Home | History | Annotate | Line # | Download | only in rpcbind
rpcb_svc_com.c revision 1.20.4.1
      1 /*	$NetBSD: rpcb_svc_com.c,v 1.20.4.1 2019/06/10 22:10:36 christos Exp $	*/
      2 /*	$FreeBSD: head/usr.sbin/rpcbind/rpcb_svc_com.c 301770 2016-06-09 22:25:00Z pfg $ */
      3 
      4 /*-
      5  * Copyright (c) 2009, Sun Microsystems, Inc.
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions are met:
     10  * - Redistributions of source code must retain the above copyright notice,
     11  *   this list of conditions and the following disclaimer.
     12  * - Redistributions in binary form must reproduce the above copyright notice,
     13  *   this list of conditions and the following disclaimer in the documentation
     14  *   and/or other materials provided with the distribution.
     15  * - Neither the name of Sun Microsystems, Inc. nor the names of its
     16  *   contributors may be used to endorse or promote products derived
     17  *   from this software without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
     20  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
     23  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 /*
     32  * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
     33  */
     34 
     35 /* #ident	"@(#)rpcb_svc_com.c	1.18	94/05/02 SMI" */
     36 
     37 /*
     38  * rpcb_svc_com.c
     39  * The commom server procedure for the rpcbind.
     40  */
     41 
     42 #include <sys/types.h>
     43 #include <sys/stat.h>
     44 #include <sys/param.h>
     45 #include <sys/socket.h>
     46 #include <rpc/rpc.h>
     47 #include <rpc/rpcb_prot.h>
     48 #include <rpc/rpc_com.h>
     49 #include <assert.h>
     50 #include <netconfig.h>
     51 #include <errno.h>
     52 #include <syslog.h>
     53 #include <unistd.h>
     54 #include <stdio.h>
     55 #include <poll.h>
     56 #ifdef PORTMAP
     57 #include <netinet/in.h>
     58 #include <rpc/pmap_prot.h>
     59 #endif /* PORTMAP */
     60 #include <string.h>
     61 #include <stdlib.h>
     62 
     63 #ifdef RPCBIND_RUMP
     64 #include <rump/rump.h>
     65 #include <rump/rump_syscalls.h>
     66 #endif
     67 
     68 #include "svc_dg.h"
     69 #include "rpcbind.h"
     70 #ifdef RPCBIND_RUMP
     71 #include "svc_fdset.h"
     72 #endif
     73 
     74 #define RPC_BUF_MAX	65536	/* can be raised if required */
     75 
     76 static char nullstring[] = "";
     77 static int rpcb_rmtcalls;
     78 
     79 struct rmtcallfd_list {
     80 	int fd;
     81 	SVCXPRT *xprt;
     82 	char *netid;
     83 	struct rmtcallfd_list *next;
     84 };
     85 
     86 #define NFORWARD        64
     87 #define MAXTIME_OFF     300     /* 5 minutes */
     88 
     89 struct finfo {
     90 	int             flag;
     91 #define FINFO_ACTIVE    0x1
     92 	u_int32_t       caller_xid;
     93         struct netbuf   *caller_addr;
     94 	u_int32_t       forward_xid;
     95 	int             forward_fd;
     96 	char            *uaddr;
     97 	rpcproc_t       reply_type;
     98 	rpcvers_t       versnum;
     99 	time_t          time;
    100 };
    101 static struct finfo     FINFO[NFORWARD];
    102 
    103 
    104 static bool_t xdr_encap_parms(XDR *, struct encap_parms *);
    105 static bool_t xdr_rmtcall_args(XDR *, struct r_rmtcall_args *);
    106 static bool_t xdr_rmtcall_result(XDR *, struct r_rmtcall_args *);
    107 static bool_t xdr_opaque_parms(XDR *, struct r_rmtcall_args *);
    108 static int find_rmtcallfd_by_netid(char *);
    109 static SVCXPRT *find_rmtcallxprt_by_fd(int);
    110 static int forward_register(u_int32_t, struct netbuf *, int, char *,
    111     rpcproc_t, rpcvers_t, u_int32_t *);
    112 static struct finfo *forward_find(u_int32_t);
    113 static int free_slot_by_xid(u_int32_t);
    114 static int free_slot_by_index(int);
    115 static int netbufcmp(struct netbuf *, struct netbuf *);
    116 static struct netbuf *netbufdup(struct netbuf *);
    117 static void netbuffree(struct netbuf *);
    118 static int check_rmtcalls(struct pollfd *, int);
    119 static void xprt_set_caller(SVCXPRT *, struct finfo *);
    120 static void send_svcsyserr(SVCXPRT *, struct finfo *);
    121 static void handle_reply(int, SVCXPRT *);
    122 static void find_versions(rpcprog_t, char *, rpcvers_t *, rpcvers_t *);
    123 static rpcblist_ptr find_service(rpcprog_t, rpcvers_t, char *);
    124 static char *getowner(SVCXPRT *, char *, size_t);
    125 static int add_pmaplist(RPCB *);
    126 static int del_pmaplist(RPCB *);
    127 
    128 /*
    129  * Set a mapping of program, version, netid
    130  */
    131 /* ARGSUSED */
    132 void *
    133 rpcbproc_set_com(void *arg, struct svc_req *rqstp __unused, SVCXPRT *transp,
    134 		 rpcvers_t rpcbversnum)
    135 {
    136 	RPCB *regp = arg;
    137 	static bool_t ans;
    138 	char owner[64];
    139 
    140 #ifdef RPCBIND_DEBUG
    141 	if (debugging)
    142 		fprintf(stderr, "RPCB_SET request for (%lu, %lu, %s, %s) : ",
    143 		    (unsigned long)regp->r_prog, (unsigned long)regp->r_vers,
    144 		    regp->r_netid, regp->r_addr);
    145 #endif
    146 	ans = map_set(regp, getowner(transp, owner, sizeof owner));
    147 #ifdef RPCBIND_DEBUG
    148 	if (debugging)
    149 		fprintf(stderr, "%s\n", ans == TRUE ? "succeeded" : "failed");
    150 #endif
    151 	/* XXX: should have used some defined constant here */
    152 	rpcbs_set(rpcbversnum - 2, ans);
    153 	return (void *)&ans;
    154 }
    155 
    156 bool_t
    157 map_set(RPCB *regp, char *owner)
    158 {
    159 	RPCB reg, *a;
    160 	rpcblist_ptr rbl, fnd;
    161 
    162 	reg = *regp;
    163 	/*
    164 	 * check to see if already used
    165 	 * find_service returns a hit even if
    166 	 * the versions don't match, so check for it
    167 	 */
    168 	fnd = find_service(reg.r_prog, reg.r_vers, reg.r_netid);
    169 	if (fnd && (fnd->rpcb_map.r_vers == reg.r_vers)) {
    170 		if (!strcmp(fnd->rpcb_map.r_addr, reg.r_addr))
    171 			/*
    172 			 * if these match then it is already
    173 			 * registered so just say "OK".
    174 			 */
    175 			return (TRUE);
    176 		else
    177 			return (FALSE);
    178 	}
    179 	/*
    180 	 * add to the end of the list
    181 	 */
    182 	rbl = malloc(sizeof(*rbl));
    183 	if (rbl == NULL)
    184 		return (FALSE);
    185 	a = &(rbl->rpcb_map);
    186 	a->r_prog = reg.r_prog;
    187 	a->r_vers = reg.r_vers;
    188 	a->r_netid = strdup(reg.r_netid);
    189 	a->r_addr = strdup(reg.r_addr);
    190 	a->r_owner = strdup(owner);
    191 	if (!a->r_addr || !a->r_netid || !a->r_owner) {
    192 		if (a->r_netid)
    193 			free(a->r_netid);
    194 		if (a->r_addr)
    195 			free(a->r_addr);
    196 		if (a->r_owner)
    197 			free(a->r_owner);
    198 		free(rbl);
    199 		return (FALSE);
    200 	}
    201 	rbl->rpcb_next = NULL;
    202 	if (list_rbl == NULL) {
    203 		list_rbl = rbl;
    204 	} else {
    205 		for (fnd = list_rbl; fnd->rpcb_next;
    206 			fnd = fnd->rpcb_next)
    207 			;
    208 		fnd->rpcb_next = rbl;
    209 	}
    210 #ifdef PORTMAP
    211 	(void) add_pmaplist(regp);
    212 #endif
    213 	return (TRUE);
    214 }
    215 
    216 /*
    217  * Unset a mapping of program, version, netid
    218  */
    219 /* ARGSUSED */
    220 void *
    221 rpcbproc_unset_com(void *arg, struct svc_req *rqstp __unused, SVCXPRT *transp,
    222 		   rpcvers_t rpcbversnum)
    223 {
    224 	RPCB *regp = arg;
    225 	static bool_t ans;
    226 	char owner[64];
    227 
    228 #ifdef RPCBIND_DEBUG
    229 	if (debugging)
    230 		fprintf(stderr, "RPCB_UNSET request for (%lu, %lu, %s) : ",
    231 		    (unsigned long)regp->r_prog, (unsigned long)regp->r_vers,
    232 		    regp->r_netid);
    233 #endif
    234 	ans = map_unset(regp, getowner(transp, owner, sizeof owner));
    235 #ifdef RPCBIND_DEBUG
    236 	if (debugging)
    237 		fprintf(stderr, "%s\n", ans == TRUE ? "succeeded" : "failed");
    238 #endif
    239 	/* XXX: should have used some defined constant here */
    240 	rpcbs_unset(rpcbversnum - 2, ans);
    241 	return (void *)&ans;
    242 }
    243 
    244 bool_t
    245 map_unset(RPCB *regp, const char *owner)
    246 {
    247 	int ans = 0;
    248 	rpcblist_ptr rbl, prev, tmp;
    249 
    250 	if (owner == NULL)
    251 		return (0);
    252 
    253 	for (prev = NULL, rbl = list_rbl; rbl; /* cstyle */) {
    254 		if ((rbl->rpcb_map.r_prog != regp->r_prog) ||
    255 			(rbl->rpcb_map.r_vers != regp->r_vers) ||
    256 			(regp->r_netid[0] && strcasecmp(regp->r_netid,
    257 				rbl->rpcb_map.r_netid))) {
    258 			/* both rbl & prev move forwards */
    259 			prev = rbl;
    260 			rbl = rbl->rpcb_next;
    261 			continue;
    262 		}
    263 		/*
    264 		 * Check whether appropriate uid. Unset only
    265 		 * if superuser or the owner itself.
    266 		 */
    267 		if (strcmp(owner, rpcbind_superuser) &&
    268 			strcmp(rbl->rpcb_map.r_owner, owner))
    269 			return (0);
    270 		/* found it; rbl moves forward, prev stays */
    271 		ans = 1;
    272 		tmp = rbl;
    273 		rbl = rbl->rpcb_next;
    274 		if (prev == NULL)
    275 			list_rbl = rbl;
    276 		else
    277 			prev->rpcb_next = rbl;
    278 		free(tmp->rpcb_map.r_addr);
    279 		free(tmp->rpcb_map.r_netid);
    280 		free(tmp->rpcb_map.r_owner);
    281 		free(tmp);
    282 	}
    283 #ifdef PORTMAP
    284 	if (ans)
    285 		(void) del_pmaplist(regp);
    286 #endif
    287 	/*
    288 	 * We return 1 either when the entry was not there or it
    289 	 * was able to unset it.  It can come to this point only if
    290 	 * atleast one of the conditions is true.
    291 	 */
    292 	return (1);
    293 }
    294 
    295 void
    296 delete_prog(rpcprog_t prog)
    297 {
    298 	RPCB reg;
    299 	rpcblist_ptr rbl;
    300 
    301 	for (rbl = list_rbl; rbl != NULL; rbl = rbl->rpcb_next) {
    302 		if ((rbl->rpcb_map.r_prog != prog))
    303 			continue;
    304 		if (is_bound(rbl->rpcb_map.r_netid, rbl->rpcb_map.r_addr))
    305 			continue;
    306 		reg.r_prog = rbl->rpcb_map.r_prog;
    307 		reg.r_vers = rbl->rpcb_map.r_vers;
    308 		reg.r_netid = strdup(rbl->rpcb_map.r_netid);
    309 		if (reg.r_netid == NULL)
    310 			syslog(LOG_ERR, "%s: Cannot allocate memory", __func__);
    311 		else {
    312 			(void)map_unset(&reg, rpcbind_superuser);
    313 			free(reg.r_netid);
    314 		}
    315 	}
    316 }
    317 
    318 void *
    319 rpcbproc_getaddr_com(RPCB *regp, struct svc_req *rqstp __unused,
    320     SVCXPRT *transp, rpcvers_t rpcbversnum, rpcvers_t verstype)
    321 {
    322 	static char *uaddr;
    323 	char *saddr = NULL;
    324 	rpcblist_ptr fnd;
    325 
    326 	if (uaddr != NULL && uaddr != nullstring) {
    327 		free(uaddr);
    328 		uaddr = NULL;
    329 	}
    330 	fnd = find_service(regp->r_prog, regp->r_vers, transp->xp_netid);
    331 	if (fnd && ((verstype == RPCB_ALLVERS) ||
    332 		    (regp->r_vers == fnd->rpcb_map.r_vers))) {
    333 		if (*(regp->r_addr) != '\0') {  /* may contain a hint about */
    334 			saddr = regp->r_addr;   /* the interface that we    */
    335 		}				/* should use */
    336 		if (!(uaddr = mergeaddr(transp, transp->xp_netid,
    337 				fnd->rpcb_map.r_addr, saddr))) {
    338 			/* Try whatever we have */
    339 			uaddr = strdup(fnd->rpcb_map.r_addr);
    340 		} else if (!uaddr[0]) {
    341 			/*
    342 			 * The server died.  Unset all versions of this prog.
    343 			 */
    344 			delete_prog(regp->r_prog);
    345 			uaddr = nullstring;
    346 		}
    347 	} else {
    348 		uaddr = nullstring;
    349 	}
    350 #ifdef RPCBIND_DEBUG
    351 	if (debugging)
    352 		fprintf(stderr, "getaddr: %s\n", uaddr);
    353 #endif
    354 	/* XXX: should have used some defined constant here */
    355 	rpcbs_getaddr(rpcbversnum - 2, regp->r_prog, regp->r_vers,
    356 		transp->xp_netid, uaddr);
    357 	return (void *)&uaddr;
    358 }
    359 
    360 /* ARGSUSED */
    361 void *
    362 rpcbproc_gettime_com(void *arg __unused, struct svc_req *rqstp __unused,
    363     SVCXPRT *transp __unused, rpcvers_t rpcbversnum __unused)
    364 {
    365 	static time_t curtime;
    366 
    367 	(void) time(&curtime);
    368 	return &curtime;
    369 }
    370 
    371 /*
    372  * Convert uaddr to taddr. Should be used only by
    373  * local servers/clients. (kernel level stuff only)
    374  */
    375 /* ARGSUSED */
    376 void *
    377 rpcbproc_uaddr2taddr_com(void *arg, struct svc_req *rqstp __unused,
    378     SVCXPRT *transp, rpcvers_t rpcbversnum __unused)
    379 {
    380 	char **uaddrp = arg;
    381 	struct netconfig *nconf;
    382 	static struct netbuf nbuf;
    383 	static struct netbuf *taddr;
    384 
    385 	if (taddr) {
    386 		free(taddr->buf);
    387 		free(taddr);
    388 		taddr = NULL;
    389 	}
    390 	if (((nconf = rpcbind_get_conf(transp->xp_netid)) == NULL) ||
    391 	    ((taddr = uaddr2taddr(nconf, *uaddrp)) == NULL)) {
    392 		(void) memset(&nbuf, 0, sizeof (struct netbuf));
    393 		return &nbuf;
    394 	}
    395 	return taddr;
    396 }
    397 
    398 /*
    399  * Convert taddr to uaddr. Should be used only by
    400  * local servers/clients. (kernel level stuff only)
    401  */
    402 /* ARGSUSED */
    403 void *
    404 rpcbproc_taddr2uaddr_com(void *arg, struct svc_req *rqstp __unused,
    405     SVCXPRT *transp, rpcvers_t rpcbversnum __unused)
    406 {
    407 	struct netbuf *taddr = arg;
    408 	static char *uaddr;
    409 	struct netconfig *nconf;
    410 
    411 #ifdef CHEW_FDS
    412 	int fd;
    413 
    414 	if ((fd = open("/dev/null", O_RDONLY)) == -1) {
    415 		uaddr = strerror(errno);
    416 		return (&uaddr);
    417 	}
    418 #endif /* CHEW_FDS */
    419 	if (uaddr != NULL && uaddr != nullstring) {
    420 		free(uaddr);
    421 		uaddr = NULL;
    422 	}
    423 	if (((nconf = rpcbind_get_conf(transp->xp_netid)) == NULL) ||
    424 		((uaddr = taddr2uaddr(nconf, taddr)) == NULL)) {
    425 		uaddr = nullstring;
    426 	}
    427 	return (void *)&uaddr;
    428 }
    429 
    430 
    431 static bool_t
    432 xdr_encap_parms(XDR *xdrs, struct encap_parms *epp)
    433 {
    434 	return (xdr_bytes(xdrs, &(epp->args), (u_int *) &(epp->arglen),
    435 	    RPC_MAXDATASIZE));
    436 }
    437 
    438 /*
    439  * XDR remote call arguments.  It ignores the address part.
    440  * written for XDR_DECODE direction only
    441  */
    442 static bool_t
    443 xdr_rmtcall_args(XDR *xdrs, struct r_rmtcall_args *cap)
    444 {
    445 	/* does not get the address or the arguments */
    446 	if (xdr_rpcprog(xdrs, &(cap->rmt_prog)) &&
    447 	    xdr_rpcvers(xdrs, &(cap->rmt_vers)) &&
    448 	    xdr_rpcproc(xdrs, &(cap->rmt_proc))) {
    449 		return (xdr_encap_parms(xdrs, &(cap->rmt_args)));
    450 	}
    451 	return (FALSE);
    452 }
    453 
    454 /*
    455  * XDR remote call results along with the address.  Ignore
    456  * program number, version  number and proc number.
    457  * Written for XDR_ENCODE direction only.
    458  */
    459 static bool_t
    460 xdr_rmtcall_result(XDR *xdrs, struct r_rmtcall_args *cap)
    461 {
    462 	bool_t result;
    463 
    464 #ifdef PORTMAP
    465 	if (cap->rmt_localvers == PMAPVERS) {
    466 		int h1, h2, h3, h4, p1, p2;
    467 		u_long port;
    468 
    469 		/* interpret the universal address for TCP/IP */
    470 		if (sscanf(cap->rmt_uaddr, "%d.%d.%d.%d.%d.%d",
    471 			&h1, &h2, &h3, &h4, &p1, &p2) != 6)
    472 			return (FALSE);
    473 		port = ((p1 & 0xff) << 8) + (p2 & 0xff);
    474 		result = xdr_u_long(xdrs, &port);
    475 	} else
    476 #endif
    477 		if ((cap->rmt_localvers == RPCBVERS) ||
    478 		    (cap->rmt_localvers == RPCBVERS4)) {
    479 		result = xdr_wrapstring(xdrs, &(cap->rmt_uaddr));
    480 	} else {
    481 		return (FALSE);
    482 	}
    483 	if (result == TRUE)
    484 		return (xdr_encap_parms(xdrs, &(cap->rmt_args)));
    485 	return (FALSE);
    486 }
    487 
    488 /*
    489  * only worries about the struct encap_parms part of struct r_rmtcall_args.
    490  * The arglen must already be set!!
    491  */
    492 static bool_t
    493 xdr_opaque_parms(XDR *xdrs, struct r_rmtcall_args *cap)
    494 {
    495 	return (xdr_opaque(xdrs, cap->rmt_args.args, cap->rmt_args.arglen));
    496 }
    497 
    498 static struct rmtcallfd_list *rmthead;
    499 static struct rmtcallfd_list *rmttail;
    500 
    501 int
    502 create_rmtcall_fd(struct netconfig *nconf)
    503 {
    504 	int fd;
    505 	struct rmtcallfd_list *rmt;
    506 	SVCXPRT *xprt;
    507 
    508 	if ((fd = __rpc_nconf2fd(nconf)) == -1) {
    509 		if (debugging)
    510 			fprintf(stderr,
    511 	"create_rmtcall_fd: couldn't open \"%s\" (errno %d)\n",
    512 			nconf->nc_device, errno);
    513 		return (-1);
    514 	}
    515 	xprt = svc_tli_create(fd, 0, NULL, 0, 0);
    516 	if (xprt == NULL) {
    517 		if (debugging)
    518 			fprintf(stderr,
    519 				"%s: svc_tli_create failed\n", __func__);
    520 		return (-1);
    521 	}
    522 	rmt = malloc(sizeof(*rmt));
    523 	if (rmt == NULL) {
    524 		syslog(LOG_ERR, "%s: Cannot allocate memory", __func__);
    525 		return (-1);
    526 	}
    527 	rmt->xprt = xprt;
    528 	rmt->netid = strdup(nconf->nc_netid);
    529 	xprt->xp_netid = rmt->netid;
    530 	rmt->fd = fd;
    531 	rmt->next = NULL;
    532 	if (rmthead == NULL) {
    533 		rmthead = rmt;
    534 		rmttail = rmt;
    535 	} else {
    536 		rmttail->next = rmt;
    537 		rmttail = rmt;
    538 	}
    539 	svc_fdset_set(fd);
    540 	return (fd);
    541 }
    542 
    543 static int
    544 find_rmtcallfd_by_netid(char *netid)
    545 {
    546 	struct rmtcallfd_list *rmt;
    547 
    548 	for (rmt = rmthead; rmt != NULL; rmt = rmt->next) {
    549 		if (strcmp(netid, rmt->netid) == 0) {
    550 			return (rmt->fd);
    551 		}
    552 	}
    553 	return (-1);
    554 }
    555 
    556 static SVCXPRT *
    557 find_rmtcallxprt_by_fd(int fd)
    558 {
    559 	struct rmtcallfd_list *rmt;
    560 
    561 	for (rmt = rmthead; rmt != NULL; rmt = rmt->next) {
    562 		if (fd == rmt->fd) {
    563 			return (rmt->xprt);
    564 		}
    565 	}
    566 	return (NULL);
    567 }
    568 
    569 
    570 /*
    571  * Call a remote procedure service.  This procedure is very quiet when things
    572  * go wrong.  The proc is written to support broadcast rpc.  In the broadcast
    573  * case, a machine should shut-up instead of complain, lest the requestor be
    574  * overrun with complaints at the expense of not hearing a valid reply.
    575  * When receiving a request and verifying that the service exists, we
    576  *
    577  *	receive the request
    578  *
    579  *	open a new TLI endpoint on the same transport on which we received
    580  *	the original request
    581  *
    582  *	remember the original request's XID (which requires knowing the format
    583  *	of the svc_dg_data structure)
    584  *
    585  *	forward the request, with a new XID, to the requested service,
    586  *	remembering the XID used to send this request (for later use in
    587  *	reassociating the answer with the original request), the requestor's
    588  *	address, the file descriptor on which the forwarded request is
    589  *	made and the service's address.
    590  *
    591  *	mark the file descriptor on which we anticipate receiving a reply from
    592  *	the service and one to select for in our private svc_run procedure
    593  *
    594  * At some time in the future, a reply will be received from the service to
    595  * which we forwarded the request.  At that time, we detect that the socket
    596  * used was for forwarding (by looking through the finfo structures to see
    597  * whether the fd corresponds to one of those) and call handle_reply() to
    598  *
    599  *	receive the reply
    600  *
    601  *	bundle the reply, along with the service's universal address
    602  *
    603  *	create a SVCXPRT structure and use a version of svc_sendreply
    604  *	that allows us to specify the reply XID and destination, send the reply
    605  *	to the original requestor.
    606  */
    607 
    608 void
    609 rpcbproc_callit_com(struct svc_req *rqstp, SVCXPRT *transp,
    610 		    rpcproc_t reply_type, rpcvers_t versnum)
    611 {
    612 	rpcblist_ptr rbl;
    613 	struct netconfig *nconf;
    614 	struct netbuf *caller;
    615 	struct r_rmtcall_args a;
    616 	char *buf_alloc = NULL, *outbufp;
    617 	char *outbuf_alloc = NULL;
    618 	char buf[RPC_BUF_MAX], outbuf[RPC_BUF_MAX];
    619 	struct netbuf *na = NULL;
    620 	struct rpc_msg call_msg;
    621 	int outlen;
    622 	u_int sendsz;
    623 	XDR outxdr;
    624 	AUTH *auth;
    625 	int fd = -1;
    626 	char *uaddr, *m_uaddr = NULL, *local_uaddr = NULL;
    627 	u_int32_t *xidp;
    628 	struct __rpc_sockinfo si;
    629 	struct sockaddr *localsa;
    630 	struct netbuf tbuf;
    631 
    632 	if (!__rpc_fd2sockinfo(transp->xp_fd, &si)) {
    633 		if (reply_type == RPCBPROC_INDIRECT)
    634 			svcerr_systemerr(transp);
    635 		return;
    636 	}
    637 	if (si.si_socktype != SOCK_DGRAM)
    638 		return;	/* Only datagram type accepted */
    639 	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, UDPMSGSIZE);
    640 	if (sendsz == 0) {	/* data transfer not supported */
    641 		if (reply_type == RPCBPROC_INDIRECT)
    642 			svcerr_systemerr(transp);
    643 		return;
    644 	}
    645 	/*
    646 	 * Should be multiple of 4 for XDR.
    647 	 */
    648 	sendsz = roundup(sendsz, 4);
    649 	if (sendsz > RPC_BUF_MAX) {
    650 #ifdef	notyet
    651 		buf_alloc = alloca(sendsz);		/* not in IDR2? */
    652 #else
    653 		buf_alloc = malloc(sendsz);
    654 #endif	/* notyet */
    655 		if (buf_alloc == NULL) {
    656 			if (debugging)
    657 				fprintf(stderr,
    658 					"rpcbproc_callit_com:  No Memory!\n");
    659 			if (reply_type == RPCBPROC_INDIRECT)
    660 				svcerr_systemerr(transp);
    661 			return;
    662 		}
    663 		a.rmt_args.args = buf_alloc;
    664 	} else {
    665 		a.rmt_args.args = buf;
    666 	}
    667 
    668 	call_msg.rm_xid = 0;	/* For error checking purposes */
    669 	if (!svc_getargs(transp, (xdrproc_t) xdr_rmtcall_args, (char *) &a)) {
    670 		if (reply_type == RPCBPROC_INDIRECT)
    671 			svcerr_decode(transp);
    672 		if (debugging)
    673 			fprintf(stderr,
    674 			"rpcbproc_callit_com:  svc_getargs failed\n");
    675 		goto error;
    676 	}
    677 
    678 	if (!check_callit(transp, &a, versnum)) {
    679 		svcerr_weakauth(transp);
    680 		goto error;
    681 	}
    682 
    683 	caller = svc_getrpccaller(transp);
    684 #ifdef RPCBIND_DEBUG
    685 	if (debugging) {
    686 		uaddr = taddr2uaddr(rpcbind_get_conf(transp->xp_netid), caller);
    687 		fprintf(stderr, "%s %s req for (%lu, %lu, %lu, %s) from %s : ",
    688 			versnum == PMAPVERS ? "pmap_rmtcall" :
    689 			versnum == RPCBVERS ? "rpcb_rmtcall" :
    690 			versnum == RPCBVERS4 ? "rpcb_indirect" :
    691 			rpcbind_unknown,
    692 			reply_type == RPCBPROC_INDIRECT ? "indirect" : "callit",
    693 			(unsigned long)a.rmt_prog, (unsigned long)a.rmt_vers,
    694 			(unsigned long)a.rmt_proc, transp->xp_netid,
    695 			uaddr ? uaddr : rpcbind_unknown);
    696 		if (uaddr)
    697 			free(uaddr);
    698 	}
    699 #endif
    700 
    701 	rbl = find_service(a.rmt_prog, a.rmt_vers, transp->xp_netid);
    702 
    703 	rpcbs_rmtcall(versnum - 2, reply_type, a.rmt_prog, a.rmt_vers,
    704 			a.rmt_proc, transp->xp_netid, rbl);
    705 
    706 	if (rbl == NULL) {
    707 #ifdef RPCBIND_DEBUG
    708 		if (debugging)
    709 			fprintf(stderr, "not found\n");
    710 #endif
    711 		if (reply_type == RPCBPROC_INDIRECT)
    712 			svcerr_noprog(transp);
    713 		goto error;
    714 	}
    715 	if (rbl->rpcb_map.r_vers != a.rmt_vers) {
    716 		if (reply_type == RPCBPROC_INDIRECT) {
    717 			rpcvers_t vers_low, vers_high;
    718 
    719 			find_versions(a.rmt_prog, transp->xp_netid,
    720 				&vers_low, &vers_high);
    721 			svcerr_progvers(transp, vers_low, vers_high);
    722 		}
    723 		goto error;
    724 	}
    725 
    726 #ifdef RPCBIND_DEBUG
    727 	if (debugging)
    728 		fprintf(stderr, "found at uaddr %s\n", rbl->rpcb_map.r_addr);
    729 #endif
    730 	/*
    731 	 *	Check whether this entry is valid and a server is present
    732 	 *	Mergeaddr() returns NULL if no such entry is present, and
    733 	 *	returns "" if the entry was present but the server is not
    734 	 *	present (i.e., it crashed).
    735 	 */
    736 	if (reply_type == RPCBPROC_INDIRECT) {
    737 		uaddr = mergeaddr(transp, transp->xp_netid,
    738 			rbl->rpcb_map.r_addr, NULL);
    739 		if (uaddr == NULL || uaddr[0] == '\0') {
    740 			svcerr_noprog(transp);
    741 			free(uaddr);
    742 			goto error;
    743 		}
    744 		free(uaddr);
    745 	}
    746 	nconf = rpcbind_get_conf(transp->xp_netid);
    747 	if (nconf == NULL) {
    748 		if (reply_type == RPCBPROC_INDIRECT)
    749 			svcerr_systemerr(transp);
    750 		if (debugging)
    751 			fprintf(stderr,
    752 			"rpcbproc_callit_com:  rpcbind_get_conf failed\n");
    753 		goto error;
    754 	}
    755 	localsa = local_sa(((struct sockaddr *)caller->buf)->sa_family);
    756 	if (localsa == NULL) {
    757 		if (debugging)
    758 			fprintf(stderr,
    759 			"rpcbproc_callit_com: no local address\n");
    760 		goto error;
    761 	}
    762 	tbuf.len = tbuf.maxlen = localsa->sa_len;
    763 	tbuf.buf = localsa;
    764 	local_uaddr =
    765 	    addrmerge(&tbuf, rbl->rpcb_map.r_addr, NULL, nconf->nc_netid);
    766 	m_uaddr = addrmerge(caller, rbl->rpcb_map.r_addr, NULL,
    767 			nconf->nc_netid);
    768 #ifdef RPCBIND_DEBUG
    769 	if (debugging)
    770 		fprintf(stderr, "merged uaddr %s\n", m_uaddr);
    771 #endif
    772 	if ((fd = find_rmtcallfd_by_netid(nconf->nc_netid)) == -1) {
    773 		if (reply_type == RPCBPROC_INDIRECT)
    774 			svcerr_systemerr(transp);
    775 		goto error;
    776 	}
    777 	xidp = __rpcb_get_dg_xidp(transp);
    778 	switch (forward_register(*xidp, caller, fd, m_uaddr, reply_type,
    779 	    versnum, &call_msg.rm_xid)) {
    780 	case 1:
    781 		/* Success; forward_register() will free m_uaddr for us. */
    782 		m_uaddr = NULL;
    783 		break;
    784 	case 0:
    785 		/*
    786 		 * A duplicate request for the slow server.  Let's not
    787 		 * beat on it any more.
    788 		 */
    789 		if (debugging)
    790 			fprintf(stderr,
    791 			"rpcbproc_callit_com:  duplicate request\n");
    792 		goto error;
    793 	case -1:
    794 		/*  forward_register failed.  Perhaps no memory. */
    795 		if (debugging)
    796 			fprintf(stderr,
    797 			"rpcbproc_callit_com:  forward_register failed\n");
    798 		goto error;
    799 	}
    800 
    801 #ifdef DEBUG_RMTCALL
    802 	if (debugging)
    803 		fprintf(stderr,
    804 			"rpcbproc_callit_com:  original XID %x, new XID %x\n",
    805 				*xidp, call_msg.rm_xid);
    806 #endif
    807 	call_msg.rm_direction = CALL;
    808 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
    809 	call_msg.rm_call.cb_prog = a.rmt_prog;
    810 	call_msg.rm_call.cb_vers = a.rmt_vers;
    811 	if (sendsz > RPC_BUF_MAX) {
    812 #ifdef	notyet
    813 		outbuf_alloc = alloca(sendsz);	/* not in IDR2? */
    814 #else
    815 		outbuf_alloc = malloc(sendsz);
    816 #endif	/* notyet */
    817 		if (outbuf_alloc == NULL) {
    818 			if (reply_type == RPCBPROC_INDIRECT)
    819 				svcerr_systemerr(transp);
    820 			syslog(LOG_ERR, "%s: Cannot allocate memory", __func__);
    821 			goto error;
    822 		}
    823 		xdrmem_create(&outxdr, outbuf_alloc, sendsz, XDR_ENCODE);
    824 	} else {
    825 		xdrmem_create(&outxdr, outbuf, sendsz, XDR_ENCODE);
    826 	}
    827 	if (!xdr_callhdr(&outxdr, &call_msg)) {
    828 		if (reply_type == RPCBPROC_INDIRECT)
    829 			svcerr_systemerr(transp);
    830 		if (debugging)
    831 			fprintf(stderr,
    832 			"rpcbproc_callit_com:  xdr_callhdr failed\n");
    833 		goto error;
    834 	}
    835 	if (!xdr_u_int32_t(&outxdr, &(a.rmt_proc))) {
    836 		if (reply_type == RPCBPROC_INDIRECT)
    837 			svcerr_systemerr(transp);
    838 		if (debugging)
    839 			fprintf(stderr,
    840 			"rpcbproc_callit_com:  xdr_u_long failed\n");
    841 		goto error;
    842 	}
    843 
    844 	if (rqstp->rq_cred.oa_flavor == AUTH_NULL) {
    845 		auth = authnone_create();
    846 	} else if (rqstp->rq_cred.oa_flavor == AUTH_SYS) {
    847 		struct authunix_parms *au;
    848 
    849 		au = (struct authunix_parms *)rqstp->rq_clntcred;
    850 		auth = authunix_create(au->aup_machname,
    851 				au->aup_uid, au->aup_gid,
    852 				au->aup_len, au->aup_gids);
    853 		if (auth == NULL) /* fall back */
    854 			auth = authnone_create();
    855 	} else {
    856 		/* we do not support any other authentication scheme */
    857 		if (debugging)
    858 			fprintf(stderr,
    859 "rpcbproc_callit_com:  oa_flavor != AUTH_NONE and oa_flavor != AUTH_SYS\n");
    860 		if (reply_type == RPCBPROC_INDIRECT)
    861 			svcerr_weakauth(transp); /* XXX too strong.. */
    862 		goto error;
    863 	}
    864 	if (auth == NULL) {
    865 		if (reply_type == RPCBPROC_INDIRECT)
    866 			svcerr_systemerr(transp);
    867 		if (debugging)
    868 			fprintf(stderr,
    869 		"rpcbproc_callit_com:  authwhatever_create returned NULL\n");
    870 		goto error;
    871 	}
    872 	if (!AUTH_MARSHALL(auth, &outxdr)) {
    873 		if (reply_type == RPCBPROC_INDIRECT)
    874 			svcerr_systemerr(transp);
    875 		AUTH_DESTROY(auth);
    876 		if (debugging)
    877 			fprintf(stderr,
    878 		"rpcbproc_callit_com:  AUTH_MARSHALL failed\n");
    879 		goto error;
    880 	}
    881 	AUTH_DESTROY(auth);
    882 	if (!xdr_opaque_parms(&outxdr, &a)) {
    883 		if (reply_type == RPCBPROC_INDIRECT)
    884 			svcerr_systemerr(transp);
    885 		if (debugging)
    886 			fprintf(stderr,
    887 		"rpcbproc_callit_com:  xdr_opaque_parms failed\n");
    888 		goto error;
    889 	}
    890 	outlen = (int) XDR_GETPOS(&outxdr);
    891 	if (outbuf_alloc)
    892 		outbufp = outbuf_alloc;
    893 	else
    894 		outbufp = outbuf;
    895 
    896 	na = uaddr2taddr(nconf, local_uaddr);
    897 	if (!na) {
    898 		if (reply_type == RPCBPROC_INDIRECT)
    899 			svcerr_systemerr(transp);
    900 		goto error;
    901 	}
    902 
    903 	if (sendto(fd, outbufp, outlen, 0, (struct sockaddr *)na->buf, na->len)
    904 	    != outlen) {
    905 		if (debugging)
    906 			fprintf(stderr,
    907 	"rpcbproc_callit_com:  sendto failed:  errno %d\n", errno);
    908 		if (reply_type == RPCBPROC_INDIRECT)
    909 			svcerr_systemerr(transp);
    910 		goto error;
    911 	}
    912 	goto out;
    913 
    914 error:
    915 	if (call_msg.rm_xid != 0)
    916 		(void) free_slot_by_xid(call_msg.rm_xid);
    917 out:
    918 	if (local_uaddr)
    919 		free(local_uaddr);
    920 	if (buf_alloc)
    921 		free(buf_alloc);
    922 	if (outbuf_alloc)
    923 		free(outbuf_alloc);
    924 	if (na) {
    925 		free(na->buf);
    926 		free(na);
    927 	}
    928 	if (m_uaddr != NULL)
    929 		free(m_uaddr);
    930 }
    931 
    932 /*
    933  * Makes an entry into the FIFO for the given request.
    934  * Returns 1 on success, 0 if this is a duplicate request, or -1 on error.
    935  * *callxidp is set to the xid of the call.
    936  */
    937 static int
    938 forward_register(u_int32_t caller_xid, struct netbuf *caller_addr,
    939     int forward_fd, char *uaddr, rpcproc_t reply_type,
    940      rpcvers_t versnum, u_int32_t *callxidp)
    941 {
    942 	int		i;
    943 	int		j = 0;
    944 	time_t		min_time, time_now;
    945 	static u_int32_t	lastxid;
    946 	int		entry = -1;
    947 
    948 	min_time = FINFO[0].time;
    949 	time_now = time((time_t *)0);
    950 	/* initialization */
    951 	if (lastxid == 0)
    952 		lastxid = time_now * NFORWARD;
    953 
    954 	/*
    955 	 * Check if it is a duplicate entry. Then,
    956 	 * try to find an empty slot.  If not available, then
    957 	 * use the slot with the earliest time.
    958 	 */
    959 	for (i = 0; i < NFORWARD; i++) {
    960 		if (FINFO[i].flag & FINFO_ACTIVE) {
    961 			if ((FINFO[i].caller_xid == caller_xid) &&
    962 			    (FINFO[i].reply_type == reply_type) &&
    963 			    (FINFO[i].versnum == versnum) &&
    964 			    (!netbufcmp(FINFO[i].caller_addr,
    965 					    caller_addr))) {
    966 				FINFO[i].time = time((time_t *)0);
    967 				return (0);	/* Duplicate entry */
    968 			} else {
    969 				/* Should we wait any longer */
    970 				if ((time_now - FINFO[i].time) > MAXTIME_OFF)
    971 					(void) free_slot_by_index(i);
    972 			}
    973 		}
    974 		if (entry == -1) {
    975 			if ((FINFO[i].flag & FINFO_ACTIVE) == 0) {
    976 				entry = i;
    977 			} else if (FINFO[i].time < min_time) {
    978 				j = i;
    979 				min_time = FINFO[i].time;
    980 			}
    981 		}
    982 	}
    983 	if (entry != -1) {
    984 		/* use this empty slot */
    985 		j = entry;
    986 	} else {
    987 		(void) free_slot_by_index(j);
    988 	}
    989 	if ((FINFO[j].caller_addr = netbufdup(caller_addr)) == NULL) {
    990 		return (-1);
    991 	}
    992 	rpcb_rmtcalls++;	/* no of pending calls */
    993 	FINFO[j].flag = FINFO_ACTIVE;
    994 	FINFO[j].reply_type = reply_type;
    995 	FINFO[j].versnum = versnum;
    996 	FINFO[j].time = time_now;
    997 	FINFO[j].caller_xid = caller_xid;
    998 	FINFO[j].forward_fd = forward_fd;
    999 	/*
   1000 	 * Though uaddr is not allocated here, it will still be freed
   1001 	 * from free_slot_*().
   1002 	 */
   1003 	FINFO[j].uaddr = uaddr;
   1004 	lastxid = lastxid + NFORWARD;
   1005 	/* Don't allow a zero xid below. */
   1006 	if ((u_int32_t)(lastxid + NFORWARD) <= NFORWARD)
   1007 		lastxid = NFORWARD;
   1008 	FINFO[j].forward_xid = lastxid + j;	/* encode slot */
   1009 	*callxidp = FINFO[j].forward_xid;	/* forward on this xid */
   1010 	return (1);
   1011 }
   1012 
   1013 static struct finfo *
   1014 forward_find(u_int32_t reply_xid)
   1015 {
   1016 	int		i;
   1017 
   1018 	i = reply_xid % NFORWARD;
   1019 	if (i < 0)
   1020 		i += NFORWARD;
   1021 	if ((FINFO[i].flag & FINFO_ACTIVE) &&
   1022 	    (FINFO[i].forward_xid == reply_xid)) {
   1023 		return (&FINFO[i]);
   1024 	}
   1025 	return (NULL);
   1026 }
   1027 
   1028 static int
   1029 free_slot_by_xid(u_int32_t xid)
   1030 {
   1031 	int entry;
   1032 
   1033 	entry = xid % NFORWARD;
   1034 	if (entry < 0)
   1035 		entry += NFORWARD;
   1036 	return (free_slot_by_index(entry));
   1037 }
   1038 
   1039 static int
   1040 free_slot_by_index(int idx)
   1041 {
   1042 	struct finfo	*fi;
   1043 
   1044 	fi = &FINFO[idx];
   1045 	if (fi->flag & FINFO_ACTIVE) {
   1046 		netbuffree(fi->caller_addr);
   1047 		/* XXX may be too big, but can't access xprt array here */
   1048 		if (fi->forward_fd >= *svc_fdset_getmax())
   1049 			(*svc_fdset_getmax())--;
   1050 		free(fi->uaddr);
   1051 		fi->flag &= ~FINFO_ACTIVE;
   1052 		rpcb_rmtcalls--;
   1053 		return (1);
   1054 	}
   1055 	return (0);
   1056 }
   1057 
   1058 static int
   1059 netbufcmp(struct netbuf *n1, struct netbuf *n2)
   1060 {
   1061 	return ((n1->len != n2->len) || memcmp(n1->buf, n2->buf, n1->len));
   1062 }
   1063 
   1064 static bool_t
   1065 netbuf_copybuf(struct netbuf *dst, const struct netbuf *src)
   1066 {
   1067 	assert(src->len <= src->maxlen);
   1068 
   1069 	if (dst->maxlen < src->len || dst->buf == NULL) {
   1070 		if (dst->buf != NULL)
   1071 			free(dst->buf);
   1072 		if ((dst->buf = calloc(1, src->maxlen)) == NULL)
   1073 			return (FALSE);
   1074 		dst->maxlen = src->maxlen;
   1075 	}
   1076 
   1077 	dst->len = src->len;
   1078 	memcpy(dst->buf, src->buf, src->len);
   1079 
   1080 	return (TRUE);
   1081 }
   1082 
   1083 static struct netbuf *
   1084 netbufdup(struct netbuf *ap)
   1085 {
   1086 	struct netbuf  *np;
   1087 
   1088 	if ((np = calloc(1, sizeof(struct netbuf))) == NULL)
   1089 		return (NULL);
   1090 	if (netbuf_copybuf(np, ap) == FALSE) {
   1091 		free(np);
   1092 		return (NULL);
   1093 	}
   1094 	return (np);
   1095 }
   1096 
   1097 static void
   1098 netbuffree(struct netbuf *ap)
   1099 {
   1100 	free(ap->buf);
   1101 	ap->buf = NULL;
   1102 	free(ap);
   1103 }
   1104 
   1105 
   1106 #define	MASKVAL	(POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)
   1107 extern bool_t __svc_clean_idle(fd_set *, int, bool_t);
   1108 
   1109 void
   1110 my_svc_run(void)
   1111 {
   1112 	size_t nfds;
   1113 	struct pollfd *pollfds;
   1114 	int npollfds;
   1115 	int poll_ret, check_ret;
   1116 	int n, *m;
   1117 #ifdef SVC_RUN_DEBUG
   1118 	int i;
   1119 #endif
   1120 	struct pollfd	*p;
   1121 
   1122 	pollfds = NULL;
   1123 	npollfds = 0;
   1124 
   1125 	for (;;) {
   1126 		if (svc_fdset_getsize(0) != npollfds) {
   1127 			npollfds = svc_fdset_getsize(0);
   1128 			pollfds = realloc(pollfds, npollfds * sizeof(*pollfds));
   1129 		}
   1130 		p = pollfds;
   1131 		if (p == NULL) {
   1132 out:
   1133 			syslog(LOG_ERR, "Cannot allocate pollfds");
   1134 			sleep(1);
   1135 			continue;
   1136 		}
   1137 		if ((m = svc_fdset_getmax()) == NULL)
   1138 			goto out;
   1139 		for (n = 0; n <= *m; n++) {
   1140 			if (svc_fdset_isset(n)) {
   1141 				p->fd = n;
   1142 				p->events = MASKVAL;
   1143 				p++;
   1144 			}
   1145 		}
   1146 		nfds = p - pollfds;
   1147 		poll_ret = 0;
   1148 #ifdef SVC_RUN_DEBUG
   1149 		if (debugging) {
   1150 			fprintf(stderr, "polling for read on fd < ");
   1151 			for (i = 0, p = pollfds; i < nfds; i++, p++)
   1152 				if (p->events)
   1153 					fprintf(stderr, "%d ", p->fd);
   1154 			fprintf(stderr, ">\n");
   1155 		}
   1156 #endif
   1157 #ifdef RPCBIND_RUMP
   1158 		poll_ret = rump_sys_poll(pollfds, nfds, 30 * 1000);
   1159 #else
   1160 		poll_ret = poll(pollfds, nfds, 30 * 1000);
   1161 #endif
   1162 		switch (poll_ret) {
   1163 		case -1:
   1164 			/*
   1165 			 * We ignore all errors, continuing with the assumption
   1166 			 * that it was set by the signal handlers (or any
   1167 			 * other outside event) and not caused by poll().
   1168 			 */
   1169 #ifdef SVC_RUN_DEBUG
   1170 			if (debugging) {
   1171 				fprintf(stderr, "poll returned %d (%s)\n",
   1172 				    poll_ret, strerror(errno));
   1173 			}
   1174 #endif
   1175 		case 0:
   1176 			__svc_clean_idle(NULL, 30, FALSE);
   1177 			continue;
   1178 		default:
   1179 #ifdef SVC_RUN_DEBUG
   1180 			if (debugging) {
   1181 				fprintf(stderr, "poll returned read fds < ");
   1182 				for (i = 0, p = pollfds; i < nfds; i++, p++)
   1183 					if (p->revents)
   1184 						fprintf(stderr, "%d (%#x)",
   1185 						    p->fd, p->revents);
   1186 				fprintf(stderr, ">\n");
   1187 			}
   1188 #endif
   1189 			/*
   1190 			 * If we found as many replies on callback fds
   1191 			 * as the number of descriptors selectable which
   1192 			 * poll() returned, there can be no more so we
   1193 			 * don't call svc_getreq_poll.  Otherwise, there
   1194 			 * must be another so we must call svc_getreq_poll.
   1195 			 */
   1196 			if ((check_ret = check_rmtcalls(pollfds, nfds)) ==
   1197 			    poll_ret)
   1198 				continue;
   1199 			svc_getreq_poll(pollfds, poll_ret-check_ret);
   1200 		}
   1201 #ifdef SVC_RUN_DEBUG
   1202 		if (debugging) {
   1203 			fprintf(stderr, "svc_maxfd now %u\n",
   1204 			    *svc_fdset_getmax());
   1205 		}
   1206 #endif
   1207 	}
   1208 }
   1209 
   1210 static int
   1211 check_rmtcalls(struct pollfd *pfds, int nfds)
   1212 {
   1213 	int j, ncallbacks_found = 0, rmtcalls_pending;
   1214 	SVCXPRT *xprt;
   1215 
   1216 	if (rpcb_rmtcalls == 0)
   1217 		return (0);
   1218 
   1219 	rmtcalls_pending = rpcb_rmtcalls;
   1220 	for (j = 0; j < nfds; j++) {
   1221 		if ((xprt = find_rmtcallxprt_by_fd(pfds[j].fd)) != NULL) {
   1222 			if (pfds[j].revents) {
   1223 				ncallbacks_found++;
   1224 #ifdef DEBUG_RMTCALL
   1225 			if (debugging)
   1226 				fprintf(stderr,
   1227 "my_svc_run:  polled on forwarding fd %d, netid %s - calling handle_reply\n",
   1228 		pfds[j].fd, xprt->xp_netid);
   1229 #endif
   1230 				handle_reply(pfds[j].fd, xprt);
   1231 				pfds[j].revents = 0;
   1232 				if (ncallbacks_found >= rmtcalls_pending) {
   1233 					break;
   1234 				}
   1235 			}
   1236 		}
   1237 	}
   1238 	return (ncallbacks_found);
   1239 }
   1240 
   1241 static void
   1242 xprt_set_caller(SVCXPRT *xprt, struct finfo *fi)
   1243 {
   1244 	u_int32_t *xidp;
   1245 
   1246 	netbuf_copybuf(svc_getrpccaller(xprt), fi->caller_addr);
   1247 	xidp = __rpcb_get_dg_xidp(xprt);
   1248 	*xidp = fi->caller_xid;
   1249 }
   1250 
   1251 /*
   1252  * Call svcerr_systemerr() only if RPCBVERS4
   1253  */
   1254 static void
   1255 send_svcsyserr(SVCXPRT *xprt, struct finfo *fi)
   1256 {
   1257 	if (fi->reply_type == RPCBPROC_INDIRECT) {
   1258 		xprt_set_caller(xprt, fi);
   1259 		svcerr_systemerr(xprt);
   1260 	}
   1261 	return;
   1262 }
   1263 
   1264 static void
   1265 handle_reply(int fd, SVCXPRT *xprt)
   1266 {
   1267 	XDR		reply_xdrs;
   1268 	struct rpc_msg	reply_msg;
   1269 	struct rpc_err	reply_error;
   1270 	char		*buffer;
   1271 	struct finfo	*fi;
   1272 	int		inlen, pos, len;
   1273 	struct r_rmtcall_args a;
   1274 	struct sockaddr_storage ss;
   1275 	socklen_t fromlen;
   1276 #ifdef SVC_RUN_DEBUG
   1277 	char *uaddr;
   1278 #endif
   1279 
   1280 	buffer = malloc(RPC_BUF_MAX);
   1281 	if (buffer == NULL)
   1282 		goto done;
   1283 
   1284 	do {
   1285 		fromlen = sizeof(ss);
   1286 		inlen = recvfrom(fd, buffer, RPC_BUF_MAX, 0,
   1287 			    (struct sockaddr *)&ss, &fromlen);
   1288 	} while (inlen < 0 && errno == EINTR);
   1289 	if (inlen < 0) {
   1290 		if (debugging)
   1291 			fprintf(stderr,
   1292 	"handle_reply:  recvfrom returned %d, errno %d\n", inlen, errno);
   1293 		goto done;
   1294 	}
   1295 
   1296 	reply_msg.acpted_rply.ar_verf = _null_auth;
   1297 	reply_msg.acpted_rply.ar_results.where = 0;
   1298 	reply_msg.acpted_rply.ar_results.proc = (xdrproc_t) xdr_void;
   1299 
   1300 	xdrmem_create(&reply_xdrs, buffer, (u_int)inlen, XDR_DECODE);
   1301 	if (!xdr_replymsg(&reply_xdrs, &reply_msg)) {
   1302 		if (debugging)
   1303 			(void) fprintf(stderr,
   1304 				"handle_reply:  xdr_replymsg failed\n");
   1305 		goto done;
   1306 	}
   1307 	fi = forward_find(reply_msg.rm_xid);
   1308 #ifdef	SVC_RUN_DEBUG
   1309 	if (debugging) {
   1310 		fprintf(stderr, "handle_reply:  reply xid: %d fi addr: %p\n",
   1311 			reply_msg.rm_xid, fi);
   1312 	}
   1313 #endif
   1314 	if (fi == NULL) {
   1315 		goto done;
   1316 	}
   1317 	_seterr_reply(&reply_msg, &reply_error);
   1318 	if (reply_error.re_status != RPC_SUCCESS) {
   1319 		if (debugging)
   1320 			(void) fprintf(stderr, "handle_reply:  %s\n",
   1321 				clnt_sperrno(reply_error.re_status));
   1322 		send_svcsyserr(xprt, fi);
   1323 		goto done;
   1324 	}
   1325 	pos = XDR_GETPOS(&reply_xdrs);
   1326 	len = inlen - pos;
   1327 	a.rmt_args.args = &buffer[pos];
   1328 	a.rmt_args.arglen = len;
   1329 	a.rmt_uaddr = fi->uaddr;
   1330 	a.rmt_localvers = fi->versnum;
   1331 
   1332 	xprt_set_caller(xprt, fi);
   1333 #ifdef	SVC_RUN_DEBUG
   1334 	uaddr =	taddr2uaddr(rpcbind_get_conf("udp"),
   1335 				    svc_getrpccaller(xprt));
   1336 	if (debugging) {
   1337 		fprintf(stderr, "handle_reply:  forwarding address %s to %s\n",
   1338 			a.rmt_uaddr, uaddr ? uaddr : rpcbind_unknown);
   1339 	}
   1340 	if (uaddr)
   1341 		free(uaddr);
   1342 #endif
   1343 	svc_sendreply(xprt, (xdrproc_t) xdr_rmtcall_result, (char *) &a);
   1344 done:
   1345 	if (buffer)
   1346 		free(buffer);
   1347 
   1348 	if (reply_msg.rm_xid == 0) {
   1349 #ifdef	SVC_RUN_DEBUG
   1350 	if (debugging) {
   1351 		fprintf(stderr, "handle_reply:  NULL xid on exit!\n");
   1352 	}
   1353 #endif
   1354 	} else
   1355 		(void) free_slot_by_xid(reply_msg.rm_xid);
   1356 	return;
   1357 }
   1358 
   1359 static void
   1360 find_versions(rpcprog_t prog, char *netid, rpcvers_t *lowvp, rpcvers_t *highvp)
   1361 {
   1362 	rpcblist_ptr rbl;
   1363 	rpcvers_t lowv = 0;
   1364 	rpcvers_t highv = 0;
   1365 
   1366 	for (rbl = list_rbl; rbl != NULL; rbl = rbl->rpcb_next) {
   1367 		if ((rbl->rpcb_map.r_prog != prog) ||
   1368 		    ((rbl->rpcb_map.r_netid != NULL) &&
   1369 			(strcasecmp(rbl->rpcb_map.r_netid, netid) != 0)))
   1370 			continue;
   1371 		if (lowv == 0) {
   1372 			highv = rbl->rpcb_map.r_vers;
   1373 			lowv = highv;
   1374 		} else if (rbl->rpcb_map.r_vers < lowv) {
   1375 			lowv = rbl->rpcb_map.r_vers;
   1376 		} else if (rbl->rpcb_map.r_vers > highv) {
   1377 			highv = rbl->rpcb_map.r_vers;
   1378 		}
   1379 	}
   1380 	*lowvp = lowv;
   1381 	*highvp = highv;
   1382 	return;
   1383 }
   1384 
   1385 /*
   1386  * returns the item with the given program, version number and netid.
   1387  * If that version number is not found, it returns the item with that
   1388  * program number, so that address is now returned to the caller. The
   1389  * caller when makes a call to this program, version number, the call
   1390  * will fail and it will return with PROGVERS_MISMATCH. The user can
   1391  * then determine the highest and the lowest version number for this
   1392  * program using clnt_geterr() and use those program version numbers.
   1393  *
   1394  * Returns the RPCBLIST for the given prog, vers and netid
   1395  */
   1396 static rpcblist_ptr
   1397 find_service(rpcprog_t prog, rpcvers_t vers, char *netid)
   1398 {
   1399 	rpcblist_ptr hit = NULL;
   1400 	rpcblist_ptr rbl;
   1401 
   1402 	for (rbl = list_rbl; rbl != NULL; rbl = rbl->rpcb_next) {
   1403 		if ((rbl->rpcb_map.r_prog != prog) ||
   1404 		    ((rbl->rpcb_map.r_netid != NULL) &&
   1405 			(strcasecmp(rbl->rpcb_map.r_netid, netid) != 0)))
   1406 			continue;
   1407 		hit = rbl;
   1408 		if (rbl->rpcb_map.r_vers == vers)
   1409 			break;
   1410 	}
   1411 	return (hit);
   1412 }
   1413 
   1414 /*
   1415  * Copies the name associated with the uid of the caller and returns
   1416  * a pointer to it.  Similar to getwd().
   1417  */
   1418 static char *
   1419 getowner(SVCXPRT *transp, char *owner, size_t ownersize)
   1420 {
   1421 	struct sockcred *sc;
   1422 
   1423 	sc = __svc_getcallercreds(transp);
   1424 	if (sc == NULL)
   1425 		strlcpy(owner, rpcbind_unknown, ownersize);
   1426 	else if (sc->sc_uid == 0)
   1427 		strlcpy(owner, rpcbind_superuser, ownersize);
   1428 	else
   1429 		snprintf(owner, ownersize, "%d", sc->sc_uid);
   1430 
   1431 	return owner;
   1432 }
   1433 
   1434 #ifdef PORTMAP
   1435 /*
   1436  * Add this to the pmap list only if it is UDP or TCP.
   1437  */
   1438 static int
   1439 add_pmaplist(RPCB *arg)
   1440 {
   1441 	struct pmap pmap;
   1442 	struct pmaplist *pml;
   1443 	int h1, h2, h3, h4, p1, p2;
   1444 
   1445 	if (strcmp(arg->r_netid, udptrans) == 0) {
   1446 		/* It is UDP! */
   1447 		pmap.pm_prot = IPPROTO_UDP;
   1448 	} else if (strcmp(arg->r_netid, tcptrans) == 0) {
   1449 		/* It is TCP */
   1450 		pmap.pm_prot = IPPROTO_TCP;
   1451 	} else
   1452 		/* Not an IP protocol */
   1453 		return (0);
   1454 
   1455 	/* interpret the universal address for TCP/IP */
   1456 	if (sscanf(arg->r_addr, "%d.%d.%d.%d.%d.%d",
   1457 		&h1, &h2, &h3, &h4, &p1, &p2) != 6)
   1458 		return (0);
   1459 	pmap.pm_port = ((p1 & 0xff) << 8) + (p2 & 0xff);
   1460 	pmap.pm_prog = arg->r_prog;
   1461 	pmap.pm_vers = arg->r_vers;
   1462 	/*
   1463 	 * add to END of list
   1464 	 */
   1465 	pml = malloc(sizeof(*pml));
   1466 	if (pml == NULL) {
   1467 		syslog(LOG_ERR, "%s: Cannot allocate memory", __func__);
   1468 		return (1);
   1469 	}
   1470 	pml->pml_map = pmap;
   1471 	pml->pml_next = NULL;
   1472 	if (list_pml == NULL) {
   1473 		list_pml = pml;
   1474 	} else {
   1475 		struct pmaplist *fnd;
   1476 
   1477 		/* Attach to the end of the list */
   1478 		for (fnd = list_pml; fnd->pml_next; fnd = fnd->pml_next)
   1479 			continue;
   1480 		fnd->pml_next = pml;
   1481 	}
   1482 	return (0);
   1483 }
   1484 
   1485 /*
   1486  * Delete this from the pmap list only if it is UDP or TCP.
   1487  */
   1488 static int
   1489 del_pmaplist(RPCB *arg)
   1490 {
   1491 	struct pmaplist *pml;
   1492 	struct pmaplist *prevpml, *fnd;
   1493 	unsigned long prot;
   1494 
   1495 	if (strcmp(arg->r_netid, udptrans) == 0) {
   1496 		/* It is UDP! */
   1497 		prot = IPPROTO_UDP;
   1498 	} else if (strcmp(arg->r_netid, tcptrans) == 0) {
   1499 		/* It is TCP */
   1500 		prot = IPPROTO_TCP;
   1501 	} else if (arg->r_netid[0] == 0) {
   1502 		prot = 0;	/* Remove all occurrences */
   1503 	} else {
   1504 		/* Not an IP protocol */
   1505 		return (0);
   1506 	}
   1507 	for (prevpml = NULL, pml = list_pml; pml; /* cstyle */) {
   1508 		if ((pml->pml_map.pm_prog != arg->r_prog) ||
   1509 			(pml->pml_map.pm_vers != arg->r_vers) ||
   1510 			(prot && (pml->pml_map.pm_prot != prot))) {
   1511 			/* both pml & prevpml move forwards */
   1512 			prevpml = pml;
   1513 			pml = pml->pml_next;
   1514 			continue;
   1515 		}
   1516 		/* found it; pml moves forward, prevpml stays */
   1517 		fnd = pml;
   1518 		pml = pml->pml_next;
   1519 		if (prevpml == NULL)
   1520 			list_pml = pml;
   1521 		else
   1522 			prevpml->pml_next = pml;
   1523 		free(fnd);
   1524 	}
   1525 	return (0);
   1526 }
   1527 #endif /* PORTMAP */
   1528