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 <linux/highmem.h> 48 #include <asm/ioctls.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 <trace/events/sunrpc.h> 59 60 #include "socklib.h" 61 #include "sunrpc.h" 62 63 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 64 65 66 static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, 67 int flags); 68 static int svc_udp_recvfrom(struct svc_rqst *); 69 static int svc_udp_sendto(struct svc_rqst *); 70 static void svc_sock_detach(struct svc_xprt *); 71 static void svc_tcp_sock_detach(struct svc_xprt *); 72 static void svc_sock_free(struct svc_xprt *); 73 74 static struct svc_xprt *svc_create_socket(struct svc_serv *, int, 75 struct net *, struct sockaddr *, 76 int, int); 77 #ifdef CONFIG_DEBUG_LOCK_ALLOC 78 static struct lock_class_key svc_key[2]; 79 static struct lock_class_key svc_slock_key[2]; 80 81 static void svc_reclassify_socket(struct socket *sock) 82 { 83 struct sock *sk = sock->sk; 84 85 if (WARN_ON_ONCE(!sock_allow_reclassification(sk))) 86 return; 87 88 switch (sk->sk_family) { 89 case AF_INET: 90 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD", 91 &svc_slock_key[0], 92 "sk_xprt.xpt_lock-AF_INET-NFSD", 93 &svc_key[0]); 94 break; 95 96 case AF_INET6: 97 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD", 98 &svc_slock_key[1], 99 "sk_xprt.xpt_lock-AF_INET6-NFSD", 100 &svc_key[1]); 101 break; 102 103 default: 104 BUG(); 105 } 106 } 107 #else 108 static void svc_reclassify_socket(struct socket *sock) 109 { 110 } 111 #endif 112 113 /** 114 * svc_tcp_release_rqst - Release transport-related resources 115 * @rqstp: request structure with resources to be released 116 * 117 */ 118 static void svc_tcp_release_rqst(struct svc_rqst *rqstp) 119 { 120 struct sk_buff *skb = rqstp->rq_xprt_ctxt; 121 122 if (skb) { 123 struct svc_sock *svsk = 124 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 125 126 rqstp->rq_xprt_ctxt = NULL; 127 skb_free_datagram_locked(svsk->sk_sk, skb); 128 } 129 } 130 131 /** 132 * svc_udp_release_rqst - Release transport-related resources 133 * @rqstp: request structure with resources to be released 134 * 135 */ 136 static void svc_udp_release_rqst(struct svc_rqst *rqstp) 137 { 138 struct sk_buff *skb = rqstp->rq_xprt_ctxt; 139 140 if (skb) { 141 rqstp->rq_xprt_ctxt = NULL; 142 consume_skb(skb); 143 } 144 } 145 146 union svc_pktinfo_u { 147 struct in_pktinfo pkti; 148 struct in6_pktinfo pkti6; 149 }; 150 #define SVC_PKTINFO_SPACE \ 151 CMSG_SPACE(sizeof(union svc_pktinfo_u)) 152 153 static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh) 154 { 155 struct svc_sock *svsk = 156 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 157 switch (svsk->sk_sk->sk_family) { 158 case AF_INET: { 159 struct in_pktinfo *pki = CMSG_DATA(cmh); 160 161 cmh->cmsg_level = SOL_IP; 162 cmh->cmsg_type = IP_PKTINFO; 163 pki->ipi_ifindex = 0; 164 pki->ipi_spec_dst.s_addr = 165 svc_daddr_in(rqstp)->sin_addr.s_addr; 166 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 167 } 168 break; 169 170 case AF_INET6: { 171 struct in6_pktinfo *pki = CMSG_DATA(cmh); 172 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp); 173 174 cmh->cmsg_level = SOL_IPV6; 175 cmh->cmsg_type = IPV6_PKTINFO; 176 pki->ipi6_ifindex = daddr->sin6_scope_id; 177 pki->ipi6_addr = daddr->sin6_addr; 178 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 179 } 180 break; 181 } 182 } 183 184 static int svc_sock_read_payload(struct svc_rqst *rqstp, unsigned int offset, 185 unsigned int length) 186 { 187 return 0; 188 } 189 190 /* 191 * Report socket names for nfsdfs 192 */ 193 static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining) 194 { 195 const struct sock *sk = svsk->sk_sk; 196 const char *proto_name = sk->sk_protocol == IPPROTO_UDP ? 197 "udp" : "tcp"; 198 int len; 199 200 switch (sk->sk_family) { 201 case PF_INET: 202 len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n", 203 proto_name, 204 &inet_sk(sk)->inet_rcv_saddr, 205 inet_sk(sk)->inet_num); 206 break; 207 #if IS_ENABLED(CONFIG_IPV6) 208 case PF_INET6: 209 len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n", 210 proto_name, 211 &sk->sk_v6_rcv_saddr, 212 inet_sk(sk)->inet_num); 213 break; 214 #endif 215 default: 216 len = snprintf(buf, remaining, "*unknown-%d*\n", 217 sk->sk_family); 218 } 219 220 if (len >= remaining) { 221 *buf = '\0'; 222 return -ENAMETOOLONG; 223 } 224 return len; 225 } 226 227 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 228 static void svc_flush_bvec(const struct bio_vec *bvec, size_t size, size_t seek) 229 { 230 struct bvec_iter bi = { 231 .bi_size = size, 232 }; 233 struct bio_vec bv; 234 235 bvec_iter_advance(bvec, &bi, seek & PAGE_MASK); 236 for_each_bvec(bv, bvec, bi, bi) 237 flush_dcache_page(bv.bv_page); 238 } 239 #else 240 static inline void svc_flush_bvec(const struct bio_vec *bvec, size_t size, 241 size_t seek) 242 { 243 } 244 #endif 245 246 /* 247 * Read from @rqstp's transport socket. The incoming message fills whole 248 * pages in @rqstp's rq_pages array until the last page of the message 249 * has been received into a partial page. 250 */ 251 static ssize_t svc_tcp_read_msg(struct svc_rqst *rqstp, size_t buflen, 252 size_t seek) 253 { 254 struct svc_sock *svsk = 255 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 256 struct bio_vec *bvec = rqstp->rq_bvec; 257 struct msghdr msg = { NULL }; 258 unsigned int i; 259 ssize_t len; 260 size_t t; 261 262 rqstp->rq_xprt_hlen = 0; 263 264 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 265 266 for (i = 0, t = 0; t < buflen; i++, t += PAGE_SIZE) { 267 bvec[i].bv_page = rqstp->rq_pages[i]; 268 bvec[i].bv_len = PAGE_SIZE; 269 bvec[i].bv_offset = 0; 270 } 271 rqstp->rq_respages = &rqstp->rq_pages[i]; 272 rqstp->rq_next_page = rqstp->rq_respages + 1; 273 274 iov_iter_bvec(&msg.msg_iter, READ, bvec, i, buflen); 275 if (seek) { 276 iov_iter_advance(&msg.msg_iter, seek); 277 buflen -= seek; 278 } 279 len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT); 280 if (len > 0) 281 svc_flush_bvec(bvec, len, seek); 282 283 /* If we read a full record, then assume there may be more 284 * data to read (stream based sockets only!) 285 */ 286 if (len == buflen) 287 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 288 289 return len; 290 } 291 292 /* 293 * Set socket snd and rcv buffer lengths 294 */ 295 static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs) 296 { 297 unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg; 298 struct socket *sock = svsk->sk_sock; 299 300 nreqs = min(nreqs, INT_MAX / 2 / max_mesg); 301 302 lock_sock(sock->sk); 303 sock->sk->sk_sndbuf = nreqs * max_mesg * 2; 304 sock->sk->sk_rcvbuf = nreqs * max_mesg * 2; 305 sock->sk->sk_write_space(sock->sk); 306 release_sock(sock->sk); 307 } 308 309 static void svc_sock_secure_port(struct svc_rqst *rqstp) 310 { 311 if (svc_port_is_privileged(svc_addr(rqstp))) 312 set_bit(RQ_SECURE, &rqstp->rq_flags); 313 else 314 clear_bit(RQ_SECURE, &rqstp->rq_flags); 315 } 316 317 /* 318 * INET callback when data has been received on the socket. 319 */ 320 static void svc_data_ready(struct sock *sk) 321 { 322 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 323 324 if (svsk) { 325 /* Refer to svc_setup_socket() for details. */ 326 rmb(); 327 svsk->sk_odata(sk); 328 trace_svcsock_data_ready(&svsk->sk_xprt, 0); 329 if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags)) 330 svc_xprt_enqueue(&svsk->sk_xprt); 331 } 332 } 333 334 /* 335 * INET callback when space is newly available on the socket. 336 */ 337 static void svc_write_space(struct sock *sk) 338 { 339 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); 340 341 if (svsk) { 342 /* Refer to svc_setup_socket() for details. */ 343 rmb(); 344 trace_svcsock_write_space(&svsk->sk_xprt, 0); 345 svsk->sk_owspace(sk); 346 svc_xprt_enqueue(&svsk->sk_xprt); 347 } 348 } 349 350 static int svc_tcp_has_wspace(struct svc_xprt *xprt) 351 { 352 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 353 354 if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) 355 return 1; 356 return !test_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 357 } 358 359 static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt) 360 { 361 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 362 363 sock_no_linger(svsk->sk_sock->sk); 364 } 365 366 /* 367 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo 368 */ 369 static int svc_udp_get_dest_address4(struct svc_rqst *rqstp, 370 struct cmsghdr *cmh) 371 { 372 struct in_pktinfo *pki = CMSG_DATA(cmh); 373 struct sockaddr_in *daddr = svc_daddr_in(rqstp); 374 375 if (cmh->cmsg_type != IP_PKTINFO) 376 return 0; 377 378 daddr->sin_family = AF_INET; 379 daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr; 380 return 1; 381 } 382 383 /* 384 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl 385 */ 386 static int svc_udp_get_dest_address6(struct svc_rqst *rqstp, 387 struct cmsghdr *cmh) 388 { 389 struct in6_pktinfo *pki = CMSG_DATA(cmh); 390 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp); 391 392 if (cmh->cmsg_type != IPV6_PKTINFO) 393 return 0; 394 395 daddr->sin6_family = AF_INET6; 396 daddr->sin6_addr = pki->ipi6_addr; 397 daddr->sin6_scope_id = pki->ipi6_ifindex; 398 return 1; 399 } 400 401 /* 402 * Copy the UDP datagram's destination address to the rqstp structure. 403 * The 'destination' address in this case is the address to which the 404 * peer sent the datagram, i.e. our local address. For multihomed 405 * hosts, this can change from msg to msg. Note that only the IP 406 * address changes, the port number should remain the same. 407 */ 408 static int svc_udp_get_dest_address(struct svc_rqst *rqstp, 409 struct cmsghdr *cmh) 410 { 411 switch (cmh->cmsg_level) { 412 case SOL_IP: 413 return svc_udp_get_dest_address4(rqstp, cmh); 414 case SOL_IPV6: 415 return svc_udp_get_dest_address6(rqstp, cmh); 416 } 417 418 return 0; 419 } 420 421 /** 422 * svc_udp_recvfrom - Receive a datagram from a UDP socket. 423 * @rqstp: request structure into which to receive an RPC Call 424 * 425 * Called in a loop when XPT_DATA has been set. 426 * 427 * Returns: 428 * On success, the number of bytes in a received RPC Call, or 429 * %0 if a complete RPC Call message was not ready to return 430 */ 431 static int svc_udp_recvfrom(struct svc_rqst *rqstp) 432 { 433 struct svc_sock *svsk = 434 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 435 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 436 struct sk_buff *skb; 437 union { 438 struct cmsghdr hdr; 439 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 440 } buffer; 441 struct cmsghdr *cmh = &buffer.hdr; 442 struct msghdr msg = { 443 .msg_name = svc_addr(rqstp), 444 .msg_control = cmh, 445 .msg_controllen = sizeof(buffer), 446 .msg_flags = MSG_DONTWAIT, 447 }; 448 size_t len; 449 int err; 450 451 if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags)) 452 /* udp sockets need large rcvbuf as all pending 453 * requests are still in that buffer. sndbuf must 454 * also be large enough that there is enough space 455 * for one reply per thread. We count all threads 456 * rather than threads in a particular pool, which 457 * provides an upper bound on the number of threads 458 * which will access the socket. 459 */ 460 svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3); 461 462 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 463 err = kernel_recvmsg(svsk->sk_sock, &msg, NULL, 464 0, 0, MSG_PEEK | MSG_DONTWAIT); 465 if (err < 0) 466 goto out_recv_err; 467 skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err); 468 if (!skb) 469 goto out_recv_err; 470 471 len = svc_addr_len(svc_addr(rqstp)); 472 rqstp->rq_addrlen = len; 473 if (skb->tstamp == 0) { 474 skb->tstamp = ktime_get_real(); 475 /* Don't enable netstamp, sunrpc doesn't 476 need that much accuracy */ 477 } 478 sock_write_timestamp(svsk->sk_sk, skb->tstamp); 479 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */ 480 481 len = skb->len; 482 rqstp->rq_arg.len = len; 483 trace_svcsock_udp_recv(&svsk->sk_xprt, len); 484 485 rqstp->rq_prot = IPPROTO_UDP; 486 487 if (!svc_udp_get_dest_address(rqstp, cmh)) 488 goto out_cmsg_err; 489 rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp)); 490 491 if (skb_is_nonlinear(skb)) { 492 /* we have to copy */ 493 local_bh_disable(); 494 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) 495 goto out_bh_enable; 496 local_bh_enable(); 497 consume_skb(skb); 498 } else { 499 /* we can use it in-place */ 500 rqstp->rq_arg.head[0].iov_base = skb->data; 501 rqstp->rq_arg.head[0].iov_len = len; 502 if (skb_checksum_complete(skb)) 503 goto out_free; 504 rqstp->rq_xprt_ctxt = skb; 505 } 506 507 rqstp->rq_arg.page_base = 0; 508 if (len <= rqstp->rq_arg.head[0].iov_len) { 509 rqstp->rq_arg.head[0].iov_len = len; 510 rqstp->rq_arg.page_len = 0; 511 rqstp->rq_respages = rqstp->rq_pages+1; 512 } else { 513 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; 514 rqstp->rq_respages = rqstp->rq_pages + 1 + 515 DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE); 516 } 517 rqstp->rq_next_page = rqstp->rq_respages+1; 518 519 if (serv->sv_stats) 520 serv->sv_stats->netudpcnt++; 521 522 return len; 523 524 out_recv_err: 525 if (err != -EAGAIN) { 526 /* possibly an icmp error */ 527 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 528 } 529 trace_svcsock_udp_recv_err(&svsk->sk_xprt, err); 530 return 0; 531 out_cmsg_err: 532 net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n", 533 cmh->cmsg_level, cmh->cmsg_type); 534 goto out_free; 535 out_bh_enable: 536 local_bh_enable(); 537 out_free: 538 kfree_skb(skb); 539 return 0; 540 } 541 542 /** 543 * svc_udp_sendto - Send out a reply on a UDP socket 544 * @rqstp: completed svc_rqst 545 * 546 * xpt_mutex ensures @rqstp's whole message is written to the socket 547 * without interruption. 548 * 549 * Returns the number of bytes sent, or a negative errno. 550 */ 551 static int svc_udp_sendto(struct svc_rqst *rqstp) 552 { 553 struct svc_xprt *xprt = rqstp->rq_xprt; 554 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 555 struct xdr_buf *xdr = &rqstp->rq_res; 556 union { 557 struct cmsghdr hdr; 558 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 559 } buffer; 560 struct cmsghdr *cmh = &buffer.hdr; 561 struct msghdr msg = { 562 .msg_name = &rqstp->rq_addr, 563 .msg_namelen = rqstp->rq_addrlen, 564 .msg_control = cmh, 565 .msg_controllen = sizeof(buffer), 566 }; 567 unsigned int sent; 568 int err; 569 570 svc_udp_release_rqst(rqstp); 571 572 svc_set_cmsg_data(rqstp, cmh); 573 574 mutex_lock(&xprt->xpt_mutex); 575 576 if (svc_xprt_is_dead(xprt)) 577 goto out_notconn; 578 579 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent); 580 xdr_free_bvec(xdr); 581 if (err == -ECONNREFUSED) { 582 /* ICMP error on earlier request. */ 583 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent); 584 xdr_free_bvec(xdr); 585 } 586 trace_svcsock_udp_send(xprt, err); 587 588 mutex_unlock(&xprt->xpt_mutex); 589 if (err < 0) 590 return err; 591 return sent; 592 593 out_notconn: 594 mutex_unlock(&xprt->xpt_mutex); 595 return -ENOTCONN; 596 } 597 598 static int svc_udp_has_wspace(struct svc_xprt *xprt) 599 { 600 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 601 struct svc_serv *serv = xprt->xpt_server; 602 unsigned long required; 603 604 /* 605 * Set the SOCK_NOSPACE flag before checking the available 606 * sock space. 607 */ 608 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 609 required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg; 610 if (required*2 > sock_wspace(svsk->sk_sk)) 611 return 0; 612 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 613 return 1; 614 } 615 616 static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt) 617 { 618 BUG(); 619 return NULL; 620 } 621 622 static void svc_udp_kill_temp_xprt(struct svc_xprt *xprt) 623 { 624 } 625 626 static struct svc_xprt *svc_udp_create(struct svc_serv *serv, 627 struct net *net, 628 struct sockaddr *sa, int salen, 629 int flags) 630 { 631 return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags); 632 } 633 634 static const struct svc_xprt_ops svc_udp_ops = { 635 .xpo_create = svc_udp_create, 636 .xpo_recvfrom = svc_udp_recvfrom, 637 .xpo_sendto = svc_udp_sendto, 638 .xpo_read_payload = svc_sock_read_payload, 639 .xpo_release_rqst = svc_udp_release_rqst, 640 .xpo_detach = svc_sock_detach, 641 .xpo_free = svc_sock_free, 642 .xpo_has_wspace = svc_udp_has_wspace, 643 .xpo_accept = svc_udp_accept, 644 .xpo_secure_port = svc_sock_secure_port, 645 .xpo_kill_temp_xprt = svc_udp_kill_temp_xprt, 646 }; 647 648 static struct svc_xprt_class svc_udp_class = { 649 .xcl_name = "udp", 650 .xcl_owner = THIS_MODULE, 651 .xcl_ops = &svc_udp_ops, 652 .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP, 653 .xcl_ident = XPRT_TRANSPORT_UDP, 654 }; 655 656 static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv) 657 { 658 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class, 659 &svsk->sk_xprt, serv); 660 clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags); 661 svsk->sk_sk->sk_data_ready = svc_data_ready; 662 svsk->sk_sk->sk_write_space = svc_write_space; 663 664 /* initialise setting must have enough space to 665 * receive and respond to one request. 666 * svc_udp_recvfrom will re-adjust if necessary 667 */ 668 svc_sock_setbufsize(svsk, 3); 669 670 /* data might have come in before data_ready set up */ 671 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 672 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); 673 674 /* make sure we get destination address info */ 675 switch (svsk->sk_sk->sk_family) { 676 case AF_INET: 677 ip_sock_set_pktinfo(svsk->sk_sock->sk); 678 break; 679 case AF_INET6: 680 ip6_sock_set_recvpktinfo(svsk->sk_sock->sk); 681 break; 682 default: 683 BUG(); 684 } 685 } 686 687 /* 688 * A data_ready event on a listening socket means there's a connection 689 * pending. Do not use state_change as a substitute for it. 690 */ 691 static void svc_tcp_listen_data_ready(struct sock *sk) 692 { 693 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 694 695 if (svsk) { 696 /* Refer to svc_setup_socket() for details. */ 697 rmb(); 698 svsk->sk_odata(sk); 699 } 700 701 /* 702 * This callback may called twice when a new connection 703 * is established as a child socket inherits everything 704 * from a parent LISTEN socket. 705 * 1) data_ready method of the parent socket will be called 706 * when one of child sockets become ESTABLISHED. 707 * 2) data_ready method of the child socket may be called 708 * when it receives data before the socket is accepted. 709 * In case of 2, we should ignore it silently. 710 */ 711 if (sk->sk_state == TCP_LISTEN) { 712 if (svsk) { 713 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 714 svc_xprt_enqueue(&svsk->sk_xprt); 715 } 716 } 717 } 718 719 /* 720 * A state change on a connected socket means it's dying or dead. 721 */ 722 static void svc_tcp_state_change(struct sock *sk) 723 { 724 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 725 726 if (svsk) { 727 /* Refer to svc_setup_socket() for details. */ 728 rmb(); 729 svsk->sk_ostate(sk); 730 trace_svcsock_tcp_state(&svsk->sk_xprt, svsk->sk_sock); 731 if (sk->sk_state != TCP_ESTABLISHED) { 732 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 733 svc_xprt_enqueue(&svsk->sk_xprt); 734 } 735 } 736 } 737 738 /* 739 * Accept a TCP connection 740 */ 741 static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt) 742 { 743 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 744 struct sockaddr_storage addr; 745 struct sockaddr *sin = (struct sockaddr *) &addr; 746 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 747 struct socket *sock = svsk->sk_sock; 748 struct socket *newsock; 749 struct svc_sock *newsvsk; 750 int err, slen; 751 752 if (!sock) 753 return NULL; 754 755 clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 756 err = kernel_accept(sock, &newsock, O_NONBLOCK); 757 if (err < 0) { 758 if (err == -ENOMEM) 759 printk(KERN_WARNING "%s: no more sockets!\n", 760 serv->sv_name); 761 else if (err != -EAGAIN) 762 net_warn_ratelimited("%s: accept failed (err %d)!\n", 763 serv->sv_name, -err); 764 trace_svcsock_accept_err(xprt, serv->sv_name, err); 765 return NULL; 766 } 767 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 768 769 err = kernel_getpeername(newsock, sin); 770 if (err < 0) { 771 trace_svcsock_getpeername_err(xprt, serv->sv_name, err); 772 goto failed; /* aborted connection or whatever */ 773 } 774 slen = err; 775 776 /* Reset the inherited callbacks before calling svc_setup_socket */ 777 newsock->sk->sk_state_change = svsk->sk_ostate; 778 newsock->sk->sk_data_ready = svsk->sk_odata; 779 newsock->sk->sk_write_space = svsk->sk_owspace; 780 781 /* make sure that a write doesn't block forever when 782 * low on memory 783 */ 784 newsock->sk->sk_sndtimeo = HZ*30; 785 786 newsvsk = svc_setup_socket(serv, newsock, 787 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY)); 788 if (IS_ERR(newsvsk)) 789 goto failed; 790 svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen); 791 err = kernel_getsockname(newsock, sin); 792 slen = err; 793 if (unlikely(err < 0)) 794 slen = offsetof(struct sockaddr, sa_data); 795 svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen); 796 797 if (sock_is_loopback(newsock->sk)) 798 set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags); 799 else 800 clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags); 801 if (serv->sv_stats) 802 serv->sv_stats->nettcpconn++; 803 804 return &newsvsk->sk_xprt; 805 806 failed: 807 sock_release(newsock); 808 return NULL; 809 } 810 811 static size_t svc_tcp_restore_pages(struct svc_sock *svsk, 812 struct svc_rqst *rqstp) 813 { 814 size_t len = svsk->sk_datalen; 815 unsigned int i, npages; 816 817 if (!len) 818 return 0; 819 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 820 for (i = 0; i < npages; i++) { 821 if (rqstp->rq_pages[i] != NULL) 822 put_page(rqstp->rq_pages[i]); 823 BUG_ON(svsk->sk_pages[i] == NULL); 824 rqstp->rq_pages[i] = svsk->sk_pages[i]; 825 svsk->sk_pages[i] = NULL; 826 } 827 rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]); 828 return len; 829 } 830 831 static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp) 832 { 833 unsigned int i, len, npages; 834 835 if (svsk->sk_datalen == 0) 836 return; 837 len = svsk->sk_datalen; 838 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 839 for (i = 0; i < npages; i++) { 840 svsk->sk_pages[i] = rqstp->rq_pages[i]; 841 rqstp->rq_pages[i] = NULL; 842 } 843 } 844 845 static void svc_tcp_clear_pages(struct svc_sock *svsk) 846 { 847 unsigned int i, len, npages; 848 849 if (svsk->sk_datalen == 0) 850 goto out; 851 len = svsk->sk_datalen; 852 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; 853 for (i = 0; i < npages; i++) { 854 if (svsk->sk_pages[i] == NULL) { 855 WARN_ON_ONCE(1); 856 continue; 857 } 858 put_page(svsk->sk_pages[i]); 859 svsk->sk_pages[i] = NULL; 860 } 861 out: 862 svsk->sk_tcplen = 0; 863 svsk->sk_datalen = 0; 864 } 865 866 /* 867 * Receive fragment record header into sk_marker. 868 */ 869 static ssize_t svc_tcp_read_marker(struct svc_sock *svsk, 870 struct svc_rqst *rqstp) 871 { 872 ssize_t want, len; 873 874 /* If we haven't gotten the record length yet, 875 * get the next four bytes. 876 */ 877 if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) { 878 struct msghdr msg = { NULL }; 879 struct kvec iov; 880 881 want = sizeof(rpc_fraghdr) - svsk->sk_tcplen; 882 iov.iov_base = ((char *)&svsk->sk_marker) + svsk->sk_tcplen; 883 iov.iov_len = want; 884 iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, want); 885 len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT); 886 if (len < 0) 887 return len; 888 svsk->sk_tcplen += len; 889 if (len < want) { 890 /* call again to read the remaining bytes */ 891 goto err_short; 892 } 893 trace_svcsock_marker(&svsk->sk_xprt, svsk->sk_marker); 894 if (svc_sock_reclen(svsk) + svsk->sk_datalen > 895 svsk->sk_xprt.xpt_server->sv_max_mesg) 896 goto err_too_large; 897 } 898 return svc_sock_reclen(svsk); 899 900 err_too_large: 901 net_notice_ratelimited("svc: %s %s RPC fragment too large: %d\n", 902 __func__, svsk->sk_xprt.xpt_server->sv_name, 903 svc_sock_reclen(svsk)); 904 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 905 err_short: 906 return -EAGAIN; 907 } 908 909 static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp) 910 { 911 struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt; 912 struct rpc_rqst *req = NULL; 913 struct kvec *src, *dst; 914 __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base; 915 __be32 xid; 916 __be32 calldir; 917 918 xid = *p++; 919 calldir = *p; 920 921 if (!bc_xprt) 922 return -EAGAIN; 923 spin_lock(&bc_xprt->queue_lock); 924 req = xprt_lookup_rqst(bc_xprt, xid); 925 if (!req) 926 goto unlock_notfound; 927 928 memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf)); 929 /* 930 * XXX!: cheating for now! Only copying HEAD. 931 * But we know this is good enough for now (in fact, for any 932 * callback reply in the forseeable future). 933 */ 934 dst = &req->rq_private_buf.head[0]; 935 src = &rqstp->rq_arg.head[0]; 936 if (dst->iov_len < src->iov_len) 937 goto unlock_eagain; /* whatever; just giving up. */ 938 memcpy(dst->iov_base, src->iov_base, src->iov_len); 939 xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len); 940 rqstp->rq_arg.len = 0; 941 spin_unlock(&bc_xprt->queue_lock); 942 return 0; 943 unlock_notfound: 944 printk(KERN_NOTICE 945 "%s: Got unrecognized reply: " 946 "calldir 0x%x xpt_bc_xprt %p xid %08x\n", 947 __func__, ntohl(calldir), 948 bc_xprt, ntohl(xid)); 949 unlock_eagain: 950 spin_unlock(&bc_xprt->queue_lock); 951 return -EAGAIN; 952 } 953 954 static void svc_tcp_fragment_received(struct svc_sock *svsk) 955 { 956 /* If we have more data, signal svc_xprt_enqueue() to try again */ 957 svsk->sk_tcplen = 0; 958 svsk->sk_marker = xdr_zero; 959 } 960 961 /** 962 * svc_tcp_recvfrom - Receive data from a TCP socket 963 * @rqstp: request structure into which to receive an RPC Call 964 * 965 * Called in a loop when XPT_DATA has been set. 966 * 967 * Read the 4-byte stream record marker, then use the record length 968 * in that marker to set up exactly the resources needed to receive 969 * the next RPC message into @rqstp. 970 * 971 * Returns: 972 * On success, the number of bytes in a received RPC Call, or 973 * %0 if a complete RPC Call message was not ready to return 974 * 975 * The zero return case handles partial receives and callback Replies. 976 * The state of a partial receive is preserved in the svc_sock for 977 * the next call to svc_tcp_recvfrom. 978 */ 979 static int svc_tcp_recvfrom(struct svc_rqst *rqstp) 980 { 981 struct svc_sock *svsk = 982 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 983 struct svc_serv *serv = svsk->sk_xprt.xpt_server; 984 size_t want, base; 985 ssize_t len; 986 __be32 *p; 987 __be32 calldir; 988 989 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 990 len = svc_tcp_read_marker(svsk, rqstp); 991 if (len < 0) 992 goto error; 993 994 base = svc_tcp_restore_pages(svsk, rqstp); 995 want = len - (svsk->sk_tcplen - sizeof(rpc_fraghdr)); 996 len = svc_tcp_read_msg(rqstp, base + want, base); 997 if (len >= 0) { 998 trace_svcsock_tcp_recv(&svsk->sk_xprt, len); 999 svsk->sk_tcplen += len; 1000 svsk->sk_datalen += len; 1001 } 1002 if (len != want || !svc_sock_final_rec(svsk)) 1003 goto err_incomplete; 1004 if (svsk->sk_datalen < 8) 1005 goto err_nuts; 1006 1007 rqstp->rq_arg.len = svsk->sk_datalen; 1008 rqstp->rq_arg.page_base = 0; 1009 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) { 1010 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len; 1011 rqstp->rq_arg.page_len = 0; 1012 } else 1013 rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; 1014 1015 rqstp->rq_xprt_ctxt = NULL; 1016 rqstp->rq_prot = IPPROTO_TCP; 1017 if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags)) 1018 set_bit(RQ_LOCAL, &rqstp->rq_flags); 1019 else 1020 clear_bit(RQ_LOCAL, &rqstp->rq_flags); 1021 1022 p = (__be32 *)rqstp->rq_arg.head[0].iov_base; 1023 calldir = p[1]; 1024 if (calldir) 1025 len = receive_cb_reply(svsk, rqstp); 1026 1027 /* Reset TCP read info */ 1028 svsk->sk_datalen = 0; 1029 svc_tcp_fragment_received(svsk); 1030 1031 if (len < 0) 1032 goto error; 1033 1034 svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt); 1035 if (serv->sv_stats) 1036 serv->sv_stats->nettcpcnt++; 1037 1038 return rqstp->rq_arg.len; 1039 1040 err_incomplete: 1041 svc_tcp_save_pages(svsk, rqstp); 1042 if (len < 0 && len != -EAGAIN) 1043 goto err_delete; 1044 if (len == want) 1045 svc_tcp_fragment_received(svsk); 1046 else 1047 trace_svcsock_tcp_recv_short(&svsk->sk_xprt, 1048 svc_sock_reclen(svsk), 1049 svsk->sk_tcplen - sizeof(rpc_fraghdr)); 1050 goto err_noclose; 1051 error: 1052 if (len != -EAGAIN) 1053 goto err_delete; 1054 trace_svcsock_tcp_recv_eagain(&svsk->sk_xprt, 0); 1055 return 0; 1056 err_nuts: 1057 svsk->sk_datalen = 0; 1058 err_delete: 1059 trace_svcsock_tcp_recv_err(&svsk->sk_xprt, len); 1060 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 1061 err_noclose: 1062 return 0; /* record not complete */ 1063 } 1064 1065 /** 1066 * svc_tcp_sendto - Send out a reply on a TCP socket 1067 * @rqstp: completed svc_rqst 1068 * 1069 * xpt_mutex ensures @rqstp's whole message is written to the socket 1070 * without interruption. 1071 * 1072 * Returns the number of bytes sent, or a negative errno. 1073 */ 1074 static int svc_tcp_sendto(struct svc_rqst *rqstp) 1075 { 1076 struct svc_xprt *xprt = rqstp->rq_xprt; 1077 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1078 struct xdr_buf *xdr = &rqstp->rq_res; 1079 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | 1080 (u32)xdr->len); 1081 struct msghdr msg = { 1082 .msg_flags = 0, 1083 }; 1084 unsigned int sent; 1085 int err; 1086 1087 svc_tcp_release_rqst(rqstp); 1088 1089 mutex_lock(&xprt->xpt_mutex); 1090 if (svc_xprt_is_dead(xprt)) 1091 goto out_notconn; 1092 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, marker, &sent); 1093 xdr_free_bvec(xdr); 1094 trace_svcsock_tcp_send(xprt, err < 0 ? err : sent); 1095 if (err < 0 || sent != (xdr->len + sizeof(marker))) 1096 goto out_close; 1097 mutex_unlock(&xprt->xpt_mutex); 1098 return sent; 1099 1100 out_notconn: 1101 mutex_unlock(&xprt->xpt_mutex); 1102 return -ENOTCONN; 1103 out_close: 1104 pr_notice("rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n", 1105 xprt->xpt_server->sv_name, 1106 (err < 0) ? "got error" : "sent", 1107 (err < 0) ? err : sent, xdr->len); 1108 set_bit(XPT_CLOSE, &xprt->xpt_flags); 1109 svc_xprt_enqueue(xprt); 1110 mutex_unlock(&xprt->xpt_mutex); 1111 return -EAGAIN; 1112 } 1113 1114 static struct svc_xprt *svc_tcp_create(struct svc_serv *serv, 1115 struct net *net, 1116 struct sockaddr *sa, int salen, 1117 int flags) 1118 { 1119 return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags); 1120 } 1121 1122 static const struct svc_xprt_ops svc_tcp_ops = { 1123 .xpo_create = svc_tcp_create, 1124 .xpo_recvfrom = svc_tcp_recvfrom, 1125 .xpo_sendto = svc_tcp_sendto, 1126 .xpo_read_payload = svc_sock_read_payload, 1127 .xpo_release_rqst = svc_tcp_release_rqst, 1128 .xpo_detach = svc_tcp_sock_detach, 1129 .xpo_free = svc_sock_free, 1130 .xpo_has_wspace = svc_tcp_has_wspace, 1131 .xpo_accept = svc_tcp_accept, 1132 .xpo_secure_port = svc_sock_secure_port, 1133 .xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt, 1134 }; 1135 1136 static struct svc_xprt_class svc_tcp_class = { 1137 .xcl_name = "tcp", 1138 .xcl_owner = THIS_MODULE, 1139 .xcl_ops = &svc_tcp_ops, 1140 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, 1141 .xcl_ident = XPRT_TRANSPORT_TCP, 1142 }; 1143 1144 void svc_init_xprt_sock(void) 1145 { 1146 svc_reg_xprt_class(&svc_tcp_class); 1147 svc_reg_xprt_class(&svc_udp_class); 1148 } 1149 1150 void svc_cleanup_xprt_sock(void) 1151 { 1152 svc_unreg_xprt_class(&svc_tcp_class); 1153 svc_unreg_xprt_class(&svc_udp_class); 1154 } 1155 1156 static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv) 1157 { 1158 struct sock *sk = svsk->sk_sk; 1159 1160 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class, 1161 &svsk->sk_xprt, serv); 1162 set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags); 1163 set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags); 1164 if (sk->sk_state == TCP_LISTEN) { 1165 strcpy(svsk->sk_xprt.xpt_remotebuf, "listener"); 1166 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags); 1167 sk->sk_data_ready = svc_tcp_listen_data_ready; 1168 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags); 1169 } else { 1170 sk->sk_state_change = svc_tcp_state_change; 1171 sk->sk_data_ready = svc_data_ready; 1172 sk->sk_write_space = svc_write_space; 1173 1174 svsk->sk_marker = xdr_zero; 1175 svsk->sk_tcplen = 0; 1176 svsk->sk_datalen = 0; 1177 memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages)); 1178 1179 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; 1180 1181 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); 1182 switch (sk->sk_state) { 1183 case TCP_SYN_RECV: 1184 case TCP_ESTABLISHED: 1185 break; 1186 default: 1187 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags); 1188 } 1189 } 1190 } 1191 1192 void svc_sock_update_bufs(struct svc_serv *serv) 1193 { 1194 /* 1195 * The number of server threads has changed. Update 1196 * rcvbuf and sndbuf accordingly on all sockets 1197 */ 1198 struct svc_sock *svsk; 1199 1200 spin_lock_bh(&serv->sv_lock); 1201 list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) 1202 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); 1203 spin_unlock_bh(&serv->sv_lock); 1204 } 1205 EXPORT_SYMBOL_GPL(svc_sock_update_bufs); 1206 1207 /* 1208 * Initialize socket for RPC use and create svc_sock struct 1209 */ 1210 static struct svc_sock *svc_setup_socket(struct svc_serv *serv, 1211 struct socket *sock, 1212 int flags) 1213 { 1214 struct svc_sock *svsk; 1215 struct sock *inet; 1216 int pmap_register = !(flags & SVC_SOCK_ANONYMOUS); 1217 int err = 0; 1218 1219 svsk = kzalloc(sizeof(*svsk), GFP_KERNEL); 1220 if (!svsk) 1221 return ERR_PTR(-ENOMEM); 1222 1223 inet = sock->sk; 1224 1225 /* Register socket with portmapper */ 1226 if (pmap_register) 1227 err = svc_register(serv, sock_net(sock->sk), inet->sk_family, 1228 inet->sk_protocol, 1229 ntohs(inet_sk(inet)->inet_sport)); 1230 1231 if (err < 0) { 1232 kfree(svsk); 1233 return ERR_PTR(err); 1234 } 1235 1236 svsk->sk_sock = sock; 1237 svsk->sk_sk = inet; 1238 svsk->sk_ostate = inet->sk_state_change; 1239 svsk->sk_odata = inet->sk_data_ready; 1240 svsk->sk_owspace = inet->sk_write_space; 1241 /* 1242 * This barrier is necessary in order to prevent race condition 1243 * with svc_data_ready(), svc_listen_data_ready() and others 1244 * when calling callbacks above. 1245 */ 1246 wmb(); 1247 inet->sk_user_data = svsk; 1248 1249 /* Initialize the socket */ 1250 if (sock->type == SOCK_DGRAM) 1251 svc_udp_init(svsk, serv); 1252 else 1253 svc_tcp_init(svsk, serv); 1254 1255 trace_svcsock_new_socket(sock); 1256 return svsk; 1257 } 1258 1259 bool svc_alien_sock(struct net *net, int fd) 1260 { 1261 int err; 1262 struct socket *sock = sockfd_lookup(fd, &err); 1263 bool ret = false; 1264 1265 if (!sock) 1266 goto out; 1267 if (sock_net(sock->sk) != net) 1268 ret = true; 1269 sockfd_put(sock); 1270 out: 1271 return ret; 1272 } 1273 EXPORT_SYMBOL_GPL(svc_alien_sock); 1274 1275 /** 1276 * svc_addsock - add a listener socket to an RPC service 1277 * @serv: pointer to RPC service to which to add a new listener 1278 * @fd: file descriptor of the new listener 1279 * @name_return: pointer to buffer to fill in with name of listener 1280 * @len: size of the buffer 1281 * @cred: credential 1282 * 1283 * Fills in socket name and returns positive length of name if successful. 1284 * Name is terminated with '\n'. On error, returns a negative errno 1285 * value. 1286 */ 1287 int svc_addsock(struct svc_serv *serv, const int fd, char *name_return, 1288 const size_t len, const struct cred *cred) 1289 { 1290 int err = 0; 1291 struct socket *so = sockfd_lookup(fd, &err); 1292 struct svc_sock *svsk = NULL; 1293 struct sockaddr_storage addr; 1294 struct sockaddr *sin = (struct sockaddr *)&addr; 1295 int salen; 1296 1297 if (!so) 1298 return err; 1299 err = -EAFNOSUPPORT; 1300 if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6)) 1301 goto out; 1302 err = -EPROTONOSUPPORT; 1303 if (so->sk->sk_protocol != IPPROTO_TCP && 1304 so->sk->sk_protocol != IPPROTO_UDP) 1305 goto out; 1306 err = -EISCONN; 1307 if (so->state > SS_UNCONNECTED) 1308 goto out; 1309 err = -ENOENT; 1310 if (!try_module_get(THIS_MODULE)) 1311 goto out; 1312 svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS); 1313 if (IS_ERR(svsk)) { 1314 module_put(THIS_MODULE); 1315 err = PTR_ERR(svsk); 1316 goto out; 1317 } 1318 salen = kernel_getsockname(svsk->sk_sock, sin); 1319 if (salen >= 0) 1320 svc_xprt_set_local(&svsk->sk_xprt, sin, salen); 1321 svsk->sk_xprt.xpt_cred = get_cred(cred); 1322 svc_add_new_perm_xprt(serv, &svsk->sk_xprt); 1323 return svc_one_sock_name(svsk, name_return, len); 1324 out: 1325 sockfd_put(so); 1326 return err; 1327 } 1328 EXPORT_SYMBOL_GPL(svc_addsock); 1329 1330 /* 1331 * Create socket for RPC service. 1332 */ 1333 static struct svc_xprt *svc_create_socket(struct svc_serv *serv, 1334 int protocol, 1335 struct net *net, 1336 struct sockaddr *sin, int len, 1337 int flags) 1338 { 1339 struct svc_sock *svsk; 1340 struct socket *sock; 1341 int error; 1342 int type; 1343 struct sockaddr_storage addr; 1344 struct sockaddr *newsin = (struct sockaddr *)&addr; 1345 int newlen; 1346 int family; 1347 1348 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) { 1349 printk(KERN_WARNING "svc: only UDP and TCP " 1350 "sockets supported\n"); 1351 return ERR_PTR(-EINVAL); 1352 } 1353 1354 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM; 1355 switch (sin->sa_family) { 1356 case AF_INET6: 1357 family = PF_INET6; 1358 break; 1359 case AF_INET: 1360 family = PF_INET; 1361 break; 1362 default: 1363 return ERR_PTR(-EINVAL); 1364 } 1365 1366 error = __sock_create(net, family, type, protocol, &sock, 1); 1367 if (error < 0) 1368 return ERR_PTR(error); 1369 1370 svc_reclassify_socket(sock); 1371 1372 /* 1373 * If this is an PF_INET6 listener, we want to avoid 1374 * getting requests from IPv4 remotes. Those should 1375 * be shunted to a PF_INET listener via rpcbind. 1376 */ 1377 if (family == PF_INET6) 1378 ip6_sock_set_v6only(sock->sk); 1379 if (type == SOCK_STREAM) 1380 sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */ 1381 error = kernel_bind(sock, sin, len); 1382 if (error < 0) 1383 goto bummer; 1384 1385 error = kernel_getsockname(sock, newsin); 1386 if (error < 0) 1387 goto bummer; 1388 newlen = error; 1389 1390 if (protocol == IPPROTO_TCP) { 1391 if ((error = kernel_listen(sock, 64)) < 0) 1392 goto bummer; 1393 } 1394 1395 svsk = svc_setup_socket(serv, sock, flags); 1396 if (IS_ERR(svsk)) { 1397 error = PTR_ERR(svsk); 1398 goto bummer; 1399 } 1400 svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen); 1401 return (struct svc_xprt *)svsk; 1402 bummer: 1403 sock_release(sock); 1404 return ERR_PTR(error); 1405 } 1406 1407 /* 1408 * Detach the svc_sock from the socket so that no 1409 * more callbacks occur. 1410 */ 1411 static void svc_sock_detach(struct svc_xprt *xprt) 1412 { 1413 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1414 struct sock *sk = svsk->sk_sk; 1415 1416 /* put back the old socket callbacks */ 1417 lock_sock(sk); 1418 sk->sk_state_change = svsk->sk_ostate; 1419 sk->sk_data_ready = svsk->sk_odata; 1420 sk->sk_write_space = svsk->sk_owspace; 1421 sk->sk_user_data = NULL; 1422 release_sock(sk); 1423 } 1424 1425 /* 1426 * Disconnect the socket, and reset the callbacks 1427 */ 1428 static void svc_tcp_sock_detach(struct svc_xprt *xprt) 1429 { 1430 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1431 1432 svc_sock_detach(xprt); 1433 1434 if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) { 1435 svc_tcp_clear_pages(svsk); 1436 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR); 1437 } 1438 } 1439 1440 /* 1441 * Free the svc_sock's socket resources and the svc_sock itself. 1442 */ 1443 static void svc_sock_free(struct svc_xprt *xprt) 1444 { 1445 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); 1446 1447 if (svsk->sk_sock->file) 1448 sockfd_put(svsk->sk_sock); 1449 else 1450 sock_release(svsk->sk_sock); 1451 kfree(svsk); 1452 } 1453