/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include "lint.h"

#include "file64.h"

#include "mtlib.h"

#include "libc.h"

#include <synch.h>

#include <sys/types.h>

#include <stdlib.h>

#include <stdio.h>

#include <stdio_ext.h>

#include <string.h>

#include <ctype.h>

#include <limits.h>

#include <dlfcn.h>

#include <errno.h>

#include "stdiom.h"

#define	__NSS_PRIVATE_INTERFACE

#include "nsswitch_priv.h"

#undef	__NSS_PRIVATE_INTERFACE

#include <syslog.h>

#define	islabel(c) 	(isalnum(c) || (c) == '_')

#define	LIBC_STRDUP(new, existing) \

	if ((new = libc_strdup(existing)) == NULL) { \

		dup_fail = 1; \

		goto barf_line; \

	}

/*

 * This file has all the routines that access the configuration

 * information.

 */

struct cons_cell_v1 { /* private to the parser */

	struct __nsw_switchconfig_v1 *sw;

	struct cons_cell_v1 *next;

};

struct cons_cell { /* private to the parser */

	struct __nsw_switchconfig *sw;

	struct cons_cell *next;

};

/*

 * Local routines

 */

static char *skip(char **, char);

static char *labelskip(char *);

static char *spaceskip(char *);

static struct __nsw_switchconfig_v1 *scrounge_cache_v1(const char *);

static struct __nsw_switchconfig *scrounge_cache(const char *);

static int add_concell_v1(struct __nsw_switchconfig_v1 *);

static int add_concell(struct __nsw_switchconfig *);

static void freeconf_v1(struct __nsw_switchconfig_v1 *);

static void freeconf(struct __nsw_switchconfig *);

static int alldigits(char *);

static struct cons_cell_v1 *concell_list_v1; /* stays with add_concell() */

static struct cons_cell *concell_list; /* stays with add_concell() */

/*

 *

 * With the "lookup control" feature, the default criteria for NIS, NIS+,

 * and any new services (e.g. ldap) will be:

 *     [SUCCESS=return  NOTFOUND=continue UNAVAIL=continue TRYAGAIN=forever]

 *

 * For backward compat, NIS via NIS server in DNS forwarding mode will be:

 *     [SUCCESS=return  NOTFOUND=continue UNAVAIL=continue TRYAGAIN=continue]

 *

 * And also for backward compat, the default criteria for DNS will be:

 *     [SUCCESS=return  NOTFOUND=continue UNAVAIL=continue TRYAGAIN=continue]

 */

/*

 * The BIND resolver normally will retry several times on server non-response.

 * But now with the "lookup control" feature, we don't want the resolver doing

 * many retries, rather we want it to return control (reasonably) quickly back

 * to the switch engine.  However, when TRYAGAIN=N or TRYAGAIN=forever is

 * not explicitly set by the admin in the conf file, we want the old "resolver

 * retry a few times" rather than no retries at all.

 */

static int 	dns_tryagain_retry = 3;

/*

 * For backward compat (pre "lookup control"), the dns default behavior is

 * soft lookup.

 */

static void

set_dns_default_lkp(struct __nsw_lookup_v1 *lkp)

{

	if (strcasecmp(lkp->service_name, "dns") == 0) {

		lkp->actions[__NSW_TRYAGAIN] = __NSW_TRYAGAIN_NTIMES;

		lkp->max_retries = dns_tryagain_retry;

	}

}

/*

 * Private interface used by nss_common.c, hence this function is not static

 */

struct __nsw_switchconfig_v1 *

_nsw_getoneconfig_v1(const char *name, char *linep, enum __nsw_parse_err *errp)

	/* linep   Nota Bene: not const char *	*/

	/* errp  Meanings are abused a bit	*/

{

	struct __nsw_switchconfig_v1 *cfp;

	struct __nsw_lookup_v1 *lkp, **lkq;

	int end_crit, dup_fail = 0;

	action_t act;

	char *p, *tokenp;

	*errp = __NSW_CONF_PARSE_SUCCESS;

	if ((cfp = libc_malloc(sizeof (struct __nsw_switchconfig_v1)))

	    == NULL) {

		*errp = __NSW_CONF_PARSE_SYSERR;

		return (NULL);

	}

	LIBC_STRDUP(cfp->dbase, name);

	lkq = &cfp->lookups;

	/* linep points to a naming service name */

	for (;;) {

		int i;

		/* white space following the last service */

		if (*linep == '\0' || *linep == '\n') {

			return (cfp);

		}

		if ((lkp = libc_malloc(sizeof (struct __nsw_lookup_v1)))

		    == NULL) {

			*errp = __NSW_CONF_PARSE_SYSERR;

			freeconf_v1(cfp);

			return (NULL);

		}

		*lkq = lkp;

		lkq = &lkp->next;

		for (i = 0; i < __NSW_STD_ERRS_V1; i++)

			if (i == __NSW_SUCCESS)

				lkp->actions[i] = __NSW_RETURN;

			else if (i == __NSW_TRYAGAIN)

				lkp->actions[i] = __NSW_TRYAGAIN_FOREVER;

			else

				lkp->actions[i] = __NSW_CONTINUE;

		/* get criteria for the naming service */

		if (tokenp = skip(&linep, '[')) { /* got criteria */

			/* premature end, illegal char following [ */

			if (!islabel(*linep))

				goto barf_line;

			LIBC_STRDUP(lkp->service_name, tokenp);

			cfp->num_lookups++;

			set_dns_default_lkp(lkp);

			end_crit = 0;

			/* linep points to a switch_err */

			for (;;) {

				int ntimes = 0; /* try again max N times */

				int dns_continue = 0;

				if ((tokenp = skip(&linep, '=')) == NULL) {

					goto barf_line;

				}

				/* premature end, ill char following = */

				if (!islabel(*linep))

					goto barf_line;

				/* linep points to the string following '=' */

				p = labelskip(linep);

				if (*p == ']')

					end_crit = 1;

				else if (*p != ' ' && *p != '\t')

					goto barf_line;

				*p++ = '\0'; /* null terminate linep */

				p = spaceskip(p);

				if (!end_crit) {

					if (*p == ']') {

					end_crit = 1;

					*p++ = '\0';

					} else if (*p == '\0' || *p == '\n') {

						return (cfp);

					} else if (!islabel(*p))

					/* p better be the next switch_err */

						goto barf_line;

				}

				if (strcasecmp(linep, __NSW_STR_RETURN) == 0)

					act = __NSW_RETURN;

				else if (strcasecmp(linep,

						    __NSW_STR_CONTINUE) == 0) {

					if (strcasecmp(lkp->service_name,

						    "dns") == 0 &&

						strcasecmp(tokenp,

							__NSW_STR_TRYAGAIN)

							== 0) {

						/*

						 * Add one more condition

						 * so it retries only if it's

						 * "dns [TRYAGAIN=continue]"

						 */

						dns_continue = 1;

						act = __NSW_TRYAGAIN_NTIMES;

					} else

						act = __NSW_CONTINUE;

				} else if (strcasecmp(linep,

					    __NSW_STR_FOREVER) == 0)

					act = __NSW_TRYAGAIN_FOREVER;

				else if (alldigits(linep)) {

					act = __NSW_TRYAGAIN_NTIMES;

					ntimes = atoi(linep);

					if (ntimes < 0 || ntimes > INT_MAX)

						ntimes = 0;

				}

				else

					goto barf_line;

				if (__NSW_SUCCESS_ACTION(act) &&

				    strcasecmp(tokenp,

					    __NSW_STR_SUCCESS) == 0) {

					lkp->actions[__NSW_SUCCESS] = act;

				} else if (__NSW_NOTFOUND_ACTION(act) &&

					strcasecmp(tokenp,

					    __NSW_STR_NOTFOUND) == 0) {

					lkp->actions[__NSW_NOTFOUND] = act;

				} else if (__NSW_UNAVAIL_ACTION(act) &&

					strcasecmp(tokenp,

					    __NSW_STR_UNAVAIL) == 0) {

					lkp->actions[__NSW_UNAVAIL] = act;

				} else if (__NSW_TRYAGAIN_ACTION(act) &&

					strcasecmp(tokenp,

					    __NSW_STR_TRYAGAIN) == 0) {

					lkp->actions[__NSW_TRYAGAIN] = act;

					if (strcasecmp(lkp->service_name,

						    "nis") == 0)

						lkp->actions[

						    __NSW_NISSERVDNS_TRYAGAIN]

						    = act;

					if (act == __NSW_TRYAGAIN_NTIMES)

						lkp->max_retries =

						dns_continue ?

						dns_tryagain_retry : ntimes;

				} else {

					/*EMPTY*/

					/*

					 * convert string tokenp to integer

					 * and put in long_errs

					 */

				}

				if (end_crit) {

					linep = spaceskip(p);

					if (*linep == '\0' || *linep == '\n')

						return (cfp);

					break; /* process next naming service */

				}

				linep = p;

			} /* end of while loop for a name service's criteria */

		} else {

			/*

			 * no criteria for this naming service.

			 * linep points to name service, but not null

			 * terminated.

			 */

			p = labelskip(linep);

			if (*p == '\0' || *p == '\n') {

				*p = '\0';

				LIBC_STRDUP(lkp->service_name, linep);

				set_dns_default_lkp(lkp);

				cfp->num_lookups++;

				return (cfp);

			}

			if (*p != ' ' && *p != '\t')

				goto barf_line;

			*p++ = '\0';

			LIBC_STRDUP(lkp->service_name, linep);

			set_dns_default_lkp(lkp);

			cfp->num_lookups++;

			linep = spaceskip(p);

		}

	} /* end of while(1) loop for a name service */

barf_line:

	freeconf_v1(cfp);

	*errp = dup_fail ? __NSW_CONF_PARSE_SYSERR : __NSW_CONF_PARSE_NOPOLICY;

	return (NULL);

}

/*

 * Private interface used by nss_common.c, hence this function is not static

 */

struct __nsw_switchconfig *

_nsw_getoneconfig(const char *name, char *linep, enum __nsw_parse_err *errp)

	/* linep   Nota Bene: not const char *	*/

	/* errp  Meanings are abused a bit	*/

{

	struct __nsw_switchconfig *cfp;

	struct __nsw_lookup *lkp, **lkq;

	int end_crit, dup_fail = 0;

	action_t act;

	char *p, *tokenp;

	*errp = __NSW_CONF_PARSE_SUCCESS;

	if ((cfp = libc_malloc(sizeof (struct __nsw_switchconfig)))

	    == NULL) {

		*errp = __NSW_CONF_PARSE_SYSERR;

		return (NULL);

	}

	LIBC_STRDUP(cfp->dbase, name);

	lkq = &cfp->lookups;

	/* linep points to a naming service name */

	for (;;) {

		int i;

		/* white space following the last service */

		if (*linep == '\0' || *linep == '\n') {

			return (cfp);

		}

		if ((lkp = libc_malloc(sizeof (struct __nsw_lookup)))

		    == NULL) {

			*errp = __NSW_CONF_PARSE_SYSERR;

			freeconf(cfp);

			return (NULL);

		}

		*lkq = lkp;

		lkq = &lkp->next;

		for (i = 0; i < __NSW_STD_ERRS; i++)

			if (i == __NSW_SUCCESS)

				lkp->actions[i] = 1;

			else

				lkp->actions[i] = 0;

		/* get criteria for the naming service */

		if (tokenp = skip(&linep, '[')) { /* got criteria */

			/* premature end, illegal char following [ */

			if (!islabel(*linep))

				goto barf_line;

			LIBC_STRDUP(lkp->service_name, tokenp);

			cfp->num_lookups++;

			end_crit = 0;

			/* linep points to a switch_err */

			for (;;) {

				if ((tokenp = skip(&linep, '=')) == NULL) {

					goto barf_line;

				}

				/* premature end, ill char following = */

				if (!islabel(*linep))

					goto barf_line;

				/* linep points to the string following '=' */

				p = labelskip(linep);

				if (*p == ']')

					end_crit = 1;

				else if (*p != ' ' && *p != '\t')

					goto barf_line;

				*p++ = '\0'; /* null terminate linep */

				p = spaceskip(p);

				if (!end_crit) {

					if (*p == ']') {

					end_crit = 1;

					*p++ = '\0';

					} else if (*p == '\0' || *p == '\n')

						return (cfp);

					else if (!islabel(*p))

					/* p better be the next switch_err */

						goto barf_line;

				}

				if (strcasecmp(linep, __NSW_STR_RETURN) == 0)

					act = __NSW_RETURN;

				else if (strcasecmp(linep,

					    __NSW_STR_CONTINUE) == 0)

					act = __NSW_CONTINUE;

				else if (strcasecmp(linep,

					    __NSW_STR_FOREVER) == 0)

					/*

					 * =forever or =N might be in conf file

					 * but old progs won't expect it.

					 */

					act = __NSW_RETURN;

				else if (alldigits(linep))

					act = __NSW_CONTINUE;

				else

					goto barf_line;

				if (strcasecmp(tokenp,

					    __NSW_STR_SUCCESS) == 0) {

					lkp->actions[__NSW_SUCCESS] = act;

				} else if (strcasecmp(tokenp,

					    __NSW_STR_NOTFOUND) == 0) {

					lkp->actions[__NSW_NOTFOUND] = act;

				} else if (strcasecmp(tokenp,

					    __NSW_STR_UNAVAIL) == 0) {

					lkp->actions[__NSW_UNAVAIL] = act;

				} else if (strcasecmp(tokenp,

					    __NSW_STR_TRYAGAIN) == 0) {

					lkp->actions[__NSW_TRYAGAIN] = act;

				} else {

					/*EMPTY*/

					/*

					 * convert string tokenp to integer

					 * and put in long_errs

					 */

				}

				if (end_crit) {

					linep = spaceskip(p);

					if (*linep == '\0' || *linep == '\n')

						return (cfp);

					break; /* process next naming service */

				}

				linep = p;

			} /* end of while loop for a name service's criteria */

		} else {

			/*

			 * no criteria for this naming service.

			 * linep points to name service, but not null

			 * terminated.

			 */

			p = labelskip(linep);

			if (*p == '\0' || *p == '\n') {

				*p = '\0';

				LIBC_STRDUP(lkp->service_name, linep);

				cfp->num_lookups++;

				return (cfp);

			}

			if (*p != ' ' && *p != '\t')

				goto barf_line;

			*p++ = '\0';

			LIBC_STRDUP(lkp->service_name, linep);

			cfp->num_lookups++;

			linep = spaceskip(p);

		}

	} /* end of while(1) loop for a name service */

barf_line:

	freeconf(cfp);

	*errp = dup_fail ? __NSW_CONF_PARSE_SYSERR : __NSW_CONF_PARSE_NOPOLICY;

	return (NULL);

}

static mutex_t serialize_config_v1 = DEFAULTMUTEX;

static mutex_t serialize_config = DEFAULTMUTEX;

static void

syslog_warning(const char *dbase)

{

	syslog(LOG_WARNING,

	    "libc: bad lookup policy for %s in %s, using defaults..\n",

	    dbase, __NSW_CONFIG_FILE);

}

/*

 * Since we cannot call malloc() or lock any of the ordinary mutexes

 * while we hold an lmutex_lock(), we open the file outside the lock

 * and disable locking on the file; the latter is fine because we're

 * reading the fp only from a single thread.

 */

static FILE *

open_conf(void)

{

	FILE *fp = fopen(__NSW_CONFIG_FILE, "rF");

	if (fp != NULL) {

		if (_findbuf(fp) == NULL) {

			(void) fclose(fp);

			return (NULL);

		}

		SET_IONOLOCK(fp);

	}

	return (fp);

}

struct __nsw_switchconfig_v1 *

__nsw_getconfig_v1(const char *dbase, enum __nsw_parse_err *errp)

{

	struct __nsw_switchconfig_v1 *cfp, *retp = NULL;

	int syslog_error = 0;

	FILE *fp = NULL;

	char *linep;

	char lineq[BUFSIZ];

	lmutex_lock(&serialize_config_v1);

top:

	if (cfp = scrounge_cache_v1(dbase)) {

		*errp = __NSW_CONF_PARSE_SUCCESS;