#pragma once

/*

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

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program 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 General Public License for more details.

 *

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

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

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

 */

/**

 * $Id: ca83b3b34a2820892bacf25f49188a296447dbd2 $

 *

 * @file protocols/dns/dns.h

 * @brief Implementation of the DNS protocol.

 *

 * @copyright 2021 Network RADIUS SAS (legal@networkradius.com)

 */

RCSIDH(protocols_dns_h, "$Id: ca83b3b34a2820892bacf25f49188a296447dbd2 $")

#ifdef __cplusplus

extern "C" {

#endif

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

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

#define DNS_MAX_ATTRIBUTES  255

typedef struct {

  uint16_t  id;

#ifdef WORDS_BIGENDIAN

  unsigned int  query     : 1;

  unsigned int  opcode      : 4;

  unsigned int  authoritative   : 1;

  unsigned int  truncated   : 1;

  unsigned int  recursion_desired : 1;

#else

  unsigned int  recursion_desired : 1;

  unsigned int  truncated   : 1;

  unsigned int  authoritative   : 1;

  unsigned int  opcode      : 4;

  unsigned int  query     : 1;

#endif

#ifdef WORDS_BIGENDIAN

  unsigned int  recursion_available : 1;

  unsigned int  reserved    : 1;

  unsigned int  authentic_data    : 1;

  unsigned int  checking_disabled : 1;

  unsigned int  rcode     : 4;

#else

  unsigned int  rcode     : 4;

  unsigned int  checking_disabled : 1;

  unsigned int  authentic_data    : 1;

  unsigned int  reserved    : 1;

  unsigned int  recursion_available : 1;

#endif

  uint16_t  qdcount;

  uint16_t  ancount;

  uint16_t  nscount;

  uint16_t  arcount;

} CC_HINT(__packed__) fr_dns_packet_t;

typedef struct {

  TALLOC_CTX    *tmp_ctx;   //!< for temporary things cleaned up during decoding

  uint8_t const   *packet;    //!< DNS labels can point anywhere in the packet :(

  size_t      packet_len;

  fr_dns_labels_t   *lb;

} fr_dns_ctx_t;

int   fr_dns_global_init(void);

void    fr_dns_global_free(void);

typedef enum {

  FR_DNS_QUERY = 0,

  FR_DNS_INVERSE_QUERY = 1,

  FR_DNS_STATUS = 2,

  FR_DNS_NOTIFY = 4,

  FR_DNS_UPDATE = 5,

  FR_DNS_STATEFUL_OPERATION = 6,

  FR_DNS_CODE_MAX = 7,

  FR_DNS_QUERY_RESPONSE = 16,

  FR_DNS_INVERSE_QUERY_RESPONSE = 17,

  FR_DNS_STATUS_RESPONSE = 18,

  FR_DNS_NOTIFY_RESPONSE = 20,

  FR_DNS_UPDATE_RESPONSE = 21,

  FR_DNS_STATEFUL_OPERATION_RESPONSE = 22,

  FR_DNS_DO_NOT_RESPOND = 256,

} fr_dns_packet_code_t;

typedef enum {

  FR_DNS_DECODE_FAIL_NONE = 0,

  FR_DNS_DECODE_FAIL_UNKNOWN_OPCODE,

  FR_DNS_DECODE_FAIL_MIN_LENGTH_PACKET,

  FR_DNS_DECODE_FAIL_MAX_LENGTH_PACKET,

  FR_DNS_DECODE_FAIL_UNEXPECTED,

  FR_DNS_DECODE_FAIL_NO_QUESTIONS,

  FR_DNS_DECODE_FAIL_ANSWERS_IN_QUESTION,

  FR_DNS_DECODE_FAIL_NS_IN_QUESTION,

  FR_DNS_DECODE_FAIL_INVALID_RR_LABEL,

  FR_DNS_DECODE_FAIL_MISSING_RR_HEADER,

  FR_DNS_DECODE_FAIL_MISSING_RR_LEN,

  FR_DNS_DECODE_FAIL_ZERO_RR_LEN,

  FR_DNS_DECODE_FAIL_RR_OVERFLOWS_PACKET,

  FR_DNS_DECODE_FAIL_TOO_MANY_RRS,

  FR_DNS_DECODE_FAIL_TOO_FEW_RRS,

  FR_DNS_DECODE_FAIL_POINTER_TO_NON_LABEL,

  FR_DNS_DECODE_FAIL_POINTER_OVERFLOWS_PACKET,

  FR_DNS_DECODE_FAIL_POINTER_TO_HEADER,

  FR_DNS_DECODE_FAIL_POINTER_LOOPS,

  FR_DNS_DECODE_FAIL_INVALID_POINTER,

  FR_DNS_DECODE_FAIL_LABEL_OVERFLOWS_PACKET,

  FR_DNS_DECODE_FAIL_LABEL_TOO_LONG,

  FR_DNS_DECODE_FAIL_MISSING_QD_HEADER,

  FR_DNS_DECODE_FAIL_MISSING_TLV_HEADER,

  FR_DNS_DECODE_FAIL_TLV_OVERFLOWS_RR,

  FR_DNS_DECODE_FAIL_TRUNCATED,

  FR_DNS_DECODE_FAIL_MAX

} fr_dns_decode_fail_t;

#define FR_DNS_PACKET_CODE_VALID(_code) (((_code) < FR_DNS_CODE_MAX) || (((_code & 0x10) != 0) && ((_code & ~0x10) < FR_DNS_CODE_MAX)))

#define DNS_HDR_LEN (12)

typedef struct {

  bool      dns_label;

  bool      dns_label_uncompressed;

} fr_dns_attr_flags_t;

static inline fr_dns_attr_flags_t const *fr_dns_attr_flags(fr_dict_attr_t const *da)

{

  return fr_dict_attr_ext(da, FR_DICT_ATTR_EXT_PROTOCOL_SPECIFIC);

}

base.c:fr_dns_attr_flags

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162

{

143

162

  return fr_dict_attr_ext(da, FR_DICT_ATTR_EXT_PROTOCOL_SPECIFIC);

144

162

}

decode.c:fr_dns_attr_flags

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142

41.1k

{

143

41.1k

  return fr_dict_attr_ext(da, FR_DICT_ATTR_EXT_PROTOCOL_SPECIFIC);

144

41.1k

}

Unexecuted instantiation: encode.c:fr_dns_attr_flags

static inline bool fr_dns_flag_dns_label_any(fr_dict_attr_t const *da)

{

  fr_dns_attr_flags_t const *flags = fr_dns_attr_flags(da);

  return flags->dns_label || flags->dns_label_uncompressed;

}

base.c:fr_dns_flag_dns_label_any

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147

162

{

148

162

  fr_dns_attr_flags_t const *flags = fr_dns_attr_flags(da);

149

150

162

  return flags->dns_label || flags->dns_label_uncompressed;

151

162

}

Unexecuted instantiation: decode.c:fr_dns_flag_dns_label_any

Unexecuted instantiation: encode.c:fr_dns_flag_dns_label_any

#define fr_dns_flag_dns_label(_da)      (fr_dns_attr_flags(_da)->dns_label)

#define fr_dns_flag_dns_label_uncompressed(_da)   (fr_dns_attr_flags(_da)->dns_label_uncompressed)

extern fr_table_num_ordered_t fr_dns_reason_fail_table[];

extern char const *fr_dns_packet_names[FR_DNS_CODE_MAX];

extern size_t fr_dns_reason_fail_table_len;

bool fr_dns_packet_ok(uint8_t const *packet, size_t packet_len, bool query, fr_dns_decode_fail_t *reason);

fr_dns_labels_t *fr_dns_labels_get(uint8_t const *packet, size_t packet_len, bool init_mark);

ssize_t fr_dns_decode(TALLOC_CTX *ctx, fr_pair_list_t *out,

          uint8_t const *packet, size_t packet_len, fr_dns_ctx_t *packet_ctx);

ssize_t fr_dns_encode(fr_dbuff_t *dbuff, fr_pair_list_t *vps, fr_dns_ctx_t *encode_ctx);

#ifdef __cplusplus

}

#endif