bird-lg/main.c

#define HTTPSERVER_IMPL

#define LOG_ENABLE_TRACE 1

#include <stdbool.h>
#include "httpserver.h"
#include <stdlib.h>
#include "favicon.h"
#include "string.h"
#include "bird.h"
#include "logging.h"


#define TRACEROUTE "traceroute -%s -A -q1 -N32 -w1 -m15 %s"

#define ERROR_NO_BIRD_SOCKET_CONFIGURED "no bird socket configured"
#define ERROR_BIRD_CONNECTION_FAILED "connection to bird daemon failed"


const char * config_ipv4_source;
const char * config_ipv6_source;
const char * bird_socket_path;
const char * bird6_socket_path;

const char * security_shared_secret;
string_view * security_access_list;
size_t security_access_list_length;



int request_target_is(http_request_t* request, char const * target) {
    http_string_t url = http_request_path(request);
    int len = strlen(target);
    return len == url.len && memcmp(url.buf, target, url.len) == 0;
}

int request_is_get(http_request_t* request) {
    http_string_t method = http_request_method(request);
    return method.len == 3 && memcmp(method.buf, "GET", method.len) == 0; 
}





void handle_traceroute(http_request_t* request, http_response_t* response, bool ipv6, string_view* query) {
    
    http_response_header(response, "Content-Type", "text/plain");
    
    // TODO: use strings
    
    FILE *fp;
    char buf[256];

    char* command = malloc(sizeof(TRACEROUTE) + query->len);
    assert(command != NULL /* command allocation was successful */);
    char* destination = malloc(query->len + 1);
    assert(command != NULL /* destination allocation was successful */);
    memcpy(destination, query->buf, query->len);
    destination[query->len] = '\0';
    
    sprintf(command, TRACEROUTE, ipv6 ? "6" : "4", destination); 
    
    /* Open the command for reading. */ 
    fp = popen(command, "r");
    if (fp == NULL) {
        http_response_status(response, 500);
        http_response_body(response, "traceroute failed", sizeof("traceroute failed") - 1);
        http_respond(request, response);
    } else {
        string str = string_init(0);
        /* Read the output a line at a time - output it. */
        while (fgets(buf, sizeof(buf), fp) != NULL) {
            string_append(str, buf);
        }

        /* close */
        pclose(fp);
        
        http_response_status(response, 200);
        http_response_body(response, str->buf, str->len);
        
        http_respond(request, response);
        string_free(str);
    }
}

void handle_bird(http_request_t* request, http_response_t* response, bool ipv6, string_view* query) {
    http_response_header(response, "Content-Type", "text/plain");
    
    const char * socket_path = ipv6 ? bird6_socket_path : bird_socket_path;
    if (socket_path == NULL) {
        http_response_status(response, 500);
        http_response_body(response, ERROR_NO_BIRD_SOCKET_CONFIGURED, sizeof(ERROR_NO_BIRD_SOCKET_CONFIGURED) - 1);
        http_respond(request, response);
    } else {
        bird_connection bird = bird_connect_uds(socket_path);
        if (bird == -1) {
            http_response_status(response, 500);
            http_response_body(response, ERROR_BIRD_CONNECTION_FAILED, sizeof(ERROR_BIRD_CONNECTION_FAILED) - 1);
            http_respond(request, response);
        } else {
            bird_response bird_res = bird_command(bird, query);
            // todo: use status? depends whether the lg main application expects an error status code when command failed
            http_response_status(response, 200);
            http_response_body(response, bird_res.message->buf, bird_res.message->len);
            http_respond(request, response);
            bird_free_response(bird_res);
        }
    }
}

void handle_favicon(http_request_t* request, http_response_t* response) {
    http_response_status(response, 200);
    http_response_header(response, "Content-Type", "image/x-icon");
    http_response_body(response, favicon_ico, favicon_ico_len);
    http_respond(request, response);
}

void handle_request(http_request_t* request) {
    http_response_t* response = http_response_init();
    
    
    if (!request_is_get(request)) {
        http_response_status(response, 405);
        http_respond(request, response);
    } else {
        if (request_target_is(request, "/favicon.ico")) {
            handle_favicon(request, response);
        } else {
            http_string_t query = http_request_query(request, "q");
            string query_decoded = string_urldecode(&HTTP_STR_TO_VIEW(query));
            if (query_decoded == NULL) {
                http_response_status(response, 400);
                http_respond(request, response);
            } else {
                if (request_target_is(request, "/traceroute")) {
                    handle_traceroute(request, response, false, (string_view*)query_decoded);
                } else if (request_target_is(request, "/traceroute6")) {
                    handle_traceroute(request, response, true, (string_view*)query_decoded);
                } else if (request_target_is(request, "/bird")) {
                    handle_bird(request, response, false, (string_view*)query_decoded);
                } else if (request_target_is(request, "/bird6")) {
                    handle_bird(request, response, true, (string_view*)query_decoded);
                } else {
                    http_response_status(response, 404);
                    http_respond(request, response);
                }
                string_free(query_decoded);
            }
        }
    }
    
}

int main() {
    const char * log_level_str = getenv("LOG_LEVEL");
    if (log_level_str != NULL) {
        log_level = atoi(log_level_str);
    }
    
    const char * bind_ip = getenv("BIND_IP");
    const char * bind_port = getenv("BIND_PORT");
    bird_socket_path = getenv("BIRD_SOCKET");
    bird6_socket_path = getenv("BIRD6_SOCKET");
    
    config_ipv4_source = getenv("IPV4_SOURCE");
    config_ipv6_source = getenv("IPV6_SOURCE");
    
    char * access_list = getenv("ACCESS_LIST");
    security_shared_secret = getenv("SHARED_SECRET");
    
    if (access_list != NULL) {
        string_view access_list_str = (string_view) {access_list, strlen(access_list)};
        security_access_list_length = string_split(&access_list_str, ',', &security_access_list); // don't care about freeing this since it's needed until the end of the program
    }
    
    
    if (bind_ip == NULL) {
        bind_ip = "0.0.0.0";
    }
    if (bind_port == NULL) {
        bind_port = "5000";
    }
    
    if (bird6_socket_path == NULL && bird_socket_path != NULL) {
        bird6_socket_path = bird_socket_path;
    } else if (bird_socket_path == NULL && bird6_socket_path != NULL) {
        bird_socket_path = bird6_socket_path;
    }
    
    int port = atoi(bind_port);
    // TODO: implement binding to an IP
    
    http_server_t* server = http_server_init(port, handle_request);
    http_server_listen(server);
}