Improve error handling
[nbd.git] / nbd-server.c
index 044e6d9..bc390ab 100644 (file)
@@ -172,6 +172,7 @@ typedef struct {
        gchar* exportname;    /**< (unprocessed) filename of the file we're exporting */
        off_t expected_size; /**< size of the exported file as it was told to
                               us through configuration */
+       gchar* listenaddr;   /**< The IP address we're listening on */
        unsigned int port;   /**< port we're exporting this file at */
        char* authname;      /**< filename of the authorization file */
        int flags;           /**< flags associated with this exported file */
@@ -334,7 +335,7 @@ inline void writeit(int f, void *buf, size_t len) {
  */
 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] [-C configuration file] [-p PID file name] [-o section name]\n"
+       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"
               "\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"
@@ -345,7 +346,8 @@ void usage() {
               "\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"
               "\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" );
+              "\t\taddress of the machine trying to connect\n" 
+              "\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");
        printf("Using configuration file %s\n", CFILE);
 }
 
@@ -353,6 +355,7 @@ void usage() {
 void dump_section(SERVER* serve, gchar* section_header) {
        printf("[%s]\n", section_header);
        printf("\texportname = %s\n", serve->exportname);
+       printf("\tlistenaddr = %s\n", serve->listenaddr);
        printf("\tport = %d\n", serve->port);
        if(serve->flags & F_READONLY) {
                printf("\treadonly = true\n");
@@ -364,7 +367,7 @@ void dump_section(SERVER* serve, gchar* section_header) {
                printf("\tcopyonwrite = true\n");
        }
        if(serve->expected_size) {
-               printf("\tfilesize = %Ld\n", (long long int)serve->expected_size);
+               printf("\tfilesize = %lld\n", (long long int)serve->expected_size);
        }
        if(serve->authname) {
                printf("\tauthfile = %s\n", serve->authname);
@@ -401,7 +404,8 @@ SERVER* cmdline(int argc, char *argv[]) {
        size_t last;
        char suffix;
        gboolean do_output=FALSE;
-       gchar* section_header;
+       gchar* section_header="";
+       gchar** addr_port;
 
        if(argc==1) {
                return NULL;
@@ -415,7 +419,15 @@ SERVER* cmdline(int argc, char *argv[]) {
                        /* non-option argument */
                        switch(nonspecial++) {
                        case 0:
-                               serve->port=strtol(optarg, NULL, 0);
+                               addr_port=g_strsplit(optarg, ":", 2);
+                               if(addr_port[1]) {
+                                       serve->port=strtol(addr_port[1], NULL, 0);
+                                       serve->listenaddr=g_strdup(addr_port[0]);
+                               } else {
+                                       serve->listenaddr=g_strdup("0.0.0.0");
+                                       serve->port=strtol(addr_port[0], NULL, 0);
+                               }
+                               g_strfreev(addr_port);
                                break;
                        case 1:
                                serve->exportname = g_strdup(optarg);
@@ -543,17 +555,17 @@ GArray* parse_cfile(gchar* f, GError** e) {
                { "readonly",   FALSE,  PARAM_BOOL,     NULL, F_READONLY },
                { "multifile",  FALSE,  PARAM_BOOL,     NULL, F_MULTIFILE },
                { "copyonwrite", FALSE, PARAM_BOOL,     NULL, F_COPYONWRITE },
-               { "autoreadonly", FALSE, PARAM_BOOL,    NULL, F_AUTOREADONLY },
                { "sparse_cow", FALSE,  PARAM_BOOL,     NULL, F_SPARSE },
                { "sdp",        FALSE,  PARAM_BOOL,     NULL, F_SDP },
+               { "listenaddr", FALSE,  PARAM_STRING,   NULL, 0 },
        };
-       const int lp_size=14;
+       const int lp_size=sizeof(lp)/sizeof(PARAM);
        PARAM gp[] = {
                { "user",       FALSE, PARAM_STRING,    &runuser,       0 },
                { "group",      FALSE, PARAM_STRING,    &rungroup,      0 },
        };
        PARAM* p=gp;
-       int p_size=2;
+       int p_size=sizeof(gp)/sizeof(PARAM);
        GKeyFile *cfile;
        GError *err = NULL;
        const char *err_msg=NULL;
@@ -561,6 +573,7 @@ GArray* parse_cfile(gchar* f, GError** e) {
        GArray *retval=NULL;
        gchar **groups;
        gboolean value;
+       gchar* startgroup;
        gint i;
        gint j;
 
@@ -573,7 +586,8 @@ GArray* parse_cfile(gchar* f, GError** e) {
                g_key_file_free(cfile);
                return retval;
        }
-       if(strcmp(g_key_file_get_start_group(cfile), "generic")) {
+       startgroup = g_key_file_get_start_group(cfile);
+       if(!startgroup || strcmp(startgroup, "generic")) {
                g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
                g_key_file_free(cfile);
                return NULL;
@@ -590,8 +604,8 @@ GArray* parse_cfile(gchar* f, GError** e) {
                lp[6].target=&(s.prerun);
                lp[7].target=&(s.postrun);
                lp[8].target=lp[9].target=lp[10].target=
-                               lp[11].target=lp[12].target=
-                               lp[13].target=&(s.flags);
+                               lp[11].target=lp[12].target=&(s.flags);
+               lp[13].target=&(s.listenaddr);
 
                /* After the [generic] group, start parsing exports */
                if(i==1) {
@@ -677,6 +691,9 @@ GArray* parse_cfile(gchar* f, GError** e) {
                virtstyle=NULL;
                /* Don't append values for the [generic] group */
                if(i>0) {
+                       if(!s.listenaddr) {
+                               s.listenaddr = g_strdup("0.0.0.0");
+                       }
                        g_array_append_val(retval, s);
                }
 #ifndef WITH_SDP
@@ -745,7 +762,7 @@ void sigterm_handler(int s) {
                unlink(pidfname);
        }
 
-       exit(0);
+       exit(EXIT_SUCCESS);
 }
 
 /**
@@ -877,7 +894,7 @@ ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
        if(maxbytes && len > maxbytes)
                len = maxbytes;
 
-       DEBUG4("(WRITE to fd %d offset %Lu len %u), ", fhandle, foffset, len);
+       DEBUG4("(WRITE to fd %d offset %llu len %u), ", fhandle, foffset, len);
 
        myseek(fhandle, foffset);
        return write(fhandle, buf, len);
@@ -888,7 +905,7 @@ ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
  * @return 0 on success, nonzero on failure
  **/
 int rawexpwrite_fully(off_t a, char *buf, size_t len, CLIENT *client) {
-       ssize_t ret;
+       ssize_t ret=0;
 
        while(len > 0 && (ret=rawexpwrite(a, buf, len, client)) > 0 ) {
                a += ret;
@@ -919,7 +936,7 @@ ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
        if(maxbytes && len > maxbytes)
                len = maxbytes;
 
-       DEBUG4("(READ from fd %d offset %Lu len %u), ", fhandle, foffset, len);
+       DEBUG4("(READ from fd %d offset %llu len %u), ", fhandle, foffset, len);
 
        myseek(fhandle, foffset);
        return read(fhandle, buf, len);
@@ -930,7 +947,7 @@ ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
  * @return 0 on success, nonzero on failure
  **/
 int rawexpread_fully(off_t a, char *buf, size_t len, CLIENT *client) {
-       ssize_t ret;
+       ssize_t ret=0;
 
        while(len > 0 && (ret=rawexpread(a, buf, len, client)) > 0 ) {
                a += ret;
@@ -956,7 +973,7 @@ int expread(off_t a, char *buf, size_t len, CLIENT *client) {
 
        if (!(client->server->flags & F_COPYONWRITE))
                return(rawexpread_fully(a, buf, len, client));
-       DEBUG3("Asked to read %d bytes at %Lu.\n", len, (unsigned long long)a);
+       DEBUG3("Asked to read %d bytes at %llu.\n", len, (unsigned long long)a);
 
        mapl=a/DIFFPAGESIZE; maph=(a+len-1)/DIFFPAGESIZE;
 
@@ -966,12 +983,12 @@ int expread(off_t a, char *buf, size_t len, CLIENT *client) {
                rdlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
                        len : (size_t)DIFFPAGESIZE-offset;
                if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
-                       DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
+                       DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt]));
                        myseek(client->difffile, client->difmap[mapcnt]*DIFFPAGESIZE+offset);
                        if (read(client->difffile, buf, rdlen) != rdlen) return -1;
                } else { /* the block is not there */
-                       DEBUG2("Page %Lu is not here, we read the original one\n",
+                       DEBUG2("Page %llu is not here, we read the original one\n",
                               (unsigned long long)mapcnt);
                        if(rawexpread_fully(a, buf, rdlen, client)) return -1;
                }
@@ -1000,7 +1017,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
 
        if (!(client->server->flags & F_COPYONWRITE))
                return(rawexpwrite_fully(a, buf, len, client)); 
-       DEBUG3("Asked to write %d bytes at %Lu.\n", len, (unsigned long long)a);
+       DEBUG3("Asked to write %d bytes at %llu.\n", len, (unsigned long long)a);
 
        mapl=a/DIFFPAGESIZE ; maph=(a+len-1)/DIFFPAGESIZE ;
 
@@ -1011,7 +1028,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
                        len : (size_t)DIFFPAGESIZE-offset;
 
                if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
-                       DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
+                       DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt])) ;
                        myseek(client->difffile,
                                        client->difmap[mapcnt]*DIFFPAGESIZE+offset);
@@ -1019,7 +1036,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
                } else { /* the block is not there */
                        myseek(client->difffile,client->difffilelen*DIFFPAGESIZE) ;
                        client->difmap[mapcnt]=(client->server->flags&F_SPARSE)?mapcnt:client->difffilelen++;
-                       DEBUG3("Page %Lu is not here, we put it at %lu\n",
+                       DEBUG3("Page %llu is not here, we put it at %lu\n",
                               (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt]));
                        rdlen=DIFFPAGESIZE ;
@@ -1119,7 +1136,7 @@ int mainloop(CLIENT *client) {
                if (len > BUFSIZE + sizeof(struct nbd_reply))
                        err("Request too big!");
 #ifdef DODBG
-               printf("%s from %Lu (%Lu) len %d, ", request.type ? "WRITE" :
+               printf("%s from %llu (%llu) len %d, ", request.type ? "WRITE" :
                                "READ", (unsigned long long)request.from,
                                (unsigned long long)request.from / 512, len);
 #endif
@@ -1203,8 +1220,12 @@ void setupexport(CLIENT* client) {
                        /* Try again because maybe media was read-only */
                        fi.fhandle = open(tmpname, O_RDONLY);
                        if(fi.fhandle != -1) {
-                               client->server->flags |= F_AUTOREADONLY;
-                               client->server->flags |= F_READONLY;
+                               /* Opening the base file in copyonwrite mode is
+                                * okay */
+                               if(!(client->server->flags & F_COPYONWRITE)) {
+                                       client->server->flags |= F_AUTOREADONLY;
+                                       client->server->flags |= F_READONLY;
+                               }
                        }
                }
                if(fi.fhandle == -1) {
@@ -1238,7 +1259,7 @@ void setupexport(CLIENT* client) {
                client->exportsize = client->server->expected_size;
        }
 
-       msg3(LOG_INFO, "Size of exported file/device is %Lu", (unsigned long long)client->exportsize);
+       msg3(LOG_INFO, "Size of exported file/device is %llu", (unsigned long long)client->exportsize);
        if(multifile) {
                msg3(LOG_INFO, "Total number of files: %d", i);
        }
@@ -1367,7 +1388,7 @@ void destroy_pid_t(gpointer data) {
 /**
  * Loop through the available servers, and serve them. Never returns.
  **/
-int serveloop(GArray* servers) G_GNUC_NORETURN {
+int serveloop(GArray* servers) {
        struct sockaddr_in addrin;
        socklen_t addrinlen=sizeof(addrin);
        SERVER *serve;
@@ -1376,7 +1397,6 @@ int serveloop(GArray* servers) G_GNUC_NORETURN {
        int sock;
        fd_set mset;
        fd_set rset;
-       struct timeval tv;
 
        /* 
         * Set up the master fd_set. The set of descriptors we need
@@ -1398,16 +1418,21 @@ int serveloop(GArray* servers) G_GNUC_NORETURN {
                pid_t *pid;
 
                memcpy(&rset, &mset, sizeof(fd_set));
-               tv.tv_sec=0;
-               tv.tv_usec=500;
-               if(select(max+1, &rset, NULL, NULL, &tv)>0) {
+               if(select(max+1, &rset, NULL, NULL, NULL)>0) {
                        DEBUG("accept, ");
                        for(i=0;i<servers->len;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((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));
                                        client->server=serve;
                                        client->exportsize=OFFT_MAX;
@@ -1434,7 +1459,7 @@ int serveloop(GArray* servers) G_GNUC_NORETURN {
                                        /* child */
                                        g_hash_table_destroy(children);
                                        for(i=0;i<servers->len;i++) {
-                                               serve=g_array_index(servers, SERVER*, i);
+                                               serve=&g_array_index(servers, SERVER, i);
                                                close(serve->socket);
                                        }
                                        /* FALSE does not free the
@@ -1455,55 +1480,6 @@ int serveloop(GArray* servers) G_GNUC_NORETURN {
 }
 
 /**
- * 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. This parameter
- *     is only used to create a PID file of the form
- *     /var/run/nbd-server.&lt;port&gt;.pid; it's not modified in any way.
- **/
-#if !defined(NODAEMON) && !defined(NOFORK)
-void daemonize(SERVER* serve) {
-       FILE*pidf;
-
-       if(serve && !(serve->port)) {
-               return;
-       }
-       if(daemon(0,0)<0) {
-               err("daemon");
-       }
-       if(!*pidftemplate) {
-               if(serve) {
-                       strncpy(pidftemplate, "/var/run/server.%d.pid", 255);
-               } else {
-                       strncpy(pidftemplate, "/var/run/server.pid", 255);
-               }
-       }
-       snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
-       pidf=fopen(pidfname, "w");
-       if(pidf) {
-               fprintf(pidf,"%d\n", (int)getpid());
-               fclose(pidf);
-       } else {
-               perror("fopen");
-               fprintf(stderr, "Not fatal; continuing");
-       }
-}
-#else
-#define daemonize(serve)
-#endif /* !defined(NODAEMON) && !defined(NOFORK) */
-
-/*
- * Everything beyond this point (in the file) is run in non-daemon mode.
- * The stuff above daemonize() isn't.
- */
-
-void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN {
-       g_message("Export of %s on port %d failed:", serve->exportname,
-                       serve->port);
-       err(msg);
-}
-
-/**
  * Connect a server's socket.
  *
  * @param serve the server we want to connect.
@@ -1553,7 +1529,8 @@ void setup_serve(SERVER *serve) {
        }
 #endif
        addrin.sin_port = htons(serve->port);
-       addrin.sin_addr.s_addr = 0;
+       if(!inet_aton(serve->listenaddr, &(addrin.sin_addr)))
+               err("could not parse listen address");
        if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
                err("bind: %m");
        DEBUG("listen, ");
@@ -1584,6 +1561,57 @@ void setup_servers(GArray* servers) {
 }
 
 /**
+ * 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. This parameter
+ *     is only used to create a PID file of the form
+ *     /var/run/nbd-server.&lt;port&gt;.pid; it's not modified in any way.
+ **/
+#if !defined(NODAEMON) && !defined(NOFORK)
+void daemonize(SERVER* serve) {
+       FILE*pidf;
+
+       if(serve && !(serve->port)) {
+               return;
+       }
+       if(daemon(0,0)<0) {
+               err("daemon");
+       }
+       if(!*pidftemplate) {
+               if(serve) {
+                       strncpy(pidftemplate, "/var/run/nbd-server.%d.pid", 255);
+               } else {
+                       strncpy(pidftemplate, "/var/run/nbd-server.pid", 255);
+               }
+       }
+       snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
+       pidf=fopen(pidfname, "w");
+       if(pidf) {
+               fprintf(pidf,"%d\n", (int)getpid());
+               fclose(pidf);
+       } else {
+               perror("fopen");
+               fprintf(stderr, "Not fatal; continuing");
+       }
+}
+#else
+#define daemonize(serve)
+#endif /* !defined(NODAEMON) && !defined(NOFORK) */
+
+/*
+ * Everything beyond this point (in the file) is run in non-daemon mode.
+ * The stuff above daemonize() isn't.
+ */
+
+void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN;
+
+void serve_err(SERVER* serve, const char* msg) {
+       g_message("Export of %s on port %d failed:", serve->exportname,
+                       serve->port);
+       err(msg);
+}
+
+/**
  * Set up user-ID and/or group-ID
  **/
 void dousers(void) {
@@ -1595,8 +1623,10 @@ void dousers(void) {
                        g_message("Invalid group name: %s", rungroup);
                        exit(EXIT_FAILURE);
                }
-               if(setgid(gr->gr_gid)<0)
-                       msg3(LOG_DEBUG, "Could not set GID: %s", strerror(errno));
+               if(setgid(gr->gr_gid)<0) {
+                       g_message("Could not set GID: %s", strerror(errno));
+                       exit(EXIT_FAILURE);
+               }
        }
        if(runuser) {
                pw=getpwnam(runuser);
@@ -1604,8 +1634,10 @@ void dousers(void) {
                        g_message("Invalid user name: %s", runuser);
                        exit(EXIT_FAILURE);
                }
-               if(setuid(pw->pw_uid)<0)
-                       msg3(LOG_DEBUG, "Could not set UID: %s", strerror(errno));
+               if(setuid(pw->pw_uid)<0) {
+                       g_message("Could not set UID: %s", strerror(errno));
+                       exit(EXIT_FAILURE);
+               }
        }
 }
 
@@ -1619,7 +1651,7 @@ int main(int argc, char *argv[]) {
 
        if (sizeof( struct nbd_request )!=28) {
                fprintf(stderr,"Bad size of structure. Alignment problems?\n");
-               exit(-1) ;
+               exit(EXIT_FAILURE) ;
        }
 
        memset(pidftemplate, '\0', 256);