Initial implementation of named exports
[nbd.git] / nbd-server.c
index 70db6d1..f07a29f 100644 (file)
@@ -159,6 +159,13 @@ char pidfname[256]; /**< name of our PID file */
 char pidftemplate[256]; /**< template to be used for the filename of the PID file */
 char default_authname[] = SYSCONFDIR "/nbd-server/allow"; /**< default name of allow file */
 
+int modernsock=0;        /**< Socket for the modern handler. Not used
+                              if a client was only specified on the
+                              command line; only port used if
+                              oldstyle is set to false (and then the
+                              command-line client isn't used, gna gna) */
+char* modern_listen;     /**< listenaddr value for modernsock */
+
 /**
  * Types of virtuatlization
  **/
@@ -190,6 +197,7 @@ typedef struct {
                                  but before starting to serve */
        gchar* postrun;      /**< command that will be ran after the client
                                  disconnects */
+       gchar* servename;    /**< name of the export as selected by nbd-client */
 } SERVER;
 
 /**
@@ -215,6 +223,7 @@ typedef struct {
                               make -m and -c mutually exclusive */
        u32 difffilelen;     /**< number of pages in difffile */
        u32 *difmap;         /**< see comment on the global difmap for this one */
+       gboolean modern;     /**< client was negotiated using modern negotiation protocol */
 } CLIENT;
 
 /**
@@ -525,8 +534,10 @@ typedef enum {
        CFILE_VALUE_INVALID,    /**< A value is syntactically invalid */
        CFILE_VALUE_UNSUPPORTED,/**< A value is not supported in this build */
        CFILE_PROGERR,          /**< Programmer error */
-       CFILE_NO_EXPORTS        /**< A config file was specified that does not
+       CFILE_NO_EXPORTS,       /**< A config file was specified that does not
                                     define any exports */
+       CFILE_INCORRECT_PORT,   /**< The reserved port was specified for an
+                                    old-style export. */
 } CFILE_ERRORS;
 
 /**
@@ -593,8 +604,7 @@ SERVER* dup_serve(SERVER *s) {
  * @param a server array
  * @return 0 success, -1 error
  */
-int append_serve(SERVER *s, GArray *a)
-{
+int append_serve(SERVER *s, GArray *a) {
        SERVER *ns = NULL;
        struct addrinfo hints;
        struct addrinfo *ai = NULL;
@@ -686,9 +696,12 @@ GArray* parse_cfile(gchar* f, GError** e) {
                { "listenaddr", FALSE,  PARAM_STRING,   NULL, 0 },
        };
        const int lp_size=sizeof(lp)/sizeof(PARAM);
+       int do_oldstyle;
        PARAM gp[] = {
                { "user",       FALSE, PARAM_STRING,    &runuser,       0 },
                { "group",      FALSE, PARAM_STRING,    &rungroup,      0 },
+               { "oldstyle",   FALSE, PARAM_BOOL,      &do_oldstyle,   1 },
+               { "listenaddr", FALSE, PARAM_STRING,    &modern_listen, 0 },
        };
        PARAM* p=gp;
        int p_size=sizeof(gp)/sizeof(PARAM);
@@ -769,6 +782,11 @@ GArray* parse_cfile(gchar* f, GError** e) {
                                        }
                                        break;
                        }
+                       if(!strcmp(p[j].paramname, "port") && !strcmp(p[j].target, NBD_DEFAULT_PORT)) {
+                               g_set_error(e, errdomain, CFILE_INCORRECT_PORT, "Config file specifies default port for oldstyle export");
+                               g_key_file_free(cfile);
+                               return NULL;
+                       }
                        if(err) {
                                if(err->code == G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
                                        if(!p[j].required) {
@@ -818,8 +836,13 @@ GArray* parse_cfile(gchar* f, GError** e) {
                /* Don't append values for the [generic] group */
                if(i>0) {
                        s.socket_family = AF_UNSPEC;
+                       s.servename = groups[i];
 
                        append_serve(&s, retval);
+               } else {
+                       if(!do_oldstyle) {
+                               lp[1].required = 0;
+                       }
                }
 #ifndef WITH_SDP
                if(s.flags & F_SDP) {
@@ -1190,19 +1213,69 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
  *
  * @param client The client we're negotiating with.
  **/
-void negotiate(CLIENT *client) {
+CLIENT* negotiate(int net, CLIENT *client, GArray* servers) {
        char zeros[128];
-       u64 size_host;
-       u32 flags = NBD_FLAG_HAS_FLAGS;
+       uint64_t size_host;
+       uint32_t flags = NBD_FLAG_HAS_FLAGS;
+       uint16_t smallflags = 0;
 
        memset(zeros, '\0', sizeof(zeros));
-       if (write(client->net, INIT_PASSWD, 8) < 0)
-               err("Negotiation failed: %m");
-       cliserv_magic = htonll(cliserv_magic);
-       if (write(client->net, &cliserv_magic, sizeof(cliserv_magic)) < 0)
-               err("Negotiation failed: %m");
+       if(!client || !client->modern) {
+               if (write(net, INIT_PASSWD, 8) < 0) {
+                       err_nonfatal("Negotiation failed: %m");
+                       if(client)
+                               exit(EXIT_FAILURE);
+               }
+               cliserv_magic = htonll(cliserv_magic);
+               if (write(net, &cliserv_magic, sizeof(cliserv_magic)) < 0) {
+                       err_nonfatal("Negotiation failed: %m");
+                       if(client)
+                               exit(EXIT_FAILURE);
+               }
+       }
+       if(!client) {
+               uint64_t reserved;
+               uint64_t magic;
+               uint32_t opt;
+               uint64_t namelen;
+               char* name;
+               int i;
+
+               if(!servers)
+                       err("programmer error");
+               write(net, &smallflags, sizeof(uint16_t));
+               read(net, &reserved, sizeof(reserved));
+               read(net, &magic, sizeof(magic));
+               magic = ntohll(magic);
+               if(magic != cliserv_magic) {
+                       close(net);
+                       return NULL;
+               }
+               read(net, &opt, sizeof(opt));
+               opt = ntohl(opt);
+               if(opt != NBD_OPT_EXPORT_NAME) {
+                       close(net);
+                       return NULL;
+               }
+               read(net, &namelen, sizeof(namelen));
+               namelen = ntohll(namelen);
+               name = malloc(namelen+1);
+               name[namelen+1]=0;
+               read(net, &name, namelen);
+               for(i=0; i<servers->len; i++) {
+                       SERVER* serve = &(g_array_index(servers, SERVER, i));
+                       if(!strcmp(serve->servename, name)) {
+                               CLIENT* client = g_new0(CLIENT, 1);
+                               client->server = serve;
+                               client->exportsize = OFFT_MAX;
+                               client->net = net;
+                               client->modern = TRUE;
+                               return client;
+                       }
+               }
+       }
        size_host = htonll((u64)(client->exportsize));
-       if (write(client->net, &size_host, 8) < 0)
+       if (write(net, &size_host, 8) < 0)
                err("Negotiation failed: %m");
        if (client->server->flags & F_READONLY)
                flags |= NBD_FLAG_READ_ONLY;
@@ -1211,6 +1284,7 @@ void negotiate(CLIENT *client) {
                err("Negotiation failed: %m");
        if (write(client->net, zeros, 124) < 0)
                err("Negotiation failed: %m");
+       return NULL;
 }
 
 /** sending macro. */
@@ -1233,7 +1307,7 @@ int mainloop(CLIENT *client) {
 #ifdef DODBG
        int i = 0;
 #endif
-       negotiate(client);
+       negotiate(client->net, client, NULL);
        DEBUG("Entering request loop!\n");
        reply.magic = htonl(NBD_REPLY_MAGIC);
        reply.error = 0;
@@ -1569,7 +1643,6 @@ void destroy_pid_t(gpointer data) {
 int serveloop(GArray* servers) {
        struct sockaddr_storage addrin;
        socklen_t addrinlen=sizeof(addrin);
-       SERVER *serve;
        int i;
        int max;
        int sock;
@@ -1590,88 +1663,125 @@ int serveloop(GArray* servers) {
                FD_SET(sock, &mset);
                max=sock>max?sock:max;
        }
+       if(modernsock) {
+               FD_SET(modernsock, &mset);
+               max=modernsock>max?sock:max;
+       }
        for(;;) {
-               CLIENT *client;
-               int net;
+               CLIENT *client = NULL;
                pid_t *pid;
 
                memcpy(&rset, &mset, sizeof(fd_set));
                if(select(max+1, &rset, NULL, NULL, NULL)>0) {
+                       int net = 0;
+                       SERVER* serve;
+
                        DEBUG("accept, ");
-                       for(i=0;i<servers->len;i++) {
+                       if(FD_ISSET(modernsock, &rset)) {
+                               if((net=accept(modernsock, (struct sockaddr *) &addrin, &addrinlen)) < 0)
+                                       err("accept: %m");
+                               client = negotiate(net, NULL, servers);
+                               if(!client) {
+                                       err_nonfatal("negotiation failed");
+                                       close(net);
+                               }
+                       }
+                       for(i=0;i<servers->len && !net;i++) {
                                serve=&(g_array_index(servers, SERVER, i));
                                if(FD_ISSET(serve->socket, &rset)) {
-                                       int sock_flags;
                                        if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
                                                err("accept: %m");
+                               }
+                       }
+                       if(net) {
+                               int sock_flags;
 
-                                       if((sock_flags = fcntl(net, F_GETFL, 0))==-1) {
-                                               err("fcntl F_GETFL");
-                                       }
-                                       if(fcntl(net, F_SETFL, sock_flags &~O_NONBLOCK)==-1) {
-                                               err("fcntl F_SETFL ~O_NONBLOCK");
-                                       }
-                                       client = g_malloc(sizeof(CLIENT));
+                               if((sock_flags = fcntl(net, F_GETFL, 0))==-1) {
+                                       err("fcntl F_GETFL");
+                               }
+                               if(fcntl(net, F_SETFL, sock_flags &~O_NONBLOCK)==-1) {
+                                       err("fcntl F_SETFL ~O_NONBLOCK");
+                               }
+                               if(!client) {
+                                       client = g_new0(CLIENT, 1);
                                        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));
+                               }
+                               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);
-                                       for(i=0;i<servers->len;i++) {
-                                               serve=&g_array_index(servers, SERVER, 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);
-                                       exit(EXIT_SUCCESS);
+                               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;i++) {
+                                       serve=&g_array_index(servers, SERVER, 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);
+                               exit(EXIT_SUCCESS);
                        }
                }
        }
 }
 
+void dosockopts(int socket) {
+#ifndef sun
+       int yes=1;
+#else
+       char yes='1';
+#endif /* sun */
+       int sock_flags;
+
+       /* lose the pesky "Address already in use" error message */
+       if (setsockopt(socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
+               err("setsockopt SO_REUSEADDR");
+       }
+       if (setsockopt(socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
+               err("setsockopt SO_KEEPALIVE");
+       }
+
+       /* make the listening socket non-blocking */
+       if ((sock_flags = fcntl(socket, F_GETFL, 0)) == -1) {
+               err("fcntl F_GETFL");
+       }
+       if (fcntl(socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
+               err("fcntl F_SETFL O_NONBLOCK");
+       }
+}
+
 /**
  * Connect a server's socket.
  *
  * @param serve the server we want to connect.
  **/
-void setup_serve(SERVER *serve) {
+int setup_serve(SERVER *serve) {
        struct addrinfo hints;
        struct addrinfo *ai = NULL;
-       struct sigaction sa;
-       int sock_flags;
-#ifndef sun
-       int yes=1;
-#else
-       char yes='1';
-#endif /* sun */
        gchar *port = NULL;
        int e;
 
@@ -1682,7 +1792,7 @@ void setup_serve(SERVER *serve) {
 
        port = g_strdup_printf ("%d", serve->port);
        if (port == NULL)
-               return;
+               return 0;
 
        e = getaddrinfo(serve->listenaddr,port,&hints,&ai);
 
@@ -1709,21 +1819,7 @@ void setup_serve(SERVER *serve) {
        if ((serve->socket = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol)) < 0)
                err("socket: %m");
 
-       /* lose the pesky "Address already in use" error message */
-       if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
-               err("setsockopt SO_REUSEADDR");
-       }
-       if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
-               err("setsockopt SO_KEEPALIVE");
-       }
-
-       /* make the listening socket non-blocking */
-       if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
-               err("fcntl F_GETFL");
-       }
-       if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
-               err("fcntl F_SETFL O_NONBLOCK");
-       }
+       dosockopts(serve->socket);
 
        DEBUG("Waiting for connections... bind, ");
        e = bind(serve->socket, ai->ai_addr, ai->ai_addrlen);
@@ -1734,17 +1830,43 @@ void setup_serve(SERVER *serve) {
                err("listen: %m");
 
        freeaddrinfo (ai);
+       if(serve->servename) {
+               return 1;
+       } else {
+               return 0;
+       }
+}
 
-       sa.sa_handler = sigchld_handler;
-       sigemptyset(&sa.sa_mask);
-       sa.sa_flags = SA_RESTART;
-       if(sigaction(SIGCHLD, &sa, NULL) == -1)
-               err("sigaction: %m");
-       sa.sa_handler = sigterm_handler;
-       sigemptyset(&sa.sa_mask);
-       sa.sa_flags = SA_RESTART;
-       if(sigaction(SIGTERM, &sa, NULL) == -1)
-               err("sigaction: %m");
+void open_modern(void) {
+       struct addrinfo hints;
+       struct addrinfo* ai = NULL;
+       struct sock_flags;
+       int e;
+
+       memset(&hints, '\0', sizeof(hints));
+       hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
+       hints.ai_socktype = SOCK_STREAM;
+       hints.ai_family = AF_UNSPEC;
+       hints.ai_protocol = IPPROTO_TCP;
+       e = getaddrinfo(modern_listen, NBD_DEFAULT_PORT, &hints, &ai);
+       if(e != 0) {
+               fprintf(stderr, "getaddrinfo failed: %s\n", gai_strerror(e));
+               exit(EXIT_FAILURE);
+       }
+       if((modernsock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol))<0) {
+               err("socket: %m");
+       }
+
+       dosockopts(modernsock);
+
+       if(bind(modernsock, ai->ai_addr, ai->ai_addrlen)) {
+               err("bind: %m");
+       }
+       if(listen(modernsock, 10) <0) {
+               err("listen: %m");
+       }
+
+       freeaddrinfo(ai);
 }
 
 /**
@@ -1752,11 +1874,27 @@ void setup_serve(SERVER *serve) {
  **/
 void setup_servers(GArray* servers) {
        int i;
+       struct sigaction sa;
+       int want_modern=0;
 
        for(i=0;i<servers->len;i++) {
-               setup_serve(&(g_array_index(servers, SERVER, i)));
+               want_modern |= setup_serve(&(g_array_index(servers, SERVER, i)));
+       }
+       if(want_modern) {
+               open_modern();
        }
        children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
+
+       sa.sa_handler = sigchld_handler;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       if(sigaction(SIGCHLD, &sa, NULL) == -1)
+               err("sigaction: %m");
+       sa.sa_handler = sigterm_handler;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       if(sigaction(SIGTERM, &sa, NULL) == -1)
+               err("sigaction: %m");
 }
 
 /**