OpenBSD-4.6/lib/libc/rpc/clnt_tcp.c
/* $OpenBSD: clnt_tcp.c,v 1.24 2009/06/02 14:18:19 schwarze Exp $ */
/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
/*
* clnt_tcp.c, Implements a TCP/IP based, client side RPC.
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*
* TCP based RPC supports 'batched calls'.
* A sequence of calls may be batched-up in a send buffer. The rpc call
* return immediately to the client even though the call was not necessarily
* sent. The batching occurs if the results' xdr routine is NULL (0) AND
* the rpc timeout value is zero (see clnt.h, rpc).
*
* Clients should NOT casually batch calls that in fact return results; that is,
* the server side should be aware that a call is batched and not produce any
* return message. Batched calls that produce many result messages can
* deadlock (netlock) the client and the server....
*
* Now go hang yourself.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <netdb.h>
#include <errno.h>
#include <rpc/pmap_clnt.h>
#define MCALL_MSG_SIZE 24
static enum clnt_stat clnttcp_call(CLIENT *, u_long, xdrproc_t, caddr_t,
xdrproc_t, caddr_t, struct timeval);
static void clnttcp_abort(CLIENT *);
static void clnttcp_geterr(CLIENT *, struct rpc_err *);
static bool_t clnttcp_freeres(CLIENT *, xdrproc_t, caddr_t);
static bool_t clnttcp_control(CLIENT *, u_int, void *);
static void clnttcp_destroy(CLIENT *);
static struct clnt_ops tcp_ops = {
clnttcp_call,
clnttcp_abort,
clnttcp_geterr,
clnttcp_freeres,
clnttcp_destroy,
clnttcp_control
};
struct ct_data {
int ct_sock;
bool_t ct_closeit;
struct timeval ct_wait;
bool_t ct_waitset; /* wait set by clnt_control? */
struct sockaddr_in ct_addr;
struct rpc_err ct_error;
char ct_mcall[MCALL_MSG_SIZE]; /* marshalled callmsg */
u_int ct_mpos; /* pos after marshal */
XDR ct_xdrs;
};
static int readtcp(struct ct_data *, caddr_t, int);
static int writetcp(struct ct_data *, caddr_t, int);
/*
* Create a client handle for a tcp/ip connection.
* If *sockp<0, *sockp is set to a newly created TCP socket and it is
* connected to raddr. If *sockp non-negative then
* raddr is ignored. The rpc/tcp package does buffering
* similar to stdio, so the client must pick send and receive buffer sizes,];
* 0 => use the default.
* If raddr->sin_port is 0, then a binder on the remote machine is
* consulted for the right port number.
* NB: *sockp is copied into a private area.
* NB: It is the clients responsibility to close *sockp.
* NB: The rpch->cl_auth is set null authentication. Caller may wish to set this
* something more useful.
*/
CLIENT *
clnttcp_create(struct sockaddr_in *raddr, u_long prog, u_long vers, int *sockp,
u_int sendsz, u_int recvsz)
{
CLIENT *h;
struct ct_data *ct = NULL;
struct timeval now;
struct rpc_msg call_msg;
h = (CLIENT *)mem_alloc(sizeof(*h));
if (h == NULL) {
(void)fprintf(stderr, "clnttcp_create: out of memory\n");
rpc_createerr.cf_stat = RPC_SYSTEMERROR;
rpc_createerr.cf_error.re_errno = errno;
goto fooy;
}
ct = (struct ct_data *)mem_alloc(sizeof(*ct));
if (ct == NULL) {
(void)fprintf(stderr, "clnttcp_create: out of memory\n");
rpc_createerr.cf_stat = RPC_SYSTEMERROR;
rpc_createerr.cf_error.re_errno = errno;
goto fooy;
}
/*
* If no port number given ask the pmap for one
*/
if (raddr->sin_port == 0) {
u_short port;
if ((port = pmap_getport(raddr, prog, vers, IPPROTO_TCP)) == 0) {
mem_free((caddr_t)ct, sizeof(struct ct_data));
mem_free((caddr_t)h, sizeof(CLIENT));
return (NULL);
}
raddr->sin_port = htons(port);
}
/*
* If no socket given, open one
*/
if (*sockp < 0) {
*sockp = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
(void)bindresvport(*sockp, NULL);
if ((*sockp < 0)
|| (connect(*sockp, (struct sockaddr *)raddr,
sizeof(*raddr)) < 0)) {
rpc_createerr.cf_stat = RPC_SYSTEMERROR;
rpc_createerr.cf_error.re_errno = errno;
if (*sockp != -1)
(void)close(*sockp);
goto fooy;
}
ct->ct_closeit = TRUE;
} else {
ct->ct_closeit = FALSE;
}
/*
* Set up private data struct
*/
ct->ct_sock = *sockp;
ct->ct_wait.tv_usec = 0;
ct->ct_waitset = FALSE;
ct->ct_addr = *raddr;
/*
* Initialize call message
*/
(void)gettimeofday(&now, NULL);
call_msg.rm_xid = arc4random();
call_msg.rm_direction = CALL;
call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
call_msg.rm_call.cb_prog = prog;
call_msg.rm_call.cb_vers = vers;
/*
* pre-serialize the static part of the call msg and stash it away
*/
xdrmem_create(&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE,
XDR_ENCODE);
if (! xdr_callhdr(&(ct->ct_xdrs), &call_msg)) {
if (ct->ct_closeit) {
(void)close(*sockp);
}
goto fooy;
}
ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
XDR_DESTROY(&(ct->ct_xdrs));
/*
* Create a client handle which uses xdrrec for serialization
* and authnone for authentication.
*/
xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
(caddr_t)ct, (int(*)(caddr_t, caddr_t, int))readtcp,
(int(*)(caddr_t, caddr_t, int))writetcp);
h->cl_ops = &tcp_ops;
h->cl_private = (caddr_t) ct;
h->cl_auth = authnone_create();
if (h->cl_auth == NULL) {
rpc_createerr.cf_stat = RPC_SYSTEMERROR;
rpc_createerr.cf_error.re_errno = errno;
goto fooy;
}
return (h);
fooy:
/*
* Something goofed, free stuff and barf
*/
if (ct)
mem_free((caddr_t)ct, sizeof(struct ct_data));
if (h)
mem_free((caddr_t)h, sizeof(CLIENT));
return (NULL);
}
static enum clnt_stat
clnttcp_call(CLIENT *h, u_long proc, xdrproc_t xdr_args, caddr_t args_ptr,
xdrproc_t xdr_results, caddr_t results_ptr, struct timeval timeout)
{
struct ct_data *ct = (struct ct_data *) h->cl_private;
XDR *xdrs = &(ct->ct_xdrs);
struct rpc_msg reply_msg;
u_long x_id;
u_int32_t *msg_x_id = (u_int32_t *)(ct->ct_mcall); /* yuk */
bool_t shipnow;
int refreshes = 2;
if (!ct->ct_waitset) {
ct->ct_wait = timeout;
}
shipnow =
(xdr_results == NULL && timeout.tv_sec == 0
&& timeout.tv_usec == 0) ? FALSE : TRUE;
call_again:
xdrs->x_op = XDR_ENCODE;
ct->ct_error.re_status = RPC_SUCCESS;
x_id = ntohl(--(*msg_x_id));
if ((! XDR_PUTBYTES(xdrs, ct->ct_mcall, ct->ct_mpos)) ||
(! XDR_PUTLONG(xdrs, (long *)&proc)) ||
(! AUTH_MARSHALL(h->cl_auth, xdrs)) ||
(! (*xdr_args)(xdrs, args_ptr))) {
if (ct->ct_error.re_status == RPC_SUCCESS)
ct->ct_error.re_status = RPC_CANTENCODEARGS;
(void)xdrrec_endofrecord(xdrs, TRUE);
return (ct->ct_error.re_status);
}
if (! xdrrec_endofrecord(xdrs, shipnow))
return (ct->ct_error.re_status = RPC_CANTSEND);
if (! shipnow)
return (RPC_SUCCESS);
/*
* Hack to provide rpc-based message passing
*/
if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
return(ct->ct_error.re_status = RPC_TIMEDOUT);
}
/*
* Keep receiving until we get a valid transaction id
*/
xdrs->x_op = XDR_DECODE;
while (TRUE) {
reply_msg.acpted_rply.ar_verf = _null_auth;
reply_msg.acpted_rply.ar_results.where = NULL;
reply_msg.acpted_rply.ar_results.proc = xdr_void;
if (! xdrrec_skiprecord(xdrs))
return (ct->ct_error.re_status);
/* now decode and validate the response header */
if (! xdr_replymsg(xdrs, &reply_msg)) {
if (ct->ct_error.re_status == RPC_SUCCESS)
continue;
return (ct->ct_error.re_status);
}
if (reply_msg.rm_xid == x_id)
break;
}
/*
* process header
*/
_seterr_reply(&reply_msg, &(ct->ct_error));
if (ct->ct_error.re_status == RPC_SUCCESS) {
if (! AUTH_VALIDATE(h->cl_auth, &reply_msg.acpted_rply.ar_verf)) {
ct->ct_error.re_status = RPC_AUTHERROR;
ct->ct_error.re_why = AUTH_INVALIDRESP;
} else if (! (*xdr_results)(xdrs, results_ptr)) {
if (ct->ct_error.re_status == RPC_SUCCESS)
ct->ct_error.re_status = RPC_CANTDECODERES;
}
/* free verifier ... */
if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
xdrs->x_op = XDR_FREE;
(void)xdr_opaque_auth(xdrs, &(reply_msg.acpted_rply.ar_verf));
}
} /* end successful completion */
else {
/* maybe our credentials need to be refreshed ... */
if (refreshes-- && AUTH_REFRESH(h->cl_auth))
goto call_again;
} /* end of unsuccessful completion */
return (ct->ct_error.re_status);
}
static void
clnttcp_geterr(CLIENT *h, struct rpc_err *errp)
{
struct ct_data *ct =
(struct ct_data *) h->cl_private;
*errp = ct->ct_error;
}
static bool_t
clnttcp_freeres(CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
{
struct ct_data *ct = (struct ct_data *)cl->cl_private;
XDR *xdrs = &(ct->ct_xdrs);
xdrs->x_op = XDR_FREE;
return ((*xdr_res)(xdrs, res_ptr));
}
/*ARGSUSED*/
static void
clnttcp_abort(CLIENT *clnt)
{
}
static bool_t
clnttcp_control(CLIENT *cl, u_int request, void *info)
{
struct ct_data *ct = (struct ct_data *)cl->cl_private;
switch (request) {
case CLSET_TIMEOUT:
ct->ct_wait = *(struct timeval *)info;
ct->ct_waitset = TRUE;
break;
case CLGET_TIMEOUT:
*(struct timeval *)info = ct->ct_wait;
break;
case CLGET_SERVER_ADDR:
*(struct sockaddr_in *)info = ct->ct_addr;
break;
default:
return (FALSE);
}
return (TRUE);
}
static void
clnttcp_destroy(CLIENT *h)
{
struct ct_data *ct =
(struct ct_data *) h->cl_private;
if (ct->ct_closeit) {
(void)close(ct->ct_sock);
}
XDR_DESTROY(&(ct->ct_xdrs));
mem_free((caddr_t)ct, sizeof(struct ct_data));
mem_free((caddr_t)h, sizeof(CLIENT));
}
/*
* Interface between xdr serializer and tcp connection.
* Behaves like the system calls, read & write, but keeps some error state
* around for the rpc level.
*/
static int
readtcp(struct ct_data *ct, caddr_t buf, int len)
{
struct pollfd pfd[1];
struct timeval start, after, duration, tmp;
int delta, r, save_errno;
if (len == 0)
return (0);
pfd[0].fd = ct->ct_sock;
pfd[0].events = POLLIN;
delta = ct->ct_wait.tv_sec * 1000 + ct->ct_wait.tv_usec / 1000;
gettimeofday(&start, NULL);
for (;;) {
r = poll(pfd, 1, delta);
save_errno = errno;
gettimeofday(&after, NULL);
timersub(&start, &after, &duration);
timersub(&ct->ct_wait, &duration, &tmp);
delta = tmp.tv_sec * 1000 + tmp.tv_usec / 1000;
if (delta <= 0)
r = 0;
switch (r) {
case 0:
ct->ct_error.re_status = RPC_TIMEDOUT;
return (-1);
case 1:
if (pfd[0].revents & POLLNVAL)
errno = EBADF;
else if (pfd[0].revents & POLLERR)
errno = EIO;
else
break;
/* FALLTHROUGH */
case -1:
if (errno == EINTR)
continue;
ct->ct_error.re_status = RPC_CANTRECV;
ct->ct_error.re_errno = save_errno;
return (-1);
}
break;
}
switch (len = read(ct->ct_sock, buf, len)) {
case 0:
/* premature eof */
ct->ct_error.re_errno = ECONNRESET;
ct->ct_error.re_status = RPC_CANTRECV;
len = -1; /* it's really an error */
break;
case -1:
ct->ct_error.re_errno = errno;
ct->ct_error.re_status = RPC_CANTRECV;
break;
}
return (len);
}
static int
writetcp(struct ct_data *ct, caddr_t buf, int len)
{
int i, cnt;
for (cnt = len; cnt > 0; cnt -= i, buf += i) {
if ((i = write(ct->ct_sock, buf, cnt)) == -1) {
ct->ct_error.re_errno = errno;
ct->ct_error.re_status = RPC_CANTSEND;
return (-1);
}
}
return (len);
}