;

   if (!allow_inheritance && v3_addr_inherits(ext))

     return 0;

   return v3_addr_validate_path_internal(NULL, chain, ext);

 }

 #endif /* OPENSSL_NO_RFC3779 */