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 = %Ld\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)atol(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 */
519 * Remove a SERVER from memory. Used from the hash table
521 void remove_server(gpointer s) {
525 g_free(server->exportname);
527 g_free(server->authname);
532 * Parse the config file.
534 * @param f the name of the config file
535 * @param e a GError. @see CFILE_ERRORS for what error values this function can
537 * @return a Array of SERVER* pointers, If the config file is empty or does not
538 * exist, returns an empty GHashTable; if the config file contains an
539 * error, returns NULL, and e is set appropriately
541 GArray* parse_cfile(gchar* f, GError** e) {
542 const char* DEFAULT_ERROR = "Could not parse %s in group %s: %s";
543 const char* MISSING_REQUIRED_ERROR = "Could not find required value %s in group %s: %s";
545 gchar *virtstyle=NULL;
547 { "exportname", TRUE, PARAM_STRING, NULL, 0 },
548 { "port", TRUE, PARAM_INT, NULL, 0 },
549 { "authfile", FALSE, PARAM_STRING, NULL, 0 },
550 { "timeout", FALSE, PARAM_INT, NULL, 0 },
551 { "filesize", FALSE, PARAM_INT, NULL, 0 },
552 { "virtstyle", FALSE, PARAM_STRING, NULL, 0 },
553 { "prerun", FALSE, PARAM_STRING, NULL, 0 },
554 { "postrun", FALSE, PARAM_STRING, NULL, 0 },
555 { "readonly", FALSE, PARAM_BOOL, NULL, F_READONLY },
556 { "multifile", FALSE, PARAM_BOOL, NULL, F_MULTIFILE },
557 { "copyonwrite", FALSE, PARAM_BOOL, NULL, F_COPYONWRITE },
558 { "sparse_cow", FALSE, PARAM_BOOL, NULL, F_SPARSE },
559 { "sdp", FALSE, PARAM_BOOL, NULL, F_SDP },
560 { "listenaddr", FALSE, PARAM_STRING, NULL, 0 },
562 const int lp_size=sizeof(lp)/sizeof(PARAM);
564 { "user", FALSE, PARAM_STRING, &runuser, 0 },
565 { "group", FALSE, PARAM_STRING, &rungroup, 0 },
568 int p_size=sizeof(gp)/sizeof(PARAM);
571 const char *err_msg=NULL;
579 errdomain = g_quark_from_string("parse_cfile");
580 cfile = g_key_file_new();
581 retval = g_array_new(FALSE, TRUE, sizeof(SERVER));
582 if(!g_key_file_load_from_file(cfile, f, G_KEY_FILE_KEEP_COMMENTS |
583 G_KEY_FILE_KEEP_TRANSLATIONS, &err)) {
584 g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.");
585 g_key_file_free(cfile);
588 if(strcmp(g_key_file_get_start_group(cfile), "generic")) {
589 g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
590 g_key_file_free(cfile);
593 groups = g_key_file_get_groups(cfile, NULL);
594 for(i=0;groups[i];i++) {
595 memset(&s, '\0', sizeof(SERVER));
596 lp[0].target=&(s.exportname);
597 lp[1].target=&(s.port);
598 lp[2].target=&(s.authname);
599 lp[3].target=&(s.timeout);
600 lp[4].target=&(s.expected_size);
601 lp[5].target=&(virtstyle);
602 lp[6].target=&(s.prerun);
603 lp[7].target=&(s.postrun);
604 lp[8].target=lp[9].target=lp[10].target=
605 lp[11].target=lp[12].target=&(s.flags);
606 lp[13].target=&(s.listenaddr);
608 /* After the [generic] group, start parsing exports */
613 for(j=0;j<p_size;j++) {
614 g_assert(p[j].target != NULL);
615 g_assert(p[j].ptype==PARAM_INT||p[j].ptype==PARAM_STRING||p[j].ptype==PARAM_BOOL);
618 *((gint*)p[j].target) =
619 g_key_file_get_integer(cfile,
625 *((gchar**)p[j].target) =
626 g_key_file_get_string(cfile,
632 value = g_key_file_get_boolean(cfile,
634 p[j].paramname, &err);
637 *((gint*)p[j].target) |= p[j].flagval;
639 *((gint*)p[j].target) &= ~(p[j].flagval);
645 if(err->code == G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
647 /* Ignore not-found error for optional values */
651 err_msg = MISSING_REQUIRED_ERROR;
654 err_msg = DEFAULT_ERROR;
656 g_set_error(e, errdomain, CFILE_VALUE_INVALID, err_msg, p[j].paramname, groups[i], err->message);
657 g_array_free(retval, TRUE);
659 g_key_file_free(cfile);
664 if(!strncmp(virtstyle, "none", 4)) {
665 s.virtstyle=VIRT_NONE;
666 } else if(!strncmp(virtstyle, "ipliteral", 9)) {
667 s.virtstyle=VIRT_IPLIT;
668 } else if(!strncmp(virtstyle, "iphash", 6)) {
669 s.virtstyle=VIRT_IPHASH;
670 } else if(!strncmp(virtstyle, "cidrhash", 8)) {
671 s.virtstyle=VIRT_CIDR;
672 if(strlen(virtstyle)<10) {
673 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s: missing length", virtstyle, groups[i]);
674 g_array_free(retval, TRUE);
675 g_key_file_free(cfile);
678 s.cidrlen=strtol(virtstyle+8, NULL, 0);
680 g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Invalid value %s for parameter virtstyle in group %s", virtstyle, groups[i]);
681 g_array_free(retval, TRUE);
682 g_key_file_free(cfile);
686 s.virtstyle=VIRT_IPLIT;
688 /* Don't need to free this, it's not our string */
690 /* Don't append values for the [generic] group */
693 s.listenaddr = g_strdup("0.0.0.0");
695 g_array_append_val(retval, s);
698 if(s.flags & F_SDP) {
699 g_set_error(e, errdomain, CFILE_VALUE_UNSUPPORTED, "This nbd-server was built without support for SDP, yet group %s uses it", groups[i]);
700 g_array_free(retval, TRUE);
701 g_key_file_free(cfile);
710 * Signal handler for SIGCHLD
711 * @param s the signal we're handling (must be SIGCHLD, or something
714 void sigchld_handler(int s) {
719 while((pid=waitpid(-1, &status, WNOHANG)) > 0) {
720 if(WIFEXITED(status)) {
721 msg3(LOG_INFO, "Child exited with %d", WEXITSTATUS(status));
723 i=g_hash_table_lookup(children, &pid);
725 msg3(LOG_INFO, "SIGCHLD received for an unknown child with PID %ld", (long)pid);
727 DEBUG2("Removing %d from the list of children", pid);
728 g_hash_table_remove(children, &pid);
734 * Kill a child. Called from sigterm_handler::g_hash_table_foreach.
737 * @param value the value corresponding to the above key
738 * @param user_data a pointer which we always set to 1, so that we know what
741 void killchild(gpointer key, gpointer value, gpointer user_data) {
743 int *parent=user_data;
750 * Handle SIGTERM and dispatch it to our children
751 * @param s the signal we're handling (must be SIGTERM, or something
752 * is severely wrong).
754 void sigterm_handler(int s) {
757 g_hash_table_foreach(children, killchild, &parent);
767 * Detect the size of a file.
769 * @param fhandle An open filedescriptor
770 * @return the size of the file, or OFFT_MAX if detection was
773 off_t size_autodetect(int fhandle) {
775 unsigned long sectors;
776 struct stat stat_buf;
779 #ifdef HAVE_SYS_MOUNT_H
780 #ifdef HAVE_SYS_IOCTL_H
782 DEBUG("looking for export size with ioctl BLKGETSIZE\n");
783 if (!ioctl(fhandle, BLKGETSIZE, §ors) && sectors) {
784 es = (off_t)sectors * (off_t)512;
787 #endif /* BLKGETSIZE */
788 #endif /* HAVE_SYS_IOCTL_H */
789 #endif /* HAVE_SYS_MOUNT_H */
791 DEBUG("looking for fhandle size with fstat\n");
792 stat_buf.st_size = 0;
793 error = fstat(fhandle, &stat_buf);
795 if(stat_buf.st_size > 0)
796 return (off_t)stat_buf.st_size;
798 err("fstat failed: %m");
801 DEBUG("looking for fhandle size with lseek SEEK_END\n");
802 es = lseek(fhandle, (off_t)0, SEEK_END);
803 if (es > ((off_t)0)) {
806 DEBUG2("lseek failed: %d", errno==EBADF?1:(errno==ESPIPE?2:(errno==EINVAL?3:4)));
809 err("Could not find size of exported block device: %m");
814 * Get the file handle and offset, given an export offset.
816 * @param export An array of export files
817 * @param a The offset to get corresponding file/offset for
818 * @param fhandle [out] File descriptor
819 * @param foffset [out] Offset into fhandle
820 * @param maxbytes [out] Tells how many bytes can be read/written
821 * from fhandle starting at foffset (0 if there is no limit)
822 * @return 0 on success, -1 on failure
824 int get_filepos(GArray* export, off_t a, int* fhandle, off_t* foffset, size_t* maxbytes ) {
825 /* Negative offset not allowed */
829 /* Binary search for last file with starting offset <= a */
832 int end = export->len - 1;
833 while( start <= end ) {
834 int mid = (start + end) / 2;
835 fi = g_array_index(export, FILE_INFO, mid);
836 if( fi.startoff < a ) {
838 } else if( fi.startoff > a ) {
846 /* end should never go negative, since first startoff is 0 and a >= 0 */
849 fi = g_array_index(export, FILE_INFO, end);
850 *fhandle = fi.fhandle;
851 *foffset = a - fi.startoff;
853 if( end+1 < export->len ) {
854 FILE_INFO fi_next = g_array_index(export, FILE_INFO, end+1);
855 *maxbytes = fi_next.startoff - a;
862 * seek to a position in a file, with error handling.
863 * @param handle a filedescriptor
864 * @param a position to seek to
865 * @todo get rid of this; lastpoint is a global variable right now, but it
866 * shouldn't be. If we pass it on as a parameter, that makes things a *lot*
869 void myseek(int handle,off_t a) {
870 if (lseek(handle, a, SEEK_SET) < 0) {
871 err("Can not seek locally!\n");
876 * Write an amount of bytes at a given offset to the right file. This
877 * abstracts the write-side of the multiple file option.
879 * @param a The offset where the write should start
880 * @param buf The buffer to write from
881 * @param len The length of buf
882 * @param client The client we're serving for
883 * @return The number of bytes actually written, or -1 in case of an error
885 ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
890 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
892 if(maxbytes && len > maxbytes)
895 DEBUG4("(WRITE to fd %d offset %Lu len %u), ", fhandle, foffset, len);
897 myseek(fhandle, foffset);
898 return write(fhandle, buf, len);
902 * Call rawexpwrite repeatedly until all data has been written.
903 * @return 0 on success, nonzero on failure
905 int rawexpwrite_fully(off_t a, char *buf, size_t len, CLIENT *client) {
908 while(len > 0 && (ret=rawexpwrite(a, buf, len, client)) > 0 ) {
913 return (ret < 0 || len != 0);
917 * Read an amount of bytes at a given offset from the right file. This
918 * abstracts the read-side of the multiple files option.
920 * @param a The offset where the read should start
921 * @param buf A buffer to read into
922 * @param len The size of buf
923 * @param client The client we're serving for
924 * @return The number of bytes actually read, or -1 in case of an
927 ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
932 if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
934 if(maxbytes && len > maxbytes)
937 DEBUG4("(READ from fd %d offset %Lu len %u), ", fhandle, foffset, len);
939 myseek(fhandle, foffset);
940 return read(fhandle, buf, len);
944 * Call rawexpread repeatedly until all data has been read.
945 * @return 0 on success, nonzero on failure
947 int rawexpread_fully(off_t a, char *buf, size_t len, CLIENT *client) {
950 while(len > 0 && (ret=rawexpread(a, buf, len, client)) > 0 ) {
955 return (ret < 0 || len != 0);
959 * Read an amount of bytes at a given offset from the right file. This
960 * abstracts the read-side of the copyonwrite stuff, and calls
961 * rawexpread() with the right parameters to do the actual work.
962 * @param a The offset where the read should start
963 * @param buf A buffer to read into
964 * @param len The size of buf
965 * @param client The client we're going to read for
966 * @return 0 on success, nonzero on failure
968 int expread(off_t a, char *buf, size_t len, CLIENT *client) {
970 off_t mapcnt, mapl, maph, pagestart;
972 if (!(client->server->flags & F_COPYONWRITE))
973 return(rawexpread_fully(a, buf, len, client));
974 DEBUG3("Asked to read %d bytes at %Lu.\n", len, (unsigned long long)a);
976 mapl=a/DIFFPAGESIZE; maph=(a+len-1)/DIFFPAGESIZE;
978 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
979 pagestart=mapcnt*DIFFPAGESIZE;
981 rdlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
982 len : (size_t)DIFFPAGESIZE-offset;
983 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
984 DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
985 (unsigned long)(client->difmap[mapcnt]));
986 myseek(client->difffile, client->difmap[mapcnt]*DIFFPAGESIZE+offset);
987 if (read(client->difffile, buf, rdlen) != rdlen) return -1;
988 } else { /* the block is not there */
989 DEBUG2("Page %Lu is not here, we read the original one\n",
990 (unsigned long long)mapcnt);
991 if(rawexpread_fully(a, buf, rdlen, client)) return -1;
993 len-=rdlen; a+=rdlen; buf+=rdlen;
999 * Write an amount of bytes at a given offset to the right file. This
1000 * abstracts the write-side of the copyonwrite option, and calls
1001 * rawexpwrite() with the right parameters to do the actual work.
1003 * @param a The offset where the write should start
1004 * @param buf The buffer to write from
1005 * @param len The length of buf
1006 * @param client The client we're going to write for.
1007 * @return 0 on success, nonzero on failure
1009 int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
1010 char pagebuf[DIFFPAGESIZE];
1011 off_t mapcnt,mapl,maph;
1016 if (!(client->server->flags & F_COPYONWRITE))
1017 return(rawexpwrite_fully(a, buf, len, client));
1018 DEBUG3("Asked to write %d bytes at %Lu.\n", len, (unsigned long long)a);
1020 mapl=a/DIFFPAGESIZE ; maph=(a+len-1)/DIFFPAGESIZE ;
1022 for (mapcnt=mapl;mapcnt<=maph;mapcnt++) {
1023 pagestart=mapcnt*DIFFPAGESIZE ;
1024 offset=a-pagestart ;
1025 wrlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
1026 len : (size_t)DIFFPAGESIZE-offset;
1028 if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
1029 DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
1030 (unsigned long)(client->difmap[mapcnt])) ;
1031 myseek(client->difffile,
1032 client->difmap[mapcnt]*DIFFPAGESIZE+offset);
1033 if (write(client->difffile, buf, wrlen) != wrlen) return -1 ;
1034 } else { /* the block is not there */
1035 myseek(client->difffile,client->difffilelen*DIFFPAGESIZE) ;
1036 client->difmap[mapcnt]=(client->server->flags&F_SPARSE)?mapcnt:client->difffilelen++;
1037 DEBUG3("Page %Lu is not here, we put it at %lu\n",
1038 (unsigned long long)mapcnt,
1039 (unsigned long)(client->difmap[mapcnt]));
1040 rdlen=DIFFPAGESIZE ;
1041 if (rawexpread_fully(pagestart, pagebuf, rdlen, client))
1043 memcpy(pagebuf+offset,buf,wrlen) ;
1044 if (write(client->difffile, pagebuf, DIFFPAGESIZE) !=
1048 len-=wrlen ; a+=wrlen ; buf+=wrlen ;
1054 * Do the initial negotiation.
1056 * @param client The client we're negotiating with.
1058 void negotiate(CLIENT *client) {
1061 u32 flags = NBD_FLAG_HAS_FLAGS;
1063 memset(zeros, '\0', sizeof(zeros));
1064 if (write(client->net, INIT_PASSWD, 8) < 0)
1065 err("Negotiation failed: %m");
1066 cliserv_magic = htonll(cliserv_magic);
1067 if (write(client->net, &cliserv_magic, sizeof(cliserv_magic)) < 0)
1068 err("Negotiation failed: %m");
1069 size_host = htonll((u64)(client->exportsize));
1070 if (write(client->net, &size_host, 8) < 0)
1071 err("Negotiation failed: %m");
1072 if (client->server->flags & F_READONLY)
1073 flags |= NBD_FLAG_READ_ONLY;
1074 flags = htonl(flags);
1075 if (write(client->net, &flags, 4) < 0)
1076 err("Negotiation failed: %m");
1077 if (write(client->net, zeros, 124) < 0)
1078 err("Negotiation failed: %m");
1081 /** sending macro. */
1082 #define SEND(net,reply) writeit( net, &reply, sizeof( reply ));
1084 #define ERROR(client,reply,errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
1086 * Serve a file to a single client.
1088 * @todo This beast needs to be split up in many tiny little manageable
1089 * pieces. Preferably with a chainsaw.
1091 * @param client The client we're going to serve to.
1092 * @return when the client disconnects
1094 int mainloop(CLIENT *client) {
1095 struct nbd_request request;
1096 struct nbd_reply reply;
1097 gboolean go_on=TRUE;
1102 DEBUG("Entering request loop!\n");
1103 reply.magic = htonl(NBD_REPLY_MAGIC);
1112 if (client->server->timeout)
1113 alarm(client->server->timeout);
1114 readit(client->net, &request, sizeof(request));
1115 request.from = ntohll(request.from);
1116 request.type = ntohl(request.type);
1118 if (request.type==NBD_CMD_DISC) {
1119 msg2(LOG_INFO, "Disconnect request received.");
1120 if (client->server->flags & F_COPYONWRITE) {
1121 if (client->difmap) g_free(client->difmap) ;
1122 close(client->difffile);
1123 unlink(client->difffilename);
1124 free(client->difffilename);
1130 len = ntohl(request.len);
1132 if (request.magic != htonl(NBD_REQUEST_MAGIC))
1133 err("Not enough magic.");
1134 if (len > BUFSIZE + sizeof(struct nbd_reply))
1135 err("Request too big!");
1137 printf("%s from %Lu (%Lu) len %d, ", request.type ? "WRITE" :
1138 "READ", (unsigned long long)request.from,
1139 (unsigned long long)request.from / 512, len);
1141 memcpy(reply.handle, request.handle, sizeof(reply.handle));
1142 if ((request.from + len) > (OFFT_MAX)) {
1143 DEBUG("[Number too large!]");
1144 ERROR(client, reply, EINVAL);
1148 if (((ssize_t)((off_t)request.from + len) > client->exportsize)) {
1150 ERROR(client, reply, EINVAL);
1154 if (request.type==NBD_CMD_WRITE) {
1155 DEBUG("wr: net->buf, ");
1156 readit(client->net, buf, len);
1157 DEBUG("buf->exp, ");
1158 if ((client->server->flags & F_READONLY) ||
1159 (client->server->flags & F_AUTOREADONLY)) {
1160 DEBUG("[WRITE to READONLY!]");
1161 ERROR(client, reply, EPERM);
1164 if (expwrite(request.from, buf, len, client)) {
1165 DEBUG("Write failed: %m" );
1166 ERROR(client, reply, errno);
1169 SEND(client->net, reply);
1175 DEBUG("exp->buf, ");
1176 if (expread(request.from, buf + sizeof(struct nbd_reply), len, client)) {
1177 DEBUG("Read failed: %m");
1178 ERROR(client, reply, errno);
1182 DEBUG("buf->net, ");
1183 memcpy(buf, &reply, sizeof(struct nbd_reply));
1184 writeit(client->net, buf, len + sizeof(struct nbd_reply));
1191 * Set up client export array, which is an array of FILE_INFO.
1192 * Also, split a single exportfile into multiple ones, if that was asked.
1193 * @param client information on the client which we want to setup export for
1195 void setupexport(CLIENT* client) {
1197 off_t laststartoff = 0, lastsize = 0;
1198 int multifile = (client->server->flags & F_MULTIFILE);
1200 client->export = g_array_new(TRUE, TRUE, sizeof(FILE_INFO));
1202 /* If multi-file, open as many files as we can.
1203 * If not, open exactly one file.
1204 * Calculate file sizes as we go to get total size. */
1208 mode_t mode = (client->server->flags & F_READONLY) ? O_RDONLY : O_RDWR;
1211 tmpname=g_strdup_printf("%s.%d", client->exportname, i);
1213 tmpname=g_strdup(client->exportname);
1215 DEBUG2( "Opening %s\n", tmpname );
1216 fi.fhandle = open(tmpname, mode);
1217 if(fi.fhandle == -1 && mode == O_RDWR) {
1218 /* Try again because maybe media was read-only */
1219 fi.fhandle = open(tmpname, O_RDONLY);
1220 if(fi.fhandle != -1) {
1221 /* Opening the base file in copyonwrite mode is
1223 if(!(client->server->flags & F_COPYONWRITE)) {
1224 client->server->flags |= F_AUTOREADONLY;
1225 client->server->flags |= F_READONLY;
1229 if(fi.fhandle == -1) {
1230 if(multifile && i>0)
1232 err("Could not open exported file: %m");
1234 fi.startoff = laststartoff + lastsize;
1235 g_array_append_val(client->export, fi);
1238 /* Starting offset and size of this file will be used to
1239 * calculate starting offset of next file */
1240 laststartoff = fi.startoff;
1241 lastsize = size_autodetect(fi.fhandle);
1247 /* Set export size to total calculated size */
1248 client->exportsize = laststartoff + lastsize;
1250 /* Export size may be overridden */
1251 if(client->server->expected_size) {
1252 /* desired size must be <= total calculated size */
1253 if(client->server->expected_size > client->exportsize) {
1254 err("Size of exported file is too big\n");
1257 client->exportsize = client->server->expected_size;
1260 msg3(LOG_INFO, "Size of exported file/device is %Lu", (unsigned long long)client->exportsize);
1262 msg3(LOG_INFO, "Total number of files: %d", i);
1266 int copyonwrite_prepare(CLIENT* client) {
1268 if ((client->difffilename = malloc(1024))==NULL)
1269 err("Failed to allocate string for diff file name");
1270 snprintf(client->difffilename, 1024, "%s-%s-%d.diff",client->exportname,client->clientname,
1272 client->difffilename[1023]='\0';
1273 msg3(LOG_INFO,"About to create map and diff file %s",client->difffilename) ;
1274 client->difffile=open(client->difffilename,O_RDWR | O_CREAT | O_TRUNC,0600) ;
1275 if (client->difffile<0) err("Could not create diff file (%m)") ;
1276 if ((client->difmap=calloc(client->exportsize/DIFFPAGESIZE,sizeof(u32)))==NULL)
1277 err("Could not allocate memory") ;
1278 for (i=0;i<client->exportsize/DIFFPAGESIZE;i++) client->difmap[i]=(u32)-1 ;
1284 * Run a command. This is used for the ``prerun'' and ``postrun'' config file
1287 * @param command the command to be ran. Read from the config file
1288 * @param file the file name we're about to export
1290 int do_run(gchar* command, gchar* file) {
1294 if(command && *command) {
1295 cmd = g_strdup_printf(command, file);
1303 * Serve a connection.
1305 * @todo allow for multithreading, perhaps use libevent. Not just yet, though;
1306 * follow the road map.
1308 * @param client a connected client
1310 void serveconnection(CLIENT *client) {
1311 if(do_run(client->server->prerun, client->exportname)) {
1314 setupexport(client);
1316 if (client->server->flags & F_COPYONWRITE) {
1317 copyonwrite_prepare(client);
1320 setmysockopt(client->net);
1323 do_run(client->server->postrun, client->exportname);
1327 * Find the name of the file we have to serve. This will use g_strdup_printf
1328 * to put the IP address of the client inside a filename containing
1329 * "%s" (in the form as specified by the "virtstyle" option). That name
1330 * is then written to client->exportname.
1332 * @param net A socket connected to an nbd client
1333 * @param client information about the client. The IP address in human-readable
1334 * format will be written to a new char* buffer, the address of which will be
1335 * stored in client->clientname.
1337 void set_peername(int net, CLIENT *client) {
1338 struct sockaddr_in addrin;
1339 struct sockaddr_in netaddr;
1340 size_t addrinlen = sizeof( addrin );
1346 if (getpeername(net, (struct sockaddr *) &addrin, (socklen_t *)&addrinlen) < 0)
1347 err("getsockname failed: %m");
1348 peername = g_strdup(inet_ntoa(addrin.sin_addr));
1349 switch(client->server->virtstyle) {
1351 client->exportname=g_strdup(client->server->exportname);
1354 for(i=0;i<strlen(peername);i++) {
1355 if(peername[i]=='.') {
1360 client->exportname=g_strdup_printf(client->server->exportname, peername);
1363 memcpy(&netaddr, &addrin, addrinlen);
1364 netaddr.sin_addr.s_addr>>=32-(client->server->cidrlen);
1365 netaddr.sin_addr.s_addr<<=32-(client->server->cidrlen);
1366 netname = inet_ntoa(netaddr.sin_addr);
1367 tmp=g_strdup_printf("%s/%s", netname, peername);
1368 client->exportname=g_strdup_printf(client->server->exportname, tmp);
1372 msg4(LOG_INFO, "connect from %s, assigned file is %s",
1373 peername, client->exportname);
1374 client->clientname=g_strdup(peername);
1380 * @param data a pointer to pid_t which should be freed
1382 void destroy_pid_t(gpointer data) {
1387 * Loop through the available servers, and serve them. Never returns.
1389 int serveloop(GArray* servers) {
1390 struct sockaddr_in addrin;
1391 socklen_t addrinlen=sizeof(addrin);
1400 * Set up the master fd_set. The set of descriptors we need
1401 * to select() for never changes anyway and it buys us a *lot*
1402 * of time to only build this once. However, if we ever choose
1403 * to not fork() for clients anymore, we may have to revisit
1408 for(i=0;i<servers->len;i++) {
1409 sock=(g_array_index(servers, SERVER, i)).socket;
1410 FD_SET(sock, &mset);
1411 max=sock>max?sock:max;
1418 memcpy(&rset, &mset, sizeof(fd_set));
1419 if(select(max+1, &rset, NULL, NULL, NULL)>0) {
1421 for(i=0;i<servers->len;i++) {
1422 serve=&(g_array_index(servers, SERVER, i));
1423 if(FD_ISSET(serve->socket, &rset)) {
1425 if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
1428 if((sock_flags = fcntl(net, F_GETFL, 0))==-1) {
1429 err("fcntl F_GETFL");
1431 if(fcntl(net, F_SETFL, sock_flags &~O_NONBLOCK)==-1) {
1432 err("fcntl F_SETFL ~O_NONBLOCK");
1434 client = g_malloc(sizeof(CLIENT));
1435 client->server=serve;
1436 client->exportsize=OFFT_MAX;
1438 set_peername(net, client);
1439 if (!authorized_client(client)) {
1440 msg2(LOG_INFO,"Unauthorized client") ;
1444 msg2(LOG_INFO,"Authorized client") ;
1445 pid=g_malloc(sizeof(pid_t));
1447 if ((*pid=fork())<0) {
1448 msg3(LOG_INFO,"Could not fork (%s)",strerror(errno)) ;
1452 if (*pid>0) { /* parent */
1454 g_hash_table_insert(children, pid, pid);
1458 g_hash_table_destroy(children);
1459 for(i=0;i<servers->len;i++) {
1460 serve=&g_array_index(servers, SERVER, i);
1461 close(serve->socket);
1463 /* FALSE does not free the
1464 actual data. This is required,
1465 because the client has a
1466 direct reference into that
1467 data, and otherwise we get a
1469 g_array_free(servers, FALSE);
1471 msg2(LOG_INFO,"Starting to serve");
1472 serveconnection(client);
1481 * Connect a server's socket.
1483 * @param serve the server we want to connect.
1485 void setup_serve(SERVER *serve) {
1486 struct sockaddr_in addrin;
1487 struct sigaction sa;
1488 int addrinlen = sizeof(addrin);
1499 if ((serve->flags) && F_SDP) {
1503 if ((serve->socket = socket(af, SOCK_STREAM, IPPROTO_TCP)) < 0)
1506 /* lose the pesky "Address already in use" error message */
1507 if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
1508 err("setsockopt SO_REUSEADDR");
1510 if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
1511 err("setsockopt SO_KEEPALIVE");
1514 /* make the listening socket non-blocking */
1515 if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
1516 err("fcntl F_GETFL");
1518 if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
1519 err("fcntl F_SETFL O_NONBLOCK");
1522 DEBUG("Waiting for connections... bind, ");
1523 addrin.sin_family = AF_INET;
1525 if(serve->flags & F_SDP) {
1526 addrin.sin_family = AF_INET_SDP;
1529 addrin.sin_port = htons(serve->port);
1530 if(!inet_aton(serve->listenaddr, &(addrin.sin_addr)))
1531 err("could not parse listen address");
1532 if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
1535 if (listen(serve->socket, 1) < 0)
1537 sa.sa_handler = sigchld_handler;
1538 sigemptyset(&sa.sa_mask);
1539 sa.sa_flags = SA_RESTART;
1540 if(sigaction(SIGCHLD, &sa, NULL) == -1)
1541 err("sigaction: %m");
1542 sa.sa_handler = sigterm_handler;
1543 sigemptyset(&sa.sa_mask);
1544 sa.sa_flags = SA_RESTART;
1545 if(sigaction(SIGTERM, &sa, NULL) == -1)
1546 err("sigaction: %m");
1550 * Connect our servers.
1552 void setup_servers(GArray* servers) {
1555 for(i=0;i<servers->len;i++) {
1556 setup_serve(&(g_array_index(servers, SERVER, i)));
1558 children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
1562 * Go daemon (unless we specified at compile time that we didn't want this)
1563 * @param serve the first server of our configuration. If its port is zero,
1564 * then do not daemonize, because we're doing inetd then. This parameter
1565 * is only used to create a PID file of the form
1566 * /var/run/nbd-server.<port>.pid; it's not modified in any way.
1568 #if !defined(NODAEMON) && !defined(NOFORK)
1569 void daemonize(SERVER* serve) {
1572 if(serve && !(serve->port)) {
1578 if(!*pidftemplate) {
1580 strncpy(pidftemplate, "/var/run/nbd-server.%d.pid", 255);
1582 strncpy(pidftemplate, "/var/run/nbd-server.pid", 255);
1585 snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
1586 pidf=fopen(pidfname, "w");
1588 fprintf(pidf,"%d\n", (int)getpid());
1592 fprintf(stderr, "Not fatal; continuing");
1596 #define daemonize(serve)
1597 #endif /* !defined(NODAEMON) && !defined(NOFORK) */
1600 * Everything beyond this point (in the file) is run in non-daemon mode.
1601 * The stuff above daemonize() isn't.
1604 void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN;
1606 void serve_err(SERVER* serve, const char* msg) {
1607 g_message("Export of %s on port %d failed:", serve->exportname,
1613 * Set up user-ID and/or group-ID
1615 void dousers(void) {
1619 gr=getgrnam(rungroup);
1621 g_message("Invalid group name: %s", rungroup);
1624 if(setgid(gr->gr_gid)<0) {
1625 g_message("Could not set GID: %s", strerror(errno));
1630 pw=getpwnam(runuser);
1632 g_message("Invalid user name: %s", runuser);
1635 if(setuid(pw->pw_uid)<0) {
1636 g_message("Could not set UID: %s", strerror(errno));
1643 * Main entry point...
1645 int main(int argc, char *argv[]) {
1650 if (sizeof( struct nbd_request )!=28) {
1651 fprintf(stderr,"Bad size of structure. Alignment problems?\n");
1652 exit(EXIT_FAILURE) ;
1655 memset(pidftemplate, '\0', 256);
1658 config_file_pos = g_strdup(CFILE);
1659 serve=cmdline(argc, argv);
1660 servers = parse_cfile(config_file_pos, &err);
1661 if(!servers || !servers->len) {
1662 g_warning("Could not parse config file: %s",
1663 err ? err->message : "Unknown error");
1666 g_array_append_val(servers, *serve);
1668 if (!(serve->port)) {
1671 /* You really should define ISSERVER if you're going to use
1672 * inetd mode, but if you don't, closing stdout and stderr
1673 * (which inetd had connected to the client socket) will let it
1677 open("/dev/null", O_WRONLY);
1678 open("/dev/null", O_WRONLY);
1680 client=g_malloc(sizeof(CLIENT));
1681 client->server=serve;
1683 client->exportsize=OFFT_MAX;
1684 set_peername(0,client);
1685 serveconnection(client);
1689 if((!serve) && (!servers||!servers->len)) {
1690 g_message("Nothing to do! Bye!");
1694 setup_servers(servers);