1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * Copyright 2001 Sun Microsystems, Inc. All rights reserved. 3*0Sstevel@tonic-gate * Use is subject to license terms. 4*0Sstevel@tonic-gate */ 5*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 6*0Sstevel@tonic-gate 7*0Sstevel@tonic-gate /* 8*0Sstevel@tonic-gate * Routines for controlled evaluation of host names, user names, and so on. 9*0Sstevel@tonic-gate * They are, in fact, wrappers around the functions that are specific for 10*0Sstevel@tonic-gate * the sockets or TLI programming interfaces. The request_info and host_info 11*0Sstevel@tonic-gate * structures are used for result cacheing. 12*0Sstevel@tonic-gate * 13*0Sstevel@tonic-gate * These routines allows us to postpone expensive operations until their 14*0Sstevel@tonic-gate * results are really needed. Examples are hostname lookups and double 15*0Sstevel@tonic-gate * checks, or username lookups. Information that cannot be retrieved is 16*0Sstevel@tonic-gate * given the value "unknown" ("paranoid" in case of hostname problems). 17*0Sstevel@tonic-gate * 18*0Sstevel@tonic-gate * When ALWAYS_HOSTNAME is off, hostname lookup is done only when required by 19*0Sstevel@tonic-gate * tcpd paranoid mode, by access control patterns, or by %letter expansions. 20*0Sstevel@tonic-gate * 21*0Sstevel@tonic-gate * When ALWAYS_RFC931 mode is off, user lookup is done only when required by 22*0Sstevel@tonic-gate * access control patterns or %letter expansions. 23*0Sstevel@tonic-gate * 24*0Sstevel@tonic-gate * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate #ifndef lint 28*0Sstevel@tonic-gate static char sccsid[] = "@(#) eval.c 1.3 95/01/30 19:51:45"; 29*0Sstevel@tonic-gate #endif 30*0Sstevel@tonic-gate 31*0Sstevel@tonic-gate /* System libraries. */ 32*0Sstevel@tonic-gate 33*0Sstevel@tonic-gate #include <stdio.h> 34*0Sstevel@tonic-gate #include <string.h> 35*0Sstevel@tonic-gate 36*0Sstevel@tonic-gate /* Local stuff. */ 37*0Sstevel@tonic-gate 38*0Sstevel@tonic-gate #include "tcpd.h" 39*0Sstevel@tonic-gate 40*0Sstevel@tonic-gate /* 41*0Sstevel@tonic-gate * When a string has the value STRING_UNKNOWN, it means: don't bother, I 42*0Sstevel@tonic-gate * tried to look up the data but it was unavailable for some reason. When a 43*0Sstevel@tonic-gate * host name has the value STRING_PARANOID it means there was a name/address 44*0Sstevel@tonic-gate * conflict. 45*0Sstevel@tonic-gate */ 46*0Sstevel@tonic-gate char unknown[] = STRING_UNKNOWN; 47*0Sstevel@tonic-gate char paranoid[] = STRING_PARANOID; 48*0Sstevel@tonic-gate 49*0Sstevel@tonic-gate /* eval_user - look up user name */ 50*0Sstevel@tonic-gate 51*0Sstevel@tonic-gate char *eval_user(request) 52*0Sstevel@tonic-gate struct request_info *request; 53*0Sstevel@tonic-gate { 54*0Sstevel@tonic-gate if (request->user[0] == 0) { 55*0Sstevel@tonic-gate strcpy(request->user, unknown); 56*0Sstevel@tonic-gate if (request->sink == 0 && request->client->sin && request->server->sin) 57*0Sstevel@tonic-gate rfc931(request->client->sin, request->server->sin, request->user); 58*0Sstevel@tonic-gate } 59*0Sstevel@tonic-gate return (request->user); 60*0Sstevel@tonic-gate } 61*0Sstevel@tonic-gate 62*0Sstevel@tonic-gate /* eval_hostaddr - look up printable address */ 63*0Sstevel@tonic-gate 64*0Sstevel@tonic-gate char *eval_hostaddr(host) 65*0Sstevel@tonic-gate struct host_info *host; 66*0Sstevel@tonic-gate { 67*0Sstevel@tonic-gate if (host->addr[0] == 0) { 68*0Sstevel@tonic-gate strcpy(host->addr, unknown); 69*0Sstevel@tonic-gate if (host->request->hostaddr != 0) 70*0Sstevel@tonic-gate host->request->hostaddr(host); 71*0Sstevel@tonic-gate } 72*0Sstevel@tonic-gate return (host->addr); 73*0Sstevel@tonic-gate } 74*0Sstevel@tonic-gate 75*0Sstevel@tonic-gate /* eval_hostname - look up host name */ 76*0Sstevel@tonic-gate 77*0Sstevel@tonic-gate char *eval_hostname(host) 78*0Sstevel@tonic-gate struct host_info *host; 79*0Sstevel@tonic-gate { 80*0Sstevel@tonic-gate if (host->name[0] == 0) { 81*0Sstevel@tonic-gate strcpy(host->name, unknown); 82*0Sstevel@tonic-gate if (host->request->hostname != 0) 83*0Sstevel@tonic-gate host->request->hostname(host); 84*0Sstevel@tonic-gate } 85*0Sstevel@tonic-gate return (host->name); 86*0Sstevel@tonic-gate } 87*0Sstevel@tonic-gate 88*0Sstevel@tonic-gate /* eval_hostinfo - return string with host name (preferred) or address */ 89*0Sstevel@tonic-gate 90*0Sstevel@tonic-gate char *eval_hostinfo(host) 91*0Sstevel@tonic-gate struct host_info *host; 92*0Sstevel@tonic-gate { 93*0Sstevel@tonic-gate char *hostname; 94*0Sstevel@tonic-gate 95*0Sstevel@tonic-gate #ifndef ALWAYS_HOSTNAME /* no implicit host lookups */ 96*0Sstevel@tonic-gate if (host->name[0] == 0) 97*0Sstevel@tonic-gate return (eval_hostaddr(host)); 98*0Sstevel@tonic-gate #endif 99*0Sstevel@tonic-gate hostname = eval_hostname(host); 100*0Sstevel@tonic-gate if (HOSTNAME_KNOWN(hostname)) { 101*0Sstevel@tonic-gate return (host->name); 102*0Sstevel@tonic-gate } else { 103*0Sstevel@tonic-gate return (eval_hostaddr(host)); 104*0Sstevel@tonic-gate } 105*0Sstevel@tonic-gate } 106*0Sstevel@tonic-gate 107*0Sstevel@tonic-gate /* eval_client - return string with as much about the client as we know */ 108*0Sstevel@tonic-gate 109*0Sstevel@tonic-gate char *eval_client(request) 110*0Sstevel@tonic-gate struct request_info *request; 111*0Sstevel@tonic-gate { 112*0Sstevel@tonic-gate static char both[2 * STRING_LENGTH]; 113*0Sstevel@tonic-gate char *hostinfo = eval_hostinfo(request->client); 114*0Sstevel@tonic-gate 115*0Sstevel@tonic-gate #ifndef ALWAYS_RFC931 /* no implicit user lookups */ 116*0Sstevel@tonic-gate if (request->user[0] == 0) 117*0Sstevel@tonic-gate return (hostinfo); 118*0Sstevel@tonic-gate #endif 119*0Sstevel@tonic-gate if (STR_NE(eval_user(request), unknown)) { 120*0Sstevel@tonic-gate sprintf(both, "%s@%s", request->user, hostinfo); 121*0Sstevel@tonic-gate return (both); 122*0Sstevel@tonic-gate } else { 123*0Sstevel@tonic-gate return (hostinfo); 124*0Sstevel@tonic-gate } 125*0Sstevel@tonic-gate } 126*0Sstevel@tonic-gate 127*0Sstevel@tonic-gate /* eval_server - return string with as much about the server as we know */ 128*0Sstevel@tonic-gate 129*0Sstevel@tonic-gate char *eval_server(request) 130*0Sstevel@tonic-gate struct request_info *request; 131*0Sstevel@tonic-gate { 132*0Sstevel@tonic-gate static char both[2 * STRING_LENGTH]; 133*0Sstevel@tonic-gate char *host = eval_hostinfo(request->server); 134*0Sstevel@tonic-gate char *daemon = eval_daemon(request); 135*0Sstevel@tonic-gate 136*0Sstevel@tonic-gate if (STR_NE(host, unknown)) { 137*0Sstevel@tonic-gate sprintf(both, "%s@%s", daemon, host); 138*0Sstevel@tonic-gate return (both); 139*0Sstevel@tonic-gate } else { 140*0Sstevel@tonic-gate return (daemon); 141*0Sstevel@tonic-gate } 142*0Sstevel@tonic-gate } 143