1 /*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char sccsid[] = "@(#)klogin.c 5.6 (Berkeley) 03/29/91"; 10 #endif /* not lint */ 11 12 #ifdef KERBEROS 13 #include <sys/param.h> 14 #include <sys/syslog.h> 15 #include <kerberosIV/des.h> 16 #include <kerberosIV/krb.h> 17 #include <pwd.h> 18 #include <netdb.h> 19 20 #define PRINCIPAL_NAME pw->pw_name 21 #define PRINCIPAL_INST (rootlogin ? "root" : "") 22 #define INITIAL_TICKET "krbtgt" 23 #define VERIFY_SERVICE "rcmd" 24 25 extern int notickets; 26 extern int rootlogin; 27 28 /* 29 * Attempt to log the user in using Kerberos authentication 30 * 31 * return 0 on success (will be logged in) 32 * 1 if Kerberos failed (try local password in login) 33 */ 34 35 klogin(pw, localhost, password) 36 struct passwd *pw; 37 char *localhost, *password; 38 { 39 int kerror; 40 AUTH_DAT authdata; 41 KTEXT_ST ticket; 42 struct hostent *hp; 43 unsigned long faddr; 44 char realm[REALM_SZ], savehost[MAXHOSTNAMELEN]; 45 char tkt_location[MAXPATHLEN]; 46 47 /* 48 * If we aren't Kerberos-authenticated, try the normal pw file 49 * for a password. If that's ok, log the user in without issueing 50 * any tickets. 51 */ 52 if (krb_get_lrealm(realm, 0) != KSUCCESS) { 53 syslog(LOG_ERR, "couldn't get local Kerberos realm"); 54 return(1); 55 } 56 57 /* 58 * get TGT for local realm 59 * tickets are stored in a file determined by calling tkt_string() 60 */ 61 62 (void)sprintf(tkt_location, "%s%d", TKT_ROOT, pw->pw_uid); 63 (void)krb_set_tkt_string(tkt_location); 64 65 kerror = krb_get_pw_in_tkt(PRINCIPAL_NAME, PRINCIPAL_INST, 66 realm, INITIAL_TICKET, realm, DEFAULT_TKT_LIFE, password); 67 /* 68 * If we got a TGT, get a local "rcmd" ticket and check it so as to 69 * ensure that we are not talking to a bogus Kerberos server. 70 * 71 * There are 2 cases where we still allow a login: 72 * 1: the VERIFY_SERVICE doesn't exist in the KDC 73 * 2: local host has no srvtab, as (hopefully) indicated by a 74 * return value of RD_AP_UNDEC from krb_rd_req(). 75 */ 76 if (kerror != INTK_OK) { 77 if (kerror != INTK_BADPW && kerror != KDC_PR_UNKNOWN) { 78 syslog(LOG_ERR, "Kerberos intkt error: %s", 79 krb_err_txt[kerror]); 80 dest_tkt(); 81 } 82 return(1); 83 } 84 85 if (chown(TKT_FILE, pw->pw_uid, pw->pw_gid) < 0) 86 syslog(LOG_ERR, "chown tkfile (%s): %m", TKT_FILE); 87 88 (void)strncpy(savehost, krb_get_phost(localhost), sizeof(savehost)); 89 savehost[sizeof(savehost)-1] = NULL; 90 91 /* 92 * if the "VERIFY_SERVICE" doesn't exist in the KDC for this host, 93 * still allow login with tickets, but log the error condition. 94 */ 95 96 kerror = krb_mk_req(&ticket, VERIFY_SERVICE, savehost, realm, 33); 97 if (kerror == KDC_PR_UNKNOWN) { 98 syslog(LOG_NOTICE, "warning: TGT not verified (%s)", 99 krb_err_txt[kerror]); 100 notickets = 0; 101 return(0); 102 } 103 104 if (kerror != KSUCCESS) { 105 (void)printf("unable to use TGT: (%s)\n", krb_err_txt[kerror]); 106 syslog(LOG_NOTICE, "unable to use TGT: (%s)", 107 krb_err_txt[kerror]); 108 dest_tkt(); 109 return(1); 110 } 111 112 if (!(hp = gethostbyname(localhost))) { 113 syslog(LOG_ERR, "couldn't get local host address"); 114 dest_tkt(); 115 return(1); 116 } 117 118 bcopy((void *)hp->h_addr, (void *)&faddr, sizeof(faddr)); 119 120 kerror = krb_rd_req(&ticket, VERIFY_SERVICE, savehost, faddr, 121 &authdata, ""); 122 123 if (kerror == KSUCCESS) { 124 notickets = 0; 125 return(0); 126 } 127 128 /* undecipherable: probably didn't have a srvtab on the local host */ 129 if (kerror = RD_AP_UNDEC) { 130 syslog(LOG_NOTICE, "krb_rd_req: (%s)\n", krb_err_txt[kerror]); 131 dest_tkt(); 132 return(1); 133 } 134 /* failed for some other reason */ 135 (void)printf("unable to verify %s ticket: (%s)\n", VERIFY_SERVICE, 136 krb_err_txt[kerror]); 137 syslog(LOG_NOTICE, "couldn't verify %s ticket: %s", VERIFY_SERVICE, 138 krb_err_txt[kerror]); 139 dest_tkt(); 140 return(1); 141 } 142 #endif 143