pceplib/pcep_msg_encoding.h

   1 // SPDX-License-Identifier: LGPL-2.1-or-later
   2 /*
   3  * This file is part of the PCEPlib, a PCEP protocol library.
   4  *
   5  * Copyright (C) 2020 Volta Networks https://voltanet.io/
   6  *
   7  * Author : Brady Johnson <brady@voltanet.io>
   8  *
   9  */
  10
  11
  12 /*
  13  * Definitions for encoding and decoding PCEP messages, objects, and TLVs.
  14  */
  15
  16 #ifndef PCEP_ENCODING_H
  17 #define PCEP_ENCODING_H
  18
  19 #include <stdbool.h>
  20
  21 #include "pcep_msg_messages.h"
  22 #include "pcep_msg_objects.h"
  23 #include "pcep_msg_tlvs.h"
  24
  25 #ifdef __cplusplus
  26 extern "C" {
  27 #endif
  28
  29 struct pcep_versioning {
  30         bool draft_ietf_pce_segment_routing_07; /* If false, use draft16 */
  31         /* As more draft versions are incorporated, add appropriate attributes
  32          */
  33 };
  34
  35 #define MESSAGE_HEADER_LENGTH 4
  36 #define PCEP_MESSAGE_LENGTH 65535
  37 #define OBJECT_HEADER_LENGTH 4
  38 #define OBJECT_RO_SUBOBJ_HEADER_LENGTH 2
  39 #define TLV_HEADER_LENGTH 4
  40 #define LENGTH_1WORD sizeof(uint32_t)
  41 #define LENGTH_2WORDS sizeof(uint32_t) * 2
  42 #define LENGTH_3WORDS sizeof(uint32_t) * 3
  43 #define LENGTH_4WORDS sizeof(uint32_t) * 4
  44 #define LENGTH_5WORDS sizeof(uint32_t) * 5
  45 #define LENGTH_6WORDS sizeof(uint32_t) * 6
  46 #define LENGTH_7WORDS sizeof(uint32_t) * 7
  47 #define LENGTH_8WORDS sizeof(uint32_t) * 8
  48 #define LENGTH_9WORDS sizeof(uint32_t) * 9
  49 #define LENGTH_10WORDS sizeof(uint32_t) * 10
  50 #define LENGTH_11WORDS sizeof(uint32_t) * 11
  51 #define LENGTH_12WORDS sizeof(uint32_t) * 12
  52 #define LENGTH_13WORDS sizeof(uint32_t) * 13
  53
  54 /* When iterating sub-objects or TLVs, limit to 10 in case corrupt data is
  55  * received */
  56 #define MAX_ITERATIONS 10
  57
  58 struct pcep_versioning *create_default_pcep_versioning(void);
  59 void destroy_pcep_versioning(struct pcep_versioning *versioning);
  60
  61 /*
  62  * Message encoding / decoding functions
  63  */
  64
  65 /* Called before sending messages to encode the message to a byte buffer in
  66  * Network byte order. This function will also encode all the objects and their
  67  * TLVs in the message. The result will be stored in the encoded_message field
  68  * in the pcep_message. Implemented in pcep-messages-encoding.c */
  69 void pcep_encode_message(struct pcep_message *message,
  70                          struct pcep_versioning *versioning);
  71
  72 /* Decode the message header and return the message length.
  73  * Returns < 0 for invalid message headers. */
  74 int32_t pcep_decode_validate_msg_header(const uint8_t *msg_buf);
  75
  76 /* Decode the entire message */
  77 struct pcep_message *pcep_decode_message(const uint8_t *message_buffer);
  78
  79
  80 /*
  81  * Object encoding / decoding functions
  82  */
  83
  84 /* Implemented in pcep-objects-encoding.c
  85  * Encode the object in struct pcep_object_header* into the uint8_t *buf,
  86  * and return the encoded object_length. */
  87 uint16_t pcep_encode_object(struct pcep_object_header *object_hdr,
  88                             struct pcep_versioning *versioning, uint8_t *buf);
  89
  90 /* Implemented in pcep-objects-encoding.c
  91  * Decode the object, including the TLVs (if any) and return the object.
  92  * Returns object on success, NULL otherwise. */
  93 struct pcep_object_header *pcep_decode_object(const uint8_t *msg_buf);
  94
  95 /* Internal util functions implemented in pcep-objects-encoding.c */
  96 void encode_ipv6(struct in6_addr *src_ipv6, uint32_t *dst);
  97 void decode_ipv6(const uint32_t *src, struct in6_addr *dst_ipv6);
  98 uint16_t normalize_pcep_tlv_length(uint16_t length);
  99 bool pcep_object_has_tlvs(struct pcep_object_header *object_hdr);
 100 uint16_t pcep_object_get_length_by_hdr(struct pcep_object_header *object_hdr);
 101 uint16_t pcep_object_get_length(enum pcep_object_classes object_class,
 102                                 enum pcep_object_types object_type);
 103
 104
 105 /*
 106  * TLV encoding / decoding functions
 107  */
 108
 109 /* Implemented in pcep-tlv-encoding.c
 110  * Encode the tlv in struct pcep_tlv_header* into the uint8_t *buf,
 111  * and return the encoded tlv_length. */
 112 uint16_t pcep_encode_tlv(struct pcep_object_tlv_header *tlv_hdr,
 113                          struct pcep_versioning *versioning, uint8_t *buf);
 114
 115 /* Decode the TLV in tlv_buf and return a pointer to the object */
 116 struct pcep_object_tlv_header *pcep_decode_tlv(const uint8_t *tlv_buf);
 117
 118
 119 /*
 120  * utils mainly for testing purposes
 121  */
 122 bool validate_message_objects(struct pcep_message *msg);
 123
 124 #ifdef __cplusplus
 125 }
 126 #endif
 127
 128 #endif