xref: /netbsd-src/sys/lib/libsa/rpc.c (revision ae1bfcddc410612bc8c58b807e1830becb69a24c)
1 /*
2  * Copyright (c) 1992 Regents of the University of California.
3  * All rights reserved.
4  *
5  * This software was developed by the Computer Systems Engineering group
6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7  * contributed to Berkeley.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Lawrence Berkeley Laboratory and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  * from @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp  (LBL)
38  *   $Id: rpc.c,v 1.1 1994/05/08 16:11:35 brezak Exp $
39  */
40 
41 #include <sys/param.h>
42 #include <sys/socket.h>
43 
44 #include <netinet/in.h>
45 #include <netinet/in_systm.h>
46 
47 #include <nfs/rpcv2.h>
48 #include <nfs/nfsv2.h>
49 #undef NFSX_FATTR
50 #include <string.h>
51 
52 #include "stand.h"
53 #include "net.h"
54 #include "netif.h"
55 #include "rpc.h"
56 
57 /* XXX Data part of nfs rpc reply (also the largest thing we receive) */
58 struct nfs_reply_data {
59 	u_long	errno;
60 #ifndef NFSX_FATTR
61 	struct	nfsv2_fattr fa;
62 #else
63 	u_char	fa[NFSX_FATTR(0)];
64 #endif
65 	u_long	count;
66 	u_char	data[1200];
67 };
68 #define NFSREAD_SIZE sizeof(((struct nfs_reply_data *)0)->data)
69 
70 /* Cache stuff */
71 #define PMAP_NUM 8			/* need at most 5 pmap entries */
72 
73 static struct pmap_list {
74 	u_long	addr;			/* address of server */
75 	u_long	prog;
76 	u_long	vers;
77 	u_short	port;			/* cached port for service */
78 } pmap_list[PMAP_NUM] = {
79 	{ 0, PMAPPROG, PMAPVERS, PMAPPORT }
80 };
81 static	int pmap_num = 1;
82 
83 /* Local forwards */
84 static	int recvrpc __P((struct iodesc *, void *, int));
85 
86 /* Make a rpc call; return length of answer */
87 int
88 callrpc(d, prog, vers, proc, sdata, slen, rdata, rlen)
89 	register struct iodesc *d;
90 	register u_long prog, vers, proc;
91 	register void *sdata;
92 	register int slen;
93 	register void *rdata;
94 	register int rlen;
95 {
96 	register int cc;
97 	register struct rpc_call *rpc;
98 	struct {
99 		u_char	header[HEADER_SIZE];
100 		struct	rpc_call wrpc;
101 		u_char	data[sizeof(struct nfs_reply_data)]; /* XXX */
102 	} wbuf;
103 	struct {
104 		u_char header[HEADER_SIZE];
105 		struct	rpc_reply rrpc;
106 		union {
107 			u_long	errno;
108 			u_char	data[sizeof(struct nfs_reply_data)];
109 		} ru;
110 	} rbuf;
111 
112 #ifdef RPC_DEBUG
113 	if (debug)
114 	    printf("callrpc: called\n");
115 #endif
116 	if (rlen > sizeof(rbuf.ru.data))
117 		panic("callrpc: huge read (%d > %d)",
118 		    rlen, sizeof(rbuf.ru.data));
119 
120 	d->destport = getport(d, prog, vers);
121 
122 	rpc = &wbuf.wrpc;
123 
124 	bzero(rpc, sizeof(*rpc));
125 
126 	rpc->rp_xid = d->xid;
127 	rpc->rp_rpcvers = htonl(RPC_MSG_VERSION);
128 	rpc->rp_prog = htonl(prog);
129 	rpc->rp_vers = htonl(vers);
130 	rpc->rp_proc = htonl(proc);
131 	bcopy(sdata, wbuf.data, slen);
132 
133 	cc = sendrecv(d, sendudp, rpc, sizeof(*rpc) + slen, recvrpc,
134 	    ((u_char *)&rbuf.rrpc) - HEADER_SIZE, sizeof(rbuf) - HEADER_SIZE);
135 
136 	if (cc < rlen) {
137 		/* Check for an error return */
138 		if (cc >= sizeof(rbuf.ru.errno) && rbuf.ru.errno != 0) {
139 			errno = ntohl(rbuf.ru.errno);
140 			return (-1);
141 		}
142 		panic("callrpc: missing data (%d < %d)", cc, rlen);
143 	}
144 	if (cc > sizeof(rbuf.ru.data))
145 		panic("callrpc: huge return (%d > %d)",
146 		    cc, sizeof(rbuf.ru.data));
147 	bcopy(rbuf.ru.data, rdata, cc);
148 	return (cc);
149 }
150 
151 /* Returns true if packet is the one we're waiting for */
152 static int
153 recvrpc(d, pkt, len)
154 	register struct iodesc *d;
155 	register void *pkt;
156 	int len;
157 {
158 	register struct rpc_reply *rpc;
159 
160 	errno = 0;
161 #ifdef RPC_DEBUG
162 	if (debug)
163 	    printf("recvrpc: called\n");
164 #endif
165 	rpc = (struct rpc_reply *)checkudp(d, pkt, &len);
166 	if (rpc == NULL || len < sizeof(*rpc)) {
167 #ifdef RPC_DEBUG
168 		if (debug)
169 			printf("recvrpc: bad response rpc=%x len=%d\n",
170 				(u_int)rpc, len);
171 #endif
172 		return (-1);
173 	}
174 
175 	NTOHL(rpc->rp_direction);
176 	NTOHL(rpc->rp_stat);
177 
178 	if (rpc->rp_xid != d->xid || rpc->rp_direction != REPLY ||
179 	    rpc->rp_stat != MSG_ACCEPTED) {
180 #ifdef RPC_DEBUG
181 		if (debug) {
182 			if (rpc->rp_xid != d->xid)
183 				printf("recvrpc: rp_xid %d != xid %d\n",
184 					rpc->rp_xid, d->xid);
185 			if (rpc->rp_direction != REPLY)
186 				printf("recvrpc: %d != REPLY\n", rpc->rp_direction);
187 			if (rpc->rp_stat != MSG_ACCEPTED)
188 				printf("recvrpc: %d != MSG_ACCEPTED\n", rpc->rp_stat);
189 		}
190 #endif
191 		return (-1);
192 	}
193 
194 	/* Bump xid so next request will be unique */
195 	++d->xid;
196 
197 	/* Return data count (thus indicating success) */
198 	return (len - sizeof(*rpc));
199 }
200 
201 /* Request a port number from the port mapper */
202 u_short
203 getport(d, prog, vers)
204 	register struct iodesc *d;
205 	u_long prog;
206 	u_long vers;
207 {
208 	register int i;
209 	register struct pmap_list *pl;
210 	u_long port;
211 	struct {
212 		u_long	prog;		/* call program */
213 		u_long	vers;		/* call version */
214 		u_long	proto;		/* call protocol */
215 		u_long	port;		/* call port (unused) */
216 	} sdata;
217 
218 #ifdef RPC_DEBUG
219 	if (debug)
220 	    printf("getport: called\n");
221 #endif
222 	/* Try for cached answer first */
223 	for (i = 0, pl = pmap_list; i < pmap_num; ++i, ++pl)
224 		if ((pl->addr == d->destip || pl->addr == 0) &&
225 		    pl->prog == prog && pl->vers == vers)
226 			return (pl->port);
227 
228 	/* Don't overflow cache */
229 	if (pmap_num > PMAP_NUM - 1)
230 		panic("getport: overflowed pmap_list!");
231 
232 	sdata.prog = htonl(prog);
233 	sdata.vers = htonl(vers);
234 	sdata.proto = htonl(IPPROTO_UDP);
235 	sdata.port = 0;
236 
237 	if (callrpc(d, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT,
238 		&sdata, sizeof(sdata), &port, sizeof(port)) < 0) {
239 		printf("getport: %s", strerror(errno));
240 		return(-1);
241 	}
242 
243 	/* Cache answer */
244 	pl->addr = d->destip;
245 	pl->prog = prog;
246 	pl->vers = vers;
247 	pl->port = port;
248 	++pmap_num;
249 
250 	return ((u_short)port);
251 }
252