/*
meta.c -- handle the meta communication
- Copyright (C) 2000-2002 Guus Sliepen <guus@sliepen.warande.net>,
- 2000-2002 Ivo Timmermans <itimmermans@bigfoot.com>
+ Copyright (C) 2000-2014 Guus Sliepen <guus@tinc-vpn.org>,
+ 2000-2005 Ivo Timmermans
+ 2006 Scott Lamb <slamb@slamb.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id: meta.c,v 1.1.2.25 2002/03/01 14:09:31 guus Exp $
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#include "config.h"
-#include <utils.h>
-#include <avl_tree.h>
-
-#include <errno.h>
-#include <syslog.h>
-#include <unistd.h>
-#include <string.h>
-/* This line must be below the rest for FreeBSD */
-#include <sys/types.h>
-#include <sys/socket.h>
-
-#include <openssl/evp.h>
+#include "system.h"
-#include "net.h"
+#include "cipher.h"
#include "connection.h"
-#include "system.h"
+#include "logger.h"
+#include "meta.h"
+#include "net.h"
#include "protocol.h"
+#include "utils.h"
+#include "xalloc.h"
+
+#ifndef MIN
+#define MIN(x, y) (((x)<(y))?(x):(y))
+#endif
-int send_meta(connection_t *c, char *buffer, int length)
-{
- char *bufp;
- int outlen;
- char outbuf[MAXBUFSIZE];
-cp
- if(debug_lvl >= DEBUG_META)
- syslog(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s)"), length,
- c->name, c->hostname);
-
- if(c->status.encryptout)
- {
- EVP_EncryptUpdate(c->outctx, outbuf, &outlen, buffer, length);
- bufp = outbuf;
- length = outlen;
- }
- else
- bufp = buffer;
-
- if(write(c->socket, bufp, length) < 0)
- {
- syslog(LOG_ERR, _("Sending meta data to %s (%s) failed: %s"), c->name, c->hostname, strerror(errno));
- return -1;
- }
-cp
- return 0;
+bool send_meta_sptps(void *handle, uint8_t type, const void *buffer, size_t length) {
+ connection_t *c = handle;
+
+ if(!c) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "send_meta_sptps() called with NULL pointer!");
+ abort();
+ }
+
+ buffer_add(&c->outbuf, buffer, length);
+ io_set(&c->io, IO_READ | IO_WRITE);
+
+ return true;
}
-void broadcast_meta(connection_t *from, char *buffer, int length)
-{
- avl_node_t *node;
- connection_t *c;
-cp
- for(node = connection_tree->head; node; node = node->next)
- {
- c = (connection_t *)node->data;
- if(c != from && c->status.active)
- send_meta(c, buffer, length);
- }
-cp
+bool send_meta(connection_t *c, const char *buffer, int length) {
+ if(!c) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "send_meta() called with NULL pointer!");
+ abort();
+ }
+
+ logger(DEBUG_META, LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length,
+ c->name, c->hostname);
+
+ if(c->protocol_minor >= 2)
+ return sptps_send_record(&c->sptps, 0, buffer, length);
+
+ /* Add our data to buffer */
+ if(c->status.encryptout) {
+#ifdef DISABLE_LEGACY
+ return false;
+#else
+ size_t outlen = length;
+
+ if(!cipher_encrypt(c->outcipher, buffer, length, buffer_prepare(&c->outbuf, length), &outlen, false) || outlen != length) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting metadata to %s (%s)",
+ c->name, c->hostname);
+ return false;
+ }
+#endif
+ } else {
+ buffer_add(&c->outbuf, buffer, length);
+ }
+
+ io_set(&c->io, IO_READ | IO_WRITE);
+
+ return true;
+}
+
+void send_meta_raw(connection_t *c, const char *buffer, int length) {
+ if(!c) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "send_meta() called with NULL pointer!");
+ abort();
+ }
+
+ logger(DEBUG_META, LOG_DEBUG, "Sending %d bytes of raw metadata to %s (%s)", length,
+ c->name, c->hostname);
+
+ buffer_add(&c->outbuf, buffer, length);
+
+ io_set(&c->io, IO_READ | IO_WRITE);
+}
+
+void broadcast_meta(connection_t *from, const char *buffer, int length) {
+ for list_each(connection_t, c, connection_list)
+ if(c != from && c->edge)
+ send_meta(c, buffer, length);
+}
+
+bool receive_meta_sptps(void *handle, uint8_t type, const void *vdata, uint16_t length) {
+ const char *data = vdata;
+ connection_t *c = handle;
+
+ if(!c) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "receive_meta_sptps() called with NULL pointer!");
+ abort();
+ }
+
+ if(type == SPTPS_HANDSHAKE) {
+ if(c->allow_request == ACK)
+ return send_ack(c);
+ else
+ return true;
+ }
+
+ if(!data)
+ return true;
+
+ /* Are we receiving a TCPpacket? */
+
+ if(c->tcplen) {
+ if(length != c->tcplen)
+ return false;
+ receive_tcppacket(c, data, length);
+ c->tcplen = 0;
+ return true;
+ }
+
+ /* Change newline to null byte, just like non-SPTPS requests */
+
+ if(data[length - 1] == '\n')
+ ((char *)data)[length - 1] = 0;
+
+ /* Otherwise we are waiting for a request */
+
+ return receive_request(c, data);
}
-int receive_meta(connection_t *c)
-{
- int x, l = sizeof(x);
- int oldlen, i;
- int lenin, reqlen;
- int decrypted = 0;
- char inbuf[MAXBUFSIZE];
-cp
- if(getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0)
- {
- syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%s %s (%s)"), __FILE__, __LINE__, c->socket, strerror(errno),
- c->name, c->hostname);
- return -1;
- }
- if(x)
- {
- syslog(LOG_ERR, _("Metadata socket error for %s (%s): %s"),
- c->name, c->hostname, strerror(x));
- return -1;
- }
-
- /* Strategy:
- - Read as much as possible from the TCP socket in one go.
- - Decrypt it.
- - Check if a full request is in the input buffer.
- - If yes, process request and remove it from the buffer,
- then check again.
- - If not, keep stuff in buffer and exit.
- */
-
- lenin = read(c->socket, c->buffer + c->buflen, MAXBUFSIZE - c->buflen);
-
- if(lenin<=0)
- {
- if(lenin==0)
- {
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Connection closed by %s (%s)"),
- c->name, c->hostname);
- }
- else
- if(errno==EINTR)
- return 0;
- else
- syslog(LOG_ERR, _("Metadata socket read error for %s (%s): %s"),
- c->name, c->hostname, strerror(errno));
-
- return -1;
- }
-
- oldlen = c->buflen;
- c->buflen += lenin;
-
- while(lenin)
- {
- /* Decrypt */
-
- if(c->status.decryptin && !decrypted)
- {
- EVP_DecryptUpdate(c->inctx, inbuf, &lenin, c->buffer + oldlen, lenin);
- memcpy(c->buffer + oldlen, inbuf, lenin);
- decrypted = 1;
- }
-
- /* Are we receiving a TCPpacket? */
-
- if(c->tcplen)
- {
- if(c->tcplen <= c->buflen)
- {
- receive_tcppacket(c, c->buffer, c->tcplen);
-
- c->buflen -= c->tcplen;
- lenin -= c->tcplen;
- memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
- oldlen = 0;
- c->tcplen = 0;
- continue;
- }
- else
- {
- break;
- }
- }
-
- /* Otherwise we are waiting for a request */
-
- reqlen = 0;
-
- for(i = oldlen; i < c->buflen; i++)
- {
- if(c->buffer[i] == '\n')
- {
- c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
- reqlen = i + 1;
- break;
- }
- }
-
- if(reqlen)
- {
- if(receive_request(c))
- return -1;
-
- c->buflen -= reqlen;
- lenin -= reqlen;
- memmove(c->buffer, c->buffer + reqlen, c->buflen);
- oldlen = 0;
- continue;
- }
- else
- {
- break;
- }
- }
-
- if(c->buflen >= MAXBUFSIZE)
- {
- syslog(LOG_ERR, _("Metadata read buffer overflow for %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- c->last_ping_time = now;
-cp
- return 0;
+bool receive_meta(connection_t *c) {
+ int inlen;
+ char inbuf[MAXBUFSIZE];
+ char *bufp = inbuf, *endp;
+
+ /* Strategy:
+ - Read as much as possible from the TCP socket in one go.
+ - Decrypt it.
+ - Check if a full request is in the input buffer.
+ - If yes, process request and remove it from the buffer,
+ then check again.
+ - If not, keep stuff in buffer and exit.
+ */
+
+ buffer_compact(&c->inbuf, MAXBUFSIZE);
+
+ if(sizeof inbuf <= c->inbuf.len) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Input buffer full for %s (%s)", c->name, c->hostname);
+ return false;
+ }
+
+ inlen = recv(c->socket, inbuf, sizeof inbuf - c->inbuf.len, 0);
+
+ if(inlen <= 0) {
+ if(!inlen || !sockerrno) {
+ logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection closed by %s (%s)",
+ c->name, c->hostname);
+ } else if(sockwouldblock(sockerrno))
+ return true;
+ else
+ logger(DEBUG_ALWAYS, LOG_ERR, "Metadata socket read error for %s (%s): %s",
+ c->name, c->hostname, sockstrerror(sockerrno));
+ return false;
+ }
+
+ do {
+ /* Are we receiving a SPTPS packet? */
+
+ if(c->sptpslen) {
+ int len = MIN(inlen, c->sptpslen - c->inbuf.len);
+ buffer_add(&c->inbuf, bufp, len);
+
+ char *sptpspacket = buffer_read(&c->inbuf, c->sptpslen);
+ if(!sptpspacket)
+ return true;
+
+ if(!receive_tcppacket_sptps(c, sptpspacket, c->sptpslen))
+ return false;
+ c->sptpslen = 0;
+
+ bufp += len;
+ inlen -= len;
+ continue;
+ }
+
+ if(c->protocol_minor >= 2) {
+ int len = sptps_receive_data(&c->sptps, bufp, inlen);
+ if(!len)
+ return false;
+ bufp += len;
+ inlen -= len;
+ continue;
+ }
+
+ if(!c->status.decryptin) {
+ endp = memchr(bufp, '\n', inlen);
+ if(endp)
+ endp++;
+ else
+ endp = bufp + inlen;
+
+ buffer_add(&c->inbuf, bufp, endp - bufp);
+
+ inlen -= endp - bufp;
+ bufp = endp;
+ } else {
+#ifdef DISABLE_LEGACY
+ return false;
+#else
+ size_t outlen = inlen;
+
+ if(!cipher_decrypt(c->incipher, bufp, inlen, buffer_prepare(&c->inbuf, inlen), &outlen, false) || inlen != outlen) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting metadata from %s (%s)",
+ c->name, c->hostname);
+ return false;
+ }
+
+ inlen = 0;
+#endif
+ }
+
+ while(c->inbuf.len) {
+ /* Are we receiving a TCPpacket? */
+
+ if(c->tcplen) {
+ char *tcpbuffer = buffer_read(&c->inbuf, c->tcplen);
+ if(!tcpbuffer)
+ break;
+
+ if(!c->node) {
+ if(c->outgoing && proxytype == PROXY_SOCKS4 && c->allow_request == ID) {
+ if(tcpbuffer[0] == 0 && tcpbuffer[1] == 0x5a) {
+ logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Proxy request granted");
+ } else {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Proxy request rejected");
+ return false;
+ }
+ } else if(c->outgoing && proxytype == PROXY_SOCKS5 && c->allow_request == ID) {
+ if(tcpbuffer[0] != 5) {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Invalid response from proxy server");
+ return false;
+ }
+ if(tcpbuffer[1] == (char)0xff) {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Proxy request rejected: unsuitable authentication method");
+ return false;
+ }
+ if(tcpbuffer[2] != 5) {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Invalid response from proxy server");
+ return false;
+ }
+ if(tcpbuffer[3] == 0) {
+ logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Proxy request granted");
+ } else {
+ logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Proxy request rejected");
+ return false;
+ }
+ } else {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "c->tcplen set but c->node is NULL!");
+ abort();
+ }
+ } else {
+ if(c->allow_request == ALL) {
+ receive_tcppacket(c, tcpbuffer, c->tcplen);
+ } else {
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname);
+ return false;
+ }
+ }
+
+ c->tcplen = 0;
+ }
+
+ /* Otherwise we are waiting for a request */
+
+ char *request = buffer_readline(&c->inbuf);
+ if(request) {
+ bool result = receive_request(c, request);
+ if(!result)
+ return false;
+ continue;
+ } else {
+ break;
+ }
+ }
+ } while(inlen);
+
+ return true;
}