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 gchar* listenaddr; /**< The IP address we're listening on */
176 unsigned int port; /**< port we're exporting this file at */
177 char* authname; /**< filename of the authorization file */
178 int flags; /**< flags associated with this exported file */
179 unsigned int timeout;/**< how long a connection may be idle
181 int socket; /**< The socket of this server. */
182 VIRT_STYLE virtstyle;/**< The style of virtualization, if any */
183 uint8_t cidrlen; /**< The length of the mask when we use
184 CIDR-style virtualization */
185 gchar* prerun; /**< command to be ran after connecting a client,
186 but before starting to serve */
187 gchar* postrun; /**< command that will be ran after the client
192 * Variables associated with a client socket.
195 int fhandle; /**< file descriptor */
196 off_t startoff; /**< starting offset of this file */
200 off_t exportsize; /**< size of the file we're exporting */
201 char *clientname; /**< peer */
202 char *exportname; /**< (processed) filename of the file we're exporting */
203 GArray *export; /**< array of FILE_INFO of exported files;
204 array size is always 1 unless we're
205 doing the multiple file option */
206 int net; /**< The actual client socket */
207 SERVER *server; /**< The server this client is getting data from */
208 char* difffilename; /**< filename of the copy-on-write file, if any */
209 int difffile; /**< filedescriptor of copyonwrite file. @todo
210 shouldn't this be an array too? (cfr export) Or
211 make -m and -c mutually exclusive */
212 u32 difffilelen; /**< number of pages in difffile */
213 u32 *difmap; /**< see comment on the global difmap for this one */
217 * Type of configuration file values
220 PARAM_INT, /**< This parameter is an integer */
221 PARAM_STRING, /**< This parameter is a string */
222 PARAM_BOOL, /**< This parameter is a boolean */
226 * Configuration file values
229 gchar *paramname; /**< Name of the parameter, as it appears in
231 gboolean required; /**< Whether this is a required (as opposed to
232 optional) parameter */
233 PARAM_TYPE ptype; /**< Type of the parameter. */
234 gpointer target; /**< Pointer to where the data of this
235 parameter should be written. If ptype is
236 PARAM_BOOL, the data is or'ed rather than
238 gint flagval; /**< Flag mask for this parameter in case ptype
243 * Check whether a client is allowed to connect. Works with an authorization
244 * file which contains one line per machine, no wildcards.
246 * @param opts The client who's trying to connect.
247 * @return 0 - authorization refused, 1 - OK
249 int authorized_client(CLIENT *opts) {
250 const char *ERRMSG="Invalid entry '%s' in authfile '%s', so, refusing all connections.";
255 struct in_addr client;
256 struct in_addr cltemp;
259 if ((f=fopen(opts->server->authname,"r"))==NULL) {
260 msg4(LOG_INFO,"Can't open authorization file %s (%s).",
261 opts->server->authname,strerror(errno)) ;
265 inet_aton(opts->clientname, &client);
266 while (fgets(line,LINELEN,f)!=NULL) {
267 if((tmp=index(line, '/'))) {
268 if(strlen(line)<=tmp-line) {
269 msg4(LOG_CRIT, ERRMSG, line, opts->server->authname);
273 if(inet_aton(line,&addr)) {
274 msg4(LOG_CRIT, ERRMSG, line, opts->server->authname);
277 len=strtol(tmp, NULL, 0);
278 addr.s_addr>>=32-len;
279 addr.s_addr<<=32-len;
280 memcpy(&cltemp,&client,sizeof(client));
281 cltemp.s_addr>>=32-len;
282 cltemp.s_addr<<=32-len;
283 if(addr.s_addr == cltemp.s_addr) {
287 if (strncmp(line,opts->clientname,strlen(opts->clientname))==0) {
297 * Read data from a file descriptor into a buffer
299 * @param f a file descriptor
300 * @param buf a buffer
301 * @param len the number of bytes to be read
303 inline void readit(int f, void *buf, size_t len) {
307 if ((res = read(f, buf, len)) <= 0)
308 err("Read failed: %m");
315 * Write data from a buffer into a filedescriptor
317 * @param f a file descriptor
318 * @param buf a buffer containing data
319 * @param len the number of bytes to be written
321 inline void writeit(int f, void *buf, size_t len) {
325 if ((res = write(f, buf, len)) <= 0)
326 err("Send failed: %m");
333 * Print out a message about how to use nbd-server. Split out to a separate
334 * function so that we can call it from multiple places
337 printf("This is nbd-server version " VERSION "\n");
338 printf("Usage: [ip:]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"
339 "\t-r|--read-only\t\tread only\n"
340 "\t-m|--multi-file\t\tmultiple file\n"
341 "\t-c|--copy-on-write\tcopy on write\n"
342 "\t-C|--config-file\tspecify an alternate configuration file\n"
343 "\t-l|--authorize-file\tfile with list of hosts that are allowed to\n\t\t\t\tconnect.\n"
344 "\t-a|--idle-time\t\tmaximum idle seconds; server terminates when\n\t\t\t\tidle time exceeded\n"
345 "\t-p|--pid-file\t\tspecify a filename to write our PID to\n"
346 "\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"
347 "\tif port is set to 0, stdin is used (for running from inetd)\n"
348 "\tif file_to_export contains '%%s', it is substituted with the IP\n"
349 "\t\taddress of the machine trying to connect\n"
350 "\tif ip is set, it contains the local IP address on which we're listening.\n\tif not, the server will listen on all local IP addresses\n");
351 printf("Using configuration file %s\n", CFILE);
354 /* Dumps a config file section of the given SERVER*, and exits. */
355 void dump_section(SERVER* serve, gchar* section_header) {
356 printf("[%s]\n", section_header);
357 printf("\texportname = %s\n", serve->exportname);
358 printf("\tlistenaddr = %s\n", serve->listenaddr);
359 printf("\tport = %d\n", serve->port);
360 if(serve->flags & F_READONLY) {
361 printf("\treadonly = true\n");
363 if(serve->flags & F_MULTIFILE) {
364 printf("\tmultifile = true\n");
366 if(serve->flags & F_COPYONWRITE) {
367 printf("\tcopyonwrite = true\n");
369 if(serve->expected_size) {
370 printf("\tfilesize = %lld\n", (long long int)serve->expected_size);
372 if(serve->authname) {
373 printf("\tauthfile = %s\n", serve->authname);
376 printf("\ttimeout = %d\n", serve->timeout);
382 * Parse the command line.
384 * @param argc the argc argument to main()
385 * @param argv the argv argument to main()
387 SERVER* cmdline(int argc, char *argv[]) {
391 struct option long_options[] = {
392 {"read-only", no_argument, NULL, 'r'},
393 {"multi-file", no_argument, NULL, 'm'},
394 {"copy-on-write", no_argument, NULL, 'c'},
395 {"authorize-file", required_argument, NULL, 'l'},
396 {"idle-time", required_argument, NULL, 'a'},
397 {"config-file", required_argument, NULL, 'C'},
398 {"pid-file", required_argument, NULL, 'p'},
399 {"output-config", required_argument, NULL, 'o'},
406 gboolean do_output=FALSE;
407 gchar* section_header="";
413 serve=g_new0(SERVER, 1);
414 serve->authname = g_strdup(default_authname);
415 serve->virtstyle=VIRT_IPLIT;
416 while((c=getopt_long(argc, argv, "-a:C:cl:mo:rp:", long_options, &i))>=0) {
419 /* non-option argument */
420 switch(nonspecial++) {
422 addr_port=g_strsplit(optarg, ":", 2);
424 serve->port=strtol(addr_port[1], NULL, 0);
425 serve->listenaddr=g_strdup(addr_port[0]);
427 serve->listenaddr=g_strdup("0.0.0.0");
428 serve->port=strtol(addr_port[0], NULL, 0);
430 g_strfreev(addr_port);
433 serve->exportname = g_strdup(optarg);
434 if(serve->exportname[0] != '/') {
435 fprintf(stderr, "E: The to be exported file needs to be an absolute filename!\n");
440 last=strlen(optarg)-1;
442 if (suffix == 'k' || suffix == 'K' ||
443 suffix == 'm' || suffix == 'M')
445 es = (off_t)atoll(optarg);
453 serve->expected_size = es;
458 serve->flags |= F_READONLY;
461 serve->flags |= F_MULTIFILE;
465 section_header = g_strdup(optarg);
468 strncpy(pidftemplate, optarg, 256);
471 serve->flags |=F_COPYONWRITE;
474 g_free(config_file_pos);
475 config_file_pos=g_strdup(optarg);
478 g_free(serve->authname);
479 serve->authname=g_strdup(optarg);
482 serve->timeout=strtol(optarg, NULL, 0);
490 /* What's left: the port to export, the name of the to be exported
491 * file, and, optionally, the size of the file, in that order. */
498 g_critical("Need a complete configuration on the command line to output a config file section!");
501 dump_section(serve, section_header);
507 * Error codes for config file parsing
510 CFILE_NOTFOUND, /**< The configuration file is not found */
511 CFILE_MISSING_GENERIC, /**< The (required) group "generic" is missing */
512 CFILE_KEY_MISSING, /**< A (required) key is missing */
513 CFILE_VALUE_INVALID, /**< A value is syntactically invalid */
514 CFILE_VALUE_UNSUPPORTED,/**< A value is not supported in this build */
515 CFILE_PROGERR, /**< Programmer error */
516 CFILE_NO_EXPORTS /**< A config file was specified that does not
517 define any exports */
521 * Remove a SERVER from memory. Used from the hash table
523 void remove_server(gpointer s) {
527 g_free(server->exportname);
529 g_free(server->authname);
534 * Parse the config file.
536 * @param f the name of the config file
537 * @param e a GError. @see CFILE_ERRORS for what error values this function can
539 * @return a Array of SERVER* pointers, If the config file is empty or does not
540 * exist, returns an empty GHashTable; if the config file contains an
541 * error, returns NULL, and e is set appropriately
543 GArray* parse_cfile(gchar* f, GError** e) {
544 const char* DEFAULT_ERROR = "Could not parse %s in group %s: %s";
545 const char* MISSING_REQUIRED_ERROR = "Could not find required value %s in group %s: %s";
547 gchar *virtstyle=NULL;
549 { "exportname", TRUE, PARAM_STRING, NULL, 0 },
550 { "port", TRUE, PARAM_INT, NULL, 0 },
551 { "authfile", FALSE, PARAM_STRING, NULL, 0 },
552 { "timeout", FALSE, PARAM_INT, NULL, 0 },
553 { "filesize", FALSE, PARAM_INT, NULL, 0 },
554 { "virtstyle", FALSE, PARAM_STRING, NULL, 0 },
555 { "prerun", FALSE, PARAM_STRING, NULL, 0 },
556 { "postrun", FALSE, PARAM_STRING, NULL, 0 },
557 { "readonly", FALSE, PARAM_BOOL, NULL, F_READONLY },
558 { "multifile", FALSE, PARAM_BOOL, NULL, F_MULTIFILE },
559 { "copyonwrite", FALSE, PARAM_BOOL, NULL, F_COPYONWRITE },
560 { "sparse_cow", FALSE, PARAM_BOOL, NULL, F_SPARSE },
561 { "sdp", FALSE, PARAM_BOOL, NULL, F_SDP },
562 { "listenaddr", FALSE, PARAM_STRING, NULL, 0 },
564 const int lp_size=sizeof(lp)/sizeof(PARAM);
566 { "user", FALSE, PARAM_STRING, &runuser, 0 },
567 { "group", FALSE, PARAM_STRING, &rungroup, 0 },
570 int p_size=sizeof(gp)/sizeof(PARAM);
573 const char *err_msg=NULL;
582 errdomain = g_quark_from_string("parse_cfile");
583 cfile = g_key_file_new();
584 retval = g_array_new(FALSE, TRUE, sizeof(SERVER));
585 if(!g_key_file_load_from_file(cfile, f, G_KEY_FILE_KEEP_COMMENTS |
586 G_KEY_FILE_KEEP_TRANSLATIONS, &err)) {
587 g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.");
588 g_key_file_free(cfile);
591 startgroup = g_key_file_get_start_group(cfile);
592 if(!startgroup || strcmp(startgroup, "generic")) {
593 g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
594 g_key_file_free(cfile);
597 groups = g_key_file_get_groups(cfile, NULL);
598 for(i=0;groups[i];i++) {
599 memset(&s, '\0', sizeof(SERVER));
600 lp[0].target=&(s.exportname);
601 lp[1].target=&(s.port);
602 lp[2].target=&(s.authname);
603 lp[3].target=&(s.timeout);
604 lp[4].target=&(s.expected_size);
605 lp[5].target=&(virtstyle);
606 lp[6].target=&(s.prerun);
607 lp[7].target=&(s.postrun);
608 lp[8].target=lp[9].target=lp[10].target=
609 lp[11].target=lp[12].target=&(s.flags);
610 lp[13].target=&(s.listenaddr);
612 /* After the [generic] group, start parsing exports */
617 for(j=0;j<p_size;j++) {
618 g_assert(p[j].target != NULL);
619 g_assert(p[j].ptype==PARAM_INT||p[j].ptype==PARAM_STRING||p[j].ptype==PARAM_BOOL);
622 *((gint*)p[j].target) =
623 g_key_file_get_integer(cfile,
629 *((gchar**)p[j].target) =
630 g_key_file_get_string(cfile,
636 value = g_key_file_get_boolean(cfile,
638 p[j].paramname, &err);
641 *((gint*)p[j].target) |= p[j].flagval;
643 *((gint*)p[j].target) &= ~(p[j].flagval);
649 if(err->code == G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
651 /* Ignore not-found error for optional values */
655 err_msg = MISSING_REQUIRED_ERROR;
658 err_msg = DEFAULT_ERROR;
660 g_set_error(e, errdomain, CFILE_VALUE_INVALID, err_msg, p[j].paramname, groups[i], err->message);
661 g_array_free(retval, TRUE);
663 g_key_file_free(cfile);
668 if(!strncmp(virtstyle, "none", 4)) {
669 s.virtstyle=VIRT_NONE;
670 } else if(!strncmp(virtstyle, "ipliteral", 9)) {
671 s.virtstyle=VIRT_IPLIT;
672 } else if(!strncmp(virtstyle, "iphash", 6)) {
673 s.virtstyle=VIRT_IPHASH;
674 } else if(!strncmp(virtstyle, "cidrhash", 8)) {
675 s.virtstyle=VIRT_CIDR;
676 if(strlen(virtstyle)<10) {
677 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s: missing length", virtstyle, groups[i]);
678 g_array_free(retval, TRUE);
679 g_key_file_free(cfile);
682 s.cidrlen=strtol(virtstyle+8, NULL, 0);
684 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s", virtstyle, groups[i]);
685 g_array_free(retval, TRUE);
686 g_key_file_free(cfile);
690 s.virtstyle=VIRT_IPLIT;
692 /* Don't need to free this, it's not our string */
694 /* Don't append values for the [generic] group */
697 s.listenaddr = g_strdup("0.0.0.0");
699 g_array_append_val(retval, s);
702 if(s.flags & F_SDP) {
703 g_set_error(e, errdomain, CFILE_VALUE_UNSUPPORTED, "This nbd-server was built without support for SDP, yet group %s uses it", groups[i]);
704 g_array_free(retval, TRUE);
705 g_key_file_free(cfile);
711 g_set_error(e, errdomain, CFILE_NO_EXPORTS, "The config file does not specify any exports");
713 g_key_file_free(cfile);
718 * Signal handler for SIGCHLD
719 * @param s the signal we're handling (must be SIGCHLD, or something
722 void sigchld_handler(int s) {
727 while((pid=waitpid(-1, &status, WNOHANG)) > 0) {
728 if(WIFEXITED(status)) {
729 msg3(LOG_INFO, "Child exited with %d", WEXITSTATUS(status));
731 i=g_hash_table_lookup(children, &pid);
733 msg3(LOG_INFO, "SIGCHLD received for an unknown child with PID %ld", (long)pid);
735 DEBUG2("Removing %d from the list of children", pid);
736 g_hash_table_remove(children, &pid);
742 * Kill a child. Called from sigterm_handler::g_hash_table_foreach.
745 * @param value the value corresponding to the above key
746 * @param user_data a pointer which we always set to 1, so that we know what
749 void killchild(gpointer key, gpointer value, gpointer user_data) {
751 int *parent=user_data;
758 * Handle SIGTERM and dispatch it to our children
759 * @param s the signal we're handling (must be SIGTERM, or something
760 * is severely wrong).
762 void sigterm_handler(int s) {
765 g_hash_table_foreach(children, killchild, &parent);
775 * Detect the size of a file.
777 * @param fhandle An open filedescriptor
778 * @return the size of the file, or OFFT_MAX if detection was
781 off_t size_autodetect(int fhandle) {
783 unsigned long sectors;
784 struct stat stat_buf;
787 #ifdef HAVE_SYS_MOUNT_H
788 #ifdef HAVE_SYS_IOCTL_H
790 DEBUG("looking for export size with ioctl BLKGETSIZE\n");
791 if (!ioctl(fhandle, BLKGETSIZE, §ors) && sectors) {
792 es = (off_t)sectors * (off_t)512;
795 #endif /* BLKGETSIZE */
796 #endif /* HAVE_SYS_IOCTL_H */
797 #endif /* HAVE_SYS_MOUNT_H */
799 DEBUG("looking for fhandle size with fstat\n");
800 stat_buf.st_size = 0;
801 error = fstat(fhandle, &stat_buf);
803 if(stat_buf.st_size > 0)
804 return (off_t)stat_buf.st_size;
806 err("fstat failed: %m");
809 DEBUG("looking for fhandle size with lseek SEEK_END\n");
810 es = lseek(fhandle, (off_t)0, SEEK_END);
811 if (es > ((off_t)0)) {
814 DEBUG2("lseek failed: %d", errno==EBADF?1:(errno==ESPIPE?2:(errno==EINVAL?3:4)));
817 err("Could not find size of exported block device: %m");
822 * Get the file handle and offset, given an export offset.
824 * @param export An array of export files
825 * @param a The offset to get corresponding file/offset for
826 * @param fhandle [out] File descriptor
827 * @param foffset [out] Offset into fhandle
828 * @param maxbytes [out] Tells how many bytes can be read/written
829 * from fhandle starting at foffset (0 if there is no limit)
830 * @return 0 on success, -1 on failure
832 int get_filepos(GArray* export, off_t a, int* fhandle, off_t* foffset, size_t* maxbytes ) {
833 /* Negative offset not allowed */
837 /* Binary search for last file with starting offset <= a */
840 int end = export->len - 1;
841 while( start <= end ) {
842 int mid = (start + end) / 2;
843 fi = g_array_index(export, FILE_INFO, mid);
844 if( fi.startoff < a ) {
846 } else if( fi.startoff > a ) {
854 /* end should never go negative, since first startoff is 0 and a >= 0 */
857 fi = g_array_index(export, FILE_INFO, end);
858 *fhandle = fi.fhandle;
859 *foffset = a - fi.startoff;
861 if( end+1 < export->len ) {
862 FILE_INFO fi_next = g_array_index(export, FILE_INFO, end+1);
863 *maxbytes = fi_next.startoff - a;
870 * seek to a position in a file, with error handling.
871 * @param handle a filedescriptor
872 * @param a position to seek to
873 * @todo get rid of this; lastpoint is a global variable right now, but it
874 * shouldn't be. If we pass it on as a parameter, that makes things a *lot*
877 void myseek(int handle,off_t a) {
878 if (lseek(handle, a, SEEK_SET) < 0) {
879 err("Can not seek locally!\n");
884 * Write an amount of bytes at a given offset to the right file. This
885 * abstracts the write-side of the multiple file option.
887 * @param a The offset where the write should start
888 * @param buf The buffer to write from
889 * @param len The length of buf
890 * @param client The client we're serving for
891 * @return The number of bytes actually written, or -1 in case of an error
893 ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
898 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
900 if(maxbytes && len > maxbytes)
903 DEBUG4("(WRITE to fd %d offset %llu len %u), ", fhandle, foffset, len);
905 myseek(fhandle, foffset);
906 return write(fhandle, buf, len);
910 * Call rawexpwrite repeatedly until all data has been written.
911 * @return 0 on success, nonzero on failure
913 int rawexpwrite_fully(off_t a, char *buf, size_t len, CLIENT *client) {
916 while(len > 0 && (ret=rawexpwrite(a, buf, len, client)) > 0 ) {
921 return (ret < 0 || len != 0);
925 * Read an amount of bytes at a given offset from the right file. This
926 * abstracts the read-side of the multiple files option.
928 * @param a The offset where the read should start
929 * @param buf A buffer to read into
930 * @param len The size of buf
931 * @param client The client we're serving for
932 * @return The number of bytes actually read, or -1 in case of an
935 ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
940 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
942 if(maxbytes && len > maxbytes)
945 DEBUG4("(READ from fd %d offset %llu len %u), ", fhandle, foffset, len);
947 myseek(fhandle, foffset);
948 return read(fhandle, buf, len);
952 * Call rawexpread repeatedly until all data has been read.
953 * @return 0 on success, nonzero on failure
955 int rawexpread_fully(off_t a, char *buf, size_t len, CLIENT *client) {
958 while(len > 0 && (ret=rawexpread(a, buf, len, client)) > 0 ) {
963 return (ret < 0 || len != 0);
967 * Read an amount of bytes at a given offset from the right file. This
968 * abstracts the read-side of the copyonwrite stuff, and calls
969 * rawexpread() with the right parameters to do the actual work.
970 * @param a The offset where the read should start
971 * @param buf A buffer to read into
972 * @param len The size of buf
973 * @param client The client we're going to read for
974 * @return 0 on success, nonzero on failure
976 int expread(off_t a, char *buf, size_t len, CLIENT *client) {
978 off_t mapcnt, mapl, maph, pagestart;
980 if (!(client->server->flags & F_COPYONWRITE))
981 return(rawexpread_fully(a, buf, len, client));
982 DEBUG3("Asked to read %d bytes at %llu.\n", len, (unsigned long long)a);
984 mapl=a/DIFFPAGESIZE; maph=(a+len-1)/DIFFPAGESIZE;
986 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
987 pagestart=mapcnt*DIFFPAGESIZE;
989 rdlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
990 len : (size_t)DIFFPAGESIZE-offset;
991 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
992 DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
993 (unsigned long)(client->difmap[mapcnt]));
994 myseek(client->difffile, client->difmap[mapcnt]*DIFFPAGESIZE+offset);
995 if (read(client->difffile, buf, rdlen) != rdlen) return -1;
996 } else { /* the block is not there */
997 DEBUG2("Page %llu is not here, we read the original one\n",
998 (unsigned long long)mapcnt);
999 if(rawexpread_fully(a, buf, rdlen, client)) return -1;
1001 len-=rdlen; a+=rdlen; buf+=rdlen;
1007 * Write an amount of bytes at a given offset to the right file. This
1008 * abstracts the write-side of the copyonwrite option, and calls
1009 * rawexpwrite() with the right parameters to do the actual work.
1011 * @param a The offset where the write should start
1012 * @param buf The buffer to write from
1013 * @param len The length of buf
1014 * @param client The client we're going to write for.
1015 * @return 0 on success, nonzero on failure
1017 int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
1018 char pagebuf[DIFFPAGESIZE];
1019 off_t mapcnt,mapl,maph;
1024 if (!(client->server->flags & F_COPYONWRITE))
1025 return(rawexpwrite_fully(a, buf, len, client));
1026 DEBUG3("Asked to write %d bytes at %llu.\n", len, (unsigned long long)a);
1028 mapl=a/DIFFPAGESIZE ; maph=(a+len-1)/DIFFPAGESIZE ;
1030 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
1031 pagestart=mapcnt*DIFFPAGESIZE ;
1032 offset=a-pagestart ;
1033 wrlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
1034 len : (size_t)DIFFPAGESIZE-offset;
1036 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
1037 DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
1038 (unsigned long)(client->difmap[mapcnt])) ;
1039 myseek(client->difffile,
1040 client->difmap[mapcnt]*DIFFPAGESIZE+offset);
1041 if (write(client->difffile, buf, wrlen) != wrlen) return -1 ;
1042 } else { /* the block is not there */
1043 myseek(client->difffile,client->difffilelen*DIFFPAGESIZE) ;
1044 client->difmap[mapcnt]=(client->server->flags&F_SPARSE)?mapcnt:client->difffilelen++;
1045 DEBUG3("Page %llu is not here, we put it at %lu\n",
1046 (unsigned long long)mapcnt,
1047 (unsigned long)(client->difmap[mapcnt]));
1048 rdlen=DIFFPAGESIZE ;
1049 if (rawexpread_fully(pagestart, pagebuf, rdlen, client))
1051 memcpy(pagebuf+offset,buf,wrlen) ;
1052 if (write(client->difffile, pagebuf, DIFFPAGESIZE) !=
1056 len-=wrlen ; a+=wrlen ; buf+=wrlen ;
1062 * Do the initial negotiation.
1064 * @param client The client we're negotiating with.
1066 void negotiate(CLIENT *client) {
1069 u32 flags = NBD_FLAG_HAS_FLAGS;
1071 memset(zeros, '\0', sizeof(zeros));
1072 if (write(client->net, INIT_PASSWD, 8) < 0)
1073 err("Negotiation failed: %m");
1074 cliserv_magic = htonll(cliserv_magic);
1075 if (write(client->net, &cliserv_magic, sizeof(cliserv_magic)) < 0)
1076 err("Negotiation failed: %m");
1077 size_host = htonll((u64)(client->exportsize));
1078 if (write(client->net, &size_host, 8) < 0)
1079 err("Negotiation failed: %m");
1080 if (client->server->flags & F_READONLY)
1081 flags |= NBD_FLAG_READ_ONLY;
1082 flags = htonl(flags);
1083 if (write(client->net, &flags, 4) < 0)
1084 err("Negotiation failed: %m");
1085 if (write(client->net, zeros, 124) < 0)
1086 err("Negotiation failed: %m");
1089 /** sending macro. */
1090 #define SEND(net,reply) writeit( net, &reply, sizeof( reply ));
1092 #define ERROR(client,reply,errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
1094 * Serve a file to a single client.
1096 * @todo This beast needs to be split up in many tiny little manageable
1097 * pieces. Preferably with a chainsaw.
1099 * @param client The client we're going to serve to.
1100 * @return when the client disconnects
1102 int mainloop(CLIENT *client) {
1103 struct nbd_request request;
1104 struct nbd_reply reply;
1105 gboolean go_on=TRUE;
1110 DEBUG("Entering request loop!\n");
1111 reply.magic = htonl(NBD_REPLY_MAGIC);
1120 if (client->server->timeout)
1121 alarm(client->server->timeout);
1122 readit(client->net, &request, sizeof(request));
1123 request.from = ntohll(request.from);
1124 request.type = ntohl(request.type);
1126 if (request.type==NBD_CMD_DISC) {
1127 msg2(LOG_INFO, "Disconnect request received.");
1128 if (client->server->flags & F_COPYONWRITE) {
1129 if (client->difmap) g_free(client->difmap) ;
1130 close(client->difffile);
1131 unlink(client->difffilename);
1132 free(client->difffilename);
1138 len = ntohl(request.len);
1140 if (request.magic != htonl(NBD_REQUEST_MAGIC))
1141 err("Not enough magic.");
1142 if (len > BUFSIZE + sizeof(struct nbd_reply))
1143 err("Request too big!");
1145 printf("%s from %llu (%llu) len %d, ", request.type ? "WRITE" :
1146 "READ", (unsigned long long)request.from,
1147 (unsigned long long)request.from / 512, len);
1149 memcpy(reply.handle, request.handle, sizeof(reply.handle));
1150 if ((request.from + len) > (OFFT_MAX)) {
1151 DEBUG("[Number too large!]");
1152 ERROR(client, reply, EINVAL);
1156 if (((ssize_t)((off_t)request.from + len) > client->exportsize)) {
1158 ERROR(client, reply, EINVAL);
1162 if (request.type==NBD_CMD_WRITE) {
1163 DEBUG("wr: net->buf, ");
1164 readit(client->net, buf, len);
1165 DEBUG("buf->exp, ");
1166 if ((client->server->flags & F_READONLY) ||
1167 (client->server->flags & F_AUTOREADONLY)) {
1168 DEBUG("[WRITE to READONLY!]");
1169 ERROR(client, reply, EPERM);
1172 if (expwrite(request.from, buf, len, client)) {
1173 DEBUG("Write failed: %m" );
1174 ERROR(client, reply, errno);
1177 SEND(client->net, reply);
1183 DEBUG("exp->buf, ");
1184 if (expread(request.from, buf + sizeof(struct nbd_reply), len, client)) {
1185 DEBUG("Read failed: %m");
1186 ERROR(client, reply, errno);
1190 DEBUG("buf->net, ");
1191 memcpy(buf, &reply, sizeof(struct nbd_reply));
1192 writeit(client->net, buf, len + sizeof(struct nbd_reply));
1199 * Set up client export array, which is an array of FILE_INFO.
1200 * Also, split a single exportfile into multiple ones, if that was asked.
1201 * @param client information on the client which we want to setup export for
1203 void setupexport(CLIENT* client) {
1205 off_t laststartoff = 0, lastsize = 0;
1206 int multifile = (client->server->flags & F_MULTIFILE);
1208 client->export = g_array_new(TRUE, TRUE, sizeof(FILE_INFO));
1210 /* If multi-file, open as many files as we can.
1211 * If not, open exactly one file.
1212 * Calculate file sizes as we go to get total size. */
1216 mode_t mode = (client->server->flags & F_READONLY) ? O_RDONLY : O_RDWR;
1219 tmpname=g_strdup_printf("%s.%d", client->exportname, i);
1221 tmpname=g_strdup(client->exportname);
1223 DEBUG2( "Opening %s\n", tmpname );
1224 fi.fhandle = open(tmpname, mode);
1225 if(fi.fhandle == -1 && mode == O_RDWR) {
1226 /* Try again because maybe media was read-only */
1227 fi.fhandle = open(tmpname, O_RDONLY);
1228 if(fi.fhandle != -1) {
1229 /* Opening the base file in copyonwrite mode is
1231 if(!(client->server->flags & F_COPYONWRITE)) {
1232 client->server->flags |= F_AUTOREADONLY;
1233 client->server->flags |= F_READONLY;
1237 if(fi.fhandle == -1) {
1238 if(multifile && i>0)
1240 err("Could not open exported file: %m");
1242 fi.startoff = laststartoff + lastsize;
1243 g_array_append_val(client->export, fi);
1246 /* Starting offset and size of this file will be used to
1247 * calculate starting offset of next file */
1248 laststartoff = fi.startoff;
1249 lastsize = size_autodetect(fi.fhandle);
1255 /* Set export size to total calculated size */
1256 client->exportsize = laststartoff + lastsize;
1258 /* Export size may be overridden */
1259 if(client->server->expected_size) {
1260 /* desired size must be <= total calculated size */
1261 if(client->server->expected_size > client->exportsize) {
1262 err("Size of exported file is too big\n");
1265 client->exportsize = client->server->expected_size;
1268 msg3(LOG_INFO, "Size of exported file/device is %llu", (unsigned long long)client->exportsize);
1270 msg3(LOG_INFO, "Total number of files: %d", i);
1274 int copyonwrite_prepare(CLIENT* client) {
1276 if ((client->difffilename = malloc(1024))==NULL)
1277 err("Failed to allocate string for diff file name");
1278 snprintf(client->difffilename, 1024, "%s-%s-%d.diff",client->exportname,client->clientname,
1280 client->difffilename[1023]='\0';
1281 msg3(LOG_INFO,"About to create map and diff file %s",client->difffilename) ;
1282 client->difffile=open(client->difffilename,O_RDWR | O_CREAT | O_TRUNC,0600) ;
1283 if (client->difffile<0) err("Could not create diff file (%m)") ;
1284 if ((client->difmap=calloc(client->exportsize/DIFFPAGESIZE,sizeof(u32)))==NULL)
1285 err("Could not allocate memory") ;
1286 for (i=0;i<client->exportsize/DIFFPAGESIZE;i++) client->difmap[i]=(u32)-1 ;
1292 * Run a command. This is used for the ``prerun'' and ``postrun'' config file
1295 * @param command the command to be ran. Read from the config file
1296 * @param file the file name we're about to export
1298 int do_run(gchar* command, gchar* file) {
1302 if(command && *command) {
1303 cmd = g_strdup_printf(command, file);
1311 * Serve a connection.
1313 * @todo allow for multithreading, perhaps use libevent. Not just yet, though;
1314 * follow the road map.
1316 * @param client a connected client
1318 void serveconnection(CLIENT *client) {
1319 if(do_run(client->server->prerun, client->exportname)) {
1322 setupexport(client);
1324 if (client->server->flags & F_COPYONWRITE) {
1325 copyonwrite_prepare(client);
1328 setmysockopt(client->net);
1331 do_run(client->server->postrun, client->exportname);
1335 * Find the name of the file we have to serve. This will use g_strdup_printf
1336 * to put the IP address of the client inside a filename containing
1337 * "%s" (in the form as specified by the "virtstyle" option). That name
1338 * is then written to client->exportname.
1340 * @param net A socket connected to an nbd client
1341 * @param client information about the client. The IP address in human-readable
1342 * format will be written to a new char* buffer, the address of which will be
1343 * stored in client->clientname.
1345 void set_peername(int net, CLIENT *client) {
1346 struct sockaddr_in addrin;
1347 struct sockaddr_in netaddr;
1348 size_t addrinlen = sizeof( addrin );
1354 if (getpeername(net, (struct sockaddr *) &addrin, (socklen_t *)&addrinlen) < 0)
1355 err("getsockname failed: %m");
1356 peername = g_strdup(inet_ntoa(addrin.sin_addr));
1357 switch(client->server->virtstyle) {
1359 client->exportname=g_strdup(client->server->exportname);
1362 for(i=0;i<strlen(peername);i++) {
1363 if(peername[i]=='.') {
1368 client->exportname=g_strdup_printf(client->server->exportname, peername);
1371 memcpy(&netaddr, &addrin, addrinlen);
1372 netaddr.sin_addr.s_addr>>=32-(client->server->cidrlen);
1373 netaddr.sin_addr.s_addr<<=32-(client->server->cidrlen);
1374 netname = inet_ntoa(netaddr.sin_addr);
1375 tmp=g_strdup_printf("%s/%s", netname, peername);
1376 client->exportname=g_strdup_printf(client->server->exportname, tmp);
1380 msg4(LOG_INFO, "connect from %s, assigned file is %s",
1381 peername, client->exportname);
1382 client->clientname=g_strdup(peername);
1388 * @param data a pointer to pid_t which should be freed
1390 void destroy_pid_t(gpointer data) {
1395 * Loop through the available servers, and serve them. Never returns.
1397 int serveloop(GArray* servers) {
1398 struct sockaddr_in addrin;
1399 socklen_t addrinlen=sizeof(addrin);
1408 * Set up the master fd_set. The set of descriptors we need
1409 * to select() for never changes anyway and it buys us a *lot*
1410 * of time to only build this once. However, if we ever choose
1411 * to not fork() for clients anymore, we may have to revisit
1416 for(i=0;i<servers->len;i++) {
1417 sock=(g_array_index(servers, SERVER, i)).socket;
1418 FD_SET(sock, &mset);
1419 max=sock>max?sock:max;
1426 memcpy(&rset, &mset, sizeof(fd_set));
1427 if(select(max+1, &rset, NULL, NULL, NULL)>0) {
1429 for(i=0;i<servers->len;i++) {
1430 serve=&(g_array_index(servers, SERVER, i));
1431 if(FD_ISSET(serve->socket, &rset)) {
1433 if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
1436 if((sock_flags = fcntl(net, F_GETFL, 0))==-1) {
1437 err("fcntl F_GETFL");
1439 if(fcntl(net, F_SETFL, sock_flags &~O_NONBLOCK)==-1) {
1440 err("fcntl F_SETFL ~O_NONBLOCK");
1442 client = g_malloc(sizeof(CLIENT));
1443 client->server=serve;
1444 client->exportsize=OFFT_MAX;
1446 set_peername(net, client);
1447 if (!authorized_client(client)) {
1448 msg2(LOG_INFO,"Unauthorized client") ;
1452 msg2(LOG_INFO,"Authorized client") ;
1453 pid=g_malloc(sizeof(pid_t));
1455 if ((*pid=fork())<0) {
1456 msg3(LOG_INFO,"Could not fork (%s)",strerror(errno)) ;
1460 if (*pid>0) { /* parent */
1462 g_hash_table_insert(children, pid, pid);
1466 g_hash_table_destroy(children);
1467 for(i=0;i<servers->len;i++) {
1468 serve=&g_array_index(servers, SERVER, i);
1469 close(serve->socket);
1471 /* FALSE does not free the
1472 actual data. This is required,
1473 because the client has a
1474 direct reference into that
1475 data, and otherwise we get a
1477 g_array_free(servers, FALSE);
1479 msg2(LOG_INFO,"Starting to serve");
1480 serveconnection(client);
1489 * Connect a server's socket.
1491 * @param serve the server we want to connect.
1493 void setup_serve(SERVER *serve) {
1494 struct sockaddr_in addrin;
1495 struct sigaction sa;
1496 int addrinlen = sizeof(addrin);
1507 if ((serve->flags) && F_SDP) {
1511 if ((serve->socket = socket(af, SOCK_STREAM, IPPROTO_TCP)) < 0)
1514 /* lose the pesky "Address already in use" error message */
1515 if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
1516 err("setsockopt SO_REUSEADDR");
1518 if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
1519 err("setsockopt SO_KEEPALIVE");
1522 /* make the listening socket non-blocking */
1523 if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
1524 err("fcntl F_GETFL");
1526 if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
1527 err("fcntl F_SETFL O_NONBLOCK");
1530 DEBUG("Waiting for connections... bind, ");
1531 addrin.sin_family = AF_INET;
1533 if(serve->flags & F_SDP) {
1534 addrin.sin_family = AF_INET_SDP;
1537 addrin.sin_port = htons(serve->port);
1538 if(!inet_aton(serve->listenaddr, &(addrin.sin_addr)))
1539 err("could not parse listen address");
1540 if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
1543 if (listen(serve->socket, 1) < 0)
1545 sa.sa_handler = sigchld_handler;
1546 sigemptyset(&sa.sa_mask);
1547 sa.sa_flags = SA_RESTART;
1548 if(sigaction(SIGCHLD, &sa, NULL) == -1)
1549 err("sigaction: %m");
1550 sa.sa_handler = sigterm_handler;
1551 sigemptyset(&sa.sa_mask);
1552 sa.sa_flags = SA_RESTART;
1553 if(sigaction(SIGTERM, &sa, NULL) == -1)
1554 err("sigaction: %m");
1558 * Connect our servers.
1560 void setup_servers(GArray* servers) {
1563 for(i=0;i<servers->len;i++) {
1564 setup_serve(&(g_array_index(servers, SERVER, i)));
1566 children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
1570 * Go daemon (unless we specified at compile time that we didn't want this)
1571 * @param serve the first server of our configuration. If its port is zero,
1572 * then do not daemonize, because we're doing inetd then. This parameter
1573 * is only used to create a PID file of the form
1574 * /var/run/nbd-server.<port>.pid; it's not modified in any way.
1576 #if !defined(NODAEMON) && !defined(NOFORK)
1577 void daemonize(SERVER* serve) {
1580 if(serve && !(serve->port)) {
1586 if(!*pidftemplate) {
1588 strncpy(pidftemplate, "/var/run/nbd-server.%d.pid", 255);
1590 strncpy(pidftemplate, "/var/run/nbd-server.pid", 255);
1593 snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
1594 pidf=fopen(pidfname, "w");
1596 fprintf(pidf,"%d\n", (int)getpid());
1600 fprintf(stderr, "Not fatal; continuing");
1604 #define daemonize(serve)
1605 #endif /* !defined(NODAEMON) && !defined(NOFORK) */
1608 * Everything beyond this point (in the file) is run in non-daemon mode.
1609 * The stuff above daemonize() isn't.
1612 void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN;
1614 void serve_err(SERVER* serve, const char* msg) {
1615 g_message("Export of %s on port %d failed:", serve->exportname,
1621 * Set up user-ID and/or group-ID
1623 void dousers(void) {
1627 gr=getgrnam(rungroup);
1629 g_message("Invalid group name: %s", rungroup);
1632 if(setgid(gr->gr_gid)<0) {
1633 g_message("Could not set GID: %s", strerror(errno));
1638 pw=getpwnam(runuser);
1640 g_message("Invalid user name: %s", runuser);
1643 if(setuid(pw->pw_uid)<0) {
1644 g_message("Could not set UID: %s", strerror(errno));
1651 * Main entry point...
1653 int main(int argc, char *argv[]) {
1658 if (sizeof( struct nbd_request )!=28) {
1659 fprintf(stderr,"Bad size of structure. Alignment problems?\n");
1660 exit(EXIT_FAILURE) ;
1663 memset(pidftemplate, '\0', 256);
1666 config_file_pos = g_strdup(CFILE);
1667 serve=cmdline(argc, argv);
1668 servers = parse_cfile(config_file_pos, &err);
1669 if(!servers || !servers->len) {
1670 g_warning("Could not parse config file: %s",
1671 err ? err->message : "Unknown error");
1674 g_array_append_val(servers, *serve);
1676 if (!(serve->port)) {
1679 /* You really should define ISSERVER if you're going to use
1680 * inetd mode, but if you don't, closing stdout and stderr
1681 * (which inetd had connected to the client socket) will let it
1685 open("/dev/null", O_WRONLY);
1686 open("/dev/null", O_WRONLY);
1688 client=g_malloc(sizeof(CLIENT));
1689 client->server=serve;
1691 client->exportsize=OFFT_MAX;
1692 set_peername(0,client);
1693 serveconnection(client);
1697 if((!serve) && (!servers||!servers->len)) {
1698 g_message("Nothing to do! Bye!");
1702 setup_servers(servers);