awips2/ldm/src/rpc/svc.c

/* @(#)svc.c	2.4 88/08/11 4.0 RPCSRC; from 1.44 88/02/08 SMI */
/*
 * 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
 */
#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)svc.c 1.41 87/10/13 Copyr 1984 Sun Micro";
#endif

/*
 * svc.c, Server-side remote procedure call interface.
 *
 * There are two sets of procedures here.  The xprt routines are
 * for handling transport handles.  The svc routines handle the
 * list of service routines.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

#include "config.h"

#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sys/errno.h>
#include <sys/time.h>		/* FD_SET, FD_CLR */

#include "rpc.h"
#include "pmap_clnt.h"

extern int errno;

#ifdef FD_SETSIZE
static SVCXPRT **xports;
#else
/*
 * If the following is changed, then modify _rpc_dtablesize() accordingly.
 */
#define NOFILE 32

static SVCXPRT *xports[NOFILE];
#endif /* def FD_SETSIZE */

#define NULL_SVC ((struct svc_callout *)0)
#define	RQCRED_SIZE	400		/* this size is excessive */

/*
 * The services list
 * Each entry represents a set of procedures (an rpc program).
 * The dispatch routine takes request structs and runs the
 * apropriate procedure.
 */
static struct svc_callout {
	struct svc_callout *sc_next;
	unsigned long		    sc_prog;
	unsigned long		    sc_vers;
	void		    (*sc_dispatch)(struct svc_req*, SVCXPRT*);
} *svc_head;

static struct svc_callout *svc_find(
	unsigned long prog,
	unsigned long vers,
	struct svc_callout **prev);

/* ***************  SVCXPRT related stuff **************** */

/*
 * Activate a transport handle.
 */
void
xprt_register(
	SVCXPRT *xprt)
{
	register int sock = xprt->xp_sock;

#ifdef FD_SETSIZE
	if (xports == NULL) {
		xports = (SVCXPRT **)
			mem_alloc(_rpc_dtablesize() * sizeof(SVCXPRT *));
	}
	if (sock < _rpc_dtablesize()) {
		xports[sock] = xprt;
		FD_SET(sock, &svc_fdset);
	}
#else
	if (sock < NOFILE) {
		xports[sock] = xprt;
		svc_fds |= (1 << sock);
	}
#endif /* def FD_SETSIZE */

}

/*
 * De-activate a transport handle. 
 */
void
xprt_unregister(
	SVCXPRT *xprt)
{ 
	register int sock = xprt->xp_sock;

#ifdef FD_SETSIZE
	if ((sock < _rpc_dtablesize()) && (xports[sock] == xprt)) {
		xports[sock] = (SVCXPRT *)0;
		FD_CLR(sock, &svc_fdset);
	}
#else
	if ((sock < NOFILE) && (xports[sock] == xprt)) {
		xports[sock] = (SVCXPRT *)0;
		svc_fds &= ~(1 << sock);
	}
#endif /* def FD_SETSIZE */
}


/* ********************** CALLOUT list related stuff ************* */

/*
 * Add a service program to the callout list.
 * The dispatch routine will be called when a rpc request for this
 * program number comes in.
 */
bool_t
svc_register(
	SVCXPRT *xprt,
	unsigned long prog,
	unsigned long vers,
	void (*dispatch)(),
	int protocol)
{
	struct svc_callout *prev;
	register struct svc_callout *s;

	if ((s = svc_find(prog, vers, &prev)) != NULL_SVC) {
		if (s->sc_dispatch == dispatch)
			goto pmap_it;  /* he is registering another xptr */
		return (FALSE);
	}
	s = (struct svc_callout *)mem_alloc(sizeof(struct svc_callout));
	if (s == (struct svc_callout *)0) {
		return (FALSE);
	}
	s->sc_prog = prog;
	s->sc_vers = vers;
	s->sc_dispatch = dispatch;
	s->sc_next = svc_head;
	svc_head = s;
pmap_it:
	/* now register the information with the local binder service */
	if (protocol) {
		return (pmap_set(prog, vers, protocol, xprt->xp_port));
	}
	return (TRUE);
}

/*
 * Remove a service program from the callout list.
 */
void
svc_unregister(
	unsigned long prog,
	unsigned long vers)
{
	struct svc_callout *prev;
	register struct svc_callout *s;

	if ((s = svc_find(prog, vers, &prev)) == NULL_SVC)
		return;
	if (prev == NULL_SVC) {
		svc_head = s->sc_next;
	} else {
		prev->sc_next = s->sc_next;
	}
	s->sc_next = NULL_SVC;
	mem_free((char *) s, (unsigned) sizeof(struct svc_callout));
	/* now unregister the information with the local binder service */
	(void)pmap_unset(prog, vers);
}

/*
 * Search the callout list for a program number, return the callout
 * struct.
 */
static struct svc_callout *
svc_find(
	unsigned long prog,
	unsigned long vers,
	struct svc_callout **prev)
{
	register struct svc_callout *s, *p;

	p = NULL_SVC;
	for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
		if ((s->sc_prog == prog) && (s->sc_vers == vers))
			goto done;
		p = s;
	}
done:
	*prev = p;
	return (s);
}

/* ******************* REPLY GENERATION ROUTINES  ************ */

/*
 * Send a reply to an rpc request
 */
bool_t
svc_sendreply(
	register SVCXPRT *xprt,
	xdrproc_t xdr_results,
	char* xdr_location)
{
	struct rpc_msg rply; 

	rply.rm_direction = REPLY;  
	rply.rm_reply.rp_stat = MSG_ACCEPTED; 
	rply.acpted_rply.ar_verf = xprt->xp_verf; 
	rply.acpted_rply.ar_stat = SUCCESS;
	rply.acpted_rply.ar_results.where = xdr_location;
	rply.acpted_rply.ar_results.proc = xdr_results;
	return (SVC_REPLY(xprt, &rply)); 
}

/*
 * No procedure error reply
 */
void
svcerr_noproc(
	register SVCXPRT *xprt)
{
	struct rpc_msg rply;

	rply.rm_direction = REPLY;
	rply.rm_reply.rp_stat = MSG_ACCEPTED;
	rply.acpted_rply.ar_verf = xprt->xp_verf;
	rply.acpted_rply.ar_stat = PROC_UNAVAIL;
	SVC_REPLY(xprt, &rply);
}

/*
 * Can't decode args error reply
 */
void
svcerr_decode(
	register SVCXPRT *xprt)
{
	struct rpc_msg rply; 

	rply.rm_direction = REPLY; 
	rply.rm_reply.rp_stat = MSG_ACCEPTED; 
	rply.acpted_rply.ar_verf = xprt->xp_verf;
	rply.acpted_rply.ar_stat = GARBAGE_ARGS;
	SVC_REPLY(xprt, &rply); 
}

/*
 * Some system error
 */
void
svcerr_systemerr(
	register SVCXPRT *xprt)
{
	struct rpc_msg rply; 

	rply.rm_direction = REPLY; 
	rply.rm_reply.rp_stat = MSG_ACCEPTED; 
	rply.acpted_rply.ar_verf = xprt->xp_verf;
	rply.acpted_rply.ar_stat = SYSTEM_ERR;
	SVC_REPLY(xprt, &rply); 
}

/*
 * Authentication error reply
 */
void
svcerr_auth(
	SVCXPRT *xprt,
	enum auth_stat why)
{
	struct rpc_msg rply;

	rply.rm_direction = REPLY;
	rply.rm_reply.rp_stat = MSG_DENIED;
	rply.rjcted_rply.rj_stat = AUTH_ERROR;
	rply.rjcted_rply.rj_why = why;
	SVC_REPLY(xprt, &rply);
}

/*
 * Auth too weak error reply
 */
void
svcerr_weakauth(
	SVCXPRT *xprt)
{

	svcerr_auth(xprt, AUTH_TOOWEAK);
}

/*
 * Program unavailable error reply
 */
void 
svcerr_noprog(
	register SVCXPRT *xprt)
{
	struct rpc_msg rply;  

	rply.rm_direction = REPLY;   
	rply.rm_reply.rp_stat = MSG_ACCEPTED;  
	rply.acpted_rply.ar_verf = xprt->xp_verf;  
	rply.acpted_rply.ar_stat = PROG_UNAVAIL;
	SVC_REPLY(xprt, &rply);
}

/*
 * Program version mismatch error reply
 */
void  
svcerr_progvers(
	register SVCXPRT *xprt, 
	unsigned long low_vers,
	unsigned long high_vers)
{
	struct rpc_msg rply;

	rply.rm_direction = REPLY;
	rply.rm_reply.rp_stat = MSG_ACCEPTED;
	rply.acpted_rply.ar_verf = xprt->xp_verf;
	rply.acpted_rply.ar_stat = PROG_MISMATCH;
	rply.acpted_rply.ar_vers.low = low_vers;
	rply.acpted_rply.ar_vers.high = high_vers;
	SVC_REPLY(xprt, &rply);
}

/* ******************* SERVER INPUT STUFF ******************* */

/*
 * Get server side input from some transport.
 *
 * Statement of authentication parameters management:
 * This function owns and manages all authentication parameters, specifically
 * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
 * the "cooked" credentials (rqst->rq_clntcred).
 * However, this function does not know the structure of the cooked
 * credentials, so it make the following assumptions: 
 *   a) the structure is contiguous (no pointers), and
 *   b) the cred structure size does not exceed RQCRED_SIZE bytes. 
 * In all events, all three parameters are freed upon exit from this routine.
 * The storage is trivially management on the call stack in user land, but
 * is mallocated in kernel land.
 */

void
svc_getreq(
	int rdfds)
{
#ifdef FD_SETSIZE
	fd_set readfds;

	FD_ZERO(&readfds);
	readfds.fds_bits[0] = rdfds;
	svc_getreqset(&readfds);
#else
	int readfds = rdfds & svc_fds;

	svc_getreqset(&readfds);
#endif /* def FD_SETSIZE */
}

#ifdef FD_SETSIZE
void
svc_getreqset(
	fd_set *readfds)
{
#else
void
svc_getreqset(
	int *readfds)
{
	int readfds_local = *readfds;
#endif /* def FD_SETSIZE */
	enum xprt_stat stat;
	struct rpc_msg msg;
	int prog_found;
	unsigned long low_vers;
	unsigned long high_vers;
	struct svc_req r;
	register SVCXPRT *xprt;
	register int sock;
	char cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];
	msg.rm_call.cb_cred.oa_base = cred_area;
	msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
	r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);

#ifdef FD_SETSIZE
	for (sock = 0; sock < FD_SETSIZE; sock++) {
	    if (FD_ISSET(sock, readfds)) {
#else
	for (sock = 0; readfds_local != 0; sock++, readfds_local >>= 1) {
	    if ((readfds_local & 1) != 0) {
#endif /* def FD_SETSIZE */

		/* sock has input waiting */
		xprt = xports[sock];
		/* now receive msgs from xprtprt (support batch calls) */
		do {
			if (SVC_RECV(xprt, &msg)) {

				/* now find the exported program and call it */
				register struct svc_callout *s;
				enum auth_stat why;

				r.rq_xprt = xprt;
				r.rq_prog = msg.rm_call.cb_prog;
				r.rq_vers = msg.rm_call.cb_vers;
				r.rq_proc = msg.rm_call.cb_proc;
				r.rq_cred = msg.rm_call.cb_cred;
				/* first authenticate the message */
				if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
					svcerr_auth(xprt, why);
					goto call_done;
				}
				/* now match message with a registered service*/
				prog_found = FALSE;
				low_vers = (unsigned long)(-1);
				high_vers = 0;
				for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
					if (s->sc_prog == r.rq_prog) {
						if (s->sc_vers == r.rq_vers) {
							(*s->sc_dispatch)(&r, xprt);
							goto call_done;
						}  /* found correct version */
						prog_found = TRUE;
						if (s->sc_vers < low_vers)
							low_vers = s->sc_vers;
						if (s->sc_vers > high_vers)
							high_vers = s->sc_vers;
					}   /* found correct program */
				}
				/*
				 * if we got here, the program or version
				 * is not served ...
				 */
				if (prog_found)
					svcerr_progvers(xprt,
					low_vers, high_vers);
				else
					 svcerr_noprog(xprt);
				/* Fall through to ... */
			}
		call_done:
			if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
				SVC_DESTROY(xprt);
				break;
			}
		} while (stat == XPRT_MOREREQS);
	    }
	}
}


/*
 * Services RPC requests on a single socket.  This is much more
 * efficient than svc_getreqset() for a single socket.
 *
 * Arguments:
 *	sock		The socket on which to service incoming RPC requests.
 */
void
svc_getreqsock(
    int			sock)
{
    enum xprt_stat	stat;
    struct rpc_msg	msg;
    int			prog_found;
    unsigned long	low_vers;
    unsigned long	high_vers;
    struct svc_req	r;
    register SVCXPRT*	xprt;
    char		cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];

    msg.rm_call.cb_cred.oa_base = cred_area;
    msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
    r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);

    /* sock has input waiting */
    xprt = xports[sock];

    /* now receive msgs from xprtprt (support batch calls) */
    do {
	if (SVC_RECV(xprt, &msg)) {
	    /* now find the exported program and call it */
	    register struct svc_callout *s;
	    enum auth_stat why;

	    r.rq_xprt = xprt;
	    r.rq_prog = msg.rm_call.cb_prog;
	    r.rq_vers = msg.rm_call.cb_vers;
	    r.rq_proc = msg.rm_call.cb_proc;
	    r.rq_cred = msg.rm_call.cb_cred;

	    /* first authenticate the message */
	    if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
		svcerr_auth(xprt, why);
		goto call_done;
	    }

	    /* now match message with a registered service*/
	    prog_found = FALSE;
	    low_vers = (unsigned long)(-1);
	    high_vers = 0;
	    for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
		if (s->sc_prog == r.rq_prog) {
		    if (s->sc_vers == r.rq_vers) {
			(*s->sc_dispatch)(&r, xprt);
			goto call_done;
		    }  /* found correct version */
		    prog_found = TRUE;
		    if (s->sc_vers < low_vers)
			low_vers = s->sc_vers;
		    if (s->sc_vers > high_vers)
			high_vers = s->sc_vers;
		}   /* found correct program */
	    }
	    /*
	     * if we got here, the program or version is not served ...
	     */
	    if (prog_found) {
		svcerr_progvers(xprt,
		low_vers, high_vers);
	    }
	    else {
		 svcerr_noprog(xprt);
	    }

	    /* Fall through to ... */
	}
    call_done:
	if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
	    SVC_DESTROY(xprt);
	    break;
	}
    } while (stat == XPRT_MOREREQS);
}