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

   1 /*
   2     protocol_edge.c -- handle the meta-protocol, edges
   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 "conf.h"
  23 #include "connection.h"
  24 #include "edge.h"
  25 #include "graph.h"
  26 #include "logger.h"
  27 #include "meshlink_internal.h"
  28 #include "meta.h"
  29 #include "net.h"
  30 #include "netutl.h"
  31 #include "node.h"
  32 #include "protocol.h"
  33 #include "utils.h"
  34 #include "xalloc.h"
  35 #include "submesh.h"
  36
  37 bool send_add_edge(meshlink_handle_t *mesh, connection_t *c, const edge_t *e, int contradictions) {
  38         bool x;
  39         char *address, *port;
  40         char *from_submesh, *to_submesh;
  41         submesh_t *s = NULL;
  42
  43         if(c->node && c->node->submesh) {
  44                 if(!submesh_allows_node(e->from->submesh, c->node)) {
  45                         return true;
  46                 }
  47
  48                 if(!submesh_allows_node(e->to->submesh, c->node)) {
  49                         return true;
  50                 }
  51         }
  52
  53         if(e->from->submesh && e->to->submesh && (e->from->submesh != e->to->submesh)) {
  54                 return true;
  55         }
  56
  57         sockaddr2str(&e->address, &address, &port);
  58
  59         if(e->from->submesh) {
  60                 from_submesh = e->from->submesh->name;
  61         } else {
  62                 from_submesh = CORE_MESH;
  63         }
  64
  65         if(e->to->submesh) {
  66                 to_submesh = e->to->submesh->name;
  67         } else {
  68                 to_submesh = CORE_MESH;
  69         }
  70
  71         if(e->from->submesh) {
  72                 s = e->from->submesh;
  73         } else {
  74                 s = e->to->submesh;
  75         }
  76
  77         x = send_request(mesh, c, s, "%d %x %s %d %s %s %s %s %d %s %x %d %d %x", ADD_EDGE, prng(mesh, UINT_MAX),
  78                          e->from->name, e->from->devclass, from_submesh, e->to->name, address, port,
  79                          e->to->devclass, to_submesh, OPTION_PMTU_DISCOVERY, e->weight, contradictions, e->from->session_id);
  80         free(address);
  81         free(port);
  82
  83         return x;
  84 }
  85
  86 bool add_edge_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
  87         assert(request);
  88         assert(*request);
  89
  90         edge_t *e;
  91         node_t *from, *to;
  92         char from_name[MAX_STRING_SIZE];
  93         int from_devclass;
  94         char from_submesh_name[MAX_STRING_SIZE] = "";
  95         char to_name[MAX_STRING_SIZE];
  96         char to_address[MAX_STRING_SIZE];
  97         char to_port[MAX_STRING_SIZE];
  98         int to_devclass;
  99         char to_submesh_name[MAX_STRING_SIZE] = "";
 100         sockaddr_t address;
 101         int weight;
 102         int contradictions = 0;
 103         uint32_t session_id = 0;
 104         submesh_t *s = NULL;
 105
 106         if(sscanf(request, "%*d %*x "MAX_STRING" %d "MAX_STRING" "MAX_STRING" "MAX_STRING" "MAX_STRING" %d "MAX_STRING" %*x %d %d %x",
 107                         from_name, &from_devclass, from_submesh_name, to_name, to_address, to_port, &to_devclass, to_submesh_name,
 108                         &weight, &contradictions, &session_id) < 9) {
 109                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s", "ADD_EDGE", c->name);
 110                 return false;
 111         }
 112
 113         // Check if devclasses are valid
 114
 115         if(from_devclass < 0 || from_devclass >= DEV_CLASS_COUNT) {
 116                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ADD_EDGE", c->name, "from devclass invalid");
 117                 return false;
 118         }
 119
 120         if(to_devclass < 0 || to_devclass >= DEV_CLASS_COUNT) {
 121                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ADD_EDGE", c->name, "to devclass invalid");
 122                 return false;
 123         }
 124
 125         if(0 == strcmp(from_submesh_name, "")) {
 126                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ADD_EDGE", c->name, "invalid submesh id");
 127                 return false;
 128         }
 129
 130         if(0 == strcmp(to_submesh_name, "")) {
 131                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ADD_EDGE", c->name, "invalid submesh id");
 132                 return false;
 133         }
 134
 135         if(seen_request(mesh, request)) {
 136                 return true;
 137         }
 138
 139         /* Lookup nodes */
 140
 141         from = lookup_node(mesh, from_name);
 142         to = lookup_node(mesh, to_name);
 143
 144         if(!from) {
 145                 from = new_node();
 146                 from->status.dirty = true;
 147                 from->status.blacklisted = mesh->default_blacklist;
 148                 from->name = xstrdup(from_name);
 149                 from->devclass = from_devclass;
 150
 151                 from->submesh = NULL;
 152
 153                 if(0 != strcmp(from_submesh_name, CORE_MESH)) {
 154                         if(!(from->submesh = lookup_or_create_submesh(mesh, from_submesh_name))) {
 155                                 return false;
 156                         }
 157                 }
 158
 159                 node_add(mesh, from);
 160         }
 161
 162         if(contradictions > 50) {
 163                 handle_duplicate_node(mesh, from);
 164         }
 165
 166         from->devclass = from_devclass;
 167
 168         if(!from->session_id) {
 169                 from->session_id = session_id;
 170         }
 171
 172         if(!to) {
 173                 to = new_node();
 174                 to->status.dirty = true;
 175                 to->status.blacklisted = mesh->default_blacklist;
 176                 to->name = xstrdup(to_name);
 177                 to->devclass = to_devclass;
 178
 179                 to->submesh = NULL;
 180
 181                 if(0 != strcmp(to_submesh_name, CORE_MESH)) {
 182                         if(!(to->submesh = lookup_or_create_submesh(mesh, to_submesh_name))) {
 183                                 return false;
 184
 185                         }
 186                 }
 187
 188                 node_add(mesh, to);
 189         }
 190
 191         to->devclass = to_devclass;
 192
 193         /* Convert addresses */
 194
 195         address = str2sockaddr(to_address, to_port);
 196
 197         /* Check if edge already exists */
 198
 199         e = lookup_edge(from, to);
 200
 201         if(e) {
 202                 if(e->weight != weight || e->session_id != session_id || sockaddrcmp(&e->address, &address)) {
 203                         if(from == mesh->self) {
 204                                 logger(mesh, MESHLINK_WARNING, "Got %s from %s for ourself which does not match existing entry",
 205                                        "ADD_EDGE", c->name);
 206                                 send_add_edge(mesh, c, e, 0);
 207                                 return true;
 208                         } else {
 209                                 logger(mesh, MESHLINK_WARNING, "Got %s from %s which does not match existing entry",
 210                                        "ADD_EDGE", c->name);
 211                                 edge_del(mesh, e);
 212                         }
 213                 } else {
 214                         return true;
 215                 }
 216         } else if(from == mesh->self) {
 217                 logger(mesh, MESHLINK_WARNING, "Got %s from %s for ourself which does not exist",
 218                        "ADD_EDGE", c->name);
 219                 mesh->contradicting_add_edge++;
 220                 e = new_edge();
 221                 e->from = from;
 222                 e->to = to;
 223                 e->session_id = session_id;
 224                 send_del_edge(mesh, c, e, mesh->contradicting_add_edge);
 225                 free_edge(e);
 226                 return true;
 227         }
 228
 229         e = new_edge();
 230         e->from = from;
 231         e->to = to;
 232         e->address = address;
 233         e->weight = weight;
 234         e->session_id = session_id;
 235         edge_add(mesh, e);
 236
 237         /* Run MST before or after we tell the rest? */
 238
 239         graph(mesh);
 240
 241         if(e->from->submesh && e->to->submesh && (e->from->submesh != e->to->submesh)) {
 242                 logger(mesh, MESHLINK_ERROR, "Dropping add edge ( %s to %s )", e->from->submesh->name, e->to->submesh->name);
 243                 return false;
 244         }
 245
 246         if(e->from->submesh) {
 247                 s = e->from->submesh;
 248         } else {
 249                 s = e->to->submesh;
 250         }
 251
 252         /* Tell the rest about the new edge */
 253
 254         forward_request(mesh, c, s, request);
 255
 256         return true;
 257 }
 258
 259 bool send_del_edge(meshlink_handle_t *mesh, connection_t *c, const edge_t *e, int contradictions) {
 260         submesh_t *s = NULL;
 261
 262         if(c->node && c->node->submesh) {
 263                 if(!submesh_allows_node(e->from->submesh, c->node)) {
 264                         return true;
 265                 }
 266
 267                 if(!submesh_allows_node(e->to->submesh, c->node)) {
 268                         return true;
 269                 }
 270         }
 271
 272         if(e->from->submesh && e->to->submesh && (e->from->submesh != e->to->submesh)) {
 273                 return true;
 274         }
 275
 276
 277         if(e->from->submesh) {
 278                 s = e->from->submesh;
 279         } else {
 280                 s = e->to->submesh;
 281         }
 282
 283         return send_request(mesh, c, s, "%d %x %s %s %d %x", DEL_EDGE, prng(mesh, UINT_MAX),
 284                             e->from->name, e->to->name, contradictions, e->session_id);
 285 }
 286
 287 bool del_edge_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
 288         assert(request);
 289         assert(*request);
 290
 291         edge_t *e;
 292         char from_name[MAX_STRING_SIZE];
 293         char to_name[MAX_STRING_SIZE];
 294         node_t *from, *to;
 295         int contradictions = 0;
 296         uint32_t session_id = 0;
 297         submesh_t *s = NULL;
 298
 299         if(sscanf(request, "%*d %*x "MAX_STRING" "MAX_STRING" %d %x", from_name, to_name, &contradictions, &session_id) < 2) {
 300                 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s", "DEL_EDGE", c->name);
 301                 return false;
 302         }
 303
 304         if(seen_request(mesh, request)) {
 305                 return true;
 306         }
 307
 308         /* Lookup nodes */
 309
 310         from = lookup_node(mesh, from_name);
 311         to = lookup_node(mesh, to_name);
 312
 313         if(!from) {
 314                 logger(mesh, MESHLINK_ERROR, "Got %s from %s which does not appear in the edge tree",
 315                        "DEL_EDGE", c->name);
 316                 return true;
 317         }
 318
 319         if(!to) {
 320                 logger(mesh, MESHLINK_ERROR, "Got %s from %s which does not appear in the edge tree",
 321                        "DEL_EDGE", c->name);
 322                 return true;
 323         }
 324
 325         if(contradictions > 50) {
 326                 handle_duplicate_node(mesh, from);
 327         }
 328
 329         /* Check if edge exists */
 330
 331         e = lookup_edge(from, to);
 332
 333         if(!e) {
 334                 logger(mesh, MESHLINK_WARNING, "Got %s from %s which does not appear in the edge tree",
 335                        "DEL_EDGE", c->name);
 336                 return true;
 337         }
 338
 339         if(e->from == mesh->self) {
 340                 logger(mesh, MESHLINK_WARNING, "Got %s from %s for ourself",
 341                        "DEL_EDGE", c->name);
 342                 mesh->contradicting_del_edge++;
 343                 send_add_edge(mesh, c, e, mesh->contradicting_del_edge);    /* Send back a correction */
 344                 return true;
 345         }
 346
 347         /* Tell the rest about the deleted edge */
 348
 349
 350         if(!e->from->submesh || !e->to->submesh || (e->from->submesh == e->to->submesh)) {
 351                 if(e->from->submesh) {
 352                         s = e->from->submesh;
 353                 } else {
 354                         s = e->to->submesh;
 355                 }
 356
 357                 /* Tell the rest about the deleted edge */
 358                 forward_request(mesh, c, s, request);
 359
 360         } else {
 361                 logger(mesh, MESHLINK_ERROR, "Dropping del edge ( %s to %s )", e->from->submesh->name, e->to->submesh->name);
 362                 return false;
 363         }
 364
 365         /* Delete the edge */
 366
 367         edge_del(mesh, e);
 368
 369         /* Run MST before or after we tell the rest? */
 370
 371         graph(mesh);
 372
 373         /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
 374
 375         if(!to->status.reachable) {
 376                 e = lookup_edge(to, mesh->self);
 377
 378                 if(e) {
 379                         send_del_edge(mesh, mesh->everyone, e, 0);
 380                         edge_del(mesh, e);
 381                 }
 382         }
 383
 384         return true;
 385 }