rpc.c revision 199767f8919635c4928607450d9e0abb932109ce
/* $NetBSD: rpc.c,v 1.18 1998/01/23 19:27:45 thorpej Exp $ */
/*
* Copyright (c) 1992 Regents of the University of California.
* All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL)
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* RPC functions used by NFS and bootparams.
* Note that bootparams requires the ability to find out the
* address of the server from which its response has come.
* This is supported by keeping the IP/UDP headers in the
* buffer space provided by the caller. (See rpc_fromaddr)
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <string.h>
#include "rpcv2.h"
#include "stand.h"
#include "net.h"
#include "netif.h"
#include "rpc.h"
struct auth_info {
int32_t authtype; /* auth type */
u_int32_t authlen; /* auth length */
};
struct auth_unix {
int32_t ua_time;
int32_t ua_hostname; /* null */
int32_t ua_uid;
int32_t ua_gid;
int32_t ua_gidlist; /* null */
};
struct rpc_call {
u_int32_t rp_xid; /* request transaction id */
int32_t rp_direction; /* call direction (0) */
u_int32_t rp_rpcvers; /* rpc version (2) */
u_int32_t rp_prog; /* program */
u_int32_t rp_vers; /* version */
u_int32_t rp_proc; /* procedure */
};
struct rpc_reply {
u_int32_t rp_xid; /* request transaction id */
int32_t rp_direction; /* call direction (1) */
int32_t rp_astatus; /* accept status (0: accepted) */
union {
u_int32_t rpu_errno;
struct {
struct auth_info rok_auth;
u_int32_t rok_status;
} rpu_rok;
} rp_u;
};
/* Local forwards */
static ssize_t recvrpc(struct iodesc *, void *, size_t, time_t);
static int rpc_getport(struct iodesc *, n_long, n_long);
int rpc_xid;
int rpc_port = 0x400; /* predecrement */
/*
* Make a rpc call; return length of answer
* Note: Caller must leave room for headers.
*/
ssize_t
rpc_call(struct iodesc *d, n_long prog, n_long vers, n_long proc,
void *sdata, size_t slen, void *rdata, size_t rlen)
{
ssize_t cc;
struct auth_info *auth;
struct rpc_call *call;
struct rpc_reply *reply;
char *send_head, *send_tail;
char *recv_head, *recv_tail;
n_long x;
int port; /* host order */
#ifdef RPC_DEBUG
if (debug)
printf("rpc_call: prog=0x%x vers=%d proc=%d\n",
prog, vers, proc);
#endif
port = rpc_getport(d, prog, vers);
if (port == -1)
return (-1);
d->destport = htons(port);
/*
* Prepend authorization stuff and headers.
* Note, must prepend things in reverse order.
*/
send_head = sdata;
send_tail = (char *)sdata + slen;
/* Auth verifier is always auth_null */
send_head -= sizeof(*auth);
auth = (struct auth_info *)send_head;
auth->authtype = htonl(RPCAUTH_NULL);
auth->authlen = 0;
#if 1
/* Auth credentials: always auth unix (as root) */
send_head -= sizeof(struct auth_unix);
bzero(send_head, sizeof(struct auth_unix));
send_head -= sizeof(*auth);
auth = (struct auth_info *)send_head;
auth->authtype = htonl(RPCAUTH_UNIX);
auth->authlen = htonl(sizeof(struct auth_unix));
#else
/* Auth credentials: always auth_null (XXX OK?) */
send_head -= sizeof(*auth);
auth = send_head;
auth->authtype = htonl(RPCAUTH_NULL);
auth->authlen = 0;
#endif
/* RPC call structure. */
send_head -= sizeof(*call);
call = (struct rpc_call *)send_head;
rpc_xid++;
call->rp_xid = htonl(rpc_xid);
call->rp_direction = htonl(RPC_CALL);
call->rp_rpcvers = htonl(RPC_VER2);
call->rp_prog = htonl(prog);
call->rp_vers = htonl(vers);
call->rp_proc = htonl(proc);
/* Make room for the rpc_reply header. */
recv_head = rdata;
recv_tail = (char *)rdata + rlen;
recv_head -= sizeof(*reply);
cc = sendrecv(d,
sendudp, send_head, send_tail - send_head,
recvrpc, recv_head, recv_tail - recv_head);
#ifdef RPC_DEBUG
if (debug)
printf("callrpc: cc=%ld rlen=%lu\n", (long)cc, (u_long)rlen);
#endif
if (cc == -1)
return (-1);
if (cc <= sizeof(*reply)) {
errno = EBADRPC;
return (-1);
}
recv_tail = recv_head + cc;
/*
* Check the RPC reply status.
* The xid, dir, astatus were already checked.
*/
reply = (struct rpc_reply *)recv_head;
auth = &reply->rp_u.rpu_rok.rok_auth;
x = ntohl(auth->authlen);
if (x != 0) {
#ifdef RPC_DEBUG
if (debug)
printf("callrpc: reply auth != NULL\n");
#endif
errno = EBADRPC;
return(-1);
}
x = ntohl(reply->rp_u.rpu_rok.rok_status);
if (x != 0) {
printf("callrpc: error = %ld\n", (long)x);
errno = EBADRPC;
return(-1);
}
recv_head += sizeof(*reply);
return (ssize_t)(recv_tail - recv_head);
}
/*
* Returns true if packet is the one we're waiting for.
* This just checks the XID, direction, acceptance.
* Remaining checks are done by callrpc
*/
static ssize_t
recvrpc(struct iodesc *d, void *pkt, size_t len, time_t tleft)
{
struct rpc_reply *reply;
ssize_t n;
int x;
errno = 0;
#ifdef RPC_DEBUG
if (debug)
printf("recvrpc: called len=%lu\n", (u_long)len);
#endif
n = readudp(d, pkt, len, tleft);
if (n <= (4 * 4))
return -1;
reply = (struct rpc_reply *)pkt;
x = ntohl(reply->rp_xid);
if (x != rpc_xid) {
#ifdef RPC_DEBUG
if (debug)
printf("recvrpc: rp_xid %d != xid %d\n", x, rpc_xid);
#endif
return -1;
}
x = ntohl(reply->rp_direction);
if (x != RPC_REPLY) {
#ifdef RPC_DEBUG
if (debug)
printf("recvrpc: rp_direction %d != REPLY\n", x);
#endif
return -1;
}
x = ntohl(reply->rp_astatus);
if (x != RPC_MSGACCEPTED) {
errno = ntohl(reply->rp_u.rpu_errno);
printf("recvrpc: reject, astat=%d, errno=%d\n", x, errno);
return -1;
}
/* Return data count (thus indicating success) */
return (n);
}
/*
* Given a pointer to a reply just received,
* dig out the IP address/port from the headers.
*/
void
rpc_fromaddr(void *pkt, struct in_addr *addr, u_short *port)
{
struct hackhdr {
/* Tail of IP header: just IP addresses */
n_long ip_src;
n_long ip_dst;
/* UDP header: */
u_int16_t uh_sport; /* source port */
u_int16_t uh_dport; /* destination port */
int16_t uh_ulen; /* udp length */
u_int16_t uh_sum; /* udp checksum */
/* RPC reply header: */
struct rpc_reply rpc;
} *hhdr;
hhdr = ((struct hackhdr *)pkt) - 1;
addr->s_addr = hhdr->ip_src;
*port = hhdr->uh_sport;
}
/*
* RPC Portmapper cache
*/
#define PMAP_NUM 8 /* need at most 5 pmap entries */
int rpc_pmap_num;
struct pmap_list {
struct in_addr addr; /* server, net order */
u_int prog; /* host order */
u_int vers; /* host order */
int port; /* host order */
} rpc_pmap_list[PMAP_NUM];
/*
* return port number in host order, or -1.
* arguments are:
* addr .. server, net order.
* prog .. host order.
* vers .. host order.
*/
int
rpc_pmap_getcache(struct in_addr addr, u_int prog, u_int vers)
{
struct pmap_list *pl;
for (pl = rpc_pmap_list; pl < &rpc_pmap_list[rpc_pmap_num]; pl++) {
if (pl->addr.s_addr == addr.s_addr &&
pl->prog == prog && pl->vers == vers )
{
return (pl->port);
}
}
return (-1);
}
/*
* arguments are:
* addr .. server, net order.
* prog .. host order.
* vers .. host order.
* port .. host order.
*/
void
rpc_pmap_putcache(struct in_addr addr, u_int prog, u_int vers, int port)
{
struct pmap_list *pl;
/* Don't overflow cache... */
if (rpc_pmap_num >= PMAP_NUM) {
/* ... just re-use the last entry. */
rpc_pmap_num = PMAP_NUM - 1;
#ifdef RPC_DEBUG
printf("rpc_pmap_putcache: cache overflow\n");
#endif
}
pl = &rpc_pmap_list[rpc_pmap_num];
rpc_pmap_num++;
/* Cache answer */
pl->addr = addr;
pl->prog = prog;
pl->vers = vers;
pl->port = port;
}
/*
* Request a port number from the port mapper.
* Returns the port in host order.
* prog and vers are host order.
*/
int
rpc_getport(struct iodesc *d, n_long prog, n_long vers)
{
struct args {
n_long prog; /* call program */
n_long vers; /* call version */
n_long proto; /* call protocol */
n_long port; /* call port (unused) */
} *args;
struct res {
n_long port;
} *res;
struct {
n_long h[RPC_HEADER_WORDS];
struct args d;
} sdata;
struct {
n_long h[RPC_HEADER_WORDS];
struct res d;
n_long pad;
} rdata;
ssize_t cc;
int port;
#ifdef RPC_DEBUG
if (debug)
printf("%s: prog=0x%x vers=%d\n", __func__, prog, vers);
#endif
/* This one is fixed forever. */
if (prog == PMAPPROG) {
port = PMAPPORT;
goto out;
}
/* Try for cached answer first */
port = rpc_pmap_getcache(d->destip, prog, vers);
if (port != -1)
goto out;
args = &sdata.d;
args->prog = htonl(prog);
args->vers = htonl(vers);
args->proto = htonl(IPPROTO_UDP);
args->port = 0;
res = &rdata.d;
cc = rpc_call(d, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT,
args, sizeof(*args), res, sizeof(*res));
if (cc < sizeof(*res)) {
printf("getport: %s", strerror(errno));
errno = EBADRPC;
return (-1);
}
port = (int)ntohl(res->port);
rpc_pmap_putcache(d->destip, prog, vers, port);
out:
#ifdef RPC_DEBUG
if (debug)
printf("%s: port=%u\n", __func__, port);
#endif
return (port);
}