1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/net/sunrpc/svcsock.c 4 * 5 * These are the RPC server socket internals. 6 * 7 * The server scheduling algorithm does not always distribute the load 8 * evenly when servicing a single client. May need to modify the 9 * svc_xprt_enqueue procedure... 10 * 11 * TCP support is largely untested and may be a little slow. The problem 12 * is that we currently do two separate recvfrom's, one for the 4-byte 13 * record length, and the second for the actual record. This could possibly 14 * be improved by always reading a minimum size of around 100 bytes and 15 * tucking any superfluous bytes away in a temporary store. Still, that 16 * leaves write requests out in the rain. An alternative may be to peek at 17 * the first skb in the queue, and if it matches the next TCP sequence 18 * number, to extract the record marker. Yuck. 19 * 20 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/sched.h> 25 #include <linux/module.h> 26 #include <linux/errno.h> 27 #include <linux/fcntl.h> 28 #include <linux/net.h> 29 #include <linux/in.h> 30 #include <linux/inet.h> 31 #include <linux/udp.h> 32 #include <linux/tcp.h> 33 #include <linux/unistd.h> 34 #include <linux/slab.h> 35 #include <linux/netdevice.h> 36 #include <linux/skbuff.h> 37 #include <linux/file.h> 38 #include <linux/freezer.h> 39 #include <net/sock.h> 40 #include <net/checksum.h> 41 #include <net/ip.h> 42 #include <net/ipv6.h> 43 #include <net/udp.h> 44 #include <net/tcp.h> 45 #include <net/tcp_states.h> 46 #include <linux/uaccess.h> 47 #include <asm/ioctls.h> 48 #include <trace/events/skb.h> 49 50 #include <linux/sunrpc/types.h> 51 #include <linux/sunrpc/clnt.h> 52 #include <linux/sunrpc/xdr.h> 53 #include <linux/sunrpc/msg_prot.h> 54 #include <linux/sunrpc/svcsock.h> 55 #include <linux/sunrpc/stats.h> 56 #include <linux/sunrpc/xprt.h> 57 58 #include "socklib.h" 59 #include "sunrpc.h" 60 61 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 62 63 64 static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, 65 int flags); 66 static int svc_udp_recvfrom(struct svc_rqst *); 67 static int svc_udp_sendto(struct svc_rqst *); 68 static void svc_sock_detach(struct svc_xprt *); 69 static void svc_tcp_sock_detach(struct svc_xprt *); 70 static void svc_sock_free(struct svc_xprt *); 71 72 static struct svc_xprt *svc_create_socket(struct svc_serv *, int, 73 struct net *, struct sockaddr *, 74 int, int); 75 #ifdef CONFIG_DEBUG_LOCK_ALLOC 76 static struct lock_class_key svc_key[2]; 77 static struct lock_class_key svc_slock_key[2]; 78 79 static void svc_reclassify_socket(struct socket *sock) 80 { 81 struct sock *sk = sock->sk; 82 83 if (WARN_ON_ONCE(!sock_allow_reclassification(sk))) 84 return; 85 86 switch (sk->sk_family) { 87 case AF_INET: 88 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD", 89 &svc_slock_key[0], 90 "sk_xprt.xpt_lock-AF_INET-NFSD", 91 &svc_key[0]); 92 break; 93 94 case AF_INET6: 95 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD", 96 &svc_slock_key[1], 97 "sk_xprt.xpt_lock-AF_INET6-NFSD", 98 &svc_key[1]); 99 break; 100 101 default: 102 BUG(); 103 } 104 } 105 #else 106 static void svc_reclassify_socket(struct socket *sock) 107 { 108 } 109 #endif 110 111 /* 112 * Release an skbuff after use 113 */ 114 static void svc_release_skb(struct svc_rqst *rqstp) 115 { 116 struct sk_buff *skb = rqstp->rq_xprt_ctxt; 117 118 if (skb) { 119 struct svc_sock *svsk = 120 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 121 rqstp->rq_xprt_ctxt = NULL; 122 123 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb); 124 skb_free_datagram_locked(svsk->sk_sk, skb); 125 } 126 } 127 128 static void svc_release_udp_skb(struct svc_rqst *rqstp) 129 { 130 struct sk_buff *skb = rqstp->rq_xprt_ctxt; 131 132 if (skb) { 133 rqstp->rq_xprt_ctxt = NULL; 134 135 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb); 136 consume_skb(skb); 137 } 138 } 139 140 union svc_pktinfo_u { 141 struct in_pktinfo pkti; 142 struct in6_pktinfo pkti6; 143 }; 144 #define SVC_PKTINFO_SPACE \ 145 CMSG_SPACE(sizeof(union svc_pktinfo_u)) 146 147 static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh) 148 { 149 struct svc_sock *svsk = 150 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 151 switch (svsk->sk_sk->sk_family) { 152 case AF_INET: { 153 struct in_pktinfo *pki = CMSG_DATA(cmh); 154 155 cmh->cmsg_level = SOL_IP; 156 cmh->cmsg_type = IP_PKTINFO; 157 pki->ipi_ifindex = 0; 158 pki->ipi_spec_dst.s_addr = 159 svc_daddr_in(rqstp)->sin_addr.s_addr; 160 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 161 } 162 break; 163 164 case AF_INET6: { 165 struct in6_pktinfo *pki = CMSG_DATA(cmh); 166 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp); 167 168 cmh->cmsg_level = SOL_IPV6; 169 cmh->cmsg_type = IPV6_PKTINFO; 170 pki->ipi6_ifindex = daddr->sin6_scope_id; 171 pki->ipi6_addr = daddr->sin6_addr; 172 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 173 } 174 break; 175 } 176 } 177 178 static int svc_sock_read_payload(struct svc_rqst *rqstp, unsigned int offset, 179 unsigned int length) 180 { 181 return 0; 182 } 183 184 /* 185 * Report socket names for nfsdfs 186 */ 187 static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining) 188 { 189 const struct sock *sk = svsk->sk_sk; 190 const char *proto_name = sk->sk_protocol == IPPROTO_UDP ? 191 "udp" : "tcp"; 192 int len; 193 194 switch (sk->sk_family) { 195 case PF_INET: 196 len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n", 197 proto_name, 198 &inet_sk(sk)->inet_rcv_saddr, 199 inet_sk(sk)->inet_num); 200 break; 201 #if IS_ENABLED(CONFIG_IPV6) 202 case PF_INET6: 203 len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n", 204 proto_name, 205 &sk->sk_v6_rcv_saddr, 206 inet_sk(sk)->inet_num); 207 break; 208 #endif 209 default: 210 len = snprintf(buf, remaining, "*unknown-%d*\n", 211 sk->sk_family); 212 } 213 214 if (len >= remaining) { 215 *buf = '\0'; 216 return -ENAMETOOLONG; 217 } 218 return len; 219 } 220 221 /* 222 * Generic recvfrom routine. 223 */ 224 static ssize_t svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, 225 unsigned int nr, size_t buflen, unsigned int base) 226 { 227 struct svc_sock *svsk = 228 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 229 struct msghdr msg = { NULL }; 230 ssize_t len; 231 232 rqstp->rq_xprt_hlen = 0; 233 234 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 235 iov_iter_kvec(&msg.msg_iter, READ, iov, nr, buflen); 236 if (base != 0) { 237 iov_iter_advance(&msg.msg_iter, base); 238 buflen -= base; 239 } 240 len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT); 241 /* If we read a full record, then assume there may be more 242 * data to read (stream based sockets only!) 243 */ 244 if (len == buflen) 245 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 246 247 dprintk("svc: socket %p recvfrom(%p, %zu) = %zd\n", 248 svsk, iov[0].iov_base, iov[0].iov_len, len); 249 return len; 250 } 251 252 /* 253 * Set socket snd and rcv buffer lengths 254 */ 255 static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs) 256 { 257 unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg; 258 struct socket *sock = svsk->sk_sock; 259 260 nreqs = min(nreqs, INT_MAX / 2 / max_mesg); 261 262 lock_sock(sock->sk); 263 sock->sk->sk_sndbuf = nreqs * max_mesg * 2; 264 sock->sk->sk_rcvbuf = nreqs * max_mesg * 2; 265 sock->sk->sk_write_space(sock->sk); 266 release_sock(sock->sk); 267 } 268 269 static void svc_sock_secure_port(struct svc_rqst *rqstp) 270 { 271 if (svc_port_is_privileged(svc_addr(rqstp))) 272 set_bit(RQ_SECURE, &rqstp->rq_flags); 273 else 274 clear_bit(RQ_SECURE, &rqstp->rq_flags); 275 } 276 277 /* 278 * INET callback when data has been received on the socket. 279 */ 280 static void svc_data_ready(struct sock *sk) 281 { 282 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 283 284 if (svsk) { 285 dprintk("svc: socket %p(inet %p), busy=%d\n", 286 svsk, sk, 287 test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags)); 288 289 /* Refer to svc_setup_socket() for details. */ 290 rmb(); 291 svsk->sk_odata(sk); 292 if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags)) 293 svc_xprt_enqueue(&svsk->sk_xprt); 294 } 295 } 296 297 /* 298 * INET callback when space is newly available on the socket. 299 */ 300 static void svc_write_space(struct sock *sk) 301 { 302 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); 303 304 if (svsk) { 305 dprintk("svc: socket %p(inet %p), write_space busy=%d\n", 306 svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags)); 307 308 /* Refer to svc_setup_socket() for details. */ 309 rmb(); 310 svsk->sk_owspace(sk); 311 svc_xprt_enqueue(&svsk->sk_xprt); 312 } 313 } 314 315 static int svc_tcp_has_wspace(struct svc_xprt *xprt) 316 { 317 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 318 319 if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) 320 return 1; 321 return !test_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 322 } 323 324 static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt) 325 { 326 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 327 328 sock_no_linger(svsk->sk_sock->sk); 329 } 330 331 /* 332 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo 333 */ 334 static int svc_udp_get_dest_address4(struct svc_rqst *rqstp, 335 struct cmsghdr *cmh) 336 { 337 struct in_pktinfo *pki = CMSG_DATA(cmh); 338 struct sockaddr_in *daddr = svc_daddr_in(rqstp); 339 340 if (cmh->cmsg_type != IP_PKTINFO) 341 return 0; 342 343 daddr->sin_family = AF_INET; 344 daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr; 345 return 1; 346 } 347 348 /* 349 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl 350 */ 351 static int svc_udp_get_dest_address6(struct svc_rqst *rqstp, 352 struct cmsghdr *cmh) 353 { 354 struct in6_pktinfo *pki = CMSG_DATA(cmh); 355 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp); 356 357 if (cmh->cmsg_type != IPV6_PKTINFO) 358 return 0; 359 360 daddr->sin6_family = AF_INET6; 361 daddr->sin6_addr = pki->ipi6_addr; 362 daddr->sin6_scope_id = pki->ipi6_ifindex; 363 return 1; 364 } 365 366 /* 367 * Copy the UDP datagram's destination address to the rqstp structure. 368 * The 'destination' address in this case is the address to which the 369 * peer sent the datagram, i.e. our local address. For multihomed 370 * hosts, this can change from msg to msg. Note that only the IP 371 * address changes, the port number should remain the same. 372 */ 373 static int svc_udp_get_dest_address(struct svc_rqst *rqstp, 374 struct cmsghdr *cmh) 375 { 376 switch (cmh->cmsg_level) { 377 case SOL_IP: 378 return svc_udp_get_dest_address4(rqstp, cmh); 379 case SOL_IPV6: 380 return svc_udp_get_dest_address6(rqstp, cmh); 381 } 382 383 return 0; 384 } 385 386 /* 387 * Receive a datagram from a UDP socket. 388 */ 389 static int svc_udp_recvfrom(struct svc_rqst *rqstp) 390 { 391 struct svc_sock *svsk = 392 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 393 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 394 struct sk_buff *skb; 395 union { 396 struct cmsghdr hdr; 397 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 398 } buffer; 399 struct cmsghdr *cmh = &buffer.hdr; 400 struct msghdr msg = { 401 .msg_name = svc_addr(rqstp), 402 .msg_control = cmh, 403 .msg_controllen = sizeof(buffer), 404 .msg_flags = MSG_DONTWAIT, 405 }; 406 size_t len; 407 int err; 408 409 if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags)) 410 /* udp sockets need large rcvbuf as all pending 411 * requests are still in that buffer. sndbuf must 412 * also be large enough that there is enough space 413 * for one reply per thread. We count all threads 414 * rather than threads in a particular pool, which 415 * provides an upper bound on the number of threads 416 * which will access the socket. 417 */ 418 svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3); 419 420 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 421 skb = NULL; 422 err = kernel_recvmsg(svsk->sk_sock, &msg, NULL, 423 0, 0, MSG_PEEK | MSG_DONTWAIT); 424 if (err >= 0) 425 skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err); 426 427 if (skb == NULL) { 428 if (err != -EAGAIN) { 429 /* possibly an icmp error */ 430 dprintk("svc: recvfrom returned error %d\n", -err); 431 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 432 } 433 return 0; 434 } 435 len = svc_addr_len(svc_addr(rqstp)); 436 rqstp->rq_addrlen = len; 437 if (skb->tstamp == 0) { 438 skb->tstamp = ktime_get_real(); 439 /* Don't enable netstamp, sunrpc doesn't 440 need that much accuracy */ 441 } 442 sock_write_timestamp(svsk->sk_sk, skb->tstamp); 443 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */ 444 445 len = skb->len; 446 rqstp->rq_arg.len = len; 447 448 rqstp->rq_prot = IPPROTO_UDP; 449 450 if (!svc_udp_get_dest_address(rqstp, cmh)) { 451 net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n", 452 cmh->cmsg_level, cmh->cmsg_type); 453 goto out_free; 454 } 455 rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp)); 456 457 if (skb_is_nonlinear(skb)) { 458 /* we have to copy */ 459 local_bh_disable(); 460 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) { 461 local_bh_enable(); 462 /* checksum error */ 463 goto out_free; 464 } 465 local_bh_enable(); 466 consume_skb(skb); 467 } else { 468 /* we can use it in-place */ 469 rqstp->rq_arg.head[0].iov_base = skb->data; 470 rqstp->rq_arg.head[0].iov_len = len; 471 if (skb_checksum_complete(skb)) 472 goto out_free; 473 rqstp->rq_xprt_ctxt = skb; 474 } 475 476 rqstp->rq_arg.page_base = 0; 477 if (len <= rqstp->rq_arg.head[0].iov_len) { 478 rqstp->rq_arg.head[0].iov_len = len; 479 rqstp->rq_arg.page_len = 0; 480 rqstp->rq_respages = rqstp->rq_pages+1; 481 } else { 482 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; 483 rqstp->rq_respages = rqstp->rq_pages + 1 + 484 DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE); 485 } 486 rqstp->rq_next_page = rqstp->rq_respages+1; 487 488 if (serv->sv_stats) 489 serv->sv_stats->netudpcnt++; 490 491 return len; 492 out_free: 493 kfree_skb(skb); 494 return 0; 495 } 496 497 /** 498 * svc_udp_sendto - Send out a reply on a UDP socket 499 * @rqstp: completed svc_rqst 500 * 501 * Returns the number of bytes sent, or a negative errno. 502 */ 503 static int svc_udp_sendto(struct svc_rqst *rqstp) 504 { 505 struct svc_xprt *xprt = rqstp->rq_xprt; 506 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 507 struct xdr_buf *xdr = &rqstp->rq_res; 508 union { 509 struct cmsghdr hdr; 510 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 511 } buffer; 512 struct cmsghdr *cmh = &buffer.hdr; 513 struct msghdr msg = { 514 .msg_name = &rqstp->rq_addr, 515 .msg_namelen = rqstp->rq_addrlen, 516 .msg_control = cmh, 517 .msg_controllen = sizeof(buffer), 518 }; 519 unsigned int uninitialized_var(sent); 520 int err; 521 522 svc_release_udp_skb(rqstp); 523 524 svc_set_cmsg_data(rqstp, cmh); 525 526 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent); 527 xdr_free_bvec(xdr); 528 if (err == -ECONNREFUSED) { 529 /* ICMP error on earlier request. */ 530 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent); 531 xdr_free_bvec(xdr); 532 } 533 if (err < 0) 534 return err; 535 return sent; 536 } 537 538 static int svc_udp_has_wspace(struct svc_xprt *xprt) 539 { 540 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 541 struct svc_serv *serv = xprt->xpt_server; 542 unsigned long required; 543 544 /* 545 * Set the SOCK_NOSPACE flag before checking the available 546 * sock space. 547 */ 548 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 549 required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg; 550 if (required*2 > sock_wspace(svsk->sk_sk)) 551 return 0; 552 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 553 return 1; 554 } 555 556 static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt) 557 { 558 BUG(); 559 return NULL; 560 } 561 562 static void svc_udp_kill_temp_xprt(struct svc_xprt *xprt) 563 { 564 } 565 566 static struct svc_xprt *svc_udp_create(struct svc_serv *serv, 567 struct net *net, 568 struct sockaddr *sa, int salen, 569 int flags) 570 { 571 return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags); 572 } 573 574 static const struct svc_xprt_ops svc_udp_ops = { 575 .xpo_create = svc_udp_create, 576 .xpo_recvfrom = svc_udp_recvfrom, 577 .xpo_sendto = svc_udp_sendto, 578 .xpo_read_payload = svc_sock_read_payload, 579 .xpo_release_rqst = svc_release_udp_skb, 580 .xpo_detach = svc_sock_detach, 581 .xpo_free = svc_sock_free, 582 .xpo_has_wspace = svc_udp_has_wspace, 583 .xpo_accept = svc_udp_accept, 584 .xpo_secure_port = svc_sock_secure_port, 585 .xpo_kill_temp_xprt = svc_udp_kill_temp_xprt, 586 }; 587 588 static struct svc_xprt_class svc_udp_class = { 589 .xcl_name = "udp", 590 .xcl_owner = THIS_MODULE, 591 .xcl_ops = &svc_udp_ops, 592 .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP, 593 .xcl_ident = XPRT_TRANSPORT_UDP, 594 }; 595 596 static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv) 597 { 598 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class, 599 &svsk->sk_xprt, serv); 600 clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags); 601 svsk->sk_sk->sk_data_ready = svc_data_ready; 602 svsk->sk_sk->sk_write_space = svc_write_space; 603 604 /* initialise setting must have enough space to 605 * receive and respond to one request. 606 * svc_udp_recvfrom will re-adjust if necessary 607 */ 608 svc_sock_setbufsize(svsk, 3); 609 610 /* data might have come in before data_ready set up */ 611 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 612 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); 613 614 /* make sure we get destination address info */ 615 switch (svsk->sk_sk->sk_family) { 616 case AF_INET: 617 ip_sock_set_pktinfo(svsk->sk_sock->sk); 618 break; 619 case AF_INET6: 620 ip6_sock_set_recvpktinfo(svsk->sk_sock->sk); 621 break; 622 default: 623 BUG(); 624 } 625 } 626 627 /* 628 * A data_ready event on a listening socket means there's a connection 629 * pending. Do not use state_change as a substitute for it. 630 */ 631 static void svc_tcp_listen_data_ready(struct sock *sk) 632 { 633 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 634 635 dprintk("svc: socket %p TCP (listen) state change %d\n", 636 sk, sk->sk_state); 637 638 if (svsk) { 639 /* Refer to svc_setup_socket() for details. */ 640 rmb(); 641 svsk->sk_odata(sk); 642 } 643 644 /* 645 * This callback may called twice when a new connection 646 * is established as a child socket inherits everything 647 * from a parent LISTEN socket. 648 * 1) data_ready method of the parent socket will be called 649 * when one of child sockets become ESTABLISHED. 650 * 2) data_ready method of the child socket may be called 651 * when it receives data before the socket is accepted. 652 * In case of 2, we should ignore it silently. 653 */ 654 if (sk->sk_state == TCP_LISTEN) { 655 if (svsk) { 656 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 657 svc_xprt_enqueue(&svsk->sk_xprt); 658 } else 659 printk("svc: socket %p: no user data\n", sk); 660 } 661 } 662 663 /* 664 * A state change on a connected socket means it's dying or dead. 665 */ 666 static void svc_tcp_state_change(struct sock *sk) 667 { 668 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 669 670 dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n", 671 sk, sk->sk_state, sk->sk_user_data); 672 673 if (!svsk) 674 printk("svc: socket %p: no user data\n", sk); 675 else { 676 /* Refer to svc_setup_socket() for details. */ 677 rmb(); 678 svsk->sk_ostate(sk); 679 if (sk->sk_state != TCP_ESTABLISHED) { 680 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 681 svc_xprt_enqueue(&svsk->sk_xprt); 682 } 683 } 684 } 685 686 /* 687 * Accept a TCP connection 688 */ 689 static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt) 690 { 691 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 692 struct sockaddr_storage addr; 693 struct sockaddr *sin = (struct sockaddr *) &addr; 694 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 695 struct socket *sock = svsk->sk_sock; 696 struct socket *newsock; 697 struct svc_sock *newsvsk; 698 int err, slen; 699 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 700 701 dprintk("svc: tcp_accept %p sock %p\n", svsk, sock); 702 if (!sock) 703 return NULL; 704 705 clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 706 err = kernel_accept(sock, &newsock, O_NONBLOCK); 707 if (err < 0) { 708 if (err == -ENOMEM) 709 printk(KERN_WARNING "%s: no more sockets!\n", 710 serv->sv_name); 711 else if (err != -EAGAIN) 712 net_warn_ratelimited("%s: accept failed (err %d)!\n", 713 serv->sv_name, -err); 714 return NULL; 715 } 716 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 717 718 err = kernel_getpeername(newsock, sin); 719 if (err < 0) { 720 net_warn_ratelimited("%s: peername failed (err %d)!\n", 721 serv->sv_name, -err); 722 goto failed; /* aborted connection or whatever */ 723 } 724 slen = err; 725 726 /* Ideally, we would want to reject connections from unauthorized 727 * hosts here, but when we get encryption, the IP of the host won't 728 * tell us anything. For now just warn about unpriv connections. 729 */ 730 if (!svc_port_is_privileged(sin)) { 731 dprintk("%s: connect from unprivileged port: %s\n", 732 serv->sv_name, 733 __svc_print_addr(sin, buf, sizeof(buf))); 734 } 735 dprintk("%s: connect from %s\n", serv->sv_name, 736 __svc_print_addr(sin, buf, sizeof(buf))); 737 738 /* Reset the inherited callbacks before calling svc_setup_socket */ 739 newsock->sk->sk_state_change = svsk->sk_ostate; 740 newsock->sk->sk_data_ready = svsk->sk_odata; 741 newsock->sk->sk_write_space = svsk->sk_owspace; 742 743 /* make sure that a write doesn't block forever when 744 * low on memory 745 */ 746 newsock->sk->sk_sndtimeo = HZ*30; 747 748 newsvsk = svc_setup_socket(serv, newsock, 749 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY)); 750 if (IS_ERR(newsvsk)) 751 goto failed; 752 svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen); 753 err = kernel_getsockname(newsock, sin); 754 slen = err; 755 if (unlikely(err < 0)) { 756 dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err); 757 slen = offsetof(struct sockaddr, sa_data); 758 } 759 svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen); 760 761 if (sock_is_loopback(newsock->sk)) 762 set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags); 763 else 764 clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags); 765 if (serv->sv_stats) 766 serv->sv_stats->nettcpconn++; 767 768 return &newsvsk->sk_xprt; 769 770 failed: 771 sock_release(newsock); 772 return NULL; 773 } 774 775 static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp) 776 { 777 unsigned int i, len, npages; 778 779 if (svsk->sk_datalen == 0) 780 return 0; 781 len = svsk->sk_datalen; 782 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 783 for (i = 0; i < npages; i++) { 784 if (rqstp->rq_pages[i] != NULL) 785 put_page(rqstp->rq_pages[i]); 786 BUG_ON(svsk->sk_pages[i] == NULL); 787 rqstp->rq_pages[i] = svsk->sk_pages[i]; 788 svsk->sk_pages[i] = NULL; 789 } 790 rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]); 791 return len; 792 } 793 794 static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp) 795 { 796 unsigned int i, len, npages; 797 798 if (svsk->sk_datalen == 0) 799 return; 800 len = svsk->sk_datalen; 801 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 802 for (i = 0; i < npages; i++) { 803 svsk->sk_pages[i] = rqstp->rq_pages[i]; 804 rqstp->rq_pages[i] = NULL; 805 } 806 } 807 808 static void svc_tcp_clear_pages(struct svc_sock *svsk) 809 { 810 unsigned int i, len, npages; 811 812 if (svsk->sk_datalen == 0) 813 goto out; 814 len = svsk->sk_datalen; 815 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 816 for (i = 0; i < npages; i++) { 817 if (svsk->sk_pages[i] == NULL) { 818 WARN_ON_ONCE(1); 819 continue; 820 } 821 put_page(svsk->sk_pages[i]); 822 svsk->sk_pages[i] = NULL; 823 } 824 out: 825 svsk->sk_tcplen = 0; 826 svsk->sk_datalen = 0; 827 } 828 829 /* 830 * Receive fragment record header. 831 * If we haven't gotten the record length yet, get the next four bytes. 832 */ 833 static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp) 834 { 835 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 836 unsigned int want; 837 int len; 838 839 if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) { 840 struct kvec iov; 841 842 want = sizeof(rpc_fraghdr) - svsk->sk_tcplen; 843 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen; 844 iov.iov_len = want; 845 len = svc_recvfrom(rqstp, &iov, 1, want, 0); 846 if (len < 0) 847 goto error; 848 svsk->sk_tcplen += len; 849 850 if (len < want) { 851 dprintk("svc: short recvfrom while reading record " 852 "length (%d of %d)\n", len, want); 853 return -EAGAIN; 854 } 855 856 dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk)); 857 if (svc_sock_reclen(svsk) + svsk->sk_datalen > 858 serv->sv_max_mesg) { 859 net_notice_ratelimited("RPC: fragment too large: %d\n", 860 svc_sock_reclen(svsk)); 861 goto err_delete; 862 } 863 } 864 865 return svc_sock_reclen(svsk); 866 error: 867 dprintk("RPC: TCP recv_record got %d\n", len); 868 return len; 869 err_delete: 870 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 871 return -EAGAIN; 872 } 873 874 static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp) 875 { 876 struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt; 877 struct rpc_rqst *req = NULL; 878 struct kvec *src, *dst; 879 __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base; 880 __be32 xid; 881 __be32 calldir; 882 883 xid = *p++; 884 calldir = *p; 885 886 if (!bc_xprt) 887 return -EAGAIN; 888 spin_lock(&bc_xprt->queue_lock); 889 req = xprt_lookup_rqst(bc_xprt, xid); 890 if (!req) 891 goto unlock_notfound; 892 893 memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf)); 894 /* 895 * XXX!: cheating for now! Only copying HEAD. 896 * But we know this is good enough for now (in fact, for any 897 * callback reply in the forseeable future). 898 */ 899 dst = &req->rq_private_buf.head[0]; 900 src = &rqstp->rq_arg.head[0]; 901 if (dst->iov_len < src->iov_len) 902 goto unlock_eagain; /* whatever; just giving up. */ 903 memcpy(dst->iov_base, src->iov_base, src->iov_len); 904 xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len); 905 rqstp->rq_arg.len = 0; 906 spin_unlock(&bc_xprt->queue_lock); 907 return 0; 908 unlock_notfound: 909 printk(KERN_NOTICE 910 "%s: Got unrecognized reply: " 911 "calldir 0x%x xpt_bc_xprt %p xid %08x\n", 912 __func__, ntohl(calldir), 913 bc_xprt, ntohl(xid)); 914 unlock_eagain: 915 spin_unlock(&bc_xprt->queue_lock); 916 return -EAGAIN; 917 } 918 919 static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len) 920 { 921 int i = 0; 922 int t = 0; 923 924 while (t < len) { 925 vec[i].iov_base = page_address(pages[i]); 926 vec[i].iov_len = PAGE_SIZE; 927 i++; 928 t += PAGE_SIZE; 929 } 930 return i; 931 } 932 933 static void svc_tcp_fragment_received(struct svc_sock *svsk) 934 { 935 /* If we have more data, signal svc_xprt_enqueue() to try again */ 936 dprintk("svc: TCP %s record (%d bytes)\n", 937 svc_sock_final_rec(svsk) ? "final" : "nonfinal", 938 svc_sock_reclen(svsk)); 939 svsk->sk_tcplen = 0; 940 svsk->sk_reclen = 0; 941 } 942 943 /* 944 * Receive data from a TCP socket. 945 */ 946 static int svc_tcp_recvfrom(struct svc_rqst *rqstp) 947 { 948 struct svc_sock *svsk = 949 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 950 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 951 int len; 952 struct kvec *vec; 953 unsigned int want, base; 954 __be32 *p; 955 __be32 calldir; 956 int pnum; 957 958 dprintk("svc: tcp_recv %p data %d conn %d close %d\n", 959 svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags), 960 test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags), 961 test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags)); 962 963 len = svc_tcp_recv_record(svsk, rqstp); 964 if (len < 0) 965 goto error; 966 967 base = svc_tcp_restore_pages(svsk, rqstp); 968 want = svc_sock_reclen(svsk) - (svsk->sk_tcplen - sizeof(rpc_fraghdr)); 969 970 vec = rqstp->rq_vec; 971 972 pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0], base + want); 973 974 rqstp->rq_respages = &rqstp->rq_pages[pnum]; 975 rqstp->rq_next_page = rqstp->rq_respages + 1; 976 977 /* Now receive data */ 978 len = svc_recvfrom(rqstp, vec, pnum, base + want, base); 979 if (len >= 0) { 980 svsk->sk_tcplen += len; 981 svsk->sk_datalen += len; 982 } 983 if (len != want || !svc_sock_final_rec(svsk)) { 984 svc_tcp_save_pages(svsk, rqstp); 985 if (len < 0 && len != -EAGAIN) 986 goto err_delete; 987 if (len == want) 988 svc_tcp_fragment_received(svsk); 989 else 990 dprintk("svc: incomplete TCP record (%d of %d)\n", 991 (int)(svsk->sk_tcplen - sizeof(rpc_fraghdr)), 992 svc_sock_reclen(svsk)); 993 goto err_noclose; 994 } 995 996 if (svsk->sk_datalen < 8) { 997 svsk->sk_datalen = 0; 998 goto err_delete; /* client is nuts. */ 999 } 1000 1001 rqstp->rq_arg.len = svsk->sk_datalen; 1002 rqstp->rq_arg.page_base = 0; 1003 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) { 1004 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len; 1005 rqstp->rq_arg.page_len = 0; 1006 } else 1007 rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; 1008 1009 rqstp->rq_xprt_ctxt = NULL; 1010 rqstp->rq_prot = IPPROTO_TCP; 1011 if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags)) 1012 set_bit(RQ_LOCAL, &rqstp->rq_flags); 1013 else 1014 clear_bit(RQ_LOCAL, &rqstp->rq_flags); 1015 1016 p = (__be32 *)rqstp->rq_arg.head[0].iov_base; 1017 calldir = p[1]; 1018 if (calldir) 1019 len = receive_cb_reply(svsk, rqstp); 1020 1021 /* Reset TCP read info */ 1022 svsk->sk_datalen = 0; 1023 svc_tcp_fragment_received(svsk); 1024 1025 if (len < 0) 1026 goto error; 1027 1028 svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt); 1029 if (serv->sv_stats) 1030 serv->sv_stats->nettcpcnt++; 1031 1032 return rqstp->rq_arg.len; 1033 1034 error: 1035 if (len != -EAGAIN) 1036 goto err_delete; 1037 dprintk("RPC: TCP recvfrom got EAGAIN\n"); 1038 return 0; 1039 err_delete: 1040 printk(KERN_NOTICE "%s: recvfrom returned errno %d\n", 1041 svsk->sk_xprt.xpt_server->sv_name, -len); 1042 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 1043 err_noclose: 1044 return 0; /* record not complete */ 1045 } 1046 1047 /** 1048 * svc_tcp_sendto - Send out a reply on a TCP socket 1049 * @rqstp: completed svc_rqst 1050 * 1051 * Returns the number of bytes sent, or a negative errno. 1052 */ 1053 static int svc_tcp_sendto(struct svc_rqst *rqstp) 1054 { 1055 struct svc_xprt *xprt = rqstp->rq_xprt; 1056 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1057 struct xdr_buf *xdr = &rqstp->rq_res; 1058 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | 1059 (u32)xdr->len); 1060 struct msghdr msg = { 1061 .msg_flags = 0, 1062 }; 1063 unsigned int uninitialized_var(sent); 1064 int err; 1065 1066 svc_release_skb(rqstp); 1067 1068 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, marker, &sent); 1069 xdr_free_bvec(xdr); 1070 if (err < 0 || sent != (xdr->len + sizeof(marker))) 1071 goto out_close; 1072 return sent; 1073 1074 out_close: 1075 pr_notice("rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n", 1076 xprt->xpt_server->sv_name, 1077 (err < 0) ? "got error" : "sent", 1078 (err < 0) ? err : sent, xdr->len); 1079 set_bit(XPT_CLOSE, &xprt->xpt_flags); 1080 svc_xprt_enqueue(xprt); 1081 return -EAGAIN; 1082 } 1083 1084 static struct svc_xprt *svc_tcp_create(struct svc_serv *serv, 1085 struct net *net, 1086 struct sockaddr *sa, int salen, 1087 int flags) 1088 { 1089 return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags); 1090 } 1091 1092 static const struct svc_xprt_ops svc_tcp_ops = { 1093 .xpo_create = svc_tcp_create, 1094 .xpo_recvfrom = svc_tcp_recvfrom, 1095 .xpo_sendto = svc_tcp_sendto, 1096 .xpo_read_payload = svc_sock_read_payload, 1097 .xpo_release_rqst = svc_release_skb, 1098 .xpo_detach = svc_tcp_sock_detach, 1099 .xpo_free = svc_sock_free, 1100 .xpo_has_wspace = svc_tcp_has_wspace, 1101 .xpo_accept = svc_tcp_accept, 1102 .xpo_secure_port = svc_sock_secure_port, 1103 .xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt, 1104 }; 1105 1106 static struct svc_xprt_class svc_tcp_class = { 1107 .xcl_name = "tcp", 1108 .xcl_owner = THIS_MODULE, 1109 .xcl_ops = &svc_tcp_ops, 1110 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, 1111 .xcl_ident = XPRT_TRANSPORT_TCP, 1112 }; 1113 1114 void svc_init_xprt_sock(void) 1115 { 1116 svc_reg_xprt_class(&svc_tcp_class); 1117 svc_reg_xprt_class(&svc_udp_class); 1118 } 1119 1120 void svc_cleanup_xprt_sock(void) 1121 { 1122 svc_unreg_xprt_class(&svc_tcp_class); 1123 svc_unreg_xprt_class(&svc_udp_class); 1124 } 1125 1126 static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv) 1127 { 1128 struct sock *sk = svsk->sk_sk; 1129 1130 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class, 1131 &svsk->sk_xprt, serv); 1132 set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags); 1133 set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags); 1134 if (sk->sk_state == TCP_LISTEN) { 1135 dprintk("setting up TCP socket for listening\n"); 1136 strcpy(svsk->sk_xprt.xpt_remotebuf, "listener"); 1137 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags); 1138 sk->sk_data_ready = svc_tcp_listen_data_ready; 1139 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 1140 } else { 1141 dprintk("setting up TCP socket for reading\n"); 1142 sk->sk_state_change = svc_tcp_state_change; 1143 sk->sk_data_ready = svc_data_ready; 1144 sk->sk_write_space = svc_write_space; 1145 1146 svsk->sk_reclen = 0; 1147 svsk->sk_tcplen = 0; 1148 svsk->sk_datalen = 0; 1149 memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages)); 1150 1151 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; 1152 1153 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 1154 switch (sk->sk_state) { 1155 case TCP_SYN_RECV: 1156 case TCP_ESTABLISHED: 1157 break; 1158 default: 1159 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 1160 } 1161 } 1162 } 1163 1164 void svc_sock_update_bufs(struct svc_serv *serv) 1165 { 1166 /* 1167 * The number of server threads has changed. Update 1168 * rcvbuf and sndbuf accordingly on all sockets 1169 */ 1170 struct svc_sock *svsk; 1171 1172 spin_lock_bh(&serv->sv_lock); 1173 list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) 1174 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); 1175 spin_unlock_bh(&serv->sv_lock); 1176 } 1177 EXPORT_SYMBOL_GPL(svc_sock_update_bufs); 1178 1179 /* 1180 * Initialize socket for RPC use and create svc_sock struct 1181 */ 1182 static struct svc_sock *svc_setup_socket(struct svc_serv *serv, 1183 struct socket *sock, 1184 int flags) 1185 { 1186 struct svc_sock *svsk; 1187 struct sock *inet; 1188 int pmap_register = !(flags & SVC_SOCK_ANONYMOUS); 1189 int err = 0; 1190 1191 dprintk("svc: svc_setup_socket %p\n", sock); 1192 svsk = kzalloc(sizeof(*svsk), GFP_KERNEL); 1193 if (!svsk) 1194 return ERR_PTR(-ENOMEM); 1195 1196 inet = sock->sk; 1197 1198 /* Register socket with portmapper */ 1199 if (pmap_register) 1200 err = svc_register(serv, sock_net(sock->sk), inet->sk_family, 1201 inet->sk_protocol, 1202 ntohs(inet_sk(inet)->inet_sport)); 1203 1204 if (err < 0) { 1205 kfree(svsk); 1206 return ERR_PTR(err); 1207 } 1208 1209 svsk->sk_sock = sock; 1210 svsk->sk_sk = inet; 1211 svsk->sk_ostate = inet->sk_state_change; 1212 svsk->sk_odata = inet->sk_data_ready; 1213 svsk->sk_owspace = inet->sk_write_space; 1214 /* 1215 * This barrier is necessary in order to prevent race condition 1216 * with svc_data_ready(), svc_listen_data_ready() and others 1217 * when calling callbacks above. 1218 */ 1219 wmb(); 1220 inet->sk_user_data = svsk; 1221 1222 /* Initialize the socket */ 1223 if (sock->type == SOCK_DGRAM) 1224 svc_udp_init(svsk, serv); 1225 else 1226 svc_tcp_init(svsk, serv); 1227 1228 dprintk("svc: svc_setup_socket created %p (inet %p), " 1229 "listen %d close %d\n", 1230 svsk, svsk->sk_sk, 1231 test_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags), 1232 test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags)); 1233 1234 return svsk; 1235 } 1236 1237 bool svc_alien_sock(struct net *net, int fd) 1238 { 1239 int err; 1240 struct socket *sock = sockfd_lookup(fd, &err); 1241 bool ret = false; 1242 1243 if (!sock) 1244 goto out; 1245 if (sock_net(sock->sk) != net) 1246 ret = true; 1247 sockfd_put(sock); 1248 out: 1249 return ret; 1250 } 1251 EXPORT_SYMBOL_GPL(svc_alien_sock); 1252 1253 /** 1254 * svc_addsock - add a listener socket to an RPC service 1255 * @serv: pointer to RPC service to which to add a new listener 1256 * @fd: file descriptor of the new listener 1257 * @name_return: pointer to buffer to fill in with name of listener 1258 * @len: size of the buffer 1259 * @cred: credential 1260 * 1261 * Fills in socket name and returns positive length of name if successful. 1262 * Name is terminated with '\n'. On error, returns a negative errno 1263 * value. 1264 */ 1265 int svc_addsock(struct svc_serv *serv, const int fd, char *name_return, 1266 const size_t len, const struct cred *cred) 1267 { 1268 int err = 0; 1269 struct socket *so = sockfd_lookup(fd, &err); 1270 struct svc_sock *svsk = NULL; 1271 struct sockaddr_storage addr; 1272 struct sockaddr *sin = (struct sockaddr *)&addr; 1273 int salen; 1274 1275 if (!so) 1276 return err; 1277 err = -EAFNOSUPPORT; 1278 if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6)) 1279 goto out; 1280 err = -EPROTONOSUPPORT; 1281 if (so->sk->sk_protocol != IPPROTO_TCP && 1282 so->sk->sk_protocol != IPPROTO_UDP) 1283 goto out; 1284 err = -EISCONN; 1285 if (so->state > SS_UNCONNECTED) 1286 goto out; 1287 err = -ENOENT; 1288 if (!try_module_get(THIS_MODULE)) 1289 goto out; 1290 svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS); 1291 if (IS_ERR(svsk)) { 1292 module_put(THIS_MODULE); 1293 err = PTR_ERR(svsk); 1294 goto out; 1295 } 1296 salen = kernel_getsockname(svsk->sk_sock, sin); 1297 if (salen >= 0) 1298 svc_xprt_set_local(&svsk->sk_xprt, sin, salen); 1299 svsk->sk_xprt.xpt_cred = get_cred(cred); 1300 svc_add_new_perm_xprt(serv, &svsk->sk_xprt); 1301 return svc_one_sock_name(svsk, name_return, len); 1302 out: 1303 sockfd_put(so); 1304 return err; 1305 } 1306 EXPORT_SYMBOL_GPL(svc_addsock); 1307 1308 /* 1309 * Create socket for RPC service. 1310 */ 1311 static struct svc_xprt *svc_create_socket(struct svc_serv *serv, 1312 int protocol, 1313 struct net *net, 1314 struct sockaddr *sin, int len, 1315 int flags) 1316 { 1317 struct svc_sock *svsk; 1318 struct socket *sock; 1319 int error; 1320 int type; 1321 struct sockaddr_storage addr; 1322 struct sockaddr *newsin = (struct sockaddr *)&addr; 1323 int newlen; 1324 int family; 1325 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 1326 1327 dprintk("svc: svc_create_socket(%s, %d, %s)\n", 1328 serv->sv_program->pg_name, protocol, 1329 __svc_print_addr(sin, buf, sizeof(buf))); 1330 1331 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) { 1332 printk(KERN_WARNING "svc: only UDP and TCP " 1333 "sockets supported\n"); 1334 return ERR_PTR(-EINVAL); 1335 } 1336 1337 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM; 1338 switch (sin->sa_family) { 1339 case AF_INET6: 1340 family = PF_INET6; 1341 break; 1342 case AF_INET: 1343 family = PF_INET; 1344 break; 1345 default: 1346 return ERR_PTR(-EINVAL); 1347 } 1348 1349 error = __sock_create(net, family, type, protocol, &sock, 1); 1350 if (error < 0) 1351 return ERR_PTR(error); 1352 1353 svc_reclassify_socket(sock); 1354 1355 /* 1356 * If this is an PF_INET6 listener, we want to avoid 1357 * getting requests from IPv4 remotes. Those should 1358 * be shunted to a PF_INET listener via rpcbind. 1359 */ 1360 if (family == PF_INET6) 1361 ip6_sock_set_v6only(sock->sk); 1362 if (type == SOCK_STREAM) 1363 sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */ 1364 error = kernel_bind(sock, sin, len); 1365 if (error < 0) 1366 goto bummer; 1367 1368 error = kernel_getsockname(sock, newsin); 1369 if (error < 0) 1370 goto bummer; 1371 newlen = error; 1372 1373 if (protocol == IPPROTO_TCP) { 1374 if ((error = kernel_listen(sock, 64)) < 0) 1375 goto bummer; 1376 } 1377 1378 svsk = svc_setup_socket(serv, sock, flags); 1379 if (IS_ERR(svsk)) { 1380 error = PTR_ERR(svsk); 1381 goto bummer; 1382 } 1383 svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen); 1384 return (struct svc_xprt *)svsk; 1385 bummer: 1386 dprintk("svc: svc_create_socket error = %d\n", -error); 1387 sock_release(sock); 1388 return ERR_PTR(error); 1389 } 1390 1391 /* 1392 * Detach the svc_sock from the socket so that no 1393 * more callbacks occur. 1394 */ 1395 static void svc_sock_detach(struct svc_xprt *xprt) 1396 { 1397 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1398 struct sock *sk = svsk->sk_sk; 1399 1400 dprintk("svc: svc_sock_detach(%p)\n", svsk); 1401 1402 /* put back the old socket callbacks */ 1403 lock_sock(sk); 1404 sk->sk_state_change = svsk->sk_ostate; 1405 sk->sk_data_ready = svsk->sk_odata; 1406 sk->sk_write_space = svsk->sk_owspace; 1407 sk->sk_user_data = NULL; 1408 release_sock(sk); 1409 } 1410 1411 /* 1412 * Disconnect the socket, and reset the callbacks 1413 */ 1414 static void svc_tcp_sock_detach(struct svc_xprt *xprt) 1415 { 1416 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1417 1418 dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk); 1419 1420 svc_sock_detach(xprt); 1421 1422 if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) { 1423 svc_tcp_clear_pages(svsk); 1424 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR); 1425 } 1426 } 1427 1428 /* 1429 * Free the svc_sock's socket resources and the svc_sock itself. 1430 */ 1431 static void svc_sock_free(struct svc_xprt *xprt) 1432 { 1433 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1434 dprintk("svc: svc_sock_free(%p)\n", svsk); 1435 1436 if (svsk->sk_sock->file) 1437 sockfd_put(svsk->sk_sock); 1438 else 1439 sock_release(svsk->sk_sock); 1440 kfree(svsk); 1441 } 1442