Skip to content
Snippets Groups Projects
Commit dee793d2 authored by Kaspar Schleiser's avatar Kaspar Schleiser
Browse files

nanocoap: rework option handling

parent 4b210bb1
No related branches found
No related tags found
No related merge requests found
Hide whitespace changes
Inline Side-by-side
sys/include/net/nanocoap.h
+ 56
− 10
View file @ dee793d2
......@@ -47,10 +47,15 @@ extern "C" {
* @name Nanocoap specific maximum values
* @{
*/
#define NANOCOAP_URL_MAX (64)
#define NANOCOAP_QS_MAX (64)
#define NANOCOAP_NOPTS_MAX (16)
#define NANOCOAP_URI_MAX (64)
/** @} */
#ifdef MODULE_GCOAP
#define NANOCOAP_URL_MAX NANOCOAP_URI_MAX
#define NANOCOAP_QS_MAX (64)
#endif
/**
* @name CoAP option numbers
* @{
......@@ -220,14 +225,26 @@ typedef struct __attribute__((packed)) {
* @brief CoAP option array entry
*/
typedef struct {
coap_hdr_t *hdr; /**< pointer to raw packet */
uint8_t url[NANOCOAP_URL_MAX]; /**< parsed request URL */
uint8_t qs[NANOCOAP_QS_MAX]; /**< parsed query string */
uint8_t *token; /**< pointer to token */
uint8_t *payload; /**< pointer to payload */
unsigned payload_len; /**< length of payload */
uint16_t content_type; /**< content type */
uint32_t observe_value; /**< observe value */
uint16_t opt_num; /**< full CoAP option number */
uint16_t offset; /**< offset in packet */
} coap_optpos_t;
/**
* @brief CoAP PDU parsing context structure
*/
typedef struct {
coap_hdr_t *hdr; /**< pointer to raw packet */
uint8_t *token; /**< pointer to token */
uint8_t *payload; /**< pointer to payload */
uint16_t payload_len; /**< length of payload */
uint16_t options_len; /**< length of options array */
coap_optpos_t options[NANOCOAP_NOPTS_MAX]; /**< option offset array */
#ifdef MODULE_GCOAP
uint8_t url[NANOCOAP_URI_MAX]; /**< parsed request URL */
uint8_t qs[NANOCOAP_QS_MAX]; /**< parsed query string */
uint16_t content_type; /**< content type */
uint32_t observe_value; /**< observe value */
#endif
} coap_pkt_t;
/**
......@@ -392,6 +409,33 @@ size_t coap_put_option_ct(uint8_t *buf, uint16_t lastonum, uint16_t content_type
*/
size_t coap_put_option_uri(uint8_t *buf, uint16_t lastonum, const char *uri, uint16_t optnum);
/**
* @brief Get content type from packet
*
* @param[in] pkt packet to work on
*
* @returns the packet's content type value if included,
* COAP_FORMAT_NONE otherwise
*/
unsigned coap_get_content_type(coap_pkt_t *pkt);
/**
* @brief Get the packet's request URI
*
* This function decodes the pkt's URI option into a "/"-seperated and
* NULL-terminated string.
*
* Caller must ensure @p target can hold at least NANOCOAP_URI_MAX bytes!
*
* @param[in] pkt pkt to work on
* @param[out] target buffer for target URI
*
* @returns -ENOSPC if URI option is larger than NANOCOAP_URI_MAX
* @returns nr of bytes written to @p target (including '\0')
*/
int coap_get_uri(coap_pkt_t *pkt, uint8_t *target);
/**
* @brief Get the CoAP version number
*
......@@ -556,6 +600,7 @@ static inline unsigned coap_method2flag(unsigned code)
return (1 << (code - 1));
}
#if defined(MODULE_GCOAP) || defined(DOXYGEN)
/**
* @brief Identifies a packet containing an observe option
*
......@@ -590,6 +635,7 @@ static inline uint32_t coap_get_observe(coap_pkt_t *pkt)
{
return pkt->observe_value;
}
#endif
/**
* @brief Reference to the default .well-known/core handler defined by the
......
sys/net/application_layer/nanocoap/nanocoap.c
+ 191
− 59
View file @ dee793d2
/*
* Copyright (C) 2016-17 Kaspar Schleiser <kaspar@schleiser.de>
* Copyright (C) 2016-18 Kaspar Schleiser <kaspar@schleiser.de>
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
......@@ -29,7 +29,7 @@
#include "debug.h"
static int _decode_value(unsigned val, uint8_t **pkt_pos_ptr, uint8_t *pkt_end);
static uint32_t _decode_uint(uint8_t *pkt_pos, unsigned nbytes);
int coap_get_option_uint(coap_pkt_t *pkt, unsigned opt_num, uint32_t *target);
/* http://tools.ietf.org/html/rfc7252#section-3
* 0 1 2 3
......@@ -46,17 +46,14 @@ static uint32_t _decode_uint(uint8_t *pkt_pos, unsigned nbytes);
*/
int coap_parse(coap_pkt_t *pkt, uint8_t *buf, size_t len)
{
uint8_t *urlpos = pkt->url;
coap_hdr_t *hdr = (coap_hdr_t *)buf;
pkt->hdr = hdr;
uint8_t *pkt_pos = hdr->data;
uint8_t *pkt_end = buf + len;
memset(pkt->url, '\0', NANOCOAP_URL_MAX);
pkt->payload = NULL;
pkt->payload_len = 0;
pkt->observe_value = UINT32_MAX;
/* token value (tkl bytes) */
if (coap_get_token_len(pkt)) {
......@@ -67,9 +64,13 @@ int coap_parse(coap_pkt_t *pkt, uint8_t *buf, size_t len)
pkt->token = NULL;
}
coap_optpos_t *optpos = pkt->options;
unsigned option_count = 0;
unsigned option_nr = 0;
/* parse options */
int option_nr = 0;
while (pkt_pos != pkt_end) {
uint8_t *option_start = pkt_pos;
uint8_t option_byte = *pkt_pos++;
if (option_byte == 0xff) {
pkt->payload = pkt_pos;
......@@ -89,58 +90,181 @@ int coap_parse(coap_pkt_t *pkt, uint8_t *buf, size_t len)
return -EBADMSG;
}
option_nr += option_delta;
DEBUG("option nr=%i len=%i\n", option_nr, option_len);
switch (option_nr) {
case COAP_OPT_URI_HOST:
DEBUG("nanocoap: ignoring Uri-Host option!\n");
break;
case COAP_OPT_URI_PATH:
*urlpos++ = '/';
memcpy(urlpos, pkt_pos, option_len);
urlpos += option_len;
break;
case COAP_OPT_CONTENT_FORMAT:
if (option_len == 0) {
pkt->content_type = 0;
}
else if (option_len == 1) {
pkt->content_type = *pkt_pos;
}
else if (option_len == 2) {
memcpy(&pkt->content_type, pkt_pos, 2);
pkt->content_type = ntohs(pkt->content_type);
}
break;
case COAP_OPT_OBSERVE:
if (option_len < 4) {
pkt->observe_value = _decode_uint(pkt_pos, option_len);
}
else {
DEBUG("nanocoap: discarding packet with invalid option length.\n");
return -EBADMSG;
}
break;
default:
DEBUG("nanocoap: unhandled option nr=%i len=%i critical=%u\n", option_nr, option_len, option_nr & 1);
if (option_nr & 1) {
DEBUG("nanocoap: discarding packet with unknown critical option.\n");
return -EBADMSG;
}
DEBUG("option count=%u nr=%u len=%i\n", option_count, option_nr, option_len);
if (option_delta) {
optpos->opt_num = option_nr;
optpos->offset = (uintptr_t)option_start - (uintptr_t)hdr;
DEBUG("optpos option_nr=%u %u\n", (unsigned)option_nr, (unsigned)optpos->offset);
optpos++;
option_count++;
}
pkt_pos += option_len;
if (pkt_pos > (buf + len)) {
DEBUG("nanocoap: bad pkt\n");
return -EBADMSG;
}
}
}
DEBUG("coap pkt parsed. code=%u detail=%u payload_len=%u, 0x%02x\n",
pkt->options_len = option_count;
if (!pkt->payload) {
pkt->payload = pkt_pos;
}
#ifdef MODULE_GCOAP
coap_get_uri(pkt, pkt->url);
pkt->content_type = coap_get_content_type(pkt);
if (coap_get_option_uint(pkt, COAP_OPT_OBSERVE, &pkt->observe_value) != 0) {
pkt->observe_value = UINT32_MAX;
}
#endif
DEBUG("coap pkt parsed. code=%u detail=%u payload_len=%u, nopts=%u, 0x%02x\n",
coap_get_code_class(pkt),
coap_get_code_detail(pkt),
pkt->payload_len, hdr->code);
pkt->payload_len, option_count, hdr->code);
return 0;
}
uint8_t *coap_find_option(coap_pkt_t *pkt, unsigned opt_num)
{
coap_optpos_t *optpos = pkt->options;
unsigned opt_count = pkt->options_len;
while (opt_count--) {
if (optpos->opt_num == opt_num) {
return (uint8_t*)pkt->hdr + optpos->offset;
}
optpos++;
}
return NULL;
}
static uint8_t *_parse_option(coap_pkt_t *pkt, uint8_t *pkt_pos, uint16_t *delta, int *opt_len)
{
uint8_t *hdr_end = pkt->payload;
if (pkt_pos == hdr_end) {
return NULL;
}
uint8_t option_byte = *pkt_pos++;
*delta = _decode_value(option_byte >> 4, &pkt_pos, hdr_end);
*opt_len = _decode_value(option_byte & 0xf, &pkt_pos, hdr_end);
return pkt_pos;
}
static uint32_t _decode_uint(uint8_t *pkt_pos, unsigned nbytes)
{
assert(nbytes <= 4);
uint32_t res = 0;
if (nbytes) {
memcpy(((uint8_t *)&res) + (4 - nbytes), pkt_pos, nbytes);
}
return ntohl(res);
}
int coap_get_option_uint(coap_pkt_t *pkt, unsigned opt_num, uint32_t *target)
{
assert(target);
uint8_t *opt_pos = coap_find_option(pkt, opt_num);
if (opt_pos) {
uint16_t delta;
int option_len = 0;
uint8_t *pkt_pos = _parse_option(pkt, opt_pos, &delta, &option_len);
if (option_len >= 0) {
if (option_len > 4) {
DEBUG("nanocoap: uint option with len > 4 (unsupported).\n");
return -ENOSPC;
}
*target = _decode_uint(pkt_pos, option_len);
return 0;
}
else {
DEBUG("nanocoap: discarding packet with invalid option length.\n");
return -EBADMSG;
}
}
return -1;
}
uint8_t *coap_iterate_option(coap_pkt_t *pkt, uint8_t **optpos, int *opt_len, int first)
{
uint8_t *data_start;
uint16_t delta = 0;
data_start = _parse_option(pkt, *optpos, &delta, opt_len);
if (data_start && (first || !delta)) {
*optpos = data_start + *opt_len;
return data_start;
}
else {
*optpos = NULL;
return NULL;
}
}
unsigned coap_get_content_type(coap_pkt_t *pkt)
{
uint8_t *opt_pos = coap_find_option(pkt, COAP_OPT_CONTENT_FORMAT);
unsigned content_type = COAP_FORMAT_NONE;
if (opt_pos) {
uint16_t delta;
int option_len = 0;
uint8_t *pkt_pos = _parse_option(pkt, opt_pos, &delta, &option_len);
if (option_len == 0) {
content_type = 0;
} else if (option_len == 1) {
content_type = *pkt_pos;
} else if (option_len == 2) {
memcpy(&content_type, pkt_pos, 2);
content_type = ntohs(content_type);
}
}
return content_type;
}
int coap_get_uri(coap_pkt_t *pkt, uint8_t *target)
{
uint8_t *opt_pos = coap_find_option(pkt, COAP_OPT_URI_PATH);
if (!opt_pos) {
*target++ = '/';
*target = '\0';
return 2;
}
unsigned left = NANOCOAP_URI_MAX - 1;
uint8_t *part_start = NULL;
do {
int opt_len;
part_start = coap_iterate_option(pkt, &opt_pos, &opt_len, part_start==NULL);
if (part_start) {
if (left < (unsigned)(opt_len + 1)) {
return -ENOSPC;
}
*target++ = '/';
memcpy(target, part_start, opt_len);
target += opt_len;
left -= (opt_len + 1);
}
} while(opt_pos);
*target = '\0';
return NANOCOAP_URI_MAX - left;
}
ssize_t coap_handle_req(coap_pkt_t *pkt, uint8_t *resp_buf, unsigned resp_buf_len)
{
if (coap_get_code_class(pkt) != COAP_REQ) {
......@@ -154,13 +278,23 @@ ssize_t coap_handle_req(coap_pkt_t *pkt, uint8_t *resp_buf, unsigned resp_buf_le
unsigned method_flag = coap_method2flag(coap_get_code_detail(pkt));
#ifdef MODULE_GCOAP
uint8_t *uri = pkt->url;
#else
uint8_t uri[NANOCOAP_URI_MAX];
if (coap_get_uri(pkt, uri) <= 0) {
return -EBADMSG;
}
#endif
DEBUG("nanocoap: URI path: \"%s\"\n", uri);
for (unsigned i = 0; i < coap_resources_numof; i++) {
const coap_resource_t *resource = &coap_resources[i];
if (!(resource->methods & method_flag)) {
continue;
}
int res = strcmp((char *)pkt->url, resource->path);
int res = strcmp((char *)uri, resource->path);
if (res > 0) {
continue;
}
......@@ -282,17 +416,6 @@ static int _decode_value(unsigned val, uint8_t **pkt_pos_ptr, uint8_t *pkt_end)
return res;
}
static uint32_t _decode_uint(uint8_t *pkt_pos, unsigned nbytes)
{
assert(nbytes <= 4);
uint32_t res = 0;
if (nbytes) {
memcpy(((uint8_t *)&res) + (4 - nbytes), pkt_pos, nbytes);
}
return ntohl(res);
}
static unsigned _put_delta_optlen(uint8_t *buf, unsigned offset, unsigned shift, unsigned val)
{
if (val < 13) {
......@@ -408,3 +531,12 @@ ssize_t coap_well_known_core_default_handler(coap_pkt_t *pkt, uint8_t *buf, \
return coap_build_reply(pkt, COAP_CODE_205, buf, len, payload_len);
}
unsigned coap_get_len(coap_pkt_t *pkt)
{
unsigned pktlen = sizeof(coap_hdr_t) + coap_get_token_len(pkt);
if (pkt->payload) {
pktlen += pkt->payload_len + 1;
}
return pktlen;
}
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment