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Commit | Line | Data |
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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) { |
a71a2651 | 144 | rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, 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 DH |
161 | write_unlock_bh(&call->state_lock); |
162 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true, | |
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; |
816c9fce | 180 | u8 flags; |
248f219c DH |
181 | int ix; |
182 | ||
183 | _enter("%d", call->debug_id); | |
184 | ||
185 | hard_ack = call->rx_hard_ack; | |
186 | top = smp_load_acquire(&call->rx_top); | |
187 | ASSERT(before(hard_ack, top)); | |
188 | ||
189 | hard_ack++; | |
190 | ix = hard_ack & RXRPC_RXTX_BUFF_MASK; | |
191 | skb = call->rxtx_buffer[ix]; | |
71f3ca40 | 192 | rxrpc_see_skb(skb, rxrpc_skb_rx_rotated); |
816c9fce DH |
193 | sp = rxrpc_skb(skb); |
194 | flags = sp->hdr.flags; | |
58dc63c9 DH |
195 | serial = sp->hdr.serial; |
196 | if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) | |
197 | serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1; | |
198 | ||
248f219c DH |
199 | call->rxtx_buffer[ix] = NULL; |
200 | call->rxtx_annotations[ix] = 0; | |
201 | /* Barrier against rxrpc_input_data(). */ | |
202 | smp_store_release(&call->rx_hard_ack, hard_ack); | |
17926a79 | 203 | |
71f3ca40 | 204 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
17926a79 | 205 | |
816c9fce | 206 | _debug("%u,%u,%02x", hard_ack, top, flags); |
58dc63c9 | 207 | trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); |
805b21b9 | 208 | if (flags & RXRPC_LAST_PACKET) { |
b69d94d7 | 209 | rxrpc_end_rx_phase(call, serial); |
805b21b9 DH |
210 | } else { |
211 | /* Check to see if there's an ACK that needs sending. */ | |
212 | if (after_eq(hard_ack, call->ackr_consumed + 2) || | |
213 | after_eq(top, call->ackr_seen + 2) || | |
214 | (hard_ack == top && after(hard_ack, call->ackr_consumed))) | |
215 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, | |
8637abaa | 216 | true, true, |
805b21b9 | 217 | rxrpc_propose_ack_rotate_rx); |
8637abaa | 218 | if (call->ackr_reason && call->ackr_reason != RXRPC_ACK_DELAY) |
bd1fdf8c | 219 | rxrpc_send_ack_packet(call, false, NULL); |
805b21b9 | 220 | } |
248f219c DH |
221 | } |
222 | ||
223 | /* | |
224 | * Decrypt and verify a (sub)packet. The packet's length may be changed due to | |
225 | * padding, but if this is the case, the packet length will be resident in the | |
226 | * socket buffer. Note that we can't modify the master skb info as the skb may | |
227 | * be the home to multiple subpackets. | |
228 | */ | |
229 | static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb, | |
230 | u8 annotation, | |
231 | unsigned int offset, unsigned int len) | |
232 | { | |
233 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
234 | rxrpc_seq_t seq = sp->hdr.seq; | |
235 | u16 cksum = sp->hdr.cksum; | |
236 | ||
237 | _enter(""); | |
238 | ||
239 | /* For all but the head jumbo subpacket, the security checksum is in a | |
240 | * jumbo header immediately prior to the data. | |
241 | */ | |
242 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) { | |
243 | __be16 tmp; | |
244 | if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0) | |
245 | BUG(); | |
246 | cksum = ntohs(tmp); | |
247 | seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1; | |
248 | } | |
249 | ||
250 | return call->conn->security->verify_packet(call, skb, offset, len, | |
251 | seq, cksum); | |
252 | } | |
253 | ||
254 | /* | |
255 | * Locate the data within a packet. This is complicated by: | |
256 | * | |
257 | * (1) An skb may contain a jumbo packet - so we have to find the appropriate | |
258 | * subpacket. | |
259 | * | |
260 | * (2) The (sub)packets may be encrypted and, if so, the encrypted portion | |
261 | * contains an extra header which includes the true length of the data, | |
262 | * excluding any encrypted padding. | |
263 | */ | |
264 | static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb, | |
265 | u8 *_annotation, | |
266 | unsigned int *_offset, unsigned int *_len) | |
267 | { | |
775e5b71 | 268 | unsigned int offset = sizeof(struct rxrpc_wire_header); |
650b4eca | 269 | unsigned int len; |
248f219c DH |
270 | int ret; |
271 | u8 annotation = *_annotation; | |
272 | ||
248f219c | 273 | /* Locate the subpacket */ |
775e5b71 | 274 | len = skb->len - offset; |
248f219c DH |
275 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) { |
276 | offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) * | |
277 | RXRPC_JUMBO_SUBPKTLEN); | |
278 | len = (annotation & RXRPC_RX_ANNO_JLAST) ? | |
279 | skb->len - offset : RXRPC_JUMBO_SUBPKTLEN; | |
280 | } | |
281 | ||
282 | if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) { | |
283 | ret = rxrpc_verify_packet(call, skb, annotation, offset, len); | |
17926a79 | 284 | if (ret < 0) |
248f219c DH |
285 | return ret; |
286 | *_annotation |= RXRPC_RX_ANNO_VERIFIED; | |
287 | } | |
17926a79 | 288 | |
248f219c DH |
289 | *_offset = offset; |
290 | *_len = len; | |
291 | call->conn->security->locate_data(call, skb, _offset, _len); | |
292 | return 0; | |
293 | } | |
17926a79 | 294 | |
248f219c DH |
295 | /* |
296 | * Deliver messages to a call. This keeps processing packets until the buffer | |
297 | * is filled and we find either more DATA (returns 0) or the end of the DATA | |
298 | * (returns 1). If more packets are required, it returns -EAGAIN. | |
299 | */ | |
300 | static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call, | |
301 | struct msghdr *msg, struct iov_iter *iter, | |
302 | size_t len, int flags, size_t *_offset) | |
303 | { | |
304 | struct rxrpc_skb_priv *sp; | |
305 | struct sk_buff *skb; | |
306 | rxrpc_seq_t hard_ack, top, seq; | |
307 | size_t remain; | |
308 | bool last; | |
309 | unsigned int rx_pkt_offset, rx_pkt_len; | |
816c9fce | 310 | int ix, copy, ret = -EAGAIN, ret2; |
248f219c | 311 | |
d0b35a42 DH |
312 | if (test_and_clear_bit(RXRPC_CALL_RX_UNDERRUN, &call->flags) && |
313 | call->ackr_reason) | |
314 | rxrpc_send_ack_packet(call, false, NULL); | |
315 | ||
248f219c DH |
316 | rx_pkt_offset = call->rx_pkt_offset; |
317 | rx_pkt_len = call->rx_pkt_len; | |
318 | ||
816c9fce DH |
319 | if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) { |
320 | seq = call->rx_hard_ack; | |
321 | ret = 1; | |
322 | goto done; | |
323 | } | |
324 | ||
248f219c DH |
325 | /* Barriers against rxrpc_input_data(). */ |
326 | hard_ack = call->rx_hard_ack; | |
d7e15835 DH |
327 | seq = hard_ack + 1; |
328 | while (top = smp_load_acquire(&call->rx_top), | |
329 | before_eq(seq, top) | |
330 | ) { | |
248f219c DH |
331 | ix = seq & RXRPC_RXTX_BUFF_MASK; |
332 | skb = call->rxtx_buffer[ix]; | |
84997905 DH |
333 | if (!skb) { |
334 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq, | |
335 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 336 | break; |
84997905 | 337 | } |
248f219c | 338 | smp_rmb(); |
71f3ca40 | 339 | rxrpc_see_skb(skb, rxrpc_skb_rx_seen); |
248f219c | 340 | sp = rxrpc_skb(skb); |
17926a79 | 341 | |
58dc63c9 DH |
342 | if (!(flags & MSG_PEEK)) |
343 | trace_rxrpc_receive(call, rxrpc_receive_front, | |
344 | sp->hdr.serial, seq); | |
345 | ||
248f219c DH |
346 | if (msg) |
347 | sock_recv_timestamp(msg, sock->sk, skb); | |
348 | ||
2e2ea51d | 349 | if (rx_pkt_offset == 0) { |
816c9fce DH |
350 | ret2 = rxrpc_locate_data(call, skb, |
351 | &call->rxtx_annotations[ix], | |
352 | &rx_pkt_offset, &rx_pkt_len); | |
84997905 DH |
353 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq, |
354 | rx_pkt_offset, rx_pkt_len, ret2); | |
816c9fce DH |
355 | if (ret2 < 0) { |
356 | ret = ret2; | |
2e2ea51d | 357 | goto out; |
816c9fce | 358 | } |
84997905 DH |
359 | } else { |
360 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq, | |
361 | rx_pkt_offset, rx_pkt_len, 0); | |
2e2ea51d | 362 | } |
248f219c DH |
363 | |
364 | /* We have to handle short, empty and used-up DATA packets. */ | |
365 | remain = len - *_offset; | |
366 | copy = rx_pkt_len; | |
367 | if (copy > remain) | |
368 | copy = remain; | |
369 | if (copy > 0) { | |
816c9fce DH |
370 | ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter, |
371 | copy); | |
372 | if (ret2 < 0) { | |
373 | ret = ret2; | |
248f219c | 374 | goto out; |
816c9fce | 375 | } |
248f219c DH |
376 | |
377 | /* handle piecemeal consumption of data packets */ | |
248f219c DH |
378 | rx_pkt_offset += copy; |
379 | rx_pkt_len -= copy; | |
380 | *_offset += copy; | |
381 | } | |
17926a79 | 382 | |
248f219c | 383 | if (rx_pkt_len > 0) { |
84997905 DH |
384 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq, |
385 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 386 | ASSERTCMP(*_offset, ==, len); |
816c9fce | 387 | ret = 0; |
17926a79 DH |
388 | break; |
389 | } | |
390 | ||
248f219c DH |
391 | /* The whole packet has been transferred. */ |
392 | last = sp->hdr.flags & RXRPC_LAST_PACKET; | |
372ee163 | 393 | if (!(flags & MSG_PEEK)) |
248f219c DH |
394 | rxrpc_rotate_rx_window(call); |
395 | rx_pkt_offset = 0; | |
396 | rx_pkt_len = 0; | |
17926a79 | 397 | |
816c9fce DH |
398 | if (last) { |
399 | ASSERTCMP(seq, ==, READ_ONCE(call->rx_top)); | |
248f219c | 400 | ret = 1; |
816c9fce DH |
401 | goto out; |
402 | } | |
d7e15835 DH |
403 | |
404 | seq++; | |
248f219c | 405 | } |
816c9fce | 406 | |
248f219c DH |
407 | out: |
408 | if (!(flags & MSG_PEEK)) { | |
409 | call->rx_pkt_offset = rx_pkt_offset; | |
410 | call->rx_pkt_len = rx_pkt_len; | |
411 | } | |
816c9fce | 412 | done: |
84997905 DH |
413 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq, |
414 | rx_pkt_offset, rx_pkt_len, ret); | |
d0b35a42 DH |
415 | if (ret == -EAGAIN) |
416 | set_bit(RXRPC_CALL_RX_UNDERRUN, &call->flags); | |
248f219c DH |
417 | return ret; |
418 | } | |
17926a79 | 419 | |
248f219c DH |
420 | /* |
421 | * Receive a message from an RxRPC socket | |
422 | * - we need to be careful about two or more threads calling recvmsg | |
423 | * simultaneously | |
424 | */ | |
425 | int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, | |
426 | int flags) | |
427 | { | |
428 | struct rxrpc_call *call; | |
429 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); | |
430 | struct list_head *l; | |
431 | size_t copied = 0; | |
432 | long timeo; | |
433 | int ret; | |
434 | ||
435 | DEFINE_WAIT(wait); | |
436 | ||
84997905 | 437 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0); |
248f219c DH |
438 | |
439 | if (flags & (MSG_OOB | MSG_TRUNC)) | |
440 | return -EOPNOTSUPP; | |
441 | ||
442 | timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); | |
443 | ||
444 | try_again: | |
445 | lock_sock(&rx->sk); | |
446 | ||
447 | /* Return immediately if a client socket has no outstanding calls */ | |
448 | if (RB_EMPTY_ROOT(&rx->calls) && | |
449 | list_empty(&rx->recvmsg_q) && | |
450 | rx->sk.sk_state != RXRPC_SERVER_LISTENING) { | |
451 | release_sock(&rx->sk); | |
452 | return -ENODATA; | |
17926a79 DH |
453 | } |
454 | ||
248f219c DH |
455 | if (list_empty(&rx->recvmsg_q)) { |
456 | ret = -EWOULDBLOCK; | |
84997905 DH |
457 | if (timeo == 0) { |
458 | call = NULL; | |
248f219c | 459 | goto error_no_call; |
84997905 | 460 | } |
248f219c DH |
461 | |
462 | release_sock(&rx->sk); | |
463 | ||
464 | /* Wait for something to happen */ | |
465 | prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, | |
466 | TASK_INTERRUPTIBLE); | |
467 | ret = sock_error(&rx->sk); | |
468 | if (ret) | |
469 | goto wait_error; | |
470 | ||
471 | if (list_empty(&rx->recvmsg_q)) { | |
472 | if (signal_pending(current)) | |
473 | goto wait_interrupted; | |
84997905 DH |
474 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, |
475 | 0, 0, 0, 0); | |
248f219c | 476 | timeo = schedule_timeout(timeo); |
17926a79 | 477 | } |
248f219c DH |
478 | finish_wait(sk_sleep(&rx->sk), &wait); |
479 | goto try_again; | |
17926a79 DH |
480 | } |
481 | ||
248f219c DH |
482 | /* Find the next call and dequeue it if we're not just peeking. If we |
483 | * do dequeue it, that comes with a ref that we will need to release. | |
484 | */ | |
485 | write_lock_bh(&rx->recvmsg_lock); | |
486 | l = rx->recvmsg_q.next; | |
487 | call = list_entry(l, struct rxrpc_call, recvmsg_link); | |
488 | if (!(flags & MSG_PEEK)) | |
489 | list_del_init(&call->recvmsg_link); | |
490 | else | |
491 | rxrpc_get_call(call, rxrpc_call_got); | |
492 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 493 | |
84997905 | 494 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0); |
248f219c | 495 | |
540b1c48 DH |
496 | /* We're going to drop the socket lock, so we need to lock the call |
497 | * against interference by sendmsg. | |
498 | */ | |
499 | if (!mutex_trylock(&call->user_mutex)) { | |
500 | ret = -EWOULDBLOCK; | |
501 | if (flags & MSG_DONTWAIT) | |
502 | goto error_requeue_call; | |
503 | ret = -ERESTARTSYS; | |
504 | if (mutex_lock_interruptible(&call->user_mutex) < 0) | |
505 | goto error_requeue_call; | |
506 | } | |
507 | ||
508 | release_sock(&rx->sk); | |
509 | ||
248f219c | 510 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) |
17926a79 | 511 | BUG(); |
248f219c DH |
512 | |
513 | if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { | |
514 | if (flags & MSG_CMSG_COMPAT) { | |
515 | unsigned int id32 = call->user_call_ID; | |
516 | ||
517 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
518 | sizeof(unsigned int), &id32); | |
519 | } else { | |
a16b8d0c DH |
520 | unsigned long idl = call->user_call_ID; |
521 | ||
248f219c | 522 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, |
a16b8d0c | 523 | sizeof(unsigned long), &idl); |
f5c17aae | 524 | } |
248f219c | 525 | if (ret < 0) |
540b1c48 | 526 | goto error_unlock_call; |
248f219c DH |
527 | } |
528 | ||
529 | if (msg->msg_name) { | |
68d6d1ae DH |
530 | struct sockaddr_rxrpc *srx = msg->msg_name; |
531 | size_t len = sizeof(call->peer->srx); | |
532 | ||
533 | memcpy(msg->msg_name, &call->peer->srx, len); | |
534 | srx->srx_service = call->service_id; | |
248f219c DH |
535 | msg->msg_namelen = len; |
536 | } | |
537 | ||
146d8fef | 538 | switch (READ_ONCE(call->state)) { |
248f219c DH |
539 | case RXRPC_CALL_SERVER_ACCEPTING: |
540 | ret = rxrpc_recvmsg_new_call(rx, call, msg, flags); | |
17926a79 | 541 | break; |
248f219c DH |
542 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
543 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
544 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
545 | ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len, | |
546 | flags, &copied); | |
547 | if (ret == -EAGAIN) | |
548 | ret = 0; | |
33b603fd DH |
549 | |
550 | if (after(call->rx_top, call->rx_hard_ack) && | |
551 | call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK]) | |
552 | rxrpc_notify_socket(call); | |
17926a79 DH |
553 | break; |
554 | default: | |
248f219c | 555 | ret = 0; |
17926a79 DH |
556 | break; |
557 | } | |
558 | ||
559 | if (ret < 0) | |
540b1c48 | 560 | goto error_unlock_call; |
17926a79 | 561 | |
248f219c DH |
562 | if (call->state == RXRPC_CALL_COMPLETE) { |
563 | ret = rxrpc_recvmsg_term(call, msg); | |
564 | if (ret < 0) | |
540b1c48 | 565 | goto error_unlock_call; |
248f219c DH |
566 | if (!(flags & MSG_PEEK)) |
567 | rxrpc_release_call(rx, call); | |
568 | msg->msg_flags |= MSG_EOR; | |
569 | ret = 1; | |
17926a79 DH |
570 | } |
571 | ||
248f219c DH |
572 | if (ret == 0) |
573 | msg->msg_flags |= MSG_MORE; | |
574 | else | |
575 | msg->msg_flags &= ~MSG_MORE; | |
576 | ret = copied; | |
17926a79 | 577 | |
540b1c48 DH |
578 | error_unlock_call: |
579 | mutex_unlock(&call->user_mutex); | |
fff72429 | 580 | rxrpc_put_call(call, rxrpc_call_put); |
540b1c48 DH |
581 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
582 | return ret; | |
583 | ||
584 | error_requeue_call: | |
585 | if (!(flags & MSG_PEEK)) { | |
586 | write_lock_bh(&rx->recvmsg_lock); | |
587 | list_add(&call->recvmsg_link, &rx->recvmsg_q); | |
588 | write_unlock_bh(&rx->recvmsg_lock); | |
589 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_requeue, 0, 0, 0, 0); | |
590 | } else { | |
591 | rxrpc_put_call(call, rxrpc_call_put); | |
592 | } | |
248f219c DH |
593 | error_no_call: |
594 | release_sock(&rx->sk); | |
6dce3c20 | 595 | error_trace: |
84997905 | 596 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
17926a79 DH |
597 | return ret; |
598 | ||
17926a79 DH |
599 | wait_interrupted: |
600 | ret = sock_intr_errno(timeo); | |
601 | wait_error: | |
4a4771a5 | 602 | finish_wait(sk_sleep(&rx->sk), &wait); |
84997905 | 603 | call = NULL; |
6dce3c20 | 604 | goto error_trace; |
d001648e | 605 | } |
651350d1 DH |
606 | |
607 | /** | |
d001648e DH |
608 | * rxrpc_kernel_recv_data - Allow a kernel service to receive data/info |
609 | * @sock: The socket that the call exists on | |
610 | * @call: The call to send data through | |
eb9950eb | 611 | * @iter: The buffer to receive into |
d001648e DH |
612 | * @want_more: True if more data is expected to be read |
613 | * @_abort: Where the abort code is stored if -ECONNABORTED is returned | |
a68f4a27 | 614 | * @_service: Where to store the actual service ID (may be upgraded) |
d001648e DH |
615 | * |
616 | * Allow a kernel service to receive data and pick up information about the | |
617 | * state of a call. Returns 0 if got what was asked for and there's more | |
618 | * available, 1 if we got what was asked for and we're at the end of the data | |
619 | * and -EAGAIN if we need more data. | |
620 | * | |
621 | * Note that we may return -EAGAIN to drain empty packets at the end of the | |
622 | * data, even if we've already copied over the requested data. | |
651350d1 | 623 | * |
d001648e | 624 | * *_abort should also be initialised to 0. |
651350d1 | 625 | */ |
d001648e | 626 | int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call, |
eb9950eb | 627 | struct iov_iter *iter, |
a68f4a27 | 628 | bool want_more, u32 *_abort, u16 *_service) |
651350d1 | 629 | { |
eb9950eb | 630 | size_t offset = 0; |
d001648e | 631 | int ret; |
651350d1 | 632 | |
eb9950eb | 633 | _enter("{%d,%s},%zu,%d", |
248f219c | 634 | call->debug_id, rxrpc_call_states[call->state], |
eb9950eb | 635 | iov_iter_count(iter), want_more); |
d001648e | 636 | |
d001648e | 637 | ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING); |
651350d1 | 638 | |
540b1c48 | 639 | mutex_lock(&call->user_mutex); |
d001648e | 640 | |
146d8fef | 641 | switch (READ_ONCE(call->state)) { |
d001648e DH |
642 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
643 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
644 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
eb9950eb DH |
645 | ret = rxrpc_recvmsg_data(sock, call, NULL, iter, |
646 | iov_iter_count(iter), 0, | |
647 | &offset); | |
d001648e DH |
648 | if (ret < 0) |
649 | goto out; | |
650 | ||
651 | /* We can only reach here with a partially full buffer if we | |
652 | * have reached the end of the data. We must otherwise have a | |
653 | * full buffer or have been given -EAGAIN. | |
654 | */ | |
655 | if (ret == 1) { | |
eb9950eb | 656 | if (iov_iter_count(iter) > 0) |
d001648e DH |
657 | goto short_data; |
658 | if (!want_more) | |
659 | goto read_phase_complete; | |
660 | ret = 0; | |
661 | goto out; | |
662 | } | |
663 | ||
664 | if (!want_more) | |
665 | goto excess_data; | |
666 | goto out; | |
667 | ||
668 | case RXRPC_CALL_COMPLETE: | |
669 | goto call_complete; | |
670 | ||
671 | default: | |
d001648e DH |
672 | ret = -EINPROGRESS; |
673 | goto out; | |
674 | } | |
675 | ||
676 | read_phase_complete: | |
677 | ret = 1; | |
678 | out: | |
d0b35a42 DH |
679 | switch (call->ackr_reason) { |
680 | case RXRPC_ACK_IDLE: | |
681 | break; | |
682 | case RXRPC_ACK_DELAY: | |
683 | if (ret != -EAGAIN) | |
684 | break; | |
685 | /* Fall through */ | |
686 | default: | |
687 | rxrpc_send_ack_packet(call, false, NULL); | |
688 | } | |
689 | ||
a68f4a27 DH |
690 | if (_service) |
691 | *_service = call->service_id; | |
540b1c48 | 692 | mutex_unlock(&call->user_mutex); |
eb9950eb | 693 | _leave(" = %d [%zu,%d]", ret, iov_iter_count(iter), *_abort); |
d001648e DH |
694 | return ret; |
695 | ||
696 | short_data: | |
fb46f6ee | 697 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("short_data")); |
d001648e DH |
698 | ret = -EBADMSG; |
699 | goto out; | |
700 | excess_data: | |
fb46f6ee | 701 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("excess_data")); |
d001648e DH |
702 | ret = -EMSGSIZE; |
703 | goto out; | |
704 | call_complete: | |
705 | *_abort = call->abort_code; | |
3a92789a | 706 | ret = call->error; |
d001648e DH |
707 | if (call->completion == RXRPC_CALL_SUCCEEDED) { |
708 | ret = 1; | |
eb9950eb | 709 | if (iov_iter_count(iter) > 0) |
d001648e DH |
710 | ret = -ECONNRESET; |
711 | } | |
712 | goto out; | |
713 | } | |
714 | EXPORT_SYMBOL(rxrpc_kernel_recv_data); | |
2070a3e4 DH |
715 | |
716 | /** | |
717 | * rxrpc_kernel_get_reply_time - Get timestamp on first reply packet | |
718 | * @sock: The socket that the call exists on | |
719 | * @call: The call to query | |
720 | * @_ts: Where to put the timestamp | |
721 | * | |
722 | * Retrieve the timestamp from the first DATA packet of the reply if it is | |
723 | * in the ring. Returns true if successful, false if not. | |
724 | */ | |
725 | bool rxrpc_kernel_get_reply_time(struct socket *sock, struct rxrpc_call *call, | |
726 | ktime_t *_ts) | |
727 | { | |
728 | struct sk_buff *skb; | |
729 | rxrpc_seq_t hard_ack, top, seq; | |
730 | bool success = false; | |
731 | ||
732 | mutex_lock(&call->user_mutex); | |
733 | ||
734 | if (READ_ONCE(call->state) != RXRPC_CALL_CLIENT_RECV_REPLY) | |
735 | goto out; | |
736 | ||
737 | hard_ack = call->rx_hard_ack; | |
738 | if (hard_ack != 0) | |
739 | goto out; | |
740 | ||
741 | seq = hard_ack + 1; | |
742 | top = smp_load_acquire(&call->rx_top); | |
743 | if (after(seq, top)) | |
744 | goto out; | |
745 | ||
746 | skb = call->rxtx_buffer[seq & RXRPC_RXTX_BUFF_MASK]; | |
747 | if (!skb) | |
748 | goto out; | |
749 | ||
750 | *_ts = skb_get_ktime(skb); | |
751 | success = true; | |
752 | ||
753 | out: | |
754 | mutex_unlock(&call->user_mutex); | |
755 | return success; | |
756 | } | |
757 | EXPORT_SYMBOL(rxrpc_kernel_get_reply_time); |