src/dps8/fnpuv.c

/* */
This source file includes following definitions.
tun_alloc
alloc_buffer
fnpuv_associated_brk
fnpuv_associated_readcb
fnpuv_3270_readcb
fnpuv_unassociated_readcb
fuv_close_cb
close_connection
fuv_read_cb
fuv_write_cb
fuv_write_3270_cb
fnpuv_start_write_3270_actual
fnpuv_start_write_actual
fnpuv_start_write
fnpuv_start_3270_write
fnpuv_start_writestr
fnpuv_send_eor
fnpuv_recv_eor
fnpuv_read_start
fnpuv_read_stop
on_new_connection
fnpuvInit
fnpuvProcessEvent
on_dialout_connect
fnpuv_dial_out
fnpuv_open_slave
processPacketInput
fnoTUNProcessLine
fnpTUNProcessEvent
fnpuv3270Poll
on_new_3270_connection
fnpuv3270Init
   1 /*
   2  * vim: filetype=c:tabstop=4:ai:expandtab
   3  * SPDX-License-Identifier: ICU
   4  * scspell-id: 2fdee814-f62f-11ec-8f3d-80ee73e9b8e7
   5  *
   6  * ---------------------------------------------------------------------------
   7  *
   8  * Copyright (c) 2016 Charles Anthony
   9  * Copyright (c) 2016 Michal Tomek
  10  * Copyright (c) 2021-2022 The DPS8M Development Team
  11  *
  12  * All rights reserved.
  13  *
  14  * This software is made available under the terms of the ICU
  15  * License, version 1.8.1 or later.  For more details, see the
  16  * LICENSE.md file at the top-level directory of this distribution.
  17  *
  18  * ---------------------------------------------------------------------------
  19  */
  20 
  21 // The FNP <--> libuv interface
  22 //
  23 // Every libuv TCP connection has a uv_tcp_t object.
  24 //
  25 // The uv_tcp_t object has a 'user data' field defined as "void * data".
  26 //
  27 // This code stores a pointer to a "struct uvClientData" in 'data'; this
  28 // structure allows this code to determine which HSLA line the connection
  29 // has been made with.
  30 //
  31 // The uvClientData structure contains:
  32 //
  33 //    bool assoc
  34 //    uint fnpno;
  35 //    uint lineno;
  36 //
  37 //       If 'assoc' is true, the TCP connection is associated with a particular
  38 //       HSLA line as specified by 'fnpno' and 'lineno'. A dialup line is
  39 //       associated by the user entering the FNP name and line number in the
  40 //       multiplexor dial in dialog. For slave and dialout lines, 'assoc'
  41 //       is always true as the association is predetermined by the FNP
  42 //       configuration.
  43 //
  44 //    char buffer [1024];
  45 //    size_t nPos;
  46 //
  47 //      Line canonicalization buffer used by the multiplexor dial in dialog.
  48 //
  49 // Each HSLA line is identified by a 'fnpno', 'lineno' pair. 'fnpno' indexes
  50 // into the 'fnpUnitData' data structure and 'lineno' into
  51 // 'fnpUnitData[fnpno].MState.line[]'.
  52 //
  53 // The 'line' structure contains:
  54 //
  55 //   enum service_types service;
  56 //
  57 //     This tracks the Multics' line configuration of 'dialup', 'dialout', and
  58 //     'slave'.
  59 //
  60 //   uv_tcp_t * client;
  61 //
  62 //     If this is non-null, the HSLA has a TCP connection.
  63 //
  64 //   telnet_t * telnetp;
  65 //
  66 //     If this is non-null, Telnet is enabled on the connection.
  67 //
  68 //   uv_tcp_t server;
  69 //
  70 //     This is used by the 'slave' logic and holds the handle of the
  71 //     TCP server port for the slave line.
  72 //
  73 //     The data field of 'server' points to a uvClientData structure; this
  74 //     field is used by the incoming connection handler to distinguish the
  75 //     slave and dialup server ports. (If null, dialup; else slave.)
  76 //
  77 //   uv_connect_t doConnect;
  78 //
  79 //     libuv uses a uv_connect_t object to create outbound connections;
  80 //     the dialout code uses 'doConnect' for this.
  81 //
  82 //   int port;
  83 //
  84 //     The port number that a slave line listens on.
  85 //
  86 
  87 // Dialup logic.
  88 //
  89 // The code assumes a single port number for all dialup lines, even for the
  90 // case of multiple FNPs.
  91 //
  92 // 'fnpuvInit()' is called when by the 'fnpserverport' command logic. It
  93 // creates a TCP server listen port, assigning 'on_new_connection()' as
  94 // the connection callback handler.
  95 //
  96 // When a connection is made to the listen port, libuv invokes the
  97 // 'on_new_connection()' callback handler.
  98 //
  99 // The handler creates a 'uv_tcp_t' object 'client' and accepts the
 100 // connection.
 101 //
 102 // It then checks the 'data' field on the listener object to see if this
 103 // is a dialup or slave listener. For the case of dialup, a 'uvClientData'
 104 // object is created and its 'assoc' field is set to false to flag the
 105 // the connection as not yet being associated with an HSLA line; the
 106 // libtelnet data structure is initialized and the initial Telnet negotiations
 107 // are started. 'client->data' is set to the 'uvClientData' object,
 108 // reading is enabled on 'client', and the HSLA line selection dialog
 109 // prompt is sent down the dialup connection.
 110 //
 111 // When input data is ready on the connection (user input), libuv allocates
 112 // a buffer, fills it with the data calls the 'fuv_read_cb()' callback handler.
 113 //
 114 // The handler looks at the 'data' field of the connection to access the
 115 // 'uvClientData' structure; if the structure indicates that Telnet
 116 // processing is to be done, it passes the data to libtelent handler.
 117 // Otherwise, it checks the 'assoc' field; if true the data is passed to the
 118 // FNP incoming data handler; if false, to the multiplexor line selection
 119 // dialog handler. The libtelnet handler, after stripping and processing
 120 // Telnet overhead passes any remaining data on in the same manner.
 121 // The data buffer is then freed, and the callback returns.
 122 //
 123 // Since the FNP incoming data handler is dependent on Multics accepting
 124 // the input data before it can safely dispose of the data, it disables
 125 // reading on the connection, and reenables it when Multics has accepted the
 126 // data.
 127 
 128 // Data are written to the TCP connections with 'fnpuv_start_write()'. The
 129 // 'uvClientData' is inspected for telnet usage; if so, the data is passed
 130 // to libtelnet for telnet packaging and is sent on to
 131 // 'fnpuv_start_write_actual'. If telnet is not in play, the data is sent
 132 // directly on to 'fnpuv_start_write_actual()' There, a buffer is allocated
 133 // and the data copied and a 'uv_write_t' request object is created and
 134 // initialized data the buffer address and length, and a write request
 135 // is send to libuv.
 136 //
 137 // When the write is complete, libuv calls the write callback 'fuv_write_cb()',
 138 // which frees the data buffers and destroys the write request object.
 139 
 140 // Dialout logic
 141 //
 142 // When the FNP receives a 'dial_out' command, it calls 'fnpuv_dial_out()'.
 143 // The dial string is parsed for IP address, port number and telnet flag.
 144 // An 'uv_tcp_t' object constructed and its address stored in the HSLA
 145 // 'client' field. An 'uvClientData' object is created, associated with
 146 // the dialout line HSLA, and if the Telnet flag is set, the Telnet processor
 147 // is initialized. The TCP connect is initiated and the procedure returns.
 148 //
 149 // When the connection succeeds or times out, the 'on_dialout_connect()' callback
 150 // is called. on_dialout_connect retrieves the 'uvClientData'. If the connection
 151 // succeeded, the connection data field is set to the 'uvClientData'; read is
 152 // enabled on the connection, and the 'accept_new_terminal' flag is set which
 153 // will cause an 'accept_new_terminal' command to be send to Multics.
 154 //
 155 
 156 #ifdef TUN
 157 // TUN interface
 158 
 159 // If makes more sense to me to have the emulator on an endpoint, but
 160 // that's not really the way ethernet works; for the nonce, we will
 161 // create a subnet and route to it with a tun device; the emulator
 162 // will listen on the device and do the whole ARP rigamorole.
 163 //
 164 // It's not clear to me what happens if multiple emulators are listening
 165 // on the same tun device, do they each get a copy of the message (i.e.
 166 // are we wired as point-to-point)?
 167 //
 168 // Create device node:
 169 //   mkdir /dev/net (if it doesn't exist already)
 170 //   mknod /dev/net/tun c 10 200
 171 //   chmod 0666 /dev/net/tun
 172 //   modprobe tun
 173 //
 174 // The subnet gateway device is 'dps8m' at address 192.168.8.0
 175 //
 176 //   sudo ip tuntap add mode tun dps8m
 177 //   sudo ip link set dps8m up
 178 //   sudo ip addr add 192.168.8.1/24 dev dps8m
 179 #endif
 180 
 181 #define ASSUME0 0
 182 
 183 #include <stdio.h>
 184 #include <stdlib.h>
 185 #include <unistd.h>
 186 #include <ctype.h>
 187 #include <signal.h>
 188 #ifdef TUN
 189 # include <string.h>
 190 # include <fcntl.h>
 191 # include <errno.h>
 192 # include <sys/ioctl.h>
 193 # include <sys/types.h>
 194 # include <sys/stat.h>
 195 # include <netinet/in.h>
 196 # include <sys/socket.h>
 197 # include <linux/if.h>
 198 # include <linux/if_tun.h>
 199 #endif
 200 
 201 #include "dps8.h"
 202 #include "dps8_scu.h"
 203 #include "dps8_sys.h"
 204 #include "dps8_iom.h"
 205 #include "dps8_cable.h"
 206 #include "dps8_cpu.h"
 207 #include "dps8_fnp2.h"
 208 #include "dps8_utils.h"
 209 #include "fnpuv.h"
 210 #include "fnptelnet.h"
 211 
 212 #ifdef TESTING
 213 # undef realloc
 214 # undef FREE
 215 # define FREE(p) free(p)
 216 # define realloc trealloc
 217 #endif /* ifdef TESTING */
 218 
 219 #define USE_REQ_DATA
 220 
 221 // Making it up...
 222 #define DEFAULT_BACKLOG 1024
 223 
 224 #ifdef TUN
 225 static int tun_alloc (char * dev)
     /*  */
 226   {
 227     struct ifreq ifr;
 228     int fd, err;
 229 
 230     if ((fd = open ("/dev/net/tun", O_RDWR)) < 0)
 231       //return tun_alloc_old (dev);
 232       return fd;
 233 
 234     memset (& ifr, 0,  sizeof (ifr));
 235 
 236     /*
 237      *  Flags: IFF_TUN   - TUN device (no Ethernet headers)
 238      *        IFF_TAP   - TAP device
 239      *
 240      *        IFF_NO_PI - Do not provide packet information
 241      */
 242 
 243     ifr.ifr_flags = IFF_TUN;
 244     if (* dev)
 245       strncpy (ifr.ifr_name, dev, IFNAMSIZ);
 246 
 247     if ((err = ioctl (fd, TUNSETIFF, (void *) & ifr)) < 0)
 248       {
 249         close (fd);
 250         return err;
 251       }
 252     strcpy (dev, ifr.ifr_name);
 253     return fd;
 254   }
 255 #endif
 256 
 257 //
 258 // alloc_buffer: libuv callback handler to allocate buffers for incoming data.
 259 //
 260 
 261 static void alloc_buffer (UNUSED uv_handle_t * handle, size_t suggested_size,
     /*  */
 262                           uv_buf_t * buf)
 263  {
 264 /* Suppress Clang Analyzer's possible memory leak warning */
 265 #if !defined ( __clang_analyzer__ )
 266     * buf = uv_buf_init ((char *) malloc (suggested_size), (uint) suggested_size);
 267 #endif /* if !defined ( __clang_analyzer__ ) */
 268   }
 269 
 270 void fnpuv_associated_brk (uv_tcp_t * client)
     /*  */
 271   {
 272     if (! client || uv_is_closing ((uv_handle_t *) client))
 273       return;
 274     if (! client->data)
 275       {
 276         sim_warn ("fnpuv_associated_brk bad client data\r\n");
 277         return;
 278       }
 279     uvClientData * p = (uvClientData *) client->data;
 280     uint fnpno = p -> fnpno;
 281     uint lineno = p -> lineno;
 282     struct t_line * linep = & fnpData.fnpUnitData[fnpno].MState.line[lineno];
 283     // The break key forces an input buffer flush.
 284     // XXX is this a race condition? Is it possible for processFnpMbx to see
 285     // the line_break before the accept input?
 286     linep->accept_input = 1;
 287     linep->line_break=true;
 288   }
 289 
 290 // read callback for connections that are associated with an HSLA line;
 291 // forward the data to the FNP input handler
 292 
 293 void fnpuv_associated_readcb (uv_tcp_t * client,
     /*  */
 294                            ssize_t nread,
 295                            unsigned char * buf)
 296   {
 297     processLineInput (client, buf, nread);
 298   }
 299 
 300 void fnpuv_3270_readcb (uv_tcp_t * client,
     /*  */
 301                            ssize_t nread,
 302                            unsigned char * buf)
 303   {
 304     process3270Input (client, buf, nread);
 305   }
 306 
 307 // read callback for connections that are no associated with an HSLA line;
 308 // forward the data to the line selection dialog handler
 309 
 310 void fnpuv_unassociated_readcb (uv_tcp_t * client,
     /*  */
 311                            ssize_t nread,
 312                            unsigned char * buf)
 313   {
 314     //printf ("unassoc. <%*s>\n", (int) nread, buf->base);
 315     processUserInput (client, buf, nread);
 316   }
 317 
 318 static void fuv_close_cb (uv_handle_t * stream)
     /*  */
 319   {
 320     FREE (stream);
 321   }
 322 
 323 // teardown a connection
 324 
 325 void close_connection (uv_stream_t* stream)
     /*  */
 326   {
 327     if (! stream)
 328       {
 329         sim_warn ("close_connection bad client data\r\n");
 330         return;
 331       }
 332     uvClientData * p = (uvClientData *) stream->data;
 333 
 334     // If stream->data, the stream is associated with a Multics line.
 335     // Tear down that association
 336     //if (p && fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno].service != service_3270)
 337     if (p)
 338       {
 339         // If assoc is false, then the disconnect happened before the actual
 340         // association took place
 341         if (p->assoc)
 342           {
 343             struct t_line * linep = & fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno];
 344             if (linep->service  == service_3270)
 345              {
 346                // On the 3270, the station closing does not close the controller
 347                sim_printf ("\r[FNP emulation: TN3270 %d.%d DISCONNECT]\r\n", ASSUME0, p->stationNo);
 348              }
 349             else
 350               {
 351                 sim_printf ("\r[FNP emulation: DISCONNECT %c.d%03d]\r\n", p->fnpno+'a', p->lineno);
 352 #ifdef DISC_DELAY
 353                 linep -> line_disconnected = DISC_DELAY;
 354 #else
 355                 linep -> line_disconnected = true;
 356 #endif
 357                 linep -> listen = false;
 358                 if (linep->inBuffer)
 359                   FREE (linep->inBuffer);
 360                 linep->inBuffer = NULL;
 361                 linep->inSize   = 0;
 362                 linep->inUsed   = 0;
 363                 linep->nPos     = 0;
 364               }
 365             if (linep->line_client)
 366               {
 367                 // linep->line_client is a copied stream->data; will be freed
 368                 // below
 369                 linep->line_client = NULL;
 370               }
 371           }
 372         else // ! p-assoc
 373           {
 374             sim_printf ("\r[FNP emulation: DISCONNECT]\r\n");
 375           }
 376         // Clean up allocated data
 377         if (p->telnetp)
 378           {
 379             telnet_free (p->telnetp);
 380             // telnet_free frees self
 381             //free (p->telnetp);
 382             p->telnetp = NULL;
 383           }
 384         if (((uvClientData *) stream->data)->ttype)
 385           FREE (((uvClientData *) stream->data)->ttype);
 386         FREE (stream->data);
 387         stream->data = NULL;
 388       } // if (p)
 389     if (! uv_is_closing ((uv_handle_t *) stream))
 390       uv_close ((uv_handle_t *) stream, fuv_close_cb);
 391   }
 392 
 393 //
 394 // fuv_read_cb: libuv read complete callback
 395 //
 396 //   Cleanup on read error.
 397 //   Forward data to appropriate handler.
 398 
 399 static void fuv_read_cb (uv_stream_t* stream,
     /*  */
 400                          ssize_t nread,
 401                          const uv_buf_t* buf)
 402   {
 403     if (nread < 0)
 404       {
 405         //if (nread == UV_EOF)
 406           {
 407             close_connection (stream);
 408           }
 409       }
 410     else if (nread > 0)
 411       {
 412         if (! stream)
 413           {
 414             sim_warn ("fuv_read_cb bad client data\r\n");
 415             return;
 416           }
 417         uvClientData * p = (uvClientData *) stream->data;
 418         if (p)
 419           {
 420             if (p->telnetp)
 421               {
 422                 telnet_recv (p->telnetp, buf->base, (size_t) nread);
 423               }
 424             else
 425               {
 426 
 427                 (* p->read_cb) ((uv_tcp_t *) stream, nread, (unsigned char *) buf->base);
 428 
 429 
 430 
 431 
 432 
 433 
 434 
 435 
 436 
 437 
 438 
 439               }
 440           }
 441       }
 442 
 443     if (buf->base)
 444         free (buf->base);
 445   }
 446 
 447 //
 448 // fuv_write_cb: libuv write complete callback
 449 //
 450 //   Cleanup on error
 451 //   Free buffers
 452 //
 453 
 454 static void fuv_write_cb (uv_write_t * req, int status)
     /*  */
 455   {
 456     if (status < 0)
 457       {
 458         if (status == -ECONNRESET || status == -ECANCELED ||
 459             status == -EPIPE)
 460           {
 461             // This occurs when the other end disconnects; not an "error"
 462           }
 463         else
 464           {
 465             sim_warn ("fuv_write_cb status %d (%s)\n", -status, strerror (-status));
 466           }
 467 
 468         // connection reset by peer
 469         close_connection (req->handle);
 470       }
 471 
 472 #ifdef USE_REQ_DATA
 473 //sim_printf ("freeing bufs %p\n", req->data);
 474     FREE (req->data);
 475 #else
 476     unsigned int nbufs = req->nbufs;
 477     uv_buf_t * bufs = req->bufs;
 478     //if (! bufs)
 479 
 480 
 481 
 482 
 483 //sim_printf ("fuv_write_cb req %p req->data %p bufs %p nbufs %u\n", req, req->data, bufs, nbufs);
 484     for (unsigned int i = 0; i < nbufs; i ++)
 485       {
 486         if (bufs && bufs[i].base)
 487           {
 488 //sim_printf ("freeing bufs%d %p\n", i, bufs[i].base);
 489             FREE (bufs[i].base);
 490             //bufp -> base = NULL;
 491           }
 492         if (req->bufsml[i].base)
 493           {
 494 //sim_printf ("freeing bufsml%d %p@%p\n", i, req->bufsml[i].base, & req->bufsml[i].base);
 495             FREE (req->bufsml[i].base);
 496           }
 497       }
 498 #endif
 499 
 500     // the buf structure is copied; do not free.
 501 //sim_printf ("freeing req %p\n", req);
 502     FREE (req);
 503   }
 504 
 505 //
 506 // fuv_write_3270_cb: libuv write complete callback
 507 //
 508 //   Cleanup on error
 509 //   Free buffers
 510 //
 511 
 512 static void fuv_write_3270_cb (uv_write_t * req, int status) {
     /*  */
 513     uv_tcp_t * client = (uv_tcp_t *) req->handle;
 514     fuv_write_cb (req, status);
 515     set_3270_write_complete (client);
 516   }
 517 
 518 // Create and start a write request
 519 
 520 static void fnpuv_start_write_3270_actual (UNUSED uv_tcp_t * client, unsigned char * data, ssize_t datalen)
     /*  */
 521   {
 522 #ifdef TESTING
 523 sim_printf ("fnpuv_start_write_3270_actual\r\n");
 524 #endif
 525 
 526 
 527 
 528 
 529 
 530 
 531 
 532 
 533 
 534 
 535 
 536 
 537 
 538 
 539 
 540 
 541 
 542 
 543 
 544 
 545 
 546 
 547 
 548     // Find the client from the device selection call
 549 
 550     uint stn_no;
 551     for (stn_no = 0; stn_no < ADDR_MAP_ENTRIES; stn_no ++)
 552       if (addr_map [stn_no] == fnpData.ibm3270ctlr[ASSUME0].selDevChar)
 553         break;
 554     if (stn_no >= ADDR_MAP_ENTRIES)
 555       {
 556         sim_printf ("fnpuv_start_write_3270_actual couldn't find selDevChar %02x\r\n", (unsigned int) fnpData.ibm3270ctlr[ASSUME0].selDevChar);
 557         return;
 558       }
 559     uv_tcp_t * stn_client = fnpData.ibm3270ctlr[ASSUME0].stations[stn_no].client;
 560     if (! stn_client || uv_is_closing ((uv_handle_t *) stn_client))
 561       return;
 562 
 563     // Allocate write request
 564 /* Suppress Clang Analyzer's possible memory leak warning */
 565 #if !defined ( __clang_analyzer__ )
 566     uv_write_t * req = (uv_write_t *) malloc (sizeof (uv_write_t));
 567     if (!req)
 568       {
 569         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
 570                  __func__, __FILE__, __LINE__);
 571 # if defined(USE_BACKTRACE)
 572 #  ifdef SIGUSR2
 573         (void)raise(SIGUSR2);
 574         /*NOTREACHED*/ /* unreachable */
 575 #  endif /* ifdef SIGUSR2 */
 576 # endif /* if defined(USE_BACKTRACE) */
 577         abort();
 578       }
 579     // This makes sure that bufs*.base and bufsml*.base are NULL
 580     memset (req, 0, sizeof (uv_write_t));
 581     uv_buf_t buf = uv_buf_init ((char *) malloc ((unsigned long) datalen), (uint) datalen);
 582 //sim_printf ("allocated req %p data %p\n", req, buf.base);
 583 # ifdef USE_REQ_DATA
 584     req->data = buf.base;
 585 # endif
 586 //sim_printf ("fnpuv_start_write_actual req %p buf.base %p\n", req, buf.base);
 587     memcpy (buf.base, data, (unsigned long) datalen);
 588     int ret = uv_write (req, (uv_stream_t *) stn_client, & buf, 1, fuv_write_3270_cb);
 589 // There seems to be a race condition when Multics signals a disconnect_line;
 590 // We close the socket, but Multics is still writing its goodbye text trailing
 591 // NULs.
 592 // If the socket has been closed, write will return BADF; just ignore it.
 593     if (ret < 0 && ret != -EBADF)
 594       sim_printf ("\r[FNP emulation: uv_write returned %d]\r\n", ret);
 595 #endif /* if !defined ( __clang_analyzer__ ) */
 596   }
 597 
 598 void fnpuv_start_write_actual (uv_tcp_t * client, unsigned char * data, ssize_t datalen)
     /*  */
 599   {
 600     if (! client || uv_is_closing ((uv_handle_t *) client))
 601       return;
 602 /* Suppress Clang Analyzer's possible memory leak warning */
 603 #if !defined ( __clang_analyzer__ )
 604     uv_write_t * req = (uv_write_t *) malloc (sizeof (uv_write_t));
 605     if (!req)
 606       {
 607         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
 608                  __func__, __FILE__, __LINE__);
 609 # if defined(USE_BACKTRACE)
 610 #  ifdef SIGUSR2
 611         (void)raise(SIGUSR2);
 612         /*NOTREACHED*/ /* unreachable */
 613 #  endif /* ifdef SIGUSR2 */
 614 # endif /* if defined(USE_BACKTRACE) */
 615         abort();
 616       }
 617     // This makes sure that bufs*.base and bufsml*.base are NULL
 618     memset (req, 0, sizeof (uv_write_t));
 619     uv_buf_t buf = uv_buf_init ((char *) malloc ((unsigned long) datalen), (uint) datalen);
 620 //sim_printf ("allocated req %p data %p\n", req, buf.base);
 621 # ifdef USE_REQ_DATA
 622     req->data = buf.base;
 623 # endif
 624 //sim_printf ("fnpuv_start_write_actual req %p buf.base %p\n", req, buf.base);
 625     memcpy (buf.base, data, (unsigned long) datalen);
 626     int ret = uv_write (req, (uv_stream_t *) client, & buf, 1, fuv_write_cb);
 627 // There seems to be a race condition when Multics signals a disconnect_line;
 628 // We close the socket, but Multics is still writing its goodbye text trailing
 629 // NULs.
 630 // If the socket has been closed, write will return BADF; just ignore it.
 631     if (ret < 0 && ret != -EBADF)
 632       sim_printf ("\r[FNP emulation: uv_write returned %d]\r\n", ret);
 633 #endif /* if !defined ( __clang_analyzer__ ) */
 634   }
 635 
 636 //
 637 // Write data to a connection, doing Telnet if needed.
 638 //
 639 
 640 void fnpuv_start_write (uv_tcp_t * client, unsigned char * data, ssize_t datalen)
     /*  */
 641   {
 642     if (! client || uv_is_closing ((uv_handle_t *) client))
 643       return;
 644     uvClientData * p = (uvClientData *) client->data;
 645     if (! p) //-V547
 646       return;
 647     if (!p->telnetp)
 648       {
 649         sim_warn ("telnetp NULL; dropping fnpuv_start_write()\n");
 650         return;
 651       }
 652     telnet_send (p->telnetp, (char *) data, (size_t) datalen);
 653   }
 654 
 655 void fnpuv_start_3270_write (uv_tcp_t * client, unsigned char * data, ssize_t datalen)
     /*  */
 656   {
 657     if (! client || uv_is_closing ((uv_handle_t *) client) || ! client->data)
 658       return;
 659     uvClientData * p = (uvClientData *) client->data;
 660     if (! p) //-V547
 661       return;
 662 #ifdef TESTING
 663 sim_printf ("fnpuv_start_3270_write\r\n");
 664 #endif
 665 
 666 
 667 
 668 
 669 
 670 
 671 
 672 
 673 
 674 
 675 
 676 
 677 
 678 
 679 
 680 
 681 
 682 
 683 
 684 
 685 
 686 
 687 
 688     // Strip BSC protocol:
 689     //    STX <text> ETX
 690     //    EOT
 691 
 692     if (datalen == 1 && data [0] == 0x37) // EOT
 693       {
 694 #ifdef TESTING
 695 sim_printf ("fnpuv: detected EOT\r\n");
 696 #endif
 697         fnpuv_send_eor (client);
 698         return;
 699       }
 700 
 701     unsigned char * actual_data_start = data;
 702     unsigned long actual_datalen = (unsigned long) datalen;
 703     //bool send_eor = false;
 704     if (data [datalen - 1] == 0x03) // ETX
 705       {
 706         actual_datalen --;
 707         //send_eor = true;
 708       }
 709     if (data [0] == 0x02) // STX
 710       {
 711         actual_data_start ++;
 712         actual_datalen --;
 713         if (data [1] == 0x27) // ESC
 714           {
 715             actual_data_start ++;
 716             actual_datalen --;
 717           }
 718       }
 719 
 720     telnet_send (p->telnetp, (char *) actual_data_start, (size_t) actual_datalen);
 721     //if (send_eor)
 722       //fnpuv_send_eor (client);
 723   }
 724 
 725 // C-string wrapper for fnpuv_start_write
 726 
 727 void fnpuv_start_writestr (uv_tcp_t * client, unsigned char * data)
     /*  */
 728   {
 729     //fnpuv_start_write (client, data, (ssize_t) strlen (data));
 730     if (! client || uv_is_closing ((uv_handle_t *) client))
 731       return;
 732     if (! client->data)
 733       {
 734         sim_warn ("fnpuv_start_writestr bad client data\r\n");
 735         return;
 736       }
 737     uvClientData * p = client->data;
 738     (* p->write_cb) (client, data, (ssize_t) strlen ((char *) data));
 739   }
 740 
 741 void fnpuv_send_eor (uv_tcp_t * client)
     /*  */
 742   {
 743     if (! client || uv_is_closing ((uv_handle_t *) client))
 744       return;
 745     if (! client->data)
 746       {
 747         sim_warn ("fnpuv_send_eor bad client data\r\n");
 748         return;
 749       }
 750     uvClientData * p = (uvClientData *) client->data;
 751     ltnEOR (p->telnetp);
 752     //unsigned char EOR [] = { TELNET_IAC, TELNET_EOR };
 753     //fnpuv_start_write_special (client, (char *) EOR, sizeof (EOR));
 754   }
 755 
 756 void fnpuv_recv_eor (uv_tcp_t * client)
     /*  */
 757   {
 758     fnpRecvEOR (client);
 759   }
 760 
 761 //
 762 // Enable reading on connection
 763 //
 764 
 765 void fnpuv_read_start (uv_tcp_t * client)
     /*  */
 766   {
 767     if (! client || uv_is_closing ((uv_handle_t *) client))
 768       return;
 769     uv_read_start ((uv_stream_t *) client, alloc_buffer, fuv_read_cb);
 770   }
 771 
 772 //
 773 // Disable reading on connection
 774 //
 775 
 776 void fnpuv_read_stop (uv_tcp_t * client)
     /*  */
 777   {
 778     if (! client || uv_is_closing ((uv_handle_t *) client))
 779       return;
 780     uv_read_stop ((uv_stream_t *) client);
 781   }
 782 
 783 //
 784 // Connection callback handler for dialup connections
 785 //
 786 
 787 static void on_new_connection (uv_stream_t * server, int status)
     /*  */
 788   {
 789     if (status < 0)
 790       {
 791         sim_printf ("\r[FNP emulation: new connection error: %s]\r\n", uv_strerror (status));
 792         // error!
 793         return;
 794       }
 795 
 796     uv_tcp_t * client = (uv_tcp_t *) malloc (sizeof (uv_tcp_t));
 797     if (!client)
 798       {
 799         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
 800                  __func__, __FILE__, __LINE__);
 801 #if defined(USE_BACKTRACE)
 802 # ifdef SIGUSR2
 803         (void)raise(SIGUSR2);
 804         /*NOTREACHED*/ /* unreachable */
 805 # endif /* ifdef SIGUSR2 */
 806 #endif /* if defined(USE_BACKTRACE) */
 807         abort();
 808       }
 809     uv_tcp_init (fnpData.loop, client);
 810     if (uv_accept (server, (uv_stream_t *) client) != 0)
 811       {
 812         uv_close ((uv_handle_t *) client, fuv_close_cb);
 813         return;
 814       }
 815 
 816     // if server->data is non-null, this is a slave server; else a dialup
 817     // server
 818     if (server->data)
 819       {
 820         uvClientData * p = (uvClientData *) server->data;
 821         struct t_line * linep = & fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno];
 822 
 823         // Slave servers only handle a single connection at a time
 824         if (linep->line_client)
 825           {
 826             uv_close ((uv_handle_t *) client, fuv_close_cb);
 827 # ifdef TESTING
 828 sim_printf ("\r[FNP emulation: dropping 2nd slave]\r\n");
 829 # endif
 830             return;
 831           }
 832 
 833         linep->line_client = client;
 834       }
 835 
 836     struct sockaddr name;
 837     int namelen = sizeof (name);
 838     uv_tcp_nodelay (client,1);
 839     int ret = uv_tcp_getpeername (client, & name, & namelen);
 840     if (ret < 0)
 841       {
 842         sim_printf ("\r[FNP emulation: CONNECT; addr err %d]\r\n", ret);
 843       }
 844     else
 845       {
 846         struct sockaddr_in * p = (struct sockaddr_in *) & name;
 847         sim_printf ("\r[FNP emulation: CONNECT %s]\r\n", inet_ntoa (p -> sin_addr));
 848       }
 849 
 850     uvClientData * p = (uvClientData *) malloc (sizeof (uvClientData));
 851     if (! p)
 852       {
 853          fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
 854                   __func__, __FILE__, __LINE__);
 855 #if defined(USE_BACKTRACE)
 856 # ifdef SIGUSR2
 857         (void)raise(SIGUSR2);
 858         /*NOTREACHED*/ /* unreachable */
 859 # endif /* ifdef SIGUSR2 */
 860 #endif /* if defined(USE_BACKTRACE) */
 861         abort();
 862       }
 863     client->data       = p;
 864     p->assoc           = false;
 865     p->nPos            = 0;
 866     p->ttype           = NULL;
 867     p->write_actual_cb = fnpuv_start_write_actual;
 868     // dialup connections are routed through libtelent
 869     if (! server->data)
 870       {
 871         p->read_cb  = fnpuv_unassociated_readcb;
 872         p->write_cb = fnpuv_start_write;
 873         p->telnetp  = ltnConnect (client);
 874 
 875         if (! p->telnetp)
 876           {
 877              sim_warn ("ltnConnect failed\n");
 878              return;
 879           }
 880       }
 881     else
 882       {
 883         p->read_cb       = fnpuv_associated_readcb;
 884         p->write_cb      = fnpuv_start_write_actual;
 885         p->telnetp       = NULL;
 886         uvClientData * q = (uvClientData *) server->data;
 887         p->fnpno         = q->fnpno;
 888         p->lineno        = q->lineno;
 889         p->assoc         = true;
 890       }
 891     fnpuv_read_start (client);
 892     if (! server->data)
 893       fnpConnectPrompt (client);
 894     else
 895       {
 896         uvClientData * p = (uvClientData *) server->data;
 897         struct t_line * linep = & fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno];
 898         if (linep->lineType == 0) /* LINE_NONE */
 899           linep->lineType = 1; /* LINE_ASCII */
 900         linep->accept_new_terminal = true;
 901         reset_line (linep);
 902       }
 903   }
 904 
 905 //
 906 // Setup the dialup listener
 907 //
 908 
 909 int fnpuvInit (int telnet_port, char * telnet_address)
     /*  */
 910   {
 911     // Ignore multiple calls; this means that once the listen port is
 912     // opened, it can't be changed. Fixing this requires non-trivial
 913     // changes.
 914     if (fnpData.du_server_inited)
 915       {
 916         sim_printf ("\r[FNP emulation: FNP already initialized]\r\n");
 917         return 1;
 918       }
 919 
 920     if (! fnpData.loop)
 921       fnpData.loop = uv_default_loop ();
 922 
 923     // Initialize the server socket
 924     fnpData.loop = uv_default_loop ();
 925     uv_tcp_init (fnpData.loop, & fnpData.du_server);
 926 
 927 // XXX to do clean shutdown
 928 // uv_loop_close (fnpData.loop);
 929 
 930     // Flag the this server as being the dialup server
 931     fnpData.du_server.data = NULL;
 932 
 933     // Bind and listen
 934     struct sockaddr_in addr;
 935     uv_ip4_addr (telnet_address, telnet_port, & addr);
 936     uv_tcp_bind (& fnpData.du_server, (const struct sockaddr *) & addr, 0);
 937     int r = uv_listen ((uv_stream_t *) & fnpData.du_server, DEFAULT_BACKLOG,
 938                        on_new_connection);
 939     if (r)
 940      {
 941         sim_printf ("\r[FNP emulation: listen error: %s:%ld: %s]\r\n", telnet_address, (long) telnet_port, uv_strerror (r));
 942         return 1;
 943      }
 944     fnpData.du_server_inited = true;
 945     sim_printf ("\r[FNP emulation: TELNET server listening on %s:%ld]\r\n", telnet_address, (long) telnet_port);
 946     return 0;
 947   }
 948 
 949 // Make a single pass through the libuv event queue.
 950 
 951 void fnpuvProcessEvent (void)
     /*  */
 952   {
 953     // UV_RUN_NOWAIT: Poll for i/o once but don’t block if there are no
 954     // pending callbacks. Returns zero if done (no active handles or
 955     // requests left), or non-zero if more callbacks are expected (meaning
 956     // you should run the event loop again sometime in the future).
 957 
 958     // Note that uv_run returns non-zero if that are any active_handles
 959     // (e.g. TCP connection listener open); that means a non-zero
 960     // return does not mean i/o is pending.
 961     if (! fnpData.loop)
 962       return;
 963     /* int ret = */ uv_run (fnpData.loop, UV_RUN_NOWAIT);
 964   }
 965 
 966 //
 967 // dialout line connection callback
 968 //
 969 
 970 static void on_dialout_connect (uv_connect_t * server, int status)
     /*  */
 971   {
 972     sim_printf ("\r[FNP emulation: dialout connect]\r\n");
 973     uvClientData * p = (uvClientData *) server->handle->data;
 974     // If data is NULL, assume that the line has already been torn down.
 975     if (! p)
 976       {
 977          sim_printf ("\r[FNP emulation: NOTE: on_dialout_connect called with data == NULL]\r\n");
 978          return;
 979       }
 980     struct t_line * linep = & fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno];
 981     if (status < 0)
 982       {
 983         sim_printf ("\r[FNP emulation: dialout connection error: %s]\r\n", uv_strerror (status));
 984         //sim_printf ("%p\n", p);
 985         //sim_printf ("%d.%d\n", p->fnpno, p->lineno);
 986         linep->acu_dial_failure = true;
 987         return;
 988       }
 989 
 990     uv_read_start ((uv_stream_t *) linep->line_client, alloc_buffer, fuv_read_cb);
 991     linep->listen = true;
 992     if (linep->lineType == 0) /* LINE_NONE */
 993       linep->lineType = 1; /* LINE_ASCII */
 994     linep->accept_new_terminal = true;
 995     linep->was_CR              = false;
 996     linep->line_client->data   = p;
 997     if (p->telnetp)
 998       {
 999         ltnDialout (p->telnetp);
1000       }
1001   }
1002 
1003 //
1004 // Perform a dialout
1005 //
1006 
1007 void fnpuv_dial_out (uint fnpno, uint lineno, word36 d1, word36 d2, word36 d3)
     /*  */
1008   {
1009     if (! fnpData.loop)
1010       return;
1011     sim_printf ("\r[FNP emulation: received dial_out %c.h%03d %012llu %012llu %012llu]\r\n", fnpno+'a', lineno,
1012             (unsigned long long)d1, (unsigned long long)d2, (unsigned long long)d3);
1013     struct t_line * linep = & fnpData.fnpUnitData[fnpno].MState.line[lineno];
1014     uint d01   = (d1 >> 30) & 017;
1015     uint d02   = (d1 >> 24) & 017;
1016     uint d03   = (d1 >> 18) & 017;
1017     uint d04   = (d1 >> 12) & 017;
1018     uint d05   = (d1 >>  6) & 017;
1019     uint d06   = (d1 >>  0) & 017;
1020     uint d07   = (d2 >> 30) & 017;
1021     uint d08   = (d2 >> 24) & 017;
1022     uint d09   = (d2 >> 18) & 017;
1023     uint d10   = (d2 >> 12) & 017;
1024     uint d11   = (d2 >>  6) & 017;
1025     uint d12   = (d2 >>  0) & 017;
1026     uint flags = (d3 >> 30) & 017;
1027     uint p1    = (d3 >> 24) & 017;
1028     uint p2    = (d3 >> 18) & 017;
1029     uint p3    = (d3 >> 12) & 017;
1030     uint p4    = (d3 >>  6) & 017;
1031     uint p5    = (d3 >>  0) & 017;
1032 
1033     uint oct1  = d01 * 100 + d02 * 10 + d03;
1034     uint oct2  = d04 * 100 + d05 * 10 + d06;
1035     uint oct3  = d07 * 100 + d08 * 10 + d09;
1036     uint oct4  = d10 * 100 + d11 * 10 + d12;
1037 
1038     uint port  = ((((p1 * 10) + p2) * 10 + p3) * 10 + p4) * 10 + p5;
1039 
1040 // Flags
1041 //   1    Use Telnet
1042 #ifdef TUN
1043 //   2    Use TUN device (in which case 'port' is the netmask
1044 #endif
1045 //   4
1046 
1047 #ifdef TUN
1048     linep->is_tun = false;
1049     if (flags & 2)
1050       {
1051         if (linep->tun_fd <= 0)
1052           {
1053             char a_name [IFNAMSIZ] = "dps8m";
1054             linep->tun_fd = tun_alloc (a_name);
1055             if (linep->tun_fd < 0)
1056               {
1057                 sim_printf ("\r[FNP emulation: dialout TUN tun_alloc returned %d errno %d]\r\n", linep->tun_fd, errno);
1058                 return;
1059              }
1060             int flags = fcntl (linep->tun_fd, F_GETFL, 0);
1061             if (flags < 0)
1062               {
1063                 sim_printf ("\r[FNP emulation: dialout TUN F_GETFL returned < 0]\r\n");
1064                 return;
1065               }
1066             flags |= O_NONBLOCK;
1067             int ret = fcntl (linep->tun_fd, F_SETFL, flags);
1068             if (ret)
1069               {
1070                 sim_printf ("\r[FNP emulation: dialout TUN F_SETFL returned %d]\r\n", ret);
1071                 return;
1072               }
1073           }
1074           linep->is_tun = true;
1075           return;
1076         }
1077 #endif
1078 
1079 // firewall
1080 
1081     // Default is accept
1082     bool accept = true;
1083     uint32_t ip_addr = (uint32_t) ((oct1 << 24) | (oct2 << 16) | (oct3 << 8) | oct4);
1084     uint this_line = encodeline (fnpno, lineno);
1085     for (int i = 0; i < n_fw_entries; i ++)
1086       {
1087         struct fw_entry_s * p = fw_entries + i;
1088         if (this_line < p->line_0 || this_line > p->line_1)
1089           continue;
1090         if ((ip_addr & p->cidr_mask) != (p->ipaddr & p->cidr_mask))
1091           continue;
1092         accept = p->accept;
1093         break;
1094       }
1095 
1096     if (! accept)
1097       {
1098         sim_printf ("Dialout %c.d%03d denied\r\n", fnpno + 'a', lineno);
1099         linep->acu_dial_failure = true;
1100         return;
1101       }
1102 
1103     char ipaddr [256];
1104     sprintf (ipaddr, "%d.%d.%d.%d", oct1, oct2, oct3, oct4);
1105     sim_printf ("calling %s:%d\n", ipaddr,port);
1106 
1107     struct sockaddr_in dest;
1108     uv_ip4_addr(ipaddr, (int) port, &dest);
1109 
1110     linep->line_client = (uv_tcp_t *) malloc (sizeof (uv_tcp_t));
1111     if (!linep->line_client)
1112       {
1113         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1114                  __func__, __FILE__, __LINE__);
1115 #if defined(USE_BACKTRACE)
1116 # ifdef SIGUSR2
1117         (void)raise(SIGUSR2);
1118         /*NOTREACHED*/ /* unreachable */
1119 # endif /* ifdef SIGUSR2 */
1120 #endif /* if defined(USE_BACKTRACE) */
1121         abort();
1122       }
1123     uv_tcp_init (fnpData.loop, linep->line_client);
1124 
1125     uvClientData * p = (uvClientData *) malloc (sizeof (uvClientData));
1126     if (! p)
1127       {
1128         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1129                  __func__, __FILE__, __LINE__);
1130 #if defined(USE_BACKTRACE)
1131 # ifdef SIGUSR2
1132         (void)raise(SIGUSR2);
1133         /*NOTREACHED*/ /* unreachable */
1134 # endif /* ifdef SIGUSR2 */
1135 #endif /* if defined(USE_BACKTRACE) */
1136         abort();
1137       }
1138     p->assoc                 = true;
1139     p->read_cb               = fnpuv_associated_readcb;
1140     p->nPos                  = 0;
1141     p->ttype                 = NULL;
1142     p->fnpno                 = fnpno;
1143     p->lineno                = lineno;
1144     linep->line_client->data = p;
1145 
1146     if (flags & 1)
1147       {
1148         p->write_cb        = fnpuv_start_write;
1149         p->write_actual_cb = fnpuv_start_write_actual;
1150         p->telnetp         = ltnConnect (linep->line_client);
1151         if (! p->telnetp)
1152           {
1153               sim_warn ("ltnConnect failed\n");
1154           }
1155       }
1156     else
1157       {
1158         p->write_cb        = fnpuv_start_write_actual;
1159         p->write_actual_cb = fnpuv_start_write_actual;
1160         p->telnetp         = NULL; // Mark this line as 'not a telnet connection'
1161       }
1162 
1163     uv_tcp_connect (& linep->doConnect, linep->line_client, (const struct sockaddr *) & dest, on_dialout_connect);
1164   }
1165 
1166 
1167 
1168 
1169 
1170 
1171 
1172 
1173 
1174 
1175 
1176 
1177 
1178 
1179 
1180 
1181 
1182 
1183 
1184 //
1185 // Start a slave line connection listener.
1186 //
1187 
1188 void fnpuv_open_slave (uint fnpno, uint lineno)
     /*  */
1189   {
1190     if (! fnpData.loop)
1191       return;
1192     sim_printf ("\r[FNP emulation: fnpuv_open_slave %d.%d]\r\n", fnpno, lineno);
1193     struct t_line * linep = & fnpData.fnpUnitData[fnpno].MState.line[lineno];
1194 
1195     // Do we already have a listening port (ie not first time)?
1196     if (linep->server.data)
1197       return;
1198 
1199     uv_tcp_init (fnpData.loop, & linep->server);
1200 
1201     // Mark this server has being a slave server
1202     // XXX This does not get freed during a normal shutdown, as Multics
1203     // XXX doesn't tell idle slave lines anything. The emulator shutdown
1204     // XXX needs to call an FNP cleanup routine that frees this.
1205 
1206     uvClientData * p = (uvClientData *) malloc (sizeof (uvClientData));
1207     if (! p)
1208       {
1209         fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1210                  __func__, __FILE__, __LINE__);
1211 #if defined(USE_BACKTRACE)
1212 # ifdef SIGUSR2
1213         (void)raise(SIGUSR2);
1214         /*NOTREACHED*/ /* unreachable */
1215 # endif /* ifdef SIGUSR2 */
1216 #endif /* if defined(USE_BACKTRACE) */
1217         abort();
1218       }
1219     p->assoc           = false;
1220     p->read_cb         = fnpuv_associated_readcb;
1221     p->write_cb        = fnpuv_start_write_actual;
1222     p->write_actual_cb = fnpuv_start_write_actual;
1223     p->nPos            = 0;
1224     p->ttype           = NULL;
1225     p->fnpno           = fnpno;
1226     p->lineno          = lineno;
1227     linep->server.data = p;
1228     linep->line_client = NULL;
1229 
1230     struct sockaddr_in addr;
1231     uv_ip4_addr (fnpData.telnet_address, linep->port, & addr);
1232     uv_tcp_bind (& linep->server, (const struct sockaddr *) & addr, 0);
1233     int r = uv_listen ((uv_stream_t *) & linep->server, DEFAULT_BACKLOG,
1234                        on_new_connection);
1235     if (r)
1236      {
1237         sim_printf ("\r[FNP emulation: listen error: %s:%ld: %s]\r\n", fnpData.telnet_address, (long) linep->port, uv_strerror (r));
1238      }
1239     sim_printf ("\r[FNP emulation: listening on %s:%ld]\r\n", fnpData.telnet_address, (long) linep->port);
1240 
1241 // It should be possible to run a peer-to-peer TCP instead of client server,
1242 // but it's not clear to me how.
1243 
1244 
1245 
1246 
1247 
1248 
1249 
1250 
1251 
1252 
1253 
1254 
1255 
1256 
1257 
1258 
1259 
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1292   }
1293 
1294 #ifdef TUN
1295 static void processPacketInput (int fnpno, int lineno, unsigned char * buf, ssize_t nread)
     /*  */
1296   {
1297     //uvClientData * p = (uvClientData *) client->data;
1298     //uint fnpno       = p -> fnpno;
1299     //uint lineno      = p -> lineno;
1300     if (fnpno >= N_FNP_UNITS_MAX || lineno >= MAX_LINES)
1301       {
1302         sim_printf ("\r[FNP emulation: processPacketInput bogus client data]\r\n");
1303         return;
1304       }
1305 //sim_printf ("assoc. %d.%d nread %ld <%*s>\n", fnpno, lineno, (long) nread, buf);
1306 //{for (int i = 0; i < nread; i ++) sim_printf (" %03o", buf[i]);
1307  //sim_printf ("\n");
1308 //}
1309 
1310     struct t_line * linep = & fnpData.fnpUnitData[fnpno].MState.line[lineno];
1311     if (linep->inBuffer)
1312       {
1313         unsigned char * new = realloc (linep->inBuffer, (unsigned long) (linep->inSize + nread));
1314         if (! new)
1315           {
1316             fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1317                      __func__, __FILE__, __LINE__)
1318 # if defined(USE_BACKTRACE)
1319 #  ifdef SIGUSR2
1320             (void)raise(SIGUSR2);
1321             /*NOTREACHED*/ /* unreachable */
1322 #  endif /* ifdef SIGUSR2 */
1323 # endif /* if defined(USE_BACKTRACE) */
1324             abort();
1325           }
1326         memcpy (new + linep->inSize, buf, (unsigned long) nread);
1327         linep->inSize  += nread;
1328         linep->inBuffer = new;
1329       }
1330     else
1331       {
1332         linep->inBuffer = malloc ((unsigned long) nread);
1333         if (! linep->inBuffer)
1334           {
1335             fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1336                      __func__, __FILE__, __LINE__);
1337 # if defined(USE_BACKTRACE)
1338 #  ifdef SIGUSR2
1339             (void)raise(SIGUSR2);
1340             /*NOTREACHED*/ /* unreachable */
1341 #  endif /* ifdef SIGUSR2 */
1342 # endif /* if defined(USE_BACKTRACE) */
1343             abort();
1344           }
1345         memcpy (linep->inBuffer, buf, (unsigned long) nread);
1346         linep->inSize = (uint) nread;
1347         linep->inUsed = 0;
1348       }
1349 
1350   }
1351 
1352 static void fnoTUNProcessLine (int fnpno, int lineno, struct t_line * linep)
     /*  */
1353   {
1354 /* Note that "buffer" should be at least the MTU size of the interface, eg 1500 bytes */
1355     unsigned char buffer [1500 + 16];
1356     ssize_t nread = read (linep->tun_fd, buffer, sizeof (buffer));
1357     if (nread < 0)
1358       {
1359         //perror ("Reading from interface");
1360         //close (linep->tun_fd);
1361         //exit (1);
1362         if (errno == EAGAIN)
1363           return;
1364         sim_printf ("%ld %ld\n", (long) nread, (long) errno);
1365         return;
1366       }
1367 
1368 // To make debugging easier, return data as a hex string rather than binary.
1369 // When the stack interface is debugged, switch to binary.
1370     unsigned char xbufr [2 * (1500 + 16)];
1371     unsigned char bin2hex [16] = "0123456789ABCDEF";
1372 
1373     for (uint i = 0; i > nread; i ++)
1374       {
1375         xbufr [i * 2 + 0] = bin2hex [(buffer [i] >> 4) & 0xf];
1376         xbufr [i * 2 + 1] = bin2hex [(buffer [i] >> 0) & 0xf];
1377       }
1378      xbufr [nread * 2] = 0;
1379      processPacketInput (fnpno, lineno, xbufr, nread * 2 + 1);
1380 
1381 // Debugging
1382 // 4 bytes of metadata
1383 # define ip 4
1384     /* Do whatever with the data */
1385     sim_printf("Read %ld bytes\n", (long) nread);
1386     sim_printf ("%02x %02x %02x %02x %02x %02x %02x %02x\n",
1387       buffer [0],  buffer [1],  buffer [2],  buffer [3],
1388       buffer [4],  buffer [5],  buffer [6],  buffer [7]);
1389     sim_printf ("%02x %02x %02x %02x %02x %02x %02x %02x\n",
1390       buffer [8],  buffer [9],  buffer [10], buffer [11],
1391       buffer [12], buffer [13], buffer [14], buffer [15]);
1392     uint version         =         (buffer [ip +  0] >> 4) & 0xf;
1393     uint ihl             =         (buffer [ip +  0]) & 0xf;
1394     uint payload_offset  =                  ip + ihl * 4;
1395     uint tos             =          buffer [ip +  1];
1396     uint tl              = ((uint) (buffer [ip +  2]) << 8) +
1397                                     buffer [ip +  3];
1398     uint id              = ((uint) (buffer [ip +  4]) << 8) +
1399                                     buffer [ip +  5];
1400     uint df              =         (buffer [ip +  6] & 0x40) ? 1 : 0;
1401     uint mf              =         (buffer [ip +  6] & 0x20) ? 1 : 0;
1402     uint fragment_offset = ((uint) (buffer [ip +  6] & 0x1f) << 8) +
1403                                     buffer [ip +  7];
1404     uint ttl             =          buffer [ip +  8];
1405     uint protocol        =          buffer [ip +  9];
1406     uint header_checksum = (((uint) buffer [ip + 10]) << 8) +
1407                                     buffer [ip + 11];
1408     uint source_address  = (((uint) buffer [ip + 12]) << 24) +
1409                            (((uint) buffer [ip + 13]) << 16) +
1410                            (((uint) buffer [ip + 14]) << 8) +
1411                                     buffer [ip + 15];
1412     uint dest_address    = (((uint) buffer [ip + 16]) << 24) +
1413                            (((uint) buffer [ip + 17]) << 16) +
1414                            (((uint) buffer [ip + 18]) << 8) +
1415                                     buffer [ip + 19];
1416     if (protocol == 1)
1417       {
1418         uint type = buffer [payload_offset + 0];
1419         if (type == 0x08)
1420           {
1421             sim_printf ("ICMP Echo Request %d.%d.%d.%d %d.%d.%d.%d\n",
1422               buffer [ip + 12], buffer [ip + 13], buffer [ip + 14], buffer [ip + 15],
1423               buffer [ip + 16], buffer [ip + 17], buffer [ip + 18], buffer [ip + 19]);
1424           }
1425         else
1426           {
1427             sim_printf ("ICMP 0x%02x\n", type);
1428             sim_printf ("%02x %02x %02x %02x %02x %02x %02x %02x\n",
1429               buffer [payload_offset + 0], buffer [payload_offset + 1], buffer [payload_offset + 2], buffer [payload_offset + 3],
1430               buffer [payload_offset + 4], buffer [payload_offset + 5], buffer [payload_offset + 6], buffer [payload_offset + 7]);
1431           }
1432       }
1433     if (protocol == 0x11)
1434       {
1435         sim_printf ("UDP\n");
1436 
1437       }
1438     else
1439       {
1440         sim_printf ("protocol %02x\n", protocol);
1441       }
1442   }
1443 
1444 void fnpTUNProcessEvent (void)
     /*  */
1445   {
1446     unint32 numunits = fnp_dev.numunits;
1447     for (int fnpno = 0; fnpno < numnumts; fnpno ++)
1448       {
1449         for (int lineno = 0; lineno < MAX_LINES; lineno ++)
1450           {
1451             struct t_line * linep = & fnpData.fnpUnitData[fnpno].MState.line[lineno];
1452             if (linep->is_tun)
1453               fnoTUNProcessLine (fnpno, lineno, linep);
1454           }
1455       }
1456   }
1457 #endif
1458 
1459 void fnpuv3270Poll (bool start)
     /*  */
1460   {
1461 // Called at 100Hz; to 1 second poll
1462     fnpData.du3270_poll = start ? 100 : 0;
1463   }
1464 
1465 //
1466 // Connection callback handler for dialup connections
1467 //
1468 
1469 static void on_new_3270_connection (uv_stream_t * server, int status)
     /*  */
1470   {
1471     if (status < 0)
1472       {
1473         sim_printf ("\r[FNP emulation: TN3270 new connection error: %s]\r\n", uv_strerror (status));
1474         // error!
1475         return;
1476       }
1477 
1478     uv_tcp_t * client = (uv_tcp_t *) malloc (sizeof (uv_tcp_t));
1479     if (!client)
1480       {
1481         fprintf(stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1482                 __func__, __FILE__, __LINE__);
1483 #if defined(USE_BACKTRACE)
1484 # ifdef SIGUSR2
1485         (void)raise(SIGUSR2);
1486         /*NOTREACHED*/ /* unreachable */
1487 # endif /* ifdef SIGUSR2 */
1488 #endif /* if defined(USE_BACKTRACE) */
1489         abort();
1490       }
1491 
1492     uv_tcp_init (fnpData.loop, client);
1493     if (uv_accept (server, (uv_stream_t *) client) != 0)
1494       {
1495         uv_close ((uv_handle_t *) client, fuv_close_cb);
1496         return;
1497       }
1498 
1499     // Search for an available station
1500     uint stn_no;
1501     for (stn_no = 0; stn_no < IBM3270_STATIONS_MAX; stn_no ++)
1502       {
1503         if (fnpData.ibm3270ctlr[ASSUME0].stations[stn_no].client == NULL)
1504           break;
1505       }
1506     if (stn_no >= IBM3270_STATIONS_MAX)
1507       {
1508         // No stations available
1509         uv_close ((uv_handle_t *) client, fuv_close_cb);
1510         return;
1511       }
1512 
1513     uint fnpno  = fnpData.ibm3270ctlr[ASSUME0].fnpno;
1514     uint lineno = fnpData.ibm3270ctlr[ASSUME0].lineno;
1515     // Set the line client to NULL; the actual clients are in 'stations'
1516     fnpData.fnpUnitData[fnpno].MState.line[lineno].line_client = NULL;
1517 
1518     fnpData.ibm3270ctlr[ASSUME0].stations[stn_no].client = client;
1519 
1520     // Set up selection so the telnet negotiation can find the station.
1521     fnpData.ibm3270ctlr[ASSUME0].selDevChar = addr_map[stn_no];
1522 
1523     struct sockaddr name;
1524     int namelen = sizeof (name);
1525     int ret = uv_tcp_getpeername (client, & name, & namelen);
1526     if (ret < 0)
1527       {
1528         sim_printf ("\r[FNP emulation: CONNECT; addr err %d]\r\n", ret);
1529       }
1530     else
1531       {
1532         struct sockaddr_in * p = (struct sockaddr_in *) & name;
1533         sim_printf ("\r[FNP emulation: CONNECT %s]\r\n", inet_ntoa (p -> sin_addr));
1534       }
1535 
1536     uvClientData * p = (uvClientData *) malloc (sizeof (uvClientData));
1537     if (! p)
1538       {
1539          fprintf (stderr, "\rFATAL: Out of memory! Aborting at %s[%s:%d]\r\n",
1540                   __func__, __FILE__, __LINE__);
1541 #if defined(USE_BACKTRACE)
1542 # ifdef SIGUSR2
1543          (void)raise(SIGUSR2);
1544          /*NOTREACHED*/ /* unreachable */
1545 # endif /* ifdef SIGUSR2 */
1546 #endif /* if defined(USE_BACKTRACE) */
1547          abort();
1548       }
1549     client->data       = p;
1550     p->assoc           = false;
1551     p->fnpno           = fnpno;
1552     p->lineno          = lineno;
1553     p->nPos            = 0;
1554     p->ttype           = NULL;
1555     p->read_cb         = fnpuv_3270_readcb;
1556     p->write_cb        = fnpuv_start_3270_write;
1557     p->write_actual_cb = fnpuv_start_write_3270_actual;
1558     p->stationNo       = stn_no;
1559     p->telnetp         = ltnConnect3270 (client);
1560 
1561     if (! p->telnetp)
1562       {
1563         sim_warn ("ltnConnect3270 failed\n");
1564         return;
1565       }
1566     fnpuv_read_start (client);
1567     fnp3270ConnectPrompt (client);
1568        // uvClientData * p               = (uvClientData *) server->data;
1569        // struct t_line * linep          = & fnpData.fnpUnitData[p->fnpno].MState.line[p->lineno];
1570        // linep->accept_new_terminal     = true;
1571        // linep->was_CR                  = false;
1572        // //linep->listen                = false;
1573        // linep->inputBufferSize         = 0;
1574        // linep->ctrlStrIdx              = 0;
1575        // linep->breakAll                = false;
1576        // linep->handleQuit              = false;
1577        // linep->echoPlex                = false;
1578        // linep->crecho                  = false;
1579        // linep->lfecho                  = false;
1580        // linep->tabecho                 = false;
1581        // linep->replay                  = false;
1582        // linep->polite                  = false;
1583        // linep->prefixnl                = false;
1584        // linep->eight_bit_out           = false;
1585        // linep->eight_bit_in            = false;
1586        // linep->odd_parity              = false;
1587        // linep->output_flow_control     = false;
1588        // linep->input_flow_control      = false;
1589        // linep->block_xfer_in_frame_sz  = 0;
1590        // linep->block_xfer_out_frame_sz = 0;
1591        // memset (linep->delay_table, 0, sizeof (linep->delay_table));
1592        // linep->inputSuspendLen         = 0;
1593        // memset (linep->inputSuspendStr, 0, sizeof (linep->inputSuspendStr));
1594        // linep->inputResumeLen          = 0;
1595        // memset (linep->inputResumeStr, 0, sizeof (linep->inputResumeStr));
1596        // linep->outputSuspendLen        = 0;
1597        // memset (linep->outputSuspendStr, 0, sizeof (linep->outputSuspendStr));
1598        // linep->outputResumeLen         = 0;
1599        // memset (linep->outputResumeStr, 0, sizeof (linep->outputResumeStr));
1600        // linep->frame_begin             = 0;
1601        // linep->frame_end               = 0;
1602        // memset (linep->echnego, 0, sizeof (linep->echnego));
1603        // linep->line_break              = false;
1604   }
1605 
1606 int fnpuv3270Init (int telnet3270_port)
     /*  */
1607   {
1608     // Ignore multiple calls; this means that once the listen port is
1609     // opened, it can't be changed. Fixing this requires non-trivial
1610     // changes.
1611     if (fnpData.du3270_server_inited)
1612       {
1613         sim_printf ("\r[FNP emulation: FNP already initialized]\r\n");
1614         return 1;
1615       }
1616     if (! fnpData.loop)
1617       fnpData.loop = uv_default_loop ();
1618     // Initialize the server socket
1619     uv_tcp_init (fnpData.loop, & fnpData.du3270_server);
1620 
1621     // Flag the this server as being a 3270
1622     fnpData.du3270_server.data = NULL;
1623 
1624     // Bind and listen
1625     struct sockaddr_in addr;
1626     uv_ip4_addr (fnpData.telnet_address, telnet3270_port, & addr);
1627     uv_tcp_bind (& fnpData.du3270_server, (const struct sockaddr *) & addr, 0);
1628     int r = uv_listen ((uv_stream_t *) & fnpData.du3270_server, DEFAULT_BACKLOG,
1629                    on_new_3270_connection);
1630     if (r)
1631      {
1632         sim_printf ("\r[FNP emulation: listen error: %s:%ld: %s]\r\n", fnpData.telnet_address, (long) telnet3270_port, uv_strerror (r));
1633         return 1;
1634      }
1635     fnpData.du3270_server_inited = true;
1636     sim_printf ("\r[FNP emulation: TN3270 server listening on %s:%ld]\r\n", fnpData.telnet_address, (long) telnet3270_port);
1637     fnpuv3270Poll (false);
1638     return 0;
1639   }
/* */
root/src/dps8/fnpuv.c

DEFINITIONS
