lib: Use asn1_set_error()
[obnox/samba/samba-obnox.git] / source3 / libsmb / clispnego.c
index 92543736ff258b767ee766c6a258965c055d8426..61ccdae03ef93ccaaf2a551633cddd6830349780 100644 (file)
@@ -4,10 +4,11 @@
    Copyright (C) Andrew Tridgell 2001
    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2002
    Copyright (C) Luke Howard     2003
-   
+   Copyright (C) Jeremy Allison 2010
+
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
    
    This program is distributed in the hope that it will be useful,
    GNU General Public License for more details.
    
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "includes.h"
+#include "../libcli/auth/spnego.h"
+#include "smb_krb5.h"
+#include "../lib/util/asn1.h"
 
 /*
-  generate a negTokenInit packet given a GUID, a list of supported
-  OIDs (the mechanisms) and a principal name string 
+  generate a negTokenInit packet given a list of supported
+  OIDs (the mechanisms) a blob, and a principal name string
 */
-DATA_BLOB spnego_gen_negTokenInit(uint8 guid[16], 
-                                 const char *OIDs[], 
+
+DATA_BLOB spnego_gen_negTokenInit(TALLOC_CTX *ctx,
+                                 const char *OIDs[],
+                                 DATA_BLOB *psecblob,
                                  const char *principal)
 {
        int i;
-       ASN1_DATA data;
-       DATA_BLOB ret;
+       ASN1_DATA *data;
+       DATA_BLOB ret = data_blob_null;
 
-       memset(&data, 0, sizeof(data));
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return data_blob_null;
+       }
 
-       asn1_write(&data, guid, 16);
-       asn1_push_tag(&data,ASN1_APPLICATION(0));
-       asn1_write_OID(&data,OID_SPNEGO);
-       asn1_push_tag(&data,ASN1_CONTEXT(0));
-       asn1_push_tag(&data,ASN1_SEQUENCE(0));
+       if (!asn1_push_tag(data,ASN1_APPLICATION(0))) goto err;
+       if (!asn1_write_OID(data,OID_SPNEGO)) goto err;
+       if (!asn1_push_tag(data,ASN1_CONTEXT(0))) goto err;
+       if (!asn1_push_tag(data,ASN1_SEQUENCE(0))) goto err;
 
-       asn1_push_tag(&data,ASN1_CONTEXT(0));
-       asn1_push_tag(&data,ASN1_SEQUENCE(0));
+       if (!asn1_push_tag(data,ASN1_CONTEXT(0))) goto err;
+       if (!asn1_push_tag(data,ASN1_SEQUENCE(0))) goto err;
        for (i=0; OIDs[i]; i++) {
-               asn1_write_OID(&data,OIDs[i]);
+               if (!asn1_write_OID(data,OIDs[i])) goto err;
        }
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       asn1_push_tag(&data, ASN1_CONTEXT(3));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_write_GeneralString(&data,principal);
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       asn1_pop_tag(&data);
-
-       if (data.has_error) {
-               DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs));
-               asn1_free(&data);
+       if (!asn1_pop_tag(data)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
+
+       if (psecblob && psecblob->length && psecblob->data) {
+               if (!asn1_push_tag(data, ASN1_CONTEXT(2))) goto err;
+               if (!asn1_write_OctetString(data,psecblob->data,
+                       psecblob->length)) goto err;
+               if (!asn1_pop_tag(data)) goto err;
        }
 
-       ret = data_blob(data.data, data.length);
-       asn1_free(&data);
-
-       return ret;
-}
-
-/*
-  Generate a negTokenInit as used by the client side ... It has a mechType
-  (OID), and a mechToken (a security blob) ... 
-
-  Really, we need to break out the NTLMSSP stuff as well, because it could be
-  raw in the packets!
-*/
-DATA_BLOB gen_negTokenInit(const char *OID, DATA_BLOB blob)
-{
-       ASN1_DATA data;
-       DATA_BLOB ret;
-
-       memset(&data, 0, sizeof(data));
-
-       asn1_push_tag(&data, ASN1_APPLICATION(0));
-       asn1_write_OID(&data,OID_SPNEGO);
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
+       if (principal) {
+               if (!asn1_push_tag(data, ASN1_CONTEXT(3))) goto err;
+               if (!asn1_push_tag(data, ASN1_SEQUENCE(0))) goto err;
+               if (!asn1_push_tag(data, ASN1_CONTEXT(0))) goto err;
+               if (!asn1_write_GeneralString(data,principal)) goto err;
+               if (!asn1_pop_tag(data)) goto err;
+               if (!asn1_pop_tag(data)) goto err;
+               if (!asn1_pop_tag(data)) goto err;
+       }
 
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
-       asn1_write_OID(&data, OID);
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
+       if (!asn1_pop_tag(data)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
 
-       asn1_push_tag(&data, ASN1_CONTEXT(2));
-       asn1_write_OctetString(&data,blob.data,blob.length);
-       asn1_pop_tag(&data);
+       if (!asn1_pop_tag(data)) goto err;
 
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
+       ret = data_blob_talloc(ctx, data->data, data->length);
 
-       asn1_pop_tag(&data);
+  err:
 
-       if (data.has_error) {
-               DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs));
-               asn1_free(&data);
+       if (asn1_has_error(data)) {
+               DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data->ofs));
        }
 
-       ret = data_blob(data.data, data.length);
-       asn1_free(&data);
+       asn1_free(data);
 
        return ret;
 }
@@ -123,270 +96,262 @@ DATA_BLOB gen_negTokenInit(const char *OID, DATA_BLOB blob)
   parse a negTokenInit packet giving a GUID, a list of supported
   OIDs (the mechanisms) and a principal name string 
 */
-BOOL spnego_parse_negTokenInit(DATA_BLOB blob,
-                              char *OIDs[ASN1_MAX_OIDS], 
-                              char **principal)
+bool spnego_parse_negTokenInit(TALLOC_CTX *ctx,
+                              DATA_BLOB blob,
+                              char *OIDs[ASN1_MAX_OIDS],
+                              char **principal,
+                              DATA_BLOB *secblob)
 {
        int i;
-       BOOL ret;
-       ASN1_DATA data;
-
-       asn1_load(&data, blob);
-
-       asn1_start_tag(&data,ASN1_APPLICATION(0));
-       asn1_check_OID(&data,OID_SPNEGO);
-       asn1_start_tag(&data,ASN1_CONTEXT(0));
-       asn1_start_tag(&data,ASN1_SEQUENCE(0));
-
-       asn1_start_tag(&data,ASN1_CONTEXT(0));
-       asn1_start_tag(&data,ASN1_SEQUENCE(0));
-       for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS; i++) {
-               char *oid = NULL;
-               asn1_read_OID(&data,&oid);
-               OIDs[i] = oid;
+       bool ret = false;
+       ASN1_DATA *data;
+
+       for (i = 0; i < ASN1_MAX_OIDS; i++) {
+               OIDs[i] = NULL;
        }
-       OIDs[i] = NULL;
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
 
-       asn1_start_tag(&data, ASN1_CONTEXT(3));
-       asn1_start_tag(&data, ASN1_SEQUENCE(0));
-       asn1_start_tag(&data, ASN1_CONTEXT(0));
-       asn1_read_GeneralString(&data,principal);
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
+       if (principal) {
+               *principal = NULL;
+       }
+       if (secblob) {
+               *secblob = data_blob_null;
+       }
 
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return false;
+       }
 
-       asn1_end_tag(&data);
+       if (!asn1_load(data, blob)) goto err;
 
-       ret = !data.has_error;
-       asn1_free(&data);
-       return ret;
-}
+       if (!asn1_start_tag(data,ASN1_APPLICATION(0))) goto err;
 
+       if (!asn1_check_OID(data,OID_SPNEGO)) goto err;
 
-/*
-  generate a negTokenTarg packet given a list of OIDs and a security blob
-*/
-DATA_BLOB gen_negTokenTarg(const char *OIDs[], DATA_BLOB blob)
-{
-       int i;
-       ASN1_DATA data;
-       DATA_BLOB ret;
+       /* negTokenInit  [0]  NegTokenInit */
+       if (!asn1_start_tag(data,ASN1_CONTEXT(0))) goto err;
+       if (!asn1_start_tag(data,ASN1_SEQUENCE(0))) goto err;
 
-       memset(&data, 0, sizeof(data));
+       /* mechTypes [0] MechTypeList  OPTIONAL */
 
-       asn1_push_tag(&data, ASN1_APPLICATION(0));
-       asn1_write_OID(&data,OID_SPNEGO);
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
+       /* Not really optional, we depend on this to decide
+        * what mechanisms we have to work with. */
 
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
-       for (i=0; OIDs[i]; i++) {
-               asn1_write_OID(&data,OIDs[i]);
+       if (!asn1_start_tag(data,ASN1_CONTEXT(0))) goto err;
+       if (!asn1_start_tag(data,ASN1_SEQUENCE(0))) goto err;
+       for (i=0; asn1_tag_remaining(data) > 0 && i < ASN1_MAX_OIDS-1; i++) {
+               if (!asn1_read_OID(data,ctx, &OIDs[i])) {
+                       goto err;
+               }
+               if (asn1_has_error(data)) {
+                       goto err;
+               }
        }
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       asn1_push_tag(&data, ASN1_CONTEXT(2));
-       asn1_write_OctetString(&data,blob.data,blob.length);
-       asn1_pop_tag(&data);
-
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       asn1_pop_tag(&data);
-
-       if (data.has_error) {
-               DEBUG(1,("Failed to build negTokenTarg at offset %d\n", (int)data.ofs));
-               asn1_free(&data);
+       OIDs[i] = NULL;
+       if (!asn1_end_tag(data)) goto err;
+       if (!asn1_end_tag(data)) goto err;
+
+       /*
+         Win7 + Live Sign-in Assistant attaches a mechToken
+         ASN1_CONTEXT(2) to the negTokenInit packet
+         which breaks our negotiation if we just assume
+         the next tag is ASN1_CONTEXT(3).
+       */
+
+       if (asn1_peek_tag(data, ASN1_CONTEXT(1))) {
+               uint8_t flags;
+
+               /* reqFlags [1] ContextFlags  OPTIONAL */
+               if (!asn1_start_tag(data, ASN1_CONTEXT(1))) goto err;
+               if (!asn1_start_tag(data, ASN1_BIT_STRING)) goto err;
+               while (asn1_tag_remaining(data) > 0) {
+                       if (!asn1_read_uint8(data, &flags)) goto err;
+               }
+               if (!asn1_end_tag(data)) goto err;
+               if (!asn1_end_tag(data)) goto err;
        }
 
-       ret = data_blob(data.data, data.length);
-       asn1_free(&data);
-
-       return ret;
-}
-
+       if (asn1_peek_tag(data, ASN1_CONTEXT(2))) {
+               DATA_BLOB sblob = data_blob_null;
+               /* mechToken [2] OCTET STRING  OPTIONAL */
+               if (!asn1_start_tag(data, ASN1_CONTEXT(2))) goto err;
+               if (!asn1_read_OctetString(data, ctx, &sblob)) goto err;
+               if (!asn1_end_tag(data)) {
+                       data_blob_free(&sblob);
+                       goto err;
+               }
+               if (secblob) {
+                       *secblob = sblob;
+               } else {
+                       data_blob_free(&sblob);
+               }
+       }
 
-/*
-  parse a negTokenTarg packet giving a list of OIDs and a security blob
-*/
-BOOL parse_negTokenTarg(DATA_BLOB blob, char *OIDs[ASN1_MAX_OIDS], DATA_BLOB *secblob)
-{
-       int i;
-       ASN1_DATA data;
-
-       asn1_load(&data, blob);
-       asn1_start_tag(&data, ASN1_APPLICATION(0));
-       asn1_check_OID(&data,OID_SPNEGO);
-       asn1_start_tag(&data, ASN1_CONTEXT(0));
-       asn1_start_tag(&data, ASN1_SEQUENCE(0));
-
-       asn1_start_tag(&data, ASN1_CONTEXT(0));
-       asn1_start_tag(&data, ASN1_SEQUENCE(0));
-       for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS; i++) {
-               char *oid = NULL;
-               asn1_read_OID(&data,&oid);
-               OIDs[i] = oid;
+       if (asn1_peek_tag(data, ASN1_CONTEXT(3))) {
+               char *princ = NULL;
+               /* mechListMIC [3] OCTET STRING  OPTIONAL */
+               if (!asn1_start_tag(data, ASN1_CONTEXT(3))) goto err;
+               if (!asn1_start_tag(data, ASN1_SEQUENCE(0))) goto err;
+               if (!asn1_start_tag(data, ASN1_CONTEXT(0))) goto err;
+               if (!asn1_read_GeneralString(data, ctx, &princ)) goto err;
+               if (!asn1_end_tag(data)) goto err;
+               if (!asn1_end_tag(data)) goto err;
+               if (!asn1_end_tag(data)) goto err;
+               if (principal) {
+                       *principal = princ;
+               } else {
+                       TALLOC_FREE(princ);
+               }
        }
-       OIDs[i] = NULL;
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
 
-       asn1_start_tag(&data, ASN1_CONTEXT(2));
-       asn1_read_OctetString(&data,secblob);
-       asn1_end_tag(&data);
+       if (!asn1_end_tag(data)) goto err;
+       if (!asn1_end_tag(data)) goto err;
+
+       if (!asn1_end_tag(data)) goto err;
 
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
+       ret = !asn1_has_error(data);
 
-       asn1_end_tag(&data);
+  err:
 
-       if (data.has_error) {
-               DEBUG(1,("Failed to parse negTokenTarg at offset %d\n", (int)data.ofs));
-               asn1_free(&data);
-               return False;
+       if (asn1_has_error(data)) {
+               int j;
+               if (principal) {
+                       TALLOC_FREE(*principal);
+               }
+               if (secblob) {
+                       data_blob_free(secblob);
+               }
+               for(j = 0; j < i && j < ASN1_MAX_OIDS-1; j++) {
+                       TALLOC_FREE(OIDs[j]);
+               }
        }
 
-       asn1_free(&data);
-       return True;
+       asn1_free(data);
+       return ret;
 }
 
 /*
   generate a krb5 GSS-API wrapper packet given a ticket
 */
-DATA_BLOB spnego_gen_krb5_wrap(DATA_BLOB ticket, const uint8 tok_id[2])
+DATA_BLOB spnego_gen_krb5_wrap(TALLOC_CTX *ctx, const DATA_BLOB ticket, const uint8_t tok_id[2])
 {
-       ASN1_DATA data;
-       DATA_BLOB ret;
-
-       memset(&data, 0, sizeof(data));
-
-       asn1_push_tag(&data, ASN1_APPLICATION(0));
-       asn1_write_OID(&data, OID_KERBEROS5);
+       ASN1_DATA *data;
+       DATA_BLOB ret = data_blob_null;
 
-       asn1_write(&data, tok_id, 2);
-       asn1_write(&data, ticket.data, ticket.length);
-       asn1_pop_tag(&data);
-
-       if (data.has_error) {
-               DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data.ofs));
-               asn1_free(&data);
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return data_blob_null;
        }
 
-       ret = data_blob(data.data, data.length);
-       asn1_free(&data);
-
-       return ret;
-}
+       if (!asn1_push_tag(data, ASN1_APPLICATION(0))) goto err;
+       if (!asn1_write_OID(data, OID_KERBEROS5)) goto err;
 
-/*
-  parse a krb5 GSS-API wrapper packet giving a ticket
-*/
-BOOL spnego_parse_krb5_wrap(DATA_BLOB blob, DATA_BLOB *ticket, uint8 tok_id[2])
-{
-       BOOL ret;
-       ASN1_DATA data;
-       int data_remaining;
+       if (!asn1_write(data, tok_id, 2)) goto err;
+       if (!asn1_write(data, ticket.data, ticket.length)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
 
-       asn1_load(&data, blob);
-       asn1_start_tag(&data, ASN1_APPLICATION(0));
-       asn1_check_OID(&data, OID_KERBEROS5);
+       ret = data_blob_talloc(ctx, data->data, data->length);
 
-       data_remaining = asn1_tag_remaining(&data);
+  err:
 
-       if (data_remaining < 3) {
-               data.has_error = True;
-       } else {
-               asn1_read(&data, tok_id, 2);
-               data_remaining -= 2;
-               *ticket = data_blob(NULL, data_remaining);
-               asn1_read(&data, ticket->data, ticket->length);
+       if (asn1_has_error(data)) {
+               DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data->ofs));
        }
 
-       asn1_end_tag(&data);
-
-       ret = !data.has_error;
-
-       asn1_free(&data);
+       asn1_free(data);
 
        return ret;
 }
 
-
 /* 
-   generate a SPNEGO negTokenTarg packet, ready for a EXTENDED_SECURITY
-   kerberos session setup 
+   generate a SPNEGO krb5 negTokenInit packet, ready for a EXTENDED_SECURITY
+   kerberos session setup
 */
-DATA_BLOB spnego_gen_negTokenTarg(const char *principal, int time_offset, DATA_BLOB *session_key_krb5)
+int spnego_gen_krb5_negTokenInit(TALLOC_CTX *ctx,
+                           const char *principal, int time_offset,
+                           DATA_BLOB *targ,
+                           DATA_BLOB *session_key_krb5, uint32_t extra_ap_opts,
+                           const char *ccname, time_t *expire_time)
 {
-       DATA_BLOB tkt, tkt_wrapped, targ;
-       const char *krb_mechs[] = {OID_KERBEROS5_OLD, OID_NTLMSSP, NULL};
+       int retval;
+       DATA_BLOB tkt, tkt_wrapped;
+       const char *krb_mechs[] = {OID_KERBEROS5_OLD, OID_KERBEROS5, OID_NTLMSSP, NULL};
 
        /* get a kerberos ticket for the service and extract the session key */
-       tkt = cli_krb5_get_ticket(principal, time_offset, session_key_krb5);
-
-       if (tkt.data == NULL)
-               return tkt;
+       retval = cli_krb5_get_ticket(ctx, principal, time_offset,
+                                         &tkt, session_key_krb5,
+                                         extra_ap_opts, ccname,
+                                         expire_time, NULL);
+       if (retval) {
+               return retval;
+       }
 
        /* wrap that up in a nice GSS-API wrapping */
-       tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ);
+       tkt_wrapped = spnego_gen_krb5_wrap(ctx, tkt, TOK_ID_KRB_AP_REQ);
 
        /* and wrap that in a shiny SPNEGO wrapper */
-       targ = gen_negTokenTarg(krb_mechs, tkt_wrapped);
+       *targ = spnego_gen_negTokenInit(ctx, krb_mechs, &tkt_wrapped, NULL);
 
        data_blob_free(&tkt_wrapped);
        data_blob_free(&tkt);
 
-       return targ;
+       return retval;
 }
 
 
 /*
   parse a spnego NTLMSSP challenge packet giving two security blobs
 */
-BOOL spnego_parse_challenge(const DATA_BLOB blob,
+bool spnego_parse_challenge(TALLOC_CTX *ctx, const DATA_BLOB blob,
                            DATA_BLOB *chal1, DATA_BLOB *chal2)
 {
-       BOOL ret;
-       ASN1_DATA data;
+       bool ret = false;
+       ASN1_DATA *data;
 
        ZERO_STRUCTP(chal1);
        ZERO_STRUCTP(chal2);
 
-       asn1_load(&data, blob);
-       asn1_start_tag(&data,ASN1_CONTEXT(1));
-       asn1_start_tag(&data,ASN1_SEQUENCE(0));
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return false;
+       }
+
+       if (!asn1_load(data, blob)) goto err;
+       if (!asn1_start_tag(data,ASN1_CONTEXT(1))) goto err;
+       if (!asn1_start_tag(data,ASN1_SEQUENCE(0))) goto err;
 
-       asn1_start_tag(&data,ASN1_CONTEXT(0));
-       asn1_check_enumerated(&data,1);
-       asn1_end_tag(&data);
+       if (!asn1_start_tag(data,ASN1_CONTEXT(0))) goto err;
+       if (!asn1_check_enumerated(data,1)) goto err;
+       if (!asn1_end_tag(data)) goto err;
 
-       asn1_start_tag(&data,ASN1_CONTEXT(1));
-       asn1_check_OID(&data, OID_NTLMSSP);
-       asn1_end_tag(&data);
+       if (!asn1_start_tag(data,ASN1_CONTEXT(1))) goto err;
+       if (!asn1_check_OID(data, OID_NTLMSSP)) goto err;
+       if (!asn1_end_tag(data)) goto err;
 
-       asn1_start_tag(&data,ASN1_CONTEXT(2));
-       asn1_read_OctetString(&data, chal1);
-       asn1_end_tag(&data);
+       if (!asn1_start_tag(data,ASN1_CONTEXT(2))) goto err;
+       if (!asn1_read_OctetString(data, ctx, chal1)) goto err;
+       if (!asn1_end_tag(data)) goto err;
 
        /* the second challenge is optional (XP doesn't send it) */
-       if (asn1_tag_remaining(&data)) {
-               asn1_start_tag(&data,ASN1_CONTEXT(3));
-               asn1_read_OctetString(&data, chal2);
-               asn1_end_tag(&data);
+       if (asn1_tag_remaining(data)) {
+               if (!asn1_start_tag(data,ASN1_CONTEXT(3))) goto err;
+               if (!asn1_read_OctetString(data, ctx, chal2)) goto err;
+               if (!asn1_end_tag(data)) goto err;
        }
 
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
+       if (!asn1_end_tag(data)) goto err;
+       if (!asn1_end_tag(data)) goto err;
 
-       ret = !data.has_error;
-       asn1_free(&data);
+       ret = !asn1_has_error(data);
+
+  err:
+
+       if (asn1_has_error(data)) {
+               data_blob_free(chal1);
+               data_blob_free(chal2);
+       }
+
+       asn1_free(data);
        return ret;
 }
 
@@ -394,24 +359,29 @@ BOOL spnego_parse_challenge(const DATA_BLOB blob,
 /*
  generate a SPNEGO auth packet. This will contain the encrypted passwords
 */
-DATA_BLOB spnego_gen_auth(DATA_BLOB blob)
+DATA_BLOB spnego_gen_auth(TALLOC_CTX *ctx, DATA_BLOB blob)
 {
-       ASN1_DATA data;
-       DATA_BLOB ret;
+       ASN1_DATA *data;
+       DATA_BLOB ret = data_blob_null;
+
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return data_blob_null;
+       }
 
-       memset(&data, 0, sizeof(data));
+       if (!asn1_push_tag(data, ASN1_CONTEXT(1))) goto err;
+       if (!asn1_push_tag(data, ASN1_SEQUENCE(0))) goto err;
+       if (!asn1_push_tag(data, ASN1_CONTEXT(2))) goto err;
+       if (!asn1_write_OctetString(data,blob.data,blob.length)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
+       if (!asn1_pop_tag(data)) goto err;
 
-       asn1_push_tag(&data, ASN1_CONTEXT(1));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
-       asn1_push_tag(&data, ASN1_CONTEXT(2));
-       asn1_write_OctetString(&data,blob.data,blob.length);    
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
+       ret = data_blob_talloc(ctx, data->data, data->length);
 
-       ret = data_blob(data.data, data.length);
+ err:
 
-       asn1_free(&data);
+       asn1_free(data);
 
        return ret;
 }
@@ -419,118 +389,80 @@ DATA_BLOB spnego_gen_auth(DATA_BLOB blob)
 /*
  parse a SPNEGO auth packet. This contains the encrypted passwords
 */
-BOOL spnego_parse_auth(DATA_BLOB blob, DATA_BLOB *auth)
-{
-       ASN1_DATA data;
-
-       asn1_load(&data, blob);
-       asn1_start_tag(&data, ASN1_CONTEXT(1));
-       asn1_start_tag(&data, ASN1_SEQUENCE(0));
-       asn1_start_tag(&data, ASN1_CONTEXT(2));
-       asn1_read_OctetString(&data,auth);
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
-
-       if (data.has_error) {
-               DEBUG(3,("spnego_parse_auth failed at %d\n", (int)data.ofs));
-               asn1_free(&data);
-               return False;
-       }
-
-       asn1_free(&data);
-       return True;
-}
-
-/*
-  generate a minimal SPNEGO response packet.  Doesn't contain much.
-*/
-DATA_BLOB spnego_gen_auth_response(DATA_BLOB *reply, NTSTATUS nt_status,
-                                  const char *mechOID)
+bool spnego_parse_auth_response(TALLOC_CTX *ctx,
+                               DATA_BLOB blob, NTSTATUS nt_status,
+                               const char *mechOID,
+                               DATA_BLOB *auth)
 {
-       ASN1_DATA data;
-       DATA_BLOB ret;
-       uint8 negResult;
+       ASN1_DATA *data;
+       uint8_t negResult;
+       bool ret = false;
 
        if (NT_STATUS_IS_OK(nt_status)) {
-               negResult = SPNEGO_NEG_RESULT_ACCEPT;
+               negResult = SPNEGO_ACCEPT_COMPLETED;
        } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
-               negResult = SPNEGO_NEG_RESULT_INCOMPLETE; 
+               negResult = SPNEGO_ACCEPT_INCOMPLETE;
        } else {
-               negResult = SPNEGO_NEG_RESULT_REJECT; 
+               negResult = SPNEGO_REJECT;
        }
 
-       ZERO_STRUCT(data);
-
-       asn1_push_tag(&data, ASN1_CONTEXT(1));
-       asn1_push_tag(&data, ASN1_SEQUENCE(0));
-       asn1_push_tag(&data, ASN1_CONTEXT(0));
-       asn1_write_enumerated(&data, negResult);
-       asn1_pop_tag(&data);
-
-       if (reply->data != NULL) {
-               asn1_push_tag(&data,ASN1_CONTEXT(1));
-               asn1_write_OID(&data, mechOID);
-               asn1_pop_tag(&data);
-               
-               asn1_push_tag(&data,ASN1_CONTEXT(2));
-               asn1_write_OctetString(&data, reply->data, reply->length);
-               asn1_pop_tag(&data);
+       data = asn1_init(talloc_tos());
+       if (data == NULL) {
+               return false;
        }
 
-       asn1_pop_tag(&data);
-       asn1_pop_tag(&data);
-
-       ret = data_blob(data.data, data.length);
-       asn1_free(&data);
-       return ret;
-}
-
-/*
- parse a SPNEGO NTLMSSP auth packet. This contains the encrypted passwords
-*/
-BOOL spnego_parse_auth_response(DATA_BLOB blob, NTSTATUS nt_status, 
-                               DATA_BLOB *auth)
-{
-       ASN1_DATA data;
-       uint8 negResult;
-
-       if (NT_STATUS_IS_OK(nt_status)) {
-               negResult = SPNEGO_NEG_RESULT_ACCEPT;
-       } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
-               negResult = SPNEGO_NEG_RESULT_INCOMPLETE;
-       } else {
-               negResult = SPNEGO_NEG_RESULT_REJECT;
+       *auth = data_blob_null;
+
+       if (!asn1_load(data, blob)) goto err;
+       if (!asn1_start_tag(data, ASN1_CONTEXT(1))) goto err;
+       if (!asn1_start_tag(data, ASN1_SEQUENCE(0))) goto err;
+       if (!asn1_start_tag(data, ASN1_CONTEXT(0))) goto err;
+       if (!asn1_check_enumerated(data, negResult)) goto err;
+       if (!asn1_end_tag(data)) goto err;
+
+       if (asn1_tag_remaining(data)) {
+               if (!asn1_start_tag(data,ASN1_CONTEXT(1))) goto err;
+               if (!asn1_check_OID(data, mechOID)) goto err;
+               if (!asn1_end_tag(data)) goto err;
+
+               if (asn1_tag_remaining(data)) {
+                       if (!asn1_start_tag(data,ASN1_CONTEXT(2))) goto err;
+                       if (!asn1_read_OctetString(data, ctx, auth)) goto err;
+                       if (!asn1_end_tag(data)) goto err;
+               }
+       } else if (negResult == SPNEGO_ACCEPT_INCOMPLETE) {
+               asn1_set_error(data);
+               goto err;
        }
 
-       asn1_load(&data, blob);
-       asn1_start_tag(&data, ASN1_CONTEXT(1));
-       asn1_start_tag(&data, ASN1_SEQUENCE(0));
-       asn1_start_tag(&data, ASN1_CONTEXT(0));
-       asn1_check_enumerated(&data, negResult);
-       asn1_end_tag(&data);
-
-       if (negResult == SPNEGO_NEG_RESULT_INCOMPLETE) {
-               asn1_start_tag(&data,ASN1_CONTEXT(1));
-               asn1_check_OID(&data, OID_NTLMSSP);
-               asn1_end_tag(&data);
-               
-               asn1_start_tag(&data,ASN1_CONTEXT(2));
-               asn1_read_OctetString(&data, auth);
-               asn1_end_tag(&data);
+       /* Binding against Win2K DC returns a duplicate of the responseToken in
+        * the optional mechListMIC field. This is a bug in Win2K. We ignore
+        * this field if it exists. Win2K8 may return a proper mechListMIC at
+        * which point we need to implement the integrity checking. */
+       if (asn1_tag_remaining(data)) {
+               DATA_BLOB mechList = data_blob_null;
+               if (!asn1_start_tag(data, ASN1_CONTEXT(3))) goto err;
+               if (!asn1_read_OctetString(data, ctx, &mechList)) goto err;
+               data_blob_free(&mechList);
+               if (!asn1_end_tag(data)) goto err;
+               DEBUG(5,("spnego_parse_auth_response received mechListMIC, "
+                   "ignoring.\n"));
        }
 
-       asn1_end_tag(&data);
-       asn1_end_tag(&data);
+       if (!asn1_end_tag(data)) goto err;
+       if (!asn1_end_tag(data)) goto err;
+
+       ret = !asn1_has_error(data);
 
-       if (data.has_error) {
-               DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data.ofs));
-               asn1_free(&data);
+  err:
+
+       if (asn1_has_error(data)) {
+               DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data->ofs));
+               asn1_free(data);
                data_blob_free(auth);
-               return False;
+               return false;
        }
 
-       asn1_free(&data);
-       return True;
+       asn1_free(data);
+       return ret;
 }
-