summaryrefslogtreecommitdiffstats
path: root/support/nfs/conn.c
blob: a020394c86b7dc1541b58b3dcd823eaeefe8d6ff (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/*
 * conn.c -- NFS client mount / umount connection code support functions
 *
 * 2006-06-06 Amit Gud <agud@redhat.com>
 * - Moved code snippets to nfs-utils/support/nfs from util-linux/mount/nfsmount.c
 *
 */

#include <errno.h>
#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "conn.h"

extern int verbose;

/* Map an NFS version into the corresponding Mountd version */
u_long nfsvers_to_mnt(const u_long vers)
{
	static const u_long nfs_to_mnt[] = { 0, 0, 1, 3 };
	if (vers <= 3)
		return nfs_to_mnt[vers];
	return 0;
}

/* Map a Mountd version into the corresponding NFS version */
u_long mntvers_to_nfs(const u_long vers)
{
	static const u_long mnt_to_nfs[] = { 0, 2, 2, 3 };
	if (vers <= 3)
		return mnt_to_nfs[vers];
	return 0;
}

/*
 * Create a socket that is locally bound to a 
 * reserve or non-reserve port. For any failures,
 * RPC_ANYSOCK is returned which will cause 
 * the RPC code to create the socket instead. 
 */
int get_socket(struct sockaddr_in *saddr, u_int p_prot, int resvp)
{
	int so, cc, type;
	struct sockaddr_in laddr;
	socklen_t namelen = sizeof(laddr);

	type = (p_prot == IPPROTO_UDP ? SOCK_DGRAM : SOCK_STREAM);
	if ((so = socket (AF_INET, type, p_prot)) < 0) {
		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
		rpc_createerr.cf_error.re_errno = errno;
		if (verbose) {
			fprintf(stderr, 
				"mount: Unable to create %s socket: errno %d (%s)\n",
				p_prot == IPPROTO_UDP ? "UDP" : "TCP", 
				errno, strerror(errno));
		}
		return RPC_ANYSOCK;
	}
	laddr.sin_family = AF_INET;
	laddr.sin_port = 0;
	laddr.sin_addr.s_addr = htonl(INADDR_ANY);
	if (resvp) {
		if (bindresvport(so, &laddr) < 0) {
			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
			rpc_createerr.cf_error.re_errno = errno;
			if (verbose) {
				fprintf(stderr, 
					"mount: Unable to bindresvport %s socket: errno %d (%s)\n",
					p_prot == IPPROTO_UDP ? "UDP" : "TCP", 
					errno, strerror(errno));
			}
			close(so);
			return RPC_ANYSOCK;
		}
	} else {
		cc = bind(so, (struct sockaddr *)&laddr, namelen);
		if (cc < 0) {
			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
			rpc_createerr.cf_error.re_errno = errno;
			if (verbose) {
				fprintf(stderr, 
					"mount: Unable to bind to %s socket: errno %d (%s)\n",
					p_prot == IPPROTO_UDP ? "UDP" : "TCP", 
					errno, strerror(errno));
			}
			close(so);
			return RPC_ANYSOCK;
		}
	}
	if (type == SOCK_STREAM) {
		cc = connect(so, (struct sockaddr *)saddr, namelen);
		if (cc < 0) {
			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
			rpc_createerr.cf_error.re_errno = errno;
			if (verbose) {
				fprintf(stderr, 
					"mount: Unable to connect to %s:%d, errno %d (%s)\n",
					inet_ntoa(saddr->sin_addr), ntohs(saddr->sin_port),
					errno, strerror(errno));
			}
			close(so);
			return RPC_ANYSOCK;
		}
	}
	return so;
}

/*
 * Sigh... getport() doesn't actually check the version number.
 * In order to make sure that the server actually supports the service
 * we're requesting, we open and RPC client, and fire off a NULL
 * RPC call.
 */
int
clnt_ping(struct sockaddr_in *saddr, const u_long prog, const u_long vers,
	  const u_int prot)
{
	CLIENT *clnt=NULL;
	int sock, stat;
	static char clnt_res;

	rpc_createerr.cf_stat = stat = errno = 0;
	sock = get_socket(saddr, prot, FALSE);
	if (sock == RPC_ANYSOCK && errno == ETIMEDOUT) {
		/*
		 * TCP timeout. Bubble up the error to see 
		 * how it should be handled.
		 */
		rpc_createerr.cf_stat = RPC_TIMEDOUT;
		goto out_bad;
	}

	switch(prot) {
	case IPPROTO_UDP:
		clnt = clntudp_bufcreate(saddr, prog, vers,
					 RETRY_TIMEOUT, &sock,
					 RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
		break;
	case IPPROTO_TCP:
		clnt = clnttcp_create(saddr, prog, vers, &sock,
				      RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
		break;
	default:
		goto out_bad;
	}
	if (!clnt)
		goto out_bad;
	memset(&clnt_res, 0, sizeof(clnt_res));
	stat = clnt_call(clnt, NULLPROC,
			 (xdrproc_t)xdr_void, (caddr_t)NULL,
			 (xdrproc_t)xdr_void, (caddr_t)&clnt_res,
			 TIMEOUT);
	if (stat) {
		clnt_geterr(clnt, &rpc_createerr.cf_error);
		rpc_createerr.cf_stat = stat;
	}
	clnt_destroy(clnt);
	if (sock != -1)
		close(sock);

	if (stat == RPC_SUCCESS)
		return 1;

 out_bad:
	return 0;
}

CLIENT *mnt_openclnt(clnt_addr_t *mnt_server, int *msock)
{
	struct sockaddr_in *mnt_saddr = &mnt_server->saddr;
	struct pmap *mnt_pmap = &mnt_server->pmap;
	CLIENT *clnt = NULL;

	/* contact the mount daemon via TCP */
	mnt_saddr->sin_port = htons((u_short)mnt_pmap->pm_port);
	*msock = get_socket(mnt_saddr, mnt_pmap->pm_prot, TRUE);

	switch (mnt_pmap->pm_prot) {
	case IPPROTO_UDP:
		clnt = clntudp_bufcreate(mnt_saddr,
					 mnt_pmap->pm_prog, mnt_pmap->pm_vers,
					 RETRY_TIMEOUT, msock,
					 MNT_SENDBUFSIZE, MNT_RECVBUFSIZE);
		break;
	case IPPROTO_TCP:
		clnt = clnttcp_create(mnt_saddr,
				      mnt_pmap->pm_prog, mnt_pmap->pm_vers,
				      msock,
				      MNT_SENDBUFSIZE, MNT_RECVBUFSIZE);
		break;
	}
	if (clnt) {
		/* try to mount hostname:dirname */
		clnt->cl_auth = authunix_create_default();
		return clnt;
	}
	return NULL;
}

void mnt_closeclnt(CLIENT *clnt, int msock)
{
	auth_destroy(clnt->cl_auth);
	clnt_destroy(clnt);
	close(msock);
}