www.project-moonshot.org Git - mech_eap.orig/blob - accept_sec_context.c

   1 /*
   2  * Copyright (c) 2010, JANET(UK)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of JANET(UK) nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "gssapiP_eap.h"
  34
  35 #define EAP_MAX_METHODS 8
  36
  37 #define EAP_TTLS_AUTH_PAP 1
  38 #define EAP_TTLS_AUTH_CHAP 2
  39 #define EAP_TTLS_AUTH_MSCHAP 4
  40 #define EAP_TTLS_AUTH_MSCHAPV2 8
  41
  42 #if 1
  43 struct eap_user {
  44         struct {
  45                 int vendor;
  46                 u32 method;
  47         } methods[EAP_MAX_METHODS];
  48         u8 *password;
  49         size_t password_len;
  50         int password_hash; /* whether password is hashed with
  51                             * nt_password_hash() */
  52         int phase2;
  53         int force_version;
  54         int ttls_auth; /* bitfield of
  55                         * EAP_TTLS_AUTH_{PAP,CHAP,MSCHAP,MSCHAPV2} */
  56 };
  57
  58 struct eap_eapol_interface {
  59         /* Lower layer to full authenticator variables */
  60         Boolean eapResp; /* shared with EAPOL Backend Authentication */
  61         struct wpabuf *eapRespData;
  62         Boolean portEnabled;
  63         int retransWhile;
  64         Boolean eapRestart; /* shared with EAPOL Authenticator PAE */
  65         int eapSRTT;
  66         int eapRTTVAR;
  67
  68         /* Full authenticator to lower layer variables */
  69         Boolean eapReq; /* shared with EAPOL Backend Authentication */
  70         Boolean eapNoReq; /* shared with EAPOL Backend Authentication */
  71         Boolean eapSuccess;
  72         Boolean eapFail;
  73         Boolean eapTimeout;
  74         struct wpabuf *eapReqData;
  75         u8 *eapKeyData;
  76         size_t eapKeyDataLen;
  77         Boolean eapKeyAvailable; /* called keyAvailable in IEEE 802.1X-2004 */
  78
  79         /* AAA interface to full authenticator variables */
  80         Boolean aaaEapReq;
  81         Boolean aaaEapNoReq;
  82         Boolean aaaSuccess;
  83         Boolean aaaFail;
  84         struct wpabuf *aaaEapReqData;
  85         u8 *aaaEapKeyData;
  86         size_t aaaEapKeyDataLen;
  87         Boolean aaaEapKeyAvailable;
  88         int aaaMethodTimeout;
  89
  90         /* Full authenticator to AAA interface variables */
  91         Boolean aaaEapResp;
  92         struct wpabuf *aaaEapRespData;
  93         /* aaaIdentity -> eap_get_identity() */
  94         Boolean aaaTimeout;
  95 };
  96
  97 #define eapol_callbacks     SERVER_eapol_callbacks
  98
  99 struct eapol_callbacks {
 100         int (*get_eap_user)(void *ctx, const u8 *identity, size_t identity_len,
 101                             int phase2, struct eap_user *user);
 102         const char * (*get_eap_req_id_text)(void *ctx, size_t *len);
 103 };
 104
 105 #define eap_config          SERVER_eap_config
 106
 107 struct eap_config {
 108         void *ssl_ctx;
 109         void *msg_ctx;
 110         void *eap_sim_db_priv;
 111         Boolean backend_auth;
 112         int eap_server;
 113         u8 *pac_opaque_encr_key;
 114         u8 *eap_fast_a_id;
 115         size_t eap_fast_a_id_len;
 116         char *eap_fast_a_id_info;
 117         int eap_fast_prov;
 118         int pac_key_lifetime;
 119         int pac_key_refresh_time;
 120         int eap_sim_aka_result_ind;
 121         int tnc;
 122         struct wps_context *wps;
 123         const struct wpabuf *assoc_wps_ie;
 124         const u8 *peer_addr;
 125         int fragment_size;
 126 };
 127
 128 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
 129                                    struct eapol_callbacks *eapol_cb,
 130                                    struct eap_config *eap_conf);
 131 void eap_server_sm_deinit(struct eap_sm *sm);
 132 int eap_server_sm_step(struct eap_sm *sm);
 133 void eap_sm_notify_cached(struct eap_sm *sm);
 134 void eap_sm_pending_cb(struct eap_sm *sm);
 135 int eap_sm_method_pending(struct eap_sm *sm);
 136 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len);
 137 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm);
 138
 139 static OM_uint32
 140 initTls(OM_uint32 *minor,
 141         gss_ctx_id_t ctx)
 142 {
 143     struct tls_config tconf;
 144     struct tls_connection_params tparams;
 145
 146     memset(&tconf, 0, sizeof(tconf));
 147     ctx->acceptorCtx.tlsContext = tls_init(&tconf);
 148     if (ctx->acceptorCtx.tlsContext == NULL)
 149         return GSS_S_FAILURE;
 150
 151     memset(&tparams, 0, sizeof(tparams));
 152     tparams.ca_cert = "ca.pem";
 153     tparams.client_cert = "server.pem";
 154     tparams.private_key = "server-key.pem";
 155
 156     if (tls_global_set_params(ctx->acceptorCtx.tlsContext, &tparams)) {
 157         return GSS_S_FAILURE;
 158     }
 159
 160     if (tls_global_set_verify(ctx->acceptorCtx.tlsContext, 0)) {
 161         return GSS_S_FAILURE;
 162     }
 163
 164     return GSS_S_COMPLETE;
 165 }
 166
 167 static int
 168 serverGetEapUser(void *ctx,
 169                  const unsigned char *identity,
 170                  size_t identityLength,
 171                  int phase2,
 172                  struct eap_user *user)
 173 {
 174     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
 175     OM_uint32 major, minor;
 176     gss_buffer_desc buf;
 177
 178     memset(user, 0, sizeof(*user));
 179
 180     buf.length = identityLength;
 181     buf.value = (void *)identity;
 182
 183     if (phase2 == 0) {
 184         user->methods[0].vendor = EAP_VENDOR_IETF;
 185         user->methods[0].method = EAP_TYPE_PEAP;
 186         return 0;
 187     }
 188
 189     major = gssEapImportName(&minor, &buf, GSS_C_NT_USER_NAME,
 190                              &gssCtx->initiatorName);
 191     if (GSS_ERROR(major))
 192         return -1;
 193
 194     /*
 195      * OK, obviously there is no real security here, this is simply
 196      * for testing the token exchange; this code will be completely
 197      * replaced with libradsec once that library is available.
 198      */
 199     user->methods[0].vendor = EAP_VENDOR_IETF;
 200     user->methods[0].method = EAP_TYPE_MSCHAPV2;
 201     user->password = (unsigned char *)strdup("");
 202     user->password_len = 0;
 203
 204     return 0;
 205 }
 206
 207 static const char *
 208 serverGetEapReqIdText(void *ctx,
 209                       size_t *len)
 210 {
 211     *len = 0;
 212     return NULL;
 213 }
 214 #endif
 215
 216 static OM_uint32
 217 serverDeriveKey(OM_uint32 *minor,
 218                 gss_ctx_id_t ctx)
 219 {
 220     OM_uint32 major;
 221     krb5_context krbContext;
 222
 223     GSSEAP_KRB_INIT(&krbContext);
 224
 225     /* Cache encryption type derived from selected mechanism OID */
 226     major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &ctx->encryptionType);
 227     if (GSS_ERROR(major))
 228         return major;
 229
 230     if (ctx->encryptionType != ENCTYPE_NULL &&
 231         ctx->acceptorCtx.eapPolInterface->eapKeyAvailable) {
 232         major = gssEapDeriveRFC3961Key(minor,
 233                                        ctx->acceptorCtx.eapPolInterface->eapKeyData,
 234                                        ctx->acceptorCtx.eapPolInterface->eapKeyDataLen,
 235                                        ctx->encryptionType,
 236                                        &ctx->rfc3961Key);
 237         if (GSS_ERROR(major))
 238             return major;
 239     } else {
 240         /*
 241          * draft-howlett-eap-gss says that integrity/confidentialty should
 242          * always be advertised as available, but if we have no keying
 243          * material it seems confusing to the caller to advertise this.
 244          */
 245         ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
 246     }
 247
 248     return GSS_S_COMPLETE;
 249 }
 250
 251 static OM_uint32
 252 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 253                            gss_ctx_id_t ctx,
 254                            gss_cred_id_t cred,
 255                            gss_buffer_t inputToken,
 256                            gss_channel_bindings_t chanBindings,
 257                            gss_buffer_t outputToken)
 258 {
 259     OM_uint32 major, tmpMinor, tmpMajor;
 260     int code;
 261     struct wpabuf respData;
 262     struct eap_config *config = (struct eap_config *)&ctx->acceptorCtx.eapConfig;
 263     static struct eapol_callbacks cb = { serverGetEapUser, serverGetEapReqIdText };
 264
 265     wpabuf_set(&respData, inputToken->value, inputToken->length);
 266     ctx->acceptorCtx.eapPolInterface->eapRespData = &respData;
 267     ctx->acceptorCtx.eapPolInterface->eapResp = TRUE;
 268
 269     if (ctx->acceptorCtx.eap == NULL) {
 270         /* initial context token */
 271         config->eap_server = 1;
 272         config->ssl_ctx = ctx->acceptorCtx.tlsContext;
 273
 274         major = initTls(minor, ctx);
 275         if (GSS_ERROR(major))
 276             goto cleanup;
 277
 278         ctx->acceptorCtx.eap = eap_server_sm_init(ctx, &cb, config);
 279         if (ctx->acceptorCtx.eap == NULL) {
 280             major = GSS_S_FAILURE;
 281             goto cleanup;
 282         }
 283     }
 284
 285     if (ctx->acceptorName == GSS_C_NO_NAME && cred->name != GSS_C_NO_NAME) {
 286         major = gss_duplicate_name(minor, cred->name, &ctx->acceptorName);
 287         if (GSS_ERROR(major))
 288             goto cleanup;
 289     }
 290
 291     code = eap_server_sm_step(ctx->acceptorCtx.eap);
 292
 293     if (ctx->acceptorCtx.eapPolInterface->eapReq) {
 294         ctx->acceptorCtx.eapPolInterface->eapReq = 0;
 295         major = GSS_S_CONTINUE_NEEDED;
 296     }
 297
 298     if (ctx->acceptorCtx.eapPolInterface->eapSuccess) {
 299         major = serverDeriveKey(minor, ctx);
 300         if (GSS_ERROR(major))
 301             goto cleanup;
 302
 303         ctx->acceptorCtx.eapPolInterface->eapSuccess = 0;
 304         ctx->state = EAP_STATE_ESTABLISHED;
 305         major = GSS_S_COMPLETE;
 306     } else if (ctx->acceptorCtx.eapPolInterface->eapFail) {
 307         ctx->acceptorCtx.eapPolInterface->eapFail = 0;
 308         major = GSS_S_FAILURE;
 309     } else if (code == 0) {
 310         major = GSS_S_FAILURE;
 311     }
 312
 313     if (ctx->acceptorCtx.eapPolInterface->eapReqData != NULL) {
 314         gss_buffer_desc buf;
 315
 316         buf.length = wpabuf_len(ctx->acceptorCtx.eapPolInterface->eapReqData);
 317         buf.value = (void *)wpabuf_head(ctx->acceptorCtx.eapPolInterface->eapReqData);
 318
 319         tmpMajor = duplicateBuffer(&tmpMinor, &buf, outputToken);
 320         if (GSS_ERROR(tmpMajor)) {
 321             major = tmpMajor;
 322             goto cleanup;
 323         }
 324     }
 325
 326 cleanup:
 327     return major;
 328 }
 329
 330 static OM_uint32
 331 eapGssSmAcceptEstablished(OM_uint32 *minor,
 332                           gss_ctx_id_t ctx,
 333                           gss_cred_id_t cred,
 334                           gss_buffer_t inputToken,
 335                           gss_channel_bindings_t chanBindings,
 336                           gss_buffer_t outputToken)
 337 {
 338     /* Called with already established context */
 339     *minor = EINVAL;
 340     return GSS_S_BAD_STATUS;
 341 }
 342
 343 static struct eap_gss_acceptor_sm {
 344     enum gss_eap_token_type inputTokenType;
 345     enum gss_eap_token_type outputTokenType;
 346     OM_uint32 (*processToken)(OM_uint32 *,
 347                               gss_ctx_id_t,
 348                               gss_cred_id_t,
 349                               gss_buffer_t,
 350                               gss_channel_bindings_t,
 351                               gss_buffer_t);
 352 } eapGssAcceptorSm[] = {
 353     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  eapGssSmAcceptAuthenticate   },
 354     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                         },
 355     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                         },
 356     { TOK_TYPE_GSS_CB,      TOK_TYPE_NONE,     NULL                         },
 357     { TOK_TYPE_NONE,        TOK_TYPE_NONE,     eapGssSmAcceptEstablished    },
 358 };
 359
 360 OM_uint32
 361 gss_accept_sec_context(OM_uint32 *minor,
 362                        gss_ctx_id_t *context_handle,
 363                        gss_cred_id_t cred,
 364                        gss_buffer_t input_token,
 365                        gss_channel_bindings_t input_chan_bindings,
 366                        gss_name_t *src_name,
 367                        gss_OID *mech_type,
 368                        gss_buffer_t output_token,
 369                        OM_uint32 *ret_flags,
 370                        OM_uint32 *time_rec,
 371                        gss_cred_id_t *delegated_cred_handle)
 372 {
 373     OM_uint32 major, tmpMinor;
 374     gss_ctx_id_t ctx = *context_handle;
 375     struct eap_gss_acceptor_sm *sm = NULL;
 376     gss_buffer_desc innerInputToken, innerOutputToken;
 377
 378     *minor = 0;
 379
 380     innerOutputToken.length = 0;
 381     innerOutputToken.value = NULL;
 382
 383     output_token->length = 0;
 384     output_token->value = NULL;
 385
 386     if (cred != GSS_C_NO_CREDENTIAL && !(cred->flags & CRED_FLAG_ACCEPT)) {
 387         return GSS_S_NO_CRED;
 388     }
 389
 390     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 391         return GSS_S_DEFECTIVE_TOKEN;
 392     }
 393
 394     if (ctx == GSS_C_NO_CONTEXT) {
 395         major = gssEapAllocContext(minor, &ctx);
 396         if (GSS_ERROR(major))
 397             return major;
 398
 399         *context_handle = ctx;
 400     }
 401
 402     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 403
 404     sm = &eapGssAcceptorSm[ctx->state];
 405
 406     major = gssEapVerifyToken(minor, ctx, input_token,
 407                               sm->inputTokenType, &innerInputToken);
 408     if (GSS_ERROR(major))
 409         goto cleanup;
 410
 411     do {
 412         major = (sm->processToken)(minor,
 413                                    ctx,
 414                                    cred,
 415                                    &innerInputToken,
 416                                    input_chan_bindings,
 417                                    &innerOutputToken);
 418         if (GSS_ERROR(major))
 419             goto cleanup;
 420     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 421
 422     if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 423         major = gss_duplicate_name(minor, ctx->initiatorName, src_name);
 424         if (GSS_ERROR(major))
 425             goto cleanup;
 426     }
 427     if (mech_type != NULL) {
 428         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 429             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 430     }
 431     if (innerOutputToken.length != 0) {
 432         major = gssEapMakeToken(minor, ctx, &innerOutputToken,
 433                                 sm->outputTokenType, output_token);
 434         if (GSS_ERROR(major))
 435             goto cleanup;
 436     }
 437     if (ret_flags != NULL)
 438         *ret_flags = ctx->gssFlags;
 439     if (time_rec != NULL)
 440         gss_context_time(&tmpMinor, ctx, time_rec);
 441     if (delegated_cred_handle != NULL)
 442         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 443
 444     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 445
 446 cleanup:
 447     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 448
 449     if (GSS_ERROR(major))
 450         gssEapReleaseContext(&tmpMinor, context_handle);
 451
 452     gss_release_buffer(&tmpMinor, &innerOutputToken);
 453
 454     return major;
 455 }