/*
 * libwebsockets-test-server - libwebsockets test implementation
 *
 * Copyright (C) 2010-2016 Andy Green <andy@warmcat.com>
 *
 * This file is made available under the Creative Commons CC0 1.0
 * Universal Public Domain Dedication.
 *
 * The person who associated a work with this deed has dedicated
 * the work to the public domain by waiving all of his or her rights
 * to the work worldwide under copyright law, including all related
 * and neighboring rights, to the extent allowed by law. You can copy,
 * modify, distribute and perform the work, even for commercial purposes,
 * all without asking permission.
 *
 * The test apps are intended to be adapted for use in your code, which
 * may be proprietary.  So unlike the library itself, they are licensed
 * Public Domain.
 */
#include "test-server.h"

/*
 * This demo server shows how to use libwebsockets for one or more
 * websocket protocols in the same server
 *
 * It defines the following websocket protocols:
 *
 *  dumb-increment-protocol:  once the socket is opened, an incrementing
 *				ascii string is sent down it every 50ms.
 *				If you send "reset\n" on the websocket, then
 *				the incrementing number is reset to 0.
 *
 *  lws-mirror-protocol: copies any received packet to every connection also
 *				using this protocol, including the sender
 */

#if defined(LWS_USE_POLARSSL)
#else
#if defined(LWS_USE_MBEDTLS)
#else
#if defined(LWS_OPENSSL_SUPPORT) && defined(LWS_HAVE_SSL_CTX_set1_param)
/* location of the certificate revocation list */
extern char crl_path[1024];
#endif
#endif
#endif

extern int debug_level;

enum demo_protocols {
	/* always first */
	PROTOCOL_HTTP = 0,

	PROTOCOL_DUMB_INCREMENT,
	PROTOCOL_LWS_MIRROR,

	/* always last */
	DEMO_PROTOCOL_COUNT
};

/*
 * We take a strict whitelist approach to stop ../ attacks
 */
struct serveable {
	const char *urlpath;
	const char *mimetype;
};

/*
 * this is just an example of parsing handshake headers, you don't need this
 * in your code unless you will filter allowing connections by the header
 * content
 */
void
dump_handshake_info(struct lws *wsi)
{
	int n = 0, len;
	char buf[256];
	const unsigned char *c;

	do {
		c = lws_token_to_string(n);
		if (!c) {
			n++;
			continue;
		}

		len = lws_hdr_total_length(wsi, n);
		if (!len || len > sizeof(buf) - 1) {
			n++;
			continue;
		}

		lws_hdr_copy(wsi, buf, sizeof buf, n);
		buf[sizeof(buf) - 1] = '\0';

		fprintf(stderr, "    %s = %s\n", (char *)c, buf);
		n++;
	} while (c);
}

const char * get_mimetype(const char *file)
{
	int n = strlen(file);

	if (n < 5)
		return NULL;

	if (!strcmp(&file[n - 4], ".ico"))
		return "image/x-icon";

	if (!strcmp(&file[n - 4], ".png"))
		return "image/png";

	if (!strcmp(&file[n - 5], ".html"))
		return "text/html";

	if (!strcmp(&file[n - 4], ".css"))
		return "text/css";

	return NULL;
}

/* this protocol server (always the first one) handles HTTP,
 *
 * Some misc callbacks that aren't associated with a protocol also turn up only
 * here on the first protocol server.
 */

int callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user,
		  void *in, size_t len)
{
	struct per_session_data__http *pss =
			(struct per_session_data__http *)user;
	unsigned char buffer[4096 + LWS_PRE];
	unsigned long amount, file_len, sent;
	char leaf_path[1024];
	const char *mimetype;
	char *other_headers;
	unsigned char *end, *start;
	struct timeval tv;
	unsigned char *p;
#ifndef LWS_NO_CLIENT
	struct per_session_data__http *pss1;
	struct lws *wsi1;
#endif
	char buf[256];
	char b64[64];
	int n, m;
#ifdef EXTERNAL_POLL
	struct lws_pollargs *pa = (struct lws_pollargs *)in;
#endif


	switch (reason) {
	case LWS_CALLBACK_HTTP:

		lwsl_notice("lws_http_serve: %s\n",in);

		if (debug_level & LLL_INFO) {
			dump_handshake_info(wsi);

			/* dump the individual URI Arg parameters */
			n = 0;
			while (lws_hdr_copy_fragment(wsi, buf, sizeof(buf),
						     WSI_TOKEN_HTTP_URI_ARGS, n) > 0) {
				lwsl_notice("URI Arg %d: %s\n", ++n, buf);
			}
		}

		{
			char name[100], rip[50];
			lws_get_peer_addresses(wsi, lws_get_socket_fd(wsi), name,
					       sizeof(name), rip, sizeof(rip));
			sprintf(buf, "%s (%s)", name, rip);
			lwsl_notice("HTTP connect from %s\n", buf);
		}

		if (len < 1) {
			lws_return_http_status(wsi,
						HTTP_STATUS_BAD_REQUEST, NULL);
			goto try_to_reuse;
		}

#ifndef LWS_NO_CLIENT
		if (!strncmp(in, "/proxytest", 10)) {
			struct lws_client_connect_info i;
			char *rootpath = "/";
			const char *p = (const char *)in;

			if (lws_get_child(wsi))
				break;

			pss->client_finished = 0;
			memset(&i,0, sizeof(i));
			i.context = lws_get_context(wsi);
			i.address = "git.libwebsockets.org";
			i.port = 80;
			i.ssl_connection = 0;
			if (p[10])
				i.path = (char *)in + 10;
			else
				i.path = rootpath;
			i.host = "git.libwebsockets.org";
			i.origin = NULL;
			i.method = "GET";
			i.parent_wsi = wsi;
			i.uri_replace_from = "git.libwebsockets.org/";
			i.uri_replace_to = "/proxytest/";
			if (!lws_client_connect_via_info(&i)) {
				lwsl_err("proxy connect fail\n");
				break;
			}



			break;
		}
#endif

#if 1
		/* this example server has no concept of directories */
		if (strchr((const char *)in + 1, '/')) {
			lws_return_http_status(wsi, HTTP_STATUS_NOT_ACCEPTABLE, NULL);
			goto try_to_reuse;
		}
#endif

		if (!strncmp(in, "/postresults", 12)) {
			m = sprintf(buf, "<html><body>Form results: '%s'<br>"
					"</body></html>", pss->post_string);

			p = buffer + LWS_PRE;
			start = p;
			end = p + sizeof(buffer) - LWS_PRE;

			if (lws_add_http_header_status(wsi, 200, &p, end))
				return 1;
			if (lws_add_http_header_by_token(wsi,
					WSI_TOKEN_HTTP_CONTENT_TYPE,
				    	(unsigned char *)"text/html",
					9, &p, end))
				return 1;
			if (lws_add_http_header_content_length(wsi, m, &p,
							       end))
				return 1;
			if (lws_finalize_http_header(wsi, &p, end))
				return 1;

			n = lws_write(wsi, start, p - start,
				      LWS_WRITE_HTTP_HEADERS);
			if (n < 0)
				return 1;

			n = lws_write(wsi, (unsigned char *)buf, m, LWS_WRITE_HTTP);
			if (n < 0)
				return 1;

			goto try_to_reuse;
		}

		/* if a legal POST URL, let it continue and accept data */
		if (lws_hdr_total_length(wsi, WSI_TOKEN_POST_URI))
			return 0;

		/* check for the "send a big file by hand" example case */

		if (!strcmp((const char *)in, "/leaf.jpg")) {
			if (strlen(resource_path) > sizeof(leaf_path) - 10)
				return -1;
			sprintf(leaf_path, "%s/leaf.jpg", resource_path);

			/* well, let's demonstrate how to send the hard way */

			p = buffer + LWS_PRE;
			end = p + sizeof(buffer) - LWS_PRE;

			pss->fd = lws_plat_file_open(wsi, leaf_path, &file_len,
						     LWS_O_RDONLY);

			if (pss->fd == LWS_INVALID_FILE) {
				lwsl_err("failed to open file %s\n", leaf_path);
				return -1;
			}

			/*
			 * we will send a big jpeg file, but it could be
			 * anything.  Set the Content-Type: appropriately
			 * so the browser knows what to do with it.
			 *
			 * Notice we use the APIs to build the header, which
			 * will do the right thing for HTTP 1/1.1 and HTTP2
			 * depending on what connection it happens to be working
			 * on
			 */
			if (lws_add_http_header_status(wsi, 200, &p, end))
				return 1;
			if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
				    	(unsigned char *)"libwebsockets",
					13, &p, end))
				return 1;
			if (lws_add_http_header_by_token(wsi,
					WSI_TOKEN_HTTP_CONTENT_TYPE,
				    	(unsigned char *)"image/jpeg",
					10, &p, end))
				return 1;
			if (lws_add_http_header_content_length(wsi,
							       file_len, &p,
							       end))
				return 1;
			if (lws_finalize_http_header(wsi, &p, end))
				return 1;

			/*
			 * send the http headers...
			 * this won't block since it's the first payload sent
			 * on the connection since it was established
			 * (too small for partial)
			 *
			 * Notice they are sent using LWS_WRITE_HTTP_HEADERS
			 * which also means you can't send body too in one step,
			 * this is mandated by changes in HTTP2
			 */

			*p = '\0';
			lwsl_info("%s\n", buffer + LWS_PRE);

			n = lws_write(wsi, buffer + LWS_PRE,
				      p - (buffer + LWS_PRE),
				      LWS_WRITE_HTTP_HEADERS);
			if (n < 0) {
				lws_plat_file_close(wsi, pss->fd);
				return -1;
			}
			/*
			 * book us a LWS_CALLBACK_HTTP_WRITEABLE callback
			 */
			lws_callback_on_writable(wsi);
			break;
		}

		/* if not, send a file the easy way */
		if (!strncmp(in, "/cgit-data/", 11)) {
			in = (char *)in + 11;
			strcpy(buf, "/usr/share/cgit");
		} else
			strcpy(buf, resource_path);

		if (strcmp(in, "/")) {
			if (*((const char *)in) != '/')
				strcat(buf, "/");
			strncat(buf, in, sizeof(buf) - strlen(buf) - 1);
		} else /* default file to serve */
			strcat(buf, "/test.html");
		buf[sizeof(buf) - 1] = '\0';

		/* refuse to serve files we don't understand */
		mimetype = get_mimetype(buf);
		if (!mimetype) {
			lwsl_err("Unknown mimetype for %s\n", buf);
			lws_return_http_status(wsi,
				      HTTP_STATUS_UNSUPPORTED_MEDIA_TYPE, NULL);
			return -1;
		}

		/* demonstrates how to set a cookie on / */

		other_headers = leaf_path;
		p = (unsigned char *)leaf_path;
		if (!strcmp((const char *)in, "/") &&
			   !lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_COOKIE)) {
			/* this isn't very unguessable but it'll do for us */
			gettimeofday(&tv, NULL);
			n = sprintf(b64, "test=LWS_%u_%u_COOKIE;Max-Age=360000",
				(unsigned int)tv.tv_sec,
				(unsigned int)tv.tv_usec);

			if (lws_add_http_header_by_name(wsi,
				(unsigned char *)"set-cookie:",
				(unsigned char *)b64, n, &p,
				(unsigned char *)leaf_path + sizeof(leaf_path)))
				return 1;
		}
		if (lws_is_ssl(wsi) && lws_add_http_header_by_name(wsi,
						(unsigned char *)
						"Strict-Transport-Security:",
						(unsigned char *)
						"max-age=15768000 ; "
						"includeSubDomains", 36, &p,
						(unsigned char *)leaf_path +
							sizeof(leaf_path)))
			return 1;
		n = (char *)p - leaf_path;

		n = lws_serve_http_file(wsi, buf, mimetype, other_headers, n);
		if (n < 0 || ((n > 0) && lws_http_transaction_completed(wsi)))
			return -1; /* error or can't reuse connection: close the socket */

		/*
		 * notice that the sending of the file completes asynchronously,
		 * we'll get a LWS_CALLBACK_HTTP_FILE_COMPLETION callback when
		 * it's done
		 */
		break;

	case LWS_CALLBACK_HTTP_BODY:
		lwsl_notice("LWS_CALLBACK_HTTP_BODY: len %d\n", (int)len);
		strncpy(pss->post_string, in, sizeof (pss->post_string) -1);
		pss->post_string[sizeof(pss->post_string) - 1] = '\0';
		if (len < sizeof(pss->post_string) - 1)
			pss->post_string[len] = '\0';
		break;

	case LWS_CALLBACK_HTTP_BODY_COMPLETION:
		lwsl_notice("LWS_CALLBACK_HTTP_BODY_COMPLETION\n");
		/*
		 * the whole of the sent body arrived,
		 * respond to the client with a redirect to show the
		 * results
		 */
		p = (unsigned char *)buf + LWS_PRE;
		n = lws_http_redirect(wsi,
				      HTTP_STATUS_SEE_OTHER, /* 303 */
				      (unsigned char *)"/postresults", 12, /* location + len */
				      &p, /* temp buffer to use */
				      p + sizeof(buf) - 1 - LWS_PRE /* buffer len */
			);
		goto try_to_reuse;

	case LWS_CALLBACK_HTTP_FILE_COMPLETION:
		goto try_to_reuse;

	case LWS_CALLBACK_HTTP_WRITEABLE:
		lwsl_info("LWS_CALLBACK_HTTP_WRITEABLE\n");

		if (pss->client_finished)
			return -1;

		if (pss->fd == LWS_INVALID_FILE)
			goto try_to_reuse;

#ifndef LWS_NO_CLIENT
		if (pss->reason_bf & 2) {
			char *px = buf + LWS_PRE;
			int lenx = sizeof(buf) - LWS_PRE;
			/*
			 * our sink is writeable and our source has something
			 * to read.  So read a lump of source material of
			 * suitable size to send or what's available, whichever
			 * is the smaller.
			 */
			pss->reason_bf &= ~2;
			wsi1 = lws_get_child(wsi);
			if (!wsi1)
				break;
			if (lws_http_client_read(wsi1, &px, &lenx) < 0)
				goto bail;

			if (pss->client_finished)
				return -1;
			break;
		}
#endif
		/*
		 * we can send more of whatever it is we were sending
		 */
		sent = 0;
		do {
			/* we'd like the send this much */
			n = sizeof(buffer) - LWS_PRE;

			/* but if the peer told us he wants less, we can adapt */
			m = lws_get_peer_write_allowance(wsi);

			/* -1 means not using a protocol that has this info */
			if (m == 0)
				/* right now, peer can't handle anything */
				goto later;

			if (m != -1 && m < n)
				/* he couldn't handle that much */
				n = m;

			n = lws_plat_file_read(wsi, pss->fd,
					       &amount, buffer + LWS_PRE, n);
			/* problem reading, close conn */
			if (n < 0) {
				lwsl_err("problem reading file\n");
				goto bail;
			}
			n = (int)amount;
			/* sent it all, close conn */
			if (n == 0)
				goto penultimate;
			/*
			 * To support HTTP2, must take care about preamble space
			 *
			 * identification of when we send the last payload frame
			 * is handled by the library itself if you sent a
			 * content-length header
			 */
			m = lws_write(wsi, buffer + LWS_PRE, n, LWS_WRITE_HTTP);
			if (m < 0) {
				lwsl_err("write failed\n");
				/* write failed, close conn */
				goto bail;
			}
			if (m) /* while still active, extend timeout */
				lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT, 5);
			sent += m;

		} while (!lws_send_pipe_choked(wsi) && (sent < 1024 * 1024));
later:
		lws_callback_on_writable(wsi);
		break;
penultimate:
		lws_plat_file_close(wsi, pss->fd);
		pss->fd = LWS_INVALID_FILE;
		goto try_to_reuse;

bail:
		lws_plat_file_close(wsi, pss->fd);

		return -1;

	/*
	 * callback for confirming to continue with client IP appear in
	 * protocol 0 callback since no websocket protocol has been agreed
	 * yet.  You can just ignore this if you won't filter on client IP
	 * since the default unhandled callback return is 0 meaning let the
	 * connection continue.
	 */
	case LWS_CALLBACK_FILTER_NETWORK_CONNECTION:
		/* if we returned non-zero from here, we kill the connection */
		break;

#ifndef LWS_NO_CLIENT
	case LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP: {
		char ctype[64], ctlen = 0;
		lwsl_err("LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP\n");
		p = buffer + LWS_PRE;
		end = p + sizeof(buffer) - LWS_PRE;
		if (lws_add_http_header_status(lws_get_parent(wsi), 200, &p, end))
			return 1;
		if (lws_add_http_header_by_token(lws_get_parent(wsi),
				WSI_TOKEN_HTTP_SERVER,
			    	(unsigned char *)"libwebsockets",
				13, &p, end))
			return 1;

		ctlen = lws_hdr_copy(wsi, ctype, sizeof(ctype), WSI_TOKEN_HTTP_CONTENT_TYPE);
		if (ctlen > 0) {
			if (lws_add_http_header_by_token(lws_get_parent(wsi),
				WSI_TOKEN_HTTP_CONTENT_TYPE,
				(unsigned char *)ctype, ctlen, &p, end))
				return 1;
		}
#if 0
		if (lws_add_http_header_content_length(lws_get_parent(wsi),
						       file_len, &p, end))
			return 1;
#endif
		if (lws_finalize_http_header(lws_get_parent(wsi), &p, end))
			return 1;

		*p = '\0';
		lwsl_info("%s\n", buffer + LWS_PRE);

		n = lws_write(lws_get_parent(wsi), buffer + LWS_PRE,
			      p - (buffer + LWS_PRE),
			      LWS_WRITE_HTTP_HEADERS);
		if (n < 0)
			return -1;

		break; }
	case LWS_CALLBACK_CLOSED_CLIENT_HTTP:
		//lwsl_err("LWS_CALLBACK_CLOSED_CLIENT_HTTP\n");
		return -1;
		break;
	case LWS_CALLBACK_RECEIVE_CLIENT_HTTP:
		//lwsl_err("LWS_CALLBACK_RECEIVE_CLIENT_HTTP: wsi %p\n", wsi);
		assert(lws_get_parent(wsi));
		if (!lws_get_parent(wsi))
			break;
		// lwsl_err("LWS_CALLBACK_RECEIVE_CLIENT_HTTP: wsi %p: sock: %d, parent_wsi: %p, parent_sock:%d,  len %d\n",
		//		wsi, lws_get_socket_fd(wsi),
		//		lws_get_parent(wsi),
		//		lws_get_socket_fd(lws_get_parent(wsi)), len);
		pss1 = lws_wsi_user(lws_get_parent(wsi));
		pss1->reason_bf |= 2;
		lws_callback_on_writable(lws_get_parent(wsi));
		break;
	case LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ:
		//lwsl_err("LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ len %d\n", len);
		assert(lws_get_parent(wsi));
		m = lws_write(lws_get_parent(wsi), (unsigned char *)in,
				len, LWS_WRITE_HTTP);
		if (m < 0)
			return -1;
		break;
	case LWS_CALLBACK_COMPLETED_CLIENT_HTTP:
		//lwsl_err("LWS_CALLBACK_COMPLETED_CLIENT_HTTP\n");
		assert(lws_get_parent(wsi));
		if (!lws_get_parent(wsi))
			break;
		pss1 = lws_wsi_user(lws_get_parent(wsi));
		pss1->client_finished = 1;
		break;
#endif

	/*
	 * callbacks for managing the external poll() array appear in
	 * protocol 0 callback
	 */

	case LWS_CALLBACK_LOCK_POLL:
		/*
		 * lock mutex to protect pollfd state
		 * called before any other POLL related callback
		 * if protecting wsi lifecycle change, len == 1
		 */
		test_server_lock(len);
		break;

	case LWS_CALLBACK_UNLOCK_POLL:
		/*
		 * unlock mutex to protect pollfd state when
		 * called after any other POLL related callback
		 * if protecting wsi lifecycle change, len == 1
		 */
		test_server_unlock(len);
		break;

#ifdef EXTERNAL_POLL
	case LWS_CALLBACK_ADD_POLL_FD:

		if (count_pollfds >= max_poll_elements) {
			lwsl_err("LWS_CALLBACK_ADD_POLL_FD: too many sockets to track\n");
			return 1;
		}

		fd_lookup[pa->fd] = count_pollfds;
		pollfds[count_pollfds].fd = pa->fd;
		pollfds[count_pollfds].events = pa->events;
		pollfds[count_pollfds++].revents = 0;
		break;

	case LWS_CALLBACK_DEL_POLL_FD:
		if (!--count_pollfds)
			break;
		m = fd_lookup[pa->fd];
		/* have the last guy take up the vacant slot */
		pollfds[m] = pollfds[count_pollfds];
		fd_lookup[pollfds[count_pollfds].fd] = m;
		break;

	case LWS_CALLBACK_CHANGE_MODE_POLL_FD:
	        pollfds[fd_lookup[pa->fd]].events = pa->events;
		break;
#endif

	case LWS_CALLBACK_GET_THREAD_ID:
		/*
		 * if you will call "lws_callback_on_writable"
		 * from a different thread, return the caller thread ID
		 * here so lws can use this information to work out if it
		 * should signal the poll() loop to exit and restart early
		 */

		/* return pthread_getthreadid_np(); */

		break;

#if defined(LWS_USE_POLARSSL)
#else
#if defined(LWS_USE_MBEDTLS)
#else
#if defined(LWS_OPENSSL_SUPPORT)
	case LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION:
		/* Verify the client certificate */
		if (!len || (SSL_get_verify_result((SSL*)in) != X509_V_OK)) {
			int err = X509_STORE_CTX_get_error((X509_STORE_CTX*)user);
			int depth = X509_STORE_CTX_get_error_depth((X509_STORE_CTX*)user);
			const char* msg = X509_verify_cert_error_string(err);
			lwsl_err("LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION: SSL error: %s (%d), depth: %d\n", msg, err, depth);
			return 1;
		}
		break;
#if defined(LWS_HAVE_SSL_CTX_set1_param)
	case LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS:
		if (crl_path[0]) {
			/* Enable CRL checking */
			X509_VERIFY_PARAM *param = X509_VERIFY_PARAM_new();
			X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK);
			SSL_CTX_set1_param((SSL_CTX*)user, param);
			X509_STORE *store = SSL_CTX_get_cert_store((SSL_CTX*)user);
			X509_LOOKUP *lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
			n = X509_load_cert_crl_file(lookup, crl_path, X509_FILETYPE_PEM);
			X509_VERIFY_PARAM_free(param);
			if (n != 1) {
				char errbuf[256];
				n = ERR_get_error();
				lwsl_err("LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS: SSL error: %s (%d)\n", ERR_error_string(n, errbuf), n);
				return 1;
			}
		}
		break;
#endif
#endif
#endif
#endif

	default:
		break;
	}

	return 0;

	/* if we're on HTTP1.1 or 2.0, will keep the idle connection alive */
try_to_reuse:
	if (lws_http_transaction_completed(wsi))
		return -1;

	return 0;
}