ncpfs: Pass unknown packets from server to userspace daemon. Now we can

deliver server messages to logged-in users even with UDP or TCP transport.

fs/ncpfs/inode.c

@@ -307,6 +307,7 @@ static const struct ncp_option ncp_opts[] = {
 	{ "flags",	OPT_INT,	'f' },
 	{ "wdogpid",	OPT_INT,	'w' },
 	{ "ncpfd",	OPT_INT,	'n' },
+	{ "infofd",	OPT_INT,	'i' },	/* v5 */
 	{ "version",	OPT_INT,	'v' },
 	{ NULL,		0,		0 } };
 
@@ -327,6 +328,7 @@ static int ncp_parse_options(struct ncp_mount_data_kernel *data, char *options)
 	data->gid = 0;
 	data->file_mode = 0600;
 	data->dir_mode = 0700;
+	data->info_fd = -1;
 	data->mounted_vol[0] = 0;
 	
 	while ((optval = ncp_getopt("ncpfs", &options, ncp_opts, NULL, &optarg, &optint)) != 0) {
@@ -363,11 +365,14 @@ static int ncp_parse_options(struct ncp_mount_data_kernel *data, char *options)
 			case 'n':
 				data->ncp_fd = optint;
 				break;
+			case 'i':
+				data->info_fd = optint;
+				break;
 			case 'v':
 				if (optint < NCP_MOUNT_VERSION_V4) {
 					return -ECHRNG;
 				}
-				if (optint > NCP_MOUNT_VERSION_V4) {
+				if (optint > NCP_MOUNT_VERSION_V5) {
 					return -ECHRNG;
 				}
 				version = optint;
@@ -418,6 +423,7 @@ static int ncp_fill_super(struct super_block *sb, void *raw_data, int silent)
 				data.gid = md->gid;
 				data.file_mode = md->file_mode;
 				data.dir_mode = md->dir_mode;
+				data.info_fd = -1;
 				memcpy(data.mounted_vol, md->mounted_vol,
 					NCP_VOLNAME_LEN+1);
 			}
@@ -437,6 +443,7 @@ static int ncp_fill_super(struct super_block *sb, void *raw_data, int silent)
 				data.gid = md->gid;
 				data.file_mode = md->file_mode;
 				data.dir_mode = md->dir_mode;
+				data.info_fd = -1;
 				data.mounted_vol[0] = 0;
 			}
 			break;
@@ -478,6 +485,26 @@ static int ncp_fill_super(struct super_block *sb, void *raw_data, int silent)
 	server->ncp_filp = ncp_filp;
 	server->ncp_sock = sock;
 	
+	if (data.info_fd != -1) {
+		struct socket *info_sock;
+
+		error = -EBADF;
+		server->info_filp = fget(data.info_fd);
+		if (!server->info_filp)
+			goto out_fput;
+		error = -ENOTSOCK;
+		sock_inode = server->info_filp->f_dentry->d_inode;
+		if (!S_ISSOCK(sock_inode->i_mode))
+			goto out_fput2;
+		info_sock = SOCKET_I(sock_inode);
+		if (!info_sock)
+			goto out_fput2;
+		error = -EBADFD;
+		if (info_sock->type != SOCK_STREAM)
+			goto out_fput2;
+		server->info_sock = info_sock;
+	}
+
 /*	server->lock = 0;	*/
 	init_MUTEX(&server->sem);
 	server->packet = NULL;
@@ -630,6 +657,9 @@ static int ncp_fill_super(struct super_block *sb, void *raw_data, int silent)
 	unload_nls(server->nls_io);
 	unload_nls(server->nls_vol);
 #endif
+out_fput2:
+	if (server->info_filp)
+		fput(server->info_filp);
 out_fput:
 	/* 23/12/1998 Marcin Dalecki <dalecki@cs.net.pl>:
 	 * 
@@ -667,6 +697,8 @@ static void ncp_put_super(struct super_block *sb)
 	}
 #endif /* CONFIG_NCPFS_NLS */
 
+	if (server->info_filp)
+		fput(server->info_filp);
 	fput(server->ncp_filp);
 	kill_proc(server->m.wdog_pid, SIGTERM, 1);
 

fs/ncpfs/sock.c

@@ -336,6 +336,31 @@ static void __ncp_next_request(struct ncp_server *server) {
 	__ncp_start_request(server, req);
 }
 
+static void info_server(struct ncp_server *server, unsigned int id, const void * data, size_t len) {
+	if (server->info_sock) {
+		struct iovec iov[2];
+		struct msghdr msg;
+		__u32 hdr[2];
+	
+		hdr[0] = cpu_to_be32(len + 8);
+		hdr[1] = cpu_to_be32(id);
+	
+		iov[0].iov_base = hdr;
+		iov[0].iov_len = 8;
+		iov[1].iov_base = (void *) data;
+		iov[1].iov_len = len;
+
+		msg.msg_name = NULL;
+		msg.msg_namelen = 0;
+		msg.msg_control = NULL;
+		msg.msg_iov = iov;
+		msg.msg_iovlen = 2;
+		msg.msg_flags = MSG_NOSIGNAL;
+
+		sock_sendmsg(server->info_sock, &msg, len + 8);
+	}
+}
+
 static void __ncpdgram_rcv_proc(void *s) {
 	struct ncp_server *server = s;
 	struct socket* sock;
@@ -376,6 +401,14 @@ static void __ncpdgram_rcv_proc(void *s) {
 				_send(sock, buf, sizeof(buf));
 				continue;
 			}
+			if (reply.type != NCP_POSITIVE_ACK && reply.type != NCP_REPLY) {
+				result = _recv(sock, server->unexpected_packet.data, sizeof(server->unexpected_packet.data), MSG_DONTWAIT);
+				if (result < 0) {
+					continue;
+				}
+				info_server(server, 0, server->unexpected_packet.data, result);
+				continue;
+			}
 			down(&server->rcv.creq_sem);		
 			req = server->rcv.creq;
 			if (req && (req->tx_type == NCP_ALLOC_SLOT_REQUEST || (server->sequence == reply.sequence && 
@@ -556,6 +589,15 @@ static int __ncptcp_rcv_proc(struct ncp_server *server) {
 				type = ntohs(server->rcv.buf.type);
 cont:;				
 				if (type != NCP_REPLY) {
+					if (datalen - 8 <= sizeof(server->unexpected_packet.data)) {
+						*(__u16*)(server->unexpected_packet.data) = htons(type);
+						server->unexpected_packet.len = datalen - 8;
+
+						server->rcv.state = 5;
+						server->rcv.ptr = server->unexpected_packet.data + 2;
+						server->rcv.len = datalen - 10;
+						break;
+					}					
 					DPRINTK("ncpfs: tcp: Unexpected NCP type %02X\n", type);
 skipdata2:;
 					server->rcv.state = 2;
@@ -613,6 +655,7 @@ skipdata:;
 			nextreq:;
 				__ncp_next_request(server);
 			case 2:
+			next:;
 				server->rcv.ptr = (unsigned char*)&server->rcv.buf;
 				server->rcv.len = 10;
 				server->rcv.state = 0;
@@ -620,6 +663,9 @@ skipdata:;
 			case 3:
 				ncp_finish_request(server->rcv.creq, -EIO);
 				goto nextreq;
+			case 5:
+				info_server(server, 0, server->unexpected_packet.data, server->unexpected_packet.len);
+				goto next;
 		}
 	}
 }

include/linux/ncp_fs_sb.h

@@ -27,6 +27,8 @@ struct ncp_server {
 
 	struct file *ncp_filp;	/* File pointer to ncp socket */
 	struct socket *ncp_sock;/* ncp socket */
+	struct file *info_filp;
+	struct socket *info_sock;
 
 	u8 sequence;
 	u8 task;
@@ -115,6 +117,10 @@ struct ncp_server {
 	struct tq_struct timeout_tq;		/* DGRAM only: associated queue, we run timers from process context */
 	int timeout_last;			/* DGRAM only: current timeout length */
 	int timeout_retries;			/* DGRAM only: retries left */
+	struct {
+		size_t len;
+		__u8 data[128];
+	} unexpected_packet;
 };
 
 extern void ncp_tcp_rcv_proc(void *server);

include/linux/ncp_mount.h

@@ -66,6 +66,8 @@ struct ncp_mount_data_v4 {
 	unsigned long dir_mode;
 };
 
+#define NCP_MOUNT_VERSION_V5	(5)	/* Text only */
+
 #ifdef __KERNEL__
 
 struct ncp_mount_data_kernel {
@@ -83,6 +85,7 @@ struct ncp_mount_data_kernel {
 	__kernel_gid32_t gid;
 	__kernel_mode_t  file_mode;
 	__kernel_mode_t  dir_mode;
+	int		 info_fd;
 };
 
 #endif /* __KERNEL__ */