Skip to content
Snippets Groups Projects
Normal view Permalink
http.c 11.6 KiB
Newer Older
Mark Spencer's avatar
Add micro-http server and abstract manager interface, make snmp not die
Mark Spencer committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 
/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

#include <sys/types.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <netinet/in.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/signal.h>
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <asterisk/cli.h>
#include <asterisk/http.h>
#include <asterisk/utils.h>
#include <asterisk/strings.h>

#define MAX_PREFIX 80
#define DEFAULT_PREFIX "asterisk"

/* This program implements a tiny http server supporting the "get" method
   only and was inspired by micro-httpd by Jef Poskanzer */

struct ast_http_server_instance {
	FILE *f;
	int fd;
	struct sockaddr_in requestor;
	ast_http_callback callback;
};

static struct ast_http_uri *uris;

static int httpfd = -1;
static pthread_t master = AST_PTHREADT_NULL;
static char prefix[MAX_PREFIX];
static int prefix_len = 0;
static struct sockaddr_in oldsin;


static char *httpstatus_callback(struct sockaddr_in *req, const char *uri, struct ast_variable *vars, int *status, char **title, int *contentlength)
{
	char result[4096];
	int reslen = sizeof(result);
	char *c=result;
	struct ast_variable *v;
	char iabuf[INET_ADDRSTRLEN];

	ast_build_string(&c, &reslen,
		"\r\n"
		"<title>Asterisk HTTP Status</title>\r\n"
		"<body bgcolor=\"#ffffff\">\r\n"
		"<table bgcolor=\"#f1f1f1\" align=\"center\"><tr><td bgcolor=\"#e0e0ff\" colspan=\"2\" width=\"500\">\r\n"
		"<h2>&nbsp;&nbsp;Asterisk&trade; HTTP Status</h2></td></tr>\r\n");

	ast_build_string(&c, &reslen, "<tr><td><i>Prefix</i></td><td><b>%s</b></td></tr>\r\n", prefix);
	ast_build_string(&c, &reslen, "<tr><td><i>Bind Address</i></td><td><b>%s</b></td></tr>\r\n",
			ast_inet_ntoa(iabuf, sizeof(iabuf), oldsin.sin_addr));
	ast_build_string(&c, &reslen, "<tr><td><i>Bind Port</i></td><td><b>%d</b></td></tr>\r\n",
			ntohs(oldsin.sin_port));
	ast_build_string(&c, &reslen, "<tr><td colspan=\"2\"><hr></td></tr>\r\n");
	v = vars;
	while(v) {
		ast_build_string(&c, &reslen, "<tr><td><i>Submitted Variable '%s'</i></td><td>%s</td></tr>\r\n", v->name, v->value);
		v = v->next;
	}
	ast_build_string(&c, &reslen, "</table><center><font size=\"-1\"><i>Asterisk and Digium are registered trademarks of Digium, Inc.</i></font></center></body>\r\n");
	return strdup(result);
}

static struct ast_http_uri statusuri = {
	.callback = httpstatus_callback,
	.description = "Asterisk HTTP General Status",
	.uri = "httpstatus",
	.has_subtree = 0,
};
	
char *ast_http_error(int status, const char *title, const char *extra_header, const char *text)
{
	char *c = NULL;
	asprintf(&c,
		"Content-type: text/html\r\n"
		"%s"
		"\r\n"
		"<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\r\n"
		"<html><head>\r\n"
		"<title>%d %s</title>\r\n"
		"</head><body>\r\n"
		"<h1>%s</h1>\r\n"
		"<p>%s</p>\r\n"
		"<hr />\r\n"
		"<address>Asterisk Server</address>\r\n"
		"</body></html>\r\n",
			(extra_header ? extra_header : ""), status, title, title, text);
	return c;
}

int ast_http_uri_link(struct ast_http_uri *urih)
{
	struct ast_http_uri *prev=uris;
	if (!uris || strlen(uris->uri) <= strlen(urih->uri)) {
		urih->next = uris;
		uris = urih;
	} else {
		while (prev->next && (strlen(prev->next->uri) > strlen(urih->uri)))
			prev = prev->next;
		/* Insert it here */
		urih->next = prev->next;
		prev->next = urih;
	}
	return 0;
}	

void ast_http_uri_unlink(struct ast_http_uri *urih)
{
	struct ast_http_uri *prev = uris;
	if (!uris)
		return;
	if (uris == urih) {
		uris = uris->next;
	}
	while(prev->next) {
		if (prev->next == urih) {
			prev->next = urih->next;
			break;
		}
		prev = prev->next;
	}
}

static char *handle_uri(struct sockaddr_in *sin, char *uri, int *status, char **title, int *contentlength)
{
	char *c;
	char *turi;
	char *params;
	char *var;
	char *val;
	struct ast_http_uri *urih=NULL;
	int len;
	struct ast_variable *vars=NULL, *v, *prev = NULL;
	
	
	if (*uri == '/')
		uri++;
	params = strchr(uri, '?');
	if (params) {
		*params = '\0';
		params++;
		while ((var = strsep(&params, "&"))) {
			val = strchr(var, '=');
			if (val) {
				*val = '\0';
				val++;
			} else 
				val = "";
			ast_uri_decode(val);
			ast_uri_decode(var);
			if ((v = ast_variable_new(var, val))) {
				if (vars)
					prev->next = v;
				else
					vars = v;
				prev = v;
			}
		}
	}
	ast_uri_decode(uri);
	if (!strncasecmp(uri, prefix, prefix_len)) {
		uri += prefix_len;
		if (!*uri || (*uri == '/')) {
			if (*uri == '/')
				uri++;
			urih = uris;
			while(urih) {
				len = strlen(urih->uri);
				if (!strncasecmp(urih->uri, uri, len)) {
					if (!uri[len] || uri[len] == '/') {
						turi = uri + len;
						if (*turi == '/')
							turi++;
						if (!*turi || urih->has_subtree) {
							uri = turi;
							break;
						}
					}
				}
				urih = urih->next;
			}
		}
	}
	if (urih) {
		c = urih->callback(sin, uri, vars, status, title, contentlength);
		ast_variables_destroy(vars);
	} else {
		c = ast_http_error(404, "Not Found", NULL, "The requested URL was not found on this serer.");
		*status = 404;
		*title = strdup("Not Found");
	}
	return c;
}

static void *ast_httpd_helper_thread(void *data)
{
	char buf[4096];
	char timebuf[256];
	struct ast_http_server_instance *ser = data;
	char *uri, *c, *title=NULL;
	int status = 200, contentlength = 0;
	time_t t;

	if (fgets(buf, sizeof(buf), ser->f)) {
		/* Skip method */
		uri = buf;
		while(*uri && (*uri > 32)) uri++;
		if (*uri) {
			*uri = '\0';
			uri++;
		}

		/* Skip white space */
		while (*uri && (*uri < 33)) uri++;

		if (*uri) {
			c = uri;
			while (*c && (*c > 32)) c++;
			if (*c) {
				*c = '\0';
			}
		}
		if (*uri) {
			if (!strcasecmp(buf, "get")) 
				c = handle_uri(&ser->requestor, uri, &status, &title, &contentlength);
			else 
				c = ast_http_error(501, "Not Implemented", NULL, "Attempt to use unimplemented / unsupported method");\
		} else 
			c = ast_http_error(400, "Bad Request", NULL, "Invalid Request");
		if (!c)
			c = ast_http_error(500, "Internal Error", NULL, "Internal Server Error");
		if (c) {
			time(&t);
			strftime(timebuf, sizeof(timebuf), "%a, %d %b %Y %H:%M:%S GMT", gmtime(&t));
			ast_cli(ser->fd, "HTTP/1.1 GET %d %s\r\n", status, title ? title : "OK");
			ast_cli(ser->fd, "Server: Asterisk\r\n");
			ast_cli(ser->fd, "Date: %s\r\n", timebuf);
			if (contentlength)
				ast_cli(ser->fd, "Content-length: %d\r\n", contentlength);
			ast_cli(ser->fd, "Connection: close\r\n");
			ast_cli(ser->fd, "%s", c);
			free(c);
		}
		if (title)
			free(title);
	}
	fclose(ser->f);
	free(ser);
	return NULL;
}

static void *http_root(void *data)
{
	int fd;
	struct sockaddr_in sin;
	int sinlen;
	struct ast_http_server_instance *ser;
	pthread_t launched;
	for (;;) {
		ast_wait_for_input(httpfd, -1);
		sinlen = sizeof(sin);
		fd = accept(httpfd, (struct sockaddr *)&sin, &sinlen);
		if (fd < 0) {
			if ((errno != EAGAIN) && (errno != EINTR))
				ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
			continue;
		}
		ser = calloc(1, sizeof(*ser));
		if (ser) {
			ser->fd = fd;
			if ((ser->f = fdopen(ser->fd, "w+"))) {
				if (ast_pthread_create(&launched, NULL, ast_httpd_helper_thread, ser)) {
					ast_log(LOG_WARNING, "Unable to launch helper thread: %s\n", strerror(errno));
					fclose(ser->f);
					free(ser);
				}
			} else {
				ast_log(LOG_WARNING, "fdopen failed!\n");
				close(ser->fd);
				free(ser);
			}
		} else {
			ast_log(LOG_WARNING, "Out of memory!\n");
			close(fd);
		}
	}
	return NULL;
}

static void http_server_start(struct sockaddr_in *sin)
{
	char iabuf[INET_ADDRSTRLEN];
	int flags;
	int x = 1;
	
	/* Do nothing if nothing has changed */
	if (!memcmp(&oldsin, sin, sizeof(oldsin))) {
		ast_log(LOG_DEBUG, "Nothing changed in http\n");
		return;
	}
	
	memcpy(&oldsin, sin, sizeof(oldsin));
	
	/* Shutdown a running server if there is one */
	if (master != AST_PTHREADT_NULL) {
		pthread_cancel(master);
		pthread_kill(master, SIGURG);
		pthread_join(master, NULL);
	}
	
	if (httpfd != -1)
		close(httpfd);

	/* If there's no new server, stop here */
	if (!sin->sin_family)
		return;
	
	
	httpfd = socket(AF_INET, SOCK_STREAM, 0);
	if (httpfd < 0) {
		ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
		return;
	}
	
	setsockopt(httpfd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
	if (bind(httpfd, (struct sockaddr *)sin, sizeof(*sin))) {
		ast_log(LOG_NOTICE, "Unable to bind http server to %s:%d: %s\n",
			ast_inet_ntoa(iabuf, sizeof(iabuf), sin->sin_addr), ntohs(sin->sin_port),
			strerror(errno));
		close(httpfd);
		httpfd = -1;
		return;
	}
	if (listen(httpfd, 10)) {
		ast_log(LOG_NOTICE, "Unable to listen!\n");
		close(httpfd);
		httpfd = -1;
		return;
	}
	flags = fcntl(httpfd, F_GETFL);
	fcntl(httpfd, F_SETFL, flags | O_NONBLOCK);
	if (ast_pthread_create(&master, NULL, http_root, NULL)) {
		ast_log(LOG_NOTICE, "Unable to launch http server on %s:%d: %s\n",
				ast_inet_ntoa(iabuf, sizeof(iabuf), sin->sin_addr), ntohs(sin->sin_port),
				strerror(errno));
		close(httpfd);
		httpfd = -1;
	}
}

static int __ast_http_load(int reload)
{
	struct ast_config *cfg;
	struct ast_variable *v;
	int enabled=0;
	struct sockaddr_in sin;
	struct hostent *hp;
	struct ast_hostent ahp;
	char newprefix[MAX_PREFIX];
	memset(&sin, 0, sizeof(sin));
	sin.sin_port = 8088;
	strcpy(newprefix, DEFAULT_PREFIX);
	cfg = ast_config_load("http.conf");
	if (cfg) {
		v = ast_variable_browse(cfg, "general");
		while(v) {
			if (!strcasecmp(v->name, "enabled"))
				enabled = ast_true(v->value);
			else if (!strcasecmp(v->name, "bindport"))
				sin.sin_port = ntohs(atoi(v->value));
			else if (!strcasecmp(v->name, "bindaddr")) {
				if ((hp = ast_gethostbyname(v->value, &ahp))) {
					memcpy(&sin.sin_addr, hp->h_addr, sizeof(sin.sin_addr));
				} else {
					ast_log(LOG_WARNING, "Invalid bind address '%s'\n", v->value);
				}
			} else if (!strcasecmp(v->name, "prefix"))
				ast_copy_string(newprefix, v->value, sizeof(newprefix));
			v = v->next;
		}
		ast_config_destroy(cfg);
	}
	if (enabled)
		sin.sin_family = AF_INET;
	if (strcmp(prefix, newprefix)) {
		ast_copy_string(prefix, newprefix, sizeof(prefix));
		prefix_len = strlen(prefix);
	}
	http_server_start(&sin);
	return 0;
}

static int handle_show_http(int fd, int argc, char *argv[])
{
	char iabuf[INET_ADDRSTRLEN];
	struct ast_http_uri *urih;
	if (argc != 2)
		return RESULT_SHOWUSAGE;
	ast_cli(fd, "HTTP Server Status:\n");
	ast_cli(fd, "Prefix: %s\n", prefix);
	if (oldsin.sin_family)
		ast_cli(fd, "Server Enabled and Bound to %s:%d\n\n",
			ast_inet_ntoa(iabuf, sizeof(iabuf), oldsin.sin_addr),
			ntohs(oldsin.sin_port));
	else
		ast_cli(fd, "Server Disabled\n\n");
	ast_cli(fd, "Enabled URI's:\n");
	urih = uris;
	while(urih){
		ast_cli(fd, "/%s/%s%s => %s\n", prefix, urih->uri, (urih->has_subtree ? "/..." : "" ), urih->description);
		urih = urih->next;
	}
	if (!uris)
		ast_cli(fd, "None.\n");
	return RESULT_SUCCESS;
}

int ast_http_reload(void)
{
	return __ast_http_load(1);
}

static char show_http_help[] =
"Usage: show http\n"
"       Shows status of internal HTTP engine\n";

static struct ast_cli_entry http_cli[] = {
	{ { "show", "http", NULL }, handle_show_http,
	  "Display HTTP status", show_http_help },
};

int ast_http_init(void)
{
	ast_http_uri_link(&statusuri);
	ast_cli_register_multiple(http_cli, sizeof(http_cli) / sizeof(http_cli[0]));
	return __ast_http_load(0);
}