137 lines
3.7 KiB
C
137 lines
3.7 KiB
C
/*
|
|
* Routines for controlled evaluation of host names, user names, and so on.
|
|
* They are, in fact, wrappers around the functions that are specific for
|
|
* the sockets or TLI programming interfaces. The request_info and host_info
|
|
* structures are used for result cacheing.
|
|
*
|
|
* These routines allows us to postpone expensive operations until their
|
|
* results are really needed. Examples are hostname lookups and double
|
|
* checks, or username lookups. Information that cannot be retrieved is
|
|
* given the value "unknown" ("paranoid" in case of hostname problems).
|
|
*
|
|
* When ALWAYS_HOSTNAME is off, hostname lookup is done only when required by
|
|
* tcpd paranoid mode, by access control patterns, or by %letter expansions.
|
|
*
|
|
* When ALWAYS_RFC931 mode is off, user lookup is done only when required by
|
|
* access control patterns or %letter expansions.
|
|
*
|
|
* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char sccsid[] = "@(#) eval.c 1.3 95/01/30 19:51:45";
|
|
#endif
|
|
|
|
/* System libraries. */
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
/* Local stuff. */
|
|
|
|
#include "tcpd.h"
|
|
|
|
/*
|
|
* When a string has the value STRING_UNKNOWN, it means: don't bother, I
|
|
* tried to look up the data but it was unavailable for some reason. When a
|
|
* host name has the value STRING_PARANOID it means there was a name/address
|
|
* conflict.
|
|
*/
|
|
char unknown[] = STRING_UNKNOWN;
|
|
char paranoid[] = STRING_PARANOID;
|
|
|
|
/* eval_user - look up user name */
|
|
|
|
char *eval_user(request)
|
|
struct request_info *request;
|
|
{
|
|
if (request->user[0] == 0) {
|
|
(void)strncpy(request->user, unknown, sizeof(request->user) - 1);
|
|
if (request->sink == 0 && request->client->sin && request->server->sin)
|
|
rfc931(request->client->sin, request->server->sin, request->user);
|
|
}
|
|
return (request->user);
|
|
}
|
|
|
|
/* eval_hostaddr - look up printable address */
|
|
|
|
char *eval_hostaddr(host)
|
|
struct host_info *host;
|
|
{
|
|
if (host->addr[0] == 0) {
|
|
(void)strncpy(host->addr, unknown, sizeof(host->addr) - 1);
|
|
if (host->request->hostaddr != 0)
|
|
host->request->hostaddr(host);
|
|
}
|
|
return (host->addr);
|
|
}
|
|
|
|
/* eval_hostname - look up host name */
|
|
|
|
char *eval_hostname(host)
|
|
struct host_info *host;
|
|
{
|
|
if (host->name[0] == 0) {
|
|
(void)strncpy(host->name, unknown, sizeof(host->name) - 1);
|
|
if (host->request->hostname != 0)
|
|
host->request->hostname(host);
|
|
}
|
|
return (host->name);
|
|
}
|
|
|
|
/* eval_hostinfo - return string with host name (preferred) or address */
|
|
|
|
char *eval_hostinfo(host)
|
|
struct host_info *host;
|
|
{
|
|
char *hostname;
|
|
|
|
#ifndef ALWAYS_HOSTNAME /* no implicit host lookups */
|
|
if (host->name[0] == 0)
|
|
return (eval_hostaddr(host));
|
|
#endif
|
|
hostname = eval_hostname(host);
|
|
if (HOSTNAME_KNOWN(hostname)) {
|
|
return (host->name);
|
|
} else {
|
|
return (eval_hostaddr(host));
|
|
}
|
|
}
|
|
|
|
/* eval_client - return string with as much about the client as we know */
|
|
|
|
char *eval_client(request)
|
|
struct request_info *request;
|
|
{
|
|
static char both[2 * STRING_LENGTH];
|
|
char *hostinfo = eval_hostinfo(request->client);
|
|
|
|
#ifndef ALWAYS_RFC931 /* no implicit user lookups */
|
|
if (request->user[0] == 0)
|
|
return (hostinfo);
|
|
#endif
|
|
if (STR_NE(eval_user(request), unknown)) {
|
|
(void)snprintf(both, sizeof both, "%s@%s", request->user, hostinfo);
|
|
return (both);
|
|
} else {
|
|
return (hostinfo);
|
|
}
|
|
}
|
|
|
|
/* eval_server - return string with as much about the server as we know */
|
|
|
|
char *eval_server(request)
|
|
struct request_info *request;
|
|
{
|
|
static char both[2 * STRING_LENGTH];
|
|
char *host = eval_hostinfo(request->server);
|
|
char *daemon = eval_daemon(request);
|
|
|
|
if (STR_NE(host, unknown)) {
|
|
(void)snprintf(both, sizeof both, "%s@%s", daemon, host);
|
|
return (both);
|
|
} else {
|
|
return (daemon);
|
|
}
|
|
}
|