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 char *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, 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 char *data, uint16_t length) {
  71         connection_t *c = handle;
  72         meshlink_handle_t *mesh = c->mesh;
  73
  74         if(!c) {
  75                 logger(DEBUG_ALWAYS, LOG_ERR, "receive_meta_sptps() called with NULL pointer!");
  76                 abort();
  77         }
  78
  79         if(type == SPTPS_HANDSHAKE) {
  80                 if(c->allow_request == ACK)
  81                         return send_ack(mesh, c);
  82                 else
  83                         return true;
  84         }
  85
  86         if(!data)
  87                 return true;
  88
  89         /* Are we receiving a TCPpacket? */
  90
  91         if(c->tcplen) {
  92                 if(length != c->tcplen)
  93                         return false;
  94                 receive_tcppacket(mesh, c, data, length);
  95                 c->tcplen = 0;
  96                 return true;
  97         }
  98
  99         /* Change newline to null byte, just like non-SPTPS requests */
 100
 101         if(data[length - 1] == '\n')
 102                 ((char *)data)[length - 1] = 0;
 103
 104         /* Otherwise we are waiting for a request */
 105
 106         return receive_request(mesh, c, data);
 107 }
 108
 109 bool receive_meta(meshlink_handle_t *mesh, connection_t *c) {
 110         int inlen;
 111         char inbuf[MAXBUFSIZE];
 112         char *bufp = inbuf, *endp;
 113
 114         /* Strategy:
 115            - Read as much as possible from the TCP socket in one go.
 116            - Decrypt it.
 117            - Check if a full request is in the input buffer.
 118            - If yes, process request and remove it from the buffer,
 119            then check again.
 120            - If not, keep stuff in buffer and exit.
 121          */
 122
 123         buffer_compact(&c->inbuf, MAXBUFSIZE);
 124
 125         if(sizeof inbuf <= c->inbuf.len) {
 126                 logger(DEBUG_ALWAYS, LOG_ERR, "Input buffer full for %s (%s)", c->name, c->hostname);
 127                 return false;
 128         }
 129
 130         inlen = recv(c->socket, inbuf, sizeof inbuf - c->inbuf.len, 0);
 131
 132         if(inlen <= 0) {
 133                 if(!inlen || !errno) {
 134                         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection closed by %s (%s)",
 135                                            c->name, c->hostname);
 136                 } else if(sockwouldblock(sockerrno))
 137                         return true;
 138                 else
 139                         logger(DEBUG_ALWAYS, LOG_ERR, "Metadata socket read error for %s (%s): %s",
 140                                    c->name, c->hostname, sockstrerror(sockerrno));
 141                 return false;
 142         }
 143
 144         if(c->allow_request == ID) {
 145                 endp = memchr(bufp, '\n', inlen);
 146                 if(endp)
 147                         endp++;
 148                 else
 149                         endp = bufp + inlen;
 150
 151                 buffer_add(&c->inbuf, bufp, endp - bufp);
 152
 153                 inlen -= endp - bufp;
 154                 bufp = endp;
 155
 156                 while(c->inbuf.len) {
 157                         char *request = buffer_readline(&c->inbuf);
 158                         if(request) {
 159                                 bool result = receive_request(mesh, c, request);
 160                                 if(!result)
 161                                         return false;
 162                                 continue;
 163                         } else {
 164                                 break;
 165                         }
 166                 }
 167
 168                 return true;
 169         }
 170
 171         return sptps_receive_data(&c->sptps, bufp, inlen);
 172 }