libcoap  4.3.1
coap_pdu_internal.h
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1 /*
2  * coap_pdu_internal.h -- CoAP PDU structure
3  *
4  * Copyright (C) 2010-2022 Olaf Bergmann <bergmann@tzi.org>
5  *
6  * SPDX-License-Identifier: BSD-2-Clause
7  *
8  * This file is part of the CoAP library libcoap. Please see README for terms
9  * of use.
10  */
11 
17 #ifndef COAP_COAP_PDU_INTERNAL_H_
18 #define COAP_COAP_PDU_INTERNAL_H_
19 
20 #include "coap_internal.h"
21 
22 #ifdef WITH_LWIP
23 #include <lwip/pbuf.h>
24 #endif
25 
26 #include <stdint.h>
27 
35 #define COAP_DEFAULT_VERSION 1 /* version of CoAP supported */
36 
37 /* TCP Message format constants, do not modify */
38 #define COAP_MESSAGE_SIZE_OFFSET_TCP8 13
39 #define COAP_MESSAGE_SIZE_OFFSET_TCP16 269 /* 13 + 256 */
40 #define COAP_MESSAGE_SIZE_OFFSET_TCP32 65805 /* 269 + 65536 */
41 
42 /* Derived message size limits */
43 #define COAP_MAX_MESSAGE_SIZE_TCP0 (COAP_MESSAGE_SIZE_OFFSET_TCP8-1) /* 12 */
44 #define COAP_MAX_MESSAGE_SIZE_TCP8 (COAP_MESSAGE_SIZE_OFFSET_TCP16-1) /* 268 */
45 #define COAP_MAX_MESSAGE_SIZE_TCP16 (COAP_MESSAGE_SIZE_OFFSET_TCP32-1) /* 65804 */
46 #define COAP_MAX_MESSAGE_SIZE_TCP32 (COAP_MESSAGE_SIZE_OFFSET_TCP32+0xFFFFFFFF)
47 
48 #ifndef COAP_DEBUG_BUF_SIZE
49 #if defined(WITH_CONTIKI) || defined(WITH_LWIP)
50 #define COAP_DEBUG_BUF_SIZE 128
51 #else /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
52 /* 1024 derived from RFC7252 4.6. Message Size max payload */
53 #define COAP_DEBUG_BUF_SIZE (8 + 1024 * 2)
54 #endif /* defined(WITH_CONTIKI) || defined(WITH_LWIP) */
55 #endif /* COAP_DEBUG_BUF_SIZE */
56 
57 #ifndef COAP_DEFAULT_MAX_PDU_RX_SIZE
58 #if defined(WITH_CONTIKI) || defined(WITH_LWIP)
59 #define COAP_DEFAULT_MAX_PDU_RX_SIZE (COAP_MAX_MESSAGE_SIZE_TCP16+4UL)
60 #else
61 /* 8 MiB max-message-size plus some space for options */
62 #define COAP_DEFAULT_MAX_PDU_RX_SIZE (8UL*1024*1024+256)
63 #endif
64 #endif /* COAP_DEFAULT_MAX_PDU_RX_SIZE */
65 
70 #define COAP_DROPPED_RESPONSE -2
71 
72 #define COAP_PDU_DELAYED -3
73 
74 #define COAP_PAYLOAD_START 0xFF /* payload marker */
75 
76 #define COAP_PDU_IS_EMPTY(pdu) ((pdu)->code == 0)
77 #define COAP_PDU_IS_REQUEST(pdu) (!COAP_PDU_IS_EMPTY(pdu) && (pdu)->code < 32)
78 #define COAP_PDU_IS_RESPONSE(pdu) ((pdu)->code >= 64 && (pdu)->code < 224)
79 #define COAP_PDU_IS_SIGNALING(pdu) ((pdu)->code >= 224)
80 
81 #define COAP_PDU_MAX_UDP_HEADER_SIZE 4
82 #define COAP_PDU_MAX_TCP_HEADER_SIZE 6
83 
106 struct coap_pdu_t {
112  uint8_t max_hdr_size;
113  uint8_t hdr_size;
115  uint8_t token_length;
116  uint8_t crit_opt;
117  uint16_t max_opt;
118  size_t alloc_size;
120  size_t used_size;
122  size_t max_size;
124  uint8_t *token;
125  uint8_t *data;
126 #ifdef WITH_LWIP
127  struct pbuf *pbuf;
135 #endif
136  const uint8_t *body_data;
137  size_t body_length;
138  size_t body_offset;
139  size_t body_total;
142 };
143 
153 int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size);
154 
164 int coap_pdu_check_resize(coap_pdu_t *pdu, size_t new_size);
165 
176  const uint8_t *data);
177 
189 size_t coap_pdu_parse_size(coap_proto_t proto,
190  const uint8_t *data,
191  size_t length);
192 
201 
214 
224 void coap_pdu_clear(coap_pdu_t *pdu, size_t size);
225 
247  coap_option_num_t number,
248  size_t len,
249  const uint8_t *data);
259 
273  size_t len, const uint8_t *data);
274 
286 size_t coap_update_option(coap_pdu_t *pdu,
287  coap_option_num_t number,
288  size_t len,
289  const uint8_t *data);
290 
301 
313  size_t len,
314  const uint8_t *data);
315 
318 #endif /* COAP_COAP_PDU_INTERNAL_H_ */
Pulls together all the internal only header files.
uint16_t coap_option_num_t
Definition: coap_option.h:20
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:477
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:333
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:299
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:884
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:829
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:48
int coap_pdu_parse_opt(coap_pdu_t *pdu)
Verify consistency in the given CoAP PDU structure and locate the data.
Definition: pdu.c:1038
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:565
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:1188
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:258
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:852
int coap_pdu_resize(coap_pdu_t *pdu, size_t new_size)
Dynamically grows the size of pdu to new_size.
Definition: pdu.c:223
size_t coap_add_option_internal(coap_pdu_t *pdu, coap_option_num_t number, size_t len, const uint8_t *data)
Adds option of given number to pdu that is passed as first parameter.
Definition: pdu.c:615
int coap_mid_t
coap_mid_t is used to store the CoAP Message ID of a CoAP PDU.
Definition: pdu.h:243
coap_proto_t
CoAP protocol types.
Definition: pdu.h:292
coap_pdu_code_t
Set of codes available for a PDU.
Definition: pdu.h:303
coap_pdu_type_t
CoAP PDU message type definitions.
Definition: pdu.h:60
Structure to hold large body (many blocks) transmission information.
structure for CoAP PDUs
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 (0 until header is encoded)
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
uint8_t crit_opt
Set if unknown critical option for proxy.
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