libcoap  4.3.0rc2
coap_pdu_internal.h
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1 /*
2  * coap_pdu_internal.h -- CoAP PDU structure
3  *
4  * Copyright (C) 2010-2021 Olaf Bergmann <bergmann@tzi.org>
5  *
6  * This file is part of the CoAP library libcoap. Please see README for terms
7  * of use.
8  */
9 
15 #ifndef COAP_COAP_PDU_INTERNAL_H_
16 #define COAP_COAP_PDU_INTERNAL_H_
17 
18 #ifdef WITH_LWIP
19 #include <lwip/pbuf.h>
20 #endif
21 
22 #include <stdint.h>
23 
31 #define COAP_DEFAULT_VERSION 1 /* version of CoAP supported */
32 
33 /* TCP Message format constants, do not modify */
34 #define COAP_MESSAGE_SIZE_OFFSET_TCP8 13
35 #define COAP_MESSAGE_SIZE_OFFSET_TCP16 269 /* 13 + 256 */
36 #define COAP_MESSAGE_SIZE_OFFSET_TCP32 65805 /* 269 + 65536 */
37 
38 /* Derived message size limits */
39 #define COAP_MAX_MESSAGE_SIZE_TCP0 (COAP_MESSAGE_SIZE_OFFSET_TCP8-1) /* 12 */
40 #define COAP_MAX_MESSAGE_SIZE_TCP8 (COAP_MESSAGE_SIZE_OFFSET_TCP16-1) /* 268 */
41 #define COAP_MAX_MESSAGE_SIZE_TCP16 (COAP_MESSAGE_SIZE_OFFSET_TCP32-1) /* 65804 */
42 #define COAP_MAX_MESSAGE_SIZE_TCP32 (COAP_MESSAGE_SIZE_OFFSET_TCP32+0xFFFFFFFF)
43 
44 #ifndef COAP_DEBUG_BUF_SIZE
45 #if defined(WITH_CONTIKI) || defined(WITH_LWIP)
46 #define COAP_DEBUG_BUF_SIZE 128
47 #else /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
48 /* 1024 derived from RFC7252 4.6. Message Size max payload */
49 #define COAP_DEBUG_BUF_SIZE (8 + 1024 * 2)
50 #endif /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
51 #endif /* COAP_DEBUG_BUF_SIZE */
52 
53 #ifndef COAP_DEFAULT_MAX_PDU_RX_SIZE
54 #if defined(WITH_CONTIKI) || defined(WITH_LWIP)
55 #define COAP_DEFAULT_MAX_PDU_RX_SIZE (COAP_MAX_MESSAGE_SIZE_TCP16+4UL)
56 #else
57 /* 8 MiB max-message-size plus some space for options */
58 #define COAP_DEFAULT_MAX_PDU_RX_SIZE (8UL*1024*1024+256)
59 #endif
60 #endif /* COAP_DEFAULT_MAX_PDU_RX_SIZE */
61 
66 #define COAP_DROPPED_RESPONSE -2
67 
68 #define COAP_PDU_DELAYED -3
69 
70 #define COAP_PAYLOAD_START 0xFF /* payload marker */
71 
72 #define COAP_PDU_IS_EMPTY(pdu) ((pdu)->code == 0)
73 #define COAP_PDU_IS_REQUEST(pdu) (!COAP_PDU_IS_EMPTY(pdu) && (pdu)->code < 32)
74 #define COAP_PDU_IS_RESPONSE(pdu) ((pdu)->code >= 64 && (pdu)->code < 224)
75 #define COAP_PDU_IS_SIGNALING(pdu) ((pdu)->code >= 224)
76 
77 #define COAP_PDU_MAX_UDP_HEADER_SIZE 4
78 #define COAP_PDU_MAX_TCP_HEADER_SIZE 6
79 
92 struct coap_pdu_t {
98  uint8_t max_hdr_size;
99  uint8_t hdr_size;
101  uint8_t token_length;
102  uint16_t max_opt;
103  size_t alloc_size;
105  size_t used_size;
107  size_t max_size;
109  uint8_t *token;
110  uint8_t *data;
111 #ifdef WITH_LWIP
112  struct pbuf *pbuf;
120 #endif
121  const uint8_t *body_data;
122  size_t body_length;
123  size_t body_offset;
124  size_t body_total;
127 };
128 
138 int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size);
139 
149 int coap_pdu_check_resize(coap_pdu_t *pdu, size_t new_size);
150 
161  const uint8_t *data);
162 
174 size_t coap_pdu_parse_size(coap_proto_t proto,
175  const uint8_t *data,
176  size_t length);
177 
186 
199 
214 int coap_pdu_parse(coap_proto_t proto,
215  const uint8_t *data,
216  size_t length,
217  coap_pdu_t *pdu);
218 
228 void coap_pdu_clear(coap_pdu_t *pdu, size_t size);
229 
239 
253  size_t len, const uint8_t *data);
254 
266 size_t coap_update_option(coap_pdu_t *pdu,
267  coap_option_num_t number,
268  size_t len,
269  const uint8_t *data);
270 
281 
293  size_t len,
294  const uint8_t *data);
295 
298 #endif /* COAP_COAP_PDU_INTERNAL_H_ */
size_t coap_insert_option(coap_pdu_t *pdu, coap_option_num_t number, size_t len, const uint8_t *data)
Inserts option of given number in the pdu with the appropriate data.
Definition: pdu.c:412
int coap_remove_option(coap_pdu_t *pdu, coap_option_num_t number)
Removes (first) option of given number from the pdu.
Definition: pdu.c:312
int coap_update_token(coap_pdu_t *pdu, size_t len, const uint8_t *data)
Updates token in pdu with length len and data.
Definition: pdu.c:280
int coap_pdu_parse_header(coap_pdu_t *pdu, coap_proto_t proto)
Decode the protocol specific header for the specified PDU.
Definition: pdu.c:823
size_t coap_pdu_parse_header_size(coap_proto_t proto, const uint8_t *data)
Interprets data to determine the number of bytes in the header.
Definition: pdu.c:768
void coap_pdu_clear(coap_pdu_t *pdu, size_t size)
Clears any contents from pdu and resets used_size, and data pointers.
Definition: pdu.c:35
int coap_pdu_parse_opt(coap_pdu_t *pdu)
Verify consistency in the given CoAP PDU structure and locate the data.
Definition: pdu.c:975
size_t coap_update_option(coap_pdu_t *pdu, coap_option_num_t number, size_t len, const uint8_t *data)
Updates existing first option of given number in the pdu with the new data.
Definition: pdu.c:501
size_t coap_pdu_encode_header(coap_pdu_t *pdu, coap_proto_t proto)
Compose the protocol specific header for the specified PDU.
Definition: pdu.c:1125
int coap_pdu_parse(coap_proto_t proto, const uint8_t *data, size_t length, coap_pdu_t *pdu)
Parses data into the CoAP PDU structure given in result.
Definition: pdu.c:1100
int coap_pdu_check_resize(coap_pdu_t *pdu, size_t new_size)
Dynamically grows the size of pdu to new_size if needed.
Definition: pdu.c:239
size_t coap_pdu_parse_size(coap_proto_t proto, const uint8_t *data, size_t length)
Parses data to extract the message size.
Definition: pdu.c:791
int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size)
Dynamically grows the size of pdu to new_size.
Definition: pdu.c:205
int coap_mid_t
coap_mid_t is used to store the CoAP Message ID of a CoAP PDU.
Definition: pdu.h:229
coap_proto_t
CoAP protocol types.
Definition: pdu.h:278
coap_pdu_code_t
Set of codes available for a PDU.
Definition: pdu.h:289
coap_pdu_type_t
CoAP PDU message type definitions.
Definition: pdu.h:54
uint16_t coap_option_num_t
Definition: option.h:20
Structure to hold large body (many blocks) transmission information.
structure for CoAP PDUs token, if any, follows the fixed size header, then options until payload mark...
uint8_t max_hdr_size
space reserved for protocol-specific header
uint16_t max_opt
highest option number in PDU
uint8_t * token
first byte of token, if any, or options
coap_lg_xmit_t * lg_xmit
Holds ptr to lg_xmit if sending a set of blocks.
size_t body_length
Holds body data length.
size_t max_size
maximum size for token, options and payload, or zero for variable size pdu
const uint8_t * body_data
Holds ptr to re-assembled data or NULL.
size_t body_offset
Holds body data offset.
coap_pdu_code_t code
request method (value 1–31) or response code (value 64-255)
uint8_t token_length
length of Token
uint8_t hdr_size
actual size used for protocol-specific header
uint8_t * data
first byte of payload, if any
coap_mid_t mid
message id, if any, in regular host byte order
size_t used_size
used bytes of storage for token, options and payload
size_t alloc_size
allocated storage for token, options and payload
size_t body_total
Holds body data total size.
coap_pdu_type_t type
message type