v3_addr.c

OpenSSL 0.9.8k 最新版OpenSSL

/*
 * 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
 *    [e-mail].
 *
 * 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
 * ([e-mail]).  This product includes software written by Tim
 * Hudson ([e-mail]).
 */

/*
 * Implementation of RFC 3779 section 2.2.
 */

#include <stdio.h>
#include <stdlib.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 int 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)
{
  OPENSSL_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, ":");
    if (i == 0)
      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 int 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;
  }