| 1 | /* nsp_input.c 1.2 82/05/15 */ |
| 2 | |
| 3 | #include "../h/param.h" |
| 4 | #include "../h/systm.h" |
| 5 | #include "../h/mbuf.h" |
| 6 | #include "../h/protosw.h" |
| 7 | #include "../h/socket.h" |
| 8 | #include "../h/socketvar.h" |
| 9 | #include "../net/dn_systm.h" |
| 10 | #include "../net/nsp.h" |
| 11 | #include "../net/nsp_var.h" |
| 12 | #include "../errno.h" |
| 13 | |
| 14 | int nspidebug = 1; |
| 15 | #define printd if(nspidebug)printf |
| 16 | /* |
| 17 | * NSP input routine: decode incoming packet and dispatch |
| 18 | * to appropriate socket. Called from the software interrupt |
| 19 | * at splnet. |
| 20 | * |
| 21 | * TODO: |
| 22 | * count occurances of various error conditions. |
| 23 | */ |
| 24 | |
| 25 | nspintr() |
| 26 | { |
| 27 | struct mbuf *m; |
| 28 | struct tprh *t; |
| 29 | int s, bom, eom; |
| 30 | u_short srcnode; |
| 31 | char *p; |
| 32 | struct nspcb *np; |
| 33 | |
| 34 | /* |
| 35 | * Loop pulling packets off the interrupt queue. |
| 36 | */ |
| 37 | next: |
| 38 | s = splimp(); |
| 39 | IF_DEQUEUE(&nspintrq, m); |
| 40 | splx(s); |
| 41 | printd("nsp_input: m 0x%x", m); |
| 42 | if (m == 0) |
| 43 | return; |
| 44 | t = mtod(m, struct tprh *); |
| 45 | srcnode = t->tprh_srcnode; |
| 46 | m->m_len -= sizeof (struct tprh); /* use m_adj??? */ |
| 47 | m->m_off += sizeof (struct tprh); |
| 48 | printd(", srcnode %d, len %d", srcnode, m->m_len); |
| 49 | if (m->m_len <= 0) { |
| 50 | m_freem(m); |
| 51 | goto next; |
| 52 | } |
| 53 | |
| 54 | /* |
| 55 | * Switch on the type of the message. |
| 56 | */ |
| 57 | p = mtod(m, char *); |
| 58 | switch (*p) { |
| 59 | |
| 60 | /* |
| 61 | * Got a Data message, possibly with EOM and |
| 62 | * BOM flags set. Call nsp_chkaddr to do ack |
| 63 | * and flow controll processing, then pass the |
| 64 | * data to the user. |
| 65 | */ |
| 66 | case NSP_DATA|NSP_EOM|NSP_BOM: |
| 67 | eom = bom = 1; |
| 68 | goto data; |
| 69 | |
| 70 | case NSP_DATA|NSP_EOM: |
| 71 | eom = 1; |
| 72 | goto data; |
| 73 | |
| 74 | case NSP_DATA|NSP_BOM: |
| 75 | bom = 1; |
| 76 | |
| 77 | case NSP_DATA: |
| 78 | data: |
| 79 | printd(", DATA (%d,%d)", bom, eom); |
| 80 | np = nsp_chkaddr(m, srcnode, NSP_DATA, &segnum); |
| 81 | if (np == 0) { |
| 82 | m_freem(m); |
| 83 | goto next; |
| 84 | } |
| 85 | |
| 86 | /* |
| 87 | * Data messages only valid in Run state |
| 88 | */ |
| 89 | if (np->n_state != NS_RUN) { |
| 90 | printf(", !RUN (%d)\n", np->n_state); |
| 91 | m_freem(m); |
| 92 | goto next; |
| 93 | } |
| 94 | if (SEQ_GTR(segnum, np->na_xmtdat)) { |
| 95 | /* SHOULD DO SEGMENT RECONSTRUCTION HERE */ |
| 96 | printd(", got data!"); |
| 97 | sbpappend(m, &np->n_socket->sb_rcv); |
| 98 | } else |
| 99 | np->n_flags |= NF_DATACK; |
| 100 | break; |
| 101 | |
| 102 | /* |
| 103 | * Got an interrupt message. Call nsp_chkaddr |
| 104 | * (as usual). Save the interrupt data for the |
| 105 | * user. |
| 106 | * GENERATE A SIGNAL OF SOME SORT??? |
| 107 | */ |
| 108 | case NSP_INTR: |
| 109 | printd(", INTR"); |
| 110 | np = nsp_chkaddr(m, srcnode, NSP_INTR, &segnum); |
| 111 | if (np == 0) { |
| 112 | m_freem(m); |
| 113 | goto next; |
| 114 | } |
| 115 | |
| 116 | /* |
| 117 | * If we are in the Connect Confirm state then |
| 118 | * this Interrupt packet causes the transition |
| 119 | * to the Run state. Otherwise we better be in |
| 120 | * the Run state already. |
| 121 | */ |
| 122 | if (np->n_state == NS_CC) |
| 123 | np->n_state = NS_RUN; |
| 124 | else if (np->n_state != NS_RUN) { |
| 125 | printf(", !RUN %d\n", np->n_state); |
| 126 | m_freem(m); |
| 127 | goto next; |
| 128 | } |
| 129 | |
| 130 | /* |
| 131 | * If this segment is the one after the last |
| 132 | * other data segment we acked, and there is |
| 133 | * no waiting interrupt message, then queue |
| 134 | * this one up. |
| 135 | */ |
| 136 | if (segnum == SEQ_ADD(np->na_xmtoth, 1) && |
| 137 | np->nf_locint == NFL_EMPTY) { |
| 138 | if (np->nb_rcv) { |
| 139 | printd(", flush old intr data"); |
| 140 | m_freem(np->nb_rcv); |
| 141 | } |
| 142 | if (m->m_len > 16) { |
| 143 | printd(", intr data too long\n"); |
| 144 | m_freem(m); |
| 145 | goto next; |
| 146 | } |
| 147 | np->nb_rcv = m; |
| 148 | np->nf_locint = NFL_INTR; |
| 149 | np->na_xmtoth = segnum; /* really += 1 */ |
| 150 | np->n_flags |= NF_OTHACK; |
| 151 | } else if (SEQ_LEQ(segnum, np->na_xmtoth)) |
| 152 | np->n_flags |= NF_OTHACK; |
| 153 | break; |
| 154 | |
| 155 | /* |
| 156 | * Got a Link Service message. Process options |
| 157 | * to modify flow control values. |
| 158 | */ |
| 159 | case NSP_LS: |
| 160 | printd(", LS"); |
| 161 | np = nsp_chkaddr(m, srcnode, NSP_LS, &segnum); |
| 162 | if (np == 0) { |
| 163 | m_freem(m); |
| 164 | goto next; |
| 165 | } |
| 166 | |
| 167 | /* |
| 168 | * If we are in the Connect Confirm state then |
| 169 | * this Link Service packet causes the transition |
| 170 | * to the Run state. Otherwise we better be in |
| 171 | * the Run state already. |
| 172 | */ |
| 173 | if (np->n_state == NS_CC) |
| 174 | np->n_state = NS_RUN; |
| 175 | else if (np->n_state != NS_RUN) { |
| 176 | printd(", !RUN %d\n", np->n_state); |
| 177 | m_freem(m); |
| 178 | goto next; |
| 179 | } |
| 180 | p = mtod(m, char *); |
| 181 | lsf = *p++; |
| 182 | fcval = *p; |
| 183 | printd(", lsf 0x%x, fcval %d", lsf, fcval); |
| 184 | switch (lsf & NSPLS_FCVALINT) { |
| 185 | case NSPLS_DATREQ: |
| 186 | if (seqnum == SEQ_ADD(np->na_xmtoth, 1)) { |
| 187 | if (np->nf_remdat + fcval >= -128 && |
| 188 | np->nf_remdat + fcval <= 127) { |
| 189 | np->nf_remdat += fcval; |
| 190 | np->na_xmtoth = segnum; |
| 191 | np->n_flags |= NF_OTHACK; |
| 192 | switch (lsf & NSPLS_FCMOD) { |
| 193 | case NSPLS_NOCHANGE: |
| 194 | break; |
| 195 | case NSPLS_ON: |
| 196 | np->n_flags &= ~NF_DATOFF; |
| 197 | break; |
| 198 | case NSPLS_OFF: |
| 199 | np->n_flags |= NF_DATOFF; |
| 200 | break; |
| 201 | default: |
| 202 | printd(", bad fcmod"); |
| 203 | } |
| 204 | } |
| 205 | } else if (SEQ_LEQ(segnum, np->na_xmtoth)) |
| 206 | np->n_flags |= NF_OTHACK; |
| 207 | break; |
| 208 | |
| 209 | case NSPLS_INTREQ: |
| 210 | if (seqnum == SEQ_ADD(np->na_xmtoth, 1)) { |
| 211 | if (fcval >= 0 && np->nf_remint+fcval <= 127) { |
| 212 | np->nf_remint += fcval; |
| 213 | np->na_xmtoth = segnum; |
| 214 | np->n_flags |= NF_OTHACK; |
| 215 | } else if (SEQ_LEQ(segnum, np->na_xmtoth)) |
| 216 | np->n_flags |= NF_OTHACK; |
| 217 | break; |
| 218 | |
| 219 | default: |
| 220 | printd(", bad fcvalint"); |
| 221 | } |
| 222 | break; |
| 223 | |
| 224 | /* |
| 225 | * Got an acknowledgement for a Data message. |
| 226 | * Nsp_chkaddr processes the ack, nothing else |
| 227 | * to do. |
| 228 | */ |
| 229 | case NSP_DATACK: |
| 230 | printd(", DATACK"); |
| 231 | np = nsp_chkaddr(m, srcnode, NSP_DATACK, &segnum); |
| 232 | if (np == 0) { |
| 233 | m_freem(m); |
| 234 | goto next; |
| 235 | } |
| 236 | break; |
| 237 | |
| 238 | /* |
| 239 | * Got an acknowledgement for an Other Data message. |
| 240 | * Nsp_chkaddr processes the ack, nothing else to do. |
| 241 | */ |
| 242 | case NSP_OTHACK: |
| 243 | printd(", OTHACK"); |
| 244 | np = nsp_chkaddr(m, srcnode, NSP_OTHACK, &segnum); |
| 245 | if (np == 0) { |
| 246 | m_freem(m); |
| 247 | goto next; |
| 248 | } |
| 249 | break; |
| 250 | |
| 251 | /* |
| 252 | * Got a Connect Acknowledgement. Just verify |
| 253 | * the address and perform the state transition. |
| 254 | */ |
| 255 | case NSP_CONACK: |
| 256 | DOIT |
| 257 | break; |
| 258 | |
| 259 | /* |
| 260 | * Got an unknown message, count it and flush it. |
| 261 | */ |
| 262 | default: |
| 263 | printd(", UNKNOWN!!!"); |
| 264 | m_freem(m); |
| 265 | break; |
| 266 | } |
| 267 | printd("\n"); |
| 268 | goto next; |
| 269 | } |