#define MY_NAME "nbd_server"
#include "cliserv.h"
+/** Default position of the config file */
+#ifndef SYSCONFDIR
+#define SYSCONFDIR "/etc"
+#endif
+#define CFILE SYSCONFDIR "/nbd-server/config"
+
+/** Where our config file actually is */
+gchar* config_file_pos;
+
/** how much space for child PIDs we have by default. Dynamically
allocated, and will be realloc()ed if out of space, so this should
probably be fair for most situations. */
* Variables associated with a server.
**/
typedef struct {
- char* exportname; /**< (unprocessed) filename of the file we're exporting */
+ gchar* exportname; /**< (unprocessed) filename of the file we're exporting */
off_t hunksize; /**< size of a hunk of an exported file */
off_t expected_size; /**< size of the exported file as it was told to
us through configuration */
} CLIENT;
/**
+ * Type of configuration file values
+ **/
+typedef enum {
+ PARAM_INT, /**< This parameter is an integer */
+ PARAM_STRING, /**< This parameter is a string */
+ PARAM_BOOL, /**< This parameter is a boolean */
+} PARAM_TYPE;
+/**
+ * Configuration file values
+ **/
+typedef struct {
+ gchar *paramname; /**< Name of the parameter, as it appears in
+ the config file */
+ gboolean required; /**< Whether this is a required (as opposed to
+ optional) parameter */
+ PARAM_TYPE ptype; /**< Type of the parameter. */
+ gpointer target; /**< Pointer to where the data of this
+ parameter should be written. If ptype is
+ PARAM_BOOL, the data is or'ed rather than
+ overwritten. */
+ gint flagval; /**< Flag mask for this parameter in case ptype
+ is PARAM_BOOL. */
+} PARAM;
+
+/**
* Check whether a client is allowed to connect. Works with an authorization
* file which contains one line per machine, no wildcards.
*
- * @param name IP address of client trying to connect (in human-readable form)
+ * @param opts The client who's trying to connect.
* @return 0 - authorization refused, 1 - OK
**/
int authorized_client(CLIENT *opts) {
*/
void usage() {
printf("This is nbd-server version " VERSION "\n");
- printf("Usage: port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-a timeout_sec]\n"
+ printf("Usage: port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-a timeout_sec] [-C configuration file]\n"
"\t-r|--read-only\t\tread only\n"
"\t-m|--multi-file\t\tmultiple file\n"
"\t-c|--copy-on-write\tcopy on write\n"
+ "\t-C|--config-file\tspecify an alternat configuration file\n"
"\t-l|--authorize-file\tfile with list of hosts that are allowed to\n\t\t\t\tconnect.\n"
"\t-a|--idle-time\t\tmaximum idle seconds; server terminates when\n\t\t\t\tidle time exceeded\n\n"
"\tif port is set to 0, stdin is used (for running from inetd)\n"
"\tif file_to_export contains '%%s', it is substituted with the IP\n"
"\t\taddress of the machine trying to connect\n" );
+ printf("Using configuration file %s\n", CFILE);
}
/**
* Parse the command line.
*
- * @todo getopt() is a great thing, and easy to use. Also, we want to
- * create a configuration file which nbd-server will read. Maybe do (as in,
- * parse) that here.
- *
* @param argc the argc argument to main()
* @param argv the argv argument to main()
**/
SERVER* cmdline(int argc, char *argv[]) {
int i=0;
+ int nonspecial=0;
int c;
struct option long_options[] = {
{"read-only", no_argument, NULL, 'r'},
{"copy-on-write", no_argument, NULL, 'c'},
{"authorize-file", required_argument, NULL, 'l'},
{"idle-time", required_argument, NULL, 'a'},
+ {"config-file", required_argument, NULL, 'C'},
{0,0,0,0}
};
SERVER *serve;
+ off_t es;
+ size_t last;
+ char suffix;
- serve=g_malloc(sizeof(SERVER));
+ if(argc==1) {
+ return NULL;
+ }
+ serve=g_new0(SERVER, 1);
serve->hunksize=OFFT_MAX;
- while((c=getopt_long(argc, argv, "a:cl:mr", long_options, &i))>=0) {
+ serve->authname = g_strdup(default_authname);
+ while((c=getopt_long(argc, argv, "-a:C:cl:mr", long_options, &i))>=0) {
switch (c) {
+ case 1:
+ /* non-option argument */
+ switch(nonspecial++) {
+ case 0:
+ serve->port=strtol(optarg, NULL, 0);
+ break;
+ case 1:
+ serve->exportname = g_strdup(optarg);
+ if(serve->exportname[0] != '/') {
+ fprintf(stderr, "E: The to be exported file needs to be an absolute filename!\n");
+ exit(EXIT_FAILURE);
+ }
+ break;
+ case 2:
+ last=strlen(optarg)-1;
+ suffix=optarg[last];
+ if (suffix == 'k' || suffix == 'K' ||
+ suffix == 'm' || suffix == 'M')
+ optarg[last] = '\0';
+ es = (off_t)atol(optarg);
+ switch (suffix) {
+ case 'm':
+ case 'M': es <<= 10;
+ case 'k':
+ case 'K': es <<= 10;
+ default : break;
+ }
+ serve->expected_size = es;
+ break;
+ }
+ break;
case 'r':
serve->flags |= F_READONLY;
break;
case 'm':
serve->flags |= F_MULTIFILE;
serve->hunksize = 1*GIGA;
- serve->authname = default_authname;
break;
case 'c':
serve->flags |=F_COPYONWRITE;
break;
+ case 'C':
+ g_free(config_file_pos);
+ config_file_pos=g_strdup(optarg);
+ break;
case 'l':
- serve->authname=optarg;
+ g_free(serve->authname);
+ serve->authname=g_strdup(optarg);
break;
case 'a':
serve->timeout=strtol(optarg, NULL, 0);
break;
default:
usage();
- exit(0);
+ exit(EXIT_FAILURE);
break;
}
}
/* What's left: the port to export, the name of the to be exported
* file, and, optionally, the size of the file, in that order. */
- if(++i>=argc) {
- usage();
- exit(0);
- }
- serve->port=strtol(argv[i], NULL, 0);
- if(++i>=argc) {
- usage();
- exit(0);
- }
- serve->exportname = argv[i];
- if(serve->exportname[0] != '/') {
- fprintf(stderr, "E: The to be exported file needs to be an absolute filename!\n");
- exit(EXIT_FAILURE);
+ if(nonspecial<2) {
+ g_free(serve);
+ serve=NULL;
}
- if(++i<argc) {
- off_t es;
- size_t last = strlen(argv[i])-1;
- char suffix = argv[i][last];
- if (suffix == 'k' || suffix == 'K' ||
- suffix == 'm' || suffix == 'M')
- argv[i][last] = '\0';
- es = (off_t)atol(argv[i]);
- switch (suffix) {
- case 'm':
- case 'M': es <<= 10;
- case 'k':
- case 'K': es <<= 10;
- default : break;
+ return serve;
+}
+
+/**
+ * Error codes for config file parsing
+ **/
+typedef enum {
+ CFILE_NOTFOUND, /**< The configuration file is not found */
+ CFILE_MISSING_GENERIC, /**< The (required) group "generic" is missing */
+ CFILE_KEY_MISSING, /**< A (required) key is missing */
+ CFILE_VALUE_INVALID, /**< A value is syntactically invalid */
+ CFILE_PROGERR /**< Programmer error */
+} CFILE_ERRORS;
+
+/**
+ * Remove a SERVER from memory. Used from the hash table
+ **/
+void remove_server(gpointer s) {
+ SERVER *server;
+
+ server=(SERVER*)s;
+ g_free(server->exportname);
+ if(server->authname)
+ g_free(server->authname);
+ g_free(server);
+}
+
+/**
+ * Parse the config file.
+ *
+ * @param f the name of the config file
+ * @param e a GError. @see CFILE_ERRORS for what error values this function can
+ * return.
+ * @return a GHashTable of SERVER* pointers, with the port number as the hash
+ * key. If the config file is empty or does not exist, returns an empty
+ * GHashTable; if the config file contains an error, returns NULL, and
+ * e is set appropriately
+ **/
+GArray* parse_cfile(gchar* f, GError** e) {
+ SERVER s;
+ PARAM p[] = {
+ { "exportname", TRUE, PARAM_STRING, NULL, 0 },
+ { "port", TRUE, PARAM_INT, NULL, 0 },
+ { "authfile", FALSE, PARAM_STRING, NULL, 0 },
+ { "timeout", FALSE, PARAM_INT, NULL, 0 },
+ { "filesize", FALSE, PARAM_INT, NULL, 0 },
+ { "readonly", FALSE, PARAM_BOOL, NULL, F_READONLY },
+ { "multifile", FALSE, PARAM_BOOL, NULL, F_MULTIFILE },
+ { "copyonwrite", FALSE, PARAM_BOOL, NULL, F_COPYONWRITE },
+ };
+ const int p_size=8;
+ GKeyFile *cfile;
+ GError *err = NULL;
+ GQuark errdomain;
+ GArray *retval=NULL;
+ gchar **groups;
+ gboolean value;
+ gint i,j;
+
+ memset(&s, '\0', sizeof(SERVER));
+ errdomain = g_quark_from_string("parse_cfile");
+ cfile = g_key_file_new();
+ retval = g_array_new(FALSE, TRUE, sizeof(SERVER));
+ if(!g_key_file_load_from_file(cfile, f, G_KEY_FILE_KEEP_COMMENTS |
+ G_KEY_FILE_KEEP_TRANSLATIONS, &err)) {
+ g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.");
+ g_key_file_free(cfile);
+ return retval;
+ }
+ if(strcmp(g_key_file_get_start_group(cfile), "generic")) {
+ g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
+ g_key_file_free(cfile);
+ return NULL;
+ }
+ groups = g_key_file_get_groups(cfile, NULL);
+ for(i=1;groups[i];i++) {
+ p[0].target=&(s.exportname);
+ p[1].target=&(s.port);
+ p[2].target=&(s.authname);
+ p[3].target=&(s.timeout);
+ p[4].target=&(s.expected_size);
+ p[5].target=p[6].target=p[7].target=p[8].target=&(s.flags);
+ for(j=0;j<p_size;j++) {
+ g_assert(p[j].target != NULL);
+ g_assert(p[j].ptype==PARAM_INT||p[j].ptype==PARAM_STRING||p[j].ptype==PARAM_BOOL);
+ switch(p[j].ptype) {
+ case PARAM_INT:
+ *((gint*)p[j].target) =
+ g_key_file_get_integer(cfile,
+ groups[i],
+ p[j].paramname,
+ &err);
+ break;
+ case PARAM_STRING:
+ *((gchar**)p[j].target) =
+ g_key_file_get_string(cfile,
+ groups[i],
+ p[j].paramname,
+ &err);
+ break;
+ case PARAM_BOOL:
+ value = g_key_file_get_boolean(cfile,
+ groups[i],
+ p[j].paramname, &err);
+ if(!err) {
+ *((gint*)p[j].target) |= value;
+ }
+ break;
+ }
+ if(err) {
+ if(err->code == G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
+ if(p[j].required) {
+ g_set_error(e, errdomain, CFILE_KEY_MISSING, "Could not find required value %s in group %s: %s", p[j].paramname, groups[i], err->message);
+ g_array_free(retval, TRUE);
+ g_error_free(err);
+ g_key_file_free(cfile);
+ return NULL;
+ } else {
+ g_clear_error(&err);
+ continue;
+ }
+ g_set_error(e, errdomain, CFILE_VALUE_INVALID, "Could not parse %s in group %s: %s", p[j].paramname, groups[i], err->message);
+ g_array_free(retval, TRUE);
+ g_error_free(err);
+ g_key_file_free(cfile);
+ return NULL;
+ }
+ }
}
- serve->expected_size = es;
+ g_array_append_val(retval, s);
}
- return serve;
+ return retval;
}
/**
* @param a The offset where the write should start
* @param buf The buffer to write from
* @param len The length of buf
+ * @param client The client we're serving for
* @return The number of bytes actually written, or -1 in case of an error
**/
int rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
* @param a The offset where the read should start
* @param buf A buffer to read into
* @param len The size of buf
+ * @param client The client we're serving for
* @return The number of bytes actually read, or -1 in case of an
* error.
**/
* @param a The offset where the read should start
* @param buf A buffer to read into
* @param len The size of buf
+ * @param client The client we're going to read for
* @return The number of bytes actually read, or -1 in case of an error
**/
int expread(off_t a, char *buf, size_t len, CLIENT *client) {
* @param a The offset where the write should start
* @param buf The buffer to write from
* @param len The length of buf
+ * @param client The client we're going to write for.
* @return The number of bytes actually written, or -1 in case of an error
**/
int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
/**
* Do the initial negotiation.
*
- * @param net A socket to do the negotiation over
+ * @param client The client we're negotiating with.
**/
void negotiate(CLIENT *client) {
char zeros[300];
* @todo This beast needs to be split up in many tiny little manageable
* pieces. Preferably with a chainsaw.
*
- * @param net A network socket, connected to an nbd client
+ * @param client The client we're going to serve to.
* @return never
**/
int mainloop(CLIENT *client) {
if (request.magic != htonl(NBD_REQUEST_MAGIC))
err("Not enough magic.");
- if (len > BUFSIZE)
+ if (len > BUFSIZE + sizeof(struct nbd_reply))
err("Request too big!");
#ifdef DODBG
printf("%s from %Lu (%Lu) len %d, ", request.type ? "WRITE" :
}
return 0;
}
-int copyonwrite_prepare(CLIENT* client)
-{
+
+int copyonwrite_prepare(CLIENT* client) {
off_t i;
if ((client->difffilename = malloc(1024))==NULL)
err("Failed to allocate string for diff file name");
* @todo allow for multithreading, perhaps use libevent. Not just yet, though;
* follow the road map.
*
- * @param net A network socket connected to an nbd client
+ * @param client a connected client
**/
void serveconnection(CLIENT *client) {
splitexport(client);
/**
* Go daemon (unless we specified at compile time that we didn't want this)
* @param serve the first server of our configuration. If its port is zero,
- * then do not daemonize, because we're doing inetd then.
+ * then do not daemonize, because we're doing inetd then. This parameter
+ * is only used to create a PID file of the form
+ * /var/run/nbd-server.<port>.pid; it's not modified in any way.
**/
#if !defined(NODAEMON) && !defined(NOFORK)
void daemonize(SERVER* serve) {
FILE*pidf;
- if((serve->port)) {
- if(daemon(0,0)<0) {
- err("daemon");
- }
+ if(daemon(0,0)<0) {
+ err("daemon");
+ }
+ if(serve) {
snprintf(pidfname, sizeof(char)*255, "/var/run/nbd-server.%d.pid", serve->port);
- pidf=fopen(pidfname, "w");
- if(pidf) {
- fprintf(pidf,"%d", (int)getpid());
- fclose(pidf);
- } else {
- perror("fopen");
- fprintf(stderr, "Not fatal; continuing");
- }
+ } else {
+ strncpy(pidfname, "/var/run/nbd-server.pid", sizeof(char)*255);
+ }
+ pidf=fopen(pidfname, "w");
+ if(pidf) {
+ fprintf(pidf,"%d\n", (int)getpid());
+ fclose(pidf);
+ } else {
+ perror("fopen");
+ fprintf(stderr, "Not fatal; continuing");
}
}
#else
/**
* Connect a server's socket.
*
- * @todo modularize this giant beast. Preferably with a chainsaw. Also,
- * it has no business starting mainloop(), through serveconnection(); it
- * should connect, and be done with it.
- *
* @param serve the server we want to connect.
**/
-void setup_serve(SERVER* serve) {
+void setup_serve(SERVER *serve) {
struct sockaddr_in addrin;
struct sigaction sa;
int addrinlen = sizeof(addrin);
#else
char yes='1';
#endif /* sun */
-
if ((serve->socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
err("socket: %m");
}
/**
+ * Connect our servers.
+ **/
+void setup_servers(GArray* servers) {
+ int i;
+
+ for(i=0;i<servers->len;i++) {
+ setup_serve(&(g_array_index(servers, SERVER, i)));
+ }
+}
+
+/**
* Loop through the available servers, and serve them.
- *
- * Actually, right now we only handle one server. Will change that for
- * 2.9.
**/
-int serveloop(SERVER* serve) {
+int serveloop(GArray* servers) {
struct sockaddr_in addrin;
socklen_t addrinlen=sizeof(addrin);
+ SERVER *serve;
+ int i, max, sock;
+ fd_set mset, rset;
+ struct timeval tv;
+
+ /*
+ * Set up the master fd_set. The set of descriptors we need
+ * to select() for never changes anyway and it buys us a *lot*
+ * of time to only build this once. However, if we ever choose
+ * to not fork() for clients anymore, we may have to revisit
+ * this.
+ */
+ max=0;
+ FD_ZERO(&mset);
+ for(i=0;i<servers->len;i++) {
+ sock=(g_array_index(servers, SERVER, i)).socket;
+ FD_SET(sock, &mset);
+ max=sock>max?sock:max;
+ }
for(;;) {
CLIENT *client;
int net;
pid_t *pid;
- DEBUG("accept, ");
- if ((net = accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
- err("accept: %m");
-
- client = g_malloc(sizeof(CLIENT));
- client->server=serve;
- client->exportsize=OFFT_MAX;
- client->net=net;
- set_peername(net, client);
- if (!authorized_client(client)) {
- msg2(LOG_INFO,"Unauthorized client") ;
- close(net) ;
- continue ;
- }
- msg2(LOG_INFO,"Authorized client") ;
- pid=g_malloc(sizeof(pid_t));
+ memcpy(&rset, &mset, sizeof(fd_set));
+ tv.tv_sec=0;
+ tv.tv_usec=500;
+ if(select(max+1, &rset, NULL, NULL, &tv)>0) {
+ DEBUG("accept, ");
+ for(i=0;i<servers->len;i++) {
+ serve=&(g_array_index(servers, SERVER, i));
+ if(FD_ISSET(serve->socket, &rset)) {
+ if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
+ err("accept: %m");
+
+ client = g_malloc(sizeof(CLIENT));
+ client->server=serve;
+ client->exportsize=OFFT_MAX;
+ client->net=net;
+ set_peername(net, client);
+ if (!authorized_client(client)) {
+ msg2(LOG_INFO,"Unauthorized client") ;
+ close(net);
+ continue;
+ }
+ msg2(LOG_INFO,"Authorized client") ;
+ pid=g_malloc(sizeof(pid_t));
#ifndef NOFORK
- if ((*pid=fork())<0) {
- msg3(LOG_INFO,"Could not fork (%s)",strerror(errno)) ;
- close(net) ;
- continue ;
- }
- if (*pid>0) { /* parent */
- close(net);
- g_hash_table_insert(children, pid, pid);
- continue;
- }
- /* child */
- g_hash_table_destroy(children);
- close(serve->socket) ;
+ if ((*pid=fork())<0) {
+ msg3(LOG_INFO,"Could not fork (%s)",strerror(errno)) ;
+ close(net);
+ continue;
+ }
+ if (*pid>0) { /* parent */
+ close(net);
+ g_hash_table_insert(children, pid, pid);
+ continue;
+ }
+ /* child */
+ g_hash_table_destroy(children);
+ for(i=0;i<servers->len,serve=(g_array_index(servers, SERVER*, i));i++) {
+ close(serve->socket);
+ }
+ /* FALSE does not free the
+ actual data. This is required,
+ because the client has a
+ direct reference into that
+ data, and otherwise we get a
+ segfault... */
+ g_array_free(servers, FALSE);
#endif // NOFORK
- msg2(LOG_INFO,"Starting to serve") ;
- serveconnection(client);
+ msg2(LOG_INFO,"Starting to serve");
+ serveconnection(client);
+ }
+ }
+ }
}
}
* Main entry point...
**/
int main(int argc, char *argv[]) {
- SERVER* serve;
- GArray* servers;
+ SERVER *serve;
+ GArray *servers;
+ GError *err=NULL;
if (sizeof( struct nbd_request )!=28) {
fprintf(stderr,"Bad size of structure. Alignment problems?\n");
}
logging();
+ config_file_pos = g_strdup(CFILE);
serve=cmdline(argc, argv);
- servers=g_array_new(TRUE, FALSE, sizeof(SERVER*));
+ servers = parse_cfile(config_file_pos, &err);
+ if(!servers || !servers->len) {
+ g_warning("Could not parse config file: %s", err->message);
+ }
+ if(serve) {
+ g_array_append_val(servers, *serve);
+ }
+/* We don't support this at this time */
+#if 0
if (!(serve->port)) {
CLIENT *client;
#ifndef ISSERVER
serveconnection(client);
return 0;
}
+#endif
+ if((!serve) && (!servers||!servers->len)) {
+ g_message("Nothing to do! Bye!");
+ exit(EXIT_FAILURE);
+ }
daemonize(serve);
- setup_serve(serve);
- serveloop(serve);
+ setup_servers(servers);
+ serveloop(servers);
return 0 ;
}