freebsd-skq/usr.sbin/ypldap/yp.c
Konstantin Belousov 6b462d2762 Increase YPMAXRECORD to 16M to be compatible with Linux.
Since YP protocol definition uses the constant to declare
variable-size opaque byte strings, the change should be binary
compatible with existing installations which do not expose keys or
values larger than 1024 bytes.

All uses of local variables with YPMAXRECORD sizes were removed to
avoid insane stack use.  On the other hand, variables with static
lifetime should be fine and only result in increased VA use.

Glibc made same change, increasing the allowed length for keys and
values in YP to 16M, in 2013.

Reviewed by:	markj
Discussed with:	ian
Sponsored by:	Mellanox Technologies
MFC after:	3 weeks
Differential revision:	https://reviews.freebsd.org/D20900
2019-08-12 20:27:33 +00:00

681 lines
16 KiB
C

/* $OpenBSD: yp.c,v 1.14 2015/02/11 01:26:00 pelikan Exp $ */
/* $FreeBSD$ */
/*
* Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <sys/tree.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <event.h>
#include <fcntl.h>
#include <unistd.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <rpc/rpc.h>
#include <rpc/xdr.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_rmt.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>
#include "ypldap.h"
void yp_dispatch(struct svc_req *, SVCXPRT *);
void yp_disable_events(void);
void yp_fd_event(int, short, void *);
int yp_check(struct svc_req *);
int yp_valid_domain(char *, struct ypresp_val *);
void yp_make_val(struct ypresp_val *, char *, int);
void yp_make_keyval(struct ypresp_key_val *, char *, char *);
static struct env *env;
struct yp_event {
TAILQ_ENTRY(yp_event) ye_entry;
struct event ye_event;
};
struct yp_data {
SVCXPRT *yp_trans_udp;
SVCXPRT *yp_trans_tcp;
TAILQ_HEAD(, yp_event) yd_events;
};
void
yp_disable_events(void)
{
struct yp_event *ye;
while ((ye = TAILQ_FIRST(&env->sc_yp->yd_events)) != NULL) {
TAILQ_REMOVE(&env->sc_yp->yd_events, ye, ye_entry);
event_del(&ye->ye_event);
free(ye);
}
}
void
yp_enable_events(void)
{
int i;
struct yp_event *ye;
for (i = 0; i < getdtablesize(); i++) {
if ((ye = calloc(1, sizeof(*ye))) == NULL)
fatal(NULL);
event_set(&ye->ye_event, i, EV_READ, yp_fd_event, NULL);
event_add(&ye->ye_event, NULL);
TAILQ_INSERT_TAIL(&env->sc_yp->yd_events, ye, ye_entry);
}
}
void
yp_fd_event(int fd, short event, void *p)
{
svc_getreq_common(fd);
yp_disable_events();
yp_enable_events();
}
void
yp_init(struct env *x_env)
{
struct yp_data *yp;
if ((yp = calloc(1, sizeof(*yp))) == NULL)
fatal(NULL);
TAILQ_INIT(&yp->yd_events);
env = x_env;
env->sc_yp = yp;
(void)pmap_unset(YPPROG, YPVERS);
if ((yp->yp_trans_udp = svcudp_create(RPC_ANYSOCK)) == NULL)
fatal("cannot create udp service");
if ((yp->yp_trans_tcp = svctcp_create(RPC_ANYSOCK, 0, 0)) == NULL)
fatal("cannot create tcp service");
if (!svc_register(yp->yp_trans_udp, YPPROG, YPVERS,
yp_dispatch, IPPROTO_UDP)) {
fatal("unable to register (YPPROG, YPVERS, udp)");
}
if (!svc_register(yp->yp_trans_tcp, YPPROG, YPVERS,
yp_dispatch, IPPROTO_TCP)) {
fatal("unable to register (YPPROG, YPVERS, tcp)");
}
}
/*
* lots of inspiration from ypserv by Mats O Jansson
*/
void
yp_dispatch(struct svc_req *req, SVCXPRT *trans)
{
xdrproc_t xdr_argument;
xdrproc_t xdr_result;
char *result;
char *(*cb)(char *, struct svc_req *);
union {
domainname ypproc_domain_2_arg;
domainname ypproc_domain_nonack_2_arg;
ypreq_key ypproc_match_2_arg;
ypreq_nokey ypproc_first_2_arg;
ypreq_key ypproc_next_2_arg;
ypreq_xfr ypproc_xfr_2_arg;
ypreq_nokey ypproc_all_2_arg;
ypreq_nokey ypproc_master_2_arg;
ypreq_nokey ypproc_order_2_arg;
domainname ypproc_maplist_2_arg;
} argument;
xdr_argument = (xdrproc_t) xdr_void;
xdr_result = (xdrproc_t) xdr_void;
cb = NULL;
switch (req->rq_proc) {
case YPPROC_NULL:
xdr_argument = (xdrproc_t) xdr_void;
xdr_result = (xdrproc_t) xdr_void;
if (yp_check(req) == -1)
return;
result = NULL;
if (!svc_sendreply(trans, (xdrproc_t) xdr_void,
(void *)&result))
svcerr_systemerr(trans);
return;
case YPPROC_DOMAIN:
xdr_argument = (xdrproc_t) xdr_domainname;
xdr_result = (xdrproc_t) xdr_bool;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_domain_2_svc;
break;
case YPPROC_DOMAIN_NONACK:
xdr_argument = (xdrproc_t) xdr_domainname;
xdr_result = (xdrproc_t) xdr_bool;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_domain_nonack_2_svc;
break;
case YPPROC_MATCH:
xdr_argument = (xdrproc_t) xdr_ypreq_key;
xdr_result = (xdrproc_t) xdr_ypresp_val;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_match_2_svc;
break;
case YPPROC_FIRST:
xdr_argument = (xdrproc_t) xdr_ypreq_nokey;
xdr_result = (xdrproc_t) xdr_ypresp_key_val;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_first_2_svc;
break;
case YPPROC_NEXT:
xdr_argument = (xdrproc_t) xdr_ypreq_key;
xdr_result = (xdrproc_t) xdr_ypresp_key_val;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_next_2_svc;
break;
case YPPROC_XFR:
if (yp_check(req) == -1)
return;
svcerr_noproc(trans);
return;
case YPPROC_CLEAR:
log_debug("ypproc_clear");
if (yp_check(req) == -1)
return;
svcerr_noproc(trans);
return;
case YPPROC_ALL:
log_debug("ypproc_all");
xdr_argument = (xdrproc_t) xdr_ypreq_nokey;
xdr_result = (xdrproc_t) xdr_ypresp_all;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_all_2_svc;
break;
case YPPROC_MASTER:
log_debug("ypproc_master");
xdr_argument = (xdrproc_t) xdr_ypreq_nokey;
xdr_result = (xdrproc_t) xdr_ypresp_master;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_master_2_svc;
break;
case YPPROC_ORDER:
log_debug("ypproc_order");
if (yp_check(req) == -1)
return;
svcerr_noproc(trans);
return;
case YPPROC_MAPLIST:
log_debug("ypproc_maplist");
xdr_argument = (xdrproc_t) xdr_domainname;
xdr_result = (xdrproc_t) xdr_ypresp_maplist;
if (yp_check(req) == -1)
return;
cb = (void *)ypproc_maplist_2_svc;
break;
default:
svcerr_noproc(trans);
return;
}
(void)memset(&argument, 0, sizeof(argument));
if (!svc_getargs(trans, xdr_argument, (caddr_t)&argument)) {
svcerr_decode(trans);
return;
}
result = (*cb)((char *)&argument, req);
if (result != NULL && !svc_sendreply(trans, xdr_result, result))
svcerr_systemerr(trans);
if (!svc_freeargs(trans, xdr_argument, (caddr_t)&argument)) {
/*
* ypserv does it too.
*/
fatal("unable to free arguments");
}
}
int
yp_check(struct svc_req *req)
{
struct sockaddr_in *caller;
caller = svc_getcaller(req->rq_xprt);
/*
* We might want to know who we allow here.
*/
return (0);
}
int
yp_valid_domain(char *domain, struct ypresp_val *res)
{
if (domain == NULL) {
log_debug("NULL domain !");
return (-1);
}
if (strcmp(domain, env->sc_domainname) != 0) {
res->stat = YP_NODOM;
return (-1);
}
return (0);
}
bool_t *
ypproc_domain_2_svc(domainname *arg, struct svc_req *req)
{
static bool_t res;
res = (bool_t)1;
if (strcmp(*arg, env->sc_domainname) != 0)
res = (bool_t)0;
return (&res);
}
bool_t *
ypproc_domain_nonack_2_svc(domainname *arg, struct svc_req *req)
{
static bool_t res;
if (strcmp(*arg, env->sc_domainname) != 0)
return NULL;
res = (bool_t)1;
return (&res);
}
ypresp_val *
ypproc_match_2_svc(ypreq_key *arg, struct svc_req *req)
{
struct userent ukey;
struct userent *ue;
struct groupent gkey;
struct groupent *ge;
static struct ypresp_val res;
const char *estr;
char *bp, *cp;
char *key;
log_debug("matching '%.*s' in map %s", arg->key.keydat_len,
arg->key.keydat_val, arg->map);
if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
return (&res);
if (env->sc_user_names == NULL) {
/*
* tree not ready.
*/
return (NULL);
}
if (arg->key.keydat_len > YPMAXRECORD) {
log_debug("argument too long");
return (NULL);
}
key = calloc(arg->key.keydat_len + 1, 1);
if (key == NULL)
return (NULL);
(void)strncpy(key, arg->key.keydat_val, arg->key.keydat_len);
if (strcmp(arg->map, "passwd.byname") == 0 ||
strcmp(arg->map, "master.passwd.byname") == 0) {
ukey.ue_line = key;
if ((ue = RB_FIND(user_name_tree, env->sc_user_names,
&ukey)) == NULL) {
res.stat = YP_NOKEY;
goto out;
}
yp_make_val(&res, ue->ue_line, 1);
goto out;
} else if (strcmp(arg->map, "passwd.byuid") == 0 ||
strcmp(arg->map, "master.passwd.byuid") == 0) {
ukey.ue_uid = strtonum(key, 0, UID_MAX, &estr);
if (estr) {
res.stat = YP_BADARGS;
goto out;
}
if ((ue = RB_FIND(user_uid_tree, &env->sc_user_uids,
&ukey)) == NULL) {
res.stat = YP_NOKEY;
goto out;
}
yp_make_val(&res, ue->ue_line, 1);
return (&res);
} else if (strcmp(arg->map, "group.bygid") == 0) {
gkey.ge_gid = strtonum(key, 0, GID_MAX, &estr);
if (estr) {
res.stat = YP_BADARGS;
goto out;
}
if ((ge = RB_FIND(group_gid_tree, &env->sc_group_gids,
&gkey)) == NULL) {
res.stat = YP_NOKEY;
goto out;
}
yp_make_val(&res, ge->ge_line, 1);
return (&res);
} else if (strcmp(arg->map, "group.byname") == 0) {
gkey.ge_line = key;
if ((ge = RB_FIND(group_name_tree, env->sc_group_names,
&gkey)) == NULL) {
res.stat = YP_NOKEY;
goto out;
}
yp_make_val(&res, ge->ge_line, 1);
return (&res);
} else if (strcmp(arg->map, "netid.byname") == 0) {
bp = cp = key;
if (strncmp(bp, "unix.", strlen("unix.")) != 0) {
res.stat = YP_BADARGS;
goto out;
}
bp += strlen("unix.");
if (*bp == '\0') {
res.stat = YP_BADARGS;
goto out;
}
if (!(cp = strsep(&bp, "@"))) {
res.stat = YP_BADARGS;
goto out;
}
if (strcmp(bp, arg->domain) != 0) {
res.stat = YP_BADARGS;
goto out;
}
ukey.ue_uid = strtonum(cp, 0, UID_MAX, &estr);
if (estr) {
res.stat = YP_BADARGS;
goto out;
}
if ((ue = RB_FIND(user_uid_tree, &env->sc_user_uids,
&ukey)) == NULL) {
res.stat = YP_NOKEY;
goto out;
}
yp_make_val(&res, ue->ue_netid_line, 0);
goto out;
} else {
log_debug("unknown map %s", arg->map);
res.stat = YP_NOMAP;
goto out;
}
out:
free(key);
return (&res);
}
ypresp_key_val *
ypproc_first_2_svc(ypreq_nokey *arg, struct svc_req *req)
{
static struct ypresp_key_val res;
if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
return (&res);
if (strcmp(arg->map, "passwd.byname") == 0 ||
strcmp(arg->map, "master.passwd.byname") == 0) {
if (env->sc_user_lines == NULL)
return (NULL);
yp_make_keyval(&res, env->sc_user_lines, env->sc_user_lines);
} else if (strcmp(arg->map, "group.byname") == 0) {
if (env->sc_group_lines == NULL)
return (NULL);
yp_make_keyval(&res, env->sc_group_lines, env->sc_group_lines);
} else {
log_debug("unknown map %s", arg->map);
res.stat = YP_NOMAP;
}
return (&res);
}
ypresp_key_val *
ypproc_next_2_svc(ypreq_key *arg, struct svc_req *req)
{
struct userent ukey;
struct userent *ue;
struct groupent gkey;
struct groupent *ge;
char *line;
static struct ypresp_key_val res;
char *key;
if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
return (&res);
key = NULL;
if (strcmp(arg->map, "passwd.byname") == 0 ||
strcmp(arg->map, "master.passwd.byname") == 0) {
key = calloc(arg->key.keydat_len + 1, 1);
if (key == NULL) {
res.stat = YP_YPERR;
return (&res);
}
(void)strncpy(key, arg->key.keydat_val,
arg->key.keydat_len);
ukey.ue_line = key;
if ((ue = RB_FIND(user_name_tree, env->sc_user_names,
&ukey)) == NULL) {
/*
* canacar's trick:
* the user might have been deleted in between calls
* to next since the tree may be modified by a reload.
* next should still return the next user in
* lexicographical order, hence insert the search key
* and look up the next field, then remove it again.
*/
RB_INSERT(user_name_tree, env->sc_user_names, &ukey);
if ((ue = RB_NEXT(user_name_tree, &env->sc_user_names,
&ukey)) == NULL) {
RB_REMOVE(user_name_tree, env->sc_user_names,
&ukey);
res.stat = YP_NOKEY;
free(key);
return (&res);
}
RB_REMOVE(user_name_tree, env->sc_user_names, &ukey);
}
line = ue->ue_line + (strlen(ue->ue_line) + 1);
line = line + (strlen(line) + 1);
yp_make_keyval(&res, line, line);
free(key);
return (&res);
} else if (strcmp(arg->map, "group.byname") == 0) {
key = calloc(arg->key.keydat_len + 1, 1);
if (key == NULL) {
res.stat = YP_YPERR;
return (&res);
}
(void)strncpy(key, arg->key.keydat_val,
arg->key.keydat_len);
gkey.ge_line = key;
if ((ge = RB_FIND(group_name_tree, env->sc_group_names,
&gkey)) == NULL) {
/*
* canacar's trick reloaded.
*/
RB_INSERT(group_name_tree, env->sc_group_names, &gkey);
if ((ge = RB_NEXT(group_name_tree, &env->sc_group_names,
&gkey)) == NULL) {
RB_REMOVE(group_name_tree, env->sc_group_names,
&gkey);
res.stat = YP_NOKEY;
free(key);
return (&res);
}
RB_REMOVE(group_name_tree, env->sc_group_names, &gkey);
}
line = ge->ge_line + (strlen(ge->ge_line) + 1);
line = line + (strlen(line) + 1);
yp_make_keyval(&res, line, line);
free(key);
return (&res);
} else {
log_debug("unknown map %s", arg->map);
res.stat = YP_NOMAP;
return (&res);
}
}
ypresp_all *
ypproc_all_2_svc(ypreq_nokey *arg, struct svc_req *req)
{
static struct ypresp_all res;
if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
return (&res);
svcerr_auth(req->rq_xprt, AUTH_FAILED);
return (NULL);
}
ypresp_master *
ypproc_master_2_svc(ypreq_nokey *arg, struct svc_req *req)
{
static struct ypresp_master res;
static char master[YPMAXPEER + 1];
memset(&res, 0, sizeof(res));
if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
return (&res);
if (gethostname(master, sizeof(master)) == 0) {
res.peer = (peername)master;
res.stat = YP_TRUE;
} else
res.stat = YP_NOKEY;
return (&res);
}
ypresp_maplist *
ypproc_maplist_2_svc(domainname *arg, struct svc_req *req)
{
size_t i;
static struct {
char *name;
int cond;
} mapnames[] = {
{ "passwd.byname", YPMAP_PASSWD_BYNAME },
{ "passwd.byuid", YPMAP_PASSWD_BYUID },
{ "master.passwd.byname", YPMAP_MASTER_PASSWD_BYNAME },
{ "master.passwd.byuid", YPMAP_MASTER_PASSWD_BYUID },
{ "group.byname", YPMAP_GROUP_BYNAME },
{ "group.bygid", YPMAP_GROUP_BYGID },
{ "netid.byname", YPMAP_NETID_BYNAME },
};
static ypresp_maplist res;
static struct ypmaplist maps[nitems(mapnames)];
if (yp_valid_domain(*arg, (struct ypresp_val *)&res) == -1)
return (&res);
res.stat = YP_TRUE;
res.maps = NULL;
for (i = 0; i < nitems(mapnames); i++) {
if (!(env->sc_flags & mapnames[i].cond))
continue;
maps[i].map = mapnames[i].name;
maps[i].next = res.maps;
res.maps = &maps[i];
}
return (&res);
}
void
yp_make_val(struct ypresp_val *res, char *line, int replacecolon)
{
static char buf[LINE_WIDTH];
memset(buf, 0, sizeof(buf));
if (replacecolon)
line[strlen(line)] = ':';
(void)strlcpy(buf, line, sizeof(buf));
if (replacecolon)
line[strcspn(line, ":")] = '\0';
log_debug("sending out %s", buf);
res->stat = YP_TRUE;
res->val.valdat_len = strlen(buf);
res->val.valdat_val = buf;
}
void
yp_make_keyval(struct ypresp_key_val *res, char *key, char *line)
{
static char keybuf[YPMAXRECORD+1];
static char buf[LINE_WIDTH];
memset(keybuf, 0, sizeof(keybuf));
memset(buf, 0, sizeof(buf));
(void)strlcpy(keybuf, key, sizeof(keybuf));
res->key.keydat_len = strlen(keybuf);
res->key.keydat_val = keybuf;
if (*line == '\0') {
res->stat = YP_NOMORE;
return;
}
res->stat = YP_TRUE;
line[strlen(line)] = ':';
(void)strlcpy(buf, line, sizeof(buf));
line[strcspn(line, ":")] = '\0';
log_debug("sending out %s => %s", keybuf, buf);
res->val.valdat_len = strlen(buf);
res->val.valdat_val = buf;
}