auth/gensec/gensec_util.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Generic Authentication Interface
   5
   6    Copyright (C) Andrew Tridgell 2003
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2006
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "auth/gensec/gensec.h"
  25 #include "auth/gensec/gensec_internal.h"
  26 #include "auth/common_auth.h"
  27 #include "../lib/util/asn1.h"
  28
  29 NTSTATUS gensec_generate_session_info_pac(TALLOC_CTX *mem_ctx,
  30                                           struct gensec_security *gensec_security,
  31                                           struct smb_krb5_context *smb_krb5_context,
  32                                           DATA_BLOB *pac_blob,
  33                                           const char *principal_string,
  34                                           const struct tsocket_address *remote_address,
  35                                           struct auth_session_info **session_info)
  36 {
  37         uint32_t session_info_flags = 0;
  38
  39         if (gensec_security->want_features & GENSEC_FEATURE_UNIX_TOKEN) {
  40                 session_info_flags |= AUTH_SESSION_INFO_UNIX_TOKEN;
  41         }
  42
  43         session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;
  44
  45         if (!pac_blob) {
  46                 if (gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
  47                         DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access\n",
  48                                   principal_string));
  49                         return NT_STATUS_ACCESS_DENIED;
  50                 }
  51                 DBG_NOTICE("Unable to find PAC for %s, resorting to local "
  52                            "user lookup\n", principal_string);
  53         }
  54
  55         if (gensec_security->auth_context && gensec_security->auth_context->generate_session_info_pac) {
  56                 return gensec_security->auth_context->generate_session_info_pac(gensec_security->auth_context,
  57                                                                                 mem_ctx,
  58                                                                                 smb_krb5_context,
  59                                                                                 pac_blob,
  60                                                                                 principal_string,
  61                                                                                 remote_address,
  62                                                                                 session_info_flags,
  63                                                                                 session_info);
  64         } else {
  65                 DEBUG(0, ("Cannot generate a session_info without the auth_context\n"));
  66                 return NT_STATUS_INTERNAL_ERROR;
  67         }
  68 }
  69
  70 /*
  71   magic check a GSS-API wrapper packet for an Kerberos OID
  72 */
  73 static bool gensec_gssapi_check_oid(const DATA_BLOB *blob, const char *oid)
  74 {
  75         bool ret = false;
  76         struct asn1_data *data = asn1_init(NULL);
  77
  78         if (!data) return false;
  79
  80         if (!asn1_load(data, *blob)) goto err;
  81         if (!asn1_start_tag(data, ASN1_APPLICATION(0))) goto err;
  82         if (!asn1_check_OID(data, oid)) goto err;
  83
  84         ret = !asn1_has_error(data);
  85
  86   err:
  87
  88         asn1_free(data);
  89         return ret;
  90 }
  91
  92 /**
  93  * Check if the packet is one for the KRB5 mechansim
  94  *
  95  * NOTE: This is a helper that can be employed by multiple mechanisms, do
  96  * not make assumptions about the private_data
  97  *
  98  * @param gensec_security GENSEC state, unused
  99  * @param in The request, as a DATA_BLOB
 100  * @return Error, INVALID_PARAMETER if it's not a packet for us
 101  *                or NT_STATUS_OK if the packet is ok.
 102  */
 103
 104 NTSTATUS gensec_magic_check_krb5_oid(struct gensec_security *unused,
 105                                         const DATA_BLOB *blob)
 106 {
 107         if (gensec_gssapi_check_oid(blob, GENSEC_OID_KERBEROS5)) {
 108                 return NT_STATUS_OK;
 109         } else {
 110                 return NT_STATUS_INVALID_PARAMETER;
 111         }
 112 }
 113
 114 void gensec_child_want_feature(struct gensec_security *gensec_security,
 115                                uint32_t feature)
 116 {
 117         struct gensec_security *child_security = gensec_security->child_security;
 118
 119         gensec_security->want_features |= feature;
 120         if (child_security == NULL) {
 121                 return;
 122         }
 123         gensec_want_feature(child_security, feature);
 124 }
 125
 126 bool gensec_child_have_feature(struct gensec_security *gensec_security,
 127                                uint32_t feature)
 128 {
 129         struct gensec_security *child_security = gensec_security->child_security;
 130
 131         if (feature & GENSEC_FEATURE_SIGN_PKT_HEADER) {
 132                 /*
 133                  * All mechs with sub (child) mechs need to provide DCERPC
 134                  * header signing! This is required because the negotiation
 135                  * of header signing is done before the authentication
 136                  * is completed.
 137                  */
 138                 return true;
 139         }
 140
 141         if (child_security == NULL) {
 142                 return false;
 143         }
 144
 145         return gensec_have_feature(child_security, feature);
 146 }
 147
 148 NTSTATUS gensec_child_unseal_packet(struct gensec_security *gensec_security,
 149                                     uint8_t *data, size_t length,
 150                                     const uint8_t *whole_pdu, size_t pdu_length,
 151                                     const DATA_BLOB *sig)
 152 {
 153         if (gensec_security->child_security == NULL) {
 154                 return NT_STATUS_INVALID_PARAMETER;
 155         }
 156
 157         return gensec_unseal_packet(gensec_security->child_security,
 158                                     data, length,
 159                                     whole_pdu, pdu_length,
 160                                     sig);
 161 }
 162
 163 NTSTATUS gensec_child_check_packet(struct gensec_security *gensec_security,
 164                                    const uint8_t *data, size_t length,
 165                                    const uint8_t *whole_pdu, size_t pdu_length,
 166                                    const DATA_BLOB *sig)
 167 {
 168         if (gensec_security->child_security == NULL) {
 169                 return NT_STATUS_INVALID_PARAMETER;
 170         }
 171
 172         return gensec_check_packet(gensec_security->child_security,
 173                                    data, length,
 174                                    whole_pdu, pdu_length,
 175                                    sig);
 176 }
 177
 178 NTSTATUS gensec_child_seal_packet(struct gensec_security *gensec_security,
 179                                   TALLOC_CTX *mem_ctx,
 180                                   uint8_t *data, size_t length,
 181                                   const uint8_t *whole_pdu, size_t pdu_length,
 182                                   DATA_BLOB *sig)
 183 {
 184         if (gensec_security->child_security == NULL) {
 185                 return NT_STATUS_INVALID_PARAMETER;
 186         }
 187
 188         return gensec_seal_packet(gensec_security->child_security,
 189                                   mem_ctx,
 190                                   data, length,
 191                                   whole_pdu, pdu_length,
 192                                   sig);
 193 }
 194
 195 NTSTATUS gensec_child_sign_packet(struct gensec_security *gensec_security,
 196                                   TALLOC_CTX *mem_ctx,
 197                                   const uint8_t *data, size_t length,
 198                                   const uint8_t *whole_pdu, size_t pdu_length,
 199                                   DATA_BLOB *sig)
 200 {
 201         if (gensec_security->child_security == NULL) {
 202                 return NT_STATUS_INVALID_PARAMETER;
 203         }
 204
 205         return gensec_sign_packet(gensec_security->child_security,
 206                                   mem_ctx,
 207                                   data, length,
 208                                   whole_pdu, pdu_length,
 209                                   sig);
 210 }
 211
 212 NTSTATUS gensec_child_wrap(struct gensec_security *gensec_security,
 213                            TALLOC_CTX *mem_ctx,
 214                            const DATA_BLOB *in,
 215                            DATA_BLOB *out)
 216 {
 217         if (gensec_security->child_security == NULL) {
 218                 return NT_STATUS_INVALID_PARAMETER;
 219         }
 220
 221         return gensec_wrap(gensec_security->child_security,
 222                            mem_ctx, in, out);
 223 }
 224
 225 NTSTATUS gensec_child_unwrap(struct gensec_security *gensec_security,
 226                              TALLOC_CTX *mem_ctx,
 227                              const DATA_BLOB *in,
 228                              DATA_BLOB *out)
 229 {
 230         if (gensec_security->child_security == NULL) {
 231                 return NT_STATUS_INVALID_PARAMETER;
 232         }
 233
 234         return gensec_unwrap(gensec_security->child_security,
 235                              mem_ctx, in, out);
 236 }
 237
 238 size_t gensec_child_sig_size(struct gensec_security *gensec_security,
 239                              size_t data_size)
 240 {
 241         if (gensec_security->child_security == NULL) {
 242                 return 0;
 243         }
 244
 245         return gensec_sig_size(gensec_security->child_security, data_size);
 246 }
 247
 248 size_t gensec_child_max_input_size(struct gensec_security *gensec_security)
 249 {
 250         if (gensec_security->child_security == NULL) {
 251                 return 0;
 252         }
 253
 254         return gensec_max_input_size(gensec_security->child_security);
 255 }
 256
 257 size_t gensec_child_max_wrapped_size(struct gensec_security *gensec_security)
 258 {
 259         if (gensec_security->child_security == NULL) {
 260                 return 0;
 261         }
 262
 263         return gensec_max_wrapped_size(gensec_security->child_security);
 264 }
 265
 266 NTSTATUS gensec_child_session_key(struct gensec_security *gensec_security,
 267                                   TALLOC_CTX *mem_ctx,
 268                                   DATA_BLOB *session_key)
 269 {
 270         if (gensec_security->child_security == NULL) {
 271                 return NT_STATUS_INVALID_PARAMETER;
 272         }
 273
 274         return gensec_session_key(gensec_security->child_security,
 275                                   mem_ctx,
 276                                   session_key);
 277 }
 278
 279 NTSTATUS gensec_child_session_info(struct gensec_security *gensec_security,
 280                                    TALLOC_CTX *mem_ctx,
 281                                    struct auth_session_info **session_info)
 282 {
 283         if (gensec_security->child_security == NULL) {
 284                 return NT_STATUS_INVALID_PARAMETER;
 285         }
 286
 287         return gensec_session_info(gensec_security->child_security,
 288                                    mem_ctx,
 289                                    session_info);
 290 }
 291
 292 NTTIME gensec_child_expire_time(struct gensec_security *gensec_security)
 293 {
 294         if (gensec_security->child_security == NULL) {
 295                 return GENSEC_EXPIRE_TIME_INFINITY;
 296         }
 297
 298         return gensec_expire_time(gensec_security->child_security);
 299 }
 300
 301 const char *gensec_child_final_auth_type(struct gensec_security *gensec_security)
 302 {
 303         if (gensec_security->child_security == NULL) {
 304                 return "NONE";
 305         }
 306
 307         return gensec_final_auth_type(gensec_security->child_security);
 308 }