diff options
Diffstat (limited to 'aclk/aclk_rx_msgs.c')
| -rw-r--r-- | aclk/aclk_rx_msgs.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/aclk/aclk_rx_msgs.c b/aclk/aclk_rx_msgs.c new file mode 100644 index 000000000..fcb8d9968 --- /dev/null +++ b/aclk/aclk_rx_msgs.c @@ -0,0 +1,343 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include "aclk_rx_msgs.h" + +#include "aclk_stats.h" +#include "aclk_query_queue.h" + +#define ACLK_V2_PAYLOAD_SEPARATOR "\x0D\x0A\x0D\x0A" +#define ACLK_CLOUD_REQ_V2_PREFIX "GET /api/v1/" + +struct aclk_request { + char *type_id; + char *msg_id; + char *callback_topic; + char *payload; + int version; + int min_version; + int max_version; +}; + +int cloud_to_agent_parse(JSON_ENTRY *e) +{ + struct aclk_request *data = e->callback_data; + + switch (e->type) { + case JSON_OBJECT: + case JSON_ARRAY: + break; + case JSON_STRING: + if (!strcmp(e->name, "msg-id")) { + data->msg_id = strdupz(e->data.string); + break; + } + if (!strcmp(e->name, "type")) { + data->type_id = strdupz(e->data.string); + break; + } + if (!strcmp(e->name, "callback-topic")) { + data->callback_topic = strdupz(e->data.string); + break; + } + if (!strcmp(e->name, "payload")) { + if (likely(e->data.string)) { + size_t len = strlen(e->data.string); + data->payload = mallocz(len+1); + if (!url_decode_r(data->payload, e->data.string, len + 1)) + strcpy(data->payload, e->data.string); + } + break; + } + break; + case JSON_NUMBER: + if (!strcmp(e->name, "version")) { + data->version = e->data.number; + break; + } + if (!strcmp(e->name, "min-version")) { + data->min_version = e->data.number; + break; + } + if (!strcmp(e->name, "max-version")) { + data->max_version = e->data.number; + break; + } + + break; + + case JSON_BOOLEAN: + break; + + case JSON_NULL: + break; + } + return 0; +} + +static inline int aclk_extract_v2_data(char *payload, char **data) +{ + char* ptr = strstr(payload, ACLK_V2_PAYLOAD_SEPARATOR); + if(!ptr) + return 1; + ptr += strlen(ACLK_V2_PAYLOAD_SEPARATOR); + *data = strdupz(ptr); + return 0; +} + +static inline int aclk_v2_payload_get_query(const char *payload, char **query_url) +{ + const char *start, *end; + + if(strncmp(payload, ACLK_CLOUD_REQ_V2_PREFIX, strlen(ACLK_CLOUD_REQ_V2_PREFIX))) { + errno = 0; + error("Only accepting requests that start with \"%s\" from CLOUD.", ACLK_CLOUD_REQ_V2_PREFIX); + return 1; + } + start = payload + 4; + + if(!(end = strstr(payload, " HTTP/1.1\x0D\x0A"))) { + errno = 0; + error("Doesn't look like HTTP GET request."); + return 1; + } + + *query_url = mallocz((end - start) + 1); + strncpyz(*query_url, start, end - start); + + return 0; +} + +#define HTTP_CHECK_AGENT_INITIALIZED() ACLK_SHARED_STATE_LOCK;\ + if (unlikely(aclk_shared_state.agent_state == AGENT_INITIALIZING)) {\ + debug(D_ACLK, "Ignoring \"http\" cloud request; agent not in stable state");\ + ACLK_SHARED_STATE_UNLOCK;\ + return 1;\ + }\ + ACLK_SHARED_STATE_UNLOCK; + +static int aclk_handle_cloud_request_v2(struct aclk_request *cloud_to_agent, char *raw_payload) +{ + HTTP_CHECK_AGENT_INITIALIZED(); + + aclk_query_t query; + + errno = 0; + if (cloud_to_agent->version < ACLK_V_COMPRESSION) { + error( + "This handler cannot reply to request with version older than %d, received %d.", + ACLK_V_COMPRESSION, + cloud_to_agent->version); + return 1; + } + + query = aclk_query_new(HTTP_API_V2); + + if (unlikely(aclk_extract_v2_data(raw_payload, &query->data.http_api_v2.payload))) { + error("Error extracting payload expected after the JSON dictionary."); + goto error; + } + + if (unlikely(aclk_v2_payload_get_query(query->data.http_api_v2.payload, &query->dedup_id))) { + error("Could not extract payload from query"); + goto error; + } + + if (unlikely(!cloud_to_agent->callback_topic)) { + error("Missing callback_topic"); + goto error; + } + + if (unlikely(!cloud_to_agent->msg_id)) { + error("Missing msg_id"); + goto error; + } + + // aclk_queue_query takes ownership of data pointer + query->callback_topic = cloud_to_agent->callback_topic; + // for clarity and code readability as when we process the request + // it would be strange to get URL from `dedup_id` + query->data.http_api_v2.query = query->dedup_id; + query->msg_id = cloud_to_agent->msg_id; + aclk_queue_query(query); + return 0; + +error: + aclk_query_free(query); + return 1; +} + +// This handles `version` message from cloud used to negotiate +// protocol version we will use +static int aclk_handle_version_response(struct aclk_request *cloud_to_agent, char *raw_payload) +{ + UNUSED(raw_payload); + int version = -1; + errno = 0; + + if (unlikely(cloud_to_agent->version != ACLK_VERSION_NEG_VERSION)) { + error( + "Unsuported version of \"version\" message from cloud. Expected %d, Got %d", + ACLK_VERSION_NEG_VERSION, + cloud_to_agent->version); + return 1; + } + if (unlikely(!cloud_to_agent->min_version)) { + error("Min version missing or 0"); + return 1; + } + if (unlikely(!cloud_to_agent->max_version)) { + error("Max version missing or 0"); + return 1; + } + if (unlikely(cloud_to_agent->max_version < cloud_to_agent->min_version)) { + error( + "Max version (%d) must be >= than min version (%d)", cloud_to_agent->max_version, + cloud_to_agent->min_version); + return 1; + } + + if (unlikely(cloud_to_agent->min_version > ACLK_VERSION_MAX)) { + error( + "Agent too old for this cloud. Minimum version required by cloud %d." + " Maximum version supported by this agent %d.", + cloud_to_agent->min_version, ACLK_VERSION_MAX); + aclk_kill_link = 1; + aclk_disable_runtime = 1; + return 1; + } + if (unlikely(cloud_to_agent->max_version < ACLK_VERSION_MIN)) { + error( + "Cloud version is too old for this agent. Maximum version supported by cloud %d." + " Minimum (oldest) version supported by this agent %d.", + cloud_to_agent->max_version, ACLK_VERSION_MIN); + aclk_kill_link = 1; + return 1; + } + + version = MIN(cloud_to_agent->max_version, ACLK_VERSION_MAX); + + ACLK_SHARED_STATE_LOCK; + if (unlikely(now_monotonic_usec() > aclk_shared_state.version_neg_wait_till)) { + errno = 0; + error("The \"version\" message came too late ignoring."); + goto err_cleanup; + } + if (unlikely(aclk_shared_state.version_neg)) { + errno = 0; + error("Version has already been set to %d", aclk_shared_state.version_neg); + goto err_cleanup; + } + aclk_shared_state.version_neg = version; + ACLK_SHARED_STATE_UNLOCK; + + info("Choosing version %d of ACLK", version); + + aclk_set_rx_handlers(version); + + return 0; + +err_cleanup: + ACLK_SHARED_STATE_UNLOCK; + return 1; +} + +typedef struct aclk_incoming_msg_type{ + char *name; + int(*fnc)(struct aclk_request *, char *); +}aclk_incoming_msg_type; + +aclk_incoming_msg_type aclk_incoming_msg_types_compression[] = { + { .name = "http", .fnc = aclk_handle_cloud_request_v2 }, + { .name = "version", .fnc = aclk_handle_version_response }, + { .name = NULL, .fnc = NULL } +}; + +struct aclk_incoming_msg_type *aclk_incoming_msg_types = aclk_incoming_msg_types_compression; + +void aclk_set_rx_handlers(int version) +{ +// ACLK_NG ACLK version support starts at 2 +// TODO ACLK v3 + UNUSED(version); + aclk_incoming_msg_types = aclk_incoming_msg_types_compression; +} + +int aclk_handle_cloud_message(char *payload) +{ + struct aclk_request cloud_to_agent; + memset(&cloud_to_agent, 0, sizeof(struct aclk_request)); + + if (aclk_stats_enabled) { + ACLK_STATS_LOCK; + aclk_metrics_per_sample.cloud_req_recvd++; + ACLK_STATS_UNLOCK; + } + + if (unlikely(!payload)) { + errno = 0; + error("ACLK incoming message is empty"); + goto err_cleanup_nojson; + } + + debug(D_ACLK, "ACLK incoming message (%s)", payload); + + int rc = json_parse(payload, &cloud_to_agent, cloud_to_agent_parse); + + if (unlikely(rc != JSON_OK)) { + errno = 0; + error("Malformed json request (%s)", payload); + goto err_cleanup; + } + + if (!cloud_to_agent.type_id) { + errno = 0; + error("Cloud message is missing compulsory key \"type\""); + goto err_cleanup; + } + + if (!aclk_shared_state.version_neg && strcmp(cloud_to_agent.type_id, "version")) { + error("Only \"version\" message is allowed before popcorning and version negotiation is finished. Ignoring"); + goto err_cleanup; + } + + for (int i = 0; aclk_incoming_msg_types[i].name; i++) { + if (strcmp(cloud_to_agent.type_id, aclk_incoming_msg_types[i].name) == 0) { + if (likely(!aclk_incoming_msg_types[i].fnc(&cloud_to_agent, payload))) { + // in case of success handler is supposed to clean up after itself + // or as in the case of aclk_handle_cloud_request take + // ownership of the pointers (done to avoid copying) + // see what `aclk_queue_query` parameter `internal` does + + // NEVER CONTINUE THIS LOOP AFTER CALLING FUNCTION!!! + // msg handlers (namely aclk_handle_version_responce) + // can freely change what aclk_incoming_msg_types points to + // so either exit or restart this for loop + freez(cloud_to_agent.type_id); + return 0; + } + goto err_cleanup; + } + } + + errno = 0; + error("Unknown message type from Cloud \"%s\"", cloud_to_agent.type_id); + +err_cleanup: + if (cloud_to_agent.payload) + freez(cloud_to_agent.payload); + if (cloud_to_agent.type_id) + freez(cloud_to_agent.type_id); + if (cloud_to_agent.msg_id) + freez(cloud_to_agent.msg_id); + if (cloud_to_agent.callback_topic) + freez(cloud_to_agent.callback_topic); + +err_cleanup_nojson: + if (aclk_stats_enabled) { + ACLK_STATS_LOCK; + aclk_metrics_per_sample.cloud_req_err++; + ACLK_STATS_UNLOCK; + } + + return 1; +} |