lighttpd1.4/src/connections.c

#include "first.h"

#include "buffer.h"
#include "server.h"
#include "log.h"
#include "connections.h"
#include "fdevent.h"

#include "configfile.h"
#include "request.h"
#include "response.h"
#include "network.h"
#include "http_chunk.h"
#include "stat_cache.h"
#include "joblist.h"

#include "plugin.h"

#include "inet_ntop_cache.h"

#include <sys/stat.h>

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <assert.h>

#ifdef USE_OPENSSL
# include <openssl/ssl.h>
# include <openssl/err.h>
#endif

#ifdef HAVE_SYS_FILIO_H
# include <sys/filio.h>
#endif

#include "sys-socket.h"

typedef struct {
	        PLUGIN_DATA;
} plugin_data;

static connection *connections_get_new_connection(server *srv) {
	connections *conns = srv->conns;
	size_t i;

	if (conns->size == 0) {
		conns->size = 128;
		conns->ptr = NULL;
		conns->ptr = malloc(sizeof(*conns->ptr) * conns->size);
		force_assert(NULL != conns->ptr);
		for (i = 0; i < conns->size; i++) {
			conns->ptr[i] = connection_init(srv);
		}
	} else if (conns->size == conns->used) {
		conns->size += 128;
		conns->ptr = realloc(conns->ptr, sizeof(*conns->ptr) * conns->size);
		force_assert(NULL != conns->ptr);

		for (i = conns->used; i < conns->size; i++) {
			conns->ptr[i] = connection_init(srv);
		}
	}

	connection_reset(srv, conns->ptr[conns->used]);
#if 0
	fprintf(stderr, "%s.%d: add: ", __FILE__, __LINE__);
	for (i = 0; i < conns->used + 1; i++) {
		fprintf(stderr, "%d ", conns->ptr[i]->fd);
	}
	fprintf(stderr, "\n");
#endif

	conns->ptr[conns->used]->ndx = conns->used;
	return conns->ptr[conns->used++];
}

static int connection_del(server *srv, connection *con) {
	size_t i;
	connections *conns = srv->conns;
	connection *temp;

	if (con == NULL) return -1;

	if (-1 == con->ndx) return -1;

	buffer_reset(con->uri.authority);
	buffer_reset(con->uri.path);
	buffer_reset(con->uri.query);
	buffer_reset(con->request.orig_uri);

	i = con->ndx;

	/* not last element */

	if (i != conns->used - 1) {
		temp = conns->ptr[i];
		conns->ptr[i] = conns->ptr[conns->used - 1];
		conns->ptr[conns->used - 1] = temp;

		conns->ptr[i]->ndx = i;
		conns->ptr[conns->used - 1]->ndx = -1;
	}

	conns->used--;

	con->ndx = -1;
#if 0
	fprintf(stderr, "%s.%d: del: (%d)", __FILE__, __LINE__, conns->used);
	for (i = 0; i < conns->used; i++) {
		fprintf(stderr, "%d ", conns->ptr[i]->fd);
	}
	fprintf(stderr, "\n");
#endif
	return 0;
}

int connection_close(server *srv, connection *con) {
#ifdef USE_OPENSSL
	server_socket *srv_sock = con->srv_socket;
#endif

#ifdef USE_OPENSSL
	if (srv_sock->is_ssl) {
		if (con->ssl) SSL_free(con->ssl);
		con->ssl = NULL;
	}
#endif

	fdevent_event_del(srv->ev, &(con->fde_ndx), con->fd);
	fdevent_unregister(srv->ev, con->fd);
#ifdef __WIN32
	if (closesocket(con->fd)) {
		log_error_write(srv, __FILE__, __LINE__, "sds",
				"(warning) close:", con->fd, strerror(errno));
	}
#else
	if (close(con->fd)) {
		log_error_write(srv, __FILE__, __LINE__, "sds",
				"(warning) close:", con->fd, strerror(errno));
	}
#endif

	srv->cur_fds--;
#if 0
	log_error_write(srv, __FILE__, __LINE__, "sd",
			"closed()", con->fd);
#endif

	connection_del(srv, con);
	connection_set_state(srv, con, CON_STATE_CONNECT);

	return 0;
}

#if 0
static void dump_packet(const unsigned char *data, size_t len) {
	size_t i, j;

	if (len == 0) return;

	for (i = 0; i < len; i++) {
		if (i % 16 == 0) fprintf(stderr, "  ");

		fprintf(stderr, "%02x ", data[i]);

		if ((i + 1) % 16 == 0) {
			fprintf(stderr, "  ");
			for (j = 0; j <= i % 16; j++) {
				unsigned char c;

				if (i-15+j >= len) break;

				c = data[i-15+j];

				fprintf(stderr, "%c", c > 32 && c < 128 ? c : '.');
			}

			fprintf(stderr, "\n");
		}
	}

	if (len % 16 != 0) {
		for (j = i % 16; j < 16; j++) {
			fprintf(stderr, "   ");
		}

		fprintf(stderr, "  ");
		for (j = i & ~0xf; j < len; j++) {
			unsigned char c;

			c = data[j];
			fprintf(stderr, "%c", c > 32 && c < 128 ? c : '.');
		}
		fprintf(stderr, "\n");
	}
}
#endif

static int connection_handle_read_ssl(server *srv, connection *con) {
#ifdef USE_OPENSSL
	int r, ssl_err, len, count = 0;
	char *mem = NULL;
	size_t mem_len = 0;

	if (!con->srv_socket->is_ssl) return -1;

	ERR_clear_error();
	do {
		chunkqueue_get_memory(con->read_queue, &mem, &mem_len, 0, SSL_pending(con->ssl));
#if 0
		/* overwrite everything with 0 */
		memset(mem, 0, mem_len);
#endif

		len = SSL_read(con->ssl, mem, mem_len);
		chunkqueue_use_memory(con->read_queue, len > 0 ? len : 0);

		if (con->renegotiations > 1 && con->conf.ssl_disable_client_renegotiation) {
			log_error_write(srv, __FILE__, __LINE__, "s", "SSL: renegotiation initiated by client, killing connection");
			connection_set_state(srv, con, CON_STATE_ERROR);
			return -1;
		}

		if (len > 0) {
			con->bytes_read += len;
			count += len;
		}
	} while (len == (ssize_t) mem_len && count < MAX_READ_LIMIT);


	if (len < 0) {
		int oerrno = errno;
		switch ((r = SSL_get_error(con->ssl, len))) {
		case SSL_ERROR_WANT_READ:
		case SSL_ERROR_WANT_WRITE:
			con->is_readable = 0;

			/* the manual says we have to call SSL_read with the same arguments next time.
			 * we ignore this restriction; no one has complained about it in 1.5 yet, so it probably works anyway.
			 */

			return 0;
		case SSL_ERROR_SYSCALL:
			/**
			 * man SSL_get_error()
			 *
			 * SSL_ERROR_SYSCALL
			 *   Some I/O error occurred.  The OpenSSL error queue may contain more
			 *   information on the error.  If the error queue is empty (i.e.
			 *   ERR_get_error() returns 0), ret can be used to find out more about
			 *   the error: If ret == 0, an EOF was observed that violates the
			 *   protocol.  If ret == -1, the underlying BIO reported an I/O error
			 *   (for socket I/O on Unix systems, consult errno for details).
			 *
			 */
			while((ssl_err = ERR_get_error())) {
				/* get all errors from the error-queue */
				log_error_write(srv, __FILE__, __LINE__, "sds", "SSL:",
						r, ERR_error_string(ssl_err, NULL));
			}

			switch(oerrno) {
			default:
				log_error_write(srv, __FILE__, __LINE__, "sddds", "SSL:",
						len, r, oerrno,
						strerror(oerrno));
				break;
			}

			break;
		case SSL_ERROR_ZERO_RETURN:
			/* clean shutdown on the remote side */

			if (r == 0) {
				/* FIXME: later */
			}

			/* fall thourgh */
		default:
			while((ssl_err = ERR_get_error())) {
				switch (ERR_GET_REASON(ssl_err)) {
				case SSL_R_SSL_HANDSHAKE_FAILURE:
				case SSL_R_TLSV1_ALERT_UNKNOWN_CA:
				case SSL_R_SSLV3_ALERT_CERTIFICATE_UNKNOWN:
				case SSL_R_SSLV3_ALERT_BAD_CERTIFICATE:
					if (!con->conf.log_ssl_noise) continue;
					break;
				default:
					break;
				}
				/* get all errors from the error-queue */
				log_error_write(srv, __FILE__, __LINE__, "sds", "SSL:",
				                r, ERR_error_string(ssl_err, NULL));
			}
			break;
		}

		connection_set_state(srv, con, CON_STATE_ERROR);

		return -1;
	} else if (len == 0) {
		con->is_readable = 0;
		/* the other end close the connection -> KEEP-ALIVE */

		return -2;
	} else {
		joblist_append(srv, con);
	}

	return 0;
#else
	UNUSED(srv);
	UNUSED(con);
	return -1;
#endif
}

/* 0: everything ok, -1: error, -2: con closed */
static int connection_handle_read(server *srv, connection *con) {
	int len;
	char *mem = NULL;
	size_t mem_len = 0;
	int toread;

	if (con->srv_socket->is_ssl) {
		return connection_handle_read_ssl(srv, con);
	}

	/* default size for chunks is 4kb; only use bigger chunks if FIONREAD tells
	 *  us more than 4kb is available
	 * if FIONREAD doesn't signal a big chunk we fill the previous buffer
	 *  if it has >= 1kb free
	 */
#if defined(__WIN32)
	chunkqueue_get_memory(con->read_queue, &mem, &mem_len, 0, 4096);

	len = recv(con->fd, mem, mem_len, 0);
#else /* __WIN32 */
	if (ioctl(con->fd, FIONREAD, &toread) || toread == 0 || toread <= 4*1024) {
		toread = 4096;
	}
	else if (toread > MAX_READ_LIMIT) {
		toread = MAX_READ_LIMIT;
	}
	chunkqueue_get_memory(con->read_queue, &mem, &mem_len, 0, toread);

	len = read(con->fd, mem, mem_len);
#endif /* __WIN32 */

	chunkqueue_use_memory(con->read_queue, len > 0 ? len : 0);

	if (len < 0) {
		con->is_readable = 0;

#if defined(__WIN32)
		{
			int lastError = WSAGetLastError();
			switch (lastError) {
			case EAGAIN:
				return 0;
			case EINTR:
				/* we have been interrupted before we could read */
				con->is_readable = 1;
				return 0;
			case ECONNRESET:
				/* suppress logging for this error, expected for keep-alive */
				break;
			default:
				log_error_write(srv, __FILE__, __LINE__, "sd", "connection closed - recv failed: ", lastError);
				break;
			}
		}
#else /* __WIN32 */
		switch (errno) {
		case EAGAIN:
			return 0;
		case EINTR:
			/* we have been interrupted before we could read */
			con->is_readable = 1;
			return 0;
		case ECONNRESET:
			/* suppress logging for this error, expected for keep-alive */
			break;
		default:
			log_error_write(srv, __FILE__, __LINE__, "ssd", "connection closed - read failed: ", strerror(errno), errno);
			break;
		}
#endif /* __WIN32 */

		connection_set_state(srv, con, CON_STATE_ERROR);

		return -1;
	} else if (len == 0) {
		con->is_readable = 0;
		/* the other end close the connection -> KEEP-ALIVE */

		/* pipelining */

		return -2;
	} else if (len != (ssize_t) mem_len) {
		/* we got less then expected, wait for the next fd-event */

		con->is_readable = 0;
	}

	con->bytes_read += len;
#if 0
	dump_packet(b->ptr, len);
#endif

	return 0;
}

static void connection_handle_errdoc_init(connection *con) {
	/* reset caching response headers potentially added by mod_expire */
	data_string *ds;
	if (NULL != (ds = (data_string*) array_get_element(con->response.headers, "Expires"))) {
		buffer_reset(ds->value); /* Headers with empty values are ignored for output */
	}
	if (NULL != (ds = (data_string*) array_get_element(con->response.headers, "Cache-Control"))) {
		buffer_reset(ds->value); /* Headers with empty values are ignored for output */
	}
}

static int connection_handle_write_prepare(server *srv, connection *con) {
	if (con->mode == DIRECT) {
		/* static files */
		switch(con->request.http_method) {
		case HTTP_METHOD_GET:
		case HTTP_METHOD_POST:
		case HTTP_METHOD_HEAD:
			break;
		case HTTP_METHOD_OPTIONS:
			/*
			 * 400 is coming from the request-parser BEFORE uri.path is set
			 * 403 is from the response handler when noone else catched it
			 *
			 * */
			if ((!con->http_status || con->http_status == 200) && !buffer_string_is_empty(con->uri.path) &&
			    con->uri.path->ptr[0] != '*') {
				response_header_insert(srv, con, CONST_STR_LEN("Allow"), CONST_STR_LEN("OPTIONS, GET, HEAD, POST"));

				con->response.transfer_encoding &= ~HTTP_TRANSFER_ENCODING_CHUNKED;
				con->parsed_response &= ~HTTP_CONTENT_LENGTH;

				con->http_status = 200;
				con->file_finished = 1;

				chunkqueue_reset(con->write_queue);
			}
			break;
		default:
			if (0 == con->http_status) {
				con->http_status = 501;
			}
			break;
		}
	}

	if (con->http_status == 0) {
		con->http_status = 403;
	}

	switch(con->http_status) {
	case 204: /* class: header only */
	case 205:
	case 304:
		/* disable chunked encoding again as we have no body */
		con->response.transfer_encoding &= ~HTTP_TRANSFER_ENCODING_CHUNKED;
		con->parsed_response &= ~HTTP_CONTENT_LENGTH;
		chunkqueue_reset(con->write_queue);

		con->file_finished = 1;
		break;
	default: /* class: header + body */
		if (con->mode != DIRECT) break;

		/* only custom body for 4xx and 5xx */
		if (con->http_status < 400 || con->http_status >= 600) break;

		con->file_finished = 0;

		buffer_reset(con->physical.path);
		connection_handle_errdoc_init(con);

		/* try to send static errorfile */
		if (!buffer_string_is_empty(con->conf.errorfile_prefix)) {
			stat_cache_entry *sce = NULL;

			buffer_copy_buffer(con->physical.path, con->conf.errorfile_prefix);
			buffer_append_int(con->physical.path, con->http_status);
			buffer_append_string_len(con->physical.path, CONST_STR_LEN(".html"));

			if (0 == http_chunk_append_file(srv, con, con->physical.path)) {
				con->file_finished = 1;
				if (HANDLER_ERROR != stat_cache_get_entry(srv, con, con->physical.path, &sce)) {
					response_header_overwrite(srv, con, CONST_STR_LEN("Content-Type"), CONST_BUF_LEN(sce->content_type));
				}
			}
		}

		if (!con->file_finished) {
			buffer *b;

			buffer_reset(con->physical.path);

			con->file_finished = 1;
			b = buffer_init();

			/* build default error-page */
			buffer_copy_string_len(b, CONST_STR_LEN(
					   "<?xml version=\"1.0\" encoding=\"iso-8859-1\"?>\n"
					   "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\n"
					   "         \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n"
					   "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" lang=\"en\">\n"
					   " <head>\n"
					   "  <title>"));
			buffer_append_int(b, con->http_status);
			buffer_append_string_len(b, CONST_STR_LEN(" - "));
			buffer_append_string(b, get_http_status_name(con->http_status));

			buffer_append_string_len(b, CONST_STR_LEN(
					     "</title>\n"
					     " </head>\n"
					     " <body>\n"
					     "  <h1>"));
			buffer_append_int(b, con->http_status);
			buffer_append_string_len(b, CONST_STR_LEN(" - "));
			buffer_append_string(b, get_http_status_name(con->http_status));

			buffer_append_string_len(b, CONST_STR_LEN("</h1>\n"
					     " </body>\n"
					     "</html>\n"
					     ));

			http_chunk_append_buffer(srv, con, b);
			buffer_free(b);
			http_chunk_close(srv, con);

			response_header_overwrite(srv, con, CONST_STR_LEN("Content-Type"), CONST_STR_LEN("text/html"));
		}
		break;
	}

	if (con->file_finished) {
		/* we have all the content and chunked encoding is not used, set a content-length */

		if ((!(con->parsed_response & HTTP_CONTENT_LENGTH)) &&
		    (con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) == 0) {
			off_t qlen = chunkqueue_length(con->write_queue);

			/**
			 * The Content-Length header only can be sent if we have content:
			 * - HEAD doesn't have a content-body (but have a content-length)
			 * - 1xx, 204 and 304 don't have a content-body (RFC 2616 Section 4.3)
			 *
			 * Otherwise generate a Content-Length header as chunked encoding is not 
			 * available
			 */
			if ((con->http_status >= 100 && con->http_status < 200) ||
			    con->http_status == 204 ||
			    con->http_status == 304) {
				data_string *ds;
				/* no Content-Body, no Content-Length */
				if (NULL != (ds = (data_string*) array_get_element(con->response.headers, "Content-Length"))) {
					buffer_reset(ds->value); /* Headers with empty values are ignored for output */
				}
			} else if (qlen > 0 || con->request.http_method != HTTP_METHOD_HEAD) {
				/* qlen = 0 is important for Redirects (301, ...) as they MAY have
				 * a content. Browsers are waiting for a Content otherwise
				 */
				buffer_copy_int(srv->tmp_buf, qlen);

				response_header_overwrite(srv, con, CONST_STR_LEN("Content-Length"), CONST_BUF_LEN(srv->tmp_buf));
			}
		}
	} else {
		/**
		 * the file isn't finished yet, but we have all headers
		 *
		 * to get keep-alive we either need:
		 * - Content-Length: ... (HTTP/1.0 and HTTP/1.0) or
		 * - Transfer-Encoding: chunked (HTTP/1.1)
		 */

		if (((con->parsed_response & HTTP_CONTENT_LENGTH) == 0) &&
		    ((con->response.transfer_encoding & HTTP_TRANSFER_ENCODING_CHUNKED) == 0)) {
			con->keep_alive = 0;
		}

		/**
		 * if the backend sent a Connection: close, follow the wish
		 *
		 * NOTE: if the backend sent Connection: Keep-Alive, but no Content-Length, we
		 * will close the connection. That's fine. We can always decide the close 
		 * the connection
		 *
		 * FIXME: to be nice we should remove the Connection: ... 
		 */
		if (con->parsed_response & HTTP_CONNECTION) {
			/* a subrequest disable keep-alive although the client wanted it */
			if (con->keep_alive && !con->response.keep_alive) {
				con->keep_alive = 0;
			}
		}
	}

	if (con->request.http_method == HTTP_METHOD_HEAD) {
		/**
		 * a HEAD request has the same as a GET 
		 * without the content
		 */