kinit/nfsmount/mount.c

#include <sys/mount.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <linux/nfs.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include "nfsmount.h"
#include "sunrpc.h"

static uint32_t mount_port;

struct mount_call {
	struct rpc_call rpc;
	uint32_t path_len;
	char path[0];
};

/*
 * The following structure is the NFS v3 on-the-wire file handle,
 * as defined in rfc1813.
 * This differs from the structure used by the kernel,
 * defined in <linux/nfh3.h>: rfc has a long in network order,
 * kernel has a short in native order.
 * Both kernel and rfc use the name nfs_fh; kernel name is
 * visible to user apps in some versions of libc.
 * Use different name to avoid clashes.
 */
#define NFS_MAXFHSIZE_WIRE 64
struct nfs_fh_wire {
	uint32_t size;
	char data[NFS_MAXFHSIZE_WIRE];
} __attribute__ ((packed));

struct mount_reply {
	struct rpc_reply reply;
	uint32_t status;
	struct nfs_fh_wire fh;
} __attribute__ ((packed));

#define MNT_REPLY_MINSIZE (sizeof(struct rpc_reply) + sizeof(uint32_t))

#ifndef MNTPROC_MNT
#  define MNTPROC_MNT	1
#  define MNTPROC_UMNT	3
#endif /* MNTPROC_MNT */

static int get_ports(uint32_t server, const struct nfs_mount_data *data)
{
	uint32_t nfs_ver, mount_ver;
	uint32_t proto;

	if (data->flags & NFS_MOUNT_VER3) {
		nfs_ver = NFS3_VERSION;
		mount_ver = NFS_MNT3_VERSION;
	} else {
		nfs_ver = NFS2_VERSION;
		mount_ver = NFS_MNT_VERSION;
	}

	proto = (data->flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP;

	if (nfs_port == 0) {
		nfs_port = portmap(server, NFS_PROGRAM, nfs_ver, proto);
		if (nfs_port == 0) {
			if (proto == IPPROTO_TCP) {
				struct in_addr addr = { server };
				fprintf(stderr, "NFS over TCP not "
					"available from %s\n", inet_ntoa(addr));
				return -1;
			}
			nfs_port = NFS_PORT;
		}
	}

	if (mount_port == 0) {
		mount_port = portmap(server, NFS_MNT_PROGRAM, mount_ver, proto);
		if (mount_port == 0)
			mount_port = MOUNT_PORT;
	}
	return 0;
}

static inline int pad_len(int len)
{
	return (len + 3) & ~3;
}

static inline void dump_params(uint32_t server,
			       const char *path,
			       const struct nfs_mount_data *data)
{
	(void)server;
	(void)path;
	(void)data;

#ifdef NFS_DEBUG
	struct in_addr addr = { server };

	printf("NFS params:\n");
	printf("  server = %s, path = \"%s\", ", inet_ntoa(addr), path);
	printf("version = %d, proto = %s\n",
	       data->flags & NFS_MOUNT_VER3 ? 3 : 2,
	       (data->flags & NFS_MOUNT_TCP) ? "tcp" : "udp");
	printf("  mount_port = %d, nfs_port = %d, flags = %08x\n",
	       mount_port, nfs_port, data->flags);
	printf("  rsize = %d, wsize = %d, timeo = %d, retrans = %d\n",
	       data->rsize, data->wsize, data->timeo, data->retrans);
	printf("  acreg (min, max) = (%d, %d), acdir (min, max) = (%d, %d)\n",
	       data->acregmin, data->acregmax, data->acdirmin, data->acdirmax);
	printf("  soft = %d, intr = %d, posix = %d, nocto = %d, noac = %d\n",
	       (data->flags & NFS_MOUNT_SOFT) != 0,
	       (data->flags & NFS_MOUNT_INTR) != 0,
	       (data->flags & NFS_MOUNT_POSIX) != 0,
	       (data->flags & NFS_MOUNT_NOCTO) != 0,
	       (data->flags & NFS_MOUNT_NOAC) != 0);
#endif
}

static inline void dump_fh(const char *data, int len)
{
	(void)data;
	(void)len;

#ifdef NFS_DEBUG
	int i = 0;
	int max = len - (len % 8);

	printf("Root file handle: %d bytes\n", NFS2_FHSIZE);

	while (i < max) {
		int j;

		printf("  %4d:  ", i);
		for (j = 0; j < 4; j++) {
			printf("%02x %02x %02x %02x  ",
			       data[i] & 0xff, data[i + 1] & 0xff,
			       data[i + 2] & 0xff, data[i + 3] & 0xff);
		}
		i += j;
		printf("\n");
	}
#endif
}

static struct mount_reply mnt_reply;

static int mount_call(uint32_t proc, uint32_t version,
		      const char *path, struct client *clnt)
{
	struct mount_call *mnt_call = NULL;
	size_t path_len, call_len;
	struct rpc rpc;
	int ret = 0;

	path_len = strlen(path);
	call_len = sizeof(*mnt_call) + pad_len(path_len);

	if ((mnt_call = malloc(call_len)) == NULL) {
		perror("malloc");
		goto bail;
	}

	memset(mnt_call, 0, sizeof(*mnt_call));

	mnt_call->rpc.program = htonl(NFS_MNT_PROGRAM);
	mnt_call->rpc.prog_vers = htonl(version);
	mnt_call->rpc.proc = htonl(proc);
	mnt_call->path_len = htonl(path_len);
	memcpy(mnt_call->path, path, path_len);

	rpc.call = (struct rpc_call *)mnt_call;
	rpc.call_len = call_len;
	rpc.reply = (struct rpc_reply *)&mnt_reply;
	rpc.reply_len = sizeof(mnt_reply);

	if (rpc_call(clnt, &rpc) < 0)
		goto bail;

	if (proc != MNTPROC_MNT) {
		goto done;
	}

	if (rpc.reply_len < MNT_REPLY_MINSIZE) {
		fprintf(stderr, "incomplete reply: %zu < %zu\n",
			rpc.reply_len, MNT_REPLY_MINSIZE);
		goto bail;
	}

	if (mnt_reply.status != 0) {
		fprintf(stderr, "mount call failed - server replied: %s.\n",
			strerror(ntohl(mnt_reply.status)));
		goto bail;
	}

	goto done;

bail:
	ret = -1;

done:
	if (mnt_call) {
		free(mnt_call);
	}

	return ret;
}

static int mount_v2(const char *path,
		    struct nfs_mount_data *data, struct client *clnt)
{
	int ret = mount_call(MNTPROC_MNT, NFS_MNT_VERSION, path, clnt);

	if (ret == 0) {
		dump_fh((const char *)&mnt_reply.fh, NFS2_FHSIZE);

		data->root.size = NFS_FHSIZE;
		memcpy(data->root.data, &mnt_reply.fh, NFS_FHSIZE);
		memcpy(data->old_root.data, &mnt_reply.fh, NFS_FHSIZE);
	}

	return ret;
}

static inline int umount_v2(const char *path, struct client *clnt)
{
	return mount_call(MNTPROC_UMNT, NFS_MNT_VERSION, path, clnt);
}

static int mount_v3(const char *path,
		    struct nfs_mount_data *data, struct client *clnt)
{
	int ret = mount_call(MNTPROC_MNT, NFS_MNT3_VERSION, path, clnt);

	if (ret == 0) {
		size_t fhsize = ntohl(mnt_reply.fh.size);

		dump_fh((const char *)&mnt_reply.fh.data, fhsize);

		memset(data->old_root.data, 0, NFS_FHSIZE);
		memset(&data->root, 0, sizeof(data->root));
		data->root.size = fhsize;
		memcpy(&data->root.data, mnt_reply.fh.data, fhsize);
		data->flags |= NFS_MOUNT_VER3;
	}

	return ret;
}

static inline int umount_v3(const char *path, struct client *clnt)
{
	return mount_call(MNTPROC_UMNT, NFS_MNT3_VERSION, path, clnt);
}

int nfs_mount(const char *pathname, const char *hostname,
	      uint32_t server, const char *rem_path, const char *path,
	      struct nfs_mount_data *data)
{
	struct client *clnt = NULL;
	struct sockaddr_in addr;
	char mounted = 0;
	int sock = -1;
	int ret = 0;
	int mountflags;

	if (get_ports(server, data) != 0) {
		goto bail;
	}

	dump_params(server, rem_path, data);

	if (data->flags & NFS_MOUNT_TCP) {
		clnt = tcp_client(server, mount_port, CLI_RESVPORT);
	} else {
		clnt = udp_client(server, mount_port, CLI_RESVPORT);
	}

	if (clnt == NULL) {
		goto bail;
	}

	if (data->flags & NFS_MOUNT_VER3) {
		ret = mount_v3(rem_path, data, clnt);
	} else {
		ret = mount_v2(rem_path, data, clnt);
	}

	if (ret == -1) {
		goto bail;
	}
	mounted = 1;

	if (data->flags & NFS_MOUNT_TCP) {
		sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
	} else {
		sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
	}

	if (sock == -1) {
		perror("socket");
		goto bail;
	}

	if (bindresvport(sock, 0) == -1) {
		perror("bindresvport");
		goto bail;
	}

	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr = server;
	addr.sin_port = htons(nfs_port);
	memcpy(&data->addr, &addr, sizeof(data->addr));

	strncpy(data->hostname, hostname, sizeof(data->hostname));

	data->fd = sock;

	mountflags = (data->flags & NFS_MOUNT_KLIBC_RONLY) ? MS_RDONLY : 0;
	data->flags = data->flags & NFS_MOUNT_FLAGMASK;
	ret = mount(pathname, path, "nfs", mountflags, data);

	if (ret == -1) {
		if (errno == ENODEV) {
			fprintf(stderr, "mount: the kernel lacks NFS v%d "
				"support\n",
				(data->flags & NFS_MOUNT_VER3) ? 3 : 2);
		} else {
			perror("mount");
		}
		goto bail;
	}

	DEBUG(("Mounted %s on %s\n", pathname, path));

	goto done;

      bail:
	if (mounted) {
		if (data->flags & NFS_MOUNT_VER3) {
			umount_v3(path, clnt);
		} else {
			umount_v2(path, clnt);
		}
	}

	ret = -1;

      done:
	if (clnt) {
		client_free(clnt);
	}

	if (sock != -1) {
		close(sock);
	}

	return ret;
}
1	#include <sys/mount.h>
2	#include <sys/types.h>
3	#include <sys/socket.h>
4	#include <arpa/inet.h>
5	#include <netinet/in.h>
6	#include <linux/nfs.h>
7	#include <stdio.h>
8	#include <stdlib.h>
9	#include <string.h>
10	#include <errno.h>
11
12	#include "nfsmount.h"
13	#include "sunrpc.h"
14
15	static uint32_t mount_port;
16
17	struct mount_call {
18	struct rpc_call rpc;
19	uint32_t path_len;
20	char path[0];
21	};
22
23	/*
24	* The following structure is the NFS v3 on-the-wire file handle,
25	* as defined in rfc1813.
26	* This differs from the structure used by the kernel,
27	* defined in <linux/nfh3.h>: rfc has a long in network order,
28	* kernel has a short in native order.
29	* Both kernel and rfc use the name nfs_fh; kernel name is
30	* visible to user apps in some versions of libc.
31	* Use different name to avoid clashes.
32	*/
33	#define NFS_MAXFHSIZE_WIRE 64
34	struct nfs_fh_wire {
35	uint32_t size;
36	char data[NFS_MAXFHSIZE_WIRE];
37	} __attribute__ ((packed));
38
39	struct mount_reply {
40	struct rpc_reply reply;
41	uint32_t status;
42	struct nfs_fh_wire fh;
43	} __attribute__ ((packed));
44
45	#define MNT_REPLY_MINSIZE (sizeof(struct rpc_reply) + sizeof(uint32_t))
46
47	#ifndef MNTPROC_MNT
48	# define MNTPROC_MNT 1
49	# define MNTPROC_UMNT 3
50	#endif /* MNTPROC_MNT */
51
52	static int get_ports(uint32_t server, const struct nfs_mount_data *data)
53	{
54	uint32_t nfs_ver, mount_ver;
55	uint32_t proto;
56
57	if (data->flags & NFS_MOUNT_VER3) {
58	nfs_ver = NFS3_VERSION;
59	mount_ver = NFS_MNT3_VERSION;
60	} else {
61	nfs_ver = NFS2_VERSION;
62	mount_ver = NFS_MNT_VERSION;
63	}
64
65	proto = (data->flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP;
66
67	if (nfs_port == 0) {
68	nfs_port = portmap(server, NFS_PROGRAM, nfs_ver, proto);
69	if (nfs_port == 0) {
70	if (proto == IPPROTO_TCP) {
71	struct in_addr addr = { server };
72	fprintf(stderr, "NFS over TCP not "
73	"available from %s\n", inet_ntoa(addr));
74	return -1;
75	}
76	nfs_port = NFS_PORT;
77	}
78	}
79
80	if (mount_port == 0) {
81	mount_port = portmap(server, NFS_MNT_PROGRAM, mount_ver, proto);
82	if (mount_port == 0)
83	mount_port = MOUNT_PORT;
84	}
85	return 0;
86	}
87
88	static inline int pad_len(int len)
89	{
90	return (len + 3) & ~3;
91	}
92
93	static inline void dump_params(uint32_t server,
94	const char *path,
95	const struct nfs_mount_data *data)
96	{
97	(void)server;
98	(void)path;
99	(void)data;
100
101	#ifdef NFS_DEBUG
102	struct in_addr addr = { server };
103
104	printf("NFS params:\n");
105	printf(" server = %s, path = \"%s\", ", inet_ntoa(addr), path);
106	printf("version = %d, proto = %s\n",
107	data->flags & NFS_MOUNT_VER3 ? 3 : 2,
108	(data->flags & NFS_MOUNT_TCP) ? "tcp" : "udp");
109	printf(" mount_port = %d, nfs_port = %d, flags = %08x\n",
110	mount_port, nfs_port, data->flags);
111	printf(" rsize = %d, wsize = %d, timeo = %d, retrans = %d\n",
112	data->rsize, data->wsize, data->timeo, data->retrans);
113	printf(" acreg (min, max) = (%d, %d), acdir (min, max) = (%d, %d)\n",
114	data->acregmin, data->acregmax, data->acdirmin, data->acdirmax);
115	printf(" soft = %d, intr = %d, posix = %d, nocto = %d, noac = %d\n",
116	(data->flags & NFS_MOUNT_SOFT) != 0,
117	(data->flags & NFS_MOUNT_INTR) != 0,
118	(data->flags & NFS_MOUNT_POSIX) != 0,
119	(data->flags & NFS_MOUNT_NOCTO) != 0,
120	(data->flags & NFS_MOUNT_NOAC) != 0);
121	#endif
122	}
123
124	static inline void dump_fh(const char *data, int len)
125	{
126	(void)data;
127	(void)len;
128
129	#ifdef NFS_DEBUG
130	int i = 0;
131	int max = len - (len % 8);
132
133	printf("Root file handle: %d bytes\n", NFS2_FHSIZE);
134
135	while (i < max) {
136	int j;
137
138	printf(" %4d: ", i);
139	for (j = 0; j < 4; j++) {
140	printf("%02x %02x %02x %02x ",
141	data[i] & 0xff, data[i + 1] & 0xff,
142	data[i + 2] & 0xff, data[i + 3] & 0xff);
143	}
144	i += j;
145	printf("\n");
146	}
147	#endif
148	}
149
150	static struct mount_reply mnt_reply;
151
152	static int mount_call(uint32_t proc, uint32_t version,
153	const char path, struct client clnt)
154	{
155	struct mount_call *mnt_call = NULL;
156	size_t path_len, call_len;
157	struct rpc rpc;
158	int ret = 0;
159
160	path_len = strlen(path);
161	call_len = sizeof(*mnt_call) + pad_len(path_len);
162
163	if ((mnt_call = malloc(call_len)) == NULL) {
164	perror("malloc");
165	goto bail;
166	}
167
168	memset(mnt_call, 0, sizeof(*mnt_call));
169
170	mnt_call->rpc.program = htonl(NFS_MNT_PROGRAM);
171	mnt_call->rpc.prog_vers = htonl(version);
172	mnt_call->rpc.proc = htonl(proc);
173	mnt_call->path_len = htonl(path_len);
174	memcpy(mnt_call->path, path, path_len);
175
176	rpc.call = (struct rpc_call *)mnt_call;
177	rpc.call_len = call_len;
178	rpc.reply = (struct rpc_reply *)&mnt_reply;
179	rpc.reply_len = sizeof(mnt_reply);
180
181	if (rpc_call(clnt, &rpc) < 0)
182	goto bail;
183
184	if (proc != MNTPROC_MNT) {
185	goto done;
186	}
187
188	if (rpc.reply_len < MNT_REPLY_MINSIZE) {
189	fprintf(stderr, "incomplete reply: %zu < %zu\n",
190	rpc.reply_len, MNT_REPLY_MINSIZE);
191	goto bail;
192	}
193
194	if (mnt_reply.status != 0) {
195	fprintf(stderr, "mount call failed - server replied: %s.\n",
196	strerror(ntohl(mnt_reply.status)));
197	goto bail;
198	}
199
200	goto done;
201
202	bail:
203	ret = -1;
204
205	done:
206	if (mnt_call) {
207	free(mnt_call);
208	}
209
210	return ret;
211	}
212
213	static int mount_v2(const char *path,
214	struct nfs_mount_data data, struct client clnt)
215	{
216	int ret = mount_call(MNTPROC_MNT, NFS_MNT_VERSION, path, clnt);
217
218	if (ret == 0) {
219	dump_fh((const char *)&mnt_reply.fh, NFS2_FHSIZE);
220
221	data->root.size = NFS_FHSIZE;
222	memcpy(data->root.data, &mnt_reply.fh, NFS_FHSIZE);
223	memcpy(data->old_root.data, &mnt_reply.fh, NFS_FHSIZE);
224	}
225
226	return ret;
227	}
228
229	static inline int umount_v2(const char path, struct client clnt)
230	{
231	return mount_call(MNTPROC_UMNT, NFS_MNT_VERSION, path, clnt);
232	}
233
234	static int mount_v3(const char *path,
235	struct nfs_mount_data data, struct client clnt)
236	{
237	int ret = mount_call(MNTPROC_MNT, NFS_MNT3_VERSION, path, clnt);
238
239	if (ret == 0) {
240	size_t fhsize = ntohl(mnt_reply.fh.size);
241
242	dump_fh((const char *)&mnt_reply.fh.data, fhsize);
243
244	memset(data->old_root.data, 0, NFS_FHSIZE);
245	memset(&data->root, 0, sizeof(data->root));
246	data->root.size = fhsize;
247	memcpy(&data->root.data, mnt_reply.fh.data, fhsize);
248	data->flags \|= NFS_MOUNT_VER3;
249	}
250
251	return ret;
252	}
253
254	static inline int umount_v3(const char path, struct client clnt)
255	{
256	return mount_call(MNTPROC_UMNT, NFS_MNT3_VERSION, path, clnt);
257	}
258
259	int nfs_mount(const char pathname, const char hostname,
260	uint32_t server, const char rem_path, const char path,
261	struct nfs_mount_data *data)
262	{
263	struct client *clnt = NULL;
264	struct sockaddr_in addr;
265	char mounted = 0;
266	int sock = -1;
267	int ret = 0;
268	int mountflags;
269
270	if (get_ports(server, data) != 0) {
271	goto bail;
272	}
273
274	dump_params(server, rem_path, data);
275
276	if (data->flags & NFS_MOUNT_TCP) {
277	clnt = tcp_client(server, mount_port, CLI_RESVPORT);
278	} else {
279	clnt = udp_client(server, mount_port, CLI_RESVPORT);
280	}
281
282	if (clnt == NULL) {
283	goto bail;
284	}
285
286	if (data->flags & NFS_MOUNT_VER3) {
287	ret = mount_v3(rem_path, data, clnt);
288	} else {
289	ret = mount_v2(rem_path, data, clnt);
290	}
291
292	if (ret == -1) {
293	goto bail;
294	}
295	mounted = 1;
296
297	if (data->flags & NFS_MOUNT_TCP) {
298	sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
299	} else {
300	sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
301	}
302
303	if (sock == -1) {
304	perror("socket");
305	goto bail;
306	}
307
308	if (bindresvport(sock, 0) == -1) {
309	perror("bindresvport");
310	goto bail;
311	}
312
313	addr.sin_family = AF_INET;
314	addr.sin_addr.s_addr = server;
315	addr.sin_port = htons(nfs_port);
316	memcpy(&data->addr, &addr, sizeof(data->addr));
317
318	strncpy(data->hostname, hostname, sizeof(data->hostname));
319
320	data->fd = sock;
321
322	mountflags = (data->flags & NFS_MOUNT_KLIBC_RONLY) ? MS_RDONLY : 0;
323	data->flags = data->flags & NFS_MOUNT_FLAGMASK;
324	ret = mount(pathname, path, "nfs", mountflags, data);
325
326	if (ret == -1) {
327	if (errno == ENODEV) {
328	fprintf(stderr, "mount: the kernel lacks NFS v%d "
329	"support\n",
330	(data->flags & NFS_MOUNT_VER3) ? 3 : 2);
331	} else {
332	perror("mount");
333	}
334	goto bail;
335	}
336
337	DEBUG(("Mounted %s on %s\n", pathname, path));
338
339	goto done;
340
341	bail:
342	if (mounted) {
343	if (data->flags & NFS_MOUNT_VER3) {
344	umount_v3(path, clnt);
345	} else {
346	umount_v2(path, clnt);
347	}
348	}
349
350	ret = -1;
351
352	done:
353	if (clnt) {
354	client_free(clnt);
355	}
356
357	if (sock != -1) {
358	close(sock);
359	}
360
361	return ret;
362	}