| 1 | /* |
| 2 | * Copyright (c) University of British Columbia, 1984 |
| 3 | * Copyright (c) 1990 The Regents of the University of California. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * This code is derived from software contributed to Berkeley by |
| 7 | * the Laboratory for Computation Vision and the Computer Science Department |
| 8 | * of the University of British Columbia. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * 3. All advertising materials mentioning features or use of this software |
| 19 | * must display the following acknowledgement: |
| 20 | * This product includes software developed by the University of |
| 21 | * California, Berkeley and its contributors. |
| 22 | * 4. Neither the name of the University nor the names of its contributors |
| 23 | * may be used to endorse or promote products derived from this software |
| 24 | * without specific prior written permission. |
| 25 | * |
| 26 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 27 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 28 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 29 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 31 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 32 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 33 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 34 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 35 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 36 | * SUCH DAMAGE. |
| 37 | * |
| 38 | * from: @(#)pk_output.c 7.10 (Berkeley) 5/29/91 |
| 39 | * $Id$ |
| 40 | */ |
| 41 | |
| 42 | #include "param.h" |
| 43 | #include "systm.h" |
| 44 | #include "mbuf.h" |
| 45 | #include "socket.h" |
| 46 | #include "socketvar.h" |
| 47 | #include "protosw.h" |
| 48 | #include "errno.h" |
| 49 | |
| 50 | #include "../net/if.h" |
| 51 | |
| 52 | #include "x25.h" |
| 53 | #include "pk.h" |
| 54 | #include "pk_var.h" |
| 55 | |
| 56 | struct mbuf_cache pk_output_cache = {0 }; |
| 57 | struct mbuf *nextpk (); |
| 58 | |
| 59 | pk_output (lcp) |
| 60 | register struct pklcd *lcp; |
| 61 | { |
| 62 | register struct x25_packet *xp; |
| 63 | register struct mbuf *m; |
| 64 | register struct pkcb *pkp = lcp -> lcd_pkp; |
| 65 | |
| 66 | if (lcp == 0 || pkp == 0) { |
| 67 | printf ("pk_output: zero arg\n"); |
| 68 | return; |
| 69 | } |
| 70 | |
| 71 | while ((m = nextpk (lcp)) != NULL) { |
| 72 | xp = mtod (m, struct x25_packet *); |
| 73 | |
| 74 | switch (pk_decode (xp) + lcp -> lcd_state) { |
| 75 | /* |
| 76 | * All the work is already done - just set the state and |
| 77 | * pass to peer. |
| 78 | */ |
| 79 | case CALL + READY: |
| 80 | lcp -> lcd_state = SENT_CALL; |
| 81 | lcp -> lcd_timer = pk_t21; |
| 82 | break; |
| 83 | |
| 84 | /* |
| 85 | * Just set the state to allow packet to flow and send the |
| 86 | * confirmation. |
| 87 | */ |
| 88 | case CALL_ACCEPTED + RECEIVED_CALL: |
| 89 | lcp -> lcd_state = DATA_TRANSFER; |
| 90 | break; |
| 91 | |
| 92 | /* |
| 93 | * Just set the state. Keep the LCD around till the clear |
| 94 | * confirmation is returned. |
| 95 | */ |
| 96 | case CLEAR + RECEIVED_CALL: |
| 97 | case CLEAR + SENT_CALL: |
| 98 | case CLEAR + DATA_TRANSFER: |
| 99 | lcp -> lcd_state = SENT_CLEAR; |
| 100 | lcp -> lcd_retry = 0; |
| 101 | /* fall through */ |
| 102 | |
| 103 | case CLEAR + SENT_CLEAR: |
| 104 | lcp -> lcd_timer = pk_t23; |
| 105 | lcp -> lcd_retry++; |
| 106 | break; |
| 107 | |
| 108 | case CLEAR_CONF + RECEIVED_CLEAR: |
| 109 | case CLEAR_CONF + SENT_CLEAR: |
| 110 | case CLEAR_CONF + READY: |
| 111 | lcp -> lcd_state = READY; |
| 112 | break; |
| 113 | |
| 114 | case DATA + DATA_TRANSFER: |
| 115 | PS(xp) = lcp -> lcd_ssn; |
| 116 | lcp -> lcd_input_window = |
| 117 | (lcp -> lcd_rsn + 1) % MODULUS; |
| 118 | PR(xp) = lcp -> lcd_input_window; |
| 119 | lcp -> lcd_last_transmitted_pr = lcp -> lcd_input_window; |
| 120 | lcp -> lcd_ssn = (lcp -> lcd_ssn + 1) % MODULUS; |
| 121 | if (lcp -> lcd_ssn == ((lcp -> lcd_output_window + lcp -> lcd_windowsize) % MODULUS)) |
| 122 | lcp -> lcd_window_condition = TRUE; |
| 123 | break; |
| 124 | |
| 125 | case INTERRUPT + DATA_TRANSFER: |
| 126 | #ifdef ancient_history |
| 127 | xp -> packet_data = 0; |
| 128 | #endif |
| 129 | lcp -> lcd_intrconf_pending = TRUE; |
| 130 | break; |
| 131 | |
| 132 | case INTERRUPT_CONF + DATA_TRANSFER: |
| 133 | break; |
| 134 | |
| 135 | case RR + DATA_TRANSFER: |
| 136 | case RNR + DATA_TRANSFER: |
| 137 | lcp -> lcd_input_window = |
| 138 | (lcp -> lcd_rsn + 1) % MODULUS; |
| 139 | PR(xp) = lcp -> lcd_input_window; |
| 140 | lcp -> lcd_last_transmitted_pr = lcp -> lcd_input_window; |
| 141 | break; |
| 142 | |
| 143 | case RESET + DATA_TRANSFER: |
| 144 | lcp -> lcd_reset_condition = TRUE; |
| 145 | break; |
| 146 | |
| 147 | case RESET_CONF + DATA_TRANSFER: |
| 148 | lcp -> lcd_reset_condition = FALSE; |
| 149 | break; |
| 150 | |
| 151 | /* |
| 152 | * A restart should be only generated internally. Therefore |
| 153 | * all logic for restart is in the pk_restart routine. |
| 154 | */ |
| 155 | case RESTART + READY: |
| 156 | lcp -> lcd_timer = pk_t20; |
| 157 | break; |
| 158 | |
| 159 | /* |
| 160 | * Restarts are all handled internally. Therefore all the |
| 161 | * logic for the incoming restart packet is handled in the |
| 162 | * pk_input routine. |
| 163 | */ |
| 164 | case RESTART_CONF + READY: |
| 165 | break; |
| 166 | |
| 167 | default: |
| 168 | m_freem (m); |
| 169 | return; |
| 170 | } |
| 171 | |
| 172 | /* Trace the packet. */ |
| 173 | pk_trace (pkp -> pk_xcp, m, "P-Out"); |
| 174 | |
| 175 | /* Pass the packet on down to the link layer */ |
| 176 | if (pk_output_cache.mbc_size || pk_output_cache.mbc_oldsize) |
| 177 | mbuf_cache(&pk_output_cache, m); |
| 178 | (*pkp -> pk_lloutput) (pkp -> pk_llnext, m); |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | /* |
| 183 | * This procedure returns the next packet to send or null. A |
| 184 | * packet is composed of one or more mbufs. |
| 185 | */ |
| 186 | |
| 187 | struct mbuf * |
| 188 | nextpk (lcp) |
| 189 | struct pklcd *lcp; |
| 190 | { |
| 191 | register struct mbuf *m, *n; |
| 192 | struct socket *so = lcp -> lcd_so; |
| 193 | register struct sockbuf *sb = & (so ? so -> so_snd : lcp -> lcd_sb); |
| 194 | |
| 195 | if (lcp -> lcd_template) { |
| 196 | m = lcp -> lcd_template; |
| 197 | lcp -> lcd_template = NULL; |
| 198 | } else { |
| 199 | if (lcp -> lcd_rnr_condition || lcp -> lcd_window_condition || |
| 200 | lcp -> lcd_reset_condition) |
| 201 | return (NULL); |
| 202 | |
| 203 | if ((m = sb -> sb_mb) == 0) |
| 204 | return (NULL); |
| 205 | |
| 206 | sb -> sb_mb = m -> m_nextpkt; |
| 207 | m->m_act = 0; |
| 208 | for (n = m; n; n = n -> m_next) |
| 209 | sbfree (sb, n); |
| 210 | } |
| 211 | return (m); |
| 212 | } |