| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 |  | 
|  | 2 | /* | 
|  | 3 | * DECnet       An implementation of the DECnet protocol suite for the LINUX | 
|  | 4 | *              operating system.  DECnet is implemented using the  BSD Socket | 
|  | 5 | *              interface as the means of communication with the user level. | 
|  | 6 | * | 
|  | 7 | *              DECnet Network Services Protocol (Output) | 
|  | 8 | * | 
|  | 9 | * Author:      Eduardo Marcelo Serrat <emserrat@geocities.com> | 
|  | 10 | * | 
|  | 11 | * Changes: | 
|  | 12 | * | 
|  | 13 | *    Steve Whitehouse:  Split into dn_nsp_in.c and dn_nsp_out.c from | 
|  | 14 | *                       original dn_nsp.c. | 
|  | 15 | *    Steve Whitehouse:  Updated to work with my new routing architecture. | 
|  | 16 | *    Steve Whitehouse:  Added changes from Eduardo Serrat's patches. | 
|  | 17 | *    Steve Whitehouse:  Now conninits have the "return" bit set. | 
|  | 18 | *    Steve Whitehouse:  Fixes to check alloc'd skbs are non NULL! | 
|  | 19 | *                       Moved output state machine into one function | 
|  | 20 | *    Steve Whitehouse:  New output state machine | 
|  | 21 | *         Paul Koning:  Connect Confirm message fix. | 
|  | 22 | *      Eduardo Serrat:  Fix to stop dn_nsp_do_disc() sending malformed packets. | 
|  | 23 | *    Steve Whitehouse:  dn_nsp_output() and friends needed a spring clean | 
|  | 24 | *    Steve Whitehouse:  Moved dn_nsp_send() in here from route.h | 
|  | 25 | */ | 
|  | 26 |  | 
|  | 27 | /****************************************************************************** | 
|  | 28 | (c) 1995-1998 E.M. Serrat		emserrat@geocities.com | 
|  | 29 |  | 
|  | 30 | This program is free software; you can redistribute it and/or modify | 
|  | 31 | it under the terms of the GNU General Public License as published by | 
|  | 32 | the Free Software Foundation; either version 2 of the License, or | 
|  | 33 | any later version. | 
|  | 34 |  | 
|  | 35 | This program is distributed in the hope that it will be useful, | 
|  | 36 | but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | 37 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | 38 | GNU General Public License for more details. | 
|  | 39 | *******************************************************************************/ | 
|  | 40 |  | 
|  | 41 | #include <linux/errno.h> | 
|  | 42 | #include <linux/types.h> | 
|  | 43 | #include <linux/socket.h> | 
|  | 44 | #include <linux/in.h> | 
|  | 45 | #include <linux/kernel.h> | 
|  | 46 | #include <linux/sched.h> | 
|  | 47 | #include <linux/timer.h> | 
|  | 48 | #include <linux/string.h> | 
|  | 49 | #include <linux/sockios.h> | 
|  | 50 | #include <linux/net.h> | 
|  | 51 | #include <linux/netdevice.h> | 
|  | 52 | #include <linux/inet.h> | 
|  | 53 | #include <linux/route.h> | 
|  | 54 | #include <net/sock.h> | 
|  | 55 | #include <asm/system.h> | 
|  | 56 | #include <linux/fcntl.h> | 
|  | 57 | #include <linux/mm.h> | 
|  | 58 | #include <linux/termios.h> | 
|  | 59 | #include <linux/interrupt.h> | 
|  | 60 | #include <linux/proc_fs.h> | 
|  | 61 | #include <linux/stat.h> | 
|  | 62 | #include <linux/init.h> | 
|  | 63 | #include <linux/poll.h> | 
|  | 64 | #include <linux/if_packet.h> | 
|  | 65 | #include <net/neighbour.h> | 
|  | 66 | #include <net/dst.h> | 
|  | 67 | #include <net/flow.h> | 
|  | 68 | #include <net/dn.h> | 
|  | 69 | #include <net/dn_nsp.h> | 
|  | 70 | #include <net/dn_dev.h> | 
|  | 71 | #include <net/dn_route.h> | 
|  | 72 |  | 
|  | 73 |  | 
|  | 74 | static int nsp_backoff[NSP_MAXRXTSHIFT + 1] = { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 }; | 
|  | 75 |  | 
|  | 76 | static void dn_nsp_send(struct sk_buff *skb) | 
|  | 77 | { | 
|  | 78 | struct sock *sk = skb->sk; | 
|  | 79 | struct dn_scp *scp = DN_SK(sk); | 
|  | 80 | struct dst_entry *dst; | 
|  | 81 | struct flowi fl; | 
|  | 82 |  | 
|  | 83 | skb->h.raw = skb->data; | 
|  | 84 | scp->stamp = jiffies; | 
|  | 85 |  | 
|  | 86 | dst = sk_dst_check(sk, 0); | 
|  | 87 | if (dst) { | 
|  | 88 | try_again: | 
|  | 89 | skb->dst = dst; | 
|  | 90 | dst_output(skb); | 
|  | 91 | return; | 
|  | 92 | } | 
|  | 93 |  | 
|  | 94 | memset(&fl, 0, sizeof(fl)); | 
|  | 95 | fl.oif = sk->sk_bound_dev_if; | 
|  | 96 | fl.fld_src = dn_saddr2dn(&scp->addr); | 
|  | 97 | fl.fld_dst = dn_saddr2dn(&scp->peer); | 
|  | 98 | dn_sk_ports_copy(&fl, scp); | 
|  | 99 | fl.proto = DNPROTO_NSP; | 
|  | 100 | if (dn_route_output_sock(&sk->sk_dst_cache, &fl, sk, 0) == 0) { | 
|  | 101 | dst = sk_dst_get(sk); | 
|  | 102 | sk->sk_route_caps = dst->dev->features; | 
|  | 103 | goto try_again; | 
|  | 104 | } | 
|  | 105 |  | 
|  | 106 | sk->sk_err = EHOSTUNREACH; | 
|  | 107 | if (!sock_flag(sk, SOCK_DEAD)) | 
|  | 108 | sk->sk_state_change(sk); | 
|  | 109 | } | 
|  | 110 |  | 
|  | 111 |  | 
|  | 112 | /* | 
|  | 113 | * If sk == NULL, then we assume that we are supposed to be making | 
|  | 114 | * a routing layer skb. If sk != NULL, then we are supposed to be | 
|  | 115 | * creating an skb for the NSP layer. | 
|  | 116 | * | 
|  | 117 | * The eventual aim is for each socket to have a cached header size | 
|  | 118 | * for its outgoing packets, and to set hdr from this when sk != NULL. | 
|  | 119 | */ | 
|  | 120 | struct sk_buff *dn_alloc_skb(struct sock *sk, int size, int pri) | 
|  | 121 | { | 
|  | 122 | struct sk_buff *skb; | 
|  | 123 | int hdr = 64; | 
|  | 124 |  | 
|  | 125 | if ((skb = alloc_skb(size + hdr, pri)) == NULL) | 
|  | 126 | return NULL; | 
|  | 127 |  | 
|  | 128 | skb->protocol = __constant_htons(ETH_P_DNA_RT); | 
|  | 129 | skb->pkt_type = PACKET_OUTGOING; | 
|  | 130 |  | 
|  | 131 | if (sk) | 
|  | 132 | skb_set_owner_w(skb, sk); | 
|  | 133 |  | 
|  | 134 | skb_reserve(skb, hdr); | 
|  | 135 |  | 
|  | 136 | return skb; | 
|  | 137 | } | 
|  | 138 |  | 
|  | 139 | /* | 
|  | 140 | * Wrapper for the above, for allocs of data skbs. We try and get the | 
|  | 141 | * whole size thats been asked for (plus 11 bytes of header). If this | 
|  | 142 | * fails, then we try for any size over 16 bytes for SOCK_STREAMS. | 
|  | 143 | */ | 
|  | 144 | struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock, long timeo, int *err) | 
|  | 145 | { | 
|  | 146 | int space; | 
|  | 147 | int len; | 
|  | 148 | struct sk_buff *skb = NULL; | 
|  | 149 |  | 
|  | 150 | *err = 0; | 
|  | 151 |  | 
|  | 152 | while(skb == NULL) { | 
|  | 153 | if (signal_pending(current)) { | 
|  | 154 | *err = sock_intr_errno(timeo); | 
|  | 155 | break; | 
|  | 156 | } | 
|  | 157 |  | 
|  | 158 | if (sk->sk_shutdown & SEND_SHUTDOWN) { | 
|  | 159 | *err = EINVAL; | 
|  | 160 | break; | 
|  | 161 | } | 
|  | 162 |  | 
|  | 163 | if (sk->sk_err) | 
|  | 164 | break; | 
|  | 165 |  | 
|  | 166 | len = *size + 11; | 
|  | 167 | space = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); | 
|  | 168 |  | 
|  | 169 | if (space < len) { | 
|  | 170 | if ((sk->sk_socket->type == SOCK_STREAM) && | 
|  | 171 | (space >= (16 + 11))) | 
|  | 172 | len = space; | 
|  | 173 | } | 
|  | 174 |  | 
|  | 175 | if (space < len) { | 
|  | 176 | set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | 
|  | 177 | if (noblock) { | 
|  | 178 | *err = EWOULDBLOCK; | 
|  | 179 | break; | 
|  | 180 | } | 
|  | 181 |  | 
|  | 182 | clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); | 
|  | 183 | SOCK_SLEEP_PRE(sk) | 
|  | 184 |  | 
|  | 185 | if ((sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc)) < | 
|  | 186 | len) | 
|  | 187 | schedule(); | 
|  | 188 |  | 
|  | 189 | SOCK_SLEEP_POST(sk) | 
|  | 190 | continue; | 
|  | 191 | } | 
|  | 192 |  | 
|  | 193 | if ((skb = dn_alloc_skb(sk, len, sk->sk_allocation)) == NULL) | 
|  | 194 | continue; | 
|  | 195 |  | 
|  | 196 | *size = len - 11; | 
|  | 197 | } | 
|  | 198 |  | 
|  | 199 | return skb; | 
|  | 200 | } | 
|  | 201 |  | 
|  | 202 | /* | 
|  | 203 | * Calculate persist timer based upon the smoothed round | 
|  | 204 | * trip time and the variance. Backoff according to the | 
|  | 205 | * nsp_backoff[] array. | 
|  | 206 | */ | 
|  | 207 | unsigned long dn_nsp_persist(struct sock *sk) | 
|  | 208 | { | 
|  | 209 | struct dn_scp *scp = DN_SK(sk); | 
|  | 210 |  | 
|  | 211 | unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1; | 
|  | 212 |  | 
|  | 213 | t *= nsp_backoff[scp->nsp_rxtshift]; | 
|  | 214 |  | 
|  | 215 | if (t < HZ) t = HZ; | 
|  | 216 | if (t > (600*HZ)) t = (600*HZ); | 
|  | 217 |  | 
|  | 218 | if (scp->nsp_rxtshift < NSP_MAXRXTSHIFT) | 
|  | 219 | scp->nsp_rxtshift++; | 
|  | 220 |  | 
|  | 221 | /* printk(KERN_DEBUG "rxtshift %lu, t=%lu\n", scp->nsp_rxtshift, t); */ | 
|  | 222 |  | 
|  | 223 | return t; | 
|  | 224 | } | 
|  | 225 |  | 
|  | 226 | /* | 
|  | 227 | * This is called each time we get an estimate for the rtt | 
|  | 228 | * on the link. | 
|  | 229 | */ | 
|  | 230 | static void dn_nsp_rtt(struct sock *sk, long rtt) | 
|  | 231 | { | 
|  | 232 | struct dn_scp *scp = DN_SK(sk); | 
|  | 233 | long srtt = (long)scp->nsp_srtt; | 
|  | 234 | long rttvar = (long)scp->nsp_rttvar; | 
|  | 235 | long delta; | 
|  | 236 |  | 
|  | 237 | /* | 
|  | 238 | * If the jiffies clock flips over in the middle of timestamp | 
|  | 239 | * gathering this value might turn out negative, so we make sure | 
|  | 240 | * that is it always positive here. | 
|  | 241 | */ | 
|  | 242 | if (rtt < 0) | 
|  | 243 | rtt = -rtt; | 
|  | 244 | /* | 
|  | 245 | * Add new rtt to smoothed average | 
|  | 246 | */ | 
|  | 247 | delta = ((rtt << 3) - srtt); | 
|  | 248 | srtt += (delta >> 3); | 
|  | 249 | if (srtt >= 1) | 
|  | 250 | scp->nsp_srtt = (unsigned long)srtt; | 
|  | 251 | else | 
|  | 252 | scp->nsp_srtt = 1; | 
|  | 253 |  | 
|  | 254 | /* | 
|  | 255 | * Add new rtt varience to smoothed varience | 
|  | 256 | */ | 
|  | 257 | delta >>= 1; | 
|  | 258 | rttvar += ((((delta>0)?(delta):(-delta)) - rttvar) >> 2); | 
|  | 259 | if (rttvar >= 1) | 
|  | 260 | scp->nsp_rttvar = (unsigned long)rttvar; | 
|  | 261 | else | 
|  | 262 | scp->nsp_rttvar = 1; | 
|  | 263 |  | 
|  | 264 | /* printk(KERN_DEBUG "srtt=%lu rttvar=%lu\n", scp->nsp_srtt, scp->nsp_rttvar); */ | 
|  | 265 | } | 
|  | 266 |  | 
|  | 267 | /** | 
|  | 268 | * dn_nsp_clone_and_send - Send a data packet by cloning it | 
|  | 269 | * @skb: The packet to clone and transmit | 
|  | 270 | * @gfp: memory allocation flag | 
|  | 271 | * | 
|  | 272 | * Clone a queued data or other data packet and transmit it. | 
|  | 273 | * | 
|  | 274 | * Returns: The number of times the packet has been sent previously | 
|  | 275 | */ | 
|  | 276 | static inline unsigned dn_nsp_clone_and_send(struct sk_buff *skb, int gfp) | 
|  | 277 | { | 
|  | 278 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | 
|  | 279 | struct sk_buff *skb2; | 
|  | 280 | int ret = 0; | 
|  | 281 |  | 
|  | 282 | if ((skb2 = skb_clone(skb, gfp)) != NULL) { | 
|  | 283 | ret = cb->xmit_count; | 
|  | 284 | cb->xmit_count++; | 
|  | 285 | cb->stamp = jiffies; | 
|  | 286 | skb2->sk = skb->sk; | 
|  | 287 | dn_nsp_send(skb2); | 
|  | 288 | } | 
|  | 289 |  | 
|  | 290 | return ret; | 
|  | 291 | } | 
|  | 292 |  | 
|  | 293 | /** | 
|  | 294 | * dn_nsp_output - Try and send something from socket queues | 
|  | 295 | * @sk: The socket whose queues are to be investigated | 
|  | 296 | * @gfp: The memory allocation flags | 
|  | 297 | * | 
|  | 298 | * Try and send the packet on the end of the data and other data queues. | 
|  | 299 | * Other data gets priority over data, and if we retransmit a packet we | 
|  | 300 | * reduce the window by dividing it in two. | 
|  | 301 | * | 
|  | 302 | */ | 
|  | 303 | void dn_nsp_output(struct sock *sk) | 
|  | 304 | { | 
|  | 305 | struct dn_scp *scp = DN_SK(sk); | 
|  | 306 | struct sk_buff *skb; | 
|  | 307 | unsigned reduce_win = 0; | 
|  | 308 |  | 
|  | 309 | /* | 
|  | 310 | * First we check for otherdata/linkservice messages | 
|  | 311 | */ | 
|  | 312 | if ((skb = skb_peek(&scp->other_xmit_queue)) != NULL) | 
|  | 313 | reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC); | 
|  | 314 |  | 
|  | 315 | /* | 
|  | 316 | * If we may not send any data, we don't. | 
|  | 317 | * If we are still trying to get some other data down the | 
|  | 318 | * channel, we don't try and send any data. | 
|  | 319 | */ | 
|  | 320 | if (reduce_win || (scp->flowrem_sw != DN_SEND)) | 
|  | 321 | goto recalc_window; | 
|  | 322 |  | 
|  | 323 | if ((skb = skb_peek(&scp->data_xmit_queue)) != NULL) | 
|  | 324 | reduce_win = dn_nsp_clone_and_send(skb, GFP_ATOMIC); | 
|  | 325 |  | 
|  | 326 | /* | 
|  | 327 | * If we've sent any frame more than once, we cut the | 
|  | 328 | * send window size in half. There is always a minimum | 
|  | 329 | * window size of one available. | 
|  | 330 | */ | 
|  | 331 | recalc_window: | 
|  | 332 | if (reduce_win) { | 
|  | 333 | scp->snd_window >>= 1; | 
|  | 334 | if (scp->snd_window < NSP_MIN_WINDOW) | 
|  | 335 | scp->snd_window = NSP_MIN_WINDOW; | 
|  | 336 | } | 
|  | 337 | } | 
|  | 338 |  | 
|  | 339 | int dn_nsp_xmit_timeout(struct sock *sk) | 
|  | 340 | { | 
|  | 341 | struct dn_scp *scp = DN_SK(sk); | 
|  | 342 |  | 
|  | 343 | dn_nsp_output(sk); | 
|  | 344 |  | 
|  | 345 | if (skb_queue_len(&scp->data_xmit_queue) || skb_queue_len(&scp->other_xmit_queue)) | 
|  | 346 | scp->persist = dn_nsp_persist(sk); | 
|  | 347 |  | 
|  | 348 | return 0; | 
|  | 349 | } | 
|  | 350 |  | 
|  | 351 | static inline unsigned char *dn_mk_common_header(struct dn_scp *scp, struct sk_buff *skb, unsigned char msgflag, int len) | 
|  | 352 | { | 
|  | 353 | unsigned char *ptr = skb_push(skb, len); | 
|  | 354 |  | 
|  | 355 | BUG_ON(len < 5); | 
|  | 356 |  | 
|  | 357 | *ptr++ = msgflag; | 
|  | 358 | *((unsigned short *)ptr) = scp->addrrem; | 
|  | 359 | ptr += 2; | 
|  | 360 | *((unsigned short *)ptr) = scp->addrloc; | 
|  | 361 | ptr += 2; | 
|  | 362 | return ptr; | 
|  | 363 | } | 
|  | 364 |  | 
|  | 365 | static unsigned short *dn_mk_ack_header(struct sock *sk, struct sk_buff *skb, unsigned char msgflag, int hlen, int other) | 
|  | 366 | { | 
|  | 367 | struct dn_scp *scp = DN_SK(sk); | 
|  | 368 | unsigned short acknum = scp->numdat_rcv & 0x0FFF; | 
|  | 369 | unsigned short ackcrs = scp->numoth_rcv & 0x0FFF; | 
|  | 370 | unsigned short *ptr; | 
|  | 371 |  | 
|  | 372 | BUG_ON(hlen < 9); | 
|  | 373 |  | 
|  | 374 | scp->ackxmt_dat = acknum; | 
|  | 375 | scp->ackxmt_oth = ackcrs; | 
|  | 376 | acknum |= 0x8000; | 
|  | 377 | ackcrs |= 0x8000; | 
|  | 378 |  | 
|  | 379 | /* If this is an "other data/ack" message, swap acknum and ackcrs */ | 
|  | 380 | if (other) { | 
|  | 381 | unsigned short tmp = acknum; | 
|  | 382 | acknum = ackcrs; | 
|  | 383 | ackcrs = tmp; | 
|  | 384 | } | 
|  | 385 |  | 
|  | 386 | /* Set "cross subchannel" bit in ackcrs */ | 
|  | 387 | ackcrs |= 0x2000; | 
|  | 388 |  | 
|  | 389 | ptr = (unsigned short *)dn_mk_common_header(scp, skb, msgflag, hlen); | 
|  | 390 |  | 
|  | 391 | *ptr++ = dn_htons(acknum); | 
|  | 392 | *ptr++ = dn_htons(ackcrs); | 
|  | 393 |  | 
|  | 394 | return ptr; | 
|  | 395 | } | 
|  | 396 |  | 
|  | 397 | static unsigned short *dn_nsp_mk_data_header(struct sock *sk, struct sk_buff *skb, int oth) | 
|  | 398 | { | 
|  | 399 | struct dn_scp *scp = DN_SK(sk); | 
|  | 400 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | 
|  | 401 | unsigned short *ptr = dn_mk_ack_header(sk, skb, cb->nsp_flags, 11, oth); | 
|  | 402 |  | 
|  | 403 | if (unlikely(oth)) { | 
|  | 404 | cb->segnum = scp->numoth; | 
|  | 405 | seq_add(&scp->numoth, 1); | 
|  | 406 | } else { | 
|  | 407 | cb->segnum = scp->numdat; | 
|  | 408 | seq_add(&scp->numdat, 1); | 
|  | 409 | } | 
|  | 410 | *(ptr++) = dn_htons(cb->segnum); | 
|  | 411 |  | 
|  | 412 | return ptr; | 
|  | 413 | } | 
|  | 414 |  | 
|  | 415 | void dn_nsp_queue_xmit(struct sock *sk, struct sk_buff *skb, int gfp, int oth) | 
|  | 416 | { | 
|  | 417 | struct dn_scp *scp = DN_SK(sk); | 
|  | 418 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | 
|  | 419 | unsigned long t = ((scp->nsp_srtt >> 2) + scp->nsp_rttvar) >> 1; | 
|  | 420 |  | 
|  | 421 | cb->xmit_count = 0; | 
|  | 422 | dn_nsp_mk_data_header(sk, skb, oth); | 
|  | 423 |  | 
|  | 424 | /* | 
|  | 425 | * Slow start: If we have been idle for more than | 
|  | 426 | * one RTT, then reset window to min size. | 
|  | 427 | */ | 
|  | 428 | if ((jiffies - scp->stamp) > t) | 
|  | 429 | scp->snd_window = NSP_MIN_WINDOW; | 
|  | 430 |  | 
|  | 431 | if (oth) | 
|  | 432 | skb_queue_tail(&scp->other_xmit_queue, skb); | 
|  | 433 | else | 
|  | 434 | skb_queue_tail(&scp->data_xmit_queue, skb); | 
|  | 435 |  | 
|  | 436 | if (scp->flowrem_sw != DN_SEND) | 
|  | 437 | return; | 
|  | 438 |  | 
|  | 439 | dn_nsp_clone_and_send(skb, gfp); | 
|  | 440 | } | 
|  | 441 |  | 
|  | 442 |  | 
|  | 443 | int dn_nsp_check_xmit_queue(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *q, unsigned short acknum) | 
|  | 444 | { | 
|  | 445 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | 
|  | 446 | struct dn_scp *scp = DN_SK(sk); | 
|  | 447 | struct sk_buff *skb2, *list, *ack = NULL; | 
|  | 448 | int wakeup = 0; | 
|  | 449 | int try_retrans = 0; | 
|  | 450 | unsigned long reftime = cb->stamp; | 
|  | 451 | unsigned long pkttime; | 
|  | 452 | unsigned short xmit_count; | 
|  | 453 | unsigned short segnum; | 
|  | 454 |  | 
|  | 455 | skb2 = q->next; | 
|  | 456 | list = (struct sk_buff *)q; | 
|  | 457 | while(list != skb2) { | 
|  | 458 | struct dn_skb_cb *cb2 = DN_SKB_CB(skb2); | 
|  | 459 |  | 
|  | 460 | if (dn_before_or_equal(cb2->segnum, acknum)) | 
|  | 461 | ack = skb2; | 
|  | 462 |  | 
|  | 463 | /* printk(KERN_DEBUG "ack: %s %04x %04x\n", ack ? "ACK" : "SKIP", (int)cb2->segnum, (int)acknum); */ | 
|  | 464 |  | 
|  | 465 | skb2 = skb2->next; | 
|  | 466 |  | 
|  | 467 | if (ack == NULL) | 
|  | 468 | continue; | 
|  | 469 |  | 
|  | 470 | /* printk(KERN_DEBUG "check_xmit_queue: %04x, %d\n", acknum, cb2->xmit_count); */ | 
|  | 471 |  | 
|  | 472 | /* Does _last_ packet acked have xmit_count > 1 */ | 
|  | 473 | try_retrans = 0; | 
|  | 474 | /* Remember to wake up the sending process */ | 
|  | 475 | wakeup = 1; | 
|  | 476 | /* Keep various statistics */ | 
|  | 477 | pkttime = cb2->stamp; | 
|  | 478 | xmit_count = cb2->xmit_count; | 
|  | 479 | segnum = cb2->segnum; | 
|  | 480 | /* Remove and drop ack'ed packet */ | 
|  | 481 | skb_unlink(ack); | 
|  | 482 | kfree_skb(ack); | 
|  | 483 | ack = NULL; | 
|  | 484 |  | 
|  | 485 | /* | 
|  | 486 | * We don't expect to see acknowledgements for packets we | 
|  | 487 | * haven't sent yet. | 
|  | 488 | */ | 
|  | 489 | WARN_ON(xmit_count == 0); | 
|  | 490 |  | 
|  | 491 | /* | 
|  | 492 | * If the packet has only been sent once, we can use it | 
|  | 493 | * to calculate the RTT and also open the window a little | 
|  | 494 | * further. | 
|  | 495 | */ | 
|  | 496 | if (xmit_count == 1) { | 
|  | 497 | if (dn_equal(segnum, acknum)) | 
|  | 498 | dn_nsp_rtt(sk, (long)(pkttime - reftime)); | 
|  | 499 |  | 
|  | 500 | if (scp->snd_window < scp->max_window) | 
|  | 501 | scp->snd_window++; | 
|  | 502 | } | 
|  | 503 |  | 
|  | 504 | /* | 
|  | 505 | * Packet has been sent more than once. If this is the last | 
|  | 506 | * packet to be acknowledged then we want to send the next | 
|  | 507 | * packet in the send queue again (assumes the remote host does | 
|  | 508 | * go-back-N error control). | 
|  | 509 | */ | 
|  | 510 | if (xmit_count > 1) | 
|  | 511 | try_retrans = 1; | 
|  | 512 | } | 
|  | 513 |  | 
|  | 514 | if (try_retrans) | 
|  | 515 | dn_nsp_output(sk); | 
|  | 516 |  | 
|  | 517 | return wakeup; | 
|  | 518 | } | 
|  | 519 |  | 
|  | 520 | void dn_nsp_send_data_ack(struct sock *sk) | 
|  | 521 | { | 
|  | 522 | struct sk_buff *skb = NULL; | 
|  | 523 |  | 
|  | 524 | if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL) | 
|  | 525 | return; | 
|  | 526 |  | 
|  | 527 | skb_reserve(skb, 9); | 
|  | 528 | dn_mk_ack_header(sk, skb, 0x04, 9, 0); | 
|  | 529 | dn_nsp_send(skb); | 
|  | 530 | } | 
|  | 531 |  | 
|  | 532 | void dn_nsp_send_oth_ack(struct sock *sk) | 
|  | 533 | { | 
|  | 534 | struct sk_buff *skb = NULL; | 
|  | 535 |  | 
|  | 536 | if ((skb = dn_alloc_skb(sk, 9, GFP_ATOMIC)) == NULL) | 
|  | 537 | return; | 
|  | 538 |  | 
|  | 539 | skb_reserve(skb, 9); | 
|  | 540 | dn_mk_ack_header(sk, skb, 0x14, 9, 1); | 
|  | 541 | dn_nsp_send(skb); | 
|  | 542 | } | 
|  | 543 |  | 
|  | 544 |  | 
|  | 545 | void dn_send_conn_ack (struct sock *sk) | 
|  | 546 | { | 
|  | 547 | struct dn_scp *scp = DN_SK(sk); | 
|  | 548 | struct sk_buff *skb = NULL; | 
|  | 549 | struct nsp_conn_ack_msg *msg; | 
|  | 550 |  | 
|  | 551 | if ((skb = dn_alloc_skb(sk, 3, sk->sk_allocation)) == NULL) | 
|  | 552 | return; | 
|  | 553 |  | 
|  | 554 | msg = (struct nsp_conn_ack_msg *)skb_put(skb, 3); | 
|  | 555 | msg->msgflg = 0x24; | 
|  | 556 | msg->dstaddr = scp->addrrem; | 
|  | 557 |  | 
|  | 558 | dn_nsp_send(skb); | 
|  | 559 | } | 
|  | 560 |  | 
|  | 561 | void dn_nsp_delayed_ack(struct sock *sk) | 
|  | 562 | { | 
|  | 563 | struct dn_scp *scp = DN_SK(sk); | 
|  | 564 |  | 
|  | 565 | if (scp->ackxmt_oth != scp->numoth_rcv) | 
|  | 566 | dn_nsp_send_oth_ack(sk); | 
|  | 567 |  | 
|  | 568 | if (scp->ackxmt_dat != scp->numdat_rcv) | 
|  | 569 | dn_nsp_send_data_ack(sk); | 
|  | 570 | } | 
|  | 571 |  | 
|  | 572 | static int dn_nsp_retrans_conn_conf(struct sock *sk) | 
|  | 573 | { | 
|  | 574 | struct dn_scp *scp = DN_SK(sk); | 
|  | 575 |  | 
|  | 576 | if (scp->state == DN_CC) | 
|  | 577 | dn_send_conn_conf(sk, GFP_ATOMIC); | 
|  | 578 |  | 
|  | 579 | return 0; | 
|  | 580 | } | 
|  | 581 |  | 
|  | 582 | void dn_send_conn_conf(struct sock *sk, int gfp) | 
|  | 583 | { | 
|  | 584 | struct dn_scp *scp = DN_SK(sk); | 
|  | 585 | struct sk_buff *skb = NULL; | 
|  | 586 | struct nsp_conn_init_msg *msg; | 
|  | 587 | unsigned char len = scp->conndata_out.opt_optl; | 
|  | 588 |  | 
|  | 589 | if ((skb = dn_alloc_skb(sk, 50 + scp->conndata_out.opt_optl, gfp)) == NULL) | 
|  | 590 | return; | 
|  | 591 |  | 
|  | 592 | msg = (struct nsp_conn_init_msg *)skb_put(skb, sizeof(*msg)); | 
|  | 593 | msg->msgflg = 0x28; | 
|  | 594 | msg->dstaddr = scp->addrrem; | 
|  | 595 | msg->srcaddr = scp->addrloc; | 
|  | 596 | msg->services = scp->services_loc; | 
|  | 597 | msg->info = scp->info_loc; | 
|  | 598 | msg->segsize = dn_htons(scp->segsize_loc); | 
|  | 599 |  | 
|  | 600 | *skb_put(skb,1) = len; | 
|  | 601 |  | 
|  | 602 | if (len > 0) | 
|  | 603 | memcpy(skb_put(skb, len), scp->conndata_out.opt_data, len); | 
|  | 604 |  | 
|  | 605 |  | 
|  | 606 | dn_nsp_send(skb); | 
|  | 607 |  | 
|  | 608 | scp->persist = dn_nsp_persist(sk); | 
|  | 609 | scp->persist_fxn = dn_nsp_retrans_conn_conf; | 
|  | 610 | } | 
|  | 611 |  | 
|  | 612 |  | 
|  | 613 | static __inline__ void dn_nsp_do_disc(struct sock *sk, unsigned char msgflg, | 
|  | 614 | unsigned short reason, int gfp, struct dst_entry *dst, | 
|  | 615 | int ddl, unsigned char *dd, __u16 rem, __u16 loc) | 
|  | 616 | { | 
|  | 617 | struct sk_buff *skb = NULL; | 
|  | 618 | int size = 7 + ddl + ((msgflg == NSP_DISCINIT) ? 1 : 0); | 
|  | 619 | unsigned char *msg; | 
|  | 620 |  | 
|  | 621 | if ((dst == NULL) || (rem == 0)) { | 
|  | 622 | if (net_ratelimit()) | 
|  | 623 | printk(KERN_DEBUG "DECnet: dn_nsp_do_disc: BUG! Please report this to SteveW@ACM.org rem=%u dst=%p\n", (unsigned)rem, dst); | 
|  | 624 | return; | 
|  | 625 | } | 
|  | 626 |  | 
|  | 627 | if ((skb = dn_alloc_skb(sk, size, gfp)) == NULL) | 
|  | 628 | return; | 
|  | 629 |  | 
|  | 630 | msg = skb_put(skb, size); | 
|  | 631 | *msg++ = msgflg; | 
|  | 632 | *(__u16 *)msg = rem; | 
|  | 633 | msg += 2; | 
|  | 634 | *(__u16 *)msg = loc; | 
|  | 635 | msg += 2; | 
|  | 636 | *(__u16 *)msg = dn_htons(reason); | 
|  | 637 | msg += 2; | 
|  | 638 | if (msgflg == NSP_DISCINIT) | 
|  | 639 | *msg++ = ddl; | 
|  | 640 |  | 
|  | 641 | if (ddl) { | 
|  | 642 | memcpy(msg, dd, ddl); | 
|  | 643 | } | 
|  | 644 |  | 
|  | 645 | /* | 
|  | 646 | * This doesn't go via the dn_nsp_send() function since we need | 
|  | 647 | * to be able to send disc packets out which have no socket | 
|  | 648 | * associations. | 
|  | 649 | */ | 
|  | 650 | skb->dst = dst_clone(dst); | 
|  | 651 | dst_output(skb); | 
|  | 652 | } | 
|  | 653 |  | 
|  | 654 |  | 
|  | 655 | void dn_nsp_send_disc(struct sock *sk, unsigned char msgflg, | 
|  | 656 | unsigned short reason, int gfp) | 
|  | 657 | { | 
|  | 658 | struct dn_scp *scp = DN_SK(sk); | 
|  | 659 | int ddl = 0; | 
|  | 660 |  | 
|  | 661 | if (msgflg == NSP_DISCINIT) | 
|  | 662 | ddl = scp->discdata_out.opt_optl; | 
|  | 663 |  | 
|  | 664 | if (reason == 0) | 
|  | 665 | reason = scp->discdata_out.opt_status; | 
|  | 666 |  | 
|  | 667 | dn_nsp_do_disc(sk, msgflg, reason, gfp, sk->sk_dst_cache, ddl, | 
|  | 668 | scp->discdata_out.opt_data, scp->addrrem, scp->addrloc); | 
|  | 669 | } | 
|  | 670 |  | 
|  | 671 |  | 
|  | 672 | void dn_nsp_return_disc(struct sk_buff *skb, unsigned char msgflg, | 
|  | 673 | unsigned short reason) | 
|  | 674 | { | 
|  | 675 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | 
|  | 676 | int ddl = 0; | 
|  | 677 | int gfp = GFP_ATOMIC; | 
|  | 678 |  | 
|  | 679 | dn_nsp_do_disc(NULL, msgflg, reason, gfp, skb->dst, ddl, | 
|  | 680 | NULL, cb->src_port, cb->dst_port); | 
|  | 681 | } | 
|  | 682 |  | 
|  | 683 |  | 
|  | 684 | void dn_nsp_send_link(struct sock *sk, unsigned char lsflags, char fcval) | 
|  | 685 | { | 
|  | 686 | struct dn_scp *scp = DN_SK(sk); | 
|  | 687 | struct sk_buff *skb; | 
|  | 688 | unsigned char *ptr; | 
|  | 689 | int gfp = GFP_ATOMIC; | 
|  | 690 |  | 
|  | 691 | if ((skb = dn_alloc_skb(sk, DN_MAX_NSP_DATA_HEADER + 2, gfp)) == NULL) | 
|  | 692 | return; | 
|  | 693 |  | 
|  | 694 | skb_reserve(skb, DN_MAX_NSP_DATA_HEADER); | 
|  | 695 | ptr = skb_put(skb, 2); | 
|  | 696 | DN_SKB_CB(skb)->nsp_flags = 0x10; | 
|  | 697 | *ptr++ = lsflags; | 
|  | 698 | *ptr = fcval; | 
|  | 699 |  | 
|  | 700 | dn_nsp_queue_xmit(sk, skb, gfp, 1); | 
|  | 701 |  | 
|  | 702 | scp->persist = dn_nsp_persist(sk); | 
|  | 703 | scp->persist_fxn = dn_nsp_xmit_timeout; | 
|  | 704 | } | 
|  | 705 |  | 
|  | 706 | static int dn_nsp_retrans_conninit(struct sock *sk) | 
|  | 707 | { | 
|  | 708 | struct dn_scp *scp = DN_SK(sk); | 
|  | 709 |  | 
|  | 710 | if (scp->state == DN_CI) | 
|  | 711 | dn_nsp_send_conninit(sk, NSP_RCI); | 
|  | 712 |  | 
|  | 713 | return 0; | 
|  | 714 | } | 
|  | 715 |  | 
|  | 716 | void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg) | 
|  | 717 | { | 
|  | 718 | struct dn_scp *scp = DN_SK(sk); | 
|  | 719 | struct nsp_conn_init_msg *msg; | 
|  | 720 | unsigned char aux; | 
|  | 721 | unsigned char menuver; | 
|  | 722 | struct dn_skb_cb *cb; | 
|  | 723 | unsigned char type = 1; | 
|  | 724 | int allocation = (msgflg == NSP_CI) ? sk->sk_allocation : GFP_ATOMIC; | 
|  | 725 | struct sk_buff *skb = dn_alloc_skb(sk, 200, allocation); | 
|  | 726 |  | 
|  | 727 | if (!skb) | 
|  | 728 | return; | 
|  | 729 |  | 
|  | 730 | cb  = DN_SKB_CB(skb); | 
|  | 731 | msg = (struct nsp_conn_init_msg *)skb_put(skb,sizeof(*msg)); | 
|  | 732 |  | 
|  | 733 | msg->msgflg	= msgflg; | 
|  | 734 | msg->dstaddr	= 0x0000;		/* Remote Node will assign it*/ | 
|  | 735 |  | 
|  | 736 | msg->srcaddr	= scp->addrloc; | 
|  | 737 | msg->services	= scp->services_loc;	/* Requested flow control    */ | 
|  | 738 | msg->info	= scp->info_loc;	/* Version Number            */ | 
|  | 739 | msg->segsize	= dn_htons(scp->segsize_loc);	/* Max segment size  */ | 
|  | 740 |  | 
|  | 741 | if (scp->peer.sdn_objnum) | 
|  | 742 | type = 0; | 
|  | 743 |  | 
|  | 744 | skb_put(skb, dn_sockaddr2username(&scp->peer, skb->tail, type)); | 
|  | 745 | skb_put(skb, dn_sockaddr2username(&scp->addr, skb->tail, 2)); | 
|  | 746 |  | 
|  | 747 | menuver = DN_MENUVER_ACC | DN_MENUVER_USR; | 
|  | 748 | if (scp->peer.sdn_flags & SDF_PROXY) | 
|  | 749 | menuver |= DN_MENUVER_PRX; | 
|  | 750 | if (scp->peer.sdn_flags & SDF_UICPROXY) | 
|  | 751 | menuver |= DN_MENUVER_UIC; | 
|  | 752 |  | 
|  | 753 | *skb_put(skb, 1) = menuver;	/* Menu Version		*/ | 
|  | 754 |  | 
|  | 755 | aux = scp->accessdata.acc_userl; | 
|  | 756 | *skb_put(skb, 1) = aux; | 
|  | 757 | if (aux > 0) | 
|  | 758 | memcpy(skb_put(skb, aux), scp->accessdata.acc_user, aux); | 
|  | 759 |  | 
|  | 760 | aux = scp->accessdata.acc_passl; | 
|  | 761 | *skb_put(skb, 1) = aux; | 
|  | 762 | if (aux > 0) | 
|  | 763 | memcpy(skb_put(skb, aux), scp->accessdata.acc_pass, aux); | 
|  | 764 |  | 
|  | 765 | aux = scp->accessdata.acc_accl; | 
|  | 766 | *skb_put(skb, 1) = aux; | 
|  | 767 | if (aux > 0) | 
|  | 768 | memcpy(skb_put(skb, aux), scp->accessdata.acc_acc, aux); | 
|  | 769 |  | 
|  | 770 | aux = scp->conndata_out.opt_optl; | 
|  | 771 | *skb_put(skb, 1) = aux; | 
|  | 772 | if (aux > 0) | 
|  | 773 | memcpy(skb_put(skb,aux), scp->conndata_out.opt_data, aux); | 
|  | 774 |  | 
|  | 775 | scp->persist = dn_nsp_persist(sk); | 
|  | 776 | scp->persist_fxn = dn_nsp_retrans_conninit; | 
|  | 777 |  | 
|  | 778 | cb->rt_flags = DN_RT_F_RQR; | 
|  | 779 |  | 
|  | 780 | dn_nsp_send(skb); | 
|  | 781 | } | 
|  | 782 |  |