/*

 * 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;

  }