| 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 | #include "libads/kerberos_proto.h"
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| 29 | #include "secrets.h"
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| 30 | #include "../librpc/gen_ndr/krb5pac.h"
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| 31 |
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| 32 | #ifdef HAVE_KRB5
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| 33 |
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| 34 | #if !defined(HAVE_KRB5_PRINC_COMPONENT)
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| 35 | const krb5_data *krb5_princ_component(krb5_context, krb5_principal, int );
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| 36 | #endif
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| 37 |
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| 38 | static bool ads_dedicated_keytab_verify_ticket(krb5_context context,
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| 39 | krb5_auth_context auth_context,
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| 40 | const DATA_BLOB *ticket,
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| 41 | krb5_ticket **pp_tkt,
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| 42 | krb5_keyblock **keyblock,
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| 43 | krb5_error_code *perr)
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| 44 | {
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| 45 | krb5_error_code ret = 0;
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| 46 | bool auth_ok = false;
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| 47 | krb5_keytab keytab = NULL;
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| 48 | krb5_keytab_entry kt_entry;
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| 49 | krb5_ticket *dec_ticket = NULL;
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| 50 |
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| 51 | krb5_data packet;
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| 52 | krb5_kvno kvno = 0;
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| 53 | krb5_enctype enctype;
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| 54 |
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| 55 | *pp_tkt = NULL;
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| 56 | *keyblock = NULL;
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| 57 | *perr = 0;
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| 58 |
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| 59 | ZERO_STRUCT(kt_entry);
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| 60 |
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| 61 | ret = smb_krb5_open_keytab(context, lp_dedicated_keytab_file(), true,
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| 62 | &keytab);
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| 63 | if (ret) {
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| 64 | DEBUG(1, ("smb_krb5_open_keytab failed (%s)\n",
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| 65 | error_message(ret)));
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| 66 | goto out;
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| 67 | }
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| 68 |
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| 69 | packet.length = ticket->length;
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| 70 | packet.data = (char *)ticket->data;
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| 71 |
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| 72 | ret = krb5_rd_req(context, &auth_context, &packet, NULL, keytab,
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| 73 | NULL, &dec_ticket);
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| 74 | if (ret) {
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| 75 | DEBUG(0, ("krb5_rd_req failed (%s)\n", error_message(ret)));
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| 76 | goto out;
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| 77 | }
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| 78 |
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| 79 | #ifdef HAVE_ETYPE_IN_ENCRYPTEDDATA /* Heimdal */
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| 80 | enctype = dec_ticket->ticket.key.keytype;
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| 81 | #else /* MIT */
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| 82 | enctype = dec_ticket->enc_part.enctype;
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| 83 | kvno = dec_ticket->enc_part.kvno;
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| 84 | #endif
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| 85 |
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| 86 | /* Get the key for checking the pac signature */
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| 87 | ret = krb5_kt_get_entry(context, keytab, dec_ticket->server,
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| 88 | kvno, enctype, &kt_entry);
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| 89 | if (ret) {
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| 90 | DEBUG(0, ("krb5_kt_get_entry failed (%s)\n",
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| 91 | error_message(ret)));
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| 92 | goto out;
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| 93 | }
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| 94 |
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| 95 | ret = krb5_copy_keyblock(context, KRB5_KT_KEY(&kt_entry), keyblock);
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| 96 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 97 |
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| 98 | if (ret) {
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| 99 | DEBUG(0, ("failed to copy key: %s\n",
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| 100 | error_message(ret)));
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| 101 | goto out;
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| 102 | }
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| 103 |
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| 104 | auth_ok = true;
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| 105 | *pp_tkt = dec_ticket;
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| 106 | dec_ticket = NULL;
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| 107 |
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| 108 | out:
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| 109 | if (dec_ticket)
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| 110 | krb5_free_ticket(context, dec_ticket);
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| 111 |
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| 112 | if (keytab)
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| 113 | krb5_kt_close(context, keytab);
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| 114 |
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| 115 | *perr = ret;
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| 116 | return auth_ok;
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| 117 | }
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| 118 |
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| 119 | /******************************************************************************
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| 120 | Try to verify a ticket using the system keytab... the system keytab has
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| 121 | kvno -1 entries, so it's more like what microsoft does... see comment in
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| 122 | utils/net_ads.c in the ads_keytab_add_entry function for details.
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| 123 | ******************************************************************************/
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| 124 |
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| 125 | static bool ads_keytab_verify_ticket(krb5_context context,
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| 126 | krb5_auth_context auth_context,
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| 127 | const DATA_BLOB *ticket,
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| 128 | krb5_ticket **pp_tkt,
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| 129 | krb5_keyblock **keyblock,
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| 130 | krb5_error_code *perr)
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| 131 | {
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| 132 | krb5_error_code ret = 0;
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| 133 | bool auth_ok = False;
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| 134 | krb5_keytab keytab = NULL;
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| 135 | krb5_kt_cursor kt_cursor;
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| 136 | krb5_keytab_entry kt_entry;
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| 137 | char *valid_princ_formats[7] = { NULL, NULL, NULL,
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| 138 | NULL, NULL, NULL, NULL };
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| 139 | char *entry_princ_s = NULL;
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| 140 | fstring my_name, my_fqdn;
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| 141 | int i;
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| 142 | int number_matched_principals = 0;
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| 143 | krb5_data packet;
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| 144 | int err;
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| 145 |
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| 146 | *pp_tkt = NULL;
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| 147 | *keyblock = NULL;
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| 148 | *perr = 0;
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| 149 |
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| 150 | /* Generate the list of principal names which we expect
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| 151 | * clients might want to use for authenticating to the file
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| 152 | * service. We allow name$,{host,cifs}/{name,fqdn,name.REALM}. */
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| 153 |
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| 154 | fstrcpy(my_name, global_myname());
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| 155 |
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| 156 | my_fqdn[0] = '\0';
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| 157 | name_to_fqdn(my_fqdn, global_myname());
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| 158 |
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| 159 | err = asprintf(&valid_princ_formats[0],
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| 160 | "%s$@%s", my_name, lp_realm());
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| 161 | if (err == -1) {
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| 162 | goto out;
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| 163 | }
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| 164 | err = asprintf(&valid_princ_formats[1],
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| 165 | "host/%s@%s", my_name, lp_realm());
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| 166 | if (err == -1) {
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| 167 | goto out;
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| 168 | }
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| 169 | err = asprintf(&valid_princ_formats[2],
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| 170 | "host/%s@%s", my_fqdn, lp_realm());
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| 171 | if (err == -1) {
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| 172 | goto out;
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| 173 | }
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| 174 | err = asprintf(&valid_princ_formats[3],
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| 175 | "host/%s.%s@%s", my_name, lp_realm(), lp_realm());
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| 176 | if (err == -1) {
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| 177 | goto out;
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| 178 | }
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| 179 | err = asprintf(&valid_princ_formats[4],
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| 180 | "cifs/%s@%s", my_name, lp_realm());
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| 181 | if (err == -1) {
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| 182 | goto out;
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| 183 | }
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| 184 | err = asprintf(&valid_princ_formats[5],
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| 185 | "cifs/%s@%s", my_fqdn, lp_realm());
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| 186 | if (err == -1) {
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| 187 | goto out;
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| 188 | }
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| 189 | err = asprintf(&valid_princ_formats[6],
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| 190 | "cifs/%s.%s@%s", my_name, lp_realm(), lp_realm());
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| 191 | if (err == -1) {
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| 192 | goto out;
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| 193 | }
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| 194 |
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| 195 | ZERO_STRUCT(kt_entry);
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| 196 | ZERO_STRUCT(kt_cursor);
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| 197 |
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| 198 | ret = smb_krb5_open_keytab(context, NULL, False, &keytab);
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| 199 | if (ret) {
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| 200 | DEBUG(1, (__location__ ": smb_krb5_open_keytab failed (%s)\n",
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| 201 | error_message(ret)));
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| 202 | goto out;
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| 203 | }
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| 204 |
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| 205 | /* Iterate through the keytab. For each key, if the principal
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| 206 | * name case-insensitively matches one of the allowed formats,
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| 207 | * try verifying the ticket using that principal. */
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| 208 |
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| 209 | ret = krb5_kt_start_seq_get(context, keytab, &kt_cursor);
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| 210 | if (ret) {
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| 211 | DEBUG(1, (__location__ ": krb5_kt_start_seq_get failed (%s)\n",
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| 212 | error_message(ret)));
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| 213 | goto out;
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| 214 | }
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| 215 |
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| 216 | while (!auth_ok &&
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| 217 | (krb5_kt_next_entry(context, keytab,
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| 218 | &kt_entry, &kt_cursor) == 0)) {
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| 219 | ret = smb_krb5_unparse_name(talloc_tos(), context,
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| 220 | kt_entry.principal,
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| 221 | &entry_princ_s);
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| 222 | if (ret) {
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| 223 | DEBUG(1, (__location__ ": smb_krb5_unparse_name "
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| 224 | "failed (%s)\n", error_message(ret)));
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| 225 | goto out;
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| 226 | }
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| 227 |
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| 228 | for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
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| 229 |
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| 230 | if (!strequal(entry_princ_s, valid_princ_formats[i])) {
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| 231 | continue;
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| 232 | }
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| 233 |
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| 234 | number_matched_principals++;
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| 235 | packet.length = ticket->length;
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| 236 | packet.data = (char *)ticket->data;
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| 237 | *pp_tkt = NULL;
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| 238 |
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| 239 | ret = krb5_rd_req_return_keyblock_from_keytab(context,
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| 240 | &auth_context, &packet,
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| 241 | kt_entry.principal, keytab,
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| 242 | NULL, pp_tkt, keyblock);
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| 243 |
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| 244 | if (ret) {
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| 245 | DEBUG(10, (__location__ ": krb5_rd_req_return"
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| 246 | "_keyblock_from_keytab(%s) "
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| 247 | "failed: %s\n", entry_princ_s,
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| 248 | error_message(ret)));
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| 249 |
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| 250 | /* workaround for MIT:
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| 251 | * as krb5_ktfile_get_entry will explicitly
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| 252 | * close the krb5_keytab as soon as krb5_rd_req
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| 253 | * has successfully decrypted the ticket but the
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| 254 | * ticket is not valid yet (due to clockskew)
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| 255 | * there is no point in querying more keytab
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| 256 | * entries - Guenther */
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| 257 |
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| 258 | if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
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| 259 | ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
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| 260 | ret == KRB5KRB_AP_ERR_SKEW) {
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| 261 | break;
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| 262 | }
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| 263 | } else {
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| 264 | DEBUG(3, (__location__ ": krb5_rd_req_return"
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| 265 | "_keyblock_from_keytab succeeded "
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| 266 | "for principal %s\n",
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| 267 | entry_princ_s));
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| 268 | auth_ok = True;
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| 269 | break;
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| 270 | }
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| 271 | }
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| 272 |
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| 273 | /* Free the name we parsed. */
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| 274 | TALLOC_FREE(entry_princ_s);
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| 275 |
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| 276 | /* Free the entry we just read. */
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| 277 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 278 | ZERO_STRUCT(kt_entry);
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| 279 | }
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| 280 | krb5_kt_end_seq_get(context, keytab, &kt_cursor);
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| 281 |
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| 282 | ZERO_STRUCT(kt_cursor);
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| 283 |
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| 284 | out:
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| 285 |
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| 286 | for (i = 0; i < ARRAY_SIZE(valid_princ_formats); i++) {
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| 287 | SAFE_FREE(valid_princ_formats[i]);
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| 288 | }
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| 289 |
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| 290 | if (!auth_ok) {
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| 291 | if (!number_matched_principals) {
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| 292 | DEBUG(3, (__location__ ": no keytab principals "
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| 293 | "matched expected file service name.\n"));
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| 294 | } else {
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| 295 | DEBUG(3, (__location__ ": krb5_rd_req failed for "
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| 296 | "all %d matched keytab principals\n",
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| 297 | number_matched_principals));
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| 298 | }
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| 299 | }
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| 300 |
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| 301 | TALLOC_FREE(entry_princ_s);
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| 302 |
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| 303 | {
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| 304 | krb5_keytab_entry zero_kt_entry;
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| 305 | ZERO_STRUCT(zero_kt_entry);
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| 306 | if (memcmp(&zero_kt_entry, &kt_entry,
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| 307 | sizeof(krb5_keytab_entry))) {
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| 308 | smb_krb5_kt_free_entry(context, &kt_entry);
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| 309 | }
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| 310 | }
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| 311 |
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| 312 | {
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| 313 | krb5_kt_cursor zero_csr;
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| 314 | ZERO_STRUCT(zero_csr);
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| 315 | if ((memcmp(&kt_cursor, &zero_csr,
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| 316 | sizeof(krb5_kt_cursor)) != 0) && keytab) {
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| 317 | krb5_kt_end_seq_get(context, keytab, &kt_cursor);
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| 318 | }
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| 319 | }
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| 320 |
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| 321 | if (keytab) {
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| 322 | krb5_kt_close(context, keytab);
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| 323 | }
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| 324 | *perr = ret;
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| 325 | return auth_ok;
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| 326 | }
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| 327 |
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| 328 | /*****************************************************************************
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| 329 | Try to verify a ticket using the secrets.tdb.
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| 330 | ******************************************************************************/
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| 331 |
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| 332 | static krb5_error_code ads_secrets_verify_ticket(krb5_context context,
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| 333 | krb5_auth_context auth_context,
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| 334 | krb5_principal host_princ,
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| 335 | const DATA_BLOB *ticket,
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| 336 | krb5_ticket **pp_tkt,
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| 337 | krb5_keyblock **keyblock,
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| 338 | krb5_error_code *perr)
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| 339 | {
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| 340 | krb5_error_code ret = 0;
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| 341 | bool auth_ok = False;
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| 342 | bool cont = true;
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| 343 | char *password_s = NULL;
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| 344 | /* Let's make some room for 2 password (old and new)*/
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| 345 | krb5_data passwords[2];
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| 346 | krb5_enctype enctypes[] = {
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| 347 | ENCTYPE_ARCFOUR_HMAC,
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| 348 | ENCTYPE_DES_CBC_CRC,
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| 349 | ENCTYPE_DES_CBC_MD5,
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| 350 | ENCTYPE_NULL
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| 351 | };
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| 352 | krb5_data packet;
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| 353 | int i, j;
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| 354 |
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| 355 | *pp_tkt = NULL;
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| 356 | *keyblock = NULL;
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| 357 | *perr = 0;
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| 358 |
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| 359 | ZERO_STRUCT(passwords);
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| 360 |
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| 361 | if (!secrets_init()) {
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| 362 | DEBUG(1,("ads_secrets_verify_ticket: secrets_init failed\n"));
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| 363 | *perr = KRB5_CONFIG_CANTOPEN;
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| 364 | return False;
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| 365 | }
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| 366 |
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| 367 | password_s = secrets_fetch_machine_password(lp_workgroup(),
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| 368 | NULL, NULL);
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| 369 | if (!password_s) {
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| 370 | DEBUG(1,(__location__ ": failed to fetch machine password\n"));
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| 371 | *perr = KRB5_LIBOS_CANTREADPWD;
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| 372 | return False;
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| 373 | }
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| 374 |
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| 375 | passwords[0].data = password_s;
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| 376 | passwords[0].length = strlen(password_s);
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| 377 |
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| 378 | password_s = secrets_fetch_prev_machine_password(lp_workgroup());
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| 379 | if (password_s) {
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| 380 | DEBUG(10, (__location__ ": found previous password\n"));
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| 381 | passwords[1].data = password_s;
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| 382 | passwords[1].length = strlen(password_s);
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| 383 | }
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| 384 |
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| 385 | /* CIFS doesn't use addresses in tickets. This would break NAT. JRA */
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| 386 |
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| 387 | packet.length = ticket->length;
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| 388 | packet.data = (char *)ticket->data;
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| 389 |
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| 390 | /* We need to setup a auth context with each possible encoding type
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| 391 | * in turn. */
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| 392 | for (j=0; j<2 && passwords[j].length; j++) {
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| 393 |
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| 394 | for (i=0;enctypes[i];i++) {
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| 395 | krb5_keyblock *key = NULL;
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| 396 |
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| 397 | if (!(key = SMB_MALLOC_P(krb5_keyblock))) {
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| 398 | ret = ENOMEM;
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| 399 | goto out;
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| 400 | }
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| 401 |
|
|---|
| 402 | if (create_kerberos_key_from_string(context,
|
|---|
| 403 | host_princ, &passwords[j],
|
|---|
| 404 | key, enctypes[i], false)) {
|
|---|
| 405 | SAFE_FREE(key);
|
|---|
| 406 | continue;
|
|---|
| 407 | }
|
|---|
| 408 |
|
|---|
| 409 | krb5_auth_con_setuseruserkey(context,
|
|---|
| 410 | auth_context, key);
|
|---|
| 411 |
|
|---|
| 412 | if (!(ret = krb5_rd_req(context, &auth_context,
|
|---|
| 413 | &packet, NULL, NULL,
|
|---|
| 414 | NULL, pp_tkt))) {
|
|---|
| 415 | DEBUG(10, (__location__ ": enc type [%u] "
|
|---|
| 416 | "decrypted message !\n",
|
|---|
| 417 | (unsigned int)enctypes[i]));
|
|---|
| 418 | auth_ok = True;
|
|---|
| 419 | cont = false;
|
|---|
| 420 | krb5_copy_keyblock(context, key, keyblock);
|
|---|
| 421 | krb5_free_keyblock(context, key);
|
|---|
| 422 | break;
|
|---|
| 423 | }
|
|---|
| 424 |
|
|---|
| 425 | DEBUG((ret != KRB5_BAD_ENCTYPE) ? 3 : 10,
|
|---|
| 426 | (__location__ ": enc type [%u] failed to "
|
|---|
| 427 | "decrypt with error %s\n",
|
|---|
| 428 | (unsigned int)enctypes[i],
|
|---|
| 429 | error_message(ret)));
|
|---|
| 430 |
|
|---|
| 431 | /* successfully decrypted but ticket is just not
|
|---|
| 432 | * valid at the moment */
|
|---|
| 433 | if (ret == KRB5KRB_AP_ERR_TKT_NYV ||
|
|---|
| 434 | ret == KRB5KRB_AP_ERR_TKT_EXPIRED ||
|
|---|
| 435 | ret == KRB5KRB_AP_ERR_SKEW) {
|
|---|
| 436 | krb5_free_keyblock(context, key);
|
|---|
| 437 | cont = false;
|
|---|
| 438 | break;
|
|---|
| 439 | }
|
|---|
| 440 |
|
|---|
| 441 | krb5_free_keyblock(context, key);
|
|---|
| 442 | }
|
|---|
| 443 | if (!cont) {
|
|---|
| 444 | /* If we found a valid pass then no need to try
|
|---|
| 445 | * the next one or we have invalid ticket so no need
|
|---|
| 446 | * to try next password*/
|
|---|
| 447 | break;
|
|---|
| 448 | }
|
|---|
| 449 | }
|
|---|
| 450 |
|
|---|
| 451 | out:
|
|---|
| 452 | SAFE_FREE(passwords[0].data);
|
|---|
| 453 | SAFE_FREE(passwords[1].data);
|
|---|
| 454 | *perr = ret;
|
|---|
| 455 | return auth_ok;
|
|---|
| 456 | }
|
|---|
| 457 |
|
|---|
| 458 | /*****************************************************************************
|
|---|
| 459 | Verify an incoming ticket and parse out the principal name and
|
|---|
| 460 | authorization_data if available.
|
|---|
| 461 | ******************************************************************************/
|
|---|
| 462 |
|
|---|
| 463 | NTSTATUS ads_verify_ticket(TALLOC_CTX *mem_ctx,
|
|---|
| 464 | const char *realm,
|
|---|
| 465 | time_t time_offset,
|
|---|
| 466 | const DATA_BLOB *ticket,
|
|---|
| 467 | char **principal,
|
|---|
| 468 | struct PAC_LOGON_INFO **logon_info,
|
|---|
| 469 | DATA_BLOB *ap_rep,
|
|---|
| 470 | DATA_BLOB *session_key,
|
|---|
| 471 | bool use_replay_cache)
|
|---|
| 472 | {
|
|---|
| 473 | NTSTATUS sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 474 | NTSTATUS pac_ret;
|
|---|
| 475 | DATA_BLOB auth_data;
|
|---|
| 476 | krb5_context context = NULL;
|
|---|
| 477 | krb5_auth_context auth_context = NULL;
|
|---|
| 478 | krb5_data packet;
|
|---|
| 479 | krb5_ticket *tkt = NULL;
|
|---|
| 480 | krb5_rcache rcache = NULL;
|
|---|
| 481 | krb5_keyblock *keyblock = NULL;
|
|---|
| 482 | time_t authtime;
|
|---|
| 483 | krb5_error_code ret = 0;
|
|---|
| 484 | int flags = 0;
|
|---|
| 485 | krb5_principal host_princ = NULL;
|
|---|
| 486 | krb5_const_principal client_principal = NULL;
|
|---|
| 487 | char *host_princ_s = NULL;
|
|---|
| 488 | bool auth_ok = False;
|
|---|
| 489 | bool got_auth_data = False;
|
|---|
| 490 | struct named_mutex *mutex = NULL;
|
|---|
| 491 |
|
|---|
| 492 | ZERO_STRUCT(packet);
|
|---|
| 493 | ZERO_STRUCT(auth_data);
|
|---|
| 494 |
|
|---|
| 495 | *principal = NULL;
|
|---|
| 496 | *logon_info = NULL;
|
|---|
| 497 | *ap_rep = data_blob_null;
|
|---|
| 498 | *session_key = data_blob_null;
|
|---|
| 499 |
|
|---|
| 500 | initialize_krb5_error_table();
|
|---|
| 501 | ret = krb5_init_context(&context);
|
|---|
| 502 | if (ret) {
|
|---|
| 503 | DEBUG(1, (__location__ ": krb5_init_context failed (%s)\n",
|
|---|
| 504 | error_message(ret)));
|
|---|
| 505 | return NT_STATUS_LOGON_FAILURE;
|
|---|
| 506 | }
|
|---|
| 507 |
|
|---|
| 508 | if (time_offset != 0) {
|
|---|
| 509 | krb5_set_real_time(context, time(NULL) + time_offset, 0);
|
|---|
| 510 | }
|
|---|
| 511 |
|
|---|
| 512 | ret = krb5_set_default_realm(context, realm);
|
|---|
| 513 | if (ret) {
|
|---|
| 514 | DEBUG(1, (__location__ ": krb5_set_default_realm "
|
|---|
| 515 | "failed (%s)\n", error_message(ret)));
|
|---|
| 516 | goto out;
|
|---|
| 517 | }
|
|---|
| 518 |
|
|---|
| 519 | /* This whole process is far more complex than I would
|
|---|
| 520 | like. We have to go through all this to allow us to store
|
|---|
| 521 | the secret internally, instead of using /etc/krb5.keytab */
|
|---|
| 522 |
|
|---|
| 523 | ret = krb5_auth_con_init(context, &auth_context);
|
|---|
| 524 | if (ret) {
|
|---|
| 525 | DEBUG(1, (__location__ ": krb5_auth_con_init failed (%s)\n",
|
|---|
| 526 | error_message(ret)));
|
|---|
| 527 | goto out;
|
|---|
| 528 | }
|
|---|
| 529 |
|
|---|
| 530 | krb5_auth_con_getflags( context, auth_context, &flags );
|
|---|
| 531 | if ( !use_replay_cache ) {
|
|---|
| 532 | /* Disable default use of a replay cache */
|
|---|
| 533 | flags &= ~KRB5_AUTH_CONTEXT_DO_TIME;
|
|---|
| 534 | krb5_auth_con_setflags( context, auth_context, flags );
|
|---|
| 535 | }
|
|---|
| 536 |
|
|---|
| 537 | if (asprintf(&host_princ_s, "%s$", global_myname()) == -1) {
|
|---|
| 538 | goto out;
|
|---|
| 539 | }
|
|---|
| 540 |
|
|---|
| 541 | strlower_m(host_princ_s);
|
|---|
| 542 | ret = smb_krb5_parse_name(context, host_princ_s, &host_princ);
|
|---|
| 543 | if (ret) {
|
|---|
| 544 | DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
|
|---|
| 545 | "failed (%s)\n", host_princ_s, error_message(ret)));
|
|---|
| 546 | goto out;
|
|---|
| 547 | }
|
|---|
| 548 |
|
|---|
| 549 |
|
|---|
| 550 | if (use_replay_cache) {
|
|---|
| 551 |
|
|---|
| 552 | /* Lock a mutex surrounding the replay as there is no
|
|---|
| 553 | locking in the MIT krb5 code surrounding the replay
|
|---|
| 554 | cache... */
|
|---|
| 555 |
|
|---|
| 556 | mutex = grab_named_mutex(talloc_tos(),
|
|---|
| 557 | "replay cache mutex", 10);
|
|---|
| 558 | if (mutex == NULL) {
|
|---|
| 559 | DEBUG(1, (__location__ ": unable to protect replay "
|
|---|
| 560 | "cache with mutex.\n"));
|
|---|
| 561 | ret = KRB5_CC_IO;
|
|---|
| 562 | goto out;
|
|---|
| 563 | }
|
|---|
| 564 |
|
|---|
| 565 | /* JRA. We must set the rcache here. This will prevent
|
|---|
| 566 | replay attacks. */
|
|---|
| 567 |
|
|---|
| 568 | ret = krb5_get_server_rcache(
|
|---|
| 569 | context,
|
|---|
| 570 | krb5_princ_component(context, host_princ, 0),
|
|---|
| 571 | &rcache);
|
|---|
| 572 | if (ret) {
|
|---|
| 573 | DEBUG(1, (__location__ ": krb5_get_server_rcache "
|
|---|
| 574 | "failed (%s)\n", error_message(ret)));
|
|---|
| 575 | goto out;
|
|---|
| 576 | }
|
|---|
| 577 |
|
|---|
| 578 | ret = krb5_auth_con_setrcache(context, auth_context, rcache);
|
|---|
| 579 | if (ret) {
|
|---|
| 580 | DEBUG(1, (__location__ ": krb5_auth_con_setrcache "
|
|---|
| 581 | "failed (%s)\n", error_message(ret)));
|
|---|
| 582 | goto out;
|
|---|
| 583 | }
|
|---|
| 584 | }
|
|---|
| 585 |
|
|---|
| 586 | switch (lp_kerberos_method()) {
|
|---|
| 587 | default:
|
|---|
| 588 | case KERBEROS_VERIFY_SECRETS:
|
|---|
| 589 | auth_ok = ads_secrets_verify_ticket(context, auth_context,
|
|---|
| 590 | host_princ, ticket, &tkt, &keyblock, &ret);
|
|---|
| 591 | break;
|
|---|
| 592 | case KERBEROS_VERIFY_SYSTEM_KEYTAB:
|
|---|
| 593 | auth_ok = ads_keytab_verify_ticket(context, auth_context,
|
|---|
| 594 | ticket, &tkt, &keyblock, &ret);
|
|---|
| 595 | break;
|
|---|
| 596 | case KERBEROS_VERIFY_DEDICATED_KEYTAB:
|
|---|
| 597 | auth_ok = ads_dedicated_keytab_verify_ticket(context,
|
|---|
| 598 | auth_context, ticket, &tkt, &keyblock, &ret);
|
|---|
| 599 | break;
|
|---|
| 600 | case KERBEROS_VERIFY_SECRETS_AND_KEYTAB:
|
|---|
| 601 | /* First try secrets.tdb and fallback to the krb5.keytab if
|
|---|
| 602 | necessary. This is the pre 3.4 behavior when
|
|---|
| 603 | "use kerberos keytab" was true.*/
|
|---|
| 604 | auth_ok = ads_secrets_verify_ticket(context, auth_context,
|
|---|
| 605 | host_princ, ticket, &tkt, &keyblock, &ret);
|
|---|
| 606 |
|
|---|
| 607 | if (!auth_ok) {
|
|---|
| 608 | /* Only fallback if we failed to decrypt the ticket */
|
|---|
| 609 | if (ret != KRB5KRB_AP_ERR_TKT_NYV &&
|
|---|
| 610 | ret != KRB5KRB_AP_ERR_TKT_EXPIRED &&
|
|---|
| 611 | ret != KRB5KRB_AP_ERR_SKEW) {
|
|---|
| 612 | auth_ok = ads_keytab_verify_ticket(context,
|
|---|
| 613 | auth_context, ticket, &tkt, &keyblock,
|
|---|
| 614 | &ret);
|
|---|
| 615 | }
|
|---|
| 616 | }
|
|---|
| 617 | break;
|
|---|
| 618 | }
|
|---|
| 619 |
|
|---|
| 620 | if (use_replay_cache) {
|
|---|
| 621 | TALLOC_FREE(mutex);
|
|---|
| 622 | #if 0
|
|---|
| 623 | /* Heimdal leaks here, if we fix the leak, MIT crashes */
|
|---|
| 624 | if (rcache) {
|
|---|
| 625 | krb5_rc_close(context, rcache);
|
|---|
| 626 | }
|
|---|
| 627 | #endif
|
|---|
| 628 | }
|
|---|
| 629 |
|
|---|
| 630 | if (!auth_ok) {
|
|---|
| 631 | DEBUG(3, (__location__ ": krb5_rd_req with auth "
|
|---|
| 632 | "failed (%s)\n", error_message(ret)));
|
|---|
| 633 | /* Try map the error return in case it's something like
|
|---|
| 634 | * a clock skew error.
|
|---|
| 635 | */
|
|---|
| 636 | sret = krb5_to_nt_status(ret);
|
|---|
| 637 | if (NT_STATUS_IS_OK(sret) ||
|
|---|
| 638 | NT_STATUS_EQUAL(sret,NT_STATUS_UNSUCCESSFUL)) {
|
|---|
| 639 | sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 640 | }
|
|---|
| 641 | DEBUG(10, (__location__ ": returning error %s\n",
|
|---|
| 642 | nt_errstr(sret) ));
|
|---|
| 643 | goto out;
|
|---|
| 644 | }
|
|---|
| 645 |
|
|---|
| 646 | authtime = get_authtime_from_tkt(tkt);
|
|---|
| 647 | client_principal = get_principal_from_tkt(tkt);
|
|---|
| 648 |
|
|---|
| 649 | ret = krb5_mk_rep(context, auth_context, &packet);
|
|---|
| 650 | if (ret) {
|
|---|
| 651 | DEBUG(3, (__location__ ": Failed to generate mutual "
|
|---|
| 652 | "authentication reply (%s)\n", error_message(ret)));
|
|---|
| 653 | goto out;
|
|---|
| 654 | }
|
|---|
| 655 |
|
|---|
| 656 | *ap_rep = data_blob(packet.data, packet.length);
|
|---|
| 657 | if (packet.data) {
|
|---|
| 658 | kerberos_free_data_contents(context, &packet);
|
|---|
| 659 | ZERO_STRUCT(packet);
|
|---|
| 660 | }
|
|---|
| 661 |
|
|---|
| 662 | get_krb5_smb_session_key(mem_ctx, context,
|
|---|
| 663 | auth_context, session_key, true);
|
|---|
| 664 | dump_data_pw("SMB session key (from ticket)\n",
|
|---|
| 665 | session_key->data, session_key->length);
|
|---|
| 666 |
|
|---|
| 667 | #if 0
|
|---|
| 668 | file_save("/tmp/ticket.dat", ticket->data, ticket->length);
|
|---|
| 669 | #endif
|
|---|
| 670 |
|
|---|
| 671 | /* continue when no PAC is retrieved or we couldn't decode the PAC
|
|---|
| 672 | (like accounts that have the UF_NO_AUTH_DATA_REQUIRED flag set, or
|
|---|
| 673 | Kerberos tickets encrypted using a DES key) - Guenther */
|
|---|
| 674 |
|
|---|
| 675 | got_auth_data = get_auth_data_from_tkt(mem_ctx, &auth_data, tkt);
|
|---|
| 676 | if (!got_auth_data) {
|
|---|
| 677 | DEBUG(3, (__location__ ": did not retrieve auth data. "
|
|---|
| 678 | "continuing without PAC\n"));
|
|---|
| 679 | }
|
|---|
| 680 |
|
|---|
| 681 | if (got_auth_data) {
|
|---|
| 682 | struct PAC_DATA *pac_data;
|
|---|
| 683 | pac_ret = decode_pac_data(mem_ctx, &auth_data, context,
|
|---|
| 684 | keyblock, client_principal,
|
|---|
| 685 | authtime, &pac_data);
|
|---|
| 686 | data_blob_free(&auth_data);
|
|---|
| 687 | if (!NT_STATUS_IS_OK(pac_ret)) {
|
|---|
| 688 | DEBUG(3, (__location__ ": failed to decode "
|
|---|
| 689 | "PAC_DATA: %s\n", nt_errstr(pac_ret)));
|
|---|
| 690 | } else {
|
|---|
| 691 | uint32_t i;
|
|---|
| 692 | for (i = 0; i < pac_data->num_buffers; i++) {
|
|---|
| 693 |
|
|---|
| 694 | if (pac_data->buffers[i].type != PAC_TYPE_LOGON_INFO) {
|
|---|
| 695 | continue;
|
|---|
| 696 | }
|
|---|
| 697 |
|
|---|
| 698 | *logon_info = pac_data->buffers[i].info->logon_info.info;
|
|---|
| 699 | }
|
|---|
| 700 |
|
|---|
| 701 | if (!*logon_info) {
|
|---|
| 702 | DEBUG(1, ("correctly decoded PAC but found "
|
|---|
| 703 | "no logon_info! "
|
|---|
| 704 | "This should not happen\n"));
|
|---|
| 705 | return NT_STATUS_INVALID_USER_BUFFER;
|
|---|
| 706 | }
|
|---|
| 707 | }
|
|---|
| 708 | }
|
|---|
| 709 |
|
|---|
| 710 | #if 0
|
|---|
| 711 | #if defined(HAVE_KRB5_TKT_ENC_PART2)
|
|---|
| 712 | /* MIT */
|
|---|
| 713 | if (tkt->enc_part2) {
|
|---|
| 714 | file_save("/tmp/authdata.dat",
|
|---|
| 715 | tkt->enc_part2->authorization_data[0]->contents,
|
|---|
| 716 | tkt->enc_part2->authorization_data[0]->length);
|
|---|
| 717 | }
|
|---|
| 718 | #else
|
|---|
| 719 | /* Heimdal */
|
|---|
| 720 | if (tkt->ticket.authorization_data) {
|
|---|
| 721 | file_save("/tmp/authdata.dat",
|
|---|
| 722 | tkt->ticket.authorization_data->val->ad_data.data,
|
|---|
| 723 | tkt->ticket.authorization_data->val->ad_data.length);
|
|---|
| 724 | }
|
|---|
| 725 | #endif
|
|---|
| 726 | #endif
|
|---|
| 727 |
|
|---|
| 728 | ret = smb_krb5_unparse_name(mem_ctx, context,
|
|---|
| 729 | client_principal, principal);
|
|---|
| 730 | if (ret) {
|
|---|
| 731 | DEBUG(3, (__location__ ": smb_krb5_unparse_name "
|
|---|
| 732 | "failed (%s)\n", error_message(ret)));
|
|---|
| 733 | sret = NT_STATUS_LOGON_FAILURE;
|
|---|
| 734 | goto out;
|
|---|
| 735 | }
|
|---|
| 736 |
|
|---|
| 737 | sret = NT_STATUS_OK;
|
|---|
| 738 |
|
|---|
| 739 | out:
|
|---|
| 740 |
|
|---|
| 741 | TALLOC_FREE(mutex);
|
|---|
| 742 |
|
|---|
| 743 | if (!NT_STATUS_IS_OK(sret)) {
|
|---|
| 744 | data_blob_free(&auth_data);
|
|---|
| 745 | }
|
|---|
| 746 |
|
|---|
| 747 | if (!NT_STATUS_IS_OK(sret)) {
|
|---|
| 748 | data_blob_free(ap_rep);
|
|---|
| 749 | }
|
|---|
| 750 |
|
|---|
| 751 | if (host_princ) {
|
|---|
| 752 | krb5_free_principal(context, host_princ);
|
|---|
| 753 | }
|
|---|
| 754 |
|
|---|
| 755 | if (keyblock) {
|
|---|
| 756 | krb5_free_keyblock(context, keyblock);
|
|---|
| 757 | }
|
|---|
| 758 |
|
|---|
| 759 | if (tkt != NULL) {
|
|---|
| 760 | krb5_free_ticket(context, tkt);
|
|---|
| 761 | }
|
|---|
| 762 |
|
|---|
| 763 | SAFE_FREE(host_princ_s);
|
|---|
| 764 |
|
|---|
| 765 | if (auth_context) {
|
|---|
| 766 | krb5_auth_con_free(context, auth_context);
|
|---|
| 767 | }
|
|---|
| 768 |
|
|---|
| 769 | if (context) {
|
|---|
| 770 | krb5_free_context(context);
|
|---|
| 771 | }
|
|---|
| 772 |
|
|---|
| 773 | return sret;
|
|---|
| 774 | }
|
|---|
| 775 |
|
|---|
| 776 | #endif /* HAVE_KRB5 */
|
|---|