2 * Network Block Device - server
4 * Copyright 1996-1998 Pavel Machek, distribute under GPL
5 * <pavel@atrey.karlin.mff.cuni.cz>
6 * Copyright 2001-2004 Wouter Verhelst <wouter@debian.org>
7 * Copyright 2002 Anton Altaparmakov <aia21@cam.ac.uk>
9 * Version 1.0 - hopefully 64-bit-clean
10 * Version 1.1 - merging enhancements from Josh Parsons, <josh@coombs.anu.edu.au>
11 * Version 1.2 - autodetect size of block devices, thanx to Peter T. Breuer" <ptb@it.uc3m.es>
12 * Version 1.5 - can compile on Unix systems that don't have 64 bit integer
13 * type, or don't have 64 bit file offsets by defining FS_32BIT
14 * in compile options for nbd-server *only*. This can be done
15 * with make FSCHOICE=-DFS_32BIT nbd-server. (I don't have the
16 * original autoconf input file, or I would make it a configure
17 * option.) Ken Yap <ken@nlc.net.au>.
18 * Version 1.6 - fix autodetection of block device size and really make 64 bit
19 * clean on 32 bit machines. Anton Altaparmakov <aia21@cam.ac.uk>
20 * Version 2.0 - Version synchronised with client
21 * Version 2.1 - Reap zombie client processes when they exit. Removed
22 * (uncommented) the _IO magic, it's no longer necessary. Wouter
23 * Verhelst <wouter@debian.org>
24 * Version 2.2 - Auto switch to read-only mode (usefull for floppies).
25 * Version 2.3 - Fixed code so that Large File Support works. This
26 * removes the FS_32BIT compile-time directive; define
27 * _FILE_OFFSET_BITS=64 and _LARGEFILE_SOURCE if you used to be
28 * using FS_32BIT. This will allow you to use files >2GB instead of
29 * having to use the -m option. Wouter Verhelst <wouter@debian.org>
30 * Version 2.4 - Added code to keep track of children, so that we can
31 * properly kill them from initscripts. Add a call to daemon(),
32 * so that processes don't think they have to wait for us, which is
33 * interesting for initscripts as well. Wouter Verhelst
35 * Version 2.5 - Bugfix release: forgot to reset child_arraysize to
36 * zero after fork()ing, resulting in nbd-server going berserk
37 * when it receives a signal with at least one child open. Wouter
38 * Verhelst <wouter@debian.org>
39 * 10/10/2003 - Added socket option SO_KEEPALIVE (sf.net bug 819235);
40 * rectified type of mainloop::size_host (sf.net bugs 814435 and
41 * 817385); close the PID file after writing to it, so that the
42 * daemon can actually be found. Wouter Verhelst
44 * 10/10/2003 - Size of the data "size_host" was wrong and so was not
45 * correctly put in network endianness. Many types were corrected
46 * (size_t and off_t instead of int). <vspaceg@sourceforge.net>
47 * Version 2.6 - Some code cleanup.
48 * Version 2.7 - Better build system.
49 * 11/02/2004 - Doxygenified the source, modularized it a bit. Needs a
50 * lot more work, but this is a start. Wouter Verhelst
54 /* Includes LFS defines, which defines behaviours of some of the following
55 * headers, so must come before those */
58 #include <sys/types.h>
59 #include <sys/socket.h>
61 #include <sys/select.h> /* select */
62 #include <sys/wait.h> /* wait */
63 #ifdef HAVE_SYS_IOCTL_H
64 #include <sys/ioctl.h>
66 #include <sys/param.h>
67 #ifdef HAVE_SYS_MOUNT_H
68 #include <sys/mount.h> /* For BLKGETSIZE */
70 #include <signal.h> /* sigaction */
72 #include <netinet/tcp.h>
73 #include <netinet/in.h> /* sockaddr_in, htons, in_addr */
74 #include <netdb.h> /* hostent, gethostby*, getservby* */
81 #include <arpa/inet.h>
91 /* used in cliserv.h, so must come first */
92 #define MY_NAME "nbd_server"
95 /** Default position of the config file */
97 #define SYSCONFDIR "/etc"
99 #define CFILE SYSCONFDIR "/nbd-server/config"
101 /** Where our config file actually is */
102 gchar* config_file_pos;
104 /** What user we're running as */
106 /** What group we're running as */
107 gchar* rungroup=NULL;
109 /** Logging macros, now nothing goes to syslog unless you say ISSERVER */
111 #define msg2(a,b) syslog(a,b)
112 #define msg3(a,b,c) syslog(a,b,c)
113 #define msg4(a,b,c,d) syslog(a,b,c,d)
115 #define msg2(a,b) g_message(b)
116 #define msg3(a,b,c) g_message(b,c)
117 #define msg4(a,b,c,d) g_message(b,c,d)
120 /* Debugging macros */
123 #define DEBUG( a ) printf( a )
124 #define DEBUG2( a,b ) printf( a,b )
125 #define DEBUG3( a,b,c ) printf( a,b,c )
126 #define DEBUG4( a,b,c,d ) printf( a,b,c,d )
129 #define DEBUG2( a,b )
130 #define DEBUG3( a,b,c )
131 #define DEBUG4( a,b,c,d )
133 #ifndef PACKAGE_VERSION
134 #define PACKAGE_VERSION ""
137 * The highest value a variable of type off_t can reach. This is a signed
138 * integer, so set all bits except for the leftmost one.
140 #define OFFT_MAX ~((off_t)1<<(sizeof(off_t)*8-1))
141 #define LINELEN 256 /**< Size of static buffer used to read the
142 authorization file (yuck) */
143 #define BUFSIZE (1024*1024) /**< Size of buffer that can hold requests */
144 #define DIFFPAGESIZE 4096 /**< diff file uses those chunks */
145 #define F_READONLY 1 /**< flag to tell us a file is readonly */
146 #define F_MULTIFILE 2 /**< flag to tell us a file is exported using -m */
147 #define F_COPYONWRITE 4 /**< flag to tell us a file is exported using
149 #define F_AUTOREADONLY 8 /**< flag to tell us a file is set to autoreadonly */
150 #define F_SPARSE 16 /**< flag to tell us copyronwrite should use a sparse file */
151 #define F_SDP 32 /**< flag to tell us the export should be done using the Socket Direct Protocol for RDMA */
152 GHashTable *children;
153 char pidfname[256]; /**< name of our PID file */
154 char pidftemplate[256]; /**< template to be used for the filename of the PID file */
155 char default_authname[] = SYSCONFDIR "/nbd-server/allow"; /**< default name of allow file */
158 * Types of virtuatlization
161 VIRT_NONE=0, /**< No virtualization */
162 VIRT_IPLIT, /**< Literal IP address as part of the filename */
163 VIRT_IPHASH, /**< Replacing all dots in an ip address by a / before
164 doing the same as in IPLIT */
165 VIRT_CIDR, /**< Every subnet in its own directory */
169 * Variables associated with a server.
172 gchar* exportname; /**< (unprocessed) filename of the file we're exporting */
173 off_t expected_size; /**< size of the exported file as it was told to
174 us through configuration */
175 unsigned int port; /**< port we're exporting this file at */
176 char* authname; /**< filename of the authorization file */
177 int flags; /**< flags associated with this exported file */
178 unsigned int timeout;/**< how long a connection may be idle
180 int socket; /**< The socket of this server. */
181 VIRT_STYLE virtstyle;/**< The style of virtualization, if any */
182 uint8_t cidrlen; /**< The length of the mask when we use
183 CIDR-style virtualization */
184 gchar* prerun; /**< command to be ran after connecting a client,
185 but before starting to serve */
186 gchar* postrun; /**< command that will be ran after the client
191 * Variables associated with a client socket.
194 int fhandle; /**< file descriptor */
195 off_t startoff; /**< starting offset of this file */
199 off_t exportsize; /**< size of the file we're exporting */
200 char *clientname; /**< peer */
201 char *exportname; /**< (processed) filename of the file we're exporting */
202 GArray *export; /**< array of FILE_INFO of exported files;
203 array size is always 1 unless we're
204 doing the multiple file option */
205 int net; /**< The actual client socket */
206 SERVER *server; /**< The server this client is getting data from */
207 char* difffilename; /**< filename of the copy-on-write file, if any */
208 int difffile; /**< filedescriptor of copyonwrite file. @todo
209 shouldn't this be an array too? (cfr export) Or
210 make -m and -c mutually exclusive */
211 u32 difffilelen; /**< number of pages in difffile */
212 u32 *difmap; /**< see comment on the global difmap for this one */
216 * Type of configuration file values
219 PARAM_INT, /**< This parameter is an integer */
220 PARAM_STRING, /**< This parameter is a string */
221 PARAM_BOOL, /**< This parameter is a boolean */
225 * Configuration file values
228 gchar *paramname; /**< Name of the parameter, as it appears in
230 gboolean required; /**< Whether this is a required (as opposed to
231 optional) parameter */
232 PARAM_TYPE ptype; /**< Type of the parameter. */
233 gpointer target; /**< Pointer to where the data of this
234 parameter should be written. If ptype is
235 PARAM_BOOL, the data is or'ed rather than
237 gint flagval; /**< Flag mask for this parameter in case ptype
242 * Check whether a client is allowed to connect. Works with an authorization
243 * file which contains one line per machine, no wildcards.
245 * @param opts The client who's trying to connect.
246 * @return 0 - authorization refused, 1 - OK
248 int authorized_client(CLIENT *opts) {
249 const char *ERRMSG="Invalid entry '%s' in authfile '%s', so, refusing all connections.";
254 struct in_addr client;
255 struct in_addr cltemp;
258 if ((f=fopen(opts->server->authname,"r"))==NULL) {
259 msg4(LOG_INFO,"Can't open authorization file %s (%s).",
260 opts->server->authname,strerror(errno)) ;
264 inet_aton(opts->clientname, &client);
265 while (fgets(line,LINELEN,f)!=NULL) {
266 if((tmp=index(line, '/'))) {
267 if(strlen(line)<=tmp-line) {
268 msg4(LOG_CRIT, ERRMSG, line, opts->server->authname);
272 if(inet_aton(line,&addr)) {
273 msg4(LOG_CRIT, ERRMSG, line, opts->server->authname);
276 len=strtol(tmp, NULL, 0);
277 addr.s_addr>>=32-len;
278 addr.s_addr<<=32-len;
279 memcpy(&cltemp,&client,sizeof(client));
280 cltemp.s_addr>>=32-len;
281 cltemp.s_addr<<=32-len;
282 if(addr.s_addr == cltemp.s_addr) {
286 if (strncmp(line,opts->clientname,strlen(opts->clientname))==0) {
296 * Read data from a file descriptor into a buffer
298 * @param f a file descriptor
299 * @param buf a buffer
300 * @param len the number of bytes to be read
302 inline void readit(int f, void *buf, size_t len) {
306 if ((res = read(f, buf, len)) <= 0)
307 err("Read failed: %m");
314 * Write data from a buffer into a filedescriptor
316 * @param f a file descriptor
317 * @param buf a buffer containing data
318 * @param len the number of bytes to be written
320 inline void writeit(int f, void *buf, size_t len) {
324 if ((res = write(f, buf, len)) <= 0)
325 err("Send failed: %m");
332 * Print out a message about how to use nbd-server. Split out to a separate
333 * function so that we can call it from multiple places
336 printf("This is nbd-server version " VERSION "\n");
337 printf("Usage: port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-a timeout_sec] [-C configuration file] [-p PID file name] [-o section name]\n"
338 "\t-r|--read-only\t\tread only\n"
339 "\t-m|--multi-file\t\tmultiple file\n"
340 "\t-c|--copy-on-write\tcopy on write\n"
341 "\t-C|--config-file\tspecify an alternate configuration file\n"
342 "\t-l|--authorize-file\tfile with list of hosts that are allowed to\n\t\t\t\tconnect.\n"
343 "\t-a|--idle-time\t\tmaximum idle seconds; server terminates when\n\t\t\t\tidle time exceeded\n"
344 "\t-p|--pid-file\t\tspecify a filename to write our PID to\n"
345 "\t-o|--output-config\toutput a config file section for what you\n\t\t\t\tspecified on the command line, with the\n\t\t\t\tspecified section name\n\n"
346 "\tif port is set to 0, stdin is used (for running from inetd)\n"
347 "\tif file_to_export contains '%%s', it is substituted with the IP\n"
348 "\t\taddress of the machine trying to connect\n" );
349 printf("Using configuration file %s\n", CFILE);
352 /* Dumps a config file section of the given SERVER*, and exits. */
353 void dump_section(SERVER* serve, gchar* section_header) {
354 printf("[%s]\n", section_header);
355 printf("\texportname = %s\n", serve->exportname);
356 printf("\tport = %d\n", serve->port);
357 if(serve->flags & F_READONLY) {
358 printf("\treadonly = true\n");
360 if(serve->flags & F_MULTIFILE) {
361 printf("\tmultifile = true\n");
363 if(serve->flags & F_COPYONWRITE) {
364 printf("\tcopyonwrite = true\n");
366 if(serve->expected_size) {
367 printf("\tfilesize = %Ld\n", (long long int)serve->expected_size);
369 if(serve->authname) {
370 printf("\tauthfile = %s\n", serve->authname);
373 printf("\ttimeout = %d\n", serve->timeout);
379 * Parse the command line.
381 * @param argc the argc argument to main()
382 * @param argv the argv argument to main()
384 SERVER* cmdline(int argc, char *argv[]) {
388 struct option long_options[] = {
389 {"read-only", no_argument, NULL, 'r'},
390 {"multi-file", no_argument, NULL, 'm'},
391 {"copy-on-write", no_argument, NULL, 'c'},
392 {"authorize-file", required_argument, NULL, 'l'},
393 {"idle-time", required_argument, NULL, 'a'},
394 {"config-file", required_argument, NULL, 'C'},
395 {"pid-file", required_argument, NULL, 'p'},
396 {"output-config", required_argument, NULL, 'o'},
403 gboolean do_output=FALSE;
404 gchar* section_header;
409 serve=g_new0(SERVER, 1);
410 serve->authname = g_strdup(default_authname);
411 serve->virtstyle=VIRT_IPLIT;
412 while((c=getopt_long(argc, argv, "-a:C:cl:mo:rp:", long_options, &i))>=0) {
415 /* non-option argument */
416 switch(nonspecial++) {
418 serve->port=strtol(optarg, NULL, 0);
421 serve->exportname = g_strdup(optarg);
422 if(serve->exportname[0] != '/') {
423 fprintf(stderr, "E: The to be exported file needs to be an absolute filename!\n");
428 last=strlen(optarg)-1;
430 if (suffix == 'k' || suffix == 'K' ||
431 suffix == 'm' || suffix == 'M')
433 es = (off_t)atol(optarg);
441 serve->expected_size = es;
446 serve->flags |= F_READONLY;
449 serve->flags |= F_MULTIFILE;
453 section_header = g_strdup(optarg);
456 strncpy(pidftemplate, optarg, 256);
459 serve->flags |=F_COPYONWRITE;
462 g_free(config_file_pos);
463 config_file_pos=g_strdup(optarg);
466 g_free(serve->authname);
467 serve->authname=g_strdup(optarg);
470 serve->timeout=strtol(optarg, NULL, 0);
478 /* What's left: the port to export, the name of the to be exported
479 * file, and, optionally, the size of the file, in that order. */
486 g_critical("Need a complete configuration on the command line to output a config file section!");
489 dump_section(serve, section_header);
495 * Error codes for config file parsing
498 CFILE_NOTFOUND, /**< The configuration file is not found */
499 CFILE_MISSING_GENERIC, /**< The (required) group "generic" is missing */
500 CFILE_KEY_MISSING, /**< A (required) key is missing */
501 CFILE_VALUE_INVALID, /**< A value is syntactically invalid */
502 CFILE_VALUE_UNSUPPORTED,/**< A value is not supported in this build */
503 CFILE_PROGERR /**< Programmer error */
507 * Remove a SERVER from memory. Used from the hash table
509 void remove_server(gpointer s) {
513 g_free(server->exportname);
515 g_free(server->authname);
520 * Parse the config file.
522 * @param f the name of the config file
523 * @param e a GError. @see CFILE_ERRORS for what error values this function can
525 * @return a Array of SERVER* pointers, If the config file is empty or does not
526 * exist, returns an empty GHashTable; if the config file contains an
527 * error, returns NULL, and e is set appropriately
529 GArray* parse_cfile(gchar* f, GError** e) {
530 const char* DEFAULT_ERROR = "Could not parse %s in group %s: %s";
531 const char* MISSING_REQUIRED_ERROR = "Could not find required value %s in group %s: %s";
533 gchar *virtstyle=NULL;
535 { "exportname", TRUE, PARAM_STRING, NULL, 0 },
536 { "port", TRUE, PARAM_INT, NULL, 0 },
537 { "authfile", FALSE, PARAM_STRING, NULL, 0 },
538 { "timeout", FALSE, PARAM_INT, NULL, 0 },
539 { "filesize", FALSE, PARAM_INT, NULL, 0 },
540 { "virtstyle", FALSE, PARAM_STRING, NULL, 0 },
541 { "prerun", FALSE, PARAM_STRING, NULL, 0 },
542 { "postrun", FALSE, PARAM_STRING, NULL, 0 },
543 { "readonly", FALSE, PARAM_BOOL, NULL, F_READONLY },
544 { "multifile", FALSE, PARAM_BOOL, NULL, F_MULTIFILE },
545 { "copyonwrite", FALSE, PARAM_BOOL, NULL, F_COPYONWRITE },
546 { "autoreadonly", FALSE, PARAM_BOOL, NULL, F_AUTOREADONLY },
547 { "sparse_cow", FALSE, PARAM_BOOL, NULL, F_SPARSE },
548 { "sdp", FALSE, PARAM_BOOL, NULL, F_SDP },
550 const int lp_size=14;
552 { "user", FALSE, PARAM_STRING, &runuser, 0 },
553 { "group", FALSE, PARAM_STRING, &rungroup, 0 },
559 const char *err_msg=NULL;
567 errdomain = g_quark_from_string("parse_cfile");
568 cfile = g_key_file_new();
569 retval = g_array_new(FALSE, TRUE, sizeof(SERVER));
570 if(!g_key_file_load_from_file(cfile, f, G_KEY_FILE_KEEP_COMMENTS |
571 G_KEY_FILE_KEEP_TRANSLATIONS, &err)) {
572 g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.");
573 g_key_file_free(cfile);
576 if(strcmp(g_key_file_get_start_group(cfile), "generic")) {
577 g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
578 g_key_file_free(cfile);
581 groups = g_key_file_get_groups(cfile, NULL);
582 for(i=0;groups[i];i++) {
583 memset(&s, '\0', sizeof(SERVER));
584 lp[0].target=&(s.exportname);
585 lp[1].target=&(s.port);
586 lp[2].target=&(s.authname);
587 lp[3].target=&(s.timeout);
588 lp[4].target=&(s.expected_size);
589 lp[5].target=&(virtstyle);
590 lp[6].target=&(s.prerun);
591 lp[7].target=&(s.postrun);
592 lp[8].target=lp[9].target=lp[10].target=
593 lp[11].target=lp[12].target=
594 lp[13].target=&(s.flags);
596 /* After the [generic] group, start parsing exports */
601 for(j=0;j<p_size;j++) {
602 g_assert(p[j].target != NULL);
603 g_assert(p[j].ptype==PARAM_INT||p[j].ptype==PARAM_STRING||p[j].ptype==PARAM_BOOL);
606 *((gint*)p[j].target) =
607 g_key_file_get_integer(cfile,
613 *((gchar**)p[j].target) =
614 g_key_file_get_string(cfile,
620 value = g_key_file_get_boolean(cfile,
622 p[j].paramname, &err);
625 *((gint*)p[j].target) |= p[j].flagval;
627 *((gint*)p[j].target) &= ~(p[j].flagval);
633 if(err->code == G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
635 /* Ignore not-found error for optional values */
639 err_msg = MISSING_REQUIRED_ERROR;
642 err_msg = DEFAULT_ERROR;
644 g_set_error(e, errdomain, CFILE_VALUE_INVALID, err_msg, p[j].paramname, groups[i], err->message);
645 g_array_free(retval, TRUE);
647 g_key_file_free(cfile);
652 if(!strncmp(virtstyle, "none", 4)) {
653 s.virtstyle=VIRT_NONE;
654 } else if(!strncmp(virtstyle, "ipliteral", 9)) {
655 s.virtstyle=VIRT_IPLIT;
656 } else if(!strncmp(virtstyle, "iphash", 6)) {
657 s.virtstyle=VIRT_IPHASH;
658 } else if(!strncmp(virtstyle, "cidrhash", 8)) {
659 s.virtstyle=VIRT_CIDR;
660 if(strlen(virtstyle)<10) {
661 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s: missing length", virtstyle, groups[i]);
662 g_array_free(retval, TRUE);
663 g_key_file_free(cfile);
666 s.cidrlen=strtol(virtstyle+8, NULL, 0);
668 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s", virtstyle, groups[i]);
669 g_array_free(retval, TRUE);
670 g_key_file_free(cfile);
674 s.virtstyle=VIRT_IPLIT;
676 /* Don't need to free this, it's not our string */
678 /* Don't append values for the [generic] group */
680 g_array_append_val(retval, s);
683 if(s.flags & F_SDP) {
684 g_set_error(e, errdomain, CFILE_VALUE_UNSUPPORTED, "This nbd-server was built without support for SDP, yet group %s uses it", groups[i]);
685 g_array_free(retval, TRUE);
686 g_key_file_free(cfile);
695 * Signal handler for SIGCHLD
696 * @param s the signal we're handling (must be SIGCHLD, or something
699 void sigchld_handler(int s) {
704 while((pid=waitpid(-1, &status, WNOHANG)) > 0) {
705 if(WIFEXITED(status)) {
706 msg3(LOG_INFO, "Child exited with %d", WEXITSTATUS(status));
708 i=g_hash_table_lookup(children, &pid);
710 msg3(LOG_INFO, "SIGCHLD received for an unknown child with PID %ld", (long)pid);
712 DEBUG2("Removing %d from the list of children", pid);
713 g_hash_table_remove(children, &pid);
719 * Kill a child. Called from sigterm_handler::g_hash_table_foreach.
722 * @param value the value corresponding to the above key
723 * @param user_data a pointer which we always set to 1, so that we know what
726 void killchild(gpointer key, gpointer value, gpointer user_data) {
728 int *parent=user_data;
735 * Handle SIGTERM and dispatch it to our children
736 * @param s the signal we're handling (must be SIGTERM, or something
737 * is severely wrong).
739 void sigterm_handler(int s) {
742 g_hash_table_foreach(children, killchild, &parent);
752 * Detect the size of a file.
754 * @param fhandle An open filedescriptor
755 * @return the size of the file, or OFFT_MAX if detection was
758 off_t size_autodetect(int fhandle) {
760 unsigned long sectors;
761 struct stat stat_buf;
764 #ifdef HAVE_SYS_MOUNT_H
765 #ifdef HAVE_SYS_IOCTL_H
767 DEBUG("looking for export size with ioctl BLKGETSIZE\n");
768 if (!ioctl(fhandle, BLKGETSIZE, §ors) && sectors) {
769 es = (off_t)sectors * (off_t)512;
772 #endif /* BLKGETSIZE */
773 #endif /* HAVE_SYS_IOCTL_H */
774 #endif /* HAVE_SYS_MOUNT_H */
776 DEBUG("looking for fhandle size with fstat\n");
777 stat_buf.st_size = 0;
778 error = fstat(fhandle, &stat_buf);
780 if(stat_buf.st_size > 0)
781 return (off_t)stat_buf.st_size;
783 err("fstat failed: %m");
786 DEBUG("looking for fhandle size with lseek SEEK_END\n");
787 es = lseek(fhandle, (off_t)0, SEEK_END);
788 if (es > ((off_t)0)) {
791 DEBUG2("lseek failed: %d", errno==EBADF?1:(errno==ESPIPE?2:(errno==EINVAL?3:4)));
794 err("Could not find size of exported block device: %m");
799 * Get the file handle and offset, given an export offset.
801 * @param export An array of export files
802 * @param a The offset to get corresponding file/offset for
803 * @param fhandle [out] File descriptor
804 * @param foffset [out] Offset into fhandle
805 * @param maxbytes [out] Tells how many bytes can be read/written
806 * from fhandle starting at foffset (0 if there is no limit)
807 * @return 0 on success, -1 on failure
809 int get_filepos(GArray* export, off_t a, int* fhandle, off_t* foffset, size_t* maxbytes ) {
810 /* Negative offset not allowed */
814 /* Binary search for last file with starting offset <= a */
817 int end = export->len - 1;
818 while( start <= end ) {
819 int mid = (start + end) / 2;
820 fi = g_array_index(export, FILE_INFO, mid);
821 if( fi.startoff < a ) {
823 } else if( fi.startoff > a ) {
831 /* end should never go negative, since first startoff is 0 and a >= 0 */
834 fi = g_array_index(export, FILE_INFO, end);
835 *fhandle = fi.fhandle;
836 *foffset = a - fi.startoff;
838 if( end+1 < export->len ) {
839 FILE_INFO fi_next = g_array_index(export, FILE_INFO, end+1);
840 *maxbytes = fi_next.startoff - a;
847 * seek to a position in a file, with error handling.
848 * @param handle a filedescriptor
849 * @param a position to seek to
850 * @todo get rid of this; lastpoint is a global variable right now, but it
851 * shouldn't be. If we pass it on as a parameter, that makes things a *lot*
854 void myseek(int handle,off_t a) {
855 if (lseek(handle, a, SEEK_SET) < 0) {
856 err("Can not seek locally!\n");
861 * Write an amount of bytes at a given offset to the right file. This
862 * abstracts the write-side of the multiple file option.
864 * @param a The offset where the write should start
865 * @param buf The buffer to write from
866 * @param len The length of buf
867 * @param client The client we're serving for
868 * @return The number of bytes actually written, or -1 in case of an error
870 ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
875 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
877 if(maxbytes && len > maxbytes)
880 DEBUG4("(WRITE to fd %d offset %Lu len %u), ", fhandle, foffset, len);
882 myseek(fhandle, foffset);
883 return write(fhandle, buf, len);
887 * Call rawexpwrite repeatedly until all data has been written.
888 * @return 0 on success, nonzero on failure
890 int rawexpwrite_fully(off_t a, char *buf, size_t len, CLIENT *client) {
893 while(len > 0 && (ret=rawexpwrite(a, buf, len, client)) > 0 ) {
898 return (ret < 0 || len != 0);
902 * Read an amount of bytes at a given offset from the right file. This
903 * abstracts the read-side of the multiple files option.
905 * @param a The offset where the read should start
906 * @param buf A buffer to read into
907 * @param len The size of buf
908 * @param client The client we're serving for
909 * @return The number of bytes actually read, or -1 in case of an
912 ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
917 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
919 if(maxbytes && len > maxbytes)
922 DEBUG4("(READ from fd %d offset %Lu len %u), ", fhandle, foffset, len);
924 myseek(fhandle, foffset);
925 return read(fhandle, buf, len);
929 * Call rawexpread repeatedly until all data has been read.
930 * @return 0 on success, nonzero on failure
932 int rawexpread_fully(off_t a, char *buf, size_t len, CLIENT *client) {
935 while(len > 0 && (ret=rawexpread(a, buf, len, client)) > 0 ) {
940 return (ret < 0 || len != 0);
944 * Read an amount of bytes at a given offset from the right file. This
945 * abstracts the read-side of the copyonwrite stuff, and calls
946 * rawexpread() with the right parameters to do the actual work.
947 * @param a The offset where the read should start
948 * @param buf A buffer to read into
949 * @param len The size of buf
950 * @param client The client we're going to read for
951 * @return 0 on success, nonzero on failure
953 int expread(off_t a, char *buf, size_t len, CLIENT *client) {
955 off_t mapcnt, mapl, maph, pagestart;
957 if (!(client->server->flags & F_COPYONWRITE))
958 return(rawexpread_fully(a, buf, len, client));
959 DEBUG3("Asked to read %d bytes at %Lu.\n", len, (unsigned long long)a);
961 mapl=a/DIFFPAGESIZE; maph=(a+len-1)/DIFFPAGESIZE;
963 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
964 pagestart=mapcnt*DIFFPAGESIZE;
966 rdlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
967 len : (size_t)DIFFPAGESIZE-offset;
968 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
969 DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
970 (unsigned long)(client->difmap[mapcnt]));
971 myseek(client->difffile, client->difmap[mapcnt]*DIFFPAGESIZE+offset);
972 if (read(client->difffile, buf, rdlen) != rdlen) return -1;
973 } else { /* the block is not there */
974 DEBUG2("Page %Lu is not here, we read the original one\n",
975 (unsigned long long)mapcnt);
976 if(rawexpread_fully(a, buf, rdlen, client)) return -1;
978 len-=rdlen; a+=rdlen; buf+=rdlen;
984 * Write an amount of bytes at a given offset to the right file. This
985 * abstracts the write-side of the copyonwrite option, and calls
986 * rawexpwrite() with the right parameters to do the actual work.
988 * @param a The offset where the write should start
989 * @param buf The buffer to write from
990 * @param len The length of buf
991 * @param client The client we're going to write for.
992 * @return 0 on success, nonzero on failure
994 int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
995 char pagebuf[DIFFPAGESIZE];
996 off_t mapcnt,mapl,maph;
1001 if (!(client->server->flags & F_COPYONWRITE))
1002 return(rawexpwrite_fully(a, buf, len, client));
1003 DEBUG3("Asked to write %d bytes at %Lu.\n", len, (unsigned long long)a);
1005 mapl=a/DIFFPAGESIZE ; maph=(a+len-1)/DIFFPAGESIZE ;
1007 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
1008 pagestart=mapcnt*DIFFPAGESIZE ;
1009 offset=a-pagestart ;
1010 wrlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
1011 len : (size_t)DIFFPAGESIZE-offset;
1013 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
1014 DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
1015 (unsigned long)(client->difmap[mapcnt])) ;
1016 myseek(client->difffile,
1017 client->difmap[mapcnt]*DIFFPAGESIZE+offset);
1018 if (write(client->difffile, buf, wrlen) != wrlen) return -1 ;
1019 } else { /* the block is not there */
1020 myseek(client->difffile,client->difffilelen*DIFFPAGESIZE) ;
1021 client->difmap[mapcnt]=(client->server->flags&F_SPARSE)?mapcnt:client->difffilelen++;
1022 DEBUG3("Page %Lu is not here, we put it at %lu\n",
1023 (unsigned long long)mapcnt,
1024 (unsigned long)(client->difmap[mapcnt]));
1025 rdlen=DIFFPAGESIZE ;
1026 if (rawexpread_fully(pagestart, pagebuf, rdlen, client))
1028 memcpy(pagebuf+offset,buf,wrlen) ;
1029 if (write(client->difffile, pagebuf, DIFFPAGESIZE) !=
1033 len-=wrlen ; a+=wrlen ; buf+=wrlen ;
1039 * Do the initial negotiation.
1041 * @param client The client we're negotiating with.
1043 void negotiate(CLIENT *client) {
1046 u32 flags = NBD_FLAG_HAS_FLAGS;
1048 memset(zeros, '\0', sizeof(zeros));
1049 if (write(client->net, INIT_PASSWD, 8) < 0)
1050 err("Negotiation failed: %m");
1051 cliserv_magic = htonll(cliserv_magic);
1052 if (write(client->net, &cliserv_magic, sizeof(cliserv_magic)) < 0)
1053 err("Negotiation failed: %m");
1054 size_host = htonll((u64)(client->exportsize));
1055 if (write(client->net, &size_host, 8) < 0)
1056 err("Negotiation failed: %m");
1057 if (client->server->flags & F_READONLY)
1058 flags |= NBD_FLAG_READ_ONLY;
1059 flags = htonl(flags);
1060 if (write(client->net, &flags, 4) < 0)
1061 err("Negotiation failed: %m");
1062 if (write(client->net, zeros, 124) < 0)
1063 err("Negotiation failed: %m");
1066 /** sending macro. */
1067 #define SEND(net,reply) writeit( net, &reply, sizeof( reply ));
1069 #define ERROR(client,reply,errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
1071 * Serve a file to a single client.
1073 * @todo This beast needs to be split up in many tiny little manageable
1074 * pieces. Preferably with a chainsaw.
1076 * @param client The client we're going to serve to.
1077 * @return when the client disconnects
1079 int mainloop(CLIENT *client) {
1080 struct nbd_request request;
1081 struct nbd_reply reply;
1082 gboolean go_on=TRUE;
1087 DEBUG("Entering request loop!\n");
1088 reply.magic = htonl(NBD_REPLY_MAGIC);
1097 if (client->server->timeout)
1098 alarm(client->server->timeout);
1099 readit(client->net, &request, sizeof(request));
1100 request.from = ntohll(request.from);
1101 request.type = ntohl(request.type);
1103 if (request.type==NBD_CMD_DISC) {
1104 msg2(LOG_INFO, "Disconnect request received.");
1105 if (client->server->flags & F_COPYONWRITE) {
1106 if (client->difmap) g_free(client->difmap) ;
1107 close(client->difffile);
1108 unlink(client->difffilename);
1109 free(client->difffilename);
1115 len = ntohl(request.len);
1117 if (request.magic != htonl(NBD_REQUEST_MAGIC))
1118 err("Not enough magic.");
1119 if (len > BUFSIZE + sizeof(struct nbd_reply))
1120 err("Request too big!");
1122 printf("%s from %Lu (%Lu) len %d, ", request.type ? "WRITE" :
1123 "READ", (unsigned long long)request.from,
1124 (unsigned long long)request.from / 512, len);
1126 memcpy(reply.handle, request.handle, sizeof(reply.handle));
1127 if ((request.from + len) > (OFFT_MAX)) {
1128 DEBUG("[Number too large!]");
1129 ERROR(client, reply, EINVAL);
1133 if (((ssize_t)((off_t)request.from + len) > client->exportsize)) {
1135 ERROR(client, reply, EINVAL);
1139 if (request.type==NBD_CMD_WRITE) {
1140 DEBUG("wr: net->buf, ");
1141 readit(client->net, buf, len);
1142 DEBUG("buf->exp, ");
1143 if ((client->server->flags & F_READONLY) ||
1144 (client->server->flags & F_AUTOREADONLY)) {
1145 DEBUG("[WRITE to READONLY!]");
1146 ERROR(client, reply, EPERM);
1149 if (expwrite(request.from, buf, len, client)) {
1150 DEBUG("Write failed: %m" );
1151 ERROR(client, reply, errno);
1154 SEND(client->net, reply);
1160 DEBUG("exp->buf, ");
1161 if (expread(request.from, buf + sizeof(struct nbd_reply), len, client)) {
1162 DEBUG("Read failed: %m");
1163 ERROR(client, reply, errno);
1167 DEBUG("buf->net, ");
1168 memcpy(buf, &reply, sizeof(struct nbd_reply));
1169 writeit(client->net, buf, len + sizeof(struct nbd_reply));
1176 * Set up client export array, which is an array of FILE_INFO.
1177 * Also, split a single exportfile into multiple ones, if that was asked.
1178 * @param client information on the client which we want to setup export for
1180 void setupexport(CLIENT* client) {
1182 off_t laststartoff = 0, lastsize = 0;
1183 int multifile = (client->server->flags & F_MULTIFILE);
1185 client->export = g_array_new(TRUE, TRUE, sizeof(FILE_INFO));
1187 /* If multi-file, open as many files as we can.
1188 * If not, open exactly one file.
1189 * Calculate file sizes as we go to get total size. */
1193 mode_t mode = (client->server->flags & F_READONLY) ? O_RDONLY : O_RDWR;
1196 tmpname=g_strdup_printf("%s.%d", client->exportname, i);
1198 tmpname=g_strdup(client->exportname);
1200 DEBUG2( "Opening %s\n", tmpname );
1201 fi.fhandle = open(tmpname, mode);
1202 if(fi.fhandle == -1 && mode == O_RDWR) {
1203 /* Try again because maybe media was read-only */
1204 fi.fhandle = open(tmpname, O_RDONLY);
1205 if(fi.fhandle != -1) {
1206 client->server->flags |= F_AUTOREADONLY;
1207 client->server->flags |= F_READONLY;
1210 if(fi.fhandle == -1) {
1211 if(multifile && i>0)
1213 err("Could not open exported file: %m");
1215 fi.startoff = laststartoff + lastsize;
1216 g_array_append_val(client->export, fi);
1219 /* Starting offset and size of this file will be used to
1220 * calculate starting offset of next file */
1221 laststartoff = fi.startoff;
1222 lastsize = size_autodetect(fi.fhandle);
1228 /* Set export size to total calculated size */
1229 client->exportsize = laststartoff + lastsize;
1231 /* Export size may be overridden */
1232 if(client->server->expected_size) {
1233 /* desired size must be <= total calculated size */
1234 if(client->server->expected_size > client->exportsize) {
1235 err("Size of exported file is too big\n");
1238 client->exportsize = client->server->expected_size;
1241 msg3(LOG_INFO, "Size of exported file/device is %Lu", (unsigned long long)client->exportsize);
1243 msg3(LOG_INFO, "Total number of files: %d", i);
1247 int copyonwrite_prepare(CLIENT* client) {
1249 if ((client->difffilename = malloc(1024))==NULL)
1250 err("Failed to allocate string for diff file name");
1251 snprintf(client->difffilename, 1024, "%s-%s-%d.diff",client->exportname,client->clientname,
1253 client->difffilename[1023]='\0';
1254 msg3(LOG_INFO,"About to create map and diff file %s",client->difffilename) ;
1255 client->difffile=open(client->difffilename,O_RDWR | O_CREAT | O_TRUNC,0600) ;
1256 if (client->difffile<0) err("Could not create diff file (%m)") ;
1257 if ((client->difmap=calloc(client->exportsize/DIFFPAGESIZE,sizeof(u32)))==NULL)
1258 err("Could not allocate memory") ;
1259 for (i=0;i<client->exportsize/DIFFPAGESIZE;i++) client->difmap[i]=(u32)-1 ;
1265 * Run a command. This is used for the ``prerun'' and ``postrun'' config file
1268 * @param command the command to be ran. Read from the config file
1269 * @param file the file name we're about to export
1271 int do_run(gchar* command, gchar* file) {
1275 if(command && *command) {
1276 cmd = g_strdup_printf(command, file);
1284 * Serve a connection.
1286 * @todo allow for multithreading, perhaps use libevent. Not just yet, though;
1287 * follow the road map.
1289 * @param client a connected client
1291 void serveconnection(CLIENT *client) {
1292 if(do_run(client->server->prerun, client->exportname)) {
1295 setupexport(client);
1297 if (client->server->flags & F_COPYONWRITE) {
1298 copyonwrite_prepare(client);
1301 setmysockopt(client->net);
1304 do_run(client->server->postrun, client->exportname);
1308 * Find the name of the file we have to serve. This will use g_strdup_printf
1309 * to put the IP address of the client inside a filename containing
1310 * "%s" (in the form as specified by the "virtstyle" option). That name
1311 * is then written to client->exportname.
1313 * @param net A socket connected to an nbd client
1314 * @param client information about the client. The IP address in human-readable
1315 * format will be written to a new char* buffer, the address of which will be
1316 * stored in client->clientname.
1318 void set_peername(int net, CLIENT *client) {
1319 struct sockaddr_in addrin;
1320 struct sockaddr_in netaddr;
1321 size_t addrinlen = sizeof( addrin );
1327 if (getpeername(net, (struct sockaddr *) &addrin, (socklen_t *)&addrinlen) < 0)
1328 err("getsockname failed: %m");
1329 peername = g_strdup(inet_ntoa(addrin.sin_addr));
1330 switch(client->server->virtstyle) {
1332 client->exportname=g_strdup(client->server->exportname);
1335 for(i=0;i<strlen(peername);i++) {
1336 if(peername[i]=='.') {
1341 client->exportname=g_strdup_printf(client->server->exportname, peername);
1344 memcpy(&netaddr, &addrin, addrinlen);
1345 netaddr.sin_addr.s_addr>>=32-(client->server->cidrlen);
1346 netaddr.sin_addr.s_addr<<=32-(client->server->cidrlen);
1347 netname = inet_ntoa(netaddr.sin_addr);
1348 tmp=g_strdup_printf("%s/%s", netname, peername);
1349 client->exportname=g_strdup_printf(client->server->exportname, tmp);
1353 msg4(LOG_INFO, "connect from %s, assigned file is %s",
1354 peername, client->exportname);
1355 client->clientname=g_strdup(peername);
1361 * @param data a pointer to pid_t which should be freed
1363 void destroy_pid_t(gpointer data) {
1368 * Loop through the available servers, and serve them. Never returns.
1370 int serveloop(GArray* servers) G_GNUC_NORETURN {
1371 struct sockaddr_in addrin;
1372 socklen_t addrinlen=sizeof(addrin);
1382 * Set up the master fd_set. The set of descriptors we need
1383 * to select() for never changes anyway and it buys us a *lot*
1384 * of time to only build this once. However, if we ever choose
1385 * to not fork() for clients anymore, we may have to revisit
1390 for(i=0;i<servers->len;i++) {
1391 sock=(g_array_index(servers, SERVER, i)).socket;
1392 FD_SET(sock, &mset);
1393 max=sock>max?sock:max;
1400 memcpy(&rset, &mset, sizeof(fd_set));
1403 if(select(max+1, &rset, NULL, NULL, &tv)>0) {
1405 for(i=0;i<servers->len;i++) {
1406 serve=&(g_array_index(servers, SERVER, i));
1407 if(FD_ISSET(serve->socket, &rset)) {
1408 if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
1411 client = g_malloc(sizeof(CLIENT));
1412 client->server=serve;
1413 client->exportsize=OFFT_MAX;
1415 set_peername(net, client);
1416 if (!authorized_client(client)) {
1417 msg2(LOG_INFO,"Unauthorized client") ;
1421 msg2(LOG_INFO,"Authorized client") ;
1422 pid=g_malloc(sizeof(pid_t));
1424 if ((*pid=fork())<0) {
1425 msg3(LOG_INFO,"Could not fork (%s)",strerror(errno)) ;
1429 if (*pid>0) { /* parent */
1431 g_hash_table_insert(children, pid, pid);
1435 g_hash_table_destroy(children);
1436 for(i=0;i<servers->len;i++) {
1437 serve=g_array_index(servers, SERVER*, i);
1438 close(serve->socket);
1440 /* FALSE does not free the
1441 actual data. This is required,
1442 because the client has a
1443 direct reference into that
1444 data, and otherwise we get a
1446 g_array_free(servers, FALSE);
1448 msg2(LOG_INFO,"Starting to serve");
1449 serveconnection(client);
1458 * Go daemon (unless we specified at compile time that we didn't want this)
1459 * @param serve the first server of our configuration. If its port is zero,
1460 * then do not daemonize, because we're doing inetd then. This parameter
1461 * is only used to create a PID file of the form
1462 * /var/run/nbd-server.<port>.pid; it's not modified in any way.
1464 #if !defined(NODAEMON) && !defined(NOFORK)
1465 void daemonize(SERVER* serve) {
1468 if(serve && !(serve->port)) {
1474 if(!*pidftemplate) {
1476 strncpy(pidftemplate, "/var/run/server.%d.pid", 255);
1478 strncpy(pidftemplate, "/var/run/server.pid", 255);
1481 snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
1482 pidf=fopen(pidfname, "w");
1484 fprintf(pidf,"%d\n", (int)getpid());
1488 fprintf(stderr, "Not fatal; continuing");
1492 #define daemonize(serve)
1493 #endif /* !defined(NODAEMON) && !defined(NOFORK) */
1496 * Everything beyond this point (in the file) is run in non-daemon mode.
1497 * The stuff above daemonize() isn't.
1500 void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN {
1501 g_message("Export of %s on port %d failed:", serve->exportname,
1507 * Connect a server's socket.
1509 * @param serve the server we want to connect.
1511 void setup_serve(SERVER *serve) {
1512 struct sockaddr_in addrin;
1513 struct sigaction sa;
1514 int addrinlen = sizeof(addrin);
1525 if ((serve->flags) && F_SDP) {
1529 if ((serve->socket = socket(af, SOCK_STREAM, IPPROTO_TCP)) < 0)
1532 /* lose the pesky "Address already in use" error message */
1533 if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
1534 err("setsockopt SO_REUSEADDR");
1536 if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
1537 err("setsockopt SO_KEEPALIVE");
1540 /* make the listening socket non-blocking */
1541 if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
1542 err("fcntl F_GETFL");
1544 if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
1545 err("fcntl F_SETFL O_NONBLOCK");
1548 DEBUG("Waiting for connections... bind, ");
1549 addrin.sin_family = AF_INET;
1551 if(serve->flags & F_SDP) {
1552 addrin.sin_family = AF_INET_SDP;
1555 addrin.sin_port = htons(serve->port);
1556 addrin.sin_addr.s_addr = 0;
1557 if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
1560 if (listen(serve->socket, 1) < 0)
1562 sa.sa_handler = sigchld_handler;
1563 sigemptyset(&sa.sa_mask);
1564 sa.sa_flags = SA_RESTART;
1565 if(sigaction(SIGCHLD, &sa, NULL) == -1)
1566 err("sigaction: %m");
1567 sa.sa_handler = sigterm_handler;
1568 sigemptyset(&sa.sa_mask);
1569 sa.sa_flags = SA_RESTART;
1570 if(sigaction(SIGTERM, &sa, NULL) == -1)
1571 err("sigaction: %m");
1575 * Connect our servers.
1577 void setup_servers(GArray* servers) {
1580 for(i=0;i<servers->len;i++) {
1581 setup_serve(&(g_array_index(servers, SERVER, i)));
1583 children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
1587 * Set up user-ID and/or group-ID
1589 void dousers(void) {
1593 gr=getgrnam(rungroup);
1595 g_message("Invalid group name: %s", rungroup);
1598 if(setgid(gr->gr_gid)<0)
1599 msg3(LOG_DEBUG, "Could not set GID: %s", strerror(errno));
1602 pw=getpwnam(runuser);
1604 g_message("Invalid user name: %s", runuser);
1607 if(setuid(pw->pw_uid)<0)
1608 msg3(LOG_DEBUG, "Could not set UID: %s", strerror(errno));
1613 * Main entry point...
1615 int main(int argc, char *argv[]) {
1620 if (sizeof( struct nbd_request )!=28) {
1621 fprintf(stderr,"Bad size of structure. Alignment problems?\n");
1625 memset(pidftemplate, '\0', 256);
1628 config_file_pos = g_strdup(CFILE);
1629 serve=cmdline(argc, argv);
1630 servers = parse_cfile(config_file_pos, &err);
1631 if(!servers || !servers->len) {
1632 g_warning("Could not parse config file: %s",
1633 err ? err->message : "Unknown error");
1636 g_array_append_val(servers, *serve);
1638 if (!(serve->port)) {
1641 /* You really should define ISSERVER if you're going to use
1642 * inetd mode, but if you don't, closing stdout and stderr
1643 * (which inetd had connected to the client socket) will let it
1647 open("/dev/null", O_WRONLY);
1648 open("/dev/null", O_WRONLY);
1650 client=g_malloc(sizeof(CLIENT));
1651 client->server=serve;
1653 client->exportsize=OFFT_MAX;
1654 set_peername(0,client);
1655 serveconnection(client);
1659 if((!serve) && (!servers||!servers->len)) {
1660 g_message("Nothing to do! Bye!");
1664 setup_servers(servers);