| 1 | /*
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| 2 | Unix SMB/CIFS implementation.
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| 3 | kerberos utility library
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| 4 | Copyright (C) Andrew Tridgell 2001
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| 5 | Copyright (C) Remus Koos 2001
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| 6 | Copyright (C) Luke Howard 2003
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| 7 | Copyright (C) Guenther Deschner 2003, 2005
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| 8 | Copyright (C) Jim McDonough (jmcd@us.ibm.com) 2003
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| 9 | Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
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| 10 | Copyright (C) Jeremy Allison 2007
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| 11 |
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| 12 | This program is free software; you can redistribute it and/or modify
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| 13 | it under the terms of the GNU General Public License as published by
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| 14 | the Free Software Foundation; either version 3 of the License, or
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| 15 | (at your option) any later version.
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| 16 |
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| 17 | This program is distributed in the hope that it will be useful,
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| 18 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 19 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 20 | GNU General Public License for more details.
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| 21 |
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| 22 | You should have received a copy of the GNU General Public License
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| 23 | along with this program. If not, see <http://www.gnu.org/licenses/>.
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| 24 | */
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| 25 |
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| 26 | #include "includes.h"
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| 27 | #include "smb_krb5.h"
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| 28 |
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| 29 | #ifdef HAVE_KRB5
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| 30 |
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| 31 | #if !defined(HAVE_KRB5_PRINC_COMPONENT)
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| 32 | const krb5_data *krb5_princ_component(krb5_context, krb5_principal, int );
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| 33 | #endif
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| 34 |
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| 35 | static bool ads_dedicated_keytab_verify_ticket(krb5_context context,
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| 36 | krb5_auth_context auth_context,
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| 37 | const DATA_BLOB *ticket,
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| 38 | krb5_ticket **pp_tkt,
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| 39 | krb5_keyblock **keyblock,
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| 40 | krb5_error_code *perr)
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| 41 | {
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| 42 | krb5_error_code ret = 0;
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| 43 | bool auth_ok = false;
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| 44 | krb5_keytab keytab = NULL;
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| 45 | krb5_keytab_entry kt_entry;
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| 46 | krb5_ticket *dec_ticket = NULL;
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| 47 |
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| 48 | krb5_data packet;
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| 49 | krb5_kvno kvno = 0;
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| 50 | krb5_enctype enctype;
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| 51 |
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| 52 | *pp_tkt = NULL;
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| 53 | *keyblock = NULL;
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| 54 | *perr = 0;
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| 55 |
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| 56 | ZERO_STRUCT(kt_entry);
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| 57 |
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| 58 | ret = smb_krb5_open_keytab(context, lp_dedicated_keytab_file(), true,
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| 59 | &keytab);
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| 60 | if (ret) {
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| 61 | DEBUG(1, ("smb_krb5_open_keytab failed (%s)\n",
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| 62 | error_message(ret)));
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| 63 | goto out;
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| 64 | }
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| 65 |
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| 66 | packet.length = ticket->length;
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| 67 | packet.data = (char *)ticket->data;
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| 68 |
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| 69 | ret = krb5_rd_req(context, &auth_context, &packet, NULL, keytab,
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| 70 | NULL, &dec_ticket);
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| 71 | if (ret) {
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| 72 | DEBUG(0, ("krb5_rd_req failed (%s)\n", error_message(ret)));
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| 73 | goto out;
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| 74 | }
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| 75 |
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| 76 | #ifdef HAVE_ETYPE_IN_ENCRYPTEDDATA /* Heimdal */
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| 77 | enctype = dec_ticket->ticket.key.keytype;
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| 78 | #else /* MIT */
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| 79 | enctype = dec_ticket->enc_part.enctype;
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| 80 | kvno = dec_ticket->enc_part.kvno;
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| 81 | #endif
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| 82 |
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| 83 | /* Get the key for checking the pac signature */
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| 84 | ret = krb5_kt_get_entry(context, keytab, dec_ticket->server,
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| 85 | kvno, enctype, &kt_entry);
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| 86 | if (ret) {
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| 87 | DEBUG(0, ("krb5_kt_get_entry failed (%s)\n",
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| 88 | error_message(ret)));
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| 89 | goto out;
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| 90 | }
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| 91 |
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| 92 | ret = krb5_copy_keyblock(context, KRB5_KT_KEY(&kt_entry), keyblock);
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| 93 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 94 |
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| 95 | if (ret) {
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| 96 | DEBUG(0, ("failed to copy key: %s\n",
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| 97 | error_message(ret)));
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| 98 | goto out;
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| 99 | }
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| 100 |
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| 101 | auth_ok = true;
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| 102 | *pp_tkt = dec_ticket;
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| 103 | dec_ticket = NULL;
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| 104 |
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| 105 | out:
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| 106 | if (dec_ticket)
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| 107 | krb5_free_ticket(context, dec_ticket);
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| 108 |
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| 109 | if (keytab)
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| 110 | krb5_kt_close(context, keytab);
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| 111 |
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| 112 | *perr = ret;
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| 113 | return auth_ok;
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| 114 | }
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| 115 |
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| 116 | /**********************************************************************************
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| 117 | Try to verify a ticket using the system keytab... the system keytab has kvno -1 entries, so
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| 118 | it's more like what microsoft does... see comment in utils/net_ads.c in the
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| 119 | ads_keytab_add_entry function for details.
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| 120 | ***********************************************************************************/
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| 121 |
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| 122 | static bool ads_keytab_verify_ticket(krb5_context context,
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| 123 | krb5_auth_context auth_context,
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| 124 | const DATA_BLOB *ticket,
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| 125 | krb5_ticket **pp_tkt,
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| 126 | krb5_keyblock **keyblock,
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| 127 | krb5_error_code *perr)
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| 128 | {
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| 129 | krb5_error_code ret = 0;
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| 130 | bool auth_ok = False;
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| 131 | krb5_keytab keytab = NULL;
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| 132 | krb5_kt_cursor kt_cursor;
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| 133 | krb5_keytab_entry kt_entry;
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| 134 | char *valid_princ_formats[7] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL };
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| 135 | char *entry_princ_s = NULL;
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| 136 | fstring my_name, my_fqdn;
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| 137 | int i;
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| 138 | int number_matched_principals = 0;
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| 139 | krb5_data packet;
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| 140 |
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| 141 | *pp_tkt = NULL;
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| 142 | *keyblock = NULL;
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| 143 | *perr = 0;
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| 144 |
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| 145 | /* Generate the list of principal names which we expect
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| 146 | * clients might want to use for authenticating to the file
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| 147 | * service. We allow name$,{host,cifs}/{name,fqdn,name.REALM}. */
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| 148 |
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| 149 | fstrcpy(my_name, global_myname());
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| 150 |
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| 151 | my_fqdn[0] = '\0';
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| 152 | name_to_fqdn(my_fqdn, global_myname());
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| 153 |
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| 154 | if (asprintf(&valid_princ_formats[0], "%s$@%s", my_name, lp_realm()) == -1) {
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| 155 | goto out;
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| 156 | }
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| 157 | if (asprintf(&valid_princ_formats[1], "host/%s@%s", my_name, lp_realm()) == -1) {
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| 158 | goto out;
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| 159 | }
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| 160 | if (asprintf(&valid_princ_formats[2], "host/%s@%s", my_fqdn, lp_realm()) == -1) {
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| 161 | goto out;
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| 162 | }
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| 163 | if (asprintf(&valid_princ_formats[3], "host/%s.%s@%s", my_name, lp_realm(), lp_realm()) == -1) {
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| 164 | goto out;
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| 165 | }
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| 166 | if (asprintf(&valid_princ_formats[4], "cifs/%s@%s", my_name, lp_realm()) == -1) {
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| 167 | goto out;
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| 168 | }
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| 169 | if (asprintf(&valid_princ_formats[5], "cifs/%s@%s", my_fqdn, lp_realm()) == -1) {
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| 170 | goto out;
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| 171 | }
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| 172 | if (asprintf(&valid_princ_formats[6], "cifs/%s.%s@%s", my_name, lp_realm(), lp_realm()) == -1) {
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| 173 | goto out;
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| 174 | }
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| 175 |
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| 176 | ZERO_STRUCT(kt_entry);
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| 177 | ZERO_STRUCT(kt_cursor);
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| 178 |
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| 179 | ret = smb_krb5_open_keytab(context, NULL, False, &keytab);
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| 180 | if (ret) {
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| 181 | DEBUG(1, ("ads_keytab_verify_ticket: smb_krb5_open_keytab failed (%s)\n", error_message(ret)));
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| 182 | goto out;
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| 183 | }
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| 184 |
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| 185 | /* Iterate through the keytab. For each key, if the principal
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| 186 | * name case-insensitively matches one of the allowed formats,
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| 187 | * try verifying the ticket using that principal. */
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| 188 |
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| 189 | ret = krb5_kt_start_seq_get(context, keytab, &kt_cursor);
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| 190 | if (ret) {
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| 191 | DEBUG(1, ("ads_keytab_verify_ticket: krb5_kt_start_seq_get failed (%s)\n", error_message(ret)));
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| 192 | goto out;
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| 193 | }
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| 194 |
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| 195 | while (!auth_ok && (krb5_kt_next_entry(context, keytab, &kt_entry, &kt_cursor) == 0)) {
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| 196 | ret = smb_krb5_unparse_name(talloc_tos(), context, kt_entry.principal, &entry_princ_s);
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| 197 | if (ret) {
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| 198 | DEBUG(1, ("ads_keytab_verify_ticket: smb_krb5_unparse_name failed (%s)\n",
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| 199 | error_message(ret)));
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| 200 | goto out;
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| 201 | }
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| 202 |
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| 203 | for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
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| 204 |
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| 205 | if (!strequal(entry_princ_s, valid_princ_formats[i])) {
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| 206 | continue;
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| 207 | }
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| 208 |
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| 209 | number_matched_principals++;
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| 210 | packet.length = ticket->length;
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| 211 | packet.data = (char *)ticket->data;
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| 212 | *pp_tkt = NULL;
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| 213 |
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| 214 | ret = krb5_rd_req_return_keyblock_from_keytab(context, &auth_context, &packet,
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| 215 | kt_entry.principal, keytab,
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| 216 | NULL, pp_tkt, keyblock);
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| 217 |
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| 218 | if (ret) {
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| 219 | DEBUG(10,("ads_keytab_verify_ticket: "
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| 220 | "krb5_rd_req_return_keyblock_from_keytab(%s) failed: %s\n",
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| 221 | entry_princ_s, error_message(ret)));
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| 222 |
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| 223 | /* workaround for MIT:
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| 224 | * as krb5_ktfile_get_entry will explicitly
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| 225 | * close the krb5_keytab as soon as krb5_rd_req
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| 226 | * has successfully decrypted the ticket but the
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| 227 | * ticket is not valid yet (due to clockskew)
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| 228 | * there is no point in querying more keytab
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| 229 | * entries - Guenther */
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| 230 |
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| 231 | if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
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| 232 | ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
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| 233 | ret == KRB5KRB_AP_ERR_SKEW) {
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| 234 | break;
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| 235 | }
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| 236 | } else {
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| 237 | DEBUG(3,("ads_keytab_verify_ticket: "
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| 238 | "krb5_rd_req_return_keyblock_from_keytab succeeded for principal %s\n",
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| 239 | entry_princ_s));
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| 240 | auth_ok = True;
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| 241 | break;
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| 242 | }
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| 243 | }
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| 244 |
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| 245 | /* Free the name we parsed. */
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| 246 | TALLOC_FREE(entry_princ_s);
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| 247 |
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| 248 | /* Free the entry we just read. */
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| 249 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 250 | ZERO_STRUCT(kt_entry);
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| 251 | }
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| 252 | krb5_kt_end_seq_get(context, keytab, &kt_cursor);
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| 253 |
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| 254 | ZERO_STRUCT(kt_cursor);
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| 255 |
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| 256 | out:
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| 257 |
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| 258 | for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
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| 259 | SAFE_FREE(valid_princ_formats[i]);
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| 260 | }
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| 261 |
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| 262 | if (!auth_ok) {
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| 263 | if (!number_matched_principals) {
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| 264 | DEBUG(3, ("ads_keytab_verify_ticket: no keytab principals matched expected file service name.\n"));
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| 265 | } else {
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| 266 | DEBUG(3, ("ads_keytab_verify_ticket: krb5_rd_req failed for all %d matched keytab principals\n",
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| 267 | number_matched_principals));
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| 268 | }
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| 269 | }
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| 270 |
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| 271 | SAFE_FREE(entry_princ_s);
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| 272 |
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| 273 | {
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| 274 | krb5_keytab_entry zero_kt_entry;
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| 275 | ZERO_STRUCT(zero_kt_entry);
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| 276 | if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
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| 277 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 278 | }
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| 279 | }
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| 280 |
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| 281 | {
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| 282 | krb5_kt_cursor zero_csr;
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| 283 | ZERO_STRUCT(zero_csr);
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| 284 | if ((memcmp(&kt_cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) && keytab) {
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| 285 | krb5_kt_end_seq_get(context, keytab, &kt_cursor);
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| 286 | }
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| 287 | }
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| 288 |
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| 289 | if (keytab) {
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| 290 | krb5_kt_close(context, keytab);
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| 291 | }
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| 292 | *perr = ret;
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| 293 | return auth_ok;
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| 294 | }
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| 295 |
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| 296 | /**********************************************************************************
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| 297 | Try to verify a ticket using the secrets.tdb.
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| 298 | ***********************************************************************************/
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| 299 |
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| 300 | static krb5_error_code ads_secrets_verify_ticket(krb5_context context,
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| 301 | krb5_auth_context auth_context,
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| 302 | krb5_principal host_princ,
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| 303 | const DATA_BLOB *ticket,
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| 304 | krb5_ticket **pp_tkt,
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| 305 | krb5_keyblock **keyblock,
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| 306 | krb5_error_code *perr)
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| 307 | {
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| 308 | krb5_error_code ret = 0;
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| 309 | bool auth_ok = False;
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| 310 | bool cont = true;
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| 311 | char *password_s = NULL;
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| 312 | /* Let's make some room for 2 password (old and new)*/
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| 313 | krb5_data passwords[2];
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| 314 | krb5_enctype enctypes[] = {
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| 315 | #if defined(ENCTYPE_ARCFOUR_HMAC)
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| 316 | ENCTYPE_ARCFOUR_HMAC,
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| 317 | #endif
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| 318 | ENCTYPE_DES_CBC_CRC,
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| 319 | ENCTYPE_DES_CBC_MD5,
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| 320 | ENCTYPE_NULL
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| 321 | };
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| 322 | krb5_data packet;
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| 323 | int i, j;
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| 324 |
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| 325 | *pp_tkt = NULL;
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| 326 | *keyblock = NULL;
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| 327 | *perr = 0;
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| 328 |
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| 329 | ZERO_STRUCT(passwords);
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| 330 |
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| 331 | if (!secrets_init()) {
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| 332 | DEBUG(1,("ads_secrets_verify_ticket: secrets_init failed\n"));
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| 333 | *perr = KRB5_CONFIG_CANTOPEN;
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| 334 | return False;
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| 335 | }
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| 336 |
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| 337 | password_s = secrets_fetch_machine_password(lp_workgroup(), NULL, NULL);
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| 338 | if (!password_s) {
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| 339 | DEBUG(1,("ads_secrets_verify_ticket: failed to fetch machine password\n"));
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| 340 | *perr = KRB5_LIBOS_CANTREADPWD;
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| 341 | return False;
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| 342 | }
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| 343 |
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| 344 | passwords[0].data = password_s;
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| 345 | passwords[0].length = strlen(password_s);
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| 346 |
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| 347 | password_s = secrets_fetch_prev_machine_password(lp_workgroup());
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| 348 | if (password_s) {
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| 349 | DEBUG(10,("ads_secrets_verify_ticket: found previous password\n"));
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| 350 | passwords[1].data = password_s;
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| 351 | passwords[1].length = strlen(password_s);
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| 352 | }
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| 353 |
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| 354 | /* CIFS doesn't use addresses in tickets. This would break NAT. JRA */
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| 355 |
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| 356 | packet.length = ticket->length;
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| 357 | packet.data = (char *)ticket->data;
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| 358 |
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| 359 | /* We need to setup a auth context with each possible encoding type in turn. */
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| 360 | for (j=0; j<2 && passwords[j].length; j++) {
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| 361 |
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| 362 | for (i=0;enctypes[i];i++) {
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| 363 | krb5_keyblock *key = NULL;
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| 364 |
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| 365 | if (!(key = SMB_MALLOC_P(krb5_keyblock))) {
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| 366 | ret = ENOMEM;
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| 367 | goto out;
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| 368 | }
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| 369 |
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| 370 | if (create_kerberos_key_from_string(context, host_princ, &passwords[j], key, enctypes[i], false)) {
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| 371 | SAFE_FREE(key);
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| 372 | continue;
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| 373 | }
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| 374 |
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| 375 | krb5_auth_con_setuseruserkey(context, auth_context, key);
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| 376 |
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| 377 | if (!(ret = krb5_rd_req(context, &auth_context, &packet,
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| 378 | NULL,
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| 379 | NULL, NULL, pp_tkt))) {
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| 380 | DEBUG(10,("ads_secrets_verify_ticket: enc type [%u] decrypted message !\n",
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| 381 | (unsigned int)enctypes[i] ));
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| 382 | auth_ok = True;
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| 383 | cont = false;
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| 384 | krb5_copy_keyblock(context, key, keyblock);
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| 385 | krb5_free_keyblock(context, key);
|
|---|
| 386 | break;
|
|---|
| 387 | }
|
|---|
| 388 |
|
|---|
| 389 | DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
|
|---|
| 390 | ("ads_secrets_verify_ticket: enc type [%u] failed to decrypt with error %s\n",
|
|---|
| 391 | (unsigned int)enctypes[i], error_message(ret)));
|
|---|
| 392 |
|
|---|
| 393 | /* successfully decrypted but ticket is just not valid at the moment */
|
|---|
| 394 | if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
|
|---|
| 395 | ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
|
|---|
| 396 | ret == KRB5KRB_AP_ERR_SKEW) {
|
|---|
| 397 | krb5_free_keyblock(context, key);
|
|---|
| 398 | cont = false;
|
|---|
| 399 | break;
|
|---|
| 400 | }
|
|---|
| 401 |
|
|---|
| 402 | krb5_free_keyblock(context, key);
|
|---|
| 403 | }
|
|---|
| 404 | if (!cont) {
|
|---|
| 405 | /* If we found a valid pass then no need to try
|
|---|
| 406 | * the next one or we have invalid ticket so no need
|
|---|
| 407 | * to try next password*/
|
|---|
| 408 | break;
|
|---|
| 409 | }
|
|---|
| 410 | }
|
|---|
| 411 |
|
|---|
| 412 | out:
|
|---|
| 413 | SAFE_FREE(passwords[0].data);
|
|---|
| 414 | SAFE_FREE(passwords[1].data);
|
|---|
| 415 | *perr = ret;
|
|---|
| 416 | return auth_ok;
|
|---|
| 417 | }
|
|---|
| 418 |
|
|---|
| 419 | /**********************************************************************************
|
|---|
| 420 | Verify an incoming ticket and parse out the principal name and
|
|---|
| 421 | authorization_data if available.
|
|---|
| 422 | ***********************************************************************************/
|
|---|
| 423 |
|
|---|
| 424 | NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
|
|---|
| 425 | const char *realm,
|
|---|
| 426 | time_t time_offset,
|
|---|
| 427 | const DATA_BLOB *ticket,
|
|---|
| 428 | char **principal,
|
|---|
| 429 | struct PAC_DATA **pac_data,
|
|---|
| 430 | DATA_BLOB *ap_rep,
|
|---|
| 431 | DATA_BLOB *session_key,
|
|---|
| 432 | bool use_replay_cache)
|
|---|
| 433 | {
|
|---|
| 434 | NTSTATUS sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 435 | NTSTATUS pac_ret;
|
|---|
| 436 | DATA_BLOB auth_data;
|
|---|
| 437 | krb5_context context = NULL;
|
|---|
| 438 | krb5_auth_context auth_context = NULL;
|
|---|
| 439 | krb5_data packet;
|
|---|
| 440 | krb5_ticket *tkt = NULL;
|
|---|
| 441 | krb5_rcache rcache = NULL;
|
|---|
| 442 | krb5_keyblock *keyblock = NULL;
|
|---|
| 443 | time_t authtime;
|
|---|
| 444 | krb5_error_code ret = 0;
|
|---|
| 445 | int flags = 0;
|
|---|
| 446 | krb5_principal host_princ = NULL;
|
|---|
| 447 | krb5_const_principal client_principal = NULL;
|
|---|
| 448 | char *host_princ_s = NULL;
|
|---|
| 449 | bool auth_ok = False;
|
|---|
| 450 | bool got_auth_data = False;
|
|---|
| 451 | struct named_mutex *mutex = NULL;
|
|---|
| 452 |
|
|---|
| 453 | ZERO_STRUCT(packet);
|
|---|
| 454 | ZERO_STRUCT(auth_data);
|
|---|
| 455 |
|
|---|
| 456 | *principal = NULL;
|
|---|
| 457 | *pac_data = NULL;
|
|---|
| 458 | *ap_rep = data_blob_null;
|
|---|
| 459 | *session_key = data_blob_null;
|
|---|
| 460 |
|
|---|
| 461 | initialize_krb5_error_table();
|
|---|
| 462 | ret = krb5_init_context(&context);
|
|---|
| 463 | if (ret) {
|
|---|
| 464 | DEBUG(1,("ads_verify_ticket: krb5_init_context failed (%s)\n", error_message(ret)));
|
|---|
| 465 | return NT_STATUS_LOGON_FAILURE;
|
|---|
| 466 | }
|
|---|
| 467 |
|
|---|
| 468 | if (time_offset != 0) {
|
|---|
| 469 | krb5_set_real_time(context, time(NULL) + time_offset, 0);
|
|---|
| 470 | }
|
|---|
| 471 |
|
|---|
| 472 | ret = krb5_set_default_realm(context, realm);
|
|---|
| 473 | if (ret) {
|
|---|
| 474 | DEBUG(1,("ads_verify_ticket: krb5_set_default_realm failed (%s)\n", error_message(ret)));
|
|---|
| 475 | goto out;
|
|---|
| 476 | }
|
|---|
| 477 |
|
|---|
| 478 | /* This whole process is far more complex than I would
|
|---|
| 479 | like. We have to go through all this to allow us to store
|
|---|
| 480 | the secret internally, instead of using /etc/krb5.keytab */
|
|---|
| 481 |
|
|---|
| 482 | ret = krb5_auth_con_init(context, &auth_context);
|
|---|
| 483 | if (ret) {
|
|---|
| 484 | DEBUG(1,("ads_verify_ticket: krb5_auth_con_init failed (%s)\n", error_message(ret)));
|
|---|
| 485 | goto out;
|
|---|
| 486 | }
|
|---|
| 487 |
|
|---|
| 488 | krb5_auth_con_getflags( context, auth_context, &flags );
|
|---|
| 489 | if ( !use_replay_cache ) {
|
|---|
| 490 | /* Disable default use of a replay cache */
|
|---|
| 491 | flags &= ~KRB5_AUTH_CONTEXT_DO_TIME;
|
|---|
| 492 | krb5_auth_con_setflags( context, auth_context, flags );
|
|---|
| 493 | }
|
|---|
| 494 |
|
|---|
| 495 | if (asprintf(&host_princ_s, "%s$", global_myname()) == -1) {
|
|---|
| 496 | goto out;
|
|---|
| 497 | }
|
|---|
| 498 |
|
|---|
| 499 | strlower_m(host_princ_s);
|
|---|
| 500 | ret = smb_krb5_parse_name(context, host_princ_s, &host_princ);
|
|---|
| 501 | if (ret) {
|
|---|
| 502 | DEBUG(1,("ads_verify_ticket: smb_krb5_parse_name(%s) failed (%s)\n",
|
|---|
| 503 | host_princ_s, error_message(ret)));
|
|---|
| 504 | goto out;
|
|---|
| 505 | }
|
|---|
| 506 |
|
|---|
| 507 |
|
|---|
| 508 | if ( use_replay_cache ) {
|
|---|
| 509 |
|
|---|
| 510 | /* Lock a mutex surrounding the replay as there is no
|
|---|
| 511 | locking in the MIT krb5 code surrounding the replay
|
|---|
| 512 | cache... */
|
|---|
| 513 |
|
|---|
| 514 | mutex = grab_named_mutex(talloc_tos(), "replay cache mutex",
|
|---|
| 515 | 10);
|
|---|
| 516 | if (mutex == NULL) {
|
|---|
| 517 | DEBUG(1,("ads_verify_ticket: unable to protect "
|
|---|
| 518 | "replay cache with mutex.\n"));
|
|---|
| 519 | ret = KRB5_CC_IO;
|
|---|
| 520 | goto out;
|
|---|
| 521 | }
|
|---|
| 522 |
|
|---|
| 523 | /* JRA. We must set the rcache here. This will prevent
|
|---|
| 524 | replay attacks. */
|
|---|
| 525 |
|
|---|
| 526 | ret = krb5_get_server_rcache(context,
|
|---|
| 527 | krb5_princ_component(context, host_princ, 0),
|
|---|
| 528 | &rcache);
|
|---|
| 529 | if (ret) {
|
|---|
| 530 | DEBUG(1,("ads_verify_ticket: krb5_get_server_rcache "
|
|---|
| 531 | "failed (%s)\n", error_message(ret)));
|
|---|
| 532 | goto out;
|
|---|
| 533 | }
|
|---|
| 534 |
|
|---|
| 535 | ret = krb5_auth_con_setrcache(context, auth_context, rcache);
|
|---|
| 536 | if (ret) {
|
|---|
| 537 | DEBUG(1,("ads_verify_ticket: krb5_auth_con_setrcache "
|
|---|
| 538 | "failed (%s)\n", error_message(ret)));
|
|---|
| 539 | goto out;
|
|---|
| 540 | }
|
|---|
| 541 | }
|
|---|
| 542 |
|
|---|
| 543 | switch (lp_kerberos_method()) {
|
|---|
| 544 | default:
|
|---|
| 545 | case KERBEROS_VERIFY_SECRETS:
|
|---|
| 546 | auth_ok = ads_secrets_verify_ticket(context, auth_context,
|
|---|
| 547 | host_princ, ticket, &tkt, &keyblock, &ret);
|
|---|
| 548 | break;
|
|---|
| 549 | case KERBEROS_VERIFY_SYSTEM_KEYTAB:
|
|---|
| 550 | auth_ok = ads_keytab_verify_ticket(context, auth_context,
|
|---|
| 551 | ticket, &tkt, &keyblock, &ret);
|
|---|
| 552 | break;
|
|---|
| 553 | case KERBEROS_VERIFY_DEDICATED_KEYTAB:
|
|---|
| 554 | auth_ok = ads_dedicated_keytab_verify_ticket(context,
|
|---|
| 555 | auth_context, ticket, &tkt, &keyblock, &ret);
|
|---|
| 556 | break;
|
|---|
| 557 | case KERBEROS_VERIFY_SECRETS_AND_KEYTAB:
|
|---|
| 558 | /* First try secrets.tdb and fallback to the krb5.keytab if
|
|---|
| 559 | necessary. This is the pre 3.4 behavior when
|
|---|
| 560 | "use kerberos keytab" was true.*/
|
|---|
| 561 | auth_ok = ads_secrets_verify_ticket(context, auth_context,
|
|---|
| 562 | host_princ, ticket, &tkt, &keyblock, &ret);
|
|---|
| 563 |
|
|---|
| 564 | if (!auth_ok) {
|
|---|
| 565 | /* Only fallback if we failed to decrypt the ticket */
|
|---|
| 566 | if (ret != KRB5KRB_AP_ERR_TKT_NYV &&
|
|---|
| 567 | ret != KRB5KRB_AP_ERR_TKT_EXPIRED &&
|
|---|
| 568 | ret != KRB5KRB_AP_ERR_SKEW) {
|
|---|
| 569 | auth_ok = ads_keytab_verify_ticket(context,
|
|---|
| 570 | auth_context, ticket, &tkt, &keyblock,
|
|---|
| 571 | &ret);
|
|---|
| 572 | }
|
|---|
| 573 | }
|
|---|
| 574 | break;
|
|---|
| 575 | }
|
|---|
| 576 |
|
|---|
| 577 | if ( use_replay_cache ) {
|
|---|
| 578 | TALLOC_FREE(mutex);
|
|---|
| 579 | #if 0
|
|---|
| 580 | /* Heimdal leaks here, if we fix the leak, MIT crashes */
|
|---|
| 581 | if (rcache) {
|
|---|
| 582 | krb5_rc_close(context, rcache);
|
|---|
| 583 | }
|
|---|
| 584 | #endif
|
|---|
| 585 | }
|
|---|
| 586 |
|
|---|
| 587 | if (!auth_ok) {
|
|---|
| 588 | DEBUG(3,("ads_verify_ticket: krb5_rd_req with auth failed (%s)\n",
|
|---|
| 589 | error_message(ret)));
|
|---|
| 590 | /* Try map the error return in case it's something like
|
|---|
| 591 | * a clock skew error.
|
|---|
| 592 | */
|
|---|
| 593 | sret = krb5_to_nt_status(ret);
|
|---|
| 594 | if (NT_STATUS_IS_OK(sret) || NT_STATUS_EQUAL(sret,NT_STATUS_UNSUCCESSFUL)) {
|
|---|
| 595 | sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 596 | }
|
|---|
| 597 | DEBUG(10,("ads_verify_ticket: returning error %s\n",
|
|---|
| 598 | nt_errstr(sret) ));
|
|---|
| 599 | goto out;
|
|---|
| 600 | }
|
|---|
| 601 |
|
|---|
| 602 | authtime = get_authtime_from_tkt(tkt);
|
|---|
| 603 | client_principal = get_principal_from_tkt(tkt);
|
|---|
| 604 |
|
|---|
| 605 | ret = krb5_mk_rep(context, auth_context, &packet);
|
|---|
| 606 | if (ret) {
|
|---|
| 607 | DEBUG(3,("ads_verify_ticket: Failed to generate mutual authentication reply (%s)\n",
|
|---|
| 608 | error_message(ret)));
|
|---|
| 609 | goto out;
|
|---|
| 610 | }
|
|---|
| 611 |
|
|---|
| 612 | *ap_rep = data_blob(packet.data, packet.length);
|
|---|
| 613 | if (packet.data) {
|
|---|
| 614 | kerberos_free_data_contents(context, &packet);
|
|---|
| 615 | ZERO_STRUCT(packet);
|
|---|
| 616 | }
|
|---|
| 617 |
|
|---|
| 618 | get_krb5_smb_session_key(context, auth_context, session_key, True);
|
|---|
| 619 | dump_data_pw("SMB session key (from ticket)\n", session_key->data, session_key->length);
|
|---|
| 620 |
|
|---|
| 621 | #if 0
|
|---|
| 622 | file_save("/tmp/ticket.dat", ticket->data, ticket->length);
|
|---|
| 623 | #endif
|
|---|
| 624 |
|
|---|
| 625 | /* continue when no PAC is retrieved or we couldn't decode the PAC
|
|---|
| 626 | (like accounts that have the UF_NO_AUTH_DATA_REQUIRED flag set, or
|
|---|
| 627 | Kerberos tickets encrypted using a DES key) - Guenther */
|
|---|
| 628 |
|
|---|
| 629 | got_auth_data = get_auth_data_from_tkt(mem_ctx, &auth_data, tkt);
|
|---|
| 630 | if (!got_auth_data) {
|
|---|
| 631 | DEBUG(3,("ads_verify_ticket: did not retrieve auth data. continuing without PAC\n"));
|
|---|
| 632 | }
|
|---|
| 633 |
|
|---|
| 634 | if (got_auth_data) {
|
|---|
| 635 | pac_ret = decode_pac_data(mem_ctx, &auth_data, context, keyblock, client_principal, authtime, pac_data);
|
|---|
| 636 | if (!NT_STATUS_IS_OK(pac_ret)) {
|
|---|
| 637 | DEBUG(3,("ads_verify_ticket: failed to decode PAC_DATA: %s\n", nt_errstr(pac_ret)));
|
|---|
| 638 | *pac_data = NULL;
|
|---|
| 639 | }
|
|---|
| 640 | data_blob_free(&auth_data);
|
|---|
| 641 | }
|
|---|
| 642 |
|
|---|
| 643 | #if 0
|
|---|
| 644 | #if defined(HAVE_KRB5_TKT_ENC_PART2)
|
|---|
| 645 | /* MIT */
|
|---|
| 646 | if (tkt->enc_part2) {
|
|---|
| 647 | file_save("/tmp/authdata.dat",
|
|---|
| 648 | tkt->enc_part2->authorization_data[0]->contents,
|
|---|
| 649 | tkt->enc_part2->authorization_data[0]->length);
|
|---|
| 650 | }
|
|---|
| 651 | #else
|
|---|
| 652 | /* Heimdal */
|
|---|
| 653 | if (tkt->ticket.authorization_data) {
|
|---|
| 654 | file_save("/tmp/authdata.dat",
|
|---|
| 655 | tkt->ticket.authorization_data->val->ad_data.data,
|
|---|
| 656 | tkt->ticket.authorization_data->val->ad_data.length);
|
|---|
| 657 | }
|
|---|
| 658 | #endif
|
|---|
| 659 | #endif
|
|---|
| 660 |
|
|---|
| 661 | if ((ret = smb_krb5_unparse_name(mem_ctx, context, client_principal, principal))) {
|
|---|
| 662 | DEBUG(3,("ads_verify_ticket: smb_krb5_unparse_name failed (%s)\n",
|
|---|
| 663 | error_message(ret)));
|
|---|
| 664 | sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 665 | goto out;
|
|---|
| 666 | }
|
|---|
| 667 |
|
|---|
| 668 | sret = NT_STATUS_OK;
|
|---|
| 669 |
|
|---|
| 670 | out:
|
|---|
| 671 |
|
|---|
| 672 | TALLOC_FREE(mutex);
|
|---|
| 673 |
|
|---|
| 674 | if (!NT_STATUS_IS_OK(sret)) {
|
|---|
| 675 | data_blob_free(&auth_data);
|
|---|
| 676 | }
|
|---|
| 677 |
|
|---|
| 678 | if (!NT_STATUS_IS_OK(sret)) {
|
|---|
| 679 | data_blob_free(ap_rep);
|
|---|
| 680 | }
|
|---|
| 681 |
|
|---|
| 682 | if (host_princ) {
|
|---|
| 683 | krb5_free_principal(context, host_princ);
|
|---|
| 684 | }
|
|---|
| 685 |
|
|---|
| 686 | if (keyblock) {
|
|---|
| 687 | krb5_free_keyblock(context, keyblock);
|
|---|
| 688 | }
|
|---|
| 689 |
|
|---|
| 690 | if (tkt != NULL) {
|
|---|
| 691 | krb5_free_ticket(context, tkt);
|
|---|
| 692 | }
|
|---|
| 693 |
|
|---|
| 694 | SAFE_FREE(host_princ_s);
|
|---|
| 695 |
|
|---|
| 696 | if (auth_context) {
|
|---|
| 697 | krb5_auth_con_free(context, auth_context);
|
|---|
| 698 | }
|
|---|
| 699 |
|
|---|
| 700 | if (context) {
|
|---|
| 701 | krb5_free_context(context);
|
|---|
| 702 | }
|
|---|
| 703 |
|
|---|
| 704 | return sret;
|
|---|
| 705 | }
|
|---|
| 706 |
|
|---|
| 707 | #endif /* HAVE_KRB5 */
|
|---|