/**
* @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 <time.h>
+#include <stdarg.h>
#include "common.h"
#include "sensor.h"
-#include "log.h"
+#include "control.h"
#include "options.h"
-#define LOGIN_TIMEOUT 180
+/**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 logged-in user access*/
- time_t login_timestamp;
- char login_key[41];
- char login_ip[16];
+ /**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?**/
};
/**
- * Handles user logins.
+ * 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 parameters
- */
-static void LoginHandler(FCGIContext *context, char *params) {
- const char *key, *value;
- bool force = 0, end = 0;
+ * @param params User specified paramters: [actuators, sensors]
+ */
+static void IdentifyHandler(FCGIContext *context, char *params) {
+ bool ident_sensors = false, ident_actuators = false;
- while ((params = FCGI_KeyPair(params, &key, &value))) {
- if (!strcmp(key, "force"))
- force = !force;
- else if (!strcmp(key, "end"))
- end = !end;
- }
+ int i;
- if (end) {
- *(context->login_key) = 0;
- FCGI_BeginJSON(context, STATUS_OK);
- FCGI_EndJSON();
+ FCGIValue values[2] = {{"sensors", &ident_sensors, FCGI_BOOL_T},
+ {"actuators", &ident_actuators, FCGI_BOOL_T}};
+ if (!FCGI_ParseRequest(context, params, values, 2))
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);
+
+ //Sensor and actuator information
+ if (ident_sensors) {
+ 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 (ident_actuators) {
+ 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 || !*(context->login_key) ||
- (now - context->login_timestamp > LOGIN_TIMEOUT))
- {
+ 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);
- context->login_timestamp = now;
+ context->control_timestamp = now;
for (i = 0; i < 20; i++)
- sprintf(context->login_key + i * 2, "%02x", sha1[i]);
- snprintf(context->login_ip, 16, "%s", getenv("REMOTE_ADDR"));
+ 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->login_key);
- FCGI_EndJSON();
+ FCGI_JSONPair("key", context->control_key);
+ FCGI_EndJSON();
} else {
char buf[128];
strftime(buf, 128, "%H:%M:%S %d-%m-%Y",
- localtime(&(context->login_timestamp)));
- FCGI_BeginJSON(context, STATUS_UNAUTHORIZED);
- FCGI_JSONPair("description", "Already logged in");
- FCGI_JSONPair("user", context->login_ip);
- FCGI_JSONPair("time", buf);
- FCGI_EndJSON();
- }
-}
-
-/*TODO: Remove and replace with the actual actuator code*/
-static void ActuatorHandler(FCGIContext *context, char *params) {
- const char *key, *value, *loginkey = NULL;
- while ((params = FCGI_KeyPair(params, &key, &value))) {
- if (!strcmp(key, "key")) {
- loginkey = value;
- }
- }
- if (!loginkey || !FCGI_Authorized(context, loginkey)) {
+ localtime(&(context->control_timestamp)));
FCGI_BeginJSON(context, STATUS_UNAUTHORIZED);
- FCGI_JSONPair("description", "Invalid key specified.");
- FCGI_EndJSON();
- } else {
- FCGI_BeginJSON(context, STATUS_OK);
- FCGI_JSONPair("description", "Logged in!");
+ FCGI_JSONPair("description", "Another user already has control");
+ FCGI_JSONPair("current_user", context->control_ip);
+ FCGI_JSONPair("when", buf);
FCGI_EndJSON();
}
}
/**
* Given an FCGIContext, determines if the current user (as specified by
- * the key) is authorized or not. If validated, the context login_timestamp is
+ * the key) has control or not. If validated, the context control_timestamp is
* updated.
* @param context The context to work in
- * @param key The login key to be validated.
+ * @param key The control key to be validated.
* @return TRUE if authorized, FALSE if not.
*/
-bool FCGI_Authorized(FCGIContext *context, const char *key) {
+bool FCGI_HasControl(FCGIContext *context, const char *key) {
time_t now = time(NULL);
- int result = (now - context->login_timestamp) <= LOGIN_TIMEOUT &&
- !strcmp(context->login_key, key);
+ int result = (now - context->control_timestamp) <= CONTROL_TIMEOUT &&
+ key != NULL && !strcmp(context->control_key, key);
if (result) {
- context->login_timestamp = now; //Update the login_timestamp
+ context->control_timestamp = now; //Update the control_timestamp
}
return result;
}
+
+/**
+ * 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;
+}
+
/**
* Extracts a key/value pair from a request string.
* Note that the input is modified by this function.
return ptr;
}
+/**
+ * Aids in parsing request parameters. Expected keys along with their type
+ * and whether or not they're required are provided. This function will then
+ * parse the parameter string to find these keys.
+ * @param context The context to work in
+ * @param params The parameter string to be parsed
+ * @param values An array of FCGIValue's that specify expected keys
+ * @param count The number of elements in 'values'.
+ * @return true If the parameter string was parsed successfully, false otherwise.
+ * Modes of failure include: Invalid a parsing error on the value,
+ * an unknown key is specified,
+ * a key/value pair is specified more than once, or
+ * not all required keys were present.
+ * If this function returns false, it is guaranteed that FCGI_RejectJSON
+ * has already been called with the appropriate description message.
+ */
+bool FCGI_ParseRequest(FCGIContext *context, char *params, FCGIValue values[], size_t count)
+{
+ const char *key, *value;
+ char buf[BUFSIZ], *ptr;
+ size_t i;
+
+ while ((params = FCGI_KeyPair(params, &key, &value))) {
+ for (i = 0; i < count; i++) {
+ if (!strcmp(key, values[i].key)) {
+ FCGIValue *val = &values[i];
+
+ if (FCGI_RECEIVED(val->flags)) {
+ snprintf(buf, BUFSIZ, "Value already specified for '%s'.", key);
+ FCGI_RejectJSON(context, buf);
+ return false;
+ }
+ val->flags |= FCGI_PARAM_RECEIVED;
+
+ switch(FCGI_TYPE(val->flags)) {
+ case FCGI_BOOL_T:
+ *((bool*) val->value) = true;
+ break;
+ case FCGI_INT_T: case FCGI_LONG_T: {
+ long parsed = strtol(value, &ptr, 10);
+ if (!*value || *ptr) {
+ snprintf(buf, BUFSIZ, "Expected int for '%s' but got '%s'", key, value);
+ FCGI_RejectJSON(context, FCGI_EscapeJSON(buf));
+ return false;
+ }
+
+ if (FCGI_TYPE(val->flags) == FCGI_INT_T)
+ *((int*) val->value) = parsed;
+ else
+ *((long*) val->value) = parsed;
+ } break;
+ case FCGI_DOUBLE_T:
+ *((double*) val->value) = strtod(value, &ptr);
+ if (!*value || *ptr) {
+ snprintf(buf, BUFSIZ, "Expected float for '%s' but got '%s'", key, value);
+ FCGI_RejectJSON(context, FCGI_EscapeJSON(buf));
+ return false;
+ }
+ break;
+ case FCGI_STRING_T:
+ *((const char**) val->value) = value;
+ break;
+ default:
+ Fatal("Invalid type %d given", FCGI_TYPE(val->flags));
+ }
+ break; //No need to search any more
+ }
+ } //End for loop
+ if (i == count) {
+ snprintf(buf, BUFSIZ, "Unknown key '%s' specified", key);
+ FCGI_RejectJSON(context, FCGI_EscapeJSON(buf));
+ return false;
+ }
+ }
+
+ //Check that required parameters are received
+ for (i = 0; i < count; i++) {
+ if (FCGI_IS_REQUIRED(values[i].flags) && !FCGI_RECEIVED(values[i].flags)) {
+ snprintf(buf, BUFSIZ, "Key '%s' required, but was not given.", values[i].key);
+ FCGI_RejectJSON(context, buf);
+ return false;
+ }
+ }
+ return true;
+}
+
/**
* Begins a response to the client in JSON format.
* @param context The context to work in.
printf("{\r\n");
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);
+ //Time and running statistics
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);
-
+ FCGI_JSONDouble("start_time", TIMEVAL_TO_DOUBLE(g_options.start_time));
+ FCGI_JSONDouble("current_time", TIMEVAL_TO_DOUBLE(now));
+ FCGI_JSONDouble("running_time", TIMEVAL_DIFF(now, g_options.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.
+ * been initiated by FCGI_BeginJSON. Special 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_JSONPair(const char *key, const char *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.
}
/**
- * Should be used to write out the value of a JSON key. This has
- * the same format as the printf functions. Care should be taken to format
- * the output in valid JSON.
+ * Ends a JSON response that was initiated by FCGI_BeginJSON.
*/
-void FCGI_JSONValue(const char *format, ...)
+void FCGI_EndJSON()
{
- va_list list;
- va_start(list, format);
- vprintf(format, list);
- va_end(list);
+ printf("\r\n}\r\n");
}
/**
- * Ends a JSON response that was initiated by FCGI_BeginJSON.
+ * Escapes a string so it can be used as a JSON string value.
+ * Does not support unicode specifiers in the form of \uXXXX.
+ * @param buf The string to be escaped
+ * @return The escaped string (return value == buf)
*/
-void FCGI_EndJSON()
+char *FCGI_EscapeJSON(char *buf)
{
- printf("\r\n}\r\n");
+ int length, i;
+ length = strlen(buf);
+
+ //Escape special characters. Must count down to escape properly
+ for (i = length - 1; i >= 0; i--) {
+ if (buf[i] < 0x20) { //Control characters
+ buf[i] = ' ';
+ } else if (buf[i] == '"') {
+ if (i-1 >= 0 && buf[i-1] == '\\')
+ i--;
+ else
+ buf[i] = '\'';
+ } else if (buf[i] == '\\') {
+ if (i-1 >= 0 && buf[i-1] == '\'')
+ i--;
+ else
+ buf[i] = ' ';
+ }
+ }
+ return buf;
}
/**
- * To be used when the input parameters are invalid.
- * Sends a response with HTTP status 400 Bad request, along with
- * JSON data for debugging.
+ * 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 params The parameters that the module handler received.
+ * @param status The status the return data should have.
+ * @param description A short description of why the input was rejected.
*/
-void FCGI_RejectJSON(FCGIContext *context)
+void FCGI_RejectJSONEx(FCGIContext *context, StatusCodes status, const char *description)
{
- printf("Status: 400 Bad Request\r\n");
+ if (description == NULL)
+ description = "Unknown";
- FCGI_BeginJSON(context, STATUS_ERROR);
- FCGI_JSONPair("description", "Invalid request");
+ 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_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 Reserved.
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];
size_t lastchar = strlen(module) - 1;
if (lastchar > 0 && module[lastchar] == '/')
module[lastchar] = 0;
-
- if (!strcmp("login", module)) {
- module_handler = LoginHandler;
+ //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;
- } else if (!strcmp("actuators", module)) {
- module_handler = ActuatorHandler;
}
context.current_module = module;
if (module_handler) {
module_handler(&context, params);
} else {
- strncat(module, " [unknown]", BUFSIZ);
- FCGI_RejectJSON(&context);
+ FCGI_RejectJSON(&context, "Unhandled module");
}
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;
-
-
}