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 <linux/udp.h>
  19 #include <linux/ip.h>
  20 #include <net/sock.h>
  21 #include <net/af_rxrpc.h>
  22 #include <generated/utsrelease.h>
  23 #include "ar-internal.h"
  24
  25 static const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC";
  26
  27 /*
  28  * Reply to a version request
  29  */
  30 static void rxrpc_send_version_request(struct rxrpc_local *local,
  31                                        struct rxrpc_host_header *hdr,
  32                                        struct sk_buff *skb)
  33 {
  34         struct rxrpc_wire_header whdr;
  35         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
  36         struct sockaddr_in sin;
  37         struct msghdr msg;
  38         struct kvec iov[2];
  39         size_t len;
  40         int ret;
  41
  42         _enter("");
  43
  44         sin.sin_family = AF_INET;
  45         sin.sin_port = udp_hdr(skb)->source;
  46         sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
  47
  48         msg.msg_name    = &sin;
  49         msg.msg_namelen = sizeof(sin);
  50         msg.msg_control = NULL;
  51         msg.msg_controllen = 0;
  52         msg.msg_flags   = 0;
  53
  54         whdr.epoch      = htonl(sp->hdr.epoch);
  55         whdr.cid        = htonl(sp->hdr.cid);
  56         whdr.callNumber = htonl(sp->hdr.callNumber);
  57         whdr.seq        = 0;
  58         whdr.serial     = 0;
  59         whdr.type       = RXRPC_PACKET_TYPE_VERSION;
  60         whdr.flags      = RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
  61         whdr.userStatus = 0;
  62         whdr.securityIndex = 0;
  63         whdr._rsvd      = 0;
  64         whdr.serviceId  = htons(sp->hdr.serviceId);
  65
  66         iov[0].iov_base = &whdr;
  67         iov[0].iov_len  = sizeof(whdr);
  68         iov[1].iov_base = (char *)rxrpc_version_string;
  69         iov[1].iov_len  = sizeof(rxrpc_version_string);
  70
  71         len = iov[0].iov_len + iov[1].iov_len;
  72
  73         _proto("Tx VERSION (reply)");
  74
  75         ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
  76         if (ret < 0)
  77                 _debug("sendmsg failed: %d", ret);
  78
  79         _leave("");
  80 }
  81
  82 /*
  83  * Process event packets targetted at a local endpoint.
  84  */
  85 void rxrpc_process_local_events(struct rxrpc_local *local)
  86 {
  87         struct sk_buff *skb;
  88         char v;
  89
  90         _enter("");
  91
  92         skb = skb_dequeue(&local->event_queue);
  93         if (skb) {
  94                 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
  95
  96                 rxrpc_see_skb(skb);
  97                 _debug("{%d},{%u}", local->debug_id, sp->hdr.type);
  98
  99                 switch (sp->hdr.type) {
 100                 case RXRPC_PACKET_TYPE_VERSION:
 101                         if (skb_copy_bits(skb, sp->offset, &v, 1) < 0)
 102                                 return;
 103                         _proto("Rx VERSION { %02x }", v);
 104                         if (v == 0)
 105                                 rxrpc_send_version_request(local, &sp->hdr, skb);
 106                         break;
 107
 108                 default:
 109                         /* Just ignore anything we don't understand */
 110                         break;
 111                 }
 112
 113                 rxrpc_free_skb(skb);
 114         }
 115
 116         _leave("");
 117 }