1 /* 2 * net/tipc/discover.c 3 * 4 * Copyright (c) 2003-2006, Ericsson AB 5 * Copyright (c) 2005, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include "core.h" 38 #include "dbg.h" 39 #include "link.h" 40 #include "zone.h" 41 #include "discover.h" 42 #include "port.h" 43 #include "name_table.h" 44 45 #define TIPC_LINK_REQ_INIT 125 /* min delay during bearer start up */ 46 #define TIPC_LINK_REQ_FAST 2000 /* normal delay if bearer has no links */ 47 #define TIPC_LINK_REQ_SLOW 600000 /* normal delay if bearer has links */ 48 49 #if 0 50 #define GET_NODE_INFO 300 51 #define GET_NODE_INFO_RESULT 301 52 #define FORWARD_LINK_PROBE 302 53 #define LINK_REQUEST_REJECTED 303 54 #define LINK_REQUEST_ACCEPTED 304 55 #define DROP_LINK_REQUEST 305 56 #define CHECK_LINK_COUNT 306 57 #endif 58 59 /* 60 * TODO: Most of the inter-cluster setup stuff should be 61 * rewritten, and be made conformant with specification. 62 */ 63 64 65 /** 66 * struct link_req - information about an ongoing link setup request 67 * @bearer: bearer issuing requests 68 * @dest: destination address for request messages 69 * @buf: request message to be (repeatedly) sent 70 * @timer: timer governing period between requests 71 * @timer_intv: current interval between requests (in ms) 72 */ 73 struct link_req { 74 struct bearer *bearer; 75 struct tipc_media_addr dest; 76 struct sk_buff *buf; 77 struct timer_list timer; 78 unsigned int timer_intv; 79 }; 80 81 82 #if 0 83 int disc_create_link(const struct tipc_link_create *argv) 84 { 85 /* 86 * Code for inter cluster link setup here 87 */ 88 return TIPC_OK; 89 } 90 #endif 91 92 /* 93 * disc_lost_link(): A link has lost contact 94 */ 95 96 void tipc_disc_link_event(u32 addr, char *name, int up) 97 { 98 if (in_own_cluster(addr)) 99 return; 100 /* 101 * Code for inter cluster link setup here 102 */ 103 } 104 105 /** 106 * tipc_disc_init_msg - initialize a link setup message 107 * @type: message type (request or response) 108 * @req_links: number of links associated with message 109 * @dest_domain: network domain of node(s) which should respond to message 110 * @b_ptr: ptr to bearer issuing message 111 */ 112 113 static struct sk_buff *tipc_disc_init_msg(u32 type, 114 u32 req_links, 115 u32 dest_domain, 116 struct bearer *b_ptr) 117 { 118 struct sk_buff *buf = buf_acquire(DSC_H_SIZE); 119 struct tipc_msg *msg; 120 121 if (buf) { 122 msg = buf_msg(buf); 123 msg_init(msg, LINK_CONFIG, type, TIPC_OK, DSC_H_SIZE, 124 dest_domain); 125 msg_set_non_seq(msg); 126 msg_set_req_links(msg, req_links); 127 msg_set_dest_domain(msg, dest_domain); 128 msg_set_bc_netid(msg, tipc_net_id); 129 msg_set_media_addr(msg, &b_ptr->publ.addr); 130 } 131 return buf; 132 } 133 134 /** 135 * tipc_disc_recv_msg - handle incoming link setup message (request or response) 136 * @buf: buffer containing message 137 */ 138 139 void tipc_disc_recv_msg(struct sk_buff *buf) 140 { 141 struct bearer *b_ptr = (struct bearer *)TIPC_SKB_CB(buf)->handle; 142 struct link *link; 143 struct tipc_media_addr media_addr; 144 struct tipc_msg *msg = buf_msg(buf); 145 u32 dest = msg_dest_domain(msg); 146 u32 orig = msg_prevnode(msg); 147 u32 net_id = msg_bc_netid(msg); 148 u32 type = msg_type(msg); 149 150 msg_get_media_addr(msg,&media_addr); 151 msg_dbg(msg, "RECV:"); 152 buf_discard(buf); 153 154 if (net_id != tipc_net_id) 155 return; 156 if (!tipc_addr_domain_valid(dest)) 157 return; 158 if (!tipc_addr_node_valid(orig)) 159 return; 160 if (orig == tipc_own_addr) 161 return; 162 if (!in_scope(dest, tipc_own_addr)) 163 return; 164 if (is_slave(tipc_own_addr) && is_slave(orig)) 165 return; 166 if (is_slave(orig) && !in_own_cluster(orig)) 167 return; 168 if (in_own_cluster(orig)) { 169 /* Always accept link here */ 170 struct sk_buff *rbuf; 171 struct tipc_media_addr *addr; 172 struct node *n_ptr = tipc_node_find(orig); 173 int link_up; 174 dbg(" in own cluster\n"); 175 if (n_ptr == NULL) { 176 n_ptr = tipc_node_create(orig); 177 } 178 if (n_ptr == NULL) { 179 warn("Memory squeeze; Failed to create node\n"); 180 return; 181 } 182 spin_lock_bh(&n_ptr->lock); 183 link = n_ptr->links[b_ptr->identity]; 184 if (!link) { 185 dbg("creating link\n"); 186 link = tipc_link_create(b_ptr, orig, &media_addr); 187 if (!link) { 188 spin_unlock_bh(&n_ptr->lock); 189 return; 190 } 191 } 192 addr = &link->media_addr; 193 if (memcmp(addr, &media_addr, sizeof(*addr))) { 194 char addr_string[16]; 195 196 warn("New bearer address for %s\n", 197 addr_string_fill(addr_string, orig)); 198 memcpy(addr, &media_addr, sizeof(*addr)); 199 tipc_link_reset(link); 200 } 201 link_up = tipc_link_is_up(link); 202 spin_unlock_bh(&n_ptr->lock); 203 if ((type == DSC_RESP_MSG) || link_up) 204 return; 205 rbuf = tipc_disc_init_msg(DSC_RESP_MSG, 1, orig, b_ptr); 206 if (rbuf != NULL) { 207 msg_dbg(buf_msg(rbuf),"SEND:"); 208 b_ptr->media->send_msg(rbuf, &b_ptr->publ, &media_addr); 209 buf_discard(rbuf); 210 } 211 } 212 } 213 214 /** 215 * tipc_disc_stop_link_req - stop sending periodic link setup requests 216 * @req: ptr to link request structure 217 */ 218 219 void tipc_disc_stop_link_req(struct link_req *req) 220 { 221 if (!req) 222 return; 223 224 k_cancel_timer(&req->timer); 225 k_term_timer(&req->timer); 226 buf_discard(req->buf); 227 kfree(req); 228 } 229 230 /** 231 * tipc_disc_update_link_req - update frequency of periodic link setup requests 232 * @req: ptr to link request structure 233 */ 234 235 void tipc_disc_update_link_req(struct link_req *req) 236 { 237 if (!req) 238 return; 239 240 if (req->timer_intv == TIPC_LINK_REQ_SLOW) { 241 if (!req->bearer->nodes.count) { 242 req->timer_intv = TIPC_LINK_REQ_FAST; 243 k_start_timer(&req->timer, req->timer_intv); 244 } 245 } else if (req->timer_intv == TIPC_LINK_REQ_FAST) { 246 if (req->bearer->nodes.count) { 247 req->timer_intv = TIPC_LINK_REQ_SLOW; 248 k_start_timer(&req->timer, req->timer_intv); 249 } 250 } else { 251 /* leave timer "as is" if haven't yet reached a "normal" rate */ 252 } 253 } 254 255 /** 256 * disc_timeout - send a periodic link setup request 257 * @req: ptr to link request structure 258 * 259 * Called whenever a link setup request timer associated with a bearer expires. 260 */ 261 262 static void disc_timeout(struct link_req *req) 263 { 264 spin_lock_bh(&req->bearer->publ.lock); 265 266 req->bearer->media->send_msg(req->buf, &req->bearer->publ, &req->dest); 267 268 if ((req->timer_intv == TIPC_LINK_REQ_SLOW) || 269 (req->timer_intv == TIPC_LINK_REQ_FAST)) { 270 /* leave timer interval "as is" if already at a "normal" rate */ 271 } else { 272 req->timer_intv *= 2; 273 if (req->timer_intv > TIPC_LINK_REQ_SLOW) 274 req->timer_intv = TIPC_LINK_REQ_SLOW; 275 if ((req->timer_intv == TIPC_LINK_REQ_FAST) && 276 (req->bearer->nodes.count)) 277 req->timer_intv = TIPC_LINK_REQ_SLOW; 278 } 279 k_start_timer(&req->timer, req->timer_intv); 280 281 spin_unlock_bh(&req->bearer->publ.lock); 282 } 283 284 /** 285 * tipc_disc_init_link_req - start sending periodic link setup requests 286 * @b_ptr: ptr to bearer issuing requests 287 * @dest: destination address for request messages 288 * @dest_domain: network domain of node(s) which should respond to message 289 * @req_links: max number of desired links 290 * 291 * Returns pointer to link request structure, or NULL if unable to create. 292 */ 293 294 struct link_req *tipc_disc_init_link_req(struct bearer *b_ptr, 295 const struct tipc_media_addr *dest, 296 u32 dest_domain, 297 u32 req_links) 298 { 299 struct link_req *req; 300 301 req = (struct link_req *)kmalloc(sizeof(*req), GFP_ATOMIC); 302 if (!req) 303 return NULL; 304 305 req->buf = tipc_disc_init_msg(DSC_REQ_MSG, req_links, dest_domain, b_ptr); 306 if (!req->buf) { 307 kfree(req); 308 return NULL; 309 } 310 311 memcpy(&req->dest, dest, sizeof(*dest)); 312 req->bearer = b_ptr; 313 req->timer_intv = TIPC_LINK_REQ_INIT; 314 k_init_timer(&req->timer, (Handler)disc_timeout, (unsigned long)req); 315 k_start_timer(&req->timer, req->timer_intv); 316 return req; 317 } 318 319