root/net/802/p8022tr.c

/* */

DEFINITIONS

1. find_8022tr_client
2. p8022tr_rcv
3. p8022tr_datalink_header
4. p8022tr_proto_init
5. register_8022tr_client
6. unregister_8022tr_client

   1 #include <linux/module.h>
   2 #include <linux/netdevice.h>
   3 #include <linux/skbuff.h>
   4 #include <net/datalink.h>
   5 #include <linux/mm.h>
   6 #include <linux/in.h>
   7 #include <net/p8022tr.h>
   8 
   9 #define SNAP_HEADER_LEN 8
  10 
  11 static struct datalink_proto *p8022tr_list = NULL;
  12 
  13 /*
  14  *      We don't handle the loopback SAP stuff, the extended
  15  *      802.2 command set, multicast SAP identifiers and non UI
  16  *      frames. We have the absolute minimum needed for IPX,
  17  *      IP and Appletalk phase 2.
  18  */
  19  
  20 static struct datalink_proto *
  21 find_8022tr_client(unsigned char type)
     /*  */
  22 {
  23         struct datalink_proto   *proto;
  24 
  25         for (proto = p8022tr_list;
  26                 ((proto != NULL) && (*(proto->type) != type));
  27                 proto = proto->next)
  28                 ;
  29 
  30         return proto;
  31 }
  32 
  33 int
  34 p8022tr_rcv(struct sk_buff *skb, struct device *dev, struct packet_type *pt)
     /*  */
  35 {
  36         struct datalink_proto   *proto;
  37 
  38         proto = find_8022tr_client(*(skb->h.raw));
  39         if (proto != NULL) {
  40                 skb->h.raw += 3;
  41                 skb_pull(skb,3);
  42                 return proto->rcvfunc(skb, dev, pt);
  43         }
  44 
  45         skb->sk = NULL;
  46         kfree_skb(skb, FREE_READ);
  47         return 0;
  48 }
  49 
  50 static void
  51 p8022tr_datalink_header(struct datalink_proto *dl, 
     /*  */
  52                 struct sk_buff *skb, unsigned char *dest_node)
  53 {
  54         struct device   *dev = skb->dev;
  55         unsigned char   *rawp;
  56         unsigned char   *olddata;
  57         unsigned char   *newdata;
  58 
  59         rawp = skb_push(skb,3);
  60         *rawp++ = dl->type[0];
  61         *rawp++ = dl->type[0];
  62         *rawp = 0x03;   /* UI */
  63         dev->hard_header(skb, dev, ETH_P_802_3, dest_node, NULL, skb->len);
  64         olddata = skb->data;
  65         newdata = skb_pull(skb, SNAP_HEADER_LEN);
  66         memmove(newdata, olddata, dev->hard_header_len - SNAP_HEADER_LEN);
  67 }
  68 
  69 static struct packet_type p8022tr_packet_type = 
  70 {
  71         0,      
  72         NULL,           /* All devices */
  73         p8022tr_rcv,
  74         NULL,
  75         NULL,
  76 };
  77  
  78 
  79 static struct symbol_table p8022tr_proto_syms = {
  80 #include <linux/symtab_begin.h>
  81         X(register_8022tr_client),
  82         X(unregister_8022tr_client),
  83 #include <linux/symtab_end.h>
  84 };
  85 
  86 void p8022tr_proto_init(struct net_proto *pro)
     /*  */
  87 {
  88         p8022tr_packet_type.type=htons(ETH_P_TR_802_2);
  89         dev_add_pack(&p8022tr_packet_type);
  90         register_symtab(&p8022tr_proto_syms);
  91 }
  92         
  93 struct datalink_proto *
  94 register_8022tr_client(unsigned char type, int (*rcvfunc)(struct sk_buff *, struct device *, struct packet_type *))
     /*  */
  95 {
  96         struct datalink_proto   *proto;
  97 
  98         if (find_8022tr_client(type) != NULL)
  99                 return NULL;
 100 
 101         proto = (struct datalink_proto *) kmalloc(sizeof(*proto), GFP_ATOMIC);
 102         if (proto != NULL) {
 103                 proto->type[0] = type;
 104                 proto->type_len = 1;
 105                 proto->rcvfunc = rcvfunc;
 106                 proto->header_length = 3;
 107                 proto->datalink_header = p8022tr_datalink_header;
 108                 proto->string_name = "802.2TR";
 109                 proto->next = p8022tr_list;
 110                 p8022tr_list = proto;
 111         }
 112 
 113         return proto;
 114 }
 115 
 116 void unregister_8022tr_client(unsigned char type)
     /*  */
 117 {
 118         struct datalink_proto *tmp, **clients = &p8022tr_list;
 119         unsigned long flags;
 120 
 121         save_flags(flags);
 122         cli();
 123 
 124         while ((tmp = *clients) != NULL)
 125         {
 126                 if (tmp->type[0] == type) {
 127                         *clients = tmp->next;
 128                         kfree_s(tmp, sizeof(struct datalink_proto));
 129                         break;
 130                 } else {
 131                         clients = &tmp->next;
 132                 }
 133         }
 134 
 135         restore_flags(flags);
 136 }
 137 

/* */