net/rxrpc/local_event.c

   1 /* AF_RXRPC local endpoint management
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/net.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/slab.h>
  18 #include <net/sock.h>
  19 #include <net/af_rxrpc.h>
  20 #include <generated/utsrelease.h>
  21 #include "ar-internal.h"
  22
  23 static const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC";
  24
  25 /*
  26  * Reply to a version request
  27  */
  28 static void rxrpc_send_version_request(struct rxrpc_local *local,
  29                                        struct rxrpc_host_header *hdr,
  30                                        struct sk_buff *skb)
  31 {
  32         struct rxrpc_wire_header whdr;
  33         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
  34         struct sockaddr_rxrpc srx;
  35         struct msghdr msg;
  36         struct kvec iov[2];
  37         size_t len;
  38         int ret;
  39
  40         _enter("");
  41
  42         if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
  43                 return;
  44
  45         msg.msg_name    = &srx.transport;
  46         msg.msg_namelen = srx.transport_len;
  47         msg.msg_control = NULL;
  48         msg.msg_controllen = 0;
  49         msg.msg_flags   = 0;
  50
  51         whdr.epoch      = htonl(sp->hdr.epoch);
  52         whdr.cid        = htonl(sp->hdr.cid);
  53         whdr.callNumber = htonl(sp->hdr.callNumber);
  54         whdr.seq        = 0;
  55         whdr.serial     = 0;
  56         whdr.type       = RXRPC_PACKET_TYPE_VERSION;
  57         whdr.flags      = RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
  58         whdr.userStatus = 0;
  59         whdr.securityIndex = 0;
  60         whdr._rsvd      = 0;
  61         whdr.serviceId  = htons(sp->hdr.serviceId);
  62
  63         iov[0].iov_base = &whdr;
  64         iov[0].iov_len  = sizeof(whdr);
  65         iov[1].iov_base = (char *)rxrpc_version_string;
  66         iov[1].iov_len  = sizeof(rxrpc_version_string);
  67
  68         len = iov[0].iov_len + iov[1].iov_len;
  69
  70         _proto("Tx VERSION (reply)");
  71
  72         ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
  73         if (ret < 0)
  74                 trace_rxrpc_tx_fail(local->debug_id, 0, ret,
  75                                     rxrpc_tx_point_version_reply);
  76         else
  77                 trace_rxrpc_tx_packet(local->debug_id, &whdr,
  78                                       rxrpc_tx_point_version_reply);
  79
  80         _leave("");
  81 }
  82
  83 /*
  84  * Process event packets targetted at a local endpoint.
  85  */
  86 void rxrpc_process_local_events(struct rxrpc_local *local)
  87 {
  88         struct sk_buff *skb;
  89         char v;
  90
  91         _enter("");
  92
  93         skb = skb_dequeue(&local->event_queue);
  94         if (skb) {
  95                 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
  96
  97                 rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
  98                 _debug("{%d},{%u}", local->debug_id, sp->hdr.type);
  99
 100                 switch (sp->hdr.type) {
 101                 case RXRPC_PACKET_TYPE_VERSION:
 102                         if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
 103                                           &v, 1) < 0)
 104                                 return;
 105                         _proto("Rx VERSION { %02x }", v);
 106                         if (v == 0)
 107                                 rxrpc_send_version_request(local, &sp->hdr, skb);
 108                         break;
 109
 110                 default:
 111                         /* Just ignore anything we don't understand */
 112                         break;
 113                 }
 114
 115                 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
 116         }
 117
 118         _leave("");
 119 }