/**
* @file fastcgi.c
- * @purpose Runs the FCGI request loop to handle web interface requests.
+ * @brief Runs the FCGI request loop to handle web interface requests.
*
* fcgi_stdio.h must be included before all else so the stdio function
* redirection works ok.
#include <fcgi_stdio.h>
#include <openssl/sha.h>
-#include "fastcgi.h"
+
#include "common.h"
#include "sensor.h"
-#include "log.h"
-#include <time.h>
+#include "control.h"
+#include "options.h"
+
+/**The time period (in seconds) before the control key expires @ */
+#define CONTROL_TIMEOUT 180
+
+/**Contextual information related to FCGI requests*/
+struct FCGIContext {
+ /**The time of last valid user access possessing the control key*/
+ time_t control_timestamp;
+ char control_key[41];
+ char control_ip[16];
+ /**The name of the current module**/
+ const char *current_module;
+ /**For debugging purposes?**/
+ int response_number;
+};
-static void LoginHandler(void *data, char *params) {
- static char loginkey[41] = {0}, ip[256];
- static time_t timestamp = 0;
+/**
+ * Identifies build information and the current API version to the user.
+ * Also useful for testing that the API is running and identifying the
+ * sensors and actuators present.
+ * @param context The context to work in
+ * @param params User specified paramters: [actuators, sensors]
+ */
+static void IdentifyHandler(FCGIContext *context, char *params) {
+ bool identSensors = false, identActuators = false;
const char *key, *value;
- int force = 0, end = 0;
+ int i;
while ((params = FCGI_KeyPair(params, &key, &value))) {
- if (!strcmp(key, "force"))
- force = !force;
- else if (!strcmp(key, "end"))
- end = !end;
+ if (!strcmp(key, "sensors")) {
+ identSensors = !identSensors;
+ } else if (!strcmp(key, "actuators")) {
+ identActuators = !identActuators;
+ }
}
- if (end) {
- *loginkey = 0;
- FCGI_BeginJSON(200, "login");
- FCGI_EndJSON();
- return;
+ FCGI_BeginJSON(context, STATUS_OK);
+ FCGI_JSONPair("description", "MCTX3420 Server API (2013)");
+ FCGI_JSONPair("build_date", __DATE__ " " __TIME__);
+ FCGI_JSONLong("api_version", API_VERSION);
+ if (identSensors) {
+ FCGI_JSONKey("sensors");
+ FCGI_JSONValue("{\n\t\t");
+ for (i = 0; i < NUMSENSORS; i++) {
+ if (i > 0) {
+ FCGI_JSONValue(",\n\t\t");
+ }
+ FCGI_JSONValue("\"%d\" : \"%s\"", i, g_sensor_names[i]);
+ }
+ FCGI_JSONValue("\n\t}");
+ }
+ if (identActuators) {
+ FCGI_JSONKey("actuators");
+ FCGI_JSONValue("{\n\t\t");
+ for (i = 0; i < NUMACTUATORS; i++) {
+ if (i > 0) {
+ FCGI_JSONValue(",\n\t\t");
+ }
+ FCGI_JSONValue("\"%d\" : \"%s\"", i, g_actuator_names[i]);
+ }
+ FCGI_JSONValue("\n\t}");
}
+ FCGI_EndJSON();
+}
+/**
+ * Gives the user a key that determines who has control over
+ * the system at any one time. The key can be forcibly generated, revoking
+ * any previous control keys. To be used in conjunction with HTTP
+ * basic authentication.
+ * This function will generate a JSON response that indicates success/failure.
+ * @param context The context to work in
+ * @param force Whether to force key generation or not.
+ */
+void FCGI_BeginControl(FCGIContext *context, bool force) {
time_t now = time(NULL);
- if (force || !*loginkey || (now - timestamp > 180)) {
+ bool expired = now - context->control_timestamp > CONTROL_TIMEOUT;
+
+ if (force || !*(context->control_key) || expired) {
SHA_CTX sha1ctx;
unsigned char sha1[20];
int i = rand();
SHA1_Update(&sha1ctx, &i, sizeof(i));
SHA1_Final(sha1, &sha1ctx);
- timestamp = now;
+ context->control_timestamp = now;
for (i = 0; i < 20; i++)
- sprintf(loginkey+i*2, "%02x", sha1[i]);
- sprintf(ip, "%s", getenv("REMOTE_ADDR"));
- FCGI_BeginJSON(200, "login");
- FCGI_BuildJSON("key", loginkey);
- FCGI_EndJSON();
+ sprintf(context->control_key + i * 2, "%02x", sha1[i]);
+ snprintf(context->control_ip, 16, "%s", getenv("REMOTE_ADDR"));
+ FCGI_BeginJSON(context, STATUS_OK);
+ FCGI_JSONPair("key", context->control_key);
+ FCGI_EndJSON();
} else {
char buf[128];
- strftime(buf, 128, "%H:%M:%S %d-%m-%Y",localtime(×tamp));
- FCGI_BeginJSON(401, "login");
- FCGI_BuildJSON("description", "Already logged in");
- FCGI_BuildJSON("user", ip);
- FCGI_BuildJSON("time", buf);
+ strftime(buf, 128, "%H:%M:%S %d-%m-%Y",
+ localtime(&(context->control_timestamp)));
+ FCGI_BeginJSON(context, STATUS_UNAUTHORIZED);
+ FCGI_JSONPair("description", "Another user already has control");
+ FCGI_JSONPair("current_user", context->control_ip);
+ FCGI_JSONPair("when", buf);
FCGI_EndJSON();
}
}
/**
- * Handle a request to the sensor module
- * @param data - Data to pass to module (?)
- * @param params - Parameters passed
+ * Given an FCGIContext, determines if the current user (as specified by
+ * the key) has control or not. If validated, the context control_timestamp is
+ * updated.
+ * @param context The context to work in
+ * @param key The control key to be validated.
+ * @return TRUE if authorized, FALSE if not.
*/
-static void SensorHandler(void * data, char * params)
-{
- static DataPoint buffer[SENSOR_QUERYBUFSIZ];
- StatusCodes status = STATUS_OK;
- const char * key; const char * value;
-
- int sensor_id = SENSOR_NONE;
-
- do
- {
- params = FCGI_KeyPair(params, &key, &value);
- Log(LOGDEBUG, "Got key=%s and value=%s", key, value);
- if (strcmp(key, "id") == 0)
- {
- if (sensor_id != SENSOR_NONE)
- {
- Log(LOGERR, "Only one sensor id should be specified");
- status = STATUS_BADREQUEST;
- break;
- }
- //TODO: Use human readable sensor identifier string for API?
- sensor_id = atoi(value);
- if (sensor_id == 0 && strcmp(value, "0") != 0)
- {
- Log(LOGERR, "Sensor id not an integer; %s", value);
- status = STATUS_BADREQUEST;
- break;
- }
- }
- else
- {
- Log(LOGERR, "Unknown key \"%s\" (value = %s)", key, value);
- status = STATUS_BADREQUEST;
- break;
- }
- }
- while (params != NULL && *params != '\0');
-
- if (sensor_id == SENSOR_NONE)
- {
- Log(LOGERR, "No sensor id specified");
- status = STATUS_BADREQUEST;
- }
- if (sensor_id >= NUMSENSORS || sensor_id < 0)
- {
- Log(LOGERR, "Invalid sensor id %d", sensor_id);
- status = STATUS_BADREQUEST;
+bool FCGI_HasControl(FCGIContext *context, const char *key) {
+ time_t now = time(NULL);
+ int result = (now - context->control_timestamp) <= CONTROL_TIMEOUT &&
+ key != NULL && !strcmp(context->control_key, key);
+ if (result) {
+ context->control_timestamp = now; //Update the control_timestamp
}
+ return result;
+}
- FCGI_BeginJSON(status, "sensor");
-
- if (status != STATUS_BADREQUEST)
- {
- FCGI_BuildJSON(key, value); // should spit back sensor ID
- //Log(LOGDEBUG, "Call Sensor_Query...");
- int amount_read = Sensor_Query(&(g_sensors[sensor_id]), buffer, SENSOR_QUERYBUFSIZ);
- //Log(LOGDEBUG, "Read %d DataPoints", amount_read);
- //Log(LOGDEBUG, "Produce JSON response");
- printf(",\r\n\t\"data\" : [");
- for (int i = 0; i < amount_read; ++i)
- {
- printf("[%f,%f]", buffer[i].time, buffer[i].value);
- if (i+1 < amount_read)
- printf(",");
- }
- printf("]");
- //Log(LOGDEBUG, "Done producing JSON response");
- }
- FCGI_EndJSON();
-
+
+/**
+ * Revokes the current control key, if present.
+ * @param context The context to work in
+ */
+void FCGI_EndControl(FCGIContext *context) {
+ *(context->control_key) = 0;
+ FCGI_BeginJSON(context, STATUS_OK);
+ FCGI_EndJSON();
+ return;
}
/**
/**
* Begins a response to the client in JSON format.
- * @param status_code The HTTP status code to be returned.
- * @param module The name of the module that initiated the response.
+ * @param context The context to work in.
+ * @param status_code The status code to be returned.
*/
-void FCGI_BeginJSON(StatusCodes status_code, const char *module)
+void FCGI_BeginJSON(FCGIContext *context, StatusCodes status_code)
{
- switch (status_code) {
- case STATUS_OK:
- break;
- case STATUS_UNAUTHORIZED:
- printf("Status: 401 Unauthorized\r\n");
- break;
- default:
- printf("Status: 400 Bad Request\r\n");
- }
printf("Content-type: application/json; charset=utf-8\r\n\r\n");
printf("{\r\n");
- printf("\t\"module\" : \"%s\"", module);
+ printf("\t\"module\" : \"%s\"", context->current_module);
+ FCGI_JSONLong("status", status_code);
+
+ // Jeremy: Should we include a timestamp in the JSON; something like this?
+ double start_time = g_options.start_time.tv_sec + 1e-6*(g_options.start_time.tv_usec);
+ struct timeval now;
+ gettimeofday(&now, NULL);
+ double current_time = now.tv_sec + 1e-6*(now.tv_usec);
+ FCGI_JSONDouble("start_time", start_time);
+ FCGI_JSONDouble("current_time", current_time);
+ FCGI_JSONDouble("running_time", current_time - start_time);
}
/**
* Adds a key/value pair to a JSON response. The response must have already
* been initiated by FCGI_BeginJSON. Note that characters are not escaped.
* @param key The key of the JSON entry
- * ¶m value The value associated with the key.
+ * @param value The value associated with the key.
*/
-void FCGI_BuildJSON(const char *key, const char *value)
+void FCGI_JSONPair(const char *key, const char *value)
{
printf(",\r\n\t\"%s\" : \"%s\"", key, value);
}
+/**
+ * Similar to FCGI_JSONPair except for signed integer values.
+ * @param key The key of the JSON entry
+ * @param value The value associated with the key
+ */
+void FCGI_JSONLong(const char *key, long value)
+{
+ printf(",\r\n\t\"%s\" : %ld", key, value);
+}
+
+/**
+ * Similar to FCGI_JsonPair except for floating point values.
+ * @param key The key of the JSON entry
+ * @param value The value associated with the key
+ */
+void FCGI_JSONDouble(const char *key, double value)
+{
+ printf(",\r\n\t\"%s\" : %f", key, value);
+}
+
+/**
+ * Similar to FCGI_JsonPair except for boolean values.
+ * @param key The key of the JSON entry
+ * @param value The value associated with the key
+ */
+void FCGI_JSONBool(const char *key, bool value)
+{
+ printf(",\r\n\t\"%s\" : %s", key, value ? "true" : "false");
+}
+
+/**
+ * Begins a JSON entry by writing the key. To be used in conjunction
+ * with FCGI_JsonValue.
+ * @param key The key of the JSON entry
+ */
+void FCGI_JSONKey(const char *key)
+{
+ printf(",\r\n\t\"%s\" : ", key);
+}
+
/**
* Ends a JSON response that was initiated by FCGI_BeginJSON.
*/
printf("\r\n}\r\n");
}
+/**
+ * To be used when the input parameters are rejected. The return data
+ * will also have debugging information provided.
+ * @param context The context to work in
+ * @param status The status the return data should have.
+ * @param description A short description of why the input was rejected.
+ */
+void FCGI_RejectJSONEx(FCGIContext *context, StatusCodes status, const char *description)
+{
+ if (description == NULL)
+ description = "Unknown";
+
+ Log(LOGINFO, "%s: Rejected query with: %d: %s", context->current_module, status, description);
+ FCGI_BeginJSON(context, status);
+ FCGI_JSONPair("description", description);
+ FCGI_JSONLong("responsenumber", context->response_number);
+ FCGI_JSONPair("params", getenv("QUERY_STRING"));
+ FCGI_JSONPair("host", getenv("SERVER_HOSTNAME"));
+ FCGI_JSONPair("user", getenv("REMOTE_USER"));
+ FCGI_JSONPair("ip", getenv("REMOTE_ADDR"));
+ FCGI_EndJSON();
+}
+
+/**
+ * Generates a response to the client as described by the format parameter and
+ * extra arguments (exactly like printf). To be used when none of the other
+ * predefined functions will work exactly as needed. Extra care should be taken
+ * to ensure the correctness of the output.
+ * @param format The format string
+ * @param ... Any extra arguments as required by the format string.
+ */
+void FCGI_PrintRaw(const char *format, ...)
+{
+ va_list list;
+ va_start(list, format);
+ vprintf(format, list);
+ va_end(list);
+}
+
/**
* Main FCGI request loop that receives/responds to client requests.
- * @param data A data field to be passed to the selected module handler.
+ * @param data Reserved.
+ * @returns NULL (void* required for consistency with pthreads, although at the moment this runs in the main thread anyway)
+ * TODO: Get this to exit with the rest of the program!
*/
-void FCGI_RequestLoop (void * data)
+void * FCGI_RequestLoop (void *data)
{
- int count = 0;
- while (FCGI_Accept() >= 0) {
+ FCGIContext context = {0};
+
+ Log(LOGDEBUG, "First request...");
+ //TODO: The FCGI_Accept here is blocking.
+ // That means that if another thread terminates the program, this thread
+ // will not terminate until the next request is made.
+ while (FCGI_Accept() >= 0) {
+
+ if (Thread_Runstate() != RUNNING)
+ {
+ //TODO: Yeah... deal with this better :P
+ Log(LOGERR, "FIXME; FCGI gets request after other threads have finished.");
+ printf("Content-type: text/plain\r\n\r\n+++OUT OF CHEESE ERROR+++\n");
+ break;
+ }
+
+ Log(LOGDEBUG, "Got request #%d", context.response_number);
ModuleHandler module_handler = NULL;
char module[BUFSIZ], params[BUFSIZ];
-
+
//strncpy doesn't zero-truncate properly
snprintf(module, BUFSIZ, "%s", getenv("DOCUMENT_URI_LOCAL"));
snprintf(params, BUFSIZ, "%s", getenv("QUERY_STRING"));
size_t lastchar = strlen(module) - 1;
if (lastchar > 0 && module[lastchar] == '/')
module[lastchar] = 0;
-
- if (!strcmp("sensors", module)) {
- module_handler = SensorHandler;
- } else if (!strcmp("login", module)) {
- module_handler = LoginHandler;
- } else if (!strcmp("actuators", module)) {
-
+ //Default to the 'identify' module if none specified
+ if (!*module)
+ strcpy(module, "identify");
+
+ if (!strcmp("identify", module)) {
+ module_handler = IdentifyHandler;
+ } else if (!strcmp("control", module)) {
+ module_handler = Control_Handler;
+ } else if (!strcmp("sensors", module)) {
+ module_handler = Sensor_Handler;
}
+ context.current_module = module;
if (module_handler) {
- module_handler(data, params);
+ module_handler(&context, params);
} else {
- char buf[BUFSIZ];
-
- FCGI_BeginJSON(400, module);
- FCGI_BuildJSON("description", "400 Invalid response");
- snprintf(buf, BUFSIZ, "%d", count);
- FCGI_BuildJSON("request-number", buf);
- FCGI_BuildJSON("params", params);
- FCGI_BuildJSON("host", getenv("SERVER_HOSTNAME"));
- FCGI_BuildJSON("user", getenv("REMOTE_USER"));
- FCGI_BuildJSON("userip", getenv("REMOTE_ADDR"));
- FCGI_EndJSON();
+ FCGI_RejectJSON(&context, "Unhandled module");
}
+ context.response_number++;
- count++;
+ Log(LOGDEBUG, "Waiting for request #%d", context.response_number);
}
+
+ Log(LOGDEBUG, "Thread exiting.");
+ Thread_QuitProgram(false);
+ // NOTE: Don't call pthread_exit, because this runs in the main thread. Just return.
+ return NULL;
}