1 files changed, 277 insertions, 0 deletions
diff --git a/crypto/heimdal/appl/rsh/login_access.c b/crypto/heimdal/appl/rsh/login_access.c
new file mode 100644
index 0000000..e1bfe42e
--- /dev/null
+++ b/crypto/heimdal/appl/rsh/login_access.c
@@ -0,0 +1,277 @@
+/************************************************************************
+* Copyright 1995 by Wietse Venema.  All rights reserved.  Some individual
+* files may be covered by other copyrights.
+*
+* This material was originally written and compiled by Wietse Venema at
+* Eindhoven University of Technology, The Netherlands, in 1990, 1991,
+* 1992, 1993, 1994 and 1995.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that this entire copyright notice
+* is duplicated in all such copies.
+*
+* This software is provided "as is" and without any expressed or implied
+* warranties, including, without limitation, the implied warranties of
+* merchantibility and fitness for any particular purpose.
+************************************************************************/
+ /*
+  * This module implements a simple but effective form of login access
+  * control based on login names and on host (or domain) names, internet
+  * addresses (or network numbers), or on terminal line names in case of
+  * non-networked logins. Diagnostics are reported through syslog(3).
+  *
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#include "login_locl.h"
+
+RCSID("$Id: login_access.c 10020 2001-06-04 14:10:19Z assar $");
+
+ /* Delimiters for fields and for lists of users, ttys or hosts. */
+
+static char fs[] = ":";			/* field separator */
+static char sep[] = ", \t";		/* list-element separator */
+
+ /* Constants to be used in assignments only, not in comparisons... */
+
+#define YES             1
+#define NO              0
+
+ /*
+  * A structure to bundle up all login-related information to keep the
+  * functional interfaces as generic as possible.
+  */
+struct login_info {
+    struct passwd *user;
+    char   *from;
+};
+
+static int list_match(char *list, struct login_info *item,
+		      int (*match_fn)(char *, struct login_info *));
+static int user_match(char *tok, struct login_info *item);
+static int from_match(char *tok, struct login_info *item);
+static int string_match(char *tok, char *string);
+
+/* login_access - match username/group and host/tty with access control file */
+
+int login_access(struct passwd *user, char *from)
+{
+    struct login_info item;
+    FILE   *fp;
+    char    line[BUFSIZ];
+    char   *perm;			/* becomes permission field */
+    char   *users;			/* becomes list of login names */
+    char   *froms;			/* becomes list of terminals or hosts */
+    int     match = NO;
+    int     end;
+    int     lineno = 0;			/* for diagnostics */
+    char   *foo;
+
+    /*
+     * Bundle up the arguments to avoid unnecessary clumsiness lateron.
+     */
+    item.user = user;
+    item.from = from;
+
+    /*
+     * Process the table one line at a time and stop at the first match.
+     * Blank lines and lines that begin with a '#' character are ignored.
+     * Non-comment lines are broken at the ':' character. All fields are
+     * mandatory. The first field should be a "+" or "-" character. A
+     * non-existing table means no access control.
+     */
+
+    if ((fp = fopen(_PATH_LOGACCESS, "r")) != 0) {
+	while (!match && fgets(line, sizeof(line), fp)) {
+	    lineno++;
+	    if (line[end = strlen(line) - 1] != '\n') {
+		syslog(LOG_ERR, "%s: line %d: missing newline or line too long",
+		       _PATH_LOGACCESS, lineno);
+		continue;
+	    }
+	    if (line[0] == '#')
+		continue;			/* comment line */
+	    while (end > 0 && isspace((unsigned char)line[end - 1]))
+		end--;
+	    line[end] = 0;			/* strip trailing whitespace */
+	    if (line[0] == 0)			/* skip blank lines */
+		continue;
+	    foo = NULL;
+	    if (!(perm = strtok_r(line, fs, &foo))
+		|| !(users = strtok_r(NULL, fs, &foo))
+		|| !(froms = strtok_r(NULL, fs, &foo))
+		|| strtok_r(NULL, fs, &foo)) {
+		syslog(LOG_ERR, "%s: line %d: bad field count", 
+		       _PATH_LOGACCESS,
+		       lineno);
+		continue;
+	    }
+	    if (perm[0] != '+' && perm[0] != '-') {
+		syslog(LOG_ERR, "%s: line %d: bad first field", 
+		       _PATH_LOGACCESS,
+		       lineno);
+		continue;
+	    }
+	    match = (list_match(froms, &item, from_match)
+		     && list_match(users, &item, user_match));
+	}
+	fclose(fp);
+    } else if (errno != ENOENT) {
+	syslog(LOG_ERR, "cannot open %s: %m", _PATH_LOGACCESS);
+    }
+    return (match == 0 || (line[0] == '+'));
+}
+
+/* list_match - match an item against a list of tokens with exceptions */
+
+static int
+list_match(char *list,
+	   struct login_info *item,
+	   int (*match_fn)(char *, struct login_info *))
+{
+    char   *tok;
+    int     match = NO;
+    char   *foo = NULL;
+
+    /*
+     * Process tokens one at a time. We have exhausted all possible matches
+     * when we reach an "EXCEPT" token or the end of the list. If we do find
+     * a match, look for an "EXCEPT" list and recurse to determine whether
+     * the match is affected by any exceptions.
+     */
+
+    for (tok = strtok_r(list, sep, &foo);
+	 tok != NULL;
+	 tok = strtok_r(NULL, sep, &foo)) {
+	if (strcasecmp(tok, "EXCEPT") == 0)	/* EXCEPT: give up */
+	    break;
+	if ((match = (*match_fn) (tok, item)) != 0)	/* YES */
+	    break;
+    }
+    /* Process exceptions to matches. */
+
+    if (match != NO) {
+	while ((tok = strtok_r(NULL, sep, &foo)) && strcasecmp(tok, "EXCEPT"))
+	     /* VOID */ ;
+	if (tok == 0 || list_match(NULL, item, match_fn) == NO)
+	    return (match);
+    }
+    return (NO);
+}
+
+/* myhostname - figure out local machine name */
+
+static char *myhostname(void)
+{
+    static char name[MAXHOSTNAMELEN + 1] = "";
+
+    if (name[0] == 0) {
+	gethostname(name, sizeof(name));
+	name[MAXHOSTNAMELEN] = 0;
+    }
+    return (name);
+}
+
+/* netgroup_match - match group against machine or user */
+
+static int netgroup_match(char *group, char *machine, char *user)
+{
+#ifdef HAVE_YP_GET_DEFAULT_DOMAIN
+    static char *mydomain = 0;
+
+    if (mydomain == 0)
+	yp_get_default_domain(&mydomain);
+    return (innetgr(group, machine, user, mydomain));
+#else
+    syslog(LOG_ERR, "NIS netgroup support not configured");
+    return 0;
+#endif
+}
+
+/* user_match - match a username against one token */
+
+static int user_match(char *tok, struct login_info *item)
+{
+    char   *string = item->user->pw_name;
+    struct login_info fake_item;
+    struct group *group;
+    int     i;
+    char   *at;
+
+    /*
+     * If a token has the magic value "ALL" the match always succeeds.
+     * Otherwise, return YES if the token fully matches the username, if the
+     * token is a group that contains the username, or if the token is the
+     * name of the user's primary group.
+     */
+
+    if ((at = strchr(tok + 1, '@')) != 0) {	/* split user@host pattern */
+	*at = 0;
+	fake_item.from = myhostname();
+	return (user_match(tok, item) && from_match(at + 1, &fake_item));
+    } else if (tok[0] == '@') {			/* netgroup */
+	return (netgroup_match(tok + 1, (char *) 0, string));
+    } else if (string_match(tok, string)) {	/* ALL or exact match */
+	return (YES);
+    } else if ((group = getgrnam(tok)) != 0) { /* try group membership */
+	if (item->user->pw_gid == group->gr_gid)
+	    return (YES);
+	for (i = 0; group->gr_mem[i]; i++)
+	    if (strcasecmp(string, group->gr_mem[i]) == 0)
+		return (YES);
+    }
+    return (NO);
+}
+
+/* from_match - match a host or tty against a list of tokens */
+
+static int from_match(char *tok, struct login_info *item)
+{
+    char   *string = item->from;
+    int     tok_len;
+    int     str_len;
+
+    /*
+     * If a token has the magic value "ALL" the match always succeeds. Return
+     * YES if the token fully matches the string. If the token is a domain
+     * name, return YES if it matches the last fields of the string. If the
+     * token has the magic value "LOCAL", return YES if the string does not
+     * contain a "." character. If the token is a network number, return YES
+     * if it matches the head of the string.
+     */
+
+    if (tok[0] == '@') {			/* netgroup */
+	return (netgroup_match(tok + 1, string, (char *) 0));
+    } else if (string_match(tok, string)) {	/* ALL or exact match */
+	return (YES);
+    } else if (tok[0] == '.') {			/* domain: match last fields */
+	if ((str_len = strlen(string)) > (tok_len = strlen(tok))
+	    && strcasecmp(tok, string + str_len - tok_len) == 0)
+	    return (YES);
+    } else if (strcasecmp(tok, "LOCAL") == 0) {	/* local: no dots */
+	if (strchr(string, '.') == 0)
+	    return (YES);
+    } else if (tok[(tok_len = strlen(tok)) - 1] == '.'	/* network */
+	       && strncmp(tok, string, tok_len) == 0) {
+	return (YES);
+    }
+    return (NO);
+}
+
+/* string_match - match a string against one token */
+
+static int string_match(char *tok, char *string)
+{
+
+    /*
+     * If the token has the magic value "ALL" the match always succeeds.
+     * Otherwise, return YES if the token fully matches the string.
+     */
+
+    if (strcasecmp(tok, "ALL") == 0) {		/* all: always matches */
+	return (YES);
+    } else if (strcasecmp(tok, string) == 0) {	/* try exact match */
+	return (YES);
+    }
+    return (NO);
+}