pceplib/pcep_msg_encoding.h

   1 /*
   2  * This file is part of the PCEPlib, a PCEP protocol library.
   3  *
   4  * Copyright (C) 2020 Volta Networks https://voltanet.io/
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  18  *
  19  * Author : Brady Johnson <brady@voltanet.io>
  20  *
  21  */
  22
  23
  24 /*
  25  * Definitions for encoding and decoding PCEP messages, objects, and TLVs.
  26  */
  27
  28 #ifndef PCEP_ENCODING_H
  29 #define PCEP_ENCODING_H
  30
  31 #include <stdbool.h>
  32
  33 #include "pcep_msg_messages.h"
  34 #include "pcep_msg_objects.h"
  35 #include "pcep_msg_tlvs.h"
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 struct pcep_versioning {
  42         bool draft_ietf_pce_segment_routing_07; /* If false, use draft16 */
  43         /* As more draft versions are incorporated, add appropriate attributes
  44          */
  45 };
  46
  47 #define MESSAGE_HEADER_LENGTH 4
  48 #define PCEP_MESSAGE_LENGTH 65535
  49 #define OBJECT_HEADER_LENGTH 4
  50 #define OBJECT_RO_SUBOBJ_HEADER_LENGTH 2
  51 #define TLV_HEADER_LENGTH 4
  52 #define LENGTH_1WORD sizeof(uint32_t)
  53 #define LENGTH_2WORDS sizeof(uint32_t) * 2
  54 #define LENGTH_3WORDS sizeof(uint32_t) * 3
  55 #define LENGTH_4WORDS sizeof(uint32_t) * 4
  56 #define LENGTH_5WORDS sizeof(uint32_t) * 5
  57 #define LENGTH_6WORDS sizeof(uint32_t) * 6
  58 #define LENGTH_7WORDS sizeof(uint32_t) * 7
  59 #define LENGTH_8WORDS sizeof(uint32_t) * 8
  60 #define LENGTH_9WORDS sizeof(uint32_t) * 9
  61 #define LENGTH_10WORDS sizeof(uint32_t) * 10
  62 #define LENGTH_11WORDS sizeof(uint32_t) * 11
  63 #define LENGTH_12WORDS sizeof(uint32_t) * 12
  64 #define LENGTH_13WORDS sizeof(uint32_t) * 13
  65
  66 /* When iterating sub-objects or TLVs, limit to 10 in case corrupt data is
  67  * received */
  68 #define MAX_ITERATIONS 10
  69
  70 struct pcep_versioning *create_default_pcep_versioning(void);
  71 void destroy_pcep_versioning(struct pcep_versioning *versioning);
  72
  73 /*
  74  * Message encoding / decoding functions
  75  */
  76
  77 /* Called before sending messages to encode the message to a byte buffer in
  78  * Network byte order. This function will also encode all the objects and their
  79  * TLVs in the message. The result will be stored in the encoded_message field
  80  * in the pcep_message. Implemented in pcep-messages-encoding.c */
  81 void pcep_encode_message(struct pcep_message *message,
  82                          struct pcep_versioning *versioning);
  83
  84 /* Decode the message header and return the message length.
  85  * Returns < 0 for invalid message headers. */
  86 int32_t pcep_decode_validate_msg_header(const uint8_t *msg_buf);
  87
  88 /* Decode the entire message */
  89 struct pcep_message *pcep_decode_message(const uint8_t *message_buffer);
  90
  91
  92 /*
  93  * Object encoding / decoding functions
  94  */
  95
  96 /* Implemented in pcep-objects-encoding.c
  97  * Encode the object in struct pcep_object_header* into the uint8_t *buf,
  98  * and return the encoded object_length. */
  99 uint16_t pcep_encode_object(struct pcep_object_header *object_hdr,
 100                             struct pcep_versioning *versioning, uint8_t *buf);
 101
 102 /* Implemented in pcep-objects-encoding.c
 103  * Decode the object, including the TLVs (if any) and return the object.
 104  * Returns object on success, NULL otherwise. */
 105 struct pcep_object_header *pcep_decode_object(const uint8_t *msg_buf);
 106
 107 /* Internal util functions implemented in pcep-objects-encoding.c */
 108 void encode_ipv6(struct in6_addr *src_ipv6, uint32_t *dst);
 109 void decode_ipv6(const uint32_t *src, struct in6_addr *dst_ipv6);
 110 uint16_t normalize_pcep_tlv_length(uint16_t length);
 111 bool pcep_object_has_tlvs(struct pcep_object_header *object_hdr);
 112 uint16_t pcep_object_get_length_by_hdr(struct pcep_object_header *object_hdr);
 113 uint16_t pcep_object_get_length(enum pcep_object_classes object_class,
 114                                 enum pcep_object_types object_type);
 115
 116
 117 /*
 118  * TLV encoding / decoding functions
 119  */
 120
 121 /* Implemented in pcep-tlv-encoding.c
 122  * Encode the tlv in struct pcep_tlv_header* into the uint8_t *buf,
 123  * and return the encoded tlv_length. */
 124 uint16_t pcep_encode_tlv(struct pcep_object_tlv_header *tlv_hdr,
 125                          struct pcep_versioning *versioning, uint8_t *buf);
 126
 127 /* Decode the TLV in tlv_buf and return a pointer to the object */
 128 struct pcep_object_tlv_header *pcep_decode_tlv(const uint8_t *tlv_buf);
 129
 130
 131 /*
 132  * utils mainly for testing purposes
 133  */
 134 bool validate_message_objects(struct pcep_message *msg);
 135
 136 #ifdef __cplusplus
 137 }
 138 #endif
 139
 140 #endif