initial TLV refactor
[mech_eap.orig] / init_sec_context.c
index a8561dd..f55aec9 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010, JANET(UK)
+ * Copyright (c) 2011, JANET(UK)
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * SUCH DAMAGE.
  */
 
-#include "gssapiP_eap.h"
-
-#ifdef GSSEAP_ENABLE_REAUTH
-static int
-canReauthP(gss_cred_id_t cred);
+/*
+ * Establish a security context on the initiator (client). These functions
+ * wrap around libeap.
+ */
 
-static OM_uint32
-eapGssSmInitGssReauth(OM_uint32 *minor,
-                      gss_cred_id_t cred,
-                      gss_ctx_id_t ctx,
-                      gss_name_t target,
-                      gss_OID mech,
-                      OM_uint32 reqFlags,
-                      OM_uint32 timeReq,
-                      gss_channel_bindings_t chanBindings,
-                      gss_buffer_t inputToken,
-                      gss_buffer_t outputToken);
-#endif
+#include "gssapiP_eap.h"
 
 static OM_uint32
 policyVariableToFlag(enum eapol_bool_var variable)
@@ -200,7 +188,9 @@ static struct eapol_callbacks gssEapPolicyCallbacks = {
     peerNotifyPending,
 };
 
+#ifdef GSSEAP_DEBUG
 extern int wpa_debug_level;
+#endif
 
 static OM_uint32
 peerConfigInit(OM_uint32 *minor,
@@ -210,7 +200,7 @@ peerConfigInit(OM_uint32 *minor,
     krb5_context krbContext;
     struct eap_peer_config *eapPeerConfig = &ctx->initiatorCtx.eapPeerConfig;
     krb5_error_code code;
-    char *identity;
+    char *identity, *anonymousIdentity;
 
     eapPeerConfig->identity = NULL;
     eapPeerConfig->identity_len = 0;
@@ -222,7 +212,16 @@ peerConfigInit(OM_uint32 *minor,
     GSSEAP_KRB_INIT(&krbContext);
 
     eapPeerConfig->fragment_size = 1024;
+#ifdef GSSEAP_DEBUG
     wpa_debug_level = 0;
+#endif
+
+    assert(cred->name != GSS_C_NO_NAME);
+
+    if ((cred->name->flags & (NAME_FLAG_NAI | NAME_FLAG_SERVICE)) == 0) {
+        *minor = GSSEAP_BAD_INITIATOR_NAME;
+        return GSS_S_BAD_NAME;
+    }
 
     code = krb5_unparse_name(krbContext, cred->name->krbPrincipal, &identity);
     if (code != 0) {
@@ -230,11 +229,18 @@ peerConfigInit(OM_uint32 *minor,
         return GSS_S_FAILURE;
     }
 
+    anonymousIdentity = strchr(identity, '@');
+    if (anonymousIdentity == NULL)
+        anonymousIdentity = "";
+
     eapPeerConfig->identity = (unsigned char *)identity;
     eapPeerConfig->identity_len = strlen(identity);
+    eapPeerConfig->anonymous_identity = (unsigned char *)anonymousIdentity;
+    eapPeerConfig->anonymous_identity_len = strlen(anonymousIdentity);
     eapPeerConfig->password = (unsigned char *)cred->password.value;
     eapPeerConfig->password_len = cred->password.length;
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
@@ -249,61 +255,56 @@ peerConfigFree(OM_uint32 *minor,
 
     krb5_free_unparsed_name(krbContext, (char *)eapPeerConfig->identity);
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
+/*
+ * Mark an initiator context as ready for cryptographic operations
+ */
 static OM_uint32
 initReady(OM_uint32 *minor, gss_ctx_id_t ctx, OM_uint32 reqFlags)
 {
     OM_uint32 major;
     const unsigned char *key;
     size_t keyLength;
-    krb5_enctype encryptionType;
-    int gotKey = 0;
 
-#if 0
+#if 1
     /* XXX actually check for mutual auth */
     if (reqFlags & GSS_C_MUTUAL_FLAG)
         ctx->gssFlags |= GSS_C_MUTUAL_FLAG;
 #endif
 
     /* Cache encryption type derived from selected mechanism OID */
-    major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &encryptionType);
+    major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &ctx->encryptionType);
     if (GSS_ERROR(major))
         return major;
 
-    if (encryptionType != ENCTYPE_NULL &&
-        eap_key_available(ctx->initiatorCtx.eap)) {
-        key = eap_get_eapKeyData(ctx->initiatorCtx.eap, &keyLength);
-
-        if (keyLength >= EAP_EMSK_LEN) {
-            major = gssEapDeriveRfc3961Key(minor,
-                                           &key[EAP_EMSK_LEN / 2],
-                                           EAP_EMSK_LEN / 2,
-                                           encryptionType,
-                                           &ctx->rfc3961Key);
-               if (GSS_ERROR(major))
-                   return major;
-
-            major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
-                                              &ctx->checksumType);
-            if (GSS_ERROR(major))
-                return major;
-            gotKey++;
-        }
+    if (!eap_key_available(ctx->initiatorCtx.eap)) {
+        *minor = GSSEAP_KEY_UNAVAILABLE;
+        return GSS_S_UNAVAILABLE;
     }
 
-    if (gotKey) {
-        ctx->encryptionType = encryptionType;
-    } else {
-        /*
-         * draft-howlett-eap-gss says that integrity/confidentialty should
-         * always be advertised as available, but if we have no keying
-         * material it seems confusing to the caller to advertise this.
-         */
-        ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
+    key = eap_get_eapKeyData(ctx->initiatorCtx.eap, &keyLength);
+
+    if (keyLength < EAP_EMSK_LEN) {
+        *minor = GSSEAP_KEY_TOO_SHORT;
+        return GSS_S_UNAVAILABLE;
     }
 
+    major = gssEapDeriveRfc3961Key(minor,
+                                   &key[EAP_EMSK_LEN / 2],
+                                   EAP_EMSK_LEN / 2,
+                                   ctx->encryptionType,
+                                   &ctx->rfc3961Key);
+       if (GSS_ERROR(major))
+           return major;
+
+    major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
+                                      &ctx->checksumType);
+    if (GSS_ERROR(major))
+        return major;
+
     major = sequenceInit(minor,
                          &ctx->seqState,
                          ctx->recvSeq,
@@ -313,6 +314,7 @@ initReady(OM_uint32 *minor, gss_ctx_id_t ctx, OM_uint32 reqFlags)
     if (GSS_ERROR(major))
         return major;
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
@@ -325,8 +327,7 @@ initBegin(OM_uint32 *minor,
           OM_uint32 reqFlags,
           OM_uint32 timeReq,
           gss_channel_bindings_t chanBindings,
-          gss_buffer_t inputToken,
-          gss_buffer_t outputToken)
+          gss_buffer_t inputToken)
 {
     OM_uint32 major;
 
@@ -339,33 +340,158 @@ initBegin(OM_uint32 *minor,
     else
         ctx->expiryTime = time(NULL) + timeReq;
 
+    /*
+     * The credential mutex protects its name, however we need to
+     * explicitly lock the acceptor name (unlikely as it may be
+     * that it has attributes set on it).
+     */
     major = gssEapDuplicateName(minor, cred->name, &ctx->initiatorName);
     if (GSS_ERROR(major))
         return major;
 
+    GSSEAP_MUTEX_LOCK(&target->mutex);
+
     major = gssEapDuplicateName(minor, target, &ctx->acceptorName);
-    if (GSS_ERROR(major))
+    if (GSS_ERROR(major)) {
+        GSSEAP_MUTEX_UNLOCK(&target->mutex);
         return major;
+    }
 
-    if (mech == GSS_C_NULL_OID || oidEqual(mech, GSS_EAP_MECHANISM)) {
+    GSSEAP_MUTEX_UNLOCK(&target->mutex);
+
+    if (mech == GSS_C_NULL_OID) {
         major = gssEapDefaultMech(minor, &ctx->mechanismUsed);
     } else if (gssEapIsConcreteMechanismOid(mech)) {
         if (!gssEapInternalizeOid(mech, &ctx->mechanismUsed))
             major = duplicateOid(minor, mech, &ctx->mechanismUsed);
     } else {
         major = GSS_S_BAD_MECH;
+        *minor = GSSEAP_WRONG_MECH;
     }
     if (GSS_ERROR(major))
         return major;
 
     /* If credentials were provided, check they're usable with this mech */
-    if (!gssEapCredAvailable(cred, ctx->mechanismUsed))
+    if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
+        *minor = GSSEAP_CRED_MECH_MISMATCH;
         return GSS_S_BAD_MECH;
+    }
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
 static OM_uint32
+eapGssSmInitError(OM_uint32 *minor,
+                  gss_cred_id_t cred,
+                  gss_ctx_id_t ctx,
+                  gss_name_t target,
+                  gss_OID mech,
+                  OM_uint32 reqFlags,
+                  OM_uint32 timeReq,
+                  gss_channel_bindings_t chanBindings,
+                  gss_buffer_t inputToken,
+                  gss_buffer_t outputToken)
+{
+    OM_uint32 major;
+    unsigned char *p;
+
+    if (inputToken->length < 8) {
+        *minor = GSSEAP_TOK_TRUNC;
+        return GSS_S_DEFECTIVE_TOKEN;
+    }
+
+    p = (unsigned char *)inputToken->value;
+
+    major = load_uint32_be(&p[0]);
+    *minor = ERROR_TABLE_BASE_eapg + load_uint32_be(&p[4]);
+
+    if (!GSS_ERROR(major) || !IS_WIRE_ERROR(*minor)) {
+        major = GSS_S_FAILURE;
+        *minor = GSSEAP_BAD_ERROR_TOKEN;
+    }
+
+    assert(GSS_ERROR(major));
+
+    return major;
+}
+
+#ifdef GSSEAP_ENABLE_REAUTH
+static OM_uint32
+eapGssSmInitGssReauth(OM_uint32 *minor,
+                      gss_cred_id_t cred,
+                      gss_ctx_id_t ctx,
+                      gss_name_t target,
+                      gss_OID mech,
+                      OM_uint32 reqFlags,
+                      OM_uint32 timeReq,
+                      gss_channel_bindings_t chanBindings,
+                      gss_buffer_t inputToken,
+                      gss_buffer_t outputToken)
+{
+    OM_uint32 major, tmpMinor;
+    gss_name_t mechTarget = GSS_C_NO_NAME;
+    gss_OID actualMech = GSS_C_NO_OID;
+    OM_uint32 gssFlags, timeRec;
+
+    assert(cred != GSS_C_NO_CREDENTIAL);
+
+    if (ctx->state == GSSEAP_STATE_INITIAL) {
+        if (!gssEapCanReauthP(cred, target, timeReq))
+            return GSS_S_CONTINUE_NEEDED;
+
+        major = initBegin(minor, cred, ctx, target, mech,
+                          reqFlags, timeReq, chanBindings,
+                          inputToken);
+        if (GSS_ERROR(major))
+            goto cleanup;
+
+        ctx->flags |= CTX_FLAG_KRB_REAUTH;
+    } else if ((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0) {
+        major = GSS_S_DEFECTIVE_TOKEN;
+        *minor = GSSEAP_WRONG_ITOK;
+        goto cleanup;
+    }
+
+    major = gssEapMechToGlueName(minor, target, &mechTarget);
+    if (GSS_ERROR(major))
+        goto cleanup;
+
+    major = gssInitSecContext(minor,
+                              cred->krbCred,
+                              &ctx->kerberosCtx,
+                              mechTarget,
+                              (gss_OID)gss_mech_krb5,
+                              reqFlags,
+                              timeReq,
+                              chanBindings,
+                              inputToken,
+                              &actualMech,
+                              outputToken,
+                              &gssFlags,
+                              &timeRec);
+    if (GSS_ERROR(major))
+        goto cleanup;
+
+    ctx->gssFlags = gssFlags;
+
+    if (major == GSS_S_COMPLETE) {
+        major = gssEapReauthComplete(minor, ctx, cred, actualMech, timeRec);
+        if (GSS_ERROR(major))
+            goto cleanup;
+        ctx->state = GSSEAP_STATE_NEGO_EXT; /* skip */
+    } else {
+        major = GSS_S_COMPLETE; /* advance state */
+    }
+
+cleanup:
+    gssReleaseName(&tmpMinor, &mechTarget);
+
+    return major;
+}
+#endif /* GSSEAP_ENABLE_REAUTH */
+
+static OM_uint32
 eapGssSmInitIdentity(OM_uint32 *minor,
                      gss_cred_id_t cred,
                      gss_ctx_id_t ctx,
@@ -380,19 +506,25 @@ eapGssSmInitIdentity(OM_uint32 *minor,
     OM_uint32 major;
     int initialContextToken;
 
+    assert((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
+
     initialContextToken = (inputToken->length == 0);
-    if (!initialContextToken)
+    if (!initialContextToken) {
+        *minor = GSSEAP_WRONG_SIZE;
         return GSS_S_DEFECTIVE_TOKEN;
+    }
 
     major = initBegin(minor, cred, ctx, target, mech,
                       reqFlags, timeReq, chanBindings,
-                      inputToken, outputToken);
+                      inputToken);
     if (GSS_ERROR(major))
         return major;
 
-    ctx->state = EAP_STATE_AUTHENTICATE;
+    outputToken->length = 0;
+    outputToken->value = NULL;
 
-    return GSS_S_CONTINUE_NEEDED;
+    *minor = 0;
+    return GSS_S_COMPLETE; /* advance state */
 }
 
 static struct wpabuf emptyWpaBuffer;
@@ -415,6 +547,8 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
     struct wpabuf *resp = NULL;
     int initialContextToken;
 
+    *minor = 0;
+
     initialContextToken = (inputToken == GSS_C_NO_BUFFER ||
                            inputToken->length == 0);
 
@@ -433,6 +567,7 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
                                                  &eapConfig);
         if (ctx->initiatorCtx.eap == NULL) {
             major = GSS_S_FAILURE;
+            *minor = GSSEAP_PEER_SM_INIT_FAILURE;
             goto cleanup;
         }
 
@@ -444,28 +579,27 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
     wpabuf_set(&ctx->initiatorCtx.reqData,
                inputToken->value, inputToken->length);
 
-    major = GSS_S_CONTINUE_NEEDED;
-
     code = eap_peer_sm_step(ctx->initiatorCtx.eap);
     if (ctx->flags & CTX_FLAG_EAP_RESP) {
         ctx->flags &= ~(CTX_FLAG_EAP_RESP);
 
         resp = eap_get_eapRespData(ctx->initiatorCtx.eap);
+        major = GSS_S_CONTINUE_NEEDED;
     } else if (ctx->flags & CTX_FLAG_EAP_SUCCESS) {
         major = initReady(minor, ctx, reqFlags);
         if (GSS_ERROR(major))
             goto cleanup;
 
         ctx->flags &= ~(CTX_FLAG_EAP_SUCCESS);
-        major = GSS_S_CONTINUE_NEEDED;
-        ctx->state = EAP_STATE_EXTENSIONS_REQ;
+        major = GSS_S_COMPLETE; /* advance state */
     } else if (ctx->flags & CTX_FLAG_EAP_FAIL) {
         major = GSS_S_DEFECTIVE_CREDENTIAL;
+        *minor = GSSEAP_PEER_AUTH_FAILURE;
     } else if (code == 0 && initialContextToken) {
-        resp = &emptyWpaBuffer;
         major = GSS_S_CONTINUE_NEEDED;
     } else {
         major = GSS_S_DEFECTIVE_TOKEN;
+        *minor = GSSEAP_PEER_BAD_MESSAGE;
     }
 
 cleanup:
@@ -473,7 +607,7 @@ cleanup:
         OM_uint32 tmpMajor;
         gss_buffer_desc respBuf;
 
-        assert(major == GSS_S_CONTINUE_NEEDED);
+        assert(!GSS_ERROR(major));
 
         respBuf.length = wpabuf_len(resp);
         respBuf.value = (void *)wpabuf_head(resp);
@@ -492,85 +626,37 @@ cleanup:
 }
 
 static OM_uint32
-initGssChannelBindings(OM_uint32 *minor,
-                       gss_ctx_id_t ctx,
-                       gss_channel_bindings_t chanBindings,
-                       gss_buffer_t outputToken)
+eapGssSmInitGssChannelBindings(OM_uint32 *minor,
+                               gss_cred_id_t cred,
+                               gss_ctx_id_t ctx,
+                               gss_name_t target,
+                               gss_OID mech,
+                               OM_uint32 reqFlags,
+                               OM_uint32 timeReq,
+                               gss_channel_bindings_t chanBindings,
+                               gss_buffer_t inputToken,
+                               gss_buffer_t outputToken)
 {
     OM_uint32 major;
     gss_buffer_desc buffer = GSS_C_EMPTY_BUFFER;
 
-
     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS)
         buffer = chanBindings->application_data;
 
     major = gssEapWrap(minor, ctx, TRUE, GSS_C_QOP_DEFAULT,
                        &buffer, NULL, outputToken);
     if (GSS_ERROR(major))
-        return major;                       
-
-    return GSS_S_CONTINUE_NEEDED;
-}
-
-static OM_uint32
-eapGssSmInitExtensionsReq(OM_uint32 *minor,
-                          gss_cred_id_t cred,
-                          gss_ctx_id_t ctx,
-                          gss_name_t target,
-                          gss_OID mech,
-                          OM_uint32 reqFlags,
-                          OM_uint32 timeReq,
-                          gss_channel_bindings_t chanBindings,
-                          gss_buffer_t inputToken,
-                          gss_buffer_t outputToken)
-{
-    OM_uint32 major, tmpMinor;
-    gss_buffer_desc cbToken = GSS_C_EMPTY_BUFFER;
-
-    major = initGssChannelBindings(minor, ctx, chanBindings, &cbToken);
-    if (GSS_ERROR(major))
-        return major;
-
-    ctx->state = EAP_STATE_EXTENSIONS_RESP;
-
-    major = duplicateBuffer(minor, &cbToken, outputToken);
-    if (GSS_ERROR(major)) {
-        gss_release_buffer(&tmpMinor, &cbToken);
         return major;
-    }
 
-    gss_release_buffer(&tmpMinor, &cbToken);
+    assert(outputToken->value != NULL);
 
+    *minor = 0;
     return GSS_S_CONTINUE_NEEDED;
 }
 
-static OM_uint32
-eapGssSmInitExtensionsResp(OM_uint32 *minor,
-                           gss_cred_id_t cred,
-                           gss_ctx_id_t ctx,
-                           gss_name_t target,
-                           gss_OID mech,
-                           OM_uint32 reqFlags,
-                           OM_uint32 timeReq,
-                           gss_channel_bindings_t chanBindings,
-                           gss_buffer_t inputToken,
-                           gss_buffer_t outputToken)
-{
 #ifdef GSSEAP_ENABLE_REAUTH
-    OM_uint32 major;
-
-    major = gssEapStoreReauthCreds(minor, ctx, cred, inputToken);
-    if (GSS_ERROR(major))
-        return major;
-#endif
-
-    ctx->state = EAP_STATE_ESTABLISHED;
-
-    return GSS_S_COMPLETE;
-}
-
 static OM_uint32
-eapGssSmInitEstablished(OM_uint32 *minor,
+eapGssSmInitReauthCreds(OM_uint32 *minor,
                         gss_cred_id_t cred,
                         gss_ctx_id_t ctx,
                         gss_name_t target,
@@ -581,33 +667,96 @@ eapGssSmInitEstablished(OM_uint32 *minor,
                         gss_buffer_t inputToken,
                         gss_buffer_t outputToken)
 {
-    /* Called with already established context */
-    *minor = EINVAL;
-    return GSS_S_BAD_STATUS;
+    OM_uint32 major;
+
+    major = gssEapStoreReauthCreds(minor, ctx, cred, inputToken);
+    if (GSS_ERROR(major))
+        return major;
+
+    *minor = 0;
+    return GSS_S_CONTINUE_NEEDED;
 }
+#endif /* GSSEAP_ENABLE_REAUTH */
 
-static struct gss_eap_initiator_sm {
-    enum gss_eap_token_type inputTokenType;
-    enum gss_eap_token_type outputTokenType;
-    OM_uint32 (*processToken)(OM_uint32 *,
-                              gss_cred_id_t,
-                              gss_ctx_id_t,
-                              gss_name_t,
-                              gss_OID,
-                              OM_uint32,
-                              OM_uint32,
-                              gss_channel_bindings_t,
-                              gss_buffer_t,
-                              gss_buffer_t);
-} eapGssInitiatorSm[] = {
-    { TOK_TYPE_NONE,    TOK_TYPE_EAP_RESP,      eapGssSmInitIdentity            },
-    { TOK_TYPE_EAP_REQ, TOK_TYPE_EAP_RESP,      eapGssSmInitAuthenticate        },
-    { TOK_TYPE_NONE,    TOK_TYPE_EXT_REQ,       eapGssSmInitExtensionsReq       },
-    { TOK_TYPE_EXT_RESP,TOK_TYPE_NONE,          eapGssSmInitExtensionsResp      },
-    { TOK_TYPE_NONE,    TOK_TYPE_NONE,          eapGssSmInitEstablished         },
+static OM_uint32
+eapGssSmInitNegoExtFinished(OM_uint32 *minor,
+                            gss_cred_id_t cred,
+                            gss_ctx_id_t ctx,
+                            gss_name_t target,
+                            gss_OID mech,
+                            OM_uint32 reqFlags,
+                            OM_uint32 timeReq,
+                            gss_channel_bindings_t chanBindings,
+                            gss_buffer_t inputToken,
+                            gss_buffer_t outputToken)
+{
+    *minor = 0;
+    return GSS_S_COMPLETE; /* advance state */
+}
+
+static struct gss_eap_sm eapGssInitiatorSm[] = {
+    {
+        ITOK_TYPE_CONTEXT_ERR,
+        ITOK_TYPE_NONE,
+        GSSEAP_STATE_ALL,
+        1, /* critical */
+        0, /* required */
+        eapGssSmInitError,
+    },
 #ifdef GSSEAP_ENABLE_REAUTH
-    { TOK_TYPE_GSS_REAUTH, TOK_TYPE_GSS_REAUTH, eapGssSmInitGssReauth           },
+    {
+        ITOK_TYPE_REAUTH_RESP,
+        ITOK_TYPE_REAUTH_REQ,
+        GSSEAP_STATE_INITIAL | GSSEAP_STATE_AUTHENTICATE,
+        0, /* critical */
+        0, /* required */
+        eapGssSmInitGssReauth,
+    },
 #endif
+    /* first-leg extensions go here, they should return GSS_S_CONTINUE_NEEDED */
+    {
+        ITOK_TYPE_NONE,
+        ITOK_TYPE_NONE,
+        GSSEAP_STATE_INITIAL,
+        1, /* critical */
+        1, /* required */
+        eapGssSmInitIdentity,
+    },
+    {
+        ITOK_TYPE_EAP_REQ,
+        ITOK_TYPE_EAP_RESP,
+        GSSEAP_STATE_AUTHENTICATE,
+        1, /* critical */
+        1, /* required */
+        eapGssSmInitAuthenticate,
+    },
+    {
+        ITOK_TYPE_NONE,
+        ITOK_TYPE_GSS_CHANNEL_BINDINGS,
+        GSSEAP_STATE_NEGO_EXT,
+        1, /* critical */
+        1, /* required */
+        eapGssSmInitGssChannelBindings,
+    },
+#ifdef GSSEAP_ENABLE_REAUTH
+    {
+        ITOK_TYPE_REAUTH_CREDS,
+        ITOK_TYPE_NONE,
+        GSSEAP_STATE_NEGO_EXT,
+        0, /* critical */
+        0, /* required */
+        eapGssSmInitReauthCreds,
+    },
+#endif
+    /* other extensions go here */
+    {
+        ITOK_TYPE_NONE,
+        ITOK_TYPE_NONE,
+        GSSEAP_STATE_NEGO_EXT,
+        1, /* critical */
+        1, /* required */
+        eapGssSmInitNegoExtFinished
+    }
 };
 
 OM_uint32
@@ -625,14 +774,9 @@ gss_init_sec_context(OM_uint32 *minor,
                      OM_uint32 *ret_flags,
                      OM_uint32 *time_rec)
 {
-    OM_uint32 major;
-    OM_uint32 tmpMajor, tmpMinor;
+    OM_uint32 major, tmpMinor;
     gss_ctx_id_t ctx = *context_handle;
-    struct gss_eap_initiator_sm *sm = NULL;
-    gss_buffer_desc innerInputToken;
-    gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
-    enum gss_eap_token_type tokType;
-    gss_cred_id_t defaultCred = GSS_C_NO_CREDENTIAL;
+    int initialContextToken = 0;
 
     *minor = 0;
 
@@ -641,187 +785,82 @@ gss_init_sec_context(OM_uint32 *minor,
 
     if (ctx == GSS_C_NO_CONTEXT) {
         if (input_token != GSS_C_NO_BUFFER && input_token->length != 0) {
+            *minor = GSSEAP_WRONG_SIZE;
             return GSS_S_DEFECTIVE_TOKEN;
         }
 
         major = gssEapAllocContext(minor, &ctx);
         if (GSS_ERROR(major))
-            goto cleanup;
+            return major;
 
         ctx->flags |= CTX_FLAG_INITIATOR;
 
-#ifdef GSSEAP_ENABLE_REAUTH
-        if (canReauthP(cred))
-            ctx->state = EAP_STATE_KRB_REAUTH_GSS;
-#endif
-
+        initialContextToken = 1;
         *context_handle = ctx;
     }
 
-    if (cred != GSS_C_NO_CREDENTIAL) {
-        if ((cred->flags & CRED_FLAG_INITIATE) == 0) {
-            major = GSS_S_NO_CRED;
-            goto cleanup;
-        }
-    } else {
-        if (ctx->initiatorCtx.defaultCred == GSS_C_NO_CREDENTIAL) {
+    GSSEAP_MUTEX_LOCK(&ctx->mutex);
+
+    if (cred == GSS_C_NO_CREDENTIAL) {
+        if (ctx->defaultCred == GSS_C_NO_CREDENTIAL) {
             major = gssEapAcquireCred(minor,
                                       GSS_C_NO_NAME,
                                       GSS_C_NO_BUFFER,
                                       time_req,
                                       GSS_C_NO_OID_SET,
                                       GSS_C_INITIATE,
-                                      &defaultCred,
+                                      &ctx->defaultCred,
                                       NULL,
                                       NULL);
             if (GSS_ERROR(major))
                 goto cleanup;
         }
 
-        cred = ctx->initiatorCtx.defaultCred;
+        cred = ctx->defaultCred;
     }
 
-    GSSEAP_MUTEX_LOCK(&ctx->mutex);
-
-    sm = &eapGssInitiatorSm[ctx->state];
+    GSSEAP_MUTEX_LOCK(&cred->mutex);
 
-    if (input_token != GSS_C_NO_BUFFER) {
-        major = gssEapVerifyToken(minor, ctx, input_token,
-                                  &tokType, &innerInputToken);
-        if (GSS_ERROR(major))
-            goto cleanup;
 
-        if (tokType != sm->inputTokenType) {
-            major = GSS_S_DEFECTIVE_TOKEN;
-            goto cleanup;
-        }
-    } else {
-        innerInputToken.length = 0;
-        innerInputToken.value = NULL;
+    if ((cred->flags & CRED_FLAG_INITIATE) == 0) {
+        major = GSS_S_NO_CRED;
+        *minor = GSSEAP_CRED_USAGE_MISMATCH;
+        goto cleanup;
     }
 
-    /*
-     * Advance through state machine whilst empty tokens are emitted and
-     * the status is not GSS_S_COMPLETE or an error status.
-     */
-    do {
-        sm = &eapGssInitiatorSm[ctx->state];
-
-        major = (sm->processToken)(minor,
-                                   cred,
-                                   ctx,
-                                   target_name,
-                                   mech_type,
-                                   req_flags,
-                                   time_req,
-                                   input_chan_bindings,
-                                   &innerInputToken,
-                                   &innerOutputToken);
-        if (GSS_ERROR(major))
-            goto cleanup;
-    } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.value == NULL);
+    major = gssEapSmStep(minor,
+                         cred,
+                         ctx,
+                         target_name,
+                         mech_type,
+                         req_flags,
+                         time_req,
+                         input_chan_bindings,
+                         input_token,
+                         output_token,
+                         eapGssInitiatorSm,
+                         sizeof(eapGssInitiatorSm) / sizeof(eapGssInitiatorSm[0]));
+    if (GSS_ERROR(major))
+        goto cleanup;
 
     if (actual_mech_type != NULL) {
         if (!gssEapInternalizeOid(ctx->mechanismUsed, actual_mech_type))
             duplicateOid(&tmpMinor, ctx->mechanismUsed, actual_mech_type);
     }
-    if (innerOutputToken.value != NULL) {
-        tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
-                                   sm->outputTokenType, output_token);
-        if (GSS_ERROR(tmpMajor)) {
-            major = tmpMajor;
-            *minor = tmpMinor;
-            goto cleanup;
-        }
-    }
     if (ret_flags != NULL)
         *ret_flags = ctx->gssFlags;
     if (time_rec != NULL)
         gssEapContextTime(&tmpMinor, ctx, time_rec);
 
-    assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
+    assert(ctx->state == GSSEAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 
 cleanup:
+    if (cred != GSS_C_NO_CREDENTIAL)
+        GSSEAP_MUTEX_UNLOCK(&cred->mutex);
     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 
     if (GSS_ERROR(major))
         gssEapReleaseContext(&tmpMinor, context_handle);
 
-    gss_release_buffer(&tmpMinor, &innerOutputToken);
-
     return major;
 }
-
-#ifdef GSSEAP_ENABLE_REAUTH
-static int
-canReauthP(gss_cred_id_t cred)
-{
-    return (cred != GSS_C_NO_CREDENTIAL &&
-            cred->krbCred != GSS_C_NO_CREDENTIAL &&
-            cred->expiryTime > time(NULL));
-}
-
-static OM_uint32
-eapGssSmInitGssReauth(OM_uint32 *minor,
-                      gss_cred_id_t cred,
-                      gss_ctx_id_t ctx,
-                      gss_name_t target,
-                      gss_OID mech,
-                      OM_uint32 reqFlags,
-                      OM_uint32 timeReq,
-                      gss_channel_bindings_t chanBindings,
-                      gss_buffer_t inputToken,
-                      gss_buffer_t outputToken)
-{
-    OM_uint32 major, tmpMinor;
-    gss_name_t mechTarget = GSS_C_NO_NAME;
-    gss_OID actualMech = GSS_C_NO_OID;
-    OM_uint32 gssFlags, timeRec;
-
-    assert(cred != GSS_C_NO_CREDENTIAL);
-
-    ctx->flags |= CTX_FLAG_KRB_REAUTH_GSS;
-
-    if (inputToken->length == 0) {
-        major = initBegin(minor, cred, ctx, target, mech,
-                          reqFlags, timeReq, chanBindings,
-                          inputToken, outputToken);
-        if (GSS_ERROR(major))
-            goto cleanup;
-    }
-
-    major = gssEapMechToGlueName(minor, target, &mechTarget);
-    if (GSS_ERROR(major))
-        goto cleanup;
-
-    major = gssInitSecContext(minor,
-                              cred->krbCred,
-                              &ctx->kerberosCtx,
-                              mechTarget,
-                              (gss_OID)gss_mech_krb5,
-                              reqFlags, /* | GSS_C_DCE_STYLE, */
-                              timeReq,
-                              chanBindings,
-                              inputToken,
-                              &actualMech,
-                              outputToken,
-                              &gssFlags,
-                              &timeRec);
-    if (GSS_ERROR(major))
-        goto cleanup;
-
-    ctx->gssFlags = gssFlags;
-
-    if (major == GSS_S_COMPLETE) {
-        major = gssEapReauthComplete(minor, ctx, cred, actualMech, timeRec);
-        if (GSS_ERROR(major))
-            goto cleanup;
-        ctx->state = EAP_STATE_ESTABLISHED;
-    }
-
-cleanup:
-    gssReleaseName(&tmpMinor, &mechTarget);
-
-    return major;
-}
-#endif /* GSSEAP_ENABLE_REAUTH */