net/cor/kpacket_parse.c

   1 /*
   2  *      Connection oriented routing
   3  *      Copyright (C) 2007-2008 Michael Blizek
   4  *
   5  *      This program is free software; you can redistribute it and/or
   6  *      modify it under the terms of the GNU General Public License
   7  *      as published by the Free Software Foundation; either version 2
   8  *      of the License, or (at your option) any later version.
   9  *
  10  *      This program is distributed in the hope that it will be useful,
  11  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *      GNU General Public License for more details.
  14  *
  15  *      You should have received a copy of the GNU General Public License
  16  *      along with this program; if not, write to the Free Software
  17  *      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  *      02110-1301, USA.
  19  */
  20
  21 #include <asm/byteorder.h>
  22
  23 #include "cor.h"
  24
  25 /* not used, avoid compiler warning
  26  * static __u64 pull_u64(struct sk_buff *skb, int convbo)
  27 {
  28         char *ptr = cor_pull_skb(skb, 8);
  29
  30         __u64 ret = 0;
  31
  32         BUG_ON(0 == ptr);
  33
  34         ((char *)&ret)[0] = ptr[0];
  35         ((char *)&ret)[1] = ptr[1];
  36         ((char *)&ret)[2] = ptr[2];
  37         ((char *)&ret)[3] = ptr[3];
  38         ((char *)&ret)[4] = ptr[4];
  39         ((char *)&ret)[5] = ptr[5];
  40         ((char *)&ret)[6] = ptr[6];
  41         ((char *)&ret)[7] = ptr[7];
  42
  43         if (convbo)
  44                 return be64_to_cpu(ret);
  45         return ret;
  46 } */
  47
  48 static __u32 pull_u32(struct sk_buff *skb, int convbo)
  49 {
  50         char *ptr = cor_pull_skb(skb, 4);
  51
  52         __u32 ret = 0;
  53
  54         BUG_ON(0 == ptr);
  55
  56         ((char *)&ret)[0] = ptr[0];
  57         ((char *)&ret)[1] = ptr[1];
  58         ((char *)&ret)[2] = ptr[2];
  59         ((char *)&ret)[3] = ptr[3];
  60
  61         if (convbo)
  62                 return be32_to_cpu(ret);
  63         return ret;
  64 }
  65
  66 static __u16 pull_u16(struct sk_buff *skb, int convbo)
  67 {
  68         char *ptr = cor_pull_skb(skb, 2);
  69
  70         __u16 ret = 0;
  71
  72         BUG_ON(0 == ptr);
  73
  74         ((char *)&ret)[0] = ptr[0];
  75         ((char *)&ret)[1] = ptr[1];
  76
  77         if (convbo)
  78                 return be16_to_cpu(ret);
  79         return ret;
  80 }
  81
  82 /* not used, avoid compiler warning
  83  * static __u8 pull_u8(struct sk_buff *skb)
  84 {
  85         char *ptr = cor_pull_skb(skb, 1);
  86         BUG_ON(0 == ptr);
  87         return *ptr;
  88 } */
  89
  90 #warning todo
  91 static void parse_speed(struct neighbor *nb, struct sk_buff *skb,
  92                 __u8 code, struct conn *rconn)
  93 {
  94         __u16 speed = pull_u32(skb, 1);
  95 }
  96
  97 static void parse_conn_success(struct neighbor *nb, struct sk_buff *skb,
  98                 __u8 code, struct conn *rconn)
  99 {
 100         struct conn *sconn = rconn->reversedir;
 101
 102         __u32 conn_id = pull_u32(skb, 1);
 103
 104         BUG_ON(sconn == 0);
 105
 106         if (unlikely(unlikely(sconn->targettype != TARGET_OUT) ||
 107                         unlikely(sconn->target.out.nb != nb) ||
 108                         unlikely(sconn->target.out.conn_id != 0))) {
 109                 struct control_msg_out *cm = alloc_control_msg();
 110                 if (likely(cm != 0))
 111                         send_reset_conn(cm, nb, conn_id);
 112                 return;
 113         }
 114
 115         mutex_lock(&(sconn->rcv_lock));
 116         sconn->target.out.conn_id = conn_id;
 117         flush_out(sconn);
 118         mutex_unlock(&(sconn->rcv_lock));
 119 }
 120
 121 static void parse_reset(struct neighbor *nb, struct sk_buff *skb,
 122                 __u8 code, struct conn *rconn)
 123 {
 124         rconn->reversedir->isreset = 1;
 125         reset_conn(rconn);
 126 }
 127
 128 static void conn_cmd(struct neighbor *nb, struct sk_buff *skb, __u8 code,
 129                 void (*parsefunc)(struct neighbor *nb, struct sk_buff *skb,
 130                 __u8 code, struct conn *rconn))
 131 {
 132         __u32 conn_id = pull_u32(skb, 1);
 133         struct conn *rconn = get_conn(conn_id);
 134
 135         if (unlikely(rconn == 0))
 136                 return;
 137
 138         BUG_ON(SOURCE_IN != rconn->sourcetype);
 139         BUG_ON(0 == rconn->reversedir);
 140
 141         if (unlikely(rconn->source.in.nb != nb))
 142                 return;
 143
 144         parsefunc(nb, skb, code, rconn);
 145 }
 146
 147 static void parse_conndata(struct neighbor *nb, struct sk_buff *skb)
 148 {
 149         __u32 conn_id = pull_u32(skb, 1);
 150         __u32 seqno = pull_u32(skb, 1);
 151         __u16 datalength = pull_u16(skb, 1);
 152         char *data = cor_pull_skb(skb, datalength);
 153
 154         BUG_ON(data == 0);
 155
 156         conn_rcv_buildskb(data, datalength, conn_id, seqno);
 157 }
 158
 159 static void parse_connect(struct neighbor *nb, struct sk_buff *skb)
 160 {
 161         struct conn *rconn;
 162         __u32 conn_id = pull_u32(skb, 1);
 163         struct control_msg_out *cm = alloc_control_msg();
 164
 165         if (unlikely(cm == 0))
 166                 return;
 167
 168         rconn = alloc_conn(GFP_KERNEL);
 169
 170         if (unlikely(rconn == 0))
 171                 goto err;
 172
 173         if (conn_init_out(rconn->reversedir, nb))
 174                 goto err;
 175
 176         rconn->reversedir->target.out.conn_id = conn_id;
 177
 178         send_connect_success(cm, nb, rconn->reversedir->target.out.conn_id,
 179                         rconn->source.in.conn_id);
 180
 181         if (0) {
 182 err:
 183                 send_reset_conn(cm, nb, conn_id);
 184         }
 185 }
 186
 187 static void kernel_packet2(struct neighbor *nb, struct sk_buff *skb,
 188                 __u32 seqno)
 189 {
 190         struct control_msg_out *cm = alloc_control_msg();
 191         int ack = 0;
 192
 193         if (unlikely(cm == 0))
 194                 return;
 195
 196         while (1) {
 197                 struct control_msg_out *cm_tmp;
 198                 __u32 cookie;
 199                 __u32 respdelay;
 200
 201                 __u32 conn_id;
 202                 __u32 seqno;
 203
 204                 __u8 *codeptr = cor_pull_skb(skb, 1);
 205                 __u8 code;
 206
 207                 if (codeptr == 0)
 208                         break;
 209
 210                 code = *codeptr;
 211
 212                 switch (code) {
 213                 case KP_PADDING:
 214                         break;
 215                 case KP_PING:
 216                         cookie = pull_u32(skb, 0);
 217                         cm_tmp = alloc_control_msg();
 218                         if (likely(cm != 0)) {
 219                                 send_pong(cm_tmp, nb, cookie);
 220                         }
 221                         break;
 222                 case KP_PONG:
 223                         cookie = pull_u32(skb, 0);
 224                         respdelay = pull_u32(skb, 1);
 225                         ping_resp(nb, cookie, respdelay);
 226                         ack = 1;
 227                         break;
 228                 case KP_ACK:
 229                         conn_id = pull_u32(skb, 1);
 230                         seqno = pull_u32(skb, 1);
 231                         ack_received(nb, conn_id, seqno);
 232                         if (conn_id != 0)
 233                                 ack = 1;
 234                         break;
 235                 case KP_SPEED:
 236                         conn_cmd(nb, skb, code, parse_speed);
 237                         ack = 1;
 238                         break;
 239                 case KP_CONNECT:
 240                         parse_connect(nb, skb);
 241                         ack = 1;
 242                         break;
 243                 case KP_CONNECT_SUCCESS:
 244                         conn_cmd(nb, skb, code, parse_conn_success);
 245                         ack = 1;
 246                         break;
 247                 case KP_CONN_DATA:
 248                         parse_conndata(nb, skb);
 249                         ack = 1;
 250                         break;
 251                 case KP_RESET_CONN:
 252                         conn_cmd(nb, skb, code, parse_reset);
 253                         ack = 1;
 254                         break;
 255                 default:
 256                         BUG();
 257                 }
 258         }
 259
 260         if (ack)
 261                 send_ack(cm, nb, 0, seqno);
 262         else
 263                 free_control_msg(cm);
 264 }
 265
 266 void kernel_packet(struct neighbor *nb, struct sk_buff *skb, __u32 seqno)
 267 {
 268         struct sk_buff *skb2 = skb_clone(skb, __GFP_DMA | GFP_KERNEL);
 269
 270         while (1) {
 271                 __u8 *codeptr = cor_pull_skb(skb2, 1);
 272                 __u8 code;
 273
 274                 char *lengthptr;
 275                 __u32 length;
 276
 277                 if (codeptr == 0)
 278                         break;
 279                 code = *codeptr;
 280
 281                 switch (code) {
 282                 case KP_PADDING:
 283                         break;
 284                 case KP_PING:
 285                         if (cor_pull_skb(skb2, 4) == 0)
 286                                 goto discard;
 287                         break;
 288                 case KP_PONG:
 289                         if (cor_pull_skb(skb2, 8) == 0)
 290                                 goto discard;
 291                         break;
 292                 case KP_ACK:
 293                         if (cor_pull_skb(skb2, 8) == 0)
 294                                 goto discard;
 295                         break;
 296                 case KP_SPEED:
 297                         if (cor_pull_skb(skb2, 6) == 0)
 298                                 goto discard;
 299                         break;
 300                 case KP_CONNECT:
 301                         if (cor_pull_skb(skb2, 4) == 0)
 302                                 goto discard;
 303                         break;
 304                 case KP_CONNECT_SUCCESS:
 305                         if (cor_pull_skb(skb2, 8) == 0)
 306                                 goto discard;
 307                         break;
 308                 case KP_CONN_DATA:
 309                         if (cor_pull_skb(skb2, 8) == 0)
 310                                 goto discard;
 311                         lengthptr = cor_pull_skb(skb2, 2);
 312                         if (lengthptr == 0)
 313                                 goto discard;
 314                         length = ntohs(*((__u16 *)lengthptr));
 315                         if (cor_pull_skb(skb2, length) == 0)
 316                                 goto discard;
 317                         break;
 318                 case KP_RESET_CONN:
 319                         if (cor_pull_skb(skb2, 4) == 0)
 320                                 goto discard;
 321                         break;
 322                 default:
 323                         goto discard;
 324                 }
 325         }
 326         kfree_skb(skb2);
 327         kernel_packet2(nb, skb, seqno);
 328         kfree_skb(skb);
 329         return;
 330 discard:
 331         kfree_skb(skb2);
 332         kfree_skb(skb);
 333 }