| /* |
| * Copyright (c) 2013, Institute for Pervasive Computing, ETH Zurich |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of the Institute nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * This file is part of the Contiki operating system. |
| */ |
| |
| /** |
| * \file |
| * CoAP module for observing resources (draft-ietf-core-observe-11). |
| * \author |
| * Matthias Kovatsch <kovatsch@inf.ethz.ch> |
| */ |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include "er-coap-observe.h" |
| |
| #ifdef CONFIG_NETWORK_IP_STACK_DEBUG_COAP_OBSERVE |
| #define DEBUG 1 |
| #endif |
| #include "contiki/ip/uip-debug.h" |
| |
| /*---------------------------------------------------------------------------*/ |
| MEMB(observers_memb, coap_observer_t, COAP_MAX_OBSERVERS); |
| LIST(observers_list); |
| /*---------------------------------------------------------------------------*/ |
| /*- Internal API ------------------------------------------------------------*/ |
| /*---------------------------------------------------------------------------*/ |
| static coap_observer_t * |
| coap_add_observer(coap_context_t *coap_ctx, uip_ipaddr_t *addr, uint16_t port, |
| const uint8_t *token, size_t token_len, |
| const char *uri, int uri_len) |
| { |
| /* Remove existing observe relationship, if any. */ |
| coap_remove_observer_by_uri(addr, port, uri); |
| |
| coap_observer_t *o = memb_alloc(&observers_memb); |
| |
| if(o) { |
| /* o->url = uri; */ |
| int max = sizeof(o->url); |
| if(max > uri_len) { |
| max = uri_len; |
| } |
| memcpy(o->url, uri, max); |
| o->url[max] = 0; |
| uip_ipaddr_copy(&o->addr, addr); |
| o->port = port; |
| o->coap_ctx = coap_ctx; |
| o->token_len = token_len; |
| memcpy(o->token, token, token_len); |
| o->last_mid = 0; |
| |
| PRINTF("Adding observer (%u/%u) for /%s [0x%02X%02X]\n", |
| list_length(observers_list) + 1, COAP_MAX_OBSERVERS, |
| o->url, o->token[0], o->token[1]); |
| list_add(observers_list, o); |
| } |
| |
| return o; |
| } |
| /*---------------------------------------------------------------------------*/ |
| /*- Removal -----------------------------------------------------------------*/ |
| /*---------------------------------------------------------------------------*/ |
| void |
| coap_remove_observer(coap_observer_t *o) |
| { |
| PRINTF("Removing observer for /%s [0x%02X%02X]\n", o->url, o->token[0], |
| o->token[1]); |
| |
| memb_free(&observers_memb, o); |
| list_remove(observers_list, o); |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| coap_remove_observer_by_client(uip_ipaddr_t *addr, uint16_t port) |
| { |
| int removed = 0; |
| coap_observer_t *obs = NULL; |
| |
| for(obs = (coap_observer_t *)list_head(observers_list); obs; |
| obs = obs->next) { |
| PRINTF("Remove check client "); |
| PRINT6ADDR(addr); |
| PRINTF(":%u\n", port); |
| if(uip_ipaddr_cmp(&obs->addr, addr) && obs->port == port) { |
| coap_remove_observer(obs); |
| removed++; |
| } |
| } |
| return removed; |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| coap_remove_observer_by_token(uip_ipaddr_t *addr, uint16_t port, |
| uint8_t *token, size_t token_len) |
| { |
| int removed = 0; |
| coap_observer_t *obs = NULL; |
| |
| for(obs = (coap_observer_t *)list_head(observers_list); obs; |
| obs = obs->next) { |
| PRINTF("Remove check Token 0x%02X%02X\n", token[0], token[1]); |
| if(uip_ipaddr_cmp(&obs->addr, addr) && obs->port == port |
| && obs->token_len == token_len |
| && memcmp(obs->token, token, token_len) == 0) { |
| coap_remove_observer(obs); |
| removed++; |
| } |
| } |
| return removed; |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| coap_remove_observer_by_uri(const uip_ipaddr_t *addr, uint16_t port, |
| const char *uri) |
| { |
| int removed = 0; |
| coap_observer_t *obs = NULL; |
| |
| for(obs = (coap_observer_t *)list_head(observers_list); obs; |
| obs = obs->next) { |
| PRINTF("Remove check URL %p\n", uri); |
| if((addr == NULL |
| || (uip_ipaddr_cmp(&obs->addr, addr) && obs->port == port)) |
| && (obs->url == uri || memcmp(obs->url, uri, strlen(obs->url)) == 0)) { |
| coap_remove_observer(obs); |
| removed++; |
| } |
| } |
| return removed; |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| coap_remove_observer_by_mid(coap_context_t *coap_ctx, |
| uip_ipaddr_t *addr, uint16_t port, uint16_t mid) |
| { |
| int removed = 0; |
| coap_observer_t *obs = NULL; |
| |
| for(obs = (coap_observer_t *)list_head(observers_list); obs; |
| obs = obs->next) { |
| PRINTF("Remove check MID %u\n", mid); |
| if(uip_ipaddr_cmp(&obs->addr, addr) && obs->port == port |
| && obs->coap_ctx == coap_ctx |
| && obs->last_mid == mid) { |
| coap_remove_observer(obs); |
| removed++; |
| } |
| } |
| return removed; |
| } |
| /*---------------------------------------------------------------------------*/ |
| /*- Notification ------------------------------------------------------------*/ |
| /*---------------------------------------------------------------------------*/ |
| void |
| coap_notify_observers(resource_t *resource) |
| { |
| coap_notify_observers_sub(resource, NULL); |
| } |
| void |
| coap_notify_observers_sub(resource_t *resource, char *subpath) |
| { |
| /* build notification */ |
| coap_packet_t notification[1]; /* this way the packet can be treated as pointer as usual */ |
| coap_packet_t request[1]; /* this way the packet can be treated as pointer as usual */ |
| coap_observer_t *obs = NULL; |
| int url_len = 0; |
| char url[COAP_OBSERVER_URL_LEN]; |
| |
| url_len = strlen(resource->url); |
| strncpy(url, resource->url, COAP_OBSERVER_URL_LEN - 1); |
| if(strlen(url) < COAP_OBSERVER_URL_LEN && subpath != NULL) { |
| strncpy(&url[url_len], subpath, COAP_OBSERVER_URL_LEN - url_len - 1); |
| } |
| /* Ensure url is null terminated because strncpy does not guarantee this */ |
| url[COAP_OBSERVER_URL_LEN - 1] = '\0'; |
| /* url now contains the notify URL that needs to match the observer */ |
| PRINTF("Observe: Notification from %s\n", url); |
| |
| coap_init_message(notification, COAP_TYPE_NON, CONTENT_2_05, 0); |
| /* create a "fake" request for the URI */ |
| coap_init_message(request, COAP_TYPE_CON, COAP_GET, 0); |
| coap_set_header_uri_path(request, url); |
| |
| /* iterate over observers */ |
| for(obs = (coap_observer_t *)list_head(observers_list); obs; |
| obs = obs->next) { |
| url_len = strlen(obs->url); |
| |
| /* Do a match based on the parent/sub-resource match so that it is |
| possible to do parent-node observe */ |
| if((url_len == strlen(url) |
| || (url_len > strlen(url) |
| && (resource->flags & HAS_SUB_RESOURCES) |
| && obs->url[strlen(url)] == '/')) |
| && strncmp(url, obs->url, strlen(url)) == 0) { |
| coap_transaction_t *transaction = NULL; |
| |
| obs->coap_ctx->buf = ip_buf_get_tx(obs->coap_ctx->net_ctx); |
| if(!obs->coap_ctx->buf) { |
| PRINTF("Failed to get buffer, discard observe message\n"); |
| return; |
| } |
| uip_set_udp_conn(obs->coap_ctx->buf) = NULL; |
| uip_ipaddr_copy(&net_context_get_udp_connection(obs->coap_ctx->net_ctx)->remote_addr, &obs->addr); |
| net_context_get_udp_connection(obs->coap_ctx->net_ctx)->remote_port = uip_ntohs(obs->port); |
| |
| if((transaction = coap_new_transaction(coap_get_mid(), obs->coap_ctx, |
| &obs->addr, obs->port))) { |
| if(obs->obs_counter % COAP_OBSERVE_REFRESH_INTERVAL == 0) { |
| PRINTF(" Force Confirmable for\n"); |
| notification->type = COAP_TYPE_CON; |
| } |
| |
| PRINTF(" Observer "); |
| PRINT6ADDR(&obs->addr); |
| PRINTF(":%u\n", obs->port); |
| |
| /* update last MID for RST matching */ |
| obs->last_mid = transaction->mid; |
| |
| /* prepare response */ |
| notification->mid = transaction->mid; |
| |
| resource->get_handler(request, notification, |
| transaction->packet + COAP_MAX_HEADER_SIZE, |
| REST_MAX_CHUNK_SIZE, NULL); |
| |
| if(notification->code < BAD_REQUEST_4_00) { |
| coap_set_header_observe(notification, (obs->obs_counter)++); |
| } |
| coap_set_token(notification, obs->token, obs->token_len); |
| |
| transaction->packet_len = |
| coap_serialize_message(notification, uip_appdata(obs->coap_ctx->buf)); |
| |
| coap_send_transaction(transaction); |
| } |
| } |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| coap_observe_handler(resource_t *resource, void *request, void *response) |
| { |
| coap_packet_t *const coap_req = (coap_packet_t *)request; |
| coap_packet_t *const coap_res = (coap_packet_t *)response; |
| coap_context_t *coap_ctx = coap_get_context(request); |
| coap_observer_t * obs; |
| |
| /* static char content[16]; */ |
| |
| if(coap_req->code == COAP_GET && coap_res->code < 128) { /* GET request and response without error code */ |
| if(IS_OPTION(coap_req, COAP_OPTION_OBSERVE)) { |
| if(coap_req->observe == 0) { |
| obs = coap_add_observer(coap_ctx, |
| &UIP_IP_BUF(coap_ctx->buf)->srcipaddr, |
| UIP_UDP_BUF(coap_ctx->buf)->srcport, |
| coap_req->token, coap_req->token_len, |
| coap_req->uri_path, coap_req->uri_path_len); |
| if(obs) { |
| coap_set_header_observe(coap_res, (obs->obs_counter)++); |
| /* |
| * Following payload is for demonstration purposes only. |
| * A subscription should return the same representation as a normal GET. |
| * Uncomment if you want an information about the avaiable observers. |
| */ |
| /* |
| * coap_set_payload(coap_res, |
| * content, |
| * snprintf(content, sizeof(content), "Added %u/%u", |
| * list_length(observers_list), |
| * COAP_MAX_OBSERVERS)); |
| */ |
| } else { |
| coap_res->code = SERVICE_UNAVAILABLE_5_03; |
| coap_set_payload(coap_res, "TooManyObservers", 16); |
| } |
| } else if(coap_req->observe == 1) { |
| |
| /* remove client if it is currently observe */ |
| coap_remove_observer_by_token(&UIP_IP_BUF(coap_ctx->buf)->srcipaddr, |
| UIP_UDP_BUF(coap_ctx->buf)->srcport, coap_req->token, |
| coap_req->token_len); |
| } |
| } |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |