| /* RxRPC packet reception |
| * |
| * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| * Written by David Howells (dhowells@redhat.com) |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/module.h> |
| #include <linux/net.h> |
| #include <linux/skbuff.h> |
| #include <linux/errqueue.h> |
| #include <linux/udp.h> |
| #include <linux/in.h> |
| #include <linux/in6.h> |
| #include <linux/icmp.h> |
| #include <linux/gfp.h> |
| #include <net/sock.h> |
| #include <net/af_rxrpc.h> |
| #include <net/ip.h> |
| #include <net/udp.h> |
| #include <net/net_namespace.h> |
| #include "ar-internal.h" |
| |
| /* |
| * queue a packet for recvmsg to pass to userspace |
| * - the caller must hold a lock on call->lock |
| * - must not be called with interrupts disabled (sk_filter() disables BH's) |
| * - eats the packet whether successful or not |
| * - there must be just one reference to the packet, which the caller passes to |
| * this function |
| */ |
| int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb, |
| bool force, bool terminal) |
| { |
| struct rxrpc_skb_priv *sp; |
| struct rxrpc_sock *rx = call->socket; |
| struct sock *sk; |
| int ret; |
| |
| _enter(",,%d,%d", force, terminal); |
| |
| ASSERT(!irqs_disabled()); |
| |
| sp = rxrpc_skb(skb); |
| ASSERTCMP(sp->call, ==, call); |
| |
| /* if we've already posted the terminal message for a call, then we |
| * don't post any more */ |
| if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) { |
| _debug("already terminated"); |
| ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE); |
| rxrpc_free_skb(skb); |
| return 0; |
| } |
| |
| sk = &rx->sk; |
| |
| if (!force) { |
| /* cast skb->rcvbuf to unsigned... It's pointless, but |
| * reduces number of warnings when compiling with -W |
| * --ANK */ |
| // ret = -ENOBUFS; |
| // if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= |
| // (unsigned int) sk->sk_rcvbuf) |
| // goto out; |
| |
| ret = sk_filter(sk, skb); |
| if (ret < 0) |
| goto out; |
| } |
| |
| spin_lock_bh(&sk->sk_receive_queue.lock); |
| if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags) && |
| !test_bit(RXRPC_CALL_RELEASED, &call->flags) && |
| call->socket->sk.sk_state != RXRPC_CLOSE) { |
| skb->destructor = rxrpc_packet_destructor; |
| skb->dev = NULL; |
| skb->sk = sk; |
| atomic_add(skb->truesize, &sk->sk_rmem_alloc); |
| |
| if (terminal) { |
| _debug("<<<< TERMINAL MESSAGE >>>>"); |
| set_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags); |
| } |
| |
| /* allow interception by a kernel service */ |
| if (skb->mark == RXRPC_SKB_MARK_NEW_CALL && |
| rx->notify_new_call) { |
| spin_unlock_bh(&sk->sk_receive_queue.lock); |
| skb_queue_tail(&call->knlrecv_queue, skb); |
| rx->notify_new_call(&rx->sk); |
| } else if (call->notify_rx) { |
| spin_unlock_bh(&sk->sk_receive_queue.lock); |
| skb_queue_tail(&call->knlrecv_queue, skb); |
| call->notify_rx(&rx->sk, call, call->user_call_ID); |
| } else { |
| _net("post skb %p", skb); |
| __skb_queue_tail(&sk->sk_receive_queue, skb); |
| spin_unlock_bh(&sk->sk_receive_queue.lock); |
| |
| if (!sock_flag(sk, SOCK_DEAD)) |
| sk->sk_data_ready(sk); |
| } |
| skb = NULL; |
| } else { |
| spin_unlock_bh(&sk->sk_receive_queue.lock); |
| } |
| ret = 0; |
| |
| out: |
| rxrpc_free_skb(skb); |
| |
| _leave(" = %d", ret); |
| return ret; |
| } |
| |
| /* |
| * process a DATA packet, posting the packet to the appropriate queue |
| * - eats the packet if successful |
| */ |
| static int rxrpc_fast_process_data(struct rxrpc_call *call, |
| struct sk_buff *skb, u32 seq) |
| { |
| struct rxrpc_skb_priv *sp; |
| bool terminal; |
| int ret, ackbit, ack; |
| u32 serial; |
| u16 skew; |
| u8 flags; |
| |
| _enter("{%u,%u},,{%u}", call->rx_data_post, call->rx_first_oos, seq); |
| |
| sp = rxrpc_skb(skb); |
| ASSERTCMP(sp->call, ==, NULL); |
| flags = sp->hdr.flags; |
| serial = sp->hdr.serial; |
| skew = skb->priority; |
| |
| spin_lock(&call->lock); |
| |
| if (call->state > RXRPC_CALL_COMPLETE) |
| goto discard; |
| |
| ASSERTCMP(call->rx_data_expect, >=, call->rx_data_post); |
| ASSERTCMP(call->rx_data_post, >=, call->rx_data_recv); |
| ASSERTCMP(call->rx_data_recv, >=, call->rx_data_eaten); |
| |
| if (seq < call->rx_data_post) { |
| _debug("dup #%u [-%u]", seq, call->rx_data_post); |
| ack = RXRPC_ACK_DUPLICATE; |
| ret = -ENOBUFS; |
| goto discard_and_ack; |
| } |
| |
| /* we may already have the packet in the out of sequence queue */ |
| ackbit = seq - (call->rx_data_eaten + 1); |
| ASSERTCMP(ackbit, >=, 0); |
| if (__test_and_set_bit(ackbit, call->ackr_window)) { |
| _debug("dup oos #%u [%u,%u]", |
| seq, call->rx_data_eaten, call->rx_data_post); |
| ack = RXRPC_ACK_DUPLICATE; |
| goto discard_and_ack; |
| } |
| |
| if (seq >= call->ackr_win_top) { |
| _debug("exceed #%u [%u]", seq, call->ackr_win_top); |
| __clear_bit(ackbit, call->ackr_window); |
| ack = RXRPC_ACK_EXCEEDS_WINDOW; |
| goto discard_and_ack; |
| } |
| |
| if (seq == call->rx_data_expect) { |
| clear_bit(RXRPC_CALL_EXPECT_OOS, &call->flags); |
| call->rx_data_expect++; |
| } else if (seq > call->rx_data_expect) { |
| _debug("oos #%u [%u]", seq, call->rx_data_expect); |
| call->rx_data_expect = seq + 1; |
| if (test_and_set_bit(RXRPC_CALL_EXPECT_OOS, &call->flags)) { |
| ack = RXRPC_ACK_OUT_OF_SEQUENCE; |
| goto enqueue_and_ack; |
| } |
| goto enqueue_packet; |
| } |
| |
| if (seq != call->rx_data_post) { |
| _debug("ahead #%u [%u]", seq, call->rx_data_post); |
| goto enqueue_packet; |
| } |
| |
| if (test_bit(RXRPC_CALL_RCVD_LAST, &call->flags)) |
| goto protocol_error; |
| |
| /* if the packet need security things doing to it, then it goes down |
| * the slow path */ |
| if (call->conn->security_ix) |
| goto enqueue_packet; |
| |
| sp->call = call; |
| rxrpc_get_call_for_skb(call, skb); |
| terminal = ((flags & RXRPC_LAST_PACKET) && |
| !(flags & RXRPC_CLIENT_INITIATED)); |
| ret = rxrpc_queue_rcv_skb(call, skb, false, terminal); |
| if (ret < 0) { |
| if (ret == -ENOMEM || ret == -ENOBUFS) { |
| __clear_bit(ackbit, call->ackr_window); |
| ack = RXRPC_ACK_NOSPACE; |
| goto discard_and_ack; |
| } |
| goto out; |
| } |
| |
| skb = NULL; |
| sp = NULL; |
| |
| _debug("post #%u", seq); |
| ASSERTCMP(call->rx_data_post, ==, seq); |
| call->rx_data_post++; |
| |
| if (flags & RXRPC_LAST_PACKET) |
| set_bit(RXRPC_CALL_RCVD_LAST, &call->flags); |
| |
| /* if we've reached an out of sequence packet then we need to drain |
| * that queue into the socket Rx queue now */ |
| if (call->rx_data_post == call->rx_first_oos) { |
| _debug("drain rx oos now"); |
| read_lock(&call->state_lock); |
| if (call->state < RXRPC_CALL_COMPLETE && |
| !test_and_set_bit(RXRPC_CALL_EV_DRAIN_RX_OOS, &call->events)) |
| rxrpc_queue_call(call); |
| read_unlock(&call->state_lock); |
| } |
| |
| spin_unlock(&call->lock); |
| atomic_inc(&call->ackr_not_idle); |
| rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, skew, serial, false); |
| _leave(" = 0 [posted]"); |
| return 0; |
| |
| protocol_error: |
| ret = -EBADMSG; |
| out: |
| spin_unlock(&call->lock); |
| _leave(" = %d", ret); |
| return ret; |
| |
| discard_and_ack: |
| _debug("discard and ACK packet %p", skb); |
| __rxrpc_propose_ACK(call, ack, skew, serial, true); |
| discard: |
| spin_unlock(&call->lock); |
| rxrpc_free_skb(skb); |
| _leave(" = 0 [discarded]"); |
| return 0; |
| |
| enqueue_and_ack: |
| __rxrpc_propose_ACK(call, ack, skew, serial, true); |
| enqueue_packet: |
| _net("defer skb %p", skb); |
| spin_unlock(&call->lock); |
| skb_queue_tail(&call->rx_queue, skb); |
| atomic_inc(&call->ackr_not_idle); |
| read_lock(&call->state_lock); |
| if (call->state < RXRPC_CALL_DEAD) |
| rxrpc_queue_call(call); |
| read_unlock(&call->state_lock); |
| _leave(" = 0 [queued]"); |
| return 0; |
| } |
| |
| /* |
| * assume an implicit ACKALL of the transmission phase of a client socket upon |
| * reception of the first reply packet |
| */ |
| static void rxrpc_assume_implicit_ackall(struct rxrpc_call *call, u32 serial) |
| { |
| write_lock_bh(&call->state_lock); |
| |
| switch (call->state) { |
| case RXRPC_CALL_CLIENT_AWAIT_REPLY: |
| call->state = RXRPC_CALL_CLIENT_RECV_REPLY; |
| call->acks_latest = serial; |
| |
| _debug("implicit ACKALL %%%u", call->acks_latest); |
| set_bit(RXRPC_CALL_EV_RCVD_ACKALL, &call->events); |
| write_unlock_bh(&call->state_lock); |
| |
| if (try_to_del_timer_sync(&call->resend_timer) >= 0) { |
| clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events); |
| clear_bit(RXRPC_CALL_EV_RESEND, &call->events); |
| clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags); |
| } |
| break; |
| |
| default: |
| write_unlock_bh(&call->state_lock); |
| break; |
| } |
| } |
| |
| /* |
| * post an incoming packet to the nominated call to deal with |
| * - must get rid of the sk_buff, either by freeing it or by queuing it |
| */ |
| void rxrpc_fast_process_packet(struct rxrpc_call *call, struct sk_buff *skb) |
| { |
| struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
| __be32 wtmp; |
| u32 abort_code; |
| |
| _enter("%p,%p", call, skb); |
| |
| ASSERT(!irqs_disabled()); |
| |
| #if 0 // INJECT RX ERROR |
| if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA) { |
| static int skip = 0; |
| if (++skip == 3) { |
| printk("DROPPED 3RD PACKET!!!!!!!!!!!!!\n"); |
| skip = 0; |
| goto free_packet; |
| } |
| } |
| #endif |
| |
| /* request ACK generation for any ACK or DATA packet that requests |
| * it */ |
| if (sp->hdr.flags & RXRPC_REQUEST_ACK) { |
| _proto("ACK Requested on %%%u", sp->hdr.serial); |
| rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, |
| skb->priority, sp->hdr.serial, false); |
| } |
| |
| switch (sp->hdr.type) { |
| case RXRPC_PACKET_TYPE_ABORT: |
| _debug("abort"); |
| |
| if (skb_copy_bits(skb, 0, &wtmp, sizeof(wtmp)) < 0) |
| goto protocol_error; |
| |
| abort_code = ntohl(wtmp); |
| _proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code); |
| |
| if (__rxrpc_set_call_completion(call, |
| RXRPC_CALL_REMOTELY_ABORTED, |
| abort_code, ECONNABORTED)) { |
| set_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events); |
| rxrpc_queue_call(call); |
| } |
| goto free_packet; |
| |
| case RXRPC_PACKET_TYPE_BUSY: |
| _proto("Rx BUSY %%%u", sp->hdr.serial); |
| |
| if (rxrpc_conn_is_service(call->conn)) |
| goto protocol_error; |
| |
| write_lock_bh(&call->state_lock); |
| switch (call->state) { |
| case RXRPC_CALL_CLIENT_SEND_REQUEST: |
| __rxrpc_set_call_completion(call, |
| RXRPC_CALL_SERVER_BUSY, |
| 0, EBUSY); |
| set_bit(RXRPC_CALL_EV_RCVD_BUSY, &call->events); |
| rxrpc_queue_call(call); |
| case RXRPC_CALL_SERVER_BUSY: |
| goto free_packet_unlock; |
| default: |
| goto protocol_error_locked; |
| } |
| |
| default: |
| _proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], sp->hdr.serial); |
| goto protocol_error; |
| |
| case RXRPC_PACKET_TYPE_DATA: |
| _proto("Rx DATA %%%u { #%u }", sp->hdr.serial, sp->hdr.seq); |
| |
| if (sp->hdr.seq == 0) |
| goto protocol_error; |
| |
| call->ackr_prev_seq = sp->hdr.seq; |
| |
| /* received data implicitly ACKs all of the request packets we |
| * sent when we're acting as a client */ |
| if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) |
| rxrpc_assume_implicit_ackall(call, sp->hdr.serial); |
| |
| switch (rxrpc_fast_process_data(call, skb, sp->hdr.seq)) { |
| case 0: |
| skb = NULL; |
| goto done; |
| |
| default: |
| BUG(); |
| |
| /* data packet received beyond the last packet */ |
| case -EBADMSG: |
| goto protocol_error; |
| } |
| |
| case RXRPC_PACKET_TYPE_ACKALL: |
| case RXRPC_PACKET_TYPE_ACK: |
| /* ACK processing is done in process context */ |
| read_lock_bh(&call->state_lock); |
| if (call->state < RXRPC_CALL_DEAD) { |
| skb_queue_tail(&call->rx_queue, skb); |
| rxrpc_queue_call(call); |
| skb = NULL; |
| } |
| read_unlock_bh(&call->state_lock); |
| goto free_packet; |
| } |
| |
| protocol_error: |
| _debug("protocol error"); |
| write_lock_bh(&call->state_lock); |
| protocol_error_locked: |
| if (__rxrpc_abort_call(call, RX_PROTOCOL_ERROR, EPROTO)) |
| rxrpc_queue_call(call); |
| free_packet_unlock: |
| write_unlock_bh(&call->state_lock); |
| free_packet: |
| rxrpc_free_skb(skb); |
| done: |
| _leave(""); |
| } |
| |
| /* |
| * split up a jumbo data packet |
| */ |
| static void rxrpc_process_jumbo_packet(struct rxrpc_call *call, |
| struct sk_buff *jumbo) |
| { |
| struct rxrpc_jumbo_header jhdr; |
| struct rxrpc_skb_priv *sp; |
| struct sk_buff *part; |
| |
| _enter(",{%u,%u}", jumbo->data_len, jumbo->len); |
| |
| sp = rxrpc_skb(jumbo); |
| |
| do { |
| sp->hdr.flags &= ~RXRPC_JUMBO_PACKET; |
| |
| /* make a clone to represent the first subpacket in what's left |
| * of the jumbo packet */ |
| part = skb_clone(jumbo, GFP_ATOMIC); |
| if (!part) { |
| /* simply ditch the tail in the event of ENOMEM */ |
| pskb_trim(jumbo, RXRPC_JUMBO_DATALEN); |
| break; |
| } |
| rxrpc_new_skb(part); |
| |
| pskb_trim(part, RXRPC_JUMBO_DATALEN); |
| |
| if (!pskb_pull(jumbo, RXRPC_JUMBO_DATALEN)) |
| goto protocol_error; |
| |
| if (skb_copy_bits(jumbo, 0, &jhdr, sizeof(jhdr)) < 0) |
| goto protocol_error; |
| if (!pskb_pull(jumbo, sizeof(jhdr))) |
| BUG(); |
| |
| sp->hdr.seq += 1; |
| sp->hdr.serial += 1; |
| sp->hdr.flags = jhdr.flags; |
| sp->hdr._rsvd = ntohs(jhdr._rsvd); |
| |
| _proto("Rx DATA Jumbo %%%u", sp->hdr.serial - 1); |
| |
| rxrpc_fast_process_packet(call, part); |
| part = NULL; |
| |
| } while (sp->hdr.flags & RXRPC_JUMBO_PACKET); |
| |
| rxrpc_fast_process_packet(call, jumbo); |
| _leave(""); |
| return; |
| |
| protocol_error: |
| _debug("protocol error"); |
| rxrpc_free_skb(part); |
| rxrpc_free_skb(jumbo); |
| if (rxrpc_abort_call(call, RX_PROTOCOL_ERROR, EPROTO)) |
| rxrpc_queue_call(call); |
| _leave(""); |
| } |
| |
| /* |
| * post an incoming packet to the appropriate call/socket to deal with |
| * - must get rid of the sk_buff, either by freeing it or by queuing it |
| */ |
| static void rxrpc_post_packet_to_call(struct rxrpc_call *call, |
| struct sk_buff *skb) |
| { |
| struct rxrpc_skb_priv *sp; |
| |
| _enter("%p,%p", call, skb); |
| |
| sp = rxrpc_skb(skb); |
| |
| _debug("extant call [%d]", call->state); |
| |
| read_lock(&call->state_lock); |
| switch (call->state) { |
| case RXRPC_CALL_DEAD: |
| goto dead_call; |
| |
| case RXRPC_CALL_COMPLETE: |
| switch (call->completion) { |
| case RXRPC_CALL_LOCALLY_ABORTED: |
| if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, |
| &call->events)) { |
| rxrpc_queue_call(call); |
| goto free_unlock; |
| } |
| default: |
| goto dead_call; |
| case RXRPC_CALL_SUCCEEDED: |
| if (rxrpc_conn_is_service(call->conn)) |
| goto dead_call; |
| goto resend_final_ack; |
| } |
| |
| case RXRPC_CALL_CLIENT_FINAL_ACK: |
| goto resend_final_ack; |
| |
| default: |
| break; |
| } |
| |
| read_unlock(&call->state_lock); |
| rxrpc_get_call(call); |
| |
| if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA && |
| sp->hdr.flags & RXRPC_JUMBO_PACKET) |
| rxrpc_process_jumbo_packet(call, skb); |
| else |
| rxrpc_fast_process_packet(call, skb); |
| |
| rxrpc_put_call(call); |
| goto done; |
| |
| resend_final_ack: |
| _debug("final ack again"); |
| rxrpc_get_call(call); |
| set_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events); |
| rxrpc_queue_call(call); |
| goto free_unlock; |
| |
| dead_call: |
| if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) { |
| skb->priority = RX_CALL_DEAD; |
| rxrpc_reject_packet(call->conn->params.local, skb); |
| goto unlock; |
| } |
| free_unlock: |
| rxrpc_free_skb(skb); |
| unlock: |
| read_unlock(&call->state_lock); |
| done: |
| _leave(""); |
| } |
| |
| /* |
| * post connection-level events to the connection |
| * - this includes challenges, responses, some aborts and call terminal packet |
| * retransmission. |
| */ |
| static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn, |
| struct sk_buff *skb) |
| { |
| _enter("%p,%p", conn, skb); |
| |
| skb_queue_tail(&conn->rx_queue, skb); |
| rxrpc_queue_conn(conn); |
| } |
| |
| /* |
| * post endpoint-level events to the local endpoint |
| * - this includes debug and version messages |
| */ |
| static void rxrpc_post_packet_to_local(struct rxrpc_local *local, |
| struct sk_buff *skb) |
| { |
| _enter("%p,%p", local, skb); |
| |
| skb_queue_tail(&local->event_queue, skb); |
| rxrpc_queue_local(local); |
| } |
| |
| /* |
| * Extract the wire header from a packet and translate the byte order. |
| */ |
| static noinline |
| int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb) |
| { |
| struct rxrpc_wire_header whdr; |
| |
| /* dig out the RxRPC connection details */ |
| if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0) |
| return -EBADMSG; |
| if (!pskb_pull(skb, sizeof(whdr))) |
| BUG(); |
| |
| memset(sp, 0, sizeof(*sp)); |
| sp->hdr.epoch = ntohl(whdr.epoch); |
| sp->hdr.cid = ntohl(whdr.cid); |
| sp->hdr.callNumber = ntohl(whdr.callNumber); |
| sp->hdr.seq = ntohl(whdr.seq); |
| sp->hdr.serial = ntohl(whdr.serial); |
| sp->hdr.flags = whdr.flags; |
| sp->hdr.type = whdr.type; |
| sp->hdr.userStatus = whdr.userStatus; |
| sp->hdr.securityIndex = whdr.securityIndex; |
| sp->hdr._rsvd = ntohs(whdr._rsvd); |
| sp->hdr.serviceId = ntohs(whdr.serviceId); |
| return 0; |
| } |
| |
| /* |
| * handle data received on the local endpoint |
| * - may be called in interrupt context |
| * |
| * The socket is locked by the caller and this prevents the socket from being |
| * shut down and the local endpoint from going away, thus sk_user_data will not |
| * be cleared until this function returns. |
| */ |
| void rxrpc_data_ready(struct sock *sk) |
| { |
| struct rxrpc_connection *conn; |
| struct rxrpc_skb_priv *sp; |
| struct rxrpc_local *local = sk->sk_user_data; |
| struct sk_buff *skb; |
| int ret, skew; |
| |
| _enter("%p", sk); |
| |
| ASSERT(!irqs_disabled()); |
| |
| skb = skb_recv_datagram(sk, 0, 1, &ret); |
| if (!skb) { |
| if (ret == -EAGAIN) |
| return; |
| _debug("UDP socket error %d", ret); |
| return; |
| } |
| |
| rxrpc_new_skb(skb); |
| |
| _net("recv skb %p", skb); |
| |
| /* we'll probably need to checksum it (didn't call sock_recvmsg) */ |
| if (skb_checksum_complete(skb)) { |
| rxrpc_free_skb(skb); |
| __UDP_INC_STATS(&init_net, UDP_MIB_INERRORS, 0); |
| _leave(" [CSUM failed]"); |
| return; |
| } |
| |
| __UDP_INC_STATS(&init_net, UDP_MIB_INDATAGRAMS, 0); |
| |
| /* The socket buffer we have is owned by UDP, with UDP's data all over |
| * it, but we really want our own data there. |
| */ |
| skb_orphan(skb); |
| sp = rxrpc_skb(skb); |
| |
| _net("Rx UDP packet from %08x:%04hu", |
| ntohl(ip_hdr(skb)->saddr), ntohs(udp_hdr(skb)->source)); |
| |
| /* dig out the RxRPC connection details */ |
| if (rxrpc_extract_header(sp, skb) < 0) |
| goto bad_message; |
| |
| _net("Rx RxRPC %s ep=%x call=%x:%x", |
| sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient", |
| sp->hdr.epoch, sp->hdr.cid, sp->hdr.callNumber); |
| |
| if (sp->hdr.type >= RXRPC_N_PACKET_TYPES || |
| !((RXRPC_SUPPORTED_PACKET_TYPES >> sp->hdr.type) & 1)) { |
| _proto("Rx Bad Packet Type %u", sp->hdr.type); |
| goto bad_message; |
| } |
| |
| if (sp->hdr.type == RXRPC_PACKET_TYPE_VERSION) { |
| rxrpc_post_packet_to_local(local, skb); |
| goto out; |
| } |
| |
| if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA && |
| (sp->hdr.callNumber == 0 || sp->hdr.seq == 0)) |
| goto bad_message; |
| |
| rcu_read_lock(); |
| |
| conn = rxrpc_find_connection_rcu(local, skb); |
| if (!conn) { |
| skb->priority = 0; |
| goto cant_route_call; |
| } |
| |
| /* Note the serial number skew here */ |
| skew = (int)sp->hdr.serial - (int)conn->hi_serial; |
| if (skew >= 0) { |
| if (skew > 0) |
| conn->hi_serial = sp->hdr.serial; |
| skb->priority = 0; |
| } else { |
| skew = -skew; |
| skb->priority = min(skew, 65535); |
| } |
| |
| if (sp->hdr.callNumber == 0) { |
| /* Connection-level packet */ |
| _debug("CONN %p {%d}", conn, conn->debug_id); |
| rxrpc_post_packet_to_conn(conn, skb); |
| goto out_unlock; |
| } else { |
| /* Call-bound packets are routed by connection channel. */ |
| unsigned int channel = sp->hdr.cid & RXRPC_CHANNELMASK; |
| struct rxrpc_channel *chan = &conn->channels[channel]; |
| struct rxrpc_call *call; |
| |
| /* Ignore really old calls */ |
| if (sp->hdr.callNumber < chan->last_call) |
| goto discard_unlock; |
| |
| if (sp->hdr.callNumber == chan->last_call) { |
| /* For the previous service call, if completed |
| * successfully, we discard all further packets. |
| */ |
| if (rxrpc_conn_is_service(conn) && |
| (chan->last_type == RXRPC_PACKET_TYPE_ACK || |
| sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)) |
| goto discard_unlock; |
| |
| /* But otherwise we need to retransmit the final packet |
| * from data cached in the connection record. |
| */ |
| rxrpc_post_packet_to_conn(conn, skb); |
| goto out_unlock; |
| } |
| |
| call = rcu_dereference(chan->call); |
| if (!call || atomic_read(&call->usage) == 0) |
| goto cant_route_call; |
| |
| rxrpc_see_call(call); |
| rxrpc_post_packet_to_call(call, skb); |
| goto out_unlock; |
| } |
| |
| discard_unlock: |
| rxrpc_free_skb(skb); |
| out_unlock: |
| rcu_read_unlock(); |
| out: |
| return; |
| |
| cant_route_call: |
| rcu_read_unlock(); |
| |
| _debug("can't route call"); |
| if (sp->hdr.flags & RXRPC_CLIENT_INITIATED && |
| sp->hdr.type == RXRPC_PACKET_TYPE_DATA) { |
| if (sp->hdr.seq == 1) { |
| _debug("first packet"); |
| skb_queue_tail(&local->accept_queue, skb); |
| rxrpc_queue_work(&local->processor); |
| _leave(" [incoming]"); |
| return; |
| } |
| skb->priority = RX_INVALID_OPERATION; |
| } else { |
| skb->priority = RX_CALL_DEAD; |
| } |
| |
| if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) { |
| _debug("reject type %d",sp->hdr.type); |
| rxrpc_reject_packet(local, skb); |
| } else { |
| rxrpc_free_skb(skb); |
| } |
| _leave(" [no call]"); |
| return; |
| |
| bad_message: |
| skb->priority = RX_PROTOCOL_ERROR; |
| rxrpc_reject_packet(local, skb); |
| _leave(" [badmsg]"); |
| } |