git.meshlink.io Git - meshlink/blob - src/meta.c

   1 /*
   2     meta.c -- handle the meta communication
   3     Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>,
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License along
  16     with this program; if not, write to the Free Software Foundation, Inc.,
  17     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "system.h"
  21
  22 #include "connection.h"
  23 #include "logger.h"
  24 #include "meshlink_internal.h"
  25 #include "meta.h"
  26 #include "net.h"
  27 #include "protocol.h"
  28 #include "utils.h"
  29 #include "xalloc.h"
  30
  31 bool send_meta_sptps(void *handle, uint8_t type, const void *buffer, size_t length) {
  32         connection_t *c = handle;
  33         meshlink_handle_t *mesh = c->mesh;
  34
  35         if(!c) {
  36                 logger(DEBUG_ALWAYS, LOG_ERR, "send_meta_sptps() called with NULL pointer!");
  37                 abort();
  38         }
  39
  40         buffer_add(&c->outbuf, (const char *)buffer, length);
  41         io_set(&mesh->loop, &c->io, IO_READ | IO_WRITE);
  42
  43         return true;
  44 }
  45
  46 bool send_meta(meshlink_handle_t *mesh, connection_t *c, const char *buffer, int length) {
  47         if(!c) {
  48                 logger(DEBUG_ALWAYS, LOG_ERR, "send_meta() called with NULL pointer!");
  49                 abort();
  50         }
  51
  52         logger(DEBUG_META, LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length,
  53                            c->name, c->hostname);
  54
  55         if(c->allow_request == ID) {
  56                 buffer_add(&c->outbuf, buffer, length);
  57                 io_set(&mesh->loop, &c->io, IO_READ | IO_WRITE);
  58                 return true;
  59         }
  60
  61         return sptps_send_record(&c->sptps, 0, buffer, length);
  62 }
  63
  64 void broadcast_meta(meshlink_handle_t *mesh, connection_t *from, const char *buffer, int length) {
  65         for list_each(connection_t, c, mesh->connections)
  66                 if(c != from && c->status.active)
  67                         send_meta(mesh, c, buffer, length);
  68 }
  69
  70 bool receive_meta_sptps(void *handle, uint8_t type, const void *data, uint16_t length) {
  71         connection_t *c = handle;
  72         meshlink_handle_t *mesh = c->mesh;
  73         char *request = (char *)data;
  74
  75         if(!c) {
  76                 logger(DEBUG_ALWAYS, LOG_ERR, "receive_meta_sptps() called with NULL pointer!");
  77                 abort();
  78         }
  79
  80         if(type == SPTPS_HANDSHAKE) {
  81                 if(c->allow_request == ACK)
  82                         return send_ack(mesh, c);
  83                 else
  84                         return true;
  85         }
  86
  87         if(!request)
  88                 return true;
  89
  90         /* Are we receiving a TCPpacket? */
  91
  92         if(c->tcplen) {
  93                 if(length != c->tcplen)
  94                         return false;
  95                 receive_tcppacket(mesh, c, request, length);
  96                 c->tcplen = 0;
  97                 return true;
  98         }
  99
 100         /* Change newline to null byte, just like non-SPTPS requests */
 101
 102         if(request[length - 1] == '\n')
 103                 request[length - 1] = 0;
 104
 105         /* Otherwise we are waiting for a request */
 106
 107         return receive_request(mesh, c, request);
 108 }
 109
 110 bool receive_meta(meshlink_handle_t *mesh, connection_t *c) {
 111         int inlen;
 112         char inbuf[MAXBUFSIZE];
 113         char *bufp = inbuf, *endp;
 114
 115         /* Strategy:
 116            - Read as much as possible from the TCP socket in one go.
 117            - Decrypt it.
 118            - Check if a full request is in the input buffer.
 119            - If yes, process request and remove it from the buffer,
 120            then check again.
 121            - If not, keep stuff in buffer and exit.
 122          */
 123
 124         buffer_compact(&c->inbuf, MAXBUFSIZE);
 125
 126         if(sizeof inbuf <= c->inbuf.len) {
 127                 logger(DEBUG_ALWAYS, LOG_ERR, "Input buffer full for %s (%s)", c->name, c->hostname);
 128                 return false;
 129         }
 130
 131         inlen = recv(c->socket, inbuf, sizeof inbuf - c->inbuf.len, 0);
 132
 133         if(inlen <= 0) {
 134                 if(!inlen || !errno) {
 135                         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection closed by %s (%s)",
 136                                            c->name, c->hostname);
 137                 } else if(sockwouldblock(sockerrno))
 138                         return true;
 139                 else
 140                         logger(DEBUG_ALWAYS, LOG_ERR, "Metadata socket read error for %s (%s): %s",
 141                                    c->name, c->hostname, sockstrerror(sockerrno));
 142                 return false;
 143         }
 144
 145         if(c->allow_request == ID) {
 146                 endp = memchr(bufp, '\n', inlen);
 147                 if(endp)
 148                         endp++;
 149                 else
 150                         endp = bufp + inlen;
 151
 152                 buffer_add(&c->inbuf, bufp, endp - bufp);
 153
 154                 inlen -= endp - bufp;
 155                 bufp = endp;
 156
 157                 while(c->inbuf.len) {
 158                         char *request = buffer_readline(&c->inbuf);
 159                         if(request) {
 160                                 bool result = receive_request(mesh, c, request);
 161                                 if(!result)
 162                                         return false;
 163                                 continue;
 164                         } else {
 165                                 break;
 166                         }
 167                 }
 168
 169                 return true;
 170         }
 171
 172         return sptps_receive_data(&c->sptps, bufp, inlen);
 173 }