Import the first cut of my (finally finished) revnetgroup program. This

program parses the /etc/netgroup file into netgroup.byuser and netgroup.byhost
format for NIS.

I used hash tables to store the initial netgroup data in memory and to
construct the 'reverse' netgroup output. It seems just as fast as the
SunOS revnetgroup, which is surprising considering this is my first
attempt at using hash tables in a real application. :)

Note that I canibalized a large chunk of getnetgrent.c to save myself
from having to write my own netgroup parsing functions.

6 files changed, 951 insertions, 0 deletions

diff --git a/dist/libexec/revnetgroup/Makefile b/dist/libexec/revnetgroup/Makefile
new file mode 100644
index 0000000..dec0e7b
--- /dev/null
+++ b/dist/libexec/revnetgroup/Makefile
@@ -0,0 +1,8 @@
+#	$Id$
+
+PROG=	revnetgroup
+SRCS=	revnetgroup.c hash.c parse_netgroup.c
+
+MAN8= revnetgroup.8
+
+.include <bsd.prog.mk>
diff --git a/dist/libexec/revnetgroup/hash.c b/dist/libexec/revnetgroup/hash.c
new file mode 100644
index 0000000..b875843
--- /dev/null
+++ b/dist/libexec/revnetgroup/hash.c
@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 1995
+ *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Bill Paul.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$Id$
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include "hash.h"
+
+/*
+ * This hash function is stolen directly from the
+ * Berkeley DB package. It already exists inside libc, but
+ * it's declared static which prevents us from calling it
+ * from here.
+ */
+/*
+ * OZ's original sdbm hash
+ */
+u_int32_t
+hash(keyarg, len)
+	const void *keyarg;
+	register size_t len;
+{
+	register const u_char *key;
+	register size_t loop;
+	register u_int32_t h;
+
+#define HASHC   h = *key++ + 65599 * h
+
+	h = 0;
+	key = keyarg;
+	if (len > 0) {
+		loop = (len + 8 - 1) >> 3;
+
+		switch (len & (8 - 1)) {
+		case 0:
+			do {
+				HASHC;
+				/* FALLTHROUGH */
+		case 7:
+				HASHC;
+				/* FALLTHROUGH */
+		case 6:
+				HASHC;
+				/* FALLTHROUGH */
+		case 5:
+				HASHC;
+				/* FALLTHROUGH */
+		case 4:
+				HASHC;
+				/* FALLTHROUGH */
+		case 3:
+				HASHC;
+				/* FALLTHROUGH */
+		case 2:
+				HASHC;
+				/* FALLTHROUGH */
+		case 1:
+				HASHC;
+			} while (--loop);
+		}
+	}
+	return (h);
+}
+
+/*
+ * Generate a hash value for a given key (character string).
+ * We mask off all but the lower 8 bits since our table array
+ * can only hole 256 elements.
+ */
+u_int32_t hashkey(key)
+	char *key;
+{
+
+	if (key == NULL)
+		return (-1);
+	return(hash((void *)key, strlen(key)) & HASH_MASK);
+}
+
+/* Find an entry in the hash table (may be hanging off a linked list). */
+char *lookup(table, key)
+	struct group_entry *table[];
+	char *key;
+{
+	struct group_entry *cur;
+
+	cur = table[hashkey(key)];
+
+	while (cur) {
+		if (!strcmp(cur->key, key))
+			return(cur->data);
+		cur = cur->next;
+	}
+
+	return(NULL);
+}
+
+/*
+ * Store an entry in the main netgroup hash table. Here's how this
+ * works: the table can only be so big when we initialize it (TABLESIZE)
+ * but the number of netgroups in the /etc/netgroup file could easily be
+ * much larger than the table. Since our hash values are adjusted to
+ * never be greater than TABLESIZE too, this means it won't be long before
+ * we find ourselves with two keys that hash to the same value.
+ *
+ * One way to deal with this is to malloc(2) a second table and start
+ * doing indirection, but this is a pain in the butt and it's not worth
+ * going to all that trouble for a dinky littke program like this. Instead,
+ * we turn each table entry into a linked list and simply link keys
+ * with the same hash value together at the same index location within
+ * the table.
+ *
+ * That's a lot of comment for such a small piece of code, isn't it.
+ */
+void store (table, key, data)
+	struct group_entry *table[];
+	char *key, *data;
+{
+	struct group_entry *new;
+	u_int32_t i;
+
+	i = hashkey(key);
+
+	new = (struct group_entry *)malloc(sizeof(struct group_entry));
+	new->key = strdup(key);
+	new->data = strdup(data);
+	new->next = table[i];
+	table[i] = new;
+
+	return;
+}
+
+/*
+ * Store an group member entry and/or update its grouplist. This is
+ * a bit more complicated than the previous function since we have to
+ * maintain not only the hash table of group members, each group member
+ * structure also has a linked list of groups hung off it. If handed
+ * a member name that we haven't encountered before, we have to do
+ * two things: add that member to the table (possibly hanging them
+ * off the end of a linked list, as above), and add a group name to
+ * the member's grouplist list. If we're handed a name that already has
+ * an entry in the table, then we just have to do one thing, which is
+ * to update its grouplist.
+ */
+void mstore (table, key, data, domain)
+	struct member_entry *table[];
+	char *key, *data, *domain;
+{
+	struct member_entry *cur, *new;
+	struct grouplist *tmp;
+	u_int32_t i;
+
+	i = hashkey(key);
+	cur = table[i];
+
+	tmp = (struct grouplist *)malloc(sizeof(struct grouplist));
+	tmp->groupname = strdup(data);
+	tmp->next = NULL;
+
+	/* Check if all we have to do is insert a new groupname. */
+	while (cur) {
+		if (!strcmp(cur->key, key)) {
+			tmp->next = cur->groups;
+			cur->groups = tmp;
+			return;
+		}
+		cur = cur->next;
+	}
+
+	/* Didn't find a match -- add the whole mess to the table. */
+	new = (struct member_entry *)malloc(sizeof(struct member_entry));
+	new->key = strdup(key);
+	new->domain = domain ? strdup(domain) : "*";
+	new->groups = tmp;
+	new->next = table[i];
+	table[i] = new;
+
+	return;
+}
diff --git a/dist/libexec/revnetgroup/hash.h b/dist/libexec/revnetgroup/hash.h
new file mode 100644
index 0000000..2212534
--- /dev/null
+++ b/dist/libexec/revnetgroup/hash.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 1995
+ *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Bill Paul.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$Id$
+ */
+
+/* Groupname entry hung off a member_entry node. */
+struct grouplist {
+	char *groupname;
+	struct grouplist *next;
+};
+
+/* Entry in the cooked member list hash table. */
+struct member_entry {
+	char *key;
+	char *domain;
+	struct grouplist *groups;
+	struct member_entry *next;
+};
+
+/* Entry in the raw netgroup table. */
+struct group_entry {
+	char *key;
+	char *data;
+	struct grps *groups;
+	struct group_entry *next;
+};
+
+/* Table size (chosen arbitrarily). Not too big, not too small. */
+#define TABLESIZE 256
+#define HASH_MASK 0x000000FF
diff --git a/dist/libexec/revnetgroup/parse_netgroup.c b/dist/libexec/revnetgroup/parse_netgroup.c
new file mode 100644
index 0000000..99dfaeb
--- /dev/null
+++ b/dist/libexec/revnetgroup/parse_netgroup.c
@@ -0,0 +1,370 @@
+/*
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Rick Macklem at The University of Guelph.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "$Id$";
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * This is a specially hacked-up version of getnetgrent.c used to parse
+ * data from the stored hash table of netgroup info rather than from a
+ * file. It's used mainly for the parse_netgroup() function. All the YP
+ * stuff and file support has been stripped out since it isn't needed.
+ */
+
+#include <stdio.h>
+#include <strings.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "hash.h"
+
+/*
+ * Static Variables and functions used by setnetgrent(), getnetgrent() and
+ * __endnetgrent().
+ * There are two linked lists:
+ * - linelist is just used by setnetgrent() to parse the net group file via.
+ *   parse_netgrp()
+ * - netgrp is the list of entries for the current netgroup
+ */
+struct linelist {
+	struct linelist	*l_next;	/* Chain ptr. */
+	int		l_parsed;	/* Flag for cycles */
+	char		*l_groupname;	/* Name of netgroup */
+	char		*l_line;	/* Netgroup entrie(s) to be parsed */
+};
+
+struct netgrp {
+	struct netgrp	*ng_next;	/* Chain ptr */
+	char		*ng_str[3];	/* Field pointers, see below */
+};
+#define NG_HOST		0	/* Host name */
+#define NG_USER		1	/* User name */
+#define NG_DOM		2	/* and Domain name */
+
+static struct linelist	*linehead = (struct linelist *)0;
+static struct netgrp	*nextgrp = (struct netgrp *)0;
+static struct {
+	struct netgrp	*gr;
+	char		*grname;
+} grouphead = {
+	(struct netgrp *)0,
+	(char *)0,
+};
+static int parse_netgrp();
+static struct linelist *read_for_group();
+void __setnetgrent(), __endnetgrent();
+int __getnetgrent();
+extern struct group_entry *gtable[];
+extern char *lookup __P(( struct group_entry *[], char * ));
+#define	LINSIZ	1024	/* Length of netgroup file line */
+
+/*
+ * setnetgrent()
+ * Parse the netgroup file looking for the netgroup and build the list
+ * of netgrp structures. Let parse_netgrp() and read_for_group() do
+ * most of the work.
+ */
+void
+__setnetgrent(group)
+	char *group;
+{
+	/* Sanity check */
+
+	if (group == NULL || !strlen(group))
+		return;
+
+	if (grouphead.gr == (struct netgrp *)0 ||
+		strcmp(group, grouphead.grname)) {
+		__endnetgrent();
+		if (parse_netgrp(group))
+			__endnetgrent();
+		else {
+			grouphead.grname = (char *)
+				malloc(strlen(group) + 1);
+			strcpy(grouphead.grname, group);
+		}
+	}
+	nextgrp = grouphead.gr;
+}
+
+/*
+ * Get the next netgroup off the list.
+ */
+int
+__getnetgrent(hostp, userp, domp)
+	char **hostp, **userp, **domp;
+{
+	if (nextgrp) {
+		*hostp = nextgrp->ng_str[NG_HOST];
+		*userp = nextgrp->ng_str[NG_USER];
+		*domp = nextgrp->ng_str[NG_DOM];
+		nextgrp = nextgrp->ng_next;
+		return (1);
+	}
+	return (0);
+}
+
+/*
+ * __endnetgrent() - cleanup
+ */
+void
+__endnetgrent()
+{
+	register struct linelist *lp, *olp;
+	register struct netgrp *gp, *ogp;
+
+	lp = linehead;
+	while (lp) {
+		olp = lp;
+		lp = lp->l_next;
+		free(olp->l_groupname);
+		free(olp->l_line);
+		free((char *)olp);
+	}
+	linehead = (struct linelist *)0;
+	if (grouphead.grname) {
+		free(grouphead.grname);
+		grouphead.grname = (char *)0;
+	}
+	gp = grouphead.gr;
+	while (gp) {
+		ogp = gp;
+		gp = gp->ng_next;
+		if (ogp->ng_str[NG_HOST])
+			free(ogp->ng_str[NG_HOST]);
+		if (ogp->ng_str[NG_USER])
+			free(ogp->ng_str[NG_USER]);
+		if (ogp->ng_str[NG_DOM])
+			free(ogp->ng_str[NG_DOM]);
+		free((char *)ogp);
+	}
+	grouphead.gr = (struct netgrp *)0;
+}
+
+/*
+ * Parse the netgroup file setting up the linked lists.
+ */
+static int
+parse_netgrp(group)
+	char *group;
+{
+	register char *spos, *epos;
+	register int len, strpos;
+#ifdef DEBUG
+	register int fields;
+#endif
+	char *pos, *gpos;
+	struct netgrp *grp;
+	struct linelist *lp = linehead;
+
+	/*
+	 * First, see if the line has already been read in.
+	 */
+	while (lp) {
+		if (!strcmp(group, lp->l_groupname))
+			break;
+		lp = lp->l_next;
+	}
+	if (lp == (struct linelist *)0 &&
+	    (lp = read_for_group(group)) == (struct linelist *)0)
+		return (1);
+	if (lp->l_parsed) {
+#ifdef DEBUG
+		/*
+		 * This error message is largely superflous since the
+		 * code handles the error condition sucessfully, and
+		 * spewing it out from inside libc can actually hose
+		 * certain programs.
+		 */
+		fprintf(stderr, "Cycle in netgroup %s\n", lp->l_groupname);
+#endif
+		return (1);
+	} else
+		lp->l_parsed = 1;
+	pos = lp->l_line;
+	/* Watch for null pointer dereferences, dammit! */
+	while (pos != NULL && *pos != '\0') {
+		if (*pos == '(') {
+			grp = (struct netgrp *)malloc(sizeof (struct netgrp));
+			bzero((char *)grp, sizeof (struct netgrp));
+			grp->ng_next = grouphead.gr;
+			grouphead.gr = grp;
+			pos++;
+			gpos = strsep(&pos, ")");
+#ifdef DEBUG
+			fields = 0;
+#endif
+			for (strpos = 0; strpos < 3; strpos++) {
+				if ((spos = strsep(&gpos, ","))) {
+#ifdef DEBUG
+					fields++;
+#endif
+					while (*spos == ' ' || *spos == '\t')
+						spos++;
+					if ((epos = strpbrk(spos, " \t"))) {
+						*epos = '\0';
+						len = epos - spos;
+					} else
+						len = strlen(spos);
+					if (len > 0) {
+						grp->ng_str[strpos] =  (char *)
+							malloc(len + 1);
+						bcopy(spos, grp->ng_str[strpos],
+							len + 1);
+					}
+				} else {
+					/*
+					 * All other systems I've tested
+					 * return NULL for empty netgroup
+					 * fields. It's up to user programs
+					 * to handle the NULLs appropriately.
+					 */
+					grp->ng_str[strpos] = NULL;
+				}
+			}
+#ifdef DEBUG
+			/*
+			 * Note: on other platforms, malformed netgroup
+			 * entries are not normally flagged. While we
+			 * can catch bad entries and report them, we should
+			 * stay silent by default for compatibility's sake.
+			 */
+			if (fields < 3)
+					fprintf(stderr, "Bad entry (%s%s%s%s%s) in netgroup \"%s\"\n",
+						grp->ng_str[NG_HOST] == NULL ? "" : grp->ng_str[NG_HOST],
+						grp->ng_str[NG_USER] == NULL ? "" : ",",
+						grp->ng_str[NG_USER] == NULL ? "" : grp->ng_str[NG_USER],
+						grp->ng_str[NG_DOM] == NULL ? "" : ",",
+						grp->ng_str[NG_DOM] == NULL ? "" : grp->ng_str[NG_DOM],
+						lp->l_groupname);
+#endif
+		} else {
+			spos = strsep(&pos, ", \t");
+			if (parse_netgrp(spos))
+				continue;
+		}
+		/* Watch for null pointer dereferences, dammit! */
+		if (pos != NULL)
+			while (*pos == ' ' || *pos == ',' || *pos == '\t')
+				pos++;
+	}
+	return (0);
+}
+
+/*
+ * Read the netgroup file and save lines until the line for the netgroup
+ * is found. Return 1 if eof is encountered.
+ */
+static struct linelist *
+read_for_group(group)
+	char *group;
+{
+	register char *pos, *spos, *linep, *olinep;
+	register int len, olen;
+	int cont;
+	struct linelist *lp;
+	char line[LINSIZ + 1];
+	char *key = NULL, *data = NULL;
+
+	data = lookup (gtable, group);
+	sprintf(line, "%s %s", group, data);
+	pos = (char *)&line;
+#ifdef CANT_HAPPEN
+	if (*pos == '#')
+		continue;
+#endif
+	while (*pos == ' ' || *pos == '\t')
+		pos++;
+	spos = pos;
+	while (*pos != ' ' && *pos != '\t' && *pos != '\n' &&
+		*pos != '\0')
+		pos++;
+	len = pos - spos;
+	while (*pos == ' ' || *pos == '\t')
+		pos++;
+	if (*pos != '\n' && *pos != '\0') {
+		lp = (struct linelist *)malloc(sizeof (*lp));
+		lp->l_parsed = 0;
+		lp->l_groupname = (char *)malloc(len + 1);
+		bcopy(spos, lp->l_groupname, len);
+		*(lp->l_groupname + len) = '\0';
+		len = strlen(pos);
+		olen = 0;
+			/*
+			 * Loop around handling line continuations.
+			 */
+			do {
+				if (*(pos + len - 1) == '\n')
+					len--;
+				if (*(pos + len - 1) == '\\') {
+					len--;
+					cont = 1;
+				} else
+					cont = 0;
+				if (len > 0) {
+					linep = (char *)malloc(olen + len + 1);
+					if (olen > 0) {
+						bcopy(olinep, linep, olen);
+						free(olinep);
+					}
+					bcopy(pos, linep + olen, len);
+					olen += len;
+					*(linep + olen) = '\0';
+					olinep = linep;
+				}
+#ifdef CANT_HAPPEN
+				if (cont) {
+					if (fgets(line, LINSIZ, netf)) {
+						pos = line;
+						len = strlen(pos);
+					} else
+						cont = 0;
+				}
+#endif
+			} while (cont);
+		lp->l_line = linep;
+		lp->l_next = linehead;
+		linehead = lp;
+#ifdef CANT_HAPPEN
+		/*
+		 * If this is the one we wanted, we are done.
+		 */
+		if (!strcmp(lp->l_groupname, group))
+#endif
+			return (lp);
+	}
+	return ((struct linelist *)0);
+}
diff --git a/dist/libexec/revnetgroup/revnetgroup.8 b/dist/libexec/revnetgroup/revnetgroup.8
new file mode 100644
index 0000000..0a1330e
--- /dev/null
+++ b/dist/libexec/revnetgroup/revnetgroup.8
@@ -0,0 +1,137 @@
+.\" Copyright (c) 1995
+.\"	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by Bill Paul.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	$Id$
+.\"
+.Dd October 24, 1995
+.Dt REVNETGROUP 8
+.Os
+.Sh NAME
+.Nm revnetgroup
+.Nd "generate reverse netgroup data"
+.Sh SYNOPSIS
+.Nm revnetgroup
+.Fl u
+.Fl h
+.Op Fl f Ar netgroup_file
+.Sh DESCRIPTION
+.Nm revnetgroup
+processes the contents of a file in
+.Xr netgroup 5
+format into what is called
+.Pa reverse netgroup
+form. That is, where the original file shows
+netgroup memberships in terms of which members reside in a particular
+group, the reverse netgroup format specifies what groups are associated
+with a particular member. This information is used to generate the
+.Nm netgroup.byuser
+and
+.Nm netgroup.byhosts
+NIS maps. These reverse netgroup maps are used to help speed up
+netgroup lookups, particularly for the
+.Fn innetgr
+library function.
+.Pp
+For example, the standard
+.Nm /etc/netgroup
+file may list a netgroup and a list of its members. Here, the
+netgroup is considered the
+.Pa key
+and the member names are the
+.Pa data .
+By contrast, the reverse
+.Nm netgroup.byusers
+database lists each unique
+member as the key and the netgroups to which the members belong become
+the data. Seperate databases are created to hold information pertaining
+to users and hosts; this allows netgroup username lookups
+and netgroup hostname lookups to be performed using independent keyspaces.
+.Pp
+By constructing these reverse netgroup databases (and the corresponding
+NIS maps) in advance, the
+.Xr getnetgrent 3
+library functions are spared from having to work out the dependencies
+themselves on the fly. This is important on networks with large numbers
+of users and hosts, since it can take a considerable amount of time
+to process very large netgroup databases.
+.Pp
+The
+.Nm revnetgroup
+command prints its results on the standard output. It is usually called
+only by
+.Nm /var/yp/Makefile
+when rebuilding the NIS netgroup maps.
+.Pp
+.Sh OPTIONS
+The
+.Nm revnetgroup
+command supports the following options:
+.Bl -tag -width flag
+.It Fl u
+Generate netgroup.byuser output; only username information in the
+original netgroup file is processed.
+.It Fl h
+Generate netgroup.byhost output; only hostname information in the
+original netgroup file is processed. (Note at least one of the
+.Fl u
+or
+.Fl h
+flags must be specified.)
+.It Op Fl f Ar netgroup_file
+The
+.Nm revnetgroup
+command uses
+.Nm /etc/netgroup
+as its default input file. The
+.Fl f
+flag allows the user to specify an alternate input file. Specifying ``-''
+as the input file causes
+.Nm revnetgroup
+to read from the standard input.
+.El
+.Sh FILES
+.Bl -tag -width Pa -compact
+.It Pa /var/yp/Makefile
+The Makefile that calls
+.Nm yp_mkdb
+and
+.Nm revnetgroup
+to build the NIS databases.
+.It Pa /etc/netgroup
+The default netgroup database file. This file is most often found
+only on the NIS master server.
+.El
+.Sh SEE ALSO
+.Xr yp 4 ,
+.Xr netgroup 5 ,
+.Xr yp_mkdb 8 ,
+.Xr getnetgrent 3
+.Sh AUTHOR
+Bill Paul <wpaul@ctr.columbia.edu>
diff --git a/dist/libexec/revnetgroup/revnetgroup.c b/dist/libexec/revnetgroup/revnetgroup.c
new file mode 100644
index 0000000..4a3ab5a
--- /dev/null
+++ b/dist/libexec/revnetgroup/revnetgroup.c
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 1995
+ *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Bill Paul.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * reverse netgroup map generator program
+ *
+ * Written by Bill Paul <wpaul@ctr.columbia.edu>
+ * Center for Telecommunications Research
+ * Columbia University, New York City
+ *
+ *	$Id$
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "hash.h"
+
+#define LINSIZ 1024
+
+/* Default location of netgroup file. */
+char *netgroup = "/etc/netgroup";
+
+/* Stored hash table version of 'forward' netgroup database. */
+struct group_entry *gtable[TABLESIZE];
+
+/*
+ * Stored hash table of 'reverse' netgroup member database
+ * which we will construct.
+ */
+struct member_entry *mtable[TABLESIZE];
+
+extern void store __P(( struct group_entry ** , char *, char * ));
+extern void mstore __P(( struct member_entry ** , char *, char *, char * ));
+extern char *lookup __P(( struct group_entry **, char * ));
+
+void usage(prog)
+char *prog;
+{
+	fprintf (stderr,"usage: %s -u|-h [-f netgroup file]\n",prog);
+	exit(1);
+}
+
+extern char *optarg;
+
+main(argc, argv)
+int argc;
+char *argv[0];
+{
+	FILE *fp;
+	char readbuf[LINSIZ];
+	struct group_entry *gcur;
+	struct member_entry *mcur;
+	char *host, *user, *domain;
+	char ch;
+	char *key = NULL, *data = NULL;
+	int hosts, i;
+
+	if (argc < 2)
+		usage(argv[0]);
+
+	while ((ch = getopt(argc, argv, "uhf:")) != EOF) {
+		switch(ch) {
+		case 'u':
+			hosts = 0;
+			break;
+		case 'h':
+			hosts = 1;
+			break;
+		case 'f':
+			netgroup = optarg;
+			break;
+		default:
+			usage(argv[0]);
+			break;
+		}
+	}
+
+	if (strcmp(netgroup, "-")) {
+		if ((fp = fopen(netgroup, "r")) == NULL) {
+			perror(netgroup);
+			exit(1);
+		}
+	} else {
+		fp = stdin;
+	}
+
+	/* Stuff all the netgroup names and members into a hash table. */
+	while (fgets(readbuf, LINSIZ, fp)) {
+		if (readbuf[0] == '#')
+			continue;
+		if ((data = (char *)(strpbrk(readbuf, " \t") + 1)) < (char *)2)
+			continue;
+		key = (char *)&readbuf;
+		*(data - 1) = '\0';
+		store(gtable, key, data);
+	}
+
+	fclose(fp);
+
+	/*
+	 * Find all members of each netgroup and keep track of which
+	 * group they belong to.
+	 */
+	for (i = 0; i < TABLESIZE; i++) {
+		gcur = gtable[i];
+		while(gcur) {
+			__setnetgrent(gcur->key);
+			while(__getnetgrent(&host, &user, &domain) != NULL) {
+				if (hosts ? host && strcmp(host,"-") : user && strcmp(user, "-"))
+					mstore(mtable, hosts ? host : user, gcur->key, domain);
+			}
+			gcur = gcur->next;
+		}
+	}
+
+	/* Release resources used by the netgroup parser code. */
+	__endnetgrent();
+
+	/* Spew out the results. */
+	for (i = 0; i < TABLESIZE; i++) {
+		mcur = mtable[i];
+		while(mcur) {
+			struct grouplist *tmp;
+			printf ("%s.%s\t", mcur->key, mcur->domain);
+			tmp = mcur->groups;
+			while(tmp) {
+				printf ("%s", tmp->groupname);
+				tmp = tmp->next;
+				if (tmp)
+					printf(",");
+			}
+			mcur = mcur->next;
+			printf ("\n");
+		}
+	}
+
+	/* Let the OS free all our resources. */
+	exit(0);
+}