coap.h

00001 #ifndef COAP_H
00002 #define COAP_H 1
00003 
00004 #ifdef __cplusplus
00005 extern "C" {
00006 #endif
00007 
00008 #include <stdint.h>
00009 #include <stdbool.h>
00010 #include <stddef.h>
00011 
00012 #define MAXOPT 16
00013 
00014 //http://tools.ietf.org/html/rfc7252#section-3
00015 typedef struct
00016 {
00017     uint8_t ver;                /* CoAP version number */
00018     uint8_t t;                  /* CoAP Message Type */
00019     uint8_t tkl;                /* Token length: indicates length of the Token field */
00020     uint8_t code;               /* CoAP status code. Can be request (0.xx), success reponse (2.xx), 
00021                                  * client error response (4.xx), or rever error response (5.xx) 
00022                                  * For possible values, see http://tools.ietf.org/html/rfc7252#section-12.1 */
00023     uint8_t id[2];
00024 } coap_header_t;
00025 
00026 typedef struct
00027 {
00028     const uint8_t *p;
00029     size_t len;
00030 } coap_buffer_t;
00031 
00032 typedef struct
00033 {
00034     uint8_t *p;
00035     size_t len;
00036 } coap_rw_buffer_t;
00037 
00038 typedef struct
00039 {
00040     uint8_t num;                /* Option number. See http://tools.ietf.org/html/rfc7252#section-5.10 */
00041     coap_buffer_t buf;          /* Option value */
00042 } coap_option_t;
00043 
00044 typedef struct
00045 {
00046     coap_header_t hdr;          /* Header of the packet */
00047     coap_buffer_t tok;          /* Token value, size as specified by hdr.tkl */
00048     uint8_t numopts;            /* Number of options */
00049     coap_option_t opts[MAXOPT]; /* Options of the packet. For possible entries see
00050                                  * http://tools.ietf.org/html/rfc7252#section-5.10 */
00051     coap_buffer_t payload;      /* Payload carried by the packet */
00052 } coap_packet_t;
00053 
00054 /////////////////////////////////////////
00055 
00056 //http://tools.ietf.org/html/rfc7252#section-12.2
00057 typedef enum
00058 {
00059     COAP_OPTION_IF_MATCH = 1,
00060     COAP_OPTION_URI_HOST = 3,
00061     COAP_OPTION_ETAG = 4,
00062     COAP_OPTION_IF_NONE_MATCH = 5,
00063     COAP_OPTION_OBSERVE = 6,
00064     COAP_OPTION_URI_PORT = 7,
00065     COAP_OPTION_LOCATION_PATH = 8,
00066     COAP_OPTION_URI_PATH = 11,
00067     COAP_OPTION_CONTENT_FORMAT = 12,
00068     COAP_OPTION_MAX_AGE = 14,
00069     COAP_OPTION_URI_QUERY = 15,
00070     COAP_OPTION_ACCEPT = 17,
00071     COAP_OPTION_LOCATION_QUERY = 20,
00072     COAP_OPTION_PROXY_URI = 35,
00073     COAP_OPTION_PROXY_SCHEME = 39
00074 } coap_option_num_t;
00075 
00076 //http://tools.ietf.org/html/rfc7252#section-12.1.1
00077 typedef enum
00078 {
00079     COAP_METHOD_GET = 1,
00080     COAP_METHOD_POST = 2,
00081     COAP_METHOD_PUT = 3,
00082     COAP_METHOD_DELETE = 4
00083 } coap_method_t;
00084 
00085 //http://tools.ietf.org/html/rfc7252#section-12.1.1
00086 typedef enum
00087 {
00088     COAP_TYPE_CON = 0,
00089     COAP_TYPE_NONCON = 1,
00090     COAP_TYPE_ACK = 2,
00091     COAP_TYPE_RESET = 3
00092 } coap_msgtype_t;
00093 
00094 //http://tools.ietf.org/html/rfc7252#section-5.2
00095 //http://tools.ietf.org/html/rfc7252#section-12.1.2
00096 #define MAKE_RSPCODE(clas, det) ((clas << 5) | (det))
00097 typedef enum
00098 {
00099     COAP_RSPCODE_CONTENT = MAKE_RSPCODE(2, 5),
00100     COAP_RSPCODE_NOT_FOUND = MAKE_RSPCODE(4, 4),
00101     COAP_RSPCODE_BAD_REQUEST = MAKE_RSPCODE(4, 0),
00102     COAP_RSPCODE_CHANGED = MAKE_RSPCODE(2, 4)
00103 } coap_responsecode_t;
00104 
00105 //http://tools.ietf.org/html/rfc7252#section-12.3
00106 typedef enum
00107 {
00108     COAP_CONTENTTYPE_NONE = -1, // bodge to allow us not to send option block
00109     COAP_CONTENTTYPE_TEXT_PLAIN = 0,
00110     COAP_CONTENTTYPE_APPLICATION_LINKFORMAT = 40,
00111     COAP_CONTENTTYPE_APPLICATION_XML = 41,
00112     COAP_CONTENTTYPE_APPLICATION_OCTECT_STREAM = 42,
00113     COAP_CONTENTTYPE_APPLICATION_EXI = 47,
00114     COAP_CONTENTTYPE_APPLICATION_JSON = 50,
00115 } coap_content_type_t;
00116 
00117 ///////////////////////
00118 
00119 typedef enum
00120 {
00121     COAP_ERR_NONE = 0,
00122     COAP_ERR_HEADER_TOO_SHORT = 1,
00123     COAP_ERR_VERSION_NOT_1 = 2,
00124     COAP_ERR_TOKEN_TOO_SHORT = 3,
00125     COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER = 4,
00126     COAP_ERR_OPTION_TOO_SHORT = 5,
00127     COAP_ERR_OPTION_OVERRUNS_PACKET = 6,
00128     COAP_ERR_OPTION_TOO_BIG = 7,
00129     COAP_ERR_OPTION_LEN_INVALID = 8,
00130     COAP_ERR_BUFFER_TOO_SMALL = 9,
00131     COAP_ERR_UNSUPPORTED = 10,
00132     COAP_ERR_OPTION_DELTA_INVALID = 11,
00133 } coap_error_t;
00134 
00135 ///////////////////////
00136 
00137 typedef int (*coap_endpoint_func)(coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo);
00138 #define MAX_SEGMENTS 2  // 2 = /foo/bar, 3 = /foo/bar/baz
00139 typedef struct
00140 {
00141     int count;
00142     const char *elems[MAX_SEGMENTS];
00143 } coap_endpoint_path_t;
00144 
00145 typedef struct
00146 {
00147     coap_method_t method;               /* (i.e. POST, PUT or GET) */
00148     coap_endpoint_func handler;         /* callback function which handles this 
00149                                          * type of endpoint (and calls 
00150                                          * coap_make_response() at some point) */
00151     const coap_endpoint_path_t *path;   /* path towards a resource (i.e. foo/bar/) */ 
00152     const char *core_attr;              /* the 'ct' attribute, as defined in RFC7252, section 7.2.1.:
00153                                          * "The Content-Format code "ct" attribute 
00154                                          * provides a hint about the 
00155                                          * Content-Formats this resource returns." 
00156                                          * (Section 12.3. lists possible ct values.) */
00157 } coap_endpoint_t;
00158 
00159 
00160 ///////////////////////
00161 void coap_dumpPacket(coap_packet_t *pkt);
00162 int coap_parse(coap_packet_t *pkt, const uint8_t *buf, size_t buflen);
00163 int coap_buffer_to_string(char *strbuf, size_t strbuflen, const coap_buffer_t *buf);
00164 const coap_option_t *coap_findOptions(const coap_packet_t *pkt, uint8_t num, uint8_t *count);
00165 int coap_build(uint8_t *buf, size_t *buflen, const coap_packet_t *pkt);
00166 void coap_dump(const uint8_t *buf, size_t buflen, bool bare);
00167 int coap_make_response(coap_rw_buffer_t *scratch, coap_packet_t *pkt, const uint8_t *content, size_t content_len, uint8_t msgid_hi, uint8_t msgid_lo, const coap_buffer_t* tok, coap_responsecode_t rspcode, coap_content_type_t content_type);
00168 int coap_handle_req(coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt);
00169 void coap_option_nibble(uint32_t value, uint8_t *nibble);
00170 void coap_setup(void);
00171 void endpoint_setup(void);
00172 
00173 #ifdef __cplusplus
00174 }
00175 #endif
00176 
00177 #endif
00178 
00179 extern const coap_endpoint_t endpoints[];