/*

 *   This library is free software; you can redistribute it and/or

 *   modify it under the terms of the GNU Lesser General Public

 *   License as published by the Free Software Foundation; either

 *   version 2.1 of the License, or (at your option) any later version.

 *

 *   This library is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY; without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

 *   Lesser General Public License for more details.

 *

 *   You should have received a copy of the GNU Lesser General Public

 *   License along with this library; if not, write to the Free Software

 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA

 */

/**

 * $Id: b1ea167299a685e0a27776663cbedc1f91b58187 $

 *

 * @file protocols/dhcpv4/decode.c

 * @brief Functions to decode DHCP options.

 *

 * @copyright 2008,2017 The FreeRADIUS server project

 * @copyright 2008 Alan DeKok (aland@deployingradius.com)

 * @copyright 2015,2017 Arran Cudbard-Bell (a.cudbardb@freeradius.org)

 */

#include <freeradius-devel/io/test_point.h>

#include <freeradius-devel/util/proto.h>

#include <freeradius-devel/util/struct.h>

#include <freeradius-devel/util/dns.h>

#include "dhcpv4.h"

#include "attrs.h"

static _Thread_local uint8_t  concat_buffer[1500]; /* ethernet max */

static ssize_t decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,

            fr_dict_attr_t const *parent,

            uint8_t const *data, size_t const data_len, void *decode_ctx);

static bool verify_tlvs(uint8_t const *data, size_t data_len)

{

  uint8_t const *p = data;

  uint8_t const *end = data + data_len;

  while (p < end) {

    if ((end - p) < 2) return false;

    if ((p + p[1]) > end) return false;

    p += 2 + p[1];

  }

  return true;

}

static ssize_t decode_tlv_trampoline(TALLOC_CTX *ctx, fr_pair_list_t *out,

             fr_dict_attr_t const *parent,

             uint8_t const *data, size_t const data_len, void *decode_ctx)

{

  return fr_pair_tlvs_from_network(ctx, out, parent, data, data_len, decode_ctx, decode_option, verify_tlvs, true);

}

static ssize_t decode_value(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dict_attr_t const *parent,

          uint8_t const *data, size_t data_len, void *decode_ctx);

/** Handle arrays of DNS labels for fr_struct_from_network()

 *

 */

static ssize_t decode_value_trampoline(TALLOC_CTX *ctx, fr_pair_list_t *out,

               fr_dict_attr_t const *parent,

               uint8_t const *data, size_t const data_len, void *decode_ctx)

{

  FR_PROTO_TRACE("decode_value_trampoline of %s with %zu bytes", parent->name, data_len);

  /*

   *  @todo - we might need to limit this to only one DNS label.

   */

  if ((parent->type == FR_TYPE_STRING) && fr_dhcpv4_flag_dns_label(parent)) {

    return fr_pair_dns_labels_from_network(ctx, out, parent, data, data, data_len, NULL, false);

  }

  return decode_value(ctx, out, parent, data, data_len, decode_ctx);

}

/*

 *  Decode ONE value into a VP

 */

static ssize_t decode_value(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dict_attr_t const *da,

          uint8_t const *data, size_t data_len, void *decode_ctx)

{

  ssize_t slen;

  fr_pair_t *vp;

  uint8_t const *p = data;

  uint8_t const *end = data + data_len;

  bool exact = !da->flags.array;

  FR_PROTO_TRACE("%s called to parse %zu bytes from %s", __FUNCTION__, data_len, da->name);

  FR_PROTO_HEX_DUMP(data, data_len, NULL);

  /*

   *  Structs create their own VP wrapper.

   */

  if (da->type == FR_TYPE_STRUCT) {

    slen = fr_struct_from_network(ctx, out, da, data, data_len,

                decode_ctx, decode_value_trampoline, decode_tlv_trampoline);

    if (slen < 0) return slen;

    if (!exact) return slen;

    return data_len;

  }

  /*

   *  These are always raw.

   */

  if (da->flags.is_unknown) {

    return fr_pair_raw_from_network(ctx, out, da, data, data_len);

  }

  vp = fr_pair_afrom_da(ctx, da);

  if (!vp) return PAIR_DECODE_OOM;

  PAIR_ALLOCED(vp);

  /*

   *  string / octets / bool can be empty.  Other data types are

   *  raw if they're empty.

   */

  if (data_len == 0) {

    if (da->type == FR_TYPE_BOOL) {

      vp->vp_bool = true;

      goto finish;

    }

    if ((da->type == FR_TYPE_OCTETS) || (da->type == FR_TYPE_STRING)) {

      goto finish;

    }

    talloc_free(vp);

    return fr_pair_raw_from_network(ctx, out, da, data, 0);

  }

  switch (vp->vp_type) {

  case FR_TYPE_ATTR:

    /*

     *  Force the length of the data to be one,

     *  otherwise the "from network" call complains.

     *  Because we pass in the enumv as the _parent_

     *  and not the da.  The da is marked as "array",

     *  but the parent is not.

     */

    end = p + 1;

    fr_assert(da->parent->flags.is_root);

    slen = fr_value_box_from_network(vp, &vp->data, vp->vp_type, da->parent,

             &FR_DBUFF_TMP(p, end - p), end - p, true);

    if (slen <= 0) goto raw;

    p++;

    break;

  /*

   *  Doesn't include scope, whereas the generic format can.

   */

  case FR_TYPE_IPV6_ADDR:

    slen = fr_value_box_ipaddr_from_network(&vp->data, da->type, da,

              128, p, (size_t) (end - p),

              exact, true);

    if (slen < 0) goto raw;

    fr_assert(slen == sizeof(vp->vp_ipv6addr));

    p += sizeof(vp->vp_ipv6addr);

    break;

  case FR_TYPE_IPV6_PREFIX:

    /*

     *  Not enough room for the prefix length, that's an issue.

     *

     *  Note that there's actually no standard for IPv6 prefixes inside of DHCPv4.

     */

    if ((end - p) < 1) goto raw;

    slen = fr_value_box_ipaddr_from_network(&vp->data, da->type, da,

              p[0], p + 1, ((size_t) (end - p)) - 1,

              exact, true);

    if (slen < 0) goto raw;

    p += slen + 1;

    break;

  case FR_TYPE_STRUCTURAL:

    fr_strerror_printf("Cannot decode type '%s' as value", fr_type_to_str(vp->vp_type));

    talloc_free(vp);

    return 0;

  case FR_TYPE_IPV4_PREFIX:

    fr_value_box_init(&vp->data, FR_TYPE_IPV4_PREFIX, vp->da, true);

    vp->vp_ip.af = AF_INET;

    /*

     *  4 octets of address

     *  4 octets of mask

     */

    if (fr_dhcpv4_flag_prefix_split(da)) {

      uint32_t ipaddr, mask;

      if (data_len < 8) goto raw;

      ipaddr = fr_nbo_to_uint32(p);

      mask = fr_nbo_to_uint32(p + 4);

      p += 8;

      /*

       *  0/0 means a prefix of 0, too.

       */

      if (!mask) {

        break;

      }

      /*

       *  Try to figure out the prefix value from the mask.

       */

      while (mask) {

        vp->vp_ip.prefix++;

        mask <<= 1;

      }

      /*

       *  Mash the IP based on the calculated mask.  We don't really care if the mask

       *  has holes, or if the IP address overlaps with the mask.  We just fix it all up

       *  so it's sane.

       */

      mask = ~(uint32_t) 0;

      mask <<= (32 - vp->vp_ip.prefix);

      vp->vp_ipv4addr = htonl(ipaddr & mask);

      break;

    }

    if (fr_dhcpv4_flag_prefix_bits(vp->da)) {

      size_t needs;

      if ((data_len == 0) || (*p > 32)) goto raw;

      needs = 1 + ((*p + 0x07) >> 3);

      if (data_len < needs) goto raw;

      /*

       *  Don't do exact checks here, as the content is variable-sized.

       */

      vp->vp_ip.prefix = *p;

      /*

       *  If the IP address is longer than necessary, then only grab the pieces we need.

       */

      if (vp->vp_ip.prefix) {

        uint32_t ipaddr, mask;

        mask = ~(uint32_t) 0;

        mask <<= (32 - vp->vp_ip.prefix);

        if (*p > 24) {

          ipaddr = fr_nbo_to_uint32(p + 1);

        } else if (*p > 16) {

          ipaddr = fr_nbo_to_uint24(p + 1);

          ipaddr <<= 8;

        } else if (*p > 8) {

          ipaddr = fr_nbo_to_uint16(p + 1);

          ipaddr <<= 16;

        } else { /* 1..8 */

          ipaddr = p[1];

          ipaddr <<= 24;

        }

        vp->vp_ipv4addr = htonl(ipaddr & mask);

      } /* else *p==0, and we leave ipaddr set to zero */

      p += needs;

      break;

    }

    FALL_THROUGH;

  default:

    slen = fr_value_box_from_network(vp, &vp->data, vp->vp_type, da,

             &FR_DBUFF_TMP(p, end - p), end - p, true);

    if (slen < 0) {

    raw:

      FR_PROTO_TRACE("decoding as unknown type");

      if (fr_pair_raw_afrom_pair(vp, p, (end - p)) < 0) {

        return -1;

      }

      p = end;

      break;

    }

    if (exact && (slen != (end - p))) {

      goto raw;

    }

    p += (size_t) slen;

    break;

  }

finish:

  FR_PROTO_TRACE("decoding value complete, adding new pair and returning %zu byte(s)", (size_t) (p - data));

  fr_pair_append(out, vp);

  return p - data;

}

/** RFC 4243 Vendor Specific Suboptions

 *

 * Vendor specific suboptions are in the format.

 @verbatim

      0                   1                   2                   3

      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     |                     Enterprise Number 0                       |

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     |    Len 0      |                                               /

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     /                      Suboption Data 0                         /

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     |                     Enterprise Number n                       |

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     |    Len n      |                                               /

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     /                      Suboption Data n                         /

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 @endverbatim

 *

 * So although the vendor is identified, the format of the data isn't

 * specified so we can't actually resolve the suboption to an

 * attribute.  For now, we just convert it to an attribute of

 * Vendor-Specific-Information with raw octets contents.

 */

/*

 *  One VSA option may contain multiple vendors, each vendor

 *  may contain one or more sub-options.

 *

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 *  |  option-code  |  option-len   |

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 *  |      enterprise-number1       |

 *  |                               |

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 *  |   data-len1   |               |

 *  +-+-+-+-+-+-+-+-+ option-data1  |

 *  /                               /

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ----

 *  |      enterprise-number2       |   ^

 *  |                               |   |

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |

 *  |   data-len2   |               | optional

 *  +-+-+-+-+-+-+-+-+ option-data2  |   |

 *  /                               /   |

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |

 *  ~            ...                ~   V

 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ----

 */

static ssize_t decode_vsa(TALLOC_CTX *ctx, fr_pair_list_t *out, fr_dict_attr_t const *parent,

        uint8_t const *data, size_t const data_len, void *decode_ctx)

{

  ssize_t     len;

  uint8_t     option_len;

  uint32_t    pen;

  fr_pair_t   *vp;

  fr_dict_attr_t const  *vendor;

  uint8_t const   *end = data + data_len;

  uint8_t const   *p = data;

  FR_PROTO_HEX_DUMP(data, data_len, "decode_vsa");

  if (!fr_cond_assert_msg(parent->type == FR_TYPE_VSA,

        "%s: Internal sanity check failed, attribute \"%s\" is not of type 'vsa'",

        __FUNCTION__, parent->name)) return PAIR_DECODE_FATAL_ERROR;

next:

  /*

   *  We need at least 4 (PEN) + 1 (data-len) + 1 (vendor option num) to be able to decode vendor

   *  specific attributes.  If we don't have that, then we return an error.  The caller will free

   *  the VSA, and create a "raw.VSA" attribute.

   */

  if ((size_t)(end - p) < (sizeof(uint32_t) + 1 + 1)) {

    return -1;

  }

  pen = fr_nbo_to_uint32(p);

  /*

   *  Verify that the parent (which should be a VSA)

   *  contains a fake attribute representing the vendor.

   *

   *  If it doesn't then this vendor is unknown, but we know

   *  vendor attributes have a standard format, so we can

   *  decode the data anyway.

   */

  vendor = fr_dict_attr_child_by_num(parent, pen);

  if (!vendor) {

    fr_dict_attr_t *n;

    n = fr_dict_attr_unknown_vendor_afrom_num(ctx, parent, pen);

    if (!n) return PAIR_DECODE_OOM;

    vendor = n;

  }

  p += sizeof(uint32_t);

  FR_PROTO_TRACE("decode context %s -> %s", parent->name, vendor->name);

  option_len = p[0];

  if ((p + 1 + option_len) > end) {

    len = fr_pair_raw_from_network(ctx, out, vendor, p, end - p);

    if (len < 0) return len;

    return data_len + 2; /* decoded the whole thing */

  }

  p++;

  /*

   *  Pathological case of no data.

   */

  if (option_len == 0) goto next;

  vp = fr_pair_find_by_da(out, NULL, vendor);

  if (!vp) {

    vp = fr_pair_afrom_da(ctx, vendor);

    if (!vp) return PAIR_DECODE_FATAL_ERROR;

    PAIR_ALLOCED(vp);

    fr_pair_append(out, vp);

  }

  len = fr_pair_tlvs_from_network(vp, &vp->vp_group, vendor, p, option_len, decode_ctx, decode_option, verify_tlvs, false);

  if (len < 0) return len;

  p += option_len;

  if (p < end) goto next;

  /*

   *  Tell the caller we read all of it, even if we didn't.

   */

  return data_len + 2;

}

static ssize_t decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,

            fr_dict_attr_t const *parent,

            uint8_t const *data, size_t const data_len, void *decode_ctx)

{

  unsigned int      option;

  size_t      len;

  ssize_t     slen;

  fr_dict_attr_t const  *da;

  fr_dhcpv4_ctx_t   *packet_ctx = decode_ctx;

#ifdef STATIC_ANALYZER

  if (!packet_ctx || !packet_ctx->tmp_ctx) return PAIR_DECODE_FATAL_ERROR;

#endif

  fr_assert(parent != NULL);

  /*

   *      RFC 3046 is very specific about not allowing termination

   *      with a 255 sub-option. But it's required for decoding

   *      option 43, and vendors will probably screw it up

   *      anyway.

   *

   *      Similarly, option 0 is sometimes treated as

   *      "end of options".

   *

   *  @todo - this check is likely correct only when at the

   *  dhcpv4 root, OR inside of option 43.  It could be

   *  argued that it's wrong for all other TLVs.

   */

  if ((data_len == 1) && ((data[0] == 0) || (data[1] == 255))) return data_len;

  /*

   *  Must have at least an option header.

   */

  if (data_len < 2) {

    fr_strerror_printf("%s: Insufficient data", __FUNCTION__);

    return -(data_len);

  }

  option = data[0];

  len = data[1];

  if (len > (data_len - 2)) {

    fr_strerror_printf("%s: Option overflows input.  "

           "Optional length must be less than %zu bytes, got %zu bytes",

           __FUNCTION__, data_len - 2, len);

    return PAIR_DECODE_FATAL_ERROR;

  }

  da = fr_dict_attr_child_by_num(parent, option);

  if (!da) {

    da = fr_dict_attr_unknown_raw_afrom_num(packet_ctx->tmp_ctx, parent, option);

    if (!da) return PAIR_DECODE_OOM;

    slen = fr_pair_raw_from_network(ctx, out, da, data + 2, len);

  } else if ((da->type == FR_TYPE_STRING) && fr_dhcpv4_flag_dns_label(da)) {

    slen = fr_pair_dns_labels_from_network(ctx, out, da, data + 2, data + 2, len, NULL, true);

  } else if (da->flags.array) {

    slen = fr_pair_array_from_network(ctx, out, da, data + 2, len, decode_ctx, decode_value);

  } else if (da->type == FR_TYPE_VSA) {

    bool append = false;

    fr_pair_t *vp;

    vp = fr_pair_find_by_da(out, NULL, da);

    if (!vp) {

      vp = fr_pair_afrom_da(ctx, da);

      if (!vp) return PAIR_DECODE_FATAL_ERROR;

      PAIR_ALLOCED(vp);

      append = true;

    }

    slen = decode_vsa(vp, &vp->vp_group, da, data + 2, len, decode_ctx);

    if (append) {

      if (slen < 0) {

        TALLOC_FREE(vp);

      } else {

        fr_pair_append(out, vp);

      }

    }

  } else if (da->type == FR_TYPE_TLV) {

    slen = fr_pair_tlvs_from_network(ctx, out, da, data + 2, len, decode_ctx, decode_option, verify_tlvs, true);

  } else {

    slen = decode_value(ctx, out, da, data + 2, len, decode_ctx);

  }

  if (slen < 0) {

    slen = fr_pair_raw_from_network(ctx, out, da, data + 2, len);

    if (slen < 0) return slen;

  }

  return len + 2;

}

/** Decode DHCP option

 *

 * @param[in] ctx context to alloc new attributes in.

 * @param[out] out    Where to write the decoded options.

 * @param[in] data    to parse.

 * @param[in] data_len    of data to parse.

 * @param[in] decode_ctx  Unused.

 */

ssize_t fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_pair_list_t *out,

              uint8_t const *data, size_t data_len, void *decode_ctx)

{

  ssize_t     slen;

  uint8_t const   *p = data, *end = data + data_len;

  uint8_t const   *next;

  fr_dhcpv4_ctx_t   *packet_ctx = decode_ctx;

  FR_PROTO_TRACE("%s called to parse %zu byte(s)", __FUNCTION__, data_len);

  if (data_len == 0) return 0;

  FR_PROTO_HEX_DUMP(data, data_len, NULL);

  /*

   *  Padding / End of options

   */

  if (p[0] == 0) {     /* 0x00 - Padding option    */

    data_len = 1;     /* Walk over any consecutive 0x00 */

    p++;        /* for efficiency     */

    while ((p < end) && (p[0] == 0)) {

      p++;

      data_len ++;

    }

    return data_len;

  }

  if (p[0] == 255) return data_len;  /* 0xff - End of options signifier */

  /*

   *  Everything else should be real options

   */

  if ((data_len < 2) || ((size_t) (data[1] + 2) > data_len)) {

    fr_strerror_printf("%s: Insufficient data", __FUNCTION__);

    return -1;

  }

  /*

   *  Check for multiple options of the same type, and concatenate their values together.

   *

   *  RFC 2131 Section 4.1 says:

   *

   *    The client concatenates the values of multiple

   *    instances of the same option into a single parameter

   *    list for configuration.

   *

   *  which presumably also means the same for the server on reception.

   *

   *  We therefore peek ahead, and concatenate the values into a temporary buffer.  The buffer is

   *  allocated only if necessary, and is re-used for the entire packet.

   *

   *  If the options are *not* consecutive, then we don't concatenate them.  Too bad for you!

   *

   *  Note that we don't (yet) do this for TLVs.

   */

  next = data + 2 + data[1];

  if ((data[1] > 0) && (next < end) && (next[0] == data[0])) {

    uint8_t *q;

    fr_dict_attr_t const *da;

    q = concat_buffer;

    for (next = data; next < end; next += 2 + next[1]) {

      if (next >= end) return -1;

      if (next[0] != data[0]) break;

      if ((end - next) < 2) return -1;

      if ((next + 2 + next[1]) > end) return -1;

      if ((size_t) (q + next[1] - concat_buffer) > sizeof(concat_buffer)) return -1;

      memcpy(q, next + 2, next[1]);

      q += next[1];

    }

    if (q == concat_buffer) return 0;

    da = fr_dict_attr_child_by_num(packet_ctx->root, p[0]);

    if (!da) {

      da = fr_dict_attr_unknown_raw_afrom_num(packet_ctx->tmp_ctx, packet_ctx->root, p[0]);

      if (!da) return -1;

      slen = fr_pair_raw_from_network(ctx, out, da, concat_buffer, q - concat_buffer);

    } else if (da->type == FR_TYPE_VSA) {

      slen = decode_vsa(ctx, out, da, concat_buffer, q - concat_buffer, packet_ctx);

    } else if (da->type == FR_TYPE_TLV) {

      slen = fr_pair_tlvs_from_network(ctx, out, da, concat_buffer, q - concat_buffer,

               packet_ctx, decode_option, verify_tlvs, true);

    } else if (da->flags.array) {

      slen = fr_pair_array_from_network(ctx, out, da, concat_buffer, q - concat_buffer, packet_ctx, decode_value);

    } else {

      slen = decode_value(ctx, out, da, concat_buffer, q - concat_buffer, packet_ctx);

    }

    if (slen < 0) return slen;

    /*

     *  The actual amount of data we decoded, including the various headers.

     */

    FR_PROTO_TRACE("decoding option complete, %zd decoded, returning %zu byte(s)", slen, (size_t) (next - data));

    return next - data;

  }

  slen = decode_option(ctx, out, packet_ctx->root, data, data[1] + 2, decode_ctx);

  if (slen < 0) return slen;

  FR_PROTO_TRACE("decoding option complete, %zd decoded, returning %u byte(s)", slen, (unsigned int) data[1] + 2);

  return data[1] + 2;

}

ssize_t fr_dhcpv4_decode_foreign(TALLOC_CTX *ctx, fr_pair_list_t *out,

         uint8_t const *data, size_t data_len)

{

  ssize_t slen;

  uint8_t const *attr, *end;

  fr_dhcpv4_ctx_t decode_ctx = {

    .root = fr_dict_root(dict_dhcpv4)

  };

  fr_assert(dict_dhcpv4 != NULL);

  decode_ctx.tmp_ctx = talloc(ctx, uint8_t);

  attr = data;

  end = data + data_len;

  while (attr < end) {

    slen = fr_dhcpv4_decode_option(ctx, out, attr, (end - attr), &decode_ctx);

    if (slen < 0) {

      talloc_free(decode_ctx.tmp_ctx);

      return slen;

    }

    /*

     *  If slen is larger than the room in the packet,

     *  all kinds of bad things happen.

     */

     if (!fr_cond_assert(slen <= (end - attr))) {

      talloc_free(decode_ctx.tmp_ctx);

       return -slen - (attr - data);

     }

    attr += slen;

    talloc_free_children(decode_ctx.tmp_ctx);

  }

  talloc_free(decode_ctx.tmp_ctx);

  return data_len;

}

static int decode_test_ctx(void **out, TALLOC_CTX *ctx, UNUSED fr_dict_t const *dict,

         fr_dict_attr_t const *root_da)

{

  fr_dhcpv4_ctx_t *test_ctx;

  test_ctx = talloc_zero(ctx, fr_dhcpv4_ctx_t);

  test_ctx->tmp_ctx = talloc(test_ctx, uint8_t);

  test_ctx->root = root_da ? root_da : fr_dict_root(dict_dhcpv4);

  *out = test_ctx;

  return 0;

}

static ssize_t fr_dhcpv4_decode_proto(TALLOC_CTX *ctx, fr_pair_list_t *out,

              uint8_t const *data, size_t data_len, UNUSED void *proto_ctx)

{

  unsigned int  code;

  if (!fr_dhcpv4_ok(data, data_len, NULL, NULL)) return -1;

  if (fr_dhcpv4_decode(ctx, out, data, data_len, &code) < 0) return -1;

  return data_len;

}

static ssize_t decode_option_wrapper(TALLOC_CTX *ctx, fr_pair_list_t *out, NDEBUG_UNUSED fr_dict_attr_t const *parent,

              uint8_t const *data, size_t data_len, void *decode_ctx)

{

  fr_assert(parent == fr_dict_root(dict_dhcpv4));

  return fr_dhcpv4_decode_option(ctx, out, data, data_len, decode_ctx);

}

/*

 *  Test points

 */

extern fr_test_point_pair_decode_t dhcpv4_tp_decode_pair;

fr_test_point_pair_decode_t dhcpv4_tp_decode_pair = {

  .test_ctx = decode_test_ctx,

  .func   = decode_option_wrapper

};

extern fr_test_point_proto_decode_t dhcpv4_tp_decode_proto;

fr_test_point_proto_decode_t dhcpv4_tp_decode_proto = {

  .test_ctx = decode_test_ctx,

  .func   = fr_dhcpv4_decode_proto

};