Note that /etc/gss/mech is not implementation-specific
[mech_eap.orig] / init_sec_context.c
index e3b4d63..ae0a65c 100644 (file)
  * SUCH DAMAGE.
  */
 
+/*
+ * Establish a security context on the initiator (client). These functions
+ * wrap around libeap.
+ */
+
 #include "gssapiP_eap.h"
 
 #ifdef GSSEAP_ENABLE_REAUTH
-static int
-canReauthP(gss_cred_id_t cred);
-
 static OM_uint32
 eapGssSmInitGssReauth(OM_uint32 *minor,
                       gss_cred_id_t cred,
@@ -200,7 +202,9 @@ static struct eapol_callbacks gssEapPolicyCallbacks = {
     peerNotifyPending,
 };
 
+#ifdef GSSEAP_DEBUG
 extern int wpa_debug_level;
+#endif
 
 static OM_uint32
 peerConfigInit(OM_uint32 *minor,
@@ -212,10 +216,26 @@ peerConfigInit(OM_uint32 *minor,
     krb5_error_code code;
     char *identity;
 
+    eapPeerConfig->identity = NULL;
+    eapPeerConfig->identity_len = 0;
+    eapPeerConfig->password = NULL;
+    eapPeerConfig->password_len = 0;
+
+    assert(cred != GSS_C_NO_CREDENTIAL);
+
     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) {
@@ -228,6 +248,7 @@ peerConfigInit(OM_uint32 *minor,
     eapPeerConfig->password = (unsigned char *)cred->password.value;
     eapPeerConfig->password_len = cred->password.length;
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
@@ -242,55 +263,56 @@ 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)
+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 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,
@@ -300,6 +322,7 @@ initReady(OM_uint32 *minor, gss_ctx_id_t ctx)
     if (GSS_ERROR(major))
         return major;
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
@@ -317,38 +340,53 @@ initBegin(OM_uint32 *minor,
 {
     OM_uint32 major;
 
-    if (cred != GSS_C_NO_CREDENTIAL && cred->expiryTime)
+    assert(cred != GSS_C_NO_CREDENTIAL);
+
+    if (cred->expiryTime)
         ctx->expiryTime = cred->expiryTime;
     else if (timeReq == 0 || timeReq == GSS_C_INDEFINITE)
         ctx->expiryTime = 0;
     else
         ctx->expiryTime = time(NULL) + timeReq;
 
-    if (cred != GSS_C_NO_CREDENTIAL) {
-        major = gssEapDuplicateName(minor, cred->name, &ctx->initiatorName);
-        if (GSS_ERROR(major))
-            return major;
-    }
+    /*
+     * 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;
+    }
+
+    GSSEAP_MUTEX_UNLOCK(&target->mutex);
 
-    if (mech == GSS_C_NULL_OID || oidEqual(mech, GSS_EAP_MECHANISM)) {
+    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;
 }
 
@@ -368,8 +406,10 @@ eapGssSmInitIdentity(OM_uint32 *minor,
     int initialContextToken;
 
     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,
@@ -377,8 +417,9 @@ eapGssSmInitIdentity(OM_uint32 *minor,
     if (GSS_ERROR(major))
         return major;
 
-    ctx->state = EAP_STATE_AUTHENTICATE;
+    ctx->state = GSSEAP_STATE_AUTHENTICATE;
 
+    *minor = 0;
     return GSS_S_CONTINUE_NEEDED;
 }
 
@@ -402,6 +443,8 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
     struct wpabuf *resp = NULL;
     int initialContextToken;
 
+    *minor = 0;
+
     initialContextToken = (inputToken == GSS_C_NO_BUFFER ||
                            inputToken->length == 0);
 
@@ -420,6 +463,7 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
                                                  &eapConfig);
         if (ctx->initiatorCtx.eap == NULL) {
             major = GSS_S_FAILURE;
+            *minor = GSSEAP_PEER_SM_INIT_FAILURE;
             goto cleanup;
         }
 
@@ -439,20 +483,22 @@ eapGssSmInitAuthenticate(OM_uint32 *minor,
 
         resp = eap_get_eapRespData(ctx->initiatorCtx.eap);
     } else if (ctx->flags & CTX_FLAG_EAP_SUCCESS) {
-        major = initReady(minor, ctx);
+        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;
+        ctx->state = GSSEAP_STATE_EXTENSIONS_REQ;
     } 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:
@@ -479,27 +525,6 @@ cleanup:
 }
 
 static OM_uint32
-initGssChannelBindings(OM_uint32 *minor,
-                       gss_ctx_id_t ctx,
-                       gss_channel_bindings_t chanBindings,
-                       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,
@@ -511,23 +536,17 @@ eapGssSmInitExtensionsReq(OM_uint32 *minor,
                           gss_buffer_t inputToken,
                           gss_buffer_t outputToken)
 {
-    OM_uint32 major, tmpMinor;
-    gss_buffer_desc cbToken = GSS_C_EMPTY_BUFFER;
+    OM_uint32 major;
 
-    major = initGssChannelBindings(minor, ctx, chanBindings, &cbToken);
+    major = gssEapMakeExtensions(minor, cred, ctx, chanBindings, outputToken);
     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;
-    }
+    assert(outputToken->value != NULL);
 
-    gss_release_buffer(&tmpMinor, &cbToken);
+    ctx->state = GSSEAP_STATE_EXTENSIONS_RESP;
 
+    *minor = 0;
     return GSS_S_CONTINUE_NEEDED;
 }
 
@@ -543,16 +562,15 @@ eapGssSmInitExtensionsResp(OM_uint32 *minor,
                            gss_buffer_t inputToken,
                            gss_buffer_t outputToken)
 {
-#ifdef GSSEAP_ENABLE_REAUTH
     OM_uint32 major;
 
-    major = gssEapStoreReauthCreds(minor, ctx, cred, inputToken);
+    major = gssEapVerifyExtensions(minor, cred, ctx, chanBindings, inputToken);
     if (GSS_ERROR(major))
         return major;
-#endif
 
-    ctx->state = EAP_STATE_ESTABLISHED;
+    ctx->state = GSSEAP_STATE_ESTABLISHED;
 
+    *minor = 0;
     return GSS_S_COMPLETE;
 }
 
@@ -569,10 +587,43 @@ eapGssSmInitEstablished(OM_uint32 *minor,
                         gss_buffer_t outputToken)
 {
     /* Called with already established context */
-    *minor = EINVAL;
+    *minor = GSSEAP_CONTEXT_ESTABLISHED;
     return GSS_S_BAD_STATUS;
 }
 
+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;
+    }
+
+    return major;
+}
+
 static struct gss_eap_initiator_sm {
     enum gss_eap_token_type inputTokenType;
     enum gss_eap_token_type outputTokenType;
@@ -587,13 +638,14 @@ static struct gss_eap_initiator_sm {
                               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         },
+    { 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         },
+    { TOK_TYPE_CONTEXT_ERR, TOK_TYPE_NONE,          eapGssSmInitError               },
 #ifdef GSSEAP_ENABLE_REAUTH
-    { TOK_TYPE_GSS_REAUTH, TOK_TYPE_GSS_REAUTH, eapGssSmInitGssReauth           },
+    { TOK_TYPE_GSS_REAUTH,  TOK_TYPE_GSS_REAUTH,    eapGssSmInitGssReauth           },
 #endif
 };
 
@@ -619,18 +671,16 @@ gss_init_sec_context(OM_uint32 *minor,
     gss_buffer_desc innerInputToken;
     gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
     enum gss_eap_token_type tokType;
+    int initialContextToken = 0;
 
     *minor = 0;
 
     output_token->length = 0;
     output_token->value = NULL;
 
-    if (cred != GSS_C_NO_CREDENTIAL && !(cred->flags & CRED_FLAG_INITIATE)) {
-        return GSS_S_NO_CRED;
-    }
-
     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;
         }
 
@@ -640,26 +690,56 @@ gss_init_sec_context(OM_uint32 *minor,
 
         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;
     }
 
     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,
+                                      &ctx->defaultCred,
+                                      NULL,
+                                      NULL);
+            if (GSS_ERROR(major))
+                goto cleanup;
+        }
+
+        cred = ctx->defaultCred;
+    }
+
+    GSSEAP_MUTEX_LOCK(&cred->mutex);
+
+#ifdef GSSEAP_ENABLE_REAUTH
+    if (initialContextToken && gssEapCanReauthP(cred, target_name, time_req))
+        ctx->state = GSSEAP_STATE_KRB_REAUTH;
+#endif
+
+    if ((cred->flags & CRED_FLAG_INITIATE) == 0) {
+        major = GSS_S_NO_CRED;
+        *minor = GSSEAP_CRED_USAGE_MISMATCH;
+        goto cleanup;
+    }
+
     sm = &eapGssInitiatorSm[ctx->state];
 
-    if (input_token != GSS_C_NO_BUFFER) {
+    if (input_token != GSS_C_NO_BUFFER && input_token->length != 0) {
         major = gssEapVerifyToken(minor, ctx, input_token,
                                   &tokType, &innerInputToken);
         if (GSS_ERROR(major))
             goto cleanup;
 
-        if (tokType != sm->inputTokenType) {
+        if (tokType == TOK_TYPE_CONTEXT_ERR) {
+            ctx->state = GSSEAP_STATE_ERROR;
+        } else if (tokType != sm->inputTokenType) {
             major = GSS_S_DEFECTIVE_TOKEN;
+            *minor = GSSEAP_WRONG_TOK_ID;
             goto cleanup;
         }
     } else {
@@ -706,9 +786,11 @@ gss_init_sec_context(OM_uint32 *minor,
     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))
@@ -720,14 +802,6 @@ cleanup:
 }
 
 #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,
@@ -747,7 +821,7 @@ eapGssSmInitGssReauth(OM_uint32 *minor,
 
     assert(cred != GSS_C_NO_CREDENTIAL);
 
-    ctx->flags |= CTX_FLAG_KRB_REAUTH_GSS;
+    ctx->flags |= CTX_FLAG_KRB_REAUTH;
 
     if (inputToken->length == 0) {
         major = initBegin(minor, cred, ctx, target, mech,
@@ -783,7 +857,7 @@ eapGssSmInitGssReauth(OM_uint32 *minor,
         major = gssEapReauthComplete(minor, ctx, cred, actualMech, timeRec);
         if (GSS_ERROR(major))
             goto cleanup;
-        ctx->state = EAP_STATE_ESTABLISHED;
+        ctx->state = GSSEAP_STATE_ESTABLISHED;
     }
 
 cleanup:
@@ -792,5 +866,3 @@ cleanup:
     return major;
 }
 #endif /* GSSEAP_ENABLE_REAUTH */
-
-