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-rw-r--r--contrib/tcp_wrappers/hosts_access.c331
1 files changed, 0 insertions, 331 deletions
diff --git a/contrib/tcp_wrappers/hosts_access.c b/contrib/tcp_wrappers/hosts_access.c
deleted file mode 100644
index 9bdc7bcd66e9d..0000000000000
--- a/contrib/tcp_wrappers/hosts_access.c
+++ /dev/null
@@ -1,331 +0,0 @@
- /*
- * This module implements a simple access control language that is based on
- * host (or domain) names, NIS (host) netgroup names, IP addresses (or
- * network numbers) and daemon process names. When a match is found the
- * search is terminated, and depending on whether PROCESS_OPTIONS is defined,
- * a list of options is executed or an optional shell command is executed.
- *
- * Host and user names are looked up on demand, provided that suitable endpoint
- * information is available as sockaddr_in structures or TLI netbufs. As a
- * side effect, the pattern matching process may change the contents of
- * request structure fields.
- *
- * Diagnostics are reported through syslog(3).
- *
- * Compile with -DNETGROUP if your library provides support for netgroups.
- *
- * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
- */
-
-#ifndef lint
-static char sccsid[] = "@(#) hosts_access.c 1.21 97/02/12 02:13:22";
-#endif
-
-/* System libraries. */
-
-#include <sys/types.h>
-#include <sys/param.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <stdio.h>
-#include <syslog.h>
-#include <ctype.h>
-#include <errno.h>
-#include <setjmp.h>
-#include <string.h>
-
-extern char *fgets();
-extern int errno;
-
-#ifndef INADDR_NONE
-#define INADDR_NONE (-1) /* XXX should be 0xffffffff */
-#endif
-
-/* Local stuff. */
-
-#include "tcpd.h"
-
-/* Error handling. */
-
-extern jmp_buf tcpd_buf;
-
-/* Delimiters for lists of daemons or clients. */
-
-static char sep[] = ", \t\r\n";
-
-/* Constants to be used in assignments only, not in comparisons... */
-
-#define YES 1
-#define NO 0
-
- /*
- * These variables are globally visible so that they can be redirected in
- * verification mode.
- */
-
-char *hosts_allow_table = HOSTS_ALLOW;
-char *hosts_deny_table = HOSTS_DENY;
-int hosts_access_verbose = 0;
-
- /*
- * In a long-running process, we are not at liberty to just go away.
- */
-
-int resident = (-1); /* -1, 0: unknown; +1: yes */
-
-/* Forward declarations. */
-
-static int table_match();
-static int list_match();
-static int server_match();
-static int client_match();
-static int host_match();
-static int string_match();
-static int masked_match();
-
-/* Size of logical line buffer. */
-
-#define BUFLEN 2048
-
-/* hosts_access - host access control facility */
-
-int hosts_access(request)
-struct request_info *request;
-{
- int verdict;
-
- /*
- * If the (daemon, client) pair is matched by an entry in the file
- * /etc/hosts.allow, access is granted. Otherwise, if the (daemon,
- * client) pair is matched by an entry in the file /etc/hosts.deny,
- * access is denied. Otherwise, access is granted. A non-existent
- * access-control file is treated as an empty file.
- *
- * After a rule has been matched, the optional language extensions may
- * decide to grant or refuse service anyway. Or, while a rule is being
- * processed, a serious error is found, and it seems better to play safe
- * and deny service. All this is done by jumping back into the
- * hosts_access() routine, bypassing the regular return from the
- * table_match() function calls below.
- */
-
- if (resident <= 0)
- resident++;
- verdict = setjmp(tcpd_buf);
- if (verdict != 0)
- return (verdict == AC_PERMIT);
- if (table_match(hosts_allow_table, request))
- return (YES);
- if (table_match(hosts_deny_table, request))
- return (NO);
- return (YES);
-}
-
-/* table_match - match table entries with (daemon, client) pair */
-
-static int table_match(table, request)
-char *table;
-struct request_info *request;
-{
- FILE *fp;
- char sv_list[BUFLEN]; /* becomes list of daemons */
- char *cl_list; /* becomes list of clients */
- char *sh_cmd; /* becomes optional shell command */
- int match = NO;
- struct tcpd_context saved_context;
-
- saved_context = tcpd_context; /* stupid compilers */
-
- /*
- * Between the fopen() and fclose() calls, avoid jumps that may cause
- * file descriptor leaks.
- */
-
- if ((fp = fopen(table, "r")) != 0) {
- tcpd_context.file = table;
- tcpd_context.line = 0;
- while (match == NO && xgets(sv_list, sizeof(sv_list), fp) != 0) {
- if (sv_list[strlen(sv_list) - 1] != '\n') {
- tcpd_warn("missing newline or line too long");
- continue;
- }
- if (sv_list[0] == '#' || sv_list[strspn(sv_list, " \t\r\n")] == 0)
- continue;
- if ((cl_list = split_at(sv_list, ':')) == 0) {
- tcpd_warn("missing \":\" separator");
- continue;
- }
- sh_cmd = split_at(cl_list, ':');
- match = list_match(sv_list, request, server_match)
- && list_match(cl_list, request, client_match);
- }
- (void) fclose(fp);
- } else if (errno != ENOENT) {
- tcpd_warn("cannot open %s: %m", table);
- }
- if (match) {
- if (hosts_access_verbose > 1)
- syslog(LOG_DEBUG, "matched: %s line %d",
- tcpd_context.file, tcpd_context.line);
- if (sh_cmd) {
-#ifdef PROCESS_OPTIONS
- process_options(sh_cmd, request);
-#else
- char cmd[BUFSIZ];
- shell_cmd(percent_x(cmd, sizeof(cmd), sh_cmd, request));
-#endif
- }
- }
- tcpd_context = saved_context;
- return (match);
-}
-
-/* list_match - match a request against a list of patterns with exceptions */
-
-static int list_match(list, request, match_fn)
-char *list;
-struct request_info *request;
-int (*match_fn) ();
-{
- char *tok;
-
- /*
- * 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(list, sep); tok != 0; tok = strtok((char *) 0, sep)) {
- if (STR_EQ(tok, "EXCEPT")) /* EXCEPT: give up */
- return (NO);
- if (match_fn(tok, request)) { /* YES: look for exceptions */
- while ((tok = strtok((char *) 0, sep)) && STR_NE(tok, "EXCEPT"))
- /* VOID */ ;
- return (tok == 0 || list_match((char *) 0, request, match_fn) == 0);
- }
- }
- return (NO);
-}
-
-/* server_match - match server information */
-
-static int server_match(tok, request)
-char *tok;
-struct request_info *request;
-{
- char *host;
-
- if ((host = split_at(tok + 1, '@')) == 0) { /* plain daemon */
- return (string_match(tok, eval_daemon(request)));
- } else { /* daemon@host */
- return (string_match(tok, eval_daemon(request))
- && host_match(host, request->server));
- }
-}
-
-/* client_match - match client information */
-
-static int client_match(tok, request)
-char *tok;
-struct request_info *request;
-{
- char *host;
-
- if ((host = split_at(tok + 1, '@')) == 0) { /* plain host */
- return (host_match(tok, request->client));
- } else { /* user@host */
- return (host_match(host, request->client)
- && string_match(tok, eval_user(request)));
- }
-}
-
-/* host_match - match host name and/or address against pattern */
-
-static int host_match(tok, host)
-char *tok;
-struct host_info *host;
-{
- char *mask;
-
- /*
- * This code looks a little hairy because we want to avoid unnecessary
- * hostname lookups.
- *
- * The KNOWN pattern requires that both address AND name be known; some
- * patterns are specific to host names or to host addresses; all other
- * patterns are satisfied when either the address OR the name match.
- */
-
- if (tok[0] == '@') { /* netgroup: look it up */
-#ifdef NETGROUP
- static char *mydomain = 0;
- if (mydomain == 0)
- yp_get_default_domain(&mydomain);
- return (innetgr(tok + 1, eval_hostname(host), (char *) 0, mydomain));
-#else
- tcpd_warn("netgroup support is disabled"); /* not tcpd_jump() */
- return (NO);
-#endif
- } else if (STR_EQ(tok, "KNOWN")) { /* check address and name */
- char *name = eval_hostname(host);
- return (STR_NE(eval_hostaddr(host), unknown) && HOSTNAME_KNOWN(name));
- } else if (STR_EQ(tok, "LOCAL")) { /* local: no dots in name */
- char *name = eval_hostname(host);
- return (strchr(name, '.') == 0 && HOSTNAME_KNOWN(name));
- } else if ((mask = split_at(tok, '/')) != 0) { /* net/mask */
- return (masked_match(tok, mask, eval_hostaddr(host)));
- } else { /* anything else */
- return (string_match(tok, eval_hostaddr(host))
- || (NOT_INADDR(tok) && string_match(tok, eval_hostname(host))));
- }
-}
-
-/* string_match - match string against pattern */
-
-static int string_match(tok, string)
-char *tok;
-char *string;
-{
- int n;
-
- if (tok[0] == '.') { /* suffix */
- n = strlen(string) - strlen(tok);
- return (n > 0 && STR_EQ(tok, string + n));
- } else if (STR_EQ(tok, "ALL")) { /* all: match any */
- return (YES);
- } else if (STR_EQ(tok, "KNOWN")) { /* not unknown */
- return (STR_NE(string, unknown));
- } else if (tok[(n = strlen(tok)) - 1] == '.') { /* prefix */
- return (STRN_EQ(tok, string, n));
- } else { /* exact match */
- return (STR_EQ(tok, string));
- }
-}
-
-/* masked_match - match address against netnumber/netmask */
-
-static int masked_match(net_tok, mask_tok, string)
-char *net_tok;
-char *mask_tok;
-char *string;
-{
- unsigned long net;
- unsigned long mask;
- unsigned long addr;
-
- /*
- * Disallow forms other than dotted quad: the treatment that inet_addr()
- * gives to forms with less than four components is inconsistent with the
- * access control language. John P. Rouillard <rouilj@cs.umb.edu>.
- */
-
- if ((addr = dot_quad_addr(string)) == INADDR_NONE)
- return (NO);
- if ((net = dot_quad_addr(net_tok)) == INADDR_NONE
- || (mask = dot_quad_addr(mask_tok)) == INADDR_NONE) {
- tcpd_warn("bad net/mask expression: %s/%s", net_tok, mask_tok);
- return (NO); /* not tcpd_jump() */
- }
- return ((addr & mask) == net);
-}
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