1 /* 2 * Copyright (c) 2006 Oracle. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 * 32 */ 33 #include <linux/kernel.h> 34 #include <net/sock.h> 35 #include <linux/in.h> 36 #include <linux/if_arp.h> 37 #include "rds.h" 38 39 /* 40 * XXX this probably still needs more work.. no INADDR_ANY, and rbtrees aren't 41 * particularly zippy. 42 * 43 * This is now called for every incoming frame so we arguably care much more 44 * about it than we used to. 45 */ 46 static DEFINE_SPINLOCK(rds_bind_lock); 47 static struct rb_root rds_bind_tree = RB_ROOT; 48 49 static struct rds_sock *rds_bind_tree_walk(__be32 addr, __be16 port, 50 struct rds_sock *insert) 51 { 52 struct rb_node **p = &rds_bind_tree.rb_node; 53 struct rb_node *parent = NULL; 54 struct rds_sock *rs; 55 u64 cmp; 56 u64 needle = ((u64)be32_to_cpu(addr) << 32) | be16_to_cpu(port); 57 58 while (*p) { 59 parent = *p; 60 rs = rb_entry(parent, struct rds_sock, rs_bound_node); 61 62 cmp = ((u64)be32_to_cpu(rs->rs_bound_addr) << 32) | 63 be16_to_cpu(rs->rs_bound_port); 64 65 if (needle < cmp) 66 p = &(*p)->rb_left; 67 else if (needle > cmp) 68 p = &(*p)->rb_right; 69 else 70 return rs; 71 } 72 73 if (insert) { 74 rb_link_node(&insert->rs_bound_node, parent, p); 75 rb_insert_color(&insert->rs_bound_node, &rds_bind_tree); 76 } 77 return NULL; 78 } 79 80 /* 81 * Return the rds_sock bound at the given local address. 82 * 83 * The rx path can race with rds_release. We notice if rds_release() has 84 * marked this socket and don't return a rs ref to the rx path. 85 */ 86 struct rds_sock *rds_find_bound(__be32 addr, __be16 port) 87 { 88 struct rds_sock *rs; 89 unsigned long flags; 90 91 spin_lock_irqsave(&rds_bind_lock, flags); 92 rs = rds_bind_tree_walk(addr, port, NULL); 93 if (rs && !sock_flag(rds_rs_to_sk(rs), SOCK_DEAD)) 94 rds_sock_addref(rs); 95 else 96 rs = NULL; 97 spin_unlock_irqrestore(&rds_bind_lock, flags); 98 99 rdsdebug("returning rs %p for %pI4:%u\n", rs, &addr, 100 ntohs(port)); 101 return rs; 102 } 103 104 /* returns -ve errno or +ve port */ 105 static int rds_add_bound(struct rds_sock *rs, __be32 addr, __be16 *port) 106 { 107 unsigned long flags; 108 int ret = -EADDRINUSE; 109 u16 rover, last; 110 111 if (*port != 0) { 112 rover = be16_to_cpu(*port); 113 last = rover; 114 } else { 115 rover = max_t(u16, net_random(), 2); 116 last = rover - 1; 117 } 118 119 spin_lock_irqsave(&rds_bind_lock, flags); 120 121 do { 122 if (rover == 0) 123 rover++; 124 if (rds_bind_tree_walk(addr, cpu_to_be16(rover), rs) == NULL) { 125 *port = cpu_to_be16(rover); 126 ret = 0; 127 break; 128 } 129 } while (rover++ != last); 130 131 if (ret == 0) { 132 rs->rs_bound_addr = addr; 133 rs->rs_bound_port = *port; 134 rds_sock_addref(rs); 135 136 rdsdebug("rs %p binding to %pI4:%d\n", 137 rs, &addr, (int)ntohs(*port)); 138 } 139 140 spin_unlock_irqrestore(&rds_bind_lock, flags); 141 142 return ret; 143 } 144 145 void rds_remove_bound(struct rds_sock *rs) 146 { 147 unsigned long flags; 148 149 spin_lock_irqsave(&rds_bind_lock, flags); 150 151 if (rs->rs_bound_addr) { 152 rdsdebug("rs %p unbinding from %pI4:%d\n", 153 rs, &rs->rs_bound_addr, 154 ntohs(rs->rs_bound_port)); 155 156 rb_erase(&rs->rs_bound_node, &rds_bind_tree); 157 rds_sock_put(rs); 158 rs->rs_bound_addr = 0; 159 } 160 161 spin_unlock_irqrestore(&rds_bind_lock, flags); 162 } 163 164 int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 165 { 166 struct sock *sk = sock->sk; 167 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr; 168 struct rds_sock *rs = rds_sk_to_rs(sk); 169 struct rds_transport *trans; 170 int ret = 0; 171 172 lock_sock(sk); 173 174 if (addr_len != sizeof(struct sockaddr_in) || 175 sin->sin_family != AF_INET || 176 rs->rs_bound_addr || 177 sin->sin_addr.s_addr == htonl(INADDR_ANY)) { 178 ret = -EINVAL; 179 goto out; 180 } 181 182 ret = rds_add_bound(rs, sin->sin_addr.s_addr, &sin->sin_port); 183 if (ret) 184 goto out; 185 186 trans = rds_trans_get_preferred(sin->sin_addr.s_addr); 187 if (trans == NULL) { 188 ret = -EADDRNOTAVAIL; 189 rds_remove_bound(rs); 190 goto out; 191 } 192 193 rs->rs_transport = trans; 194 ret = 0; 195 196 out: 197 release_sock(sk); 198 return ret; 199 } 200