xref: /third_party/curl/tests/server/tftpd.c (revision 13498266) 
1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 *
9 * Trivial file transfer protocol server.
10 *
11 * This code includes many modifications by Jim Guyton <guyton@rand-unix>
12 *
13 * This source file was started based on netkit-tftpd 0.17
14 * Heavily modified for curl's test suite
15 */
16
17/*
18 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
19 * Copyright (c) 1983, Regents of the University of California.
20 * All rights reserved.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the above copyright
26 *    notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 *    notice, this list of conditions and the following disclaimer in the
29 *    documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 *    must display the following acknowledgement:
32 *      This product includes software developed by the University of
33 *      California, Berkeley and its contributors.
34 * 4. Neither the name of the University nor the names of its contributors
35 *    may be used to endorse or promote products derived from this software
36 *    without specific prior written permission.
37 *
38 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
39 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
41 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
42 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
43 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
44 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
46 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
47 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48 * SUCH DAMAGE.
49 *
50 * SPDX-License-Identifier: BSD-4-Clause-UC
51 */
52
53#include "server_setup.h"
54
55#ifdef HAVE_SYS_IOCTL_H
56#include <sys/ioctl.h>
57#endif
58#include <signal.h>
59#ifdef HAVE_FCNTL_H
60#include <fcntl.h>
61#endif
62#ifdef HAVE_NETINET_IN_H
63#include <netinet/in.h>
64#endif
65#ifdef HAVE_ARPA_INET_H
66#include <arpa/inet.h>
67#endif
68#ifdef HAVE_NETDB_H
69#include <netdb.h>
70#endif
71#ifdef HAVE_SYS_FILIO_H
72/* FIONREAD on Solaris 7 */
73#include <sys/filio.h>
74#endif
75
76#include <setjmp.h>
77
78#ifdef HAVE_PWD_H
79#include <pwd.h>
80#endif
81
82#include <ctype.h>
83
84#define ENABLE_CURLX_PRINTF
85/* make the curlx header define all printf() functions to use the curlx_*
86   versions instead */
87#include "curlx.h" /* from the private lib dir */
88#include "getpart.h"
89#include "util.h"
90#include "server_sockaddr.h"
91#include "tftp.h"
92
93/* include memdebug.h last */
94#include "memdebug.h"
95
96/*****************************************************************************
97*                      STRUCT DECLARATIONS AND DEFINES                       *
98*****************************************************************************/
99
100#ifndef PKTSIZE
101#define PKTSIZE (SEGSIZE + 4)  /* SEGSIZE defined in arpa/tftp.h */
102#endif
103
104struct testcase {
105  char *buffer;   /* holds the file data to send to the client */
106  size_t bufsize; /* size of the data in buffer */
107  char *rptr;     /* read pointer into the buffer */
108  size_t rcount;  /* amount of data left to read of the file */
109  long testno;    /* test case number */
110  int ofile;      /* file descriptor for output file when uploading to us */
111
112  int writedelay; /* number of seconds between each packet */
113};
114
115struct formats {
116  const char *f_mode;
117  int f_convert;
118};
119
120struct errmsg {
121  int e_code;
122  const char *e_msg;
123};
124
125typedef union {
126  struct tftphdr hdr;
127  char storage[PKTSIZE];
128} tftphdr_storage_t;
129
130/*
131 * bf.counter values in range [-1 .. SEGSIZE] represents size of data in the
132 * bf.buf buffer. Additionally it can also hold flags BF_ALLOC or BF_FREE.
133 */
134
135struct bf {
136  int counter;            /* size of data in buffer, or flag */
137  tftphdr_storage_t buf;  /* room for data packet */
138};
139
140#define BF_ALLOC -3       /* alloc'd but not yet filled */
141#define BF_FREE  -2       /* free */
142
143#define opcode_RRQ   1
144#define opcode_WRQ   2
145#define opcode_DATA  3
146#define opcode_ACK   4
147#define opcode_ERROR 5
148
149#define TIMEOUT      5
150
151#undef MIN
152#define MIN(x,y) ((x)<(y)?(x):(y))
153
154#ifndef DEFAULT_LOGFILE
155#define DEFAULT_LOGFILE "log/tftpd.log"
156#endif
157
158#define REQUEST_DUMP  "server.input"
159
160#define DEFAULT_PORT 8999 /* UDP */
161
162/*****************************************************************************
163*                              GLOBAL VARIABLES                              *
164*****************************************************************************/
165
166static struct errmsg errmsgs[] = {
167  { EUNDEF,       "Undefined error code" },
168  { ENOTFOUND,    "File not found" },
169  { EACCESS,      "Access violation" },
170  { ENOSPACE,     "Disk full or allocation exceeded" },
171  { EBADOP,       "Illegal TFTP operation" },
172  { EBADID,       "Unknown transfer ID" },
173  { EEXISTS,      "File already exists" },
174  { ENOUSER,      "No such user" },
175  { -1,           0 }
176};
177
178static const struct formats formata[] = {
179  { "netascii",   1 },
180  { "octet",      0 },
181  { NULL,         0 }
182};
183
184static struct bf bfs[2];
185
186static int nextone;     /* index of next buffer to use */
187static int current;     /* index of buffer in use */
188
189                           /* control flags for crlf conversions */
190static int newline = 0;    /* fillbuf: in middle of newline expansion */
191static int prevchar = -1;  /* putbuf: previous char (cr check) */
192
193static tftphdr_storage_t buf;
194static tftphdr_storage_t ackbuf;
195
196static srvr_sockaddr_union_t from;
197static curl_socklen_t fromlen;
198
199static curl_socket_t peer = CURL_SOCKET_BAD;
200
201static unsigned int timeout;
202static unsigned int maxtimeout = 5 * TIMEOUT;
203
204#ifdef ENABLE_IPV6
205static bool use_ipv6 = FALSE;
206#endif
207static const char *ipv_inuse = "IPv4";
208
209const char *serverlogfile = DEFAULT_LOGFILE;
210static const char *logdir = "log";
211static char loglockfile[256];
212static const char *pidname = ".tftpd.pid";
213static const char *portname = NULL; /* none by default */
214static int serverlogslocked = 0;
215static int wrotepidfile = 0;
216static int wroteportfile = 0;
217
218#ifdef HAVE_SIGSETJMP
219static sigjmp_buf timeoutbuf;
220#endif
221
222#if defined(HAVE_ALARM) && defined(SIGALRM)
223static const unsigned int rexmtval = TIMEOUT;
224#endif
225
226/*****************************************************************************
227*                            FUNCTION PROTOTYPES                             *
228*****************************************************************************/
229
230static struct tftphdr *rw_init(int);
231
232static struct tftphdr *w_init(void);
233
234static struct tftphdr *r_init(void);
235
236static void read_ahead(struct testcase *test, int convert);
237
238static ssize_t write_behind(struct testcase *test, int convert);
239
240static int synchnet(curl_socket_t);
241
242static int do_tftp(struct testcase *test, struct tftphdr *tp, ssize_t size);
243
244static int validate_access(struct testcase *test, const char *fname, int mode);
245
246static void sendtftp(struct testcase *test, const struct formats *pf);
247
248static void recvtftp(struct testcase *test, const struct formats *pf);
249
250static void nak(int error);
251
252#if defined(HAVE_ALARM) && defined(SIGALRM)
253
254static void mysignal(int sig, void (*handler)(int));
255
256static void timer(int signum);
257
258static void justtimeout(int signum);
259
260#endif /* HAVE_ALARM && SIGALRM */
261
262/*****************************************************************************
263*                          FUNCTION IMPLEMENTATIONS                          *
264*****************************************************************************/
265
266#if defined(HAVE_ALARM) && defined(SIGALRM)
267
268/*
269 * Like signal(), but with well-defined semantics.
270 */
271static void mysignal(int sig, void (*handler)(int))
272{
273  struct sigaction sa;
274  memset(&sa, 0, sizeof(sa));
275  sa.sa_handler = handler;
276  sigaction(sig, &sa, NULL);
277}
278
279static void timer(int signum)
280{
281  (void)signum;
282
283  logmsg("alarm!");
284
285  timeout += rexmtval;
286  if(timeout >= maxtimeout) {
287    if(wrotepidfile) {
288      wrotepidfile = 0;
289      unlink(pidname);
290    }
291    if(wroteportfile) {
292      wroteportfile = 0;
293      unlink(portname);
294    }
295    if(serverlogslocked) {
296      serverlogslocked = 0;
297      clear_advisor_read_lock(loglockfile);
298    }
299    exit(1);
300  }
301#ifdef HAVE_SIGSETJMP
302  siglongjmp(timeoutbuf, 1);
303#endif
304}
305
306static void justtimeout(int signum)
307{
308  (void)signum;
309}
310
311#endif /* HAVE_ALARM && SIGALRM */
312
313/*
314 * init for either read-ahead or write-behind.
315 * zero for write-behind, one for read-head.
316 */
317static struct tftphdr *rw_init(int x)
318{
319  newline = 0;                    /* init crlf flag */
320  prevchar = -1;
321  bfs[0].counter =  BF_ALLOC;     /* pass out the first buffer */
322  current = 0;
323  bfs[1].counter = BF_FREE;
324  nextone = x;                    /* ahead or behind? */
325  return &bfs[0].buf.hdr;
326}
327
328static struct tftphdr *w_init(void)
329{
330  return rw_init(0); /* write-behind */
331}
332
333static struct tftphdr *r_init(void)
334{
335  return rw_init(1); /* read-ahead */
336}
337
338/* Have emptied current buffer by sending to net and getting ack.
339   Free it and return next buffer filled with data.
340 */
341static int readit(struct testcase *test, struct tftphdr **dpp,
342                  int convert /* if true, convert to ascii */)
343{
344  struct bf *b;
345
346  bfs[current].counter = BF_FREE; /* free old one */
347  current = !current;             /* "incr" current */
348
349  b = &bfs[current];              /* look at new buffer */
350  if(b->counter == BF_FREE)      /* if it's empty */
351    read_ahead(test, convert);    /* fill it */
352
353  *dpp = &b->buf.hdr;             /* set caller's ptr */
354  return b->counter;
355}
356
357/*
358 * fill the input buffer, doing ascii conversions if requested
359 * conversions are  lf -> cr, lf  and cr -> cr, nul
360 */
361static void read_ahead(struct testcase *test,
362                       int convert /* if true, convert to ascii */)
363{
364  int i;
365  char *p;
366  int c;
367  struct bf *b;
368  struct tftphdr *dp;
369
370  b = &bfs[nextone];              /* look at "next" buffer */
371  if(b->counter != BF_FREE)      /* nop if not free */
372    return;
373  nextone = !nextone;             /* "incr" next buffer ptr */
374
375  dp = &b->buf.hdr;
376
377  if(convert == 0) {
378    /* The former file reading code did this:
379       b->counter = read(fileno(file), dp->th_data, SEGSIZE); */
380    size_t copy_n = MIN(SEGSIZE, test->rcount);
381    memcpy(dp->th_data, test->rptr, copy_n);
382
383    /* decrease amount, advance pointer */
384    test->rcount -= copy_n;
385    test->rptr += copy_n;
386    b->counter = (int)copy_n;
387    return;
388  }
389
390  p = dp->th_data;
391  for(i = 0 ; i < SEGSIZE; i++) {
392    if(newline) {
393      if(prevchar == '\n')
394        c = '\n';       /* lf to cr,lf */
395      else
396        c = '\0';       /* cr to cr,nul */
397      newline = 0;
398    }
399    else {
400      if(test->rcount) {
401        c = test->rptr[0];
402        test->rptr++;
403        test->rcount--;
404      }
405      else
406        break;
407      if(c == '\n' || c == '\r') {
408        prevchar = c;
409        c = '\r';
410        newline = 1;
411      }
412    }
413    *p++ = (char)c;
414  }
415  b->counter = (int)(p - dp->th_data);
416}
417
418/* Update count associated with the buffer, get new buffer from the queue.
419   Calls write_behind only if next buffer not available.
420 */
421static int writeit(struct testcase *test, struct tftphdr * volatile *dpp,
422                   int ct, int convert)
423{
424  bfs[current].counter = ct;      /* set size of data to write */
425  current = !current;             /* switch to other buffer */
426  if(bfs[current].counter != BF_FREE)     /* if not free */
427    write_behind(test, convert);     /* flush it */
428  bfs[current].counter = BF_ALLOC;        /* mark as alloc'd */
429  *dpp =  &bfs[current].buf.hdr;
430  return ct;                      /* this is a lie of course */
431}
432
433/*
434 * Output a buffer to a file, converting from netascii if requested.
435 * CR, NUL -> CR  and CR, LF => LF.
436 * Note spec is undefined if we get CR as last byte of file or a
437 * CR followed by anything else.  In this case we leave it alone.
438 */
439static ssize_t write_behind(struct testcase *test, int convert)
440{
441  char *writebuf;
442  int count;
443  int ct;
444  char *p;
445  int c;                          /* current character */
446  struct bf *b;
447  struct tftphdr *dp;
448
449  b = &bfs[nextone];
450  if(b->counter < -1)            /* anything to flush? */
451    return 0;                     /* just nop if nothing to do */
452
453  if(!test->ofile) {
454    char outfile[256];
455    msnprintf(outfile, sizeof(outfile), "%s/upload.%ld", logdir, test->testno);
456#ifdef _WIN32
457    test->ofile = open(outfile, O_CREAT|O_RDWR|O_BINARY, 0777);
458#else
459    test->ofile = open(outfile, O_CREAT|O_RDWR, 0777);
460#endif
461    if(test->ofile == -1) {
462      logmsg("Couldn't create and/or open file %s for upload!", outfile);
463      return -1; /* failure! */
464    }
465  }
466
467  count = b->counter;             /* remember byte count */
468  b->counter = BF_FREE;           /* reset flag */
469  dp = &b->buf.hdr;
470  nextone = !nextone;             /* incr for next time */
471  writebuf = dp->th_data;
472
473  if(count <= 0)
474    return -1;                    /* nak logic? */
475
476  if(convert == 0)
477    return write(test->ofile, writebuf, count);
478
479  p = writebuf;
480  ct = count;
481  while(ct--) {                   /* loop over the buffer */
482    c = *p++;                     /* pick up a character */
483    if(prevchar == '\r') {        /* if prev char was cr */
484      if(c == '\n')               /* if have cr,lf then just */
485        lseek(test->ofile, -1, SEEK_CUR); /* smash lf on top of the cr */
486      else
487        if(c == '\0')             /* if have cr,nul then */
488          goto skipit;            /* just skip over the putc */
489      /* else just fall through and allow it */
490    }
491    /* formerly
492       putc(c, file); */
493    if(1 != write(test->ofile, &c, 1))
494      break;
495skipit:
496    prevchar = c;
497  }
498  return count;
499}
500
501/* When an error has occurred, it is possible that the two sides are out of
502 * synch.  Ie: that what I think is the other side's response to packet N is
503 * really their response to packet N-1.
504 *
505 * So, to try to prevent that, we flush all the input queued up for us on the
506 * network connection on our host.
507 *
508 * We return the number of packets we flushed (mostly for reporting when trace
509 * is active).
510 */
511
512static int synchnet(curl_socket_t f /* socket to flush */)
513{
514
515#if defined(HAVE_IOCTLSOCKET)
516  unsigned long i;
517#else
518  int i;
519#endif
520  int j = 0;
521  char rbuf[PKTSIZE];
522  srvr_sockaddr_union_t fromaddr;
523  curl_socklen_t fromaddrlen;
524
525  for(;;) {
526#if defined(HAVE_IOCTLSOCKET)
527    (void) ioctlsocket(f, FIONREAD, &i);
528#else
529    (void) ioctl(f, FIONREAD, &i);
530#endif
531    if(i) {
532      j++;
533#ifdef ENABLE_IPV6
534      if(!use_ipv6)
535#endif
536        fromaddrlen = sizeof(fromaddr.sa4);
537#ifdef ENABLE_IPV6
538      else
539        fromaddrlen = sizeof(fromaddr.sa6);
540#endif
541      (void) recvfrom(f, rbuf, sizeof(rbuf), 0,
542                      &fromaddr.sa, &fromaddrlen);
543    }
544    else
545      break;
546  }
547  return j;
548}
549
550int main(int argc, char **argv)
551{
552  srvr_sockaddr_union_t me;
553  struct tftphdr *tp;
554  ssize_t n = 0;
555  int arg = 1;
556  unsigned short port = DEFAULT_PORT;
557  curl_socket_t sock = CURL_SOCKET_BAD;
558  int flag;
559  int rc;
560  int error;
561  struct testcase test;
562  int result = 0;
563
564  memset(&test, 0, sizeof(test));
565
566  while(argc>arg) {
567    if(!strcmp("--version", argv[arg])) {
568      printf("tftpd IPv4%s\n",
569#ifdef ENABLE_IPV6
570             "/IPv6"
571#else
572             ""
573#endif
574             );
575      return 0;
576    }
577    else if(!strcmp("--pidfile", argv[arg])) {
578      arg++;
579      if(argc>arg)
580        pidname = argv[arg++];
581    }
582    else if(!strcmp("--portfile", argv[arg])) {
583      arg++;
584      if(argc>arg)
585        portname = argv[arg++];
586    }
587    else if(!strcmp("--logfile", argv[arg])) {
588      arg++;
589      if(argc>arg)
590        serverlogfile = argv[arg++];
591    }
592    else if(!strcmp("--logdir", argv[arg])) {
593      arg++;
594      if(argc>arg)
595        logdir = argv[arg++];
596    }
597    else if(!strcmp("--ipv4", argv[arg])) {
598#ifdef ENABLE_IPV6
599      ipv_inuse = "IPv4";
600      use_ipv6 = FALSE;
601#endif
602      arg++;
603    }
604    else if(!strcmp("--ipv6", argv[arg])) {
605#ifdef ENABLE_IPV6
606      ipv_inuse = "IPv6";
607      use_ipv6 = TRUE;
608#endif
609      arg++;
610    }
611    else if(!strcmp("--port", argv[arg])) {
612      arg++;
613      if(argc>arg) {
614        char *endptr;
615        unsigned long ulnum = strtoul(argv[arg], &endptr, 10);
616        port = curlx_ultous(ulnum);
617        arg++;
618      }
619    }
620    else if(!strcmp("--srcdir", argv[arg])) {
621      arg++;
622      if(argc>arg) {
623        path = argv[arg];
624        arg++;
625      }
626    }
627    else {
628      puts("Usage: tftpd [option]\n"
629           " --version\n"
630           " --logfile [file]\n"
631           " --logdir [directory]\n"
632           " --pidfile [file]\n"
633           " --portfile [file]\n"
634           " --ipv4\n"
635           " --ipv6\n"
636           " --port [port]\n"
637           " --srcdir [path]");
638      return 0;
639    }
640  }
641
642  msnprintf(loglockfile, sizeof(loglockfile), "%s/%s/tftp-%s.lock",
643            logdir, SERVERLOGS_LOCKDIR, ipv_inuse);
644
645#ifdef _WIN32
646  win32_init();
647  atexit(win32_cleanup);
648#endif
649
650  install_signal_handlers(true);
651
652#ifdef ENABLE_IPV6
653  if(!use_ipv6)
654#endif
655    sock = socket(AF_INET, SOCK_DGRAM, 0);
656#ifdef ENABLE_IPV6
657  else
658    sock = socket(AF_INET6, SOCK_DGRAM, 0);
659#endif
660
661  if(CURL_SOCKET_BAD == sock) {
662    error = SOCKERRNO;
663    logmsg("Error creating socket: (%d) %s", error, sstrerror(error));
664    result = 1;
665    goto tftpd_cleanup;
666  }
667
668  flag = 1;
669  if(0 != setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
670            (void *)&flag, sizeof(flag))) {
671    error = SOCKERRNO;
672    logmsg("setsockopt(SO_REUSEADDR) failed with error: (%d) %s",
673           error, sstrerror(error));
674    result = 1;
675    goto tftpd_cleanup;
676  }
677
678#ifdef ENABLE_IPV6
679  if(!use_ipv6) {
680#endif
681    memset(&me.sa4, 0, sizeof(me.sa4));
682    me.sa4.sin_family = AF_INET;
683    me.sa4.sin_addr.s_addr = INADDR_ANY;
684    me.sa4.sin_port = htons(port);
685    rc = bind(sock, &me.sa, sizeof(me.sa4));
686#ifdef ENABLE_IPV6
687  }
688  else {
689    memset(&me.sa6, 0, sizeof(me.sa6));
690    me.sa6.sin6_family = AF_INET6;
691    me.sa6.sin6_addr = in6addr_any;
692    me.sa6.sin6_port = htons(port);
693    rc = bind(sock, &me.sa, sizeof(me.sa6));
694  }
695#endif /* ENABLE_IPV6 */
696  if(0 != rc) {
697    error = SOCKERRNO;
698    logmsg("Error binding socket on port %hu: (%d) %s", port, error,
699           sstrerror(error));
700    result = 1;
701    goto tftpd_cleanup;
702  }
703
704  if(!port) {
705    /* The system was supposed to choose a port number, figure out which
706       port we actually got and update the listener port value with it. */
707    curl_socklen_t la_size;
708    srvr_sockaddr_union_t localaddr;
709#ifdef ENABLE_IPV6
710    if(!use_ipv6)
711#endif
712      la_size = sizeof(localaddr.sa4);
713#ifdef ENABLE_IPV6
714    else
715      la_size = sizeof(localaddr.sa6);
716#endif
717    memset(&localaddr.sa, 0, (size_t)la_size);
718    if(getsockname(sock, &localaddr.sa, &la_size) < 0) {
719      error = SOCKERRNO;
720      logmsg("getsockname() failed with error: (%d) %s",
721             error, sstrerror(error));
722      sclose(sock);
723      goto tftpd_cleanup;
724    }
725    switch(localaddr.sa.sa_family) {
726    case AF_INET:
727      port = ntohs(localaddr.sa4.sin_port);
728      break;
729#ifdef ENABLE_IPV6
730    case AF_INET6:
731      port = ntohs(localaddr.sa6.sin6_port);
732      break;
733#endif
734    default:
735      break;
736    }
737    if(!port) {
738      /* Real failure, listener port shall not be zero beyond this point. */
739      logmsg("Apparently getsockname() succeeded, with listener port zero.");
740      logmsg("A valid reason for this failure is a binary built without");
741      logmsg("proper network library linkage. This might not be the only");
742      logmsg("reason, but double check it before anything else.");
743      result = 2;
744      goto tftpd_cleanup;
745    }
746  }
747
748  wrotepidfile = write_pidfile(pidname);
749  if(!wrotepidfile) {
750    result = 1;
751    goto tftpd_cleanup;
752  }
753
754  if(portname) {
755    wroteportfile = write_portfile(portname, port);
756    if(!wroteportfile) {
757      result = 1;
758      goto tftpd_cleanup;
759    }
760  }
761
762  logmsg("Running %s version on port UDP/%d", ipv_inuse, (int)port);
763
764  for(;;) {
765    fromlen = sizeof(from);
766#ifdef ENABLE_IPV6
767    if(!use_ipv6)
768#endif
769      fromlen = sizeof(from.sa4);
770#ifdef ENABLE_IPV6
771    else
772      fromlen = sizeof(from.sa6);
773#endif
774    n = (ssize_t)recvfrom(sock, &buf.storage[0], sizeof(buf.storage), 0,
775                          &from.sa, &fromlen);
776    if(got_exit_signal)
777      break;
778    if(n < 0) {
779      logmsg("recvfrom");
780      result = 3;
781      break;
782    }
783
784    set_advisor_read_lock(loglockfile);
785    serverlogslocked = 1;
786
787#ifdef ENABLE_IPV6
788    if(!use_ipv6) {
789#endif
790      from.sa4.sin_family = AF_INET;
791      peer = socket(AF_INET, SOCK_DGRAM, 0);
792      if(CURL_SOCKET_BAD == peer) {
793        logmsg("socket");
794        result = 2;
795        break;
796      }
797      if(connect(peer, &from.sa, sizeof(from.sa4)) < 0) {
798        logmsg("connect: fail");
799        result = 1;
800        break;
801      }
802#ifdef ENABLE_IPV6
803    }
804    else {
805      from.sa6.sin6_family = AF_INET6;
806      peer = socket(AF_INET6, SOCK_DGRAM, 0);
807      if(CURL_SOCKET_BAD == peer) {
808        logmsg("socket");
809        result = 2;
810        break;
811      }
812      if(connect(peer, &from.sa, sizeof(from.sa6)) < 0) {
813        logmsg("connect: fail");
814        result = 1;
815        break;
816      }
817    }
818#endif
819
820    maxtimeout = 5*TIMEOUT;
821
822    tp = &buf.hdr;
823    tp->th_opcode = ntohs(tp->th_opcode);
824    if(tp->th_opcode == opcode_RRQ || tp->th_opcode == opcode_WRQ) {
825      memset(&test, 0, sizeof(test));
826      if(do_tftp(&test, tp, n) < 0)
827        break;
828      free(test.buffer);
829    }
830    sclose(peer);
831    peer = CURL_SOCKET_BAD;
832
833    if(got_exit_signal)
834      break;
835
836    if(serverlogslocked) {
837      serverlogslocked = 0;
838      clear_advisor_read_lock(loglockfile);
839    }
840
841    logmsg("end of one transfer");
842
843  }
844
845tftpd_cleanup:
846
847  if(test.ofile > 0)
848    close(test.ofile);
849
850  if((peer != sock) && (peer != CURL_SOCKET_BAD))
851    sclose(peer);
852
853  if(sock != CURL_SOCKET_BAD)
854    sclose(sock);
855
856  if(got_exit_signal)
857    logmsg("signalled to die");
858
859  if(wrotepidfile)
860    unlink(pidname);
861  if(wroteportfile)
862    unlink(portname);
863
864  if(serverlogslocked) {
865    serverlogslocked = 0;
866    clear_advisor_read_lock(loglockfile);
867  }
868
869  restore_signal_handlers(true);
870
871  if(got_exit_signal) {
872    logmsg("========> %s tftpd (port: %d pid: %ld) exits with signal (%d)",
873           ipv_inuse, (int)port, (long)getpid(), exit_signal);
874    /*
875     * To properly set the return status of the process we
876     * must raise the same signal SIGINT or SIGTERM that we
877     * caught and let the old handler take care of it.
878     */
879    raise(exit_signal);
880  }
881
882  logmsg("========> tftpd quits");
883  return result;
884}
885
886/*
887 * Handle initial connection protocol.
888 */
889static int do_tftp(struct testcase *test, struct tftphdr *tp, ssize_t size)
890{
891  char *cp;
892  int first = 1, ecode;
893  const struct formats *pf;
894  char *filename, *mode = NULL;
895#ifdef USE_WINSOCK
896  DWORD recvtimeout, recvtimeoutbak;
897#endif
898  const char *option = "mode"; /* mode is implicit */
899  int toggle = 1;
900  FILE *server;
901  char dumpfile[256];
902
903  msnprintf(dumpfile, sizeof(dumpfile), "%s/%s", logdir, REQUEST_DUMP);
904
905  /* Open request dump file. */
906  server = fopen(dumpfile, "ab");
907  if(!server) {
908    int error = errno;
909    logmsg("fopen() failed with error: %d %s", error, strerror(error));
910    logmsg("Error opening file: %s", dumpfile);
911    return -1;
912  }
913
914  /* store input protocol */
915  fprintf(server, "opcode = %x\n", tp->th_opcode);
916
917  cp = (char *)&tp->th_stuff;
918  filename = cp;
919  do {
920    bool endofit = true;
921    while(cp < &buf.storage[size]) {
922      if(*cp == '\0') {
923        endofit = false;
924        break;
925      }
926      cp++;
927    }
928    if(endofit)
929      /* no more options */
930      break;
931
932    /* before increasing pointer, make sure it is still within the legal
933       space */
934    if((cp + 1) < &buf.storage[size]) {
935      ++cp;
936      if(first) {
937        /* store the mode since we need it later */
938        mode = cp;
939        first = 0;
940      }
941      if(toggle)
942        /* name/value pair: */
943        fprintf(server, "%s = %s\n", option, cp);
944      else {
945        /* store the name pointer */
946        option = cp;
947      }
948      toggle ^= 1;
949    }
950    else
951      /* No more options */
952      break;
953  } while(1);
954
955  if(*cp) {
956    nak(EBADOP);
957    fclose(server);
958    return 3;
959  }
960
961  /* store input protocol */
962  fprintf(server, "filename = %s\n", filename);
963
964  for(cp = mode; cp && *cp; cp++)
965    if(ISUPPER(*cp))
966      *cp = (char)tolower((int)*cp);
967
968  /* store input protocol */
969  fclose(server);
970
971  for(pf = formata; pf->f_mode; pf++)
972    if(strcmp(pf->f_mode, mode) == 0)
973      break;
974  if(!pf->f_mode) {
975    nak(EBADOP);
976    return 2;
977  }
978  ecode = validate_access(test, filename, tp->th_opcode);
979  if(ecode) {
980    nak(ecode);
981    return 1;
982  }
983
984#ifdef USE_WINSOCK
985  recvtimeout = sizeof(recvtimeoutbak);
986  getsockopt(peer, SOL_SOCKET, SO_RCVTIMEO,
987             (char *)&recvtimeoutbak, (int *)&recvtimeout);
988  recvtimeout = TIMEOUT*1000;
989  setsockopt(peer, SOL_SOCKET, SO_RCVTIMEO,
990             (const char *)&recvtimeout, sizeof(recvtimeout));
991#endif
992
993  if(tp->th_opcode == opcode_WRQ)
994    recvtftp(test, pf);
995  else
996    sendtftp(test, pf);
997
998#ifdef USE_WINSOCK
999  recvtimeout = recvtimeoutbak;
1000  setsockopt(peer, SOL_SOCKET, SO_RCVTIMEO,
1001             (const char *)&recvtimeout, sizeof(recvtimeout));
1002#endif
1003
1004  return 0;
1005}
1006
1007/* Based on the testno, parse the correct server commands. */
1008static int parse_servercmd(struct testcase *req)
1009{
1010  FILE *stream;
1011  int error;
1012
1013  stream = test2fopen(req->testno, logdir);
1014  if(!stream) {
1015    error = errno;
1016    logmsg("fopen() failed with error: %d %s", error, strerror(error));
1017    logmsg("  Couldn't open test file %ld", req->testno);
1018    return 1; /* done */
1019  }
1020  else {
1021    char *orgcmd = NULL;
1022    char *cmd = NULL;
1023    size_t cmdsize = 0;
1024    int num = 0;
1025
1026    /* get the custom server control "commands" */
1027    error = getpart(&orgcmd, &cmdsize, "reply", "servercmd", stream);
1028    fclose(stream);
1029    if(error) {
1030      logmsg("getpart() failed with error: %d", error);
1031      return 1; /* done */
1032    }
1033
1034    cmd = orgcmd;
1035    while(cmd && cmdsize) {
1036      char *check;
1037      if(1 == sscanf(cmd, "writedelay: %d", &num)) {
1038        logmsg("instructed to delay %d secs between packets", num);
1039        req->writedelay = num;
1040      }
1041      else {
1042        logmsg("Unknown <servercmd> instruction found: %s", cmd);
1043      }
1044      /* try to deal with CRLF or just LF */
1045      check = strchr(cmd, '\r');
1046      if(!check)
1047        check = strchr(cmd, '\n');
1048
1049      if(check) {
1050        /* get to the letter following the newline */
1051        while((*check == '\r') || (*check == '\n'))
1052          check++;
1053
1054        if(!*check)
1055          /* if we reached a zero, get out */
1056          break;
1057        cmd = check;
1058      }
1059      else
1060        break;
1061    }
1062    free(orgcmd);
1063  }
1064
1065  return 0; /* OK! */
1066}
1067
1068
1069/*
1070 * Validate file access.
1071 */
1072static int validate_access(struct testcase *test,
1073                           const char *filename, int mode)
1074{
1075  char *ptr;
1076
1077  logmsg("trying to get file: %s mode %x", filename, mode);
1078
1079  if(!strncmp("verifiedserver", filename, 14)) {
1080    char weare[128];
1081    size_t count = msnprintf(weare, sizeof(weare), "WE ROOLZ: %"
1082                             CURL_FORMAT_CURL_OFF_T "\r\n", our_getpid());
1083
1084    logmsg("Are-we-friendly question received");
1085    test->buffer = strdup(weare);
1086    test->rptr = test->buffer; /* set read pointer */
1087    test->bufsize = count;    /* set total count */
1088    test->rcount = count;     /* set data left to read */
1089    return 0; /* fine */
1090  }
1091
1092  /* find the last slash */
1093  ptr = strrchr(filename, '/');
1094
1095  if(ptr) {
1096    char partbuf[80]="data";
1097    long partno;
1098    long testno;
1099    FILE *stream;
1100
1101    ptr++; /* skip the slash */
1102
1103    /* skip all non-numericals following the slash */
1104    while(*ptr && !ISDIGIT(*ptr))
1105      ptr++;
1106
1107    /* get the number */
1108    testno = strtol(ptr, &ptr, 10);
1109
1110    if(testno > 10000) {
1111      partno = testno % 10000;
1112      testno /= 10000;
1113    }
1114    else
1115      partno = 0;
1116
1117
1118    logmsg("requested test number %ld part %ld", testno, partno);
1119
1120    test->testno = testno;
1121
1122    (void)parse_servercmd(test);
1123
1124    stream = test2fopen(testno, logdir);
1125
1126    if(0 != partno)
1127      msnprintf(partbuf, sizeof(partbuf), "data%ld", partno);
1128
1129    if(!stream) {
1130      int error = errno;
1131      logmsg("fopen() failed with error: %d %s", error, strerror(error));
1132      logmsg("Couldn't open test file for test: %ld", testno);
1133      return EACCESS;
1134    }
1135    else {
1136      size_t count;
1137      int error = getpart(&test->buffer, &count, "reply", partbuf, stream);
1138      fclose(stream);
1139      if(error) {
1140        logmsg("getpart() failed with error: %d", error);
1141        return EACCESS;
1142      }
1143      if(test->buffer) {
1144        test->rptr = test->buffer; /* set read pointer */
1145        test->bufsize = count;    /* set total count */
1146        test->rcount = count;     /* set data left to read */
1147      }
1148      else
1149        return EACCESS;
1150    }
1151  }
1152  else {
1153    logmsg("no slash found in path");
1154    return EACCESS; /* failure */
1155  }
1156
1157  logmsg("file opened and all is good");
1158  return 0;
1159}
1160
1161/*
1162 * Send the requested file.
1163 */
1164static void sendtftp(struct testcase *test, const struct formats *pf)
1165{
1166  int size;
1167  ssize_t n;
1168  /* These are volatile to live through a siglongjmp */
1169  volatile unsigned short sendblock; /* block count */
1170  struct tftphdr * volatile sdp = r_init(); /* data buffer */
1171  struct tftphdr * const sap = &ackbuf.hdr; /* ack buffer */
1172
1173  sendblock = 1;
1174#if defined(HAVE_ALARM) && defined(SIGALRM)
1175  mysignal(SIGALRM, timer);
1176#endif
1177  do {
1178    size = readit(test, (struct tftphdr **)&sdp, pf->f_convert);
1179    if(size < 0) {
1180      nak(errno + 100);
1181      return;
1182    }
1183    sdp->th_opcode = htons((unsigned short)opcode_DATA);
1184    sdp->th_block = htons(sendblock);
1185    timeout = 0;
1186#ifdef HAVE_SIGSETJMP
1187    (void) sigsetjmp(timeoutbuf, 1);
1188#endif
1189    if(test->writedelay) {
1190      logmsg("Pausing %d seconds before %d bytes", test->writedelay,
1191             size);
1192      wait_ms(1000*test->writedelay);
1193    }
1194
1195send_data:
1196    logmsg("write");
1197    if(swrite(peer, sdp, size + 4) != size + 4) {
1198      logmsg("write: fail");
1199      return;
1200    }
1201    read_ahead(test, pf->f_convert);
1202    for(;;) {
1203#ifdef HAVE_ALARM
1204      alarm(rexmtval);        /* read the ack */
1205#endif
1206      logmsg("read");
1207      n = sread(peer, &ackbuf.storage[0], sizeof(ackbuf.storage));
1208      logmsg("read: %zd", n);
1209#ifdef HAVE_ALARM
1210      alarm(0);
1211#endif
1212      if(got_exit_signal)
1213        return;
1214      if(n < 0) {
1215        logmsg("read: fail");
1216        return;
1217      }
1218      sap->th_opcode = ntohs((unsigned short)sap->th_opcode);
1219      sap->th_block = ntohs(sap->th_block);
1220
1221      if(sap->th_opcode == opcode_ERROR) {
1222        logmsg("got ERROR");
1223        return;
1224      }
1225
1226      if(sap->th_opcode == opcode_ACK) {
1227        if(sap->th_block == sendblock) {
1228          break;
1229        }
1230        /* Re-synchronize with the other side */
1231        (void) synchnet(peer);
1232        if(sap->th_block == (sendblock-1)) {
1233          goto send_data;
1234        }
1235      }
1236
1237    }
1238    sendblock++;
1239  } while(size == SEGSIZE);
1240}
1241
1242/*
1243 * Receive a file.
1244 */
1245static void recvtftp(struct testcase *test, const struct formats *pf)
1246{
1247  ssize_t n, size;
1248  /* These are volatile to live through a siglongjmp */
1249  volatile unsigned short recvblock; /* block count */
1250  struct tftphdr * volatile rdp;     /* data buffer */
1251  struct tftphdr *rap;      /* ack buffer */
1252
1253  recvblock = 0;
1254  rdp = w_init();
1255#if defined(HAVE_ALARM) && defined(SIGALRM)
1256  mysignal(SIGALRM, timer);
1257#endif
1258  rap = &ackbuf.hdr;
1259  do {
1260    timeout = 0;
1261    rap->th_opcode = htons((unsigned short)opcode_ACK);
1262    rap->th_block = htons(recvblock);
1263    recvblock++;
1264#ifdef HAVE_SIGSETJMP
1265    (void) sigsetjmp(timeoutbuf, 1);
1266#endif
1267send_ack:
1268    logmsg("write");
1269    if(swrite(peer, &ackbuf.storage[0], 4) != 4) {
1270      logmsg("write: fail");
1271      goto abort;
1272    }
1273    write_behind(test, pf->f_convert);
1274    for(;;) {
1275#ifdef HAVE_ALARM
1276      alarm(rexmtval);
1277#endif
1278      logmsg("read");
1279      n = sread(peer, rdp, PKTSIZE);
1280      logmsg("read: %zd", n);
1281#ifdef HAVE_ALARM
1282      alarm(0);
1283#endif
1284      if(got_exit_signal)
1285        goto abort;
1286      if(n < 0) {                       /* really? */
1287        logmsg("read: fail");
1288        goto abort;
1289      }
1290      rdp->th_opcode = ntohs((unsigned short)rdp->th_opcode);
1291      rdp->th_block = ntohs(rdp->th_block);
1292      if(rdp->th_opcode == opcode_ERROR)
1293        goto abort;
1294      if(rdp->th_opcode == opcode_DATA) {
1295        if(rdp->th_block == recvblock) {
1296          break;                         /* normal */
1297        }
1298        /* Re-synchronize with the other side */
1299        (void) synchnet(peer);
1300        if(rdp->th_block == (recvblock-1))
1301          goto send_ack;                 /* rexmit */
1302      }
1303    }
1304
1305    size = writeit(test, &rdp, (int)(n - 4), pf->f_convert);
1306    if(size != (n-4)) {                 /* ahem */
1307      if(size < 0)
1308        nak(errno + 100);
1309      else
1310        nak(ENOSPACE);
1311      goto abort;
1312    }
1313  } while(size == SEGSIZE);
1314  write_behind(test, pf->f_convert);
1315  /* close the output file as early as possible after upload completion */
1316  if(test->ofile > 0) {
1317    close(test->ofile);
1318    test->ofile = 0;
1319  }
1320
1321  rap->th_opcode = htons((unsigned short)opcode_ACK);  /* send the "final"
1322                                                          ack */
1323  rap->th_block = htons(recvblock);
1324  (void) swrite(peer, &ackbuf.storage[0], 4);
1325#if defined(HAVE_ALARM) && defined(SIGALRM)
1326  mysignal(SIGALRM, justtimeout);        /* just abort read on timeout */
1327  alarm(rexmtval);
1328#endif
1329  /* normally times out and quits */
1330  n = sread(peer, &buf.storage[0], sizeof(buf.storage));
1331#ifdef HAVE_ALARM
1332  alarm(0);
1333#endif
1334  if(got_exit_signal)
1335    goto abort;
1336  if(n >= 4 &&                               /* if read some data */
1337     rdp->th_opcode == opcode_DATA &&        /* and got a data block */
1338     recvblock == rdp->th_block) {           /* then my last ack was lost */
1339    (void) swrite(peer, &ackbuf.storage[0], 4);  /* resend final ack */
1340  }
1341abort:
1342  /* make sure the output file is closed in case of abort */
1343  if(test->ofile > 0) {
1344    close(test->ofile);
1345    test->ofile = 0;
1346  }
1347  return;
1348}
1349
1350/*
1351 * Send a nak packet (error message).  Error code passed in is one of the
1352 * standard TFTP codes, or a Unix errno offset by 100.
1353 */
1354static void nak(int error)
1355{
1356  struct tftphdr *tp;
1357  int length;
1358  struct errmsg *pe;
1359
1360  tp = &buf.hdr;
1361  tp->th_opcode = htons((unsigned short)opcode_ERROR);
1362  tp->th_code = htons((unsigned short)error);
1363  for(pe = errmsgs; pe->e_code >= 0; pe++)
1364    if(pe->e_code == error)
1365      break;
1366  if(pe->e_code < 0) {
1367    pe->e_msg = strerror(error - 100);
1368    tp->th_code = EUNDEF;   /* set 'undef' errorcode */
1369  }
1370  length = (int)strlen(pe->e_msg);
1371
1372  /* we use memcpy() instead of strcpy() in order to avoid buffer overflow
1373   * report from glibc with FORTIFY_SOURCE */
1374  memcpy(tp->th_msg, pe->e_msg, length + 1);
1375  length += 5;
1376  if(swrite(peer, &buf.storage[0], length) != length)
1377    logmsg("nak: fail\n");
1378}
1379