diff options
Diffstat (limited to 'crypto/kerberosIV/appl/telnet/libtelnet/kerberos5.c')
-rw-r--r-- | crypto/kerberosIV/appl/telnet/libtelnet/kerberos5.c | 734 |
1 files changed, 734 insertions, 0 deletions
diff --git a/crypto/kerberosIV/appl/telnet/libtelnet/kerberos5.c b/crypto/kerberosIV/appl/telnet/libtelnet/kerberos5.c new file mode 100644 index 0000000..0b7818f --- /dev/null +++ b/crypto/kerberosIV/appl/telnet/libtelnet/kerberos5.c @@ -0,0 +1,734 @@ +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* + * Copyright (C) 1990 by the Massachusetts Institute of Technology + * + * Export of this software from the United States of America may + * require a specific license from the United States Government. + * It is the responsibility of any person or organization contemplating + * export to obtain such a license before exporting. + * + * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and + * distribute this software and its documentation for any purpose and + * without fee is hereby granted, provided that the above copyright + * notice appear in all copies and that both that copyright notice and + * this permission notice appear in supporting documentation, and that + * the name of M.I.T. not be used in advertising or publicity pertaining + * to distribution of the software without specific, written prior + * permission. M.I.T. makes no representations about the suitability of + * this software for any purpose. It is provided "as is" without express + * or implied warranty. + */ + +#include <config.h> + +RCSID("$Id: kerberos5.c,v 1.37 1999/06/24 17:09:10 assar Exp $"); + +#ifdef KRB5 + +#include <arpa/telnet.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <netdb.h> +#include <ctype.h> +#include <pwd.h> +#define Authenticator k5_Authenticator +#include <krb5.h> +#undef Authenticator +#include <roken.h> +#ifdef SOCKS +#include <socks.h> +#endif + + +#include "encrypt.h" +#include "auth.h" +#include "misc.h" + +int forward_flags = 0; /* Flags get set in telnet/main.c on -f and -F */ + +/* These values need to be the same as those defined in telnet/main.c. */ +/* Either define them in both places, or put in some common header file. */ +#define OPTS_FORWARD_CREDS 0x00000002 +#define OPTS_FORWARDABLE_CREDS 0x00000001 + +void kerberos5_forward (Authenticator *); + +static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0, + AUTHTYPE_KERBEROS_V5, }; + +#define KRB_AUTH 0 /* Authentication data follows */ +#define KRB_REJECT 1 /* Rejected (reason might follow) */ +#define KRB_ACCEPT 2 /* Accepted */ +#define KRB_RESPONSE 3 /* Response for mutual auth. */ + +#define KRB_FORWARD 4 /* Forwarded credentials follow */ +#define KRB_FORWARD_ACCEPT 5 /* Forwarded credentials accepted */ +#define KRB_FORWARD_REJECT 6 /* Forwarded credentials rejected */ + +static krb5_data auth; +static krb5_ticket *ticket; + +static krb5_context context; +static krb5_auth_context auth_context; + +static int +Data(Authenticator *ap, int type, void *d, int c) +{ + unsigned char *p = str_data + 4; + unsigned char *cd = (unsigned char *)d; + + if (c == -1) + c = strlen(cd); + + if (auth_debug_mode) { + printf("%s:%d: [%d] (%d)", + str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY", + str_data[3], + type, c); + printd(d, c); + printf("\r\n"); + } + *p++ = ap->type; + *p++ = ap->way; + *p++ = type; + while (c-- > 0) { + if ((*p++ = *cd++) == IAC) + *p++ = IAC; + } + *p++ = IAC; + *p++ = SE; + if (str_data[3] == TELQUAL_IS) + printsub('>', &str_data[2], p - &str_data[2]); + return(telnet_net_write(str_data, p - str_data)); +} + +int +kerberos5_init(Authenticator *ap, int server) +{ + if (server) + str_data[3] = TELQUAL_REPLY; + else + str_data[3] = TELQUAL_IS; + krb5_init_context(&context); + return(1); +} + +static int +kerberos5_send(char *name, Authenticator *ap) +{ + krb5_error_code ret; + krb5_ccache ccache; + int ap_opts; + krb5_data cksum_data; + char foo[2]; + extern int net; + + printf("[ Trying %s ... ]\r\n", name); + if (!UserNameRequested) { + if (auth_debug_mode) { + printf("Kerberos V5: no user name supplied\r\n"); + } + return(0); + } + + ret = krb5_cc_default(context, &ccache); + if (ret) { + if (auth_debug_mode) { + printf("Kerberos V5: could not get default ccache: %s\r\n", + krb5_get_err_text (context, ret)); + } + return 0; + } + + if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) + ap_opts = AP_OPTS_MUTUAL_REQUIRED; + else + ap_opts = 0; + + ret = krb5_auth_con_init (context, &auth_context); + if (ret) { + if (auth_debug_mode) { + printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n", + krb5_get_err_text(context, ret)); + } + return(0); + } + + ret = krb5_auth_con_setaddrs_from_fd (context, + auth_context, + &net); + if (ret) { + if (auth_debug_mode) { + printf ("Kerberos V5:" + " krb5_auth_con_setaddrs_from_fd failed (%s)\r\n", + krb5_get_err_text(context, ret)); + } + return(0); + } + + krb5_auth_setkeytype (context, auth_context, KEYTYPE_DES); + + foo[0] = ap->type; + foo[1] = ap->way; + + cksum_data.length = sizeof(foo); + cksum_data.data = foo; + ret = krb5_mk_req(context, &auth_context, ap_opts, + "host", RemoteHostName, + &cksum_data, ccache, &auth); + + if (ret) { + if (1 || auth_debug_mode) { + printf("Kerberos V5: mk_req failed (%s)\r\n", + krb5_get_err_text(context, ret)); + } + return(0); + } + + if (!auth_sendname((unsigned char *)UserNameRequested, + strlen(UserNameRequested))) { + if (auth_debug_mode) + printf("Not enough room for user name\r\n"); + return(0); + } + if (!Data(ap, KRB_AUTH, auth.data, auth.length)) { + if (auth_debug_mode) + printf("Not enough room for authentication data\r\n"); + return(0); + } + if (auth_debug_mode) { + printf("Sent Kerberos V5 credentials to server\r\n"); + } + return(1); +} + +int +kerberos5_send_mutual(Authenticator *ap) +{ + return kerberos5_send("mutual KERBEROS5", ap); +} + +int +kerberos5_send_oneway(Authenticator *ap) +{ + return kerberos5_send("KERBEROS5", ap); +} + +void +kerberos5_is(Authenticator *ap, unsigned char *data, int cnt) +{ + krb5_error_code ret; + krb5_data outbuf; + krb5_keyblock *key_block; + char *name; + krb5_principal server; + int zero = 0; + + if (cnt-- < 1) + return; + switch (*data++) { + case KRB_AUTH: + auth.data = (char *)data; + auth.length = cnt; + + auth_context = NULL; + + ret = krb5_auth_con_init (context, &auth_context); + if (ret) { + Data(ap, KRB_REJECT, "krb5_auth_con_init failed", -1); + auth_finished(ap, AUTH_REJECT); + if (auth_debug_mode) + printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n", + krb5_get_err_text(context, ret)); + return; + } + + ret = krb5_auth_con_setaddrs_from_fd (context, + auth_context, + &zero); + if (ret) { + Data(ap, KRB_REJECT, "krb5_auth_con_setaddrs_from_fd failed", -1); + auth_finished(ap, AUTH_REJECT); + if (auth_debug_mode) + printf("Kerberos V5: " + "krb5_auth_con_setaddrs_from_fd failed (%s)\r\n", + krb5_get_err_text(context, ret)); + return; + } + + ret = krb5_sock_to_principal (context, + 0, + "host", + KRB5_NT_SRV_HST, + &server); + if (ret) { + Data(ap, KRB_REJECT, "krb5_sock_to_principal failed", -1); + auth_finished(ap, AUTH_REJECT); + if (auth_debug_mode) + printf("Kerberos V5: " + "krb5_sock_to_principal failed (%s)\r\n", + krb5_get_err_text(context, ret)); + return; + } + + ret = krb5_rd_req(context, + &auth_context, + &auth, + server, + NULL, + NULL, + &ticket); + krb5_free_principal (context, server); + + if (ret) { + char *errbuf; + + asprintf(&errbuf, + "Read req failed: %s", + krb5_get_err_text(context, ret)); + Data(ap, KRB_REJECT, errbuf, -1); + if (auth_debug_mode) + printf("%s\r\n", errbuf); + free (errbuf); + return; + } + + { + char foo[2]; + + foo[0] = ap->type; + foo[1] = ap->way; + + ret = krb5_verify_authenticator_checksum(context, + auth_context, + foo, + sizeof(foo)); + + if (ret) { + char *errbuf; + asprintf(&errbuf, "Bad checksum: %s", + krb5_get_err_text(context, ret)); + Data(ap, KRB_REJECT, errbuf, -1); + if (auth_debug_mode) + printf ("%s\r\n", errbuf); + free(errbuf); + return; + } + } + ret = krb5_auth_con_getremotesubkey (context, + auth_context, + &key_block); + + if (ret) { + Data(ap, KRB_REJECT, "krb5_auth_con_getremotesubkey failed", -1); + auth_finished(ap, AUTH_REJECT); + if (auth_debug_mode) + printf("Kerberos V5: " + "krb5_auth_con_getremotesubkey failed (%s)\r\n", + krb5_get_err_text(context, ret)); + return; + } + + if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) { + ret = krb5_mk_rep(context, &auth_context, &outbuf); + if (ret) { + Data(ap, KRB_REJECT, + "krb5_mk_rep failed", -1); + auth_finished(ap, AUTH_REJECT); + if (auth_debug_mode) + printf("Kerberos V5: " + "krb5_mk_rep failed (%s)\r\n", + krb5_get_err_text(context, ret)); + return; + } + Data(ap, KRB_RESPONSE, outbuf.data, outbuf.length); + } + if (krb5_unparse_name(context, ticket->client, &name)) + name = 0; + + if(UserNameRequested && krb5_kuserok(context, + ticket->client, + UserNameRequested)) { + Data(ap, KRB_ACCEPT, name, name ? -1 : 0); + if (auth_debug_mode) { + printf("Kerberos5 identifies him as ``%s''\r\n", + name ? name : ""); + } + + if(key_block->keytype == ETYPE_DES_CBC_MD5 || + key_block->keytype == ETYPE_DES_CBC_MD4 || + key_block->keytype == ETYPE_DES_CBC_CRC) { + Session_Key skey; + + skey.type = SK_DES; + skey.length = 8; + skey.data = key_block->keyvalue.data; + encrypt_session_key(&skey, 0); + } + + } else { + char *msg; + + asprintf (&msg, "user `%s' is not authorized to " + "login as `%s'", + name ? name : "<unknown>", + UserNameRequested ? UserNameRequested : "<nobody>"); + if (msg == NULL) + Data(ap, KRB_REJECT, NULL, 0); + else { + Data(ap, KRB_REJECT, (void *)msg, -1); + free(msg); + } + } + auth_finished(ap, AUTH_USER); + + krb5_free_keyblock_contents(context, key_block); + + break; + case KRB_FORWARD: { + struct passwd *pwd; + char ccname[1024]; /* XXX */ + krb5_data inbuf; + krb5_ccache ccache; + inbuf.data = (char *)data; + inbuf.length = cnt; + + pwd = getpwnam (UserNameRequested); + if (pwd == NULL) + break; + + snprintf (ccname, sizeof(ccname), + "FILE:/tmp/krb5cc_%u", pwd->pw_uid); + + ret = krb5_cc_resolve (context, ccname, &ccache); + if (ret) { + if (auth_debug_mode) + printf ("Kerberos V5: could not get ccache: %s\r\n", + krb5_get_err_text(context, ret)); + break; + } + + ret = krb5_cc_initialize (context, + ccache, + ticket->client); + if (ret) { + if (auth_debug_mode) + printf ("Kerberos V5: could not init ccache: %s\r\n", + krb5_get_err_text(context, ret)); + break; + } + + ret = krb5_rd_cred (context, + auth_context, + ccache, + &inbuf); + if(ret) { + char *errbuf; + + asprintf (&errbuf, + "Read forwarded creds failed: %s", + krb5_get_err_text (context, ret)); + if(errbuf == NULL) + Data(ap, KRB_FORWARD_REJECT, NULL, 0); + else + Data(ap, KRB_FORWARD_REJECT, errbuf, -1); + if (auth_debug_mode) + printf("Could not read forwarded credentials: %s\r\n", + errbuf); + free (errbuf); + } else + Data(ap, KRB_FORWARD_ACCEPT, 0, 0); + chown (ccname + 5, pwd->pw_uid, -1); + if (auth_debug_mode) + printf("Forwarded credentials obtained\r\n"); + break; + } + default: + if (auth_debug_mode) + printf("Unknown Kerberos option %d\r\n", data[-1]); + Data(ap, KRB_REJECT, 0, 0); + break; + } +} + +void +kerberos5_reply(Authenticator *ap, unsigned char *data, int cnt) +{ + static int mutual_complete = 0; + + if (cnt-- < 1) + return; + switch (*data++) { + case KRB_REJECT: + if (cnt > 0) { + printf("[ Kerberos V5 refuses authentication because %.*s ]\r\n", + cnt, data); + } else + printf("[ Kerberos V5 refuses authentication ]\r\n"); + auth_send_retry(); + return; + case KRB_ACCEPT: { + krb5_error_code ret; + Session_Key skey; + krb5_keyblock *keyblock; + + if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL && + !mutual_complete) { + printf("[ Kerberos V5 accepted you, but didn't provide mutual authentication! ]\r\n"); + auth_send_retry(); + return; + } + if (cnt) + printf("[ Kerberos V5 accepts you as ``%.*s'' ]\r\n", cnt, data); + else + printf("[ Kerberos V5 accepts you ]\r\n"); + + ret = krb5_auth_con_getlocalsubkey (context, + auth_context, + &keyblock); + if (ret) + ret = krb5_auth_con_getkey (context, + auth_context, + &keyblock); + if(ret) { + printf("[ krb5_auth_con_getkey: %s ]\r\n", + krb5_get_err_text(context, ret)); + auth_send_retry(); + return; + } + + skey.type = SK_DES; + skey.length = 8; + skey.data = keyblock->keyvalue.data; + encrypt_session_key(&skey, 0); + krb5_free_keyblock_contents (context, keyblock); + auth_finished(ap, AUTH_USER); + if (forward_flags & OPTS_FORWARD_CREDS) + kerberos5_forward(ap); + break; + } + case KRB_RESPONSE: + if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) { + /* the rest of the reply should contain a krb_ap_rep */ + krb5_ap_rep_enc_part *reply; + krb5_data inbuf; + krb5_error_code ret; + + inbuf.length = cnt; + inbuf.data = (char *)data; + + ret = krb5_rd_rep(context, auth_context, &inbuf, &reply); + if (ret) { + printf("[ Mutual authentication failed: %s ]\r\n", + krb5_get_err_text (context, ret)); + auth_send_retry(); + return; + } + krb5_free_ap_rep_enc_part(context, reply); + mutual_complete = 1; + } + return; + case KRB_FORWARD_ACCEPT: + printf("[ Kerberos V5 accepted forwarded credentials ]\r\n"); + return; + case KRB_FORWARD_REJECT: + printf("[ Kerberos V5 refuses forwarded credentials because %.*s ]\r\n", + cnt, data); + return; + default: + if (auth_debug_mode) + printf("Unknown Kerberos option %d\r\n", data[-1]); + return; + } +} + +int +kerberos5_status(Authenticator *ap, char *name, size_t name_sz, int level) +{ + if (level < AUTH_USER) + return(level); + + if (UserNameRequested && + krb5_kuserok(context, + ticket->client, + UserNameRequested)) + { + strcpy_truncate(name, UserNameRequested, name_sz); + return(AUTH_VALID); + } else + return(AUTH_USER); +} + +#define BUMP(buf, len) while (*(buf)) {++(buf), --(len);} +#define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);} + +void +kerberos5_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen) +{ + int i; + + buf[buflen-1] = '\0'; /* make sure its NULL terminated */ + buflen -= 1; + + switch(data[3]) { + case KRB_REJECT: /* Rejected (reason might follow) */ + strcpy_truncate((char *)buf, " REJECT ", buflen); + goto common; + + case KRB_ACCEPT: /* Accepted (name might follow) */ + strcpy_truncate((char *)buf, " ACCEPT ", buflen); + common: + BUMP(buf, buflen); + if (cnt <= 4) + break; + ADDC(buf, buflen, '"'); + for (i = 4; i < cnt; i++) + ADDC(buf, buflen, data[i]); + ADDC(buf, buflen, '"'); + ADDC(buf, buflen, '\0'); + break; + + + case KRB_AUTH: /* Authentication data follows */ + strcpy_truncate((char *)buf, " AUTH", buflen); + goto common2; + + case KRB_RESPONSE: + strcpy_truncate((char *)buf, " RESPONSE", buflen); + goto common2; + + case KRB_FORWARD: /* Forwarded credentials follow */ + strcpy_truncate((char *)buf, " FORWARD", buflen); + goto common2; + + case KRB_FORWARD_ACCEPT: /* Forwarded credentials accepted */ + strcpy_truncate((char *)buf, " FORWARD_ACCEPT", buflen); + goto common2; + + case KRB_FORWARD_REJECT: /* Forwarded credentials rejected */ + /* (reason might follow) */ + strcpy_truncate((char *)buf, " FORWARD_REJECT", buflen); + goto common2; + + default: + snprintf(buf, buflen, " %d (unknown)", data[3]); + common2: + BUMP(buf, buflen); + for (i = 4; i < cnt; i++) { + snprintf(buf, buflen, " %d", data[i]); + BUMP(buf, buflen); + } + break; + } +} + +void +kerberos5_forward(Authenticator *ap) +{ + krb5_error_code ret; + krb5_ccache ccache; + krb5_creds creds; + krb5_kdc_flags flags; + krb5_data out_data; + krb5_principal principal; + + ret = krb5_cc_default (context, &ccache); + if (ret) { + if (auth_debug_mode) + printf ("KerberosV5: could not get default ccache: %s\r\n", + krb5_get_err_text (context, ret)); + return; + } + + ret = krb5_cc_get_principal (context, ccache, &principal); + if (ret) { + if (auth_debug_mode) + printf ("KerberosV5: could not get principal: %s\r\n", + krb5_get_err_text (context, ret)); + return; + } + + memset (&creds, 0, sizeof(creds)); + + creds.client = principal; + + ret = krb5_build_principal (context, + &creds.server, + strlen(principal->realm), + principal->realm, + "krbtgt", + principal->realm, + NULL); + + if (ret) { + if (auth_debug_mode) + printf ("KerberosV5: could not get principal: %s\r\n", + krb5_get_err_text (context, ret)); + return; + } + + creds.times.endtime = 0; + + flags.i = 0; + flags.b.forwarded = 1; + if (forward_flags & OPTS_FORWARDABLE_CREDS) + flags.b.forwardable = 1; + + ret = krb5_get_forwarded_creds (context, + auth_context, + ccache, + flags.i, + RemoteHostName, + &creds, + &out_data); + if (ret) { + if (auth_debug_mode) + printf ("Kerberos V5: error gettting forwarded creds: %s\r\n", + krb5_get_err_text (context, ret)); + return; + } + + if(!Data(ap, KRB_FORWARD, out_data.data, out_data.length)) { + if (auth_debug_mode) + printf("Not enough room for authentication data\r\n"); + } else { + if (auth_debug_mode) + printf("Forwarded local Kerberos V5 credentials to server\r\n"); + } +} + +#endif /* KRB5 */ |