send.c revision 227293
1249269Sed/*- 2249269Sed * Copyright (c) 2009-2010 Ana Kukec <anchie@FreeBSD.org> 3249269Sed * All rights reserved. 4249269Sed * 5249269Sed * Redistribution and use in source and binary forms, with or without 6249269Sed * modification, are permitted provided that the following conditions 7249269Sed * are met: 8249269Sed * 1. Redistributions of source code must retain the above copyright 9249269Sed * notice, this list of conditions and the following disclaimer. 10249269Sed * 2. Redistributions in binary form must reproduce the above copyright 11249269Sed * notice, this list of conditions and the following disclaimer in the 12249269Sed * documentation and/or other materials provided with the distribution. 13249269Sed * 14249269Sed * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15249269Sed * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16249269Sed * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17249269Sed * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18249269Sed * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19249269Sed * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20249269Sed * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21249269Sed * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22249269Sed * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23249269Sed * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24249269Sed * SUCH DAMAGE. 25249269Sed */ 26249269Sed 27249269Sed#include <sys/cdefs.h> 28249269Sed__FBSDID("$FreeBSD: head/sys/netinet6/send.c 227293 2011-11-07 06:44:47Z ed $"); 29249269Sed 30249269Sed#include <sys/param.h> 31249269Sed#include <sys/kernel.h> 32249269Sed#include <sys/mbuf.h> 33249269Sed#include <sys/module.h> 34249269Sed#include <sys/priv.h> 35249269Sed#include <sys/protosw.h> 36249269Sed#include <sys/systm.h> 37249269Sed#include <sys/socket.h> 38249269Sed#include <sys/sockstate.h> 39249269Sed#include <sys/sockbuf.h> 40249269Sed#include <sys/socketvar.h> 41249269Sed#include <sys/types.h> 42249269Sed 43249269Sed#include <net/route.h> 44249269Sed#include <net/if.h> 45249269Sed#include <net/if_var.h> 46249269Sed#include <net/vnet.h> 47249269Sed 48249269Sed#include <netinet/in.h> 49249269Sed#include <netinet/ip_var.h> 50249269Sed#include <netinet/ip6.h> 51249269Sed#include <netinet/icmp6.h> 52249269Sed 53249269Sed#include <netinet6/in6_var.h> 54249269Sed#include <netinet6/nd6.h> 55249269Sed#include <netinet6/scope6_var.h> 56249269Sed#include <netinet6/send.h> 57249269Sed 58249269Sedstatic MALLOC_DEFINE(M_SEND, "send", "Secure Neighbour Discovery"); 59249269Sed 60249269Sed/* 61249269Sed * The socket used to communicate with the SeND daemon. 62249269Sed */ 63249269Sedstatic VNET_DEFINE(struct socket *, send_so); 64249269Sed#define V_send_so VNET(send_so) 65249269Sed 66249269Sedu_long send_sendspace = 8 * (1024 + sizeof(struct sockaddr_send)); 67249269Sedu_long send_recvspace = 9216; 68249269Sed 69249269Sedstruct mtx send_mtx; 70249269Sed#define SEND_LOCK_INIT() mtx_init(&send_mtx, "send_mtx", NULL, MTX_DEF) 71249269Sed#define SEND_LOCK() mtx_lock(&send_mtx) 72249269Sed#define SEND_UNLOCK() mtx_unlock(&send_mtx) 73249269Sed#define SEND_LOCK_DESTROY() mtx_destroy(&send_mtx) 74249269Sed 75249269Sedstatic int 76249269Sedsend_attach(struct socket *so, int proto, struct thread *td) 77249269Sed{ 78249269Sed int error; 79249269Sed 80249269Sed SEND_LOCK(); 81249269Sed if (V_send_so != NULL) { 82249269Sed SEND_UNLOCK(); 83249269Sed return (EEXIST); 84249269Sed } 85249269Sed 86249269Sed error = priv_check(td, PRIV_NETINET_RAW); 87249269Sed if (error) { 88249269Sed SEND_UNLOCK(); 89249269Sed return(error); 90249269Sed } 91249269Sed 92249269Sed if (proto != IPPROTO_SEND) { 93249269Sed SEND_UNLOCK(); 94249269Sed return (EPROTONOSUPPORT); 95249269Sed } 96249269Sed error = soreserve(so, send_sendspace, send_recvspace); 97249269Sed if (error) { 98249269Sed SEND_UNLOCK(); 99249269Sed return(error); 100249269Sed } 101249269Sed 102249269Sed V_send_so = so; 103249269Sed SEND_UNLOCK(); 104249269Sed 105249269Sed return (0); 106249269Sed} 107249269Sed 108249269Sedstatic int 109249269Sedsend_output(struct mbuf *m, struct ifnet *ifp, int direction) 110249269Sed{ 111249269Sed struct ip6_hdr *ip6; 112249269Sed struct sockaddr_in6 dst; 113249269Sed struct icmp6_hdr *icmp6; 114249269Sed int icmp6len; 115249269Sed 116249269Sed /* 117249269Sed * Receive incoming (SeND-protected) or outgoing traffic 118249269Sed * (SeND-validated) from the SeND user space application. 119249269Sed */ 120249269Sed 121249269Sed switch (direction) { 122249269Sed case SND_IN: 123249269Sed if (m->m_len < (sizeof(struct ip6_hdr) + 124249269Sed sizeof(struct icmp6_hdr))) { 125249269Sed m = m_pullup(m, sizeof(struct ip6_hdr) + 126249269Sed sizeof(struct icmp6_hdr)); 127249269Sed if (!m) 128249269Sed return (ENOBUFS); 129249269Sed } 130249269Sed 131249269Sed /* Before passing off the mbuf record the proper interface. */ 132249269Sed m->m_pkthdr.rcvif = ifp; 133249269Sed 134249269Sed if (m->m_flags & M_PKTHDR) 135249269Sed icmp6len = m->m_pkthdr.len - sizeof(struct ip6_hdr); 136249269Sed else 137249269Sed panic("Doh! not the first mbuf."); 138249269Sed 139249269Sed ip6 = mtod(m, struct ip6_hdr *); 140249269Sed icmp6 = (struct icmp6_hdr *)(ip6 + 1); 141249269Sed 142249269Sed /* 143249269Sed * Output the packet as icmp6.c:icpm6_input() would do. 144249269Sed * The mbuf is always consumed, so we do not have to 145249269Sed * care about that. 146249269Sed */ 147249269Sed switch (icmp6->icmp6_type) { 148249269Sed case ND_NEIGHBOR_SOLICIT: 149249269Sed nd6_ns_input(m, sizeof(struct ip6_hdr), icmp6len); 150249269Sed break; 151249269Sed case ND_NEIGHBOR_ADVERT: 152249269Sed nd6_na_input(m, sizeof(struct ip6_hdr), icmp6len); 153 break; 154 case ND_REDIRECT: 155 icmp6_redirect_input(m, sizeof(struct ip6_hdr)); 156 break; 157 case ND_ROUTER_SOLICIT: 158 nd6_rs_input(m, sizeof(struct ip6_hdr), icmp6len); 159 break; 160 case ND_ROUTER_ADVERT: 161 nd6_ra_input(m, sizeof(struct ip6_hdr), icmp6len); 162 break; 163 default: 164 return (ENOSYS); 165 } 166 return (0); 167 168 case SND_OUT: 169 if (m->m_len < sizeof(struct ip6_hdr)) { 170 m = m_pullup(m, sizeof(struct ip6_hdr)); 171 if (!m) 172 return (ENOBUFS); 173 } 174 ip6 = mtod(m, struct ip6_hdr *); 175 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 176 m->m_flags |= M_MCAST; 177 178 bzero(&dst, sizeof(dst)); 179 dst.sin6_family = AF_INET6; 180 dst.sin6_len = sizeof(dst); 181 dst.sin6_addr = ip6->ip6_dst; 182 183 /* 184 * Output the packet as nd6.c:nd6_output_lle() would do. 185 * The mbuf is always consumed, so we do not have to care 186 * about that. 187 * XXX-BZ as we added data, what about fragmenting, 188 * if now needed? 189 */ 190 int error; 191 error = ((*ifp->if_output)(ifp, m, (struct sockaddr *)&dst, 192 NULL)); 193 if (error) 194 error = ENOENT; 195 return (error); 196 197 default: 198 panic("%s: direction %d neither SND_IN nor SND_OUT.", 199 __func__, direction); 200 } 201} 202 203/* 204 * Receive a SeND message from user space to be either send out by the kernel 205 * or, with SeND ICMPv6 options removed, to be further processed by the icmp6 206 * input path. 207 */ 208static int 209send_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 210 struct mbuf *control, struct thread *td) 211{ 212 struct sockaddr_send *sendsrc; 213 struct ifnet *ifp; 214 int error; 215 216 KASSERT(V_send_so == so, ("%s: socket %p not send socket %p", 217 __func__, so, V_send_so)); 218 219 sendsrc = (struct sockaddr_send *)nam; 220 ifp = ifnet_byindex_ref(sendsrc->send_ifidx); 221 if (ifp == NULL) { 222 error = ENETUNREACH; 223 goto err; 224 } 225 226 error = send_output(m, ifp, sendsrc->send_direction); 227 if_rele(ifp); 228 m = NULL; 229 230err: 231 if (m != NULL) 232 m_freem(m); 233 return (error); 234} 235 236static void 237send_close(struct socket *so) 238{ 239 240 SEND_LOCK(); 241 if (V_send_so) 242 V_send_so = NULL; 243 SEND_UNLOCK(); 244} 245 246/* 247 * Send a SeND message to user space, that was either received and has to be 248 * validated or was about to be send out and has to be handled by the SEND 249 * daemon adding SeND ICMPv6 options. 250 */ 251static int 252send_input(struct mbuf *m, struct ifnet *ifp, int direction, int msglen __unused) 253{ 254 struct ip6_hdr *ip6; 255 struct sockaddr_send sendsrc; 256 257 SEND_LOCK(); 258 if (V_send_so == NULL) { 259 SEND_UNLOCK(); 260 return (-1); 261 } 262 263 /* 264 * Make sure to clear any possible internally embedded scope before 265 * passing the packet to user space for SeND cryptographic signature 266 * validation to succeed. 267 */ 268 ip6 = mtod(m, struct ip6_hdr *); 269 in6_clearscope(&ip6->ip6_src); 270 in6_clearscope(&ip6->ip6_dst); 271 272 bzero(&sendsrc, sizeof(sendsrc)); 273 sendsrc.send_len = sizeof(sendsrc); 274 sendsrc.send_family = AF_INET6; 275 sendsrc.send_direction = direction; 276 sendsrc.send_ifidx = ifp->if_index; 277 278 /* 279 * Send incoming or outgoing traffic to user space either to be 280 * protected (outgoing) or validated (incoming) according to rfc3971. 281 */ 282 SOCKBUF_LOCK(&V_send_so->so_rcv); 283 if (sbappendaddr_locked(&V_send_so->so_rcv, 284 (struct sockaddr *)&sendsrc, m, NULL) == 0) { 285 SOCKBUF_UNLOCK(&V_send_so->so_rcv); 286 /* XXX stats. */ 287 m_freem(m); 288 } else { 289 sorwakeup_locked(V_send_so); 290 } 291 292 SEND_UNLOCK(); 293 return (0); 294} 295 296struct pr_usrreqs send_usrreqs = { 297 .pru_attach = send_attach, 298 .pru_send = send_send, 299 .pru_detach = send_close 300}; 301struct protosw send_protosw = { 302 .pr_type = SOCK_RAW, 303 .pr_flags = PR_ATOMIC|PR_ADDR, 304 .pr_protocol = IPPROTO_SEND, 305 .pr_usrreqs = &send_usrreqs 306}; 307 308static int 309send_modevent(module_t mod, int type, void *unused) 310{ 311#ifdef __notyet__ 312 VNET_ITERATOR_DECL(vnet_iter); 313#endif 314 int error; 315 316 switch (type) { 317 case MOD_LOAD: 318 SEND_LOCK_INIT(); 319 320 error = pf_proto_register(PF_INET6, &send_protosw); 321 if (error != 0) { 322 printf("%s:%d: MOD_LOAD pf_proto_register(): %d\n", 323 __func__, __LINE__, error); 324 SEND_LOCK_DESTROY(); 325 break; 326 } 327 send_sendso_input_hook = send_input; 328 break; 329 case MOD_UNLOAD: 330 /* Do not allow unloading w/o locking. */ 331 return (EBUSY); 332#ifdef __notyet__ 333 VNET_LIST_RLOCK_NOSLEEP(); 334 SEND_LOCK(); 335 VNET_FOREACH(vnet_iter) { 336 CURVNET_SET(vnet_iter); 337 if (V_send_so != NULL) { 338 CURVNET_RESTORE(); 339 SEND_UNLOCK(); 340 VNET_LIST_RUNLOCK_NOSLEEP(); 341 return (EBUSY); 342 } 343 CURVNET_RESTORE(); 344 } 345 SEND_UNLOCK(); 346 VNET_LIST_RUNLOCK_NOSLEEP(); 347 error = pf_proto_unregister(PF_INET6, IPPROTO_SEND, SOCK_RAW); 348 if (error == 0) 349 SEND_LOCK_DESTROY(); 350 send_sendso_input_hook = NULL; 351 break; 352#endif 353 default: 354 error = 0; 355 break; 356 } 357 358 return (error); 359} 360 361static moduledata_t sendmod = { 362 "send", 363 send_modevent, 364 0 365}; 366 367DECLARE_MODULE(send, sendmod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 368