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 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_AUTH
  31
  32 NTSTATUS gensec_generate_session_info_pac(TALLOC_CTX *mem_ctx,
  33                                           struct gensec_security *gensec_security,
  34                                           struct smb_krb5_context *smb_krb5_context,
  35                                           DATA_BLOB *pac_blob,
  36                                           const char *principal_string,
  37                                           const struct tsocket_address *remote_address,
  38                                           struct auth_session_info **session_info)
  39 {
  40         uint32_t session_info_flags = 0;
  41
  42         if (gensec_security->want_features & GENSEC_FEATURE_UNIX_TOKEN) {
  43                 session_info_flags |= AUTH_SESSION_INFO_UNIX_TOKEN;
  44         }
  45
  46         session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;
  47
  48         if (!pac_blob) {
  49                 if (gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
  50                         DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access\n",
  51                                   principal_string));
  52                         return NT_STATUS_ACCESS_DENIED;
  53                 }
  54                 DBG_NOTICE("Unable to find PAC for %s, resorting to local "
  55                            "user lookup\n", principal_string);
  56         }
  57
  58         if (gensec_security->auth_context && gensec_security->auth_context->generate_session_info_pac) {
  59                 return gensec_security->auth_context->generate_session_info_pac(gensec_security->auth_context,
  60                                                                                 mem_ctx,
  61                                                                                 smb_krb5_context,
  62                                                                                 pac_blob,
  63                                                                                 principal_string,
  64                                                                                 remote_address,
  65                                                                                 session_info_flags,
  66                                                                                 session_info);
  67         } else {
  68                 DEBUG(0, ("Cannot generate a session_info without the auth_context\n"));
  69                 return NT_STATUS_INTERNAL_ERROR;
  70         }
  71 }
  72
  73 /*
  74   magic check a GSS-API wrapper packet for an Kerberos OID
  75 */
  76 static bool gensec_gssapi_check_oid(const DATA_BLOB *blob, const char *oid)
  77 {
  78         bool ret = false;
  79         struct asn1_data *data = asn1_init(NULL, ASN1_MAX_TREE_DEPTH);
  80
  81         if (!data) return false;
  82
  83         if (!asn1_load(data, *blob)) goto err;
  84         if (!asn1_start_tag(data, ASN1_APPLICATION(0))) goto err;
  85         if (!asn1_check_OID(data, oid)) goto err;
  86
  87         ret = !asn1_has_error(data);
  88
  89   err:
  90
  91         asn1_free(data);
  92         return ret;
  93 }
  94
  95 /**
  96  * Check if the packet is one for the KRB5 mechansim
  97  *
  98  * NOTE: This is a helper that can be employed by multiple mechanisms, do
  99  * not make assumptions about the private_data
 100  *
 101  * @param gensec_security GENSEC state, unused
 102  * @param in The request, as a DATA_BLOB
 103  * @return Error, INVALID_PARAMETER if it's not a packet for us
 104  *                or NT_STATUS_OK if the packet is ok.
 105  */
 106
 107 NTSTATUS gensec_magic_check_krb5_oid(struct gensec_security *unused,
 108                                         const DATA_BLOB *blob)
 109 {
 110         if (gensec_gssapi_check_oid(blob, GENSEC_OID_KERBEROS5)) {
 111                 return NT_STATUS_OK;
 112         } else {
 113                 return NT_STATUS_INVALID_PARAMETER;
 114         }
 115 }
 116
 117 void gensec_child_want_feature(struct gensec_security *gensec_security,
 118                                uint32_t feature)
 119 {
 120         struct gensec_security *child_security = gensec_security->child_security;
 121
 122         gensec_security->want_features |= feature;
 123         if (child_security == NULL) {
 124                 return;
 125         }
 126         gensec_want_feature(child_security, feature);
 127 }
 128
 129 bool gensec_child_have_feature(struct gensec_security *gensec_security,
 130                                uint32_t feature)
 131 {
 132         struct gensec_security *child_security = gensec_security->child_security;
 133
 134         if (feature & GENSEC_FEATURE_SIGN_PKT_HEADER) {
 135                 /*
 136                  * All mechs with sub (child) mechs need to provide DCERPC
 137                  * header signing! This is required because the negotiation
 138                  * of header signing is done before the authentication
 139                  * is completed.
 140                  */
 141                 return true;
 142         }
 143
 144         if (child_security == NULL) {
 145                 return false;
 146         }
 147
 148         return gensec_have_feature(child_security, feature);
 149 }
 150
 151 NTSTATUS gensec_child_unseal_packet(struct gensec_security *gensec_security,
 152                                     uint8_t *data, size_t length,
 153                                     const uint8_t *whole_pdu, size_t pdu_length,
 154                                     const DATA_BLOB *sig)
 155 {
 156         if (gensec_security->child_security == NULL) {
 157                 return NT_STATUS_INVALID_PARAMETER;
 158         }
 159
 160         return gensec_unseal_packet(gensec_security->child_security,
 161                                     data, length,
 162                                     whole_pdu, pdu_length,
 163                                     sig);
 164 }
 165
 166 NTSTATUS gensec_child_check_packet(struct gensec_security *gensec_security,
 167                                    const uint8_t *data, size_t length,
 168                                    const uint8_t *whole_pdu, size_t pdu_length,
 169                                    const DATA_BLOB *sig)
 170 {
 171         if (gensec_security->child_security == NULL) {
 172                 return NT_STATUS_INVALID_PARAMETER;
 173         }
 174
 175         return gensec_check_packet(gensec_security->child_security,
 176                                    data, length,
 177                                    whole_pdu, pdu_length,
 178                                    sig);
 179 }
 180
 181 NTSTATUS gensec_child_seal_packet(struct gensec_security *gensec_security,
 182                                   TALLOC_CTX *mem_ctx,
 183                                   uint8_t *data, size_t length,
 184                                   const uint8_t *whole_pdu, size_t pdu_length,
 185                                   DATA_BLOB *sig)
 186 {
 187         if (gensec_security->child_security == NULL) {
 188                 return NT_STATUS_INVALID_PARAMETER;
 189         }
 190
 191         return gensec_seal_packet(gensec_security->child_security,
 192                                   mem_ctx,
 193                                   data, length,
 194                                   whole_pdu, pdu_length,
 195                                   sig);
 196 }
 197
 198 NTSTATUS gensec_child_sign_packet(struct gensec_security *gensec_security,
 199                                   TALLOC_CTX *mem_ctx,
 200                                   const uint8_t *data, size_t length,
 201                                   const uint8_t *whole_pdu, size_t pdu_length,
 202                                   DATA_BLOB *sig)
 203 {
 204         if (gensec_security->child_security == NULL) {
 205                 return NT_STATUS_INVALID_PARAMETER;
 206         }
 207
 208         return gensec_sign_packet(gensec_security->child_security,
 209                                   mem_ctx,
 210                                   data, length,
 211                                   whole_pdu, pdu_length,
 212                                   sig);
 213 }
 214
 215 NTSTATUS gensec_child_wrap(struct gensec_security *gensec_security,
 216                            TALLOC_CTX *mem_ctx,
 217                            const DATA_BLOB *in,
 218                            DATA_BLOB *out)
 219 {
 220         if (gensec_security->child_security == NULL) {
 221                 return NT_STATUS_INVALID_PARAMETER;
 222         }
 223
 224         return gensec_wrap(gensec_security->child_security,
 225                            mem_ctx, in, out);
 226 }
 227
 228 NTSTATUS gensec_child_unwrap(struct gensec_security *gensec_security,
 229                              TALLOC_CTX *mem_ctx,
 230                              const DATA_BLOB *in,
 231                              DATA_BLOB *out)
 232 {
 233         if (gensec_security->child_security == NULL) {
 234                 return NT_STATUS_INVALID_PARAMETER;
 235         }
 236
 237         return gensec_unwrap(gensec_security->child_security,
 238                              mem_ctx, in, out);
 239 }
 240
 241 size_t gensec_child_sig_size(struct gensec_security *gensec_security,
 242                              size_t data_size)
 243 {
 244         if (gensec_security->child_security == NULL) {
 245                 return 0;
 246         }
 247
 248         return gensec_sig_size(gensec_security->child_security, data_size);
 249 }
 250
 251 size_t gensec_child_max_input_size(struct gensec_security *gensec_security)
 252 {
 253         if (gensec_security->child_security == NULL) {
 254                 return 0;
 255         }
 256
 257         return gensec_max_input_size(gensec_security->child_security);
 258 }
 259
 260 size_t gensec_child_max_wrapped_size(struct gensec_security *gensec_security)
 261 {
 262         if (gensec_security->child_security == NULL) {
 263                 return 0;
 264         }
 265
 266         return gensec_max_wrapped_size(gensec_security->child_security);
 267 }
 268
 269 NTSTATUS gensec_child_session_key(struct gensec_security *gensec_security,
 270                                   TALLOC_CTX *mem_ctx,
 271                                   DATA_BLOB *session_key)
 272 {
 273         if (gensec_security->child_security == NULL) {
 274                 return NT_STATUS_INVALID_PARAMETER;
 275         }
 276
 277         return gensec_session_key(gensec_security->child_security,
 278                                   mem_ctx,
 279                                   session_key);
 280 }
 281
 282 NTSTATUS gensec_child_session_info(struct gensec_security *gensec_security,
 283                                    TALLOC_CTX *mem_ctx,
 284                                    struct auth_session_info **session_info)
 285 {
 286         if (gensec_security->child_security == NULL) {
 287                 return NT_STATUS_INVALID_PARAMETER;
 288         }
 289
 290         return gensec_session_info(gensec_security->child_security,
 291                                    mem_ctx,
 292                                    session_info);
 293 }
 294
 295 NTTIME gensec_child_expire_time(struct gensec_security *gensec_security)
 296 {
 297         if (gensec_security->child_security == NULL) {
 298                 return GENSEC_EXPIRE_TIME_INFINITY;
 299         }
 300
 301         return gensec_expire_time(gensec_security->child_security);
 302 }
 303
 304 const char *gensec_child_final_auth_type(struct gensec_security *gensec_security)
 305 {
 306         if (gensec_security->child_security == NULL) {
 307                 return "NONE";
 308         }
 309
 310         return gensec_final_auth_type(gensec_security->child_security);
 311 }