Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
17926a79 DH |
2 | /* RxRPC recvmsg() implementation |
3 | * | |
4 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
5 | * Written by David Howells (dhowells@redhat.com) | |
17926a79 DH |
6 | */ |
7 | ||
9b6d5398 JP |
8 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
9 | ||
17926a79 DH |
10 | #include <linux/net.h> |
11 | #include <linux/skbuff.h> | |
bc3b2d7f | 12 | #include <linux/export.h> |
174cd4b1 IM |
13 | #include <linux/sched/signal.h> |
14 | ||
17926a79 DH |
15 | #include <net/sock.h> |
16 | #include <net/af_rxrpc.h> | |
17 | #include "ar-internal.h" | |
18 | ||
17926a79 | 19 | /* |
248f219c DH |
20 | * Post a call for attention by the socket or kernel service. Further |
21 | * notifications are suppressed by putting recvmsg_link on a dummy queue. | |
17926a79 | 22 | */ |
248f219c | 23 | void rxrpc_notify_socket(struct rxrpc_call *call) |
17926a79 | 24 | { |
248f219c DH |
25 | struct rxrpc_sock *rx; |
26 | struct sock *sk; | |
17926a79 | 27 | |
248f219c | 28 | _enter("%d", call->debug_id); |
17926a79 | 29 | |
248f219c DH |
30 | if (!list_empty(&call->recvmsg_link)) |
31 | return; | |
32 | ||
33 | rcu_read_lock(); | |
34 | ||
35 | rx = rcu_dereference(call->socket); | |
36 | sk = &rx->sk; | |
37 | if (rx && sk->sk_state < RXRPC_CLOSE) { | |
38 | if (call->notify_rx) { | |
20acbd9a | 39 | spin_lock_bh(&call->notify_lock); |
248f219c | 40 | call->notify_rx(sk, call, call->user_call_ID); |
20acbd9a | 41 | spin_unlock_bh(&call->notify_lock); |
248f219c DH |
42 | } else { |
43 | write_lock_bh(&rx->recvmsg_lock); | |
44 | if (list_empty(&call->recvmsg_link)) { | |
45 | rxrpc_get_call(call, rxrpc_call_got); | |
46 | list_add_tail(&call->recvmsg_link, &rx->recvmsg_q); | |
47 | } | |
48 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 49 | |
248f219c DH |
50 | if (!sock_flag(sk, SOCK_DEAD)) { |
51 | _debug("call %ps", sk->sk_data_ready); | |
52 | sk->sk_data_ready(sk); | |
53 | } | |
54 | } | |
55 | } | |
17926a79 | 56 | |
248f219c DH |
57 | rcu_read_unlock(); |
58 | _leave(""); | |
59 | } | |
17926a79 | 60 | |
248f219c DH |
61 | /* |
62 | * Pass a call terminating message to userspace. | |
63 | */ | |
64 | static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg) | |
65 | { | |
66 | u32 tmp = 0; | |
67 | int ret; | |
17926a79 | 68 | |
248f219c DH |
69 | switch (call->completion) { |
70 | case RXRPC_CALL_SUCCEEDED: | |
71 | ret = 0; | |
72 | if (rxrpc_is_service_call(call)) | |
73 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &tmp); | |
74 | break; | |
75 | case RXRPC_CALL_REMOTELY_ABORTED: | |
76 | tmp = call->abort_code; | |
77 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
78 | break; | |
79 | case RXRPC_CALL_LOCALLY_ABORTED: | |
80 | tmp = call->abort_code; | |
81 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
82 | break; | |
83 | case RXRPC_CALL_NETWORK_ERROR: | |
3a92789a | 84 | tmp = -call->error; |
248f219c DH |
85 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &tmp); |
86 | break; | |
87 | case RXRPC_CALL_LOCAL_ERROR: | |
3a92789a | 88 | tmp = -call->error; |
248f219c DH |
89 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4, &tmp); |
90 | break; | |
91 | default: | |
92 | pr_err("Invalid terminal call state %u\n", call->state); | |
93 | BUG(); | |
94 | break; | |
95 | } | |
17926a79 | 96 | |
84997905 DH |
97 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_terminal, call->rx_hard_ack, |
98 | call->rx_pkt_offset, call->rx_pkt_len, ret); | |
248f219c DH |
99 | return ret; |
100 | } | |
17926a79 | 101 | |
248f219c DH |
102 | /* |
103 | * Pass back notification of a new call. The call is added to the | |
104 | * to-be-accepted list. This means that the next call to be accepted might not | |
105 | * be the last call seen awaiting acceptance, but unless we leave this on the | |
106 | * front of the queue and block all other messages until someone gives us a | |
107 | * user_ID for it, there's not a lot we can do. | |
108 | */ | |
109 | static int rxrpc_recvmsg_new_call(struct rxrpc_sock *rx, | |
110 | struct rxrpc_call *call, | |
111 | struct msghdr *msg, int flags) | |
112 | { | |
113 | int tmp = 0, ret; | |
17926a79 | 114 | |
248f219c | 115 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &tmp); |
17926a79 | 116 | |
248f219c DH |
117 | if (ret == 0 && !(flags & MSG_PEEK)) { |
118 | _debug("to be accepted"); | |
119 | write_lock_bh(&rx->recvmsg_lock); | |
120 | list_del_init(&call->recvmsg_link); | |
121 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 122 | |
3432a757 | 123 | rxrpc_get_call(call, rxrpc_call_got); |
248f219c DH |
124 | write_lock(&rx->call_lock); |
125 | list_add_tail(&call->accept_link, &rx->to_be_accepted); | |
126 | write_unlock(&rx->call_lock); | |
127 | } | |
17926a79 | 128 | |
84997905 | 129 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_to_be_accepted, 1, 0, 0, ret); |
248f219c DH |
130 | return ret; |
131 | } | |
17926a79 | 132 | |
248f219c DH |
133 | /* |
134 | * End the packet reception phase. | |
135 | */ | |
b69d94d7 | 136 | static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) |
248f219c DH |
137 | { |
138 | _enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]); | |
17926a79 | 139 | |
58dc63c9 | 140 | trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); |
816c9fce DH |
141 | ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); |
142 | ||
248f219c | 143 | if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { |
e8c3af6b | 144 | rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, serial, false, true, |
9c7ad434 | 145 | rxrpc_propose_ack_terminal_ack); |
a71a2651 | 146 | //rxrpc_send_ack_packet(call, false, NULL); |
248f219c | 147 | } |
17926a79 | 148 | |
248f219c | 149 | write_lock_bh(&call->state_lock); |
17926a79 | 150 | |
248f219c DH |
151 | switch (call->state) { |
152 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
153 | __rxrpc_call_completed(call); | |
9749fd2b | 154 | write_unlock_bh(&call->state_lock); |
248f219c | 155 | break; |
17926a79 | 156 | |
248f219c | 157 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
71f3ca40 | 158 | call->tx_phase = true; |
248f219c | 159 | call->state = RXRPC_CALL_SERVER_ACK_REQUEST; |
a158bdd3 | 160 | call->expect_req_by = jiffies + MAX_JIFFY_OFFSET; |
9749fd2b | 161 | write_unlock_bh(&call->state_lock); |
e8c3af6b | 162 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial, false, true, |
9749fd2b | 163 | rxrpc_propose_ack_processing_op); |
248f219c DH |
164 | break; |
165 | default: | |
9749fd2b | 166 | write_unlock_bh(&call->state_lock); |
248f219c DH |
167 | break; |
168 | } | |
248f219c | 169 | } |
17926a79 | 170 | |
248f219c DH |
171 | /* |
172 | * Discard a packet we've used up and advance the Rx window by one. | |
173 | */ | |
174 | static void rxrpc_rotate_rx_window(struct rxrpc_call *call) | |
175 | { | |
816c9fce | 176 | struct rxrpc_skb_priv *sp; |
248f219c | 177 | struct sk_buff *skb; |
58dc63c9 | 178 | rxrpc_serial_t serial; |
248f219c | 179 | rxrpc_seq_t hard_ack, top; |
e2de6c40 DH |
180 | bool last = false; |
181 | u8 subpacket; | |
248f219c DH |
182 | int ix; |
183 | ||
184 | _enter("%d", call->debug_id); | |
185 | ||
186 | hard_ack = call->rx_hard_ack; | |
187 | top = smp_load_acquire(&call->rx_top); | |
188 | ASSERT(before(hard_ack, top)); | |
189 | ||
190 | hard_ack++; | |
191 | ix = hard_ack & RXRPC_RXTX_BUFF_MASK; | |
192 | skb = call->rxtx_buffer[ix]; | |
987db9f7 | 193 | rxrpc_see_skb(skb, rxrpc_skb_rotated); |
816c9fce | 194 | sp = rxrpc_skb(skb); |
e2de6c40 DH |
195 | |
196 | subpacket = call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET; | |
197 | serial = sp->hdr.serial + subpacket; | |
198 | ||
199 | if (subpacket == sp->nr_subpackets - 1 && | |
200 | sp->rx_flags & RXRPC_SKB_INCL_LAST) | |
201 | last = true; | |
58dc63c9 | 202 | |
248f219c DH |
203 | call->rxtx_buffer[ix] = NULL; |
204 | call->rxtx_annotations[ix] = 0; | |
205 | /* Barrier against rxrpc_input_data(). */ | |
206 | smp_store_release(&call->rx_hard_ack, hard_ack); | |
17926a79 | 207 | |
987db9f7 | 208 | rxrpc_free_skb(skb, rxrpc_skb_freed); |
17926a79 | 209 | |
58dc63c9 | 210 | trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); |
e2de6c40 | 211 | if (last) { |
b69d94d7 | 212 | rxrpc_end_rx_phase(call, serial); |
805b21b9 DH |
213 | } else { |
214 | /* Check to see if there's an ACK that needs sending. */ | |
215 | if (after_eq(hard_ack, call->ackr_consumed + 2) || | |
216 | after_eq(top, call->ackr_seen + 2) || | |
217 | (hard_ack == top && after(hard_ack, call->ackr_consumed))) | |
e8c3af6b | 218 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial, |
8637abaa | 219 | true, true, |
805b21b9 | 220 | rxrpc_propose_ack_rotate_rx); |
8637abaa | 221 | if (call->ackr_reason && call->ackr_reason != RXRPC_ACK_DELAY) |
bd1fdf8c | 222 | rxrpc_send_ack_packet(call, false, NULL); |
805b21b9 | 223 | } |
248f219c DH |
224 | } |
225 | ||
226 | /* | |
227 | * Decrypt and verify a (sub)packet. The packet's length may be changed due to | |
228 | * padding, but if this is the case, the packet length will be resident in the | |
229 | * socket buffer. Note that we can't modify the master skb info as the skb may | |
230 | * be the home to multiple subpackets. | |
231 | */ | |
232 | static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb, | |
233 | u8 annotation, | |
234 | unsigned int offset, unsigned int len) | |
235 | { | |
236 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
237 | rxrpc_seq_t seq = sp->hdr.seq; | |
238 | u16 cksum = sp->hdr.cksum; | |
e2de6c40 | 239 | u8 subpacket = annotation & RXRPC_RX_ANNO_SUBPACKET; |
248f219c DH |
240 | |
241 | _enter(""); | |
242 | ||
243 | /* For all but the head jumbo subpacket, the security checksum is in a | |
244 | * jumbo header immediately prior to the data. | |
245 | */ | |
e2de6c40 | 246 | if (subpacket > 0) { |
248f219c DH |
247 | __be16 tmp; |
248 | if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0) | |
249 | BUG(); | |
250 | cksum = ntohs(tmp); | |
e2de6c40 | 251 | seq += subpacket; |
248f219c DH |
252 | } |
253 | ||
254 | return call->conn->security->verify_packet(call, skb, offset, len, | |
255 | seq, cksum); | |
256 | } | |
257 | ||
258 | /* | |
259 | * Locate the data within a packet. This is complicated by: | |
260 | * | |
261 | * (1) An skb may contain a jumbo packet - so we have to find the appropriate | |
262 | * subpacket. | |
263 | * | |
264 | * (2) The (sub)packets may be encrypted and, if so, the encrypted portion | |
265 | * contains an extra header which includes the true length of the data, | |
266 | * excluding any encrypted padding. | |
267 | */ | |
268 | static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb, | |
269 | u8 *_annotation, | |
270 | unsigned int *_offset, unsigned int *_len) | |
271 | { | |
e2de6c40 | 272 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
775e5b71 | 273 | unsigned int offset = sizeof(struct rxrpc_wire_header); |
650b4eca | 274 | unsigned int len; |
248f219c DH |
275 | int ret; |
276 | u8 annotation = *_annotation; | |
e2de6c40 | 277 | u8 subpacket = annotation & RXRPC_RX_ANNO_SUBPACKET; |
248f219c | 278 | |
248f219c | 279 | /* Locate the subpacket */ |
e2de6c40 | 280 | offset += subpacket * RXRPC_JUMBO_SUBPKTLEN; |
775e5b71 | 281 | len = skb->len - offset; |
e2de6c40 DH |
282 | if (subpacket < sp->nr_subpackets - 1) |
283 | len = RXRPC_JUMBO_DATALEN; | |
248f219c DH |
284 | |
285 | if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) { | |
286 | ret = rxrpc_verify_packet(call, skb, annotation, offset, len); | |
17926a79 | 287 | if (ret < 0) |
248f219c DH |
288 | return ret; |
289 | *_annotation |= RXRPC_RX_ANNO_VERIFIED; | |
290 | } | |
17926a79 | 291 | |
248f219c DH |
292 | *_offset = offset; |
293 | *_len = len; | |
294 | call->conn->security->locate_data(call, skb, _offset, _len); | |
295 | return 0; | |
296 | } | |
17926a79 | 297 | |
248f219c DH |
298 | /* |
299 | * Deliver messages to a call. This keeps processing packets until the buffer | |
300 | * is filled and we find either more DATA (returns 0) or the end of the DATA | |
301 | * (returns 1). If more packets are required, it returns -EAGAIN. | |
302 | */ | |
303 | static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call, | |
304 | struct msghdr *msg, struct iov_iter *iter, | |
305 | size_t len, int flags, size_t *_offset) | |
306 | { | |
307 | struct rxrpc_skb_priv *sp; | |
308 | struct sk_buff *skb; | |
e2de6c40 | 309 | rxrpc_serial_t serial; |
248f219c DH |
310 | rxrpc_seq_t hard_ack, top, seq; |
311 | size_t remain; | |
312 | bool last; | |
313 | unsigned int rx_pkt_offset, rx_pkt_len; | |
816c9fce | 314 | int ix, copy, ret = -EAGAIN, ret2; |
248f219c | 315 | |
d0b35a42 DH |
316 | if (test_and_clear_bit(RXRPC_CALL_RX_UNDERRUN, &call->flags) && |
317 | call->ackr_reason) | |
318 | rxrpc_send_ack_packet(call, false, NULL); | |
319 | ||
248f219c DH |
320 | rx_pkt_offset = call->rx_pkt_offset; |
321 | rx_pkt_len = call->rx_pkt_len; | |
322 | ||
816c9fce DH |
323 | if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) { |
324 | seq = call->rx_hard_ack; | |
325 | ret = 1; | |
326 | goto done; | |
327 | } | |
328 | ||
248f219c DH |
329 | /* Barriers against rxrpc_input_data(). */ |
330 | hard_ack = call->rx_hard_ack; | |
d7e15835 DH |
331 | seq = hard_ack + 1; |
332 | while (top = smp_load_acquire(&call->rx_top), | |
333 | before_eq(seq, top) | |
334 | ) { | |
248f219c DH |
335 | ix = seq & RXRPC_RXTX_BUFF_MASK; |
336 | skb = call->rxtx_buffer[ix]; | |
84997905 DH |
337 | if (!skb) { |
338 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq, | |
339 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 340 | break; |
84997905 | 341 | } |
248f219c | 342 | smp_rmb(); |
987db9f7 | 343 | rxrpc_see_skb(skb, rxrpc_skb_seen); |
248f219c | 344 | sp = rxrpc_skb(skb); |
17926a79 | 345 | |
e2de6c40 DH |
346 | if (!(flags & MSG_PEEK)) { |
347 | serial = sp->hdr.serial; | |
348 | serial += call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET; | |
58dc63c9 | 349 | trace_rxrpc_receive(call, rxrpc_receive_front, |
e2de6c40 DH |
350 | serial, seq); |
351 | } | |
58dc63c9 | 352 | |
248f219c DH |
353 | if (msg) |
354 | sock_recv_timestamp(msg, sock->sk, skb); | |
355 | ||
2e2ea51d | 356 | if (rx_pkt_offset == 0) { |
816c9fce DH |
357 | ret2 = rxrpc_locate_data(call, skb, |
358 | &call->rxtx_annotations[ix], | |
359 | &rx_pkt_offset, &rx_pkt_len); | |
84997905 DH |
360 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq, |
361 | rx_pkt_offset, rx_pkt_len, ret2); | |
816c9fce DH |
362 | if (ret2 < 0) { |
363 | ret = ret2; | |
2e2ea51d | 364 | goto out; |
816c9fce | 365 | } |
84997905 DH |
366 | } else { |
367 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq, | |
368 | rx_pkt_offset, rx_pkt_len, 0); | |
2e2ea51d | 369 | } |
248f219c DH |
370 | |
371 | /* We have to handle short, empty and used-up DATA packets. */ | |
372 | remain = len - *_offset; | |
373 | copy = rx_pkt_len; | |
374 | if (copy > remain) | |
375 | copy = remain; | |
376 | if (copy > 0) { | |
816c9fce DH |
377 | ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter, |
378 | copy); | |
379 | if (ret2 < 0) { | |
380 | ret = ret2; | |
248f219c | 381 | goto out; |
816c9fce | 382 | } |
248f219c DH |
383 | |
384 | /* handle piecemeal consumption of data packets */ | |
248f219c DH |
385 | rx_pkt_offset += copy; |
386 | rx_pkt_len -= copy; | |
387 | *_offset += copy; | |
388 | } | |
17926a79 | 389 | |
248f219c | 390 | if (rx_pkt_len > 0) { |
84997905 DH |
391 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq, |
392 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 393 | ASSERTCMP(*_offset, ==, len); |
816c9fce | 394 | ret = 0; |
17926a79 DH |
395 | break; |
396 | } | |
397 | ||
248f219c DH |
398 | /* The whole packet has been transferred. */ |
399 | last = sp->hdr.flags & RXRPC_LAST_PACKET; | |
372ee163 | 400 | if (!(flags & MSG_PEEK)) |
248f219c DH |
401 | rxrpc_rotate_rx_window(call); |
402 | rx_pkt_offset = 0; | |
403 | rx_pkt_len = 0; | |
17926a79 | 404 | |
816c9fce DH |
405 | if (last) { |
406 | ASSERTCMP(seq, ==, READ_ONCE(call->rx_top)); | |
248f219c | 407 | ret = 1; |
816c9fce DH |
408 | goto out; |
409 | } | |
d7e15835 DH |
410 | |
411 | seq++; | |
248f219c | 412 | } |
816c9fce | 413 | |
248f219c DH |
414 | out: |
415 | if (!(flags & MSG_PEEK)) { | |
416 | call->rx_pkt_offset = rx_pkt_offset; | |
417 | call->rx_pkt_len = rx_pkt_len; | |
418 | } | |
816c9fce | 419 | done: |
84997905 DH |
420 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq, |
421 | rx_pkt_offset, rx_pkt_len, ret); | |
d0b35a42 DH |
422 | if (ret == -EAGAIN) |
423 | set_bit(RXRPC_CALL_RX_UNDERRUN, &call->flags); | |
248f219c DH |
424 | return ret; |
425 | } | |
17926a79 | 426 | |
248f219c DH |
427 | /* |
428 | * Receive a message from an RxRPC socket | |
429 | * - we need to be careful about two or more threads calling recvmsg | |
430 | * simultaneously | |
431 | */ | |
432 | int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, | |
433 | int flags) | |
434 | { | |
435 | struct rxrpc_call *call; | |
436 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); | |
437 | struct list_head *l; | |
438 | size_t copied = 0; | |
439 | long timeo; | |
440 | int ret; | |
441 | ||
442 | DEFINE_WAIT(wait); | |
443 | ||
84997905 | 444 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0); |
248f219c DH |
445 | |
446 | if (flags & (MSG_OOB | MSG_TRUNC)) | |
447 | return -EOPNOTSUPP; | |
448 | ||
449 | timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); | |
450 | ||
451 | try_again: | |
452 | lock_sock(&rx->sk); | |
453 | ||
454 | /* Return immediately if a client socket has no outstanding calls */ | |
455 | if (RB_EMPTY_ROOT(&rx->calls) && | |
456 | list_empty(&rx->recvmsg_q) && | |
457 | rx->sk.sk_state != RXRPC_SERVER_LISTENING) { | |
458 | release_sock(&rx->sk); | |
459 | return -ENODATA; | |
17926a79 DH |
460 | } |
461 | ||
248f219c DH |
462 | if (list_empty(&rx->recvmsg_q)) { |
463 | ret = -EWOULDBLOCK; | |
84997905 DH |
464 | if (timeo == 0) { |
465 | call = NULL; | |
248f219c | 466 | goto error_no_call; |
84997905 | 467 | } |
248f219c DH |
468 | |
469 | release_sock(&rx->sk); | |
470 | ||
471 | /* Wait for something to happen */ | |
472 | prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, | |
473 | TASK_INTERRUPTIBLE); | |
474 | ret = sock_error(&rx->sk); | |
475 | if (ret) | |
476 | goto wait_error; | |
477 | ||
478 | if (list_empty(&rx->recvmsg_q)) { | |
479 | if (signal_pending(current)) | |
480 | goto wait_interrupted; | |
84997905 DH |
481 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, |
482 | 0, 0, 0, 0); | |
248f219c | 483 | timeo = schedule_timeout(timeo); |
17926a79 | 484 | } |
248f219c DH |
485 | finish_wait(sk_sleep(&rx->sk), &wait); |
486 | goto try_again; | |
17926a79 DH |
487 | } |
488 | ||
248f219c DH |
489 | /* Find the next call and dequeue it if we're not just peeking. If we |
490 | * do dequeue it, that comes with a ref that we will need to release. | |
491 | */ | |
492 | write_lock_bh(&rx->recvmsg_lock); | |
493 | l = rx->recvmsg_q.next; | |
494 | call = list_entry(l, struct rxrpc_call, recvmsg_link); | |
495 | if (!(flags & MSG_PEEK)) | |
496 | list_del_init(&call->recvmsg_link); | |
497 | else | |
498 | rxrpc_get_call(call, rxrpc_call_got); | |
499 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 500 | |
84997905 | 501 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0); |
248f219c | 502 | |
540b1c48 DH |
503 | /* We're going to drop the socket lock, so we need to lock the call |
504 | * against interference by sendmsg. | |
505 | */ | |
506 | if (!mutex_trylock(&call->user_mutex)) { | |
507 | ret = -EWOULDBLOCK; | |
508 | if (flags & MSG_DONTWAIT) | |
509 | goto error_requeue_call; | |
510 | ret = -ERESTARTSYS; | |
511 | if (mutex_lock_interruptible(&call->user_mutex) < 0) | |
512 | goto error_requeue_call; | |
513 | } | |
514 | ||
515 | release_sock(&rx->sk); | |
516 | ||
248f219c | 517 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) |
17926a79 | 518 | BUG(); |
248f219c DH |
519 | |
520 | if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { | |
521 | if (flags & MSG_CMSG_COMPAT) { | |
522 | unsigned int id32 = call->user_call_ID; | |
523 | ||
524 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
525 | sizeof(unsigned int), &id32); | |
526 | } else { | |
a16b8d0c DH |
527 | unsigned long idl = call->user_call_ID; |
528 | ||
248f219c | 529 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, |
a16b8d0c | 530 | sizeof(unsigned long), &idl); |
f5c17aae | 531 | } |
248f219c | 532 | if (ret < 0) |
540b1c48 | 533 | goto error_unlock_call; |
248f219c DH |
534 | } |
535 | ||
536 | if (msg->msg_name) { | |
68d6d1ae DH |
537 | struct sockaddr_rxrpc *srx = msg->msg_name; |
538 | size_t len = sizeof(call->peer->srx); | |
539 | ||
540 | memcpy(msg->msg_name, &call->peer->srx, len); | |
541 | srx->srx_service = call->service_id; | |
248f219c DH |
542 | msg->msg_namelen = len; |
543 | } | |
544 | ||
146d8fef | 545 | switch (READ_ONCE(call->state)) { |
248f219c DH |
546 | case RXRPC_CALL_SERVER_ACCEPTING: |
547 | ret = rxrpc_recvmsg_new_call(rx, call, msg, flags); | |
17926a79 | 548 | break; |
248f219c DH |
549 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
550 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
551 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
552 | ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len, | |
553 | flags, &copied); | |
554 | if (ret == -EAGAIN) | |
555 | ret = 0; | |
33b603fd DH |
556 | |
557 | if (after(call->rx_top, call->rx_hard_ack) && | |
558 | call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK]) | |
559 | rxrpc_notify_socket(call); | |
17926a79 DH |
560 | break; |
561 | default: | |
248f219c | 562 | ret = 0; |
17926a79 DH |
563 | break; |
564 | } | |
565 | ||
566 | if (ret < 0) | |
540b1c48 | 567 | goto error_unlock_call; |
17926a79 | 568 | |
248f219c DH |
569 | if (call->state == RXRPC_CALL_COMPLETE) { |
570 | ret = rxrpc_recvmsg_term(call, msg); | |
571 | if (ret < 0) | |
540b1c48 | 572 | goto error_unlock_call; |
248f219c DH |
573 | if (!(flags & MSG_PEEK)) |
574 | rxrpc_release_call(rx, call); | |
575 | msg->msg_flags |= MSG_EOR; | |
576 | ret = 1; | |
17926a79 DH |
577 | } |
578 | ||
248f219c DH |
579 | if (ret == 0) |
580 | msg->msg_flags |= MSG_MORE; | |
581 | else | |
582 | msg->msg_flags &= ~MSG_MORE; | |
583 | ret = copied; | |
17926a79 | 584 | |
540b1c48 DH |
585 | error_unlock_call: |
586 | mutex_unlock(&call->user_mutex); | |
fff72429 | 587 | rxrpc_put_call(call, rxrpc_call_put); |
540b1c48 DH |
588 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
589 | return ret; | |
590 | ||
591 | error_requeue_call: | |
592 | if (!(flags & MSG_PEEK)) { | |
593 | write_lock_bh(&rx->recvmsg_lock); | |
594 | list_add(&call->recvmsg_link, &rx->recvmsg_q); | |
595 | write_unlock_bh(&rx->recvmsg_lock); | |
596 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_requeue, 0, 0, 0, 0); | |
597 | } else { | |
598 | rxrpc_put_call(call, rxrpc_call_put); | |
599 | } | |
248f219c DH |
600 | error_no_call: |
601 | release_sock(&rx->sk); | |
6dce3c20 | 602 | error_trace: |
84997905 | 603 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
17926a79 DH |
604 | return ret; |
605 | ||
17926a79 DH |
606 | wait_interrupted: |
607 | ret = sock_intr_errno(timeo); | |
608 | wait_error: | |
4a4771a5 | 609 | finish_wait(sk_sleep(&rx->sk), &wait); |
84997905 | 610 | call = NULL; |
6dce3c20 | 611 | goto error_trace; |
d001648e | 612 | } |
651350d1 DH |
613 | |
614 | /** | |
d001648e DH |
615 | * rxrpc_kernel_recv_data - Allow a kernel service to receive data/info |
616 | * @sock: The socket that the call exists on | |
617 | * @call: The call to send data through | |
eb9950eb | 618 | * @iter: The buffer to receive into |
d001648e DH |
619 | * @want_more: True if more data is expected to be read |
620 | * @_abort: Where the abort code is stored if -ECONNABORTED is returned | |
a68f4a27 | 621 | * @_service: Where to store the actual service ID (may be upgraded) |
d001648e DH |
622 | * |
623 | * Allow a kernel service to receive data and pick up information about the | |
624 | * state of a call. Returns 0 if got what was asked for and there's more | |
625 | * available, 1 if we got what was asked for and we're at the end of the data | |
626 | * and -EAGAIN if we need more data. | |
627 | * | |
628 | * Note that we may return -EAGAIN to drain empty packets at the end of the | |
629 | * data, even if we've already copied over the requested data. | |
651350d1 | 630 | * |
d001648e | 631 | * *_abort should also be initialised to 0. |
651350d1 | 632 | */ |
d001648e | 633 | int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call, |
eb9950eb | 634 | struct iov_iter *iter, |
a68f4a27 | 635 | bool want_more, u32 *_abort, u16 *_service) |
651350d1 | 636 | { |
eb9950eb | 637 | size_t offset = 0; |
d001648e | 638 | int ret; |
651350d1 | 639 | |
eb9950eb | 640 | _enter("{%d,%s},%zu,%d", |
248f219c | 641 | call->debug_id, rxrpc_call_states[call->state], |
eb9950eb | 642 | iov_iter_count(iter), want_more); |
d001648e | 643 | |
d001648e | 644 | ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING); |
651350d1 | 645 | |
540b1c48 | 646 | mutex_lock(&call->user_mutex); |
d001648e | 647 | |
146d8fef | 648 | switch (READ_ONCE(call->state)) { |
d001648e DH |
649 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
650 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
651 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
eb9950eb DH |
652 | ret = rxrpc_recvmsg_data(sock, call, NULL, iter, |
653 | iov_iter_count(iter), 0, | |
654 | &offset); | |
d001648e DH |
655 | if (ret < 0) |
656 | goto out; | |
657 | ||
658 | /* We can only reach here with a partially full buffer if we | |
659 | * have reached the end of the data. We must otherwise have a | |
660 | * full buffer or have been given -EAGAIN. | |
661 | */ | |
662 | if (ret == 1) { | |
eb9950eb | 663 | if (iov_iter_count(iter) > 0) |
d001648e DH |
664 | goto short_data; |
665 | if (!want_more) | |
666 | goto read_phase_complete; | |
667 | ret = 0; | |
668 | goto out; | |
669 | } | |
670 | ||
671 | if (!want_more) | |
672 | goto excess_data; | |
673 | goto out; | |
674 | ||
675 | case RXRPC_CALL_COMPLETE: | |
676 | goto call_complete; | |
677 | ||
678 | default: | |
d001648e DH |
679 | ret = -EINPROGRESS; |
680 | goto out; | |
681 | } | |
682 | ||
683 | read_phase_complete: | |
684 | ret = 1; | |
685 | out: | |
d0b35a42 DH |
686 | switch (call->ackr_reason) { |
687 | case RXRPC_ACK_IDLE: | |
688 | break; | |
689 | case RXRPC_ACK_DELAY: | |
690 | if (ret != -EAGAIN) | |
691 | break; | |
692 | /* Fall through */ | |
693 | default: | |
694 | rxrpc_send_ack_packet(call, false, NULL); | |
695 | } | |
696 | ||
a68f4a27 DH |
697 | if (_service) |
698 | *_service = call->service_id; | |
540b1c48 | 699 | mutex_unlock(&call->user_mutex); |
eb9950eb | 700 | _leave(" = %d [%zu,%d]", ret, iov_iter_count(iter), *_abort); |
d001648e DH |
701 | return ret; |
702 | ||
703 | short_data: | |
fb46f6ee | 704 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("short_data")); |
d001648e DH |
705 | ret = -EBADMSG; |
706 | goto out; | |
707 | excess_data: | |
fb46f6ee | 708 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("excess_data")); |
d001648e DH |
709 | ret = -EMSGSIZE; |
710 | goto out; | |
711 | call_complete: | |
712 | *_abort = call->abort_code; | |
3a92789a | 713 | ret = call->error; |
d001648e DH |
714 | if (call->completion == RXRPC_CALL_SUCCEEDED) { |
715 | ret = 1; | |
eb9950eb | 716 | if (iov_iter_count(iter) > 0) |
d001648e DH |
717 | ret = -ECONNRESET; |
718 | } | |
719 | goto out; | |
720 | } | |
721 | EXPORT_SYMBOL(rxrpc_kernel_recv_data); | |
2070a3e4 DH |
722 | |
723 | /** | |
724 | * rxrpc_kernel_get_reply_time - Get timestamp on first reply packet | |
725 | * @sock: The socket that the call exists on | |
726 | * @call: The call to query | |
727 | * @_ts: Where to put the timestamp | |
728 | * | |
729 | * Retrieve the timestamp from the first DATA packet of the reply if it is | |
730 | * in the ring. Returns true if successful, false if not. | |
731 | */ | |
732 | bool rxrpc_kernel_get_reply_time(struct socket *sock, struct rxrpc_call *call, | |
733 | ktime_t *_ts) | |
734 | { | |
735 | struct sk_buff *skb; | |
736 | rxrpc_seq_t hard_ack, top, seq; | |
737 | bool success = false; | |
738 | ||
739 | mutex_lock(&call->user_mutex); | |
740 | ||
741 | if (READ_ONCE(call->state) != RXRPC_CALL_CLIENT_RECV_REPLY) | |
742 | goto out; | |
743 | ||
744 | hard_ack = call->rx_hard_ack; | |
745 | if (hard_ack != 0) | |
746 | goto out; | |
747 | ||
748 | seq = hard_ack + 1; | |
749 | top = smp_load_acquire(&call->rx_top); | |
750 | if (after(seq, top)) | |
751 | goto out; | |
752 | ||
753 | skb = call->rxtx_buffer[seq & RXRPC_RXTX_BUFF_MASK]; | |
754 | if (!skb) | |
755 | goto out; | |
756 | ||
757 | *_ts = skb_get_ktime(skb); | |
758 | success = true; | |
759 | ||
760 | out: | |
761 | mutex_unlock(&call->user_mutex); | |
762 | return success; | |
763 | } | |
764 | EXPORT_SYMBOL(rxrpc_kernel_get_reply_time); |