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wireshark/epan/dissectors/packet-spnego.c
Guy Harris 8ed7a73e22 Fix a bunch of warnings. 
Cast away some implicit 64-bit-to-32-bit conversion errors due to use of
sizeof.

Cast away some implicit 64-bit-to-32-bit conversion errors due to use of
strtol() and strtoul().

Change some data types to avoid those implicit conversion warnings.

When assigning a constant to a float, make sure the constant isn't a
double, by appending "f" to the constant.

Constify a bunch of variables, parameters, and return values to
eliminate warnings due to strings being given const qualifiers.  Cast
away those warnings in some cases where an API we don't control forces
us to do so.

Enable a bunch of additional warnings by default.  Note why at least
some of the other warnings aren't enabled.

randpkt.c and text2pcap.c are used to build programs, so they don't need
to be in EXTRA_DIST.

If the user specifies --enable-warnings-as-errors, add -Werror *even if
the user specified --enable-extra-gcc-flags; assume they know what
they're doing and are willing to have the compile fail due to the extra
GCC warnings being treated as errors.

svn path=/trunk/; revision=46748
2012-12-26 05:57:06 +00:00

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/* Do not modify this file. */
/* It is created automatically by the ASN.1 to Wireshark dissector compiler */
/* packet-spnego.c */
/* ../../tools/asn2wrs.py -b -p spnego -c ./spnego.cnf -s ./packet-spnego-template -D . -O ../../epan/dissectors spnego.asn */
/* Input file: packet-spnego-template.c */
#line 1 "../../asn1/spnego/packet-spnego-template.c"
/* packet-spnego.c
* Routines for the simple and protected GSS-API negotiation mechanism
* as described in RFC 2478.
* Copyright 2002, Tim Potter <tpot@samba.org>
* Copyright 2002, Richard Sharpe <rsharpe@ns.aus.com>
* Copyright 2003, Richard Sharpe <rsharpe@richardsharpe.com>
* Copyright 2005, Ronnie Sahlberg (krb decryption)
* Copyright 2005, Anders Broman (converted to asn2wrs generated dissector)
*
* $Id$
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* 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 (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/* The heimdal code for decryption of GSSAPI wrappers using heimdal comes from
Heimdal 1.6 and has been modified for wireshark's requirements.
*/
#include "config.h"
#include <glib.h>
#include <epan/packet.h>
#include <epan/asn1.h>
#include "packet-dcerpc.h"
#include "packet-gssapi.h"
#include "packet-kerberos.h"
#include <epan/crypt/rc4.h>
#include <epan/conversation.h>
#include <epan/emem.h>
#include <epan/asn1.h>
#include <string.h>
#include "packet-ber.h"
#define PNAME "Simple Protected Negotiation"
#define PSNAME "SPNEGO"
#define PFNAME "spnego"
/* Initialize the protocol and registered fields */
static int proto_spnego = -1;
static int proto_spnego_krb5 = -1;
static int hf_spnego_wraptoken = -1;
static int hf_spnego_krb5_oid;
static int hf_spnego_krb5 = -1;
static int hf_spnego_krb5_tok_id = -1;
static int hf_spnego_krb5_sgn_alg = -1;
static int hf_spnego_krb5_seal_alg = -1;
static int hf_spnego_krb5_snd_seq = -1;
static int hf_spnego_krb5_sgn_cksum = -1;
static int hf_spnego_krb5_confounder = -1;
static int hf_spnego_krb5_filler = -1;
static int hf_spnego_krb5_cfx_flags = -1;
static int hf_spnego_krb5_cfx_flags_01 = -1;
static int hf_spnego_krb5_cfx_flags_02 = -1;
static int hf_spnego_krb5_cfx_flags_04 = -1;
static int hf_spnego_krb5_cfx_ec = -1;
static int hf_spnego_krb5_cfx_rrc = -1;
static int hf_spnego_krb5_cfx_seq = -1;
/*--- Included file: packet-spnego-hf.c ---*/
#line 1 "../../asn1/spnego/packet-spnego-hf.c"
static int hf_spnego_negTokenInit = -1; /* NegTokenInit */
static int hf_spnego_negTokenTarg = -1; /* NegTokenTarg */
static int hf_spnego_MechTypeList_item = -1; /* MechType */
static int hf_spnego_principal = -1; /* GeneralString */
static int hf_spnego_mechTypes = -1; /* MechTypeList */
static int hf_spnego_reqFlags = -1; /* ContextFlags */
static int hf_spnego_mechToken = -1; /* T_mechToken */
static int hf_spnego_negTokenInit_mechListMIC = -1; /* T_NegTokenInit_mechListMIC */
static int hf_spnego_negResult = -1; /* T_negResult */
static int hf_spnego_supportedMech = -1; /* T_supportedMech */
static int hf_spnego_responseToken = -1; /* T_responseToken */
static int hf_spnego_mechListMIC = -1; /* T_mechListMIC */
static int hf_spnego_thisMech = -1; /* MechType */
static int hf_spnego_innerContextToken = -1; /* InnerContextToken */
/* named bits */
static int hf_spnego_ContextFlags_delegFlag = -1;
static int hf_spnego_ContextFlags_mutualFlag = -1;
static int hf_spnego_ContextFlags_replayFlag = -1;
static int hf_spnego_ContextFlags_sequenceFlag = -1;
static int hf_spnego_ContextFlags_anonFlag = -1;
static int hf_spnego_ContextFlags_confFlag = -1;
static int hf_spnego_ContextFlags_integFlag = -1;
/*--- End of included file: packet-spnego-hf.c ---*/
#line 80 "../../asn1/spnego/packet-spnego-template.c"
/* Global variables */
static const char *MechType_oid;
gssapi_oid_value *next_level_value;
gboolean saw_mechanism = FALSE;
/* Initialize the subtree pointers */
static gint ett_spnego = -1;
static gint ett_spnego_wraptoken = -1;
static gint ett_spnego_krb5 = -1;
static gint ett_spnego_krb5_cfx_flags = -1;
/*--- Included file: packet-spnego-ett.c ---*/
#line 1 "../../asn1/spnego/packet-spnego-ett.c"
static gint ett_spnego_NegotiationToken = -1;
static gint ett_spnego_MechTypeList = -1;
static gint ett_spnego_PrincipalSeq = -1;
static gint ett_spnego_NegTokenInit = -1;
static gint ett_spnego_ContextFlags = -1;
static gint ett_spnego_NegTokenTarg = -1;
static gint ett_spnego_InitialContextToken_U = -1;
/*--- End of included file: packet-spnego-ett.c ---*/
#line 94 "../../asn1/spnego/packet-spnego-template.c"
/*
* Unfortunately, we have to have a forward declaration of this,
* as the code generated by asn2wrs includes a call before the
* definition.
*/
static int dissect_spnego_PrincipalSeq(gboolean implicit_tag, tvbuff_t *tvb,
int offset, asn1_ctx_t *actx _U_,
proto_tree *tree, int hf_index);
/*--- Included file: packet-spnego-fn.c ---*/
#line 1 "../../asn1/spnego/packet-spnego-fn.c"
static int
dissect_spnego_MechType(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 23 "../../asn1/spnego/spnego.cnf"
gssapi_oid_value *value;
offset = dissect_ber_object_identifier_str(implicit_tag, actx, tree, tvb, offset, hf_index, &MechType_oid);
value = gssapi_lookup_oid_str(MechType_oid);
/*
* Tell our caller the first mechanism we see, so that if
* this is a negTokenInit with a mechToken, it can interpret
* the mechToken according to the first mechType. (There
* might not have been any indication of the mechType
* in prior frames, so we can't necessarily use the
* mechanism from the conversation; i.e., a negTokenInit
* can contain the initial security token for the desired
* mechanism of the initiator - that's the first mechanism
* in the list.)
*/
if (!saw_mechanism) {
if (value)
next_level_value = value;
saw_mechanism = TRUE;
}
return offset;
}
static const ber_sequence_t MechTypeList_sequence_of[1] = {
{ &hf_spnego_MechTypeList_item, BER_CLASS_UNI, BER_UNI_TAG_OID, BER_FLAGS_NOOWNTAG, dissect_spnego_MechType },
};
static int
dissect_spnego_MechTypeList(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 91 "../../asn1/spnego/spnego.cnf"
conversation_t *conversation;
saw_mechanism = FALSE;
offset = dissect_ber_sequence_of(implicit_tag, actx, tree, tvb, offset,
MechTypeList_sequence_of, hf_index, ett_spnego_MechTypeList);
/*
* If we saw a mechType we need to store it in case the negTokenTarg
* does not provide a supportedMech.
*/
if(saw_mechanism){
conversation = find_or_create_conversation(actx->pinfo);
conversation_add_proto_data(conversation, proto_spnego, next_level_value);
}
return offset;
}
static const asn_namedbit ContextFlags_bits[] = {
{ 0, &hf_spnego_ContextFlags_delegFlag, -1, -1, "delegFlag", NULL },
{ 1, &hf_spnego_ContextFlags_mutualFlag, -1, -1, "mutualFlag", NULL },
{ 2, &hf_spnego_ContextFlags_replayFlag, -1, -1, "replayFlag", NULL },
{ 3, &hf_spnego_ContextFlags_sequenceFlag, -1, -1, "sequenceFlag", NULL },
{ 4, &hf_spnego_ContextFlags_anonFlag, -1, -1, "anonFlag", NULL },
{ 5, &hf_spnego_ContextFlags_confFlag, -1, -1, "confFlag", NULL },
{ 6, &hf_spnego_ContextFlags_integFlag, -1, -1, "integFlag", NULL },
{ 0, NULL, 0, 0, NULL, NULL }
};
static int
dissect_spnego_ContextFlags(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_bitstring(implicit_tag, actx, tree, tvb, offset,
ContextFlags_bits, hf_index, ett_spnego_ContextFlags,
NULL);
return offset;
}
static int
dissect_spnego_T_mechToken(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 112 "../../asn1/spnego/spnego.cnf"
tvbuff_t *mechToken_tvb = NULL;
offset = dissect_ber_octet_string(implicit_tag, actx, tree, tvb, offset, hf_index,
&mechToken_tvb);
/*
* Now, we should be able to dispatch, if we've gotten a tvbuff for
* the token and we have information on how to dissect its contents.
*/
if (mechToken_tvb && next_level_value)
call_dissector(next_level_value->handle, mechToken_tvb, actx->pinfo, tree);
return offset;
}
static int
dissect_spnego_T_NegTokenInit_mechListMIC(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 126 "../../asn1/spnego/spnego.cnf"
gint8 class;
gboolean pc;
gint32 tag;
tvbuff_t *mechListMIC_tvb;
/*
* There seems to be two different forms this can take,
* one as an octet string, and one as a general string in a
* sequence.
*
* Peek at the header, and then decide which it is we're seeing.
*/
get_ber_identifier(tvb, offset, &class, &pc, &tag);
if (class == BER_CLASS_UNI && pc && tag == BER_UNI_TAG_SEQUENCE) {
/*
* It's a sequence.
*/
return dissect_spnego_PrincipalSeq(FALSE, tvb, offset, actx, tree,
hf_spnego_mechListMIC);
} else {
/*
* It's not a sequence, so dissect it as an octet string,
* which is what it's supposed to be; that'll cause the
* right error report if it's not an octet string, either.
*/
offset = dissect_ber_octet_string(FALSE, actx, tree, tvb, offset,
hf_spnego_mechListMIC, &mechListMIC_tvb);
/*
* Now, we should be able to dispatch with that tvbuff.
*/
if (mechListMIC_tvb && next_level_value)
call_dissector(next_level_value->handle, mechListMIC_tvb, actx->pinfo, tree);
return offset;
}
return offset;
}
static const ber_sequence_t NegTokenInit_sequence[] = {
{ &hf_spnego_mechTypes , BER_CLASS_CON, 0, BER_FLAGS_OPTIONAL, dissect_spnego_MechTypeList },
{ &hf_spnego_reqFlags , BER_CLASS_CON, 1, BER_FLAGS_OPTIONAL, dissect_spnego_ContextFlags },
{ &hf_spnego_mechToken , BER_CLASS_CON, 2, BER_FLAGS_OPTIONAL, dissect_spnego_T_mechToken },
{ &hf_spnego_negTokenInit_mechListMIC, BER_CLASS_CON, 3, BER_FLAGS_OPTIONAL, dissect_spnego_T_NegTokenInit_mechListMIC },
{ NULL, 0, 0, 0, NULL }
};
static int
dissect_spnego_NegTokenInit(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_sequence(implicit_tag, actx, tree, tvb, offset,
NegTokenInit_sequence, hf_index, ett_spnego_NegTokenInit);
return offset;
}
static const value_string spnego_T_negResult_vals[] = {
{ 0, "accept-completed" },
{ 1, "accept-incomplete" },
{ 2, "reject" },
{ 0, NULL }
};
static int
dissect_spnego_T_negResult(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_integer(implicit_tag, actx, tree, tvb, offset, hf_index,
NULL);
return offset;
}
static int
dissect_spnego_T_supportedMech(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 164 "../../asn1/spnego/spnego.cnf"
conversation_t *conversation;
saw_mechanism = FALSE;
offset = dissect_spnego_MechType(implicit_tag, tvb, offset, actx, tree, hf_index);
/*
* If we saw an explicit mechType we store this in the conversation so that
* it will override any mechType we might have picked up from the
* negTokenInit.
*/
if(saw_mechanism){
conversation = find_or_create_conversation(actx->pinfo);
conversation_add_proto_data(conversation, proto_spnego, next_level_value);
}
return offset;
}
static int
dissect_spnego_T_responseToken(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 187 "../../asn1/spnego/spnego.cnf"
tvbuff_t *responseToken_tvb;
offset = dissect_ber_octet_string(implicit_tag, actx, tree, tvb, offset, hf_index,
&responseToken_tvb);
/*
* Now, we should be able to dispatch, if we've gotten a tvbuff for
* the token and we have information on how to dissect its contents.
* However, we should make sure that there is something in the
* response token ...
*/
if (responseToken_tvb && (tvb_reported_length(responseToken_tvb) > 0) ){
gssapi_oid_value *value=next_level_value;
if(value){
call_dissector(value->handle, responseToken_tvb, actx->pinfo, tree);
}
}
return offset;
}
static int
dissect_spnego_T_mechListMIC(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 214 "../../asn1/spnego/spnego.cnf"
tvbuff_t *mechListMIC_tvb;
offset = dissect_ber_octet_string(implicit_tag, actx, tree, tvb, offset, hf_index,
&mechListMIC_tvb);
/*
* Now, we should be able to dispatch, if we've gotten a tvbuff for
* the MIC and we have information on how to dissect its contents.
*/
if (mechListMIC_tvb && (tvb_reported_length(mechListMIC_tvb) > 0) ){
gssapi_oid_value *value=next_level_value;
if(value){
call_dissector(value->handle, mechListMIC_tvb, actx->pinfo, tree);
}
}
return offset;
}
static const ber_sequence_t NegTokenTarg_sequence[] = {
{ &hf_spnego_negResult , BER_CLASS_CON, 0, BER_FLAGS_OPTIONAL, dissect_spnego_T_negResult },
{ &hf_spnego_supportedMech, BER_CLASS_CON, 1, BER_FLAGS_OPTIONAL, dissect_spnego_T_supportedMech },
{ &hf_spnego_responseToken, BER_CLASS_CON, 2, BER_FLAGS_OPTIONAL, dissect_spnego_T_responseToken },
{ &hf_spnego_mechListMIC , BER_CLASS_CON, 3, BER_FLAGS_OPTIONAL, dissect_spnego_T_mechListMIC },
{ NULL, 0, 0, 0, NULL }
};
static int
dissect_spnego_NegTokenTarg(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_sequence(implicit_tag, actx, tree, tvb, offset,
NegTokenTarg_sequence, hf_index, ett_spnego_NegTokenTarg);
return offset;
}
static const value_string spnego_NegotiationToken_vals[] = {
{ 0, "negTokenInit" },
{ 1, "negTokenTarg" },
{ 0, NULL }
};
static const ber_choice_t NegotiationToken_choice[] = {
{ 0, &hf_spnego_negTokenInit , BER_CLASS_CON, 0, 0, dissect_spnego_NegTokenInit },
{ 1, &hf_spnego_negTokenTarg , BER_CLASS_CON, 1, 0, dissect_spnego_NegTokenTarg },
{ 0, NULL, 0, 0, 0, NULL }
};
static int
dissect_spnego_NegotiationToken(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_choice(actx, tree, tvb, offset,
NegotiationToken_choice, hf_index, ett_spnego_NegotiationToken,
NULL);
return offset;
}
static int
dissect_spnego_GeneralString(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_restricted_string(implicit_tag, BER_UNI_TAG_GeneralString,
actx, tree, tvb, offset, hf_index,
NULL);
return offset;
}
static const ber_sequence_t PrincipalSeq_sequence[] = {
{ &hf_spnego_principal , BER_CLASS_CON, 0, 0, dissect_spnego_GeneralString },
{ NULL, 0, 0, 0, NULL }
};
static int
dissect_spnego_PrincipalSeq(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_sequence(implicit_tag, actx, tree, tvb, offset,
PrincipalSeq_sequence, hf_index, ett_spnego_PrincipalSeq);
return offset;
}
static int
dissect_spnego_InnerContextToken(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
#line 48 "../../asn1/spnego/spnego.cnf"
gssapi_oid_value *next_level_value_lcl;
proto_item *item;
proto_tree *subtree;
tvbuff_t *token_tvb;
int len;
/*
* XXX - what should we do if this OID doesn't match the value
* attached to the frame or conversation? (That would be
* bogus, but that's not impossible - some broken implementation
* might negotiate some security mechanism but put the OID
* for some other security mechanism in GSS_Wrap tokens.)
* Does it matter?
*/
next_level_value_lcl = gssapi_lookup_oid_str(MechType_oid);
/*
* Now dissect the GSS_Wrap token; it's assumed to be in the
* rest of the tvbuff.
*/
item = proto_tree_add_item(tree, hf_spnego_wraptoken, tvb, offset, -1, ENC_NA);
subtree = proto_item_add_subtree(item, ett_spnego_wraptoken);
/*
* Now, we should be able to dispatch after creating a new TVB.
* The subdissector must return the length of the part of the
* token it dissected, so we can return the length of the part
* we (and it) dissected.
*/
token_tvb = tvb_new_subset_remaining(tvb, offset);
if (next_level_value_lcl && next_level_value_lcl->wrap_handle) {
len = call_dissector(next_level_value_lcl->wrap_handle, token_tvb, actx->pinfo,
subtree);
if (len == 0)
offset = tvb_length(tvb);
else
offset = offset + len;
} else
offset = tvb_length(tvb);
return offset;
}
static const ber_sequence_t InitialContextToken_U_sequence[] = {
{ &hf_spnego_thisMech , BER_CLASS_UNI, BER_UNI_TAG_OID, BER_FLAGS_NOOWNTAG, dissect_spnego_MechType },
{ &hf_spnego_innerContextToken, BER_CLASS_ANY, 0, BER_FLAGS_NOOWNTAG, dissect_spnego_InnerContextToken },
{ NULL, 0, 0, 0, NULL }
};
static int
dissect_spnego_InitialContextToken_U(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_sequence(implicit_tag, actx, tree, tvb, offset,
InitialContextToken_U_sequence, hf_index, ett_spnego_InitialContextToken_U);
return offset;
}
static int
dissect_spnego_InitialContextToken(gboolean implicit_tag _U_, tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
offset = dissect_ber_tagged_type(implicit_tag, actx, tree, tvb, offset,
hf_index, BER_CLASS_APP, 0, TRUE, dissect_spnego_InitialContextToken_U);
return offset;
}
/*--- End of included file: packet-spnego-fn.c ---*/
#line 105 "../../asn1/spnego/packet-spnego-template.c"
/*
* This is the SPNEGO KRB5 dissector. It is not true KRB5, but some ASN.1
* wrapped blob with an OID, USHORT token ID, and a Ticket, that is also
* ASN.1 wrapped by the looks of it. It conforms to RFC1964.
*/
#define KRB_TOKEN_AP_REQ 0x0001
#define KRB_TOKEN_AP_REP 0x0002
#define KRB_TOKEN_AP_ERR 0x0003
#define KRB_TOKEN_GETMIC 0x0101
#define KRB_TOKEN_WRAP 0x0102
#define KRB_TOKEN_DELETE_SEC_CONTEXT 0x0201
#define KRB_TOKEN_CFX_GETMIC 0x0404
#define KRB_TOKEN_CFX_WRAP 0x0405
static const value_string spnego_krb5_tok_id_vals[] = {
{ KRB_TOKEN_AP_REQ, "KRB5_AP_REQ"},
{ KRB_TOKEN_AP_REP, "KRB5_AP_REP"},
{ KRB_TOKEN_AP_ERR, "KRB5_ERROR"},
{ KRB_TOKEN_GETMIC, "KRB5_GSS_GetMIC" },
{ KRB_TOKEN_WRAP, "KRB5_GSS_Wrap" },
{ KRB_TOKEN_DELETE_SEC_CONTEXT, "KRB5_GSS_Delete_sec_context" },
{ KRB_TOKEN_CFX_GETMIC, "KRB_TOKEN_CFX_GetMic" },
{ KRB_TOKEN_CFX_WRAP, "KRB_TOKEN_CFX_WRAP" },
{ 0, NULL}
};
#define KRB_SGN_ALG_DES_MAC_MD5 0x0000
#define KRB_SGN_ALG_MD2_5 0x0001
#define KRB_SGN_ALG_DES_MAC 0x0002
#define KRB_SGN_ALG_HMAC 0x0011
static const value_string spnego_krb5_sgn_alg_vals[] = {
{ KRB_SGN_ALG_DES_MAC_MD5, "DES MAC MD5"},
{ KRB_SGN_ALG_MD2_5, "MD2.5"},
{ KRB_SGN_ALG_DES_MAC, "DES MAC"},
{ KRB_SGN_ALG_HMAC, "HMAC"},
{ 0, NULL}
};
#define KRB_SEAL_ALG_DES_CBC 0x0000
#define KRB_SEAL_ALG_RC4 0x0010
#define KRB_SEAL_ALG_NONE 0xffff
static const value_string spnego_krb5_seal_alg_vals[] = {
{ KRB_SEAL_ALG_DES_CBC, "DES CBC"},
{ KRB_SEAL_ALG_RC4, "RC4"},
{ KRB_SEAL_ALG_NONE, "None"},
{ 0, NULL}
};
/*
* XXX - is this for SPNEGO or just GSS-API?
* RFC 1964 is "The Kerberos Version 5 GSS-API Mechanism"; presumably one
* can directly designate Kerberos V5 as a mechanism in GSS-API, rather
* than designating SPNEGO as the mechanism, offering Kerberos V5, and
* getting it accepted.
*/
static int
dissect_spnego_krb5_getmic_base(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int
dissect_spnego_krb5_wrap_base(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree, guint16 token_id);
static int
dissect_spnego_krb5_cfx_getmic_base(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int
dissect_spnego_krb5_cfx_wrap_base(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree, guint16 token_id);
static void
dissect_spnego_krb5(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_item *item;
proto_tree *subtree;
int offset = 0;
guint16 token_id;
const char *oid;
tvbuff_t *krb5_tvb;
gint8 class;
gboolean pc, ind = 0;
gint32 tag;
guint32 len;
asn1_ctx_t asn1_ctx;
asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
item = proto_tree_add_item(tree, hf_spnego_krb5, tvb, offset,
-1, ENC_NA);
subtree = proto_item_add_subtree(item, ett_spnego_krb5);
/*
* The KRB5 blob conforms to RFC1964:
* [APPLICATION 0] {
* OID,
* USHORT (0x0001 == AP-REQ, 0x0002 == AP-REP, 0x0003 == ERROR),
* OCTET STRING }
*
* However, for some protocols, the KRB5 blob starts at the SHORT
* and has no DER encoded header etc.
*
* It appears that for some other protocols the KRB5 blob is just
* a Kerberos message, with no [APPLICATION 0] header, no OID,
* and no USHORT.
*
* So:
*
* If we see an [APPLICATION 0] HEADER, we show the OID and
* the USHORT, and then dissect the rest as a Kerberos message.
*
* If we see an [APPLICATION 14] or [APPLICATION 15] header,
* we assume it's an AP-REQ or AP-REP message, and dissect
* it all as a Kerberos message.
*
* Otherwise, we show the USHORT, and then dissect the rest
* as a Kerberos message.
*/
/*
* Get the first header ...
*/
get_ber_identifier(tvb, offset, &class, &pc, &tag);
if (class == BER_CLASS_APP && pc) {
/*
* [APPLICATION <tag>]
*/
offset = dissect_ber_identifier(pinfo, subtree, tvb, offset, &class, &pc, &tag);
offset = dissect_ber_length(pinfo, subtree, tvb, offset, &len, &ind);
switch (tag) {
case 0:
/*
* [APPLICATION 0]
*/
/* Next, the OID */
offset=dissect_ber_object_identifier_str(FALSE, &asn1_ctx, subtree, tvb, offset, hf_spnego_krb5_oid, &oid);
token_id = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(subtree, hf_spnego_krb5_tok_id, tvb, offset, 2,
token_id);
offset += 2;
break;
case 14: /* [APPLICATION 14] */
case 15: /* [APPLICATION 15] */
/*
* No token ID - just dissect as a Kerberos message and
* return.
*/
dissect_kerberos_main(tvb, pinfo, subtree, FALSE, NULL);
return;
default:
proto_tree_add_text(subtree, tvb, offset, 0,
"Unknown header (class=%d, pc=%d, tag=%d)",
class, pc, tag);
goto done;
}
} else {
/* Next, the token ID ... */
token_id = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(subtree, hf_spnego_krb5_tok_id, tvb, offset, 2,
token_id);
offset += 2;
}
switch (token_id) {
case KRB_TOKEN_AP_REQ:
case KRB_TOKEN_AP_REP:
case KRB_TOKEN_AP_ERR:
krb5_tvb = tvb_new_subset_remaining(tvb, offset);
offset = dissect_kerberos_main(krb5_tvb, pinfo, subtree, FALSE, NULL);
break;
case KRB_TOKEN_GETMIC:
offset = dissect_spnego_krb5_getmic_base(tvb, offset, pinfo, subtree);
break;
case KRB_TOKEN_WRAP:
offset = dissect_spnego_krb5_wrap_base(tvb, offset, pinfo, subtree, token_id);
break;
case KRB_TOKEN_DELETE_SEC_CONTEXT:
break;
case KRB_TOKEN_CFX_GETMIC:
offset = dissect_spnego_krb5_cfx_getmic_base(tvb, offset, pinfo, subtree);
break;
case KRB_TOKEN_CFX_WRAP:
offset = dissect_spnego_krb5_cfx_wrap_base(tvb, offset, pinfo, subtree, token_id);
break;
default:
break;
}
done:
proto_item_set_len(item, offset);
return;
}
#ifdef HAVE_KERBEROS
#include <epan/crypt/md5.h>
#ifndef KEYTYPE_ARCFOUR_56
# define KEYTYPE_ARCFOUR_56 24
#endif
/* XXX - We should probably do a configure-time check for this instead */
#ifndef KRB5_KU_USAGE_SEAL
# define KRB5_KU_USAGE_SEAL 22
#endif
static int
arcfour_mic_key(void *key_data, size_t key_size, int key_type,
void *cksum_data, size_t cksum_size,
void *key6_data)
{
guint8 k5_data[16];
guint8 T[4];
memset(T, 0, 4);
if (key_type == KEYTYPE_ARCFOUR_56) {
guint8 L40[14] = "fortybits";
memcpy(L40 + 10, T, sizeof(T));
md5_hmac(
L40, 14,
key_data,
key_size,
k5_data);
memset(&k5_data[7], 0xAB, 9);
} else {
md5_hmac(
T, 4,
key_data,
key_size,
k5_data);
}
md5_hmac(
cksum_data, cksum_size,
k5_data,
16,
key6_data);
return 0;
}
static int
usage2arcfour(int usage)
{
switch (usage) {
case 3: /*KRB5_KU_AS_REP_ENC_PART 3 */
case 9: /*KRB5_KU_TGS_REP_ENC_PART_SUB_KEY 9 */
return 8;
case 22: /*KRB5_KU_USAGE_SEAL 22 */
return 13;
case 23: /*KRB5_KU_USAGE_SIGN 23 */
return 15;
case 24: /*KRB5_KU_USAGE_SEQ 24 */
return 0;
default :
return 0;
}
}
static int
arcfour_mic_cksum(guint8 *key_data, int key_length,
unsigned int usage,
guint8 sgn_cksum[8],
const void *v1, size_t l1,
const void *v2, size_t l2,
const void *v3, size_t l3)
{
const guint8 signature[] = "signaturekey";
guint8 ksign_c[16];
unsigned char t[4];
md5_state_t ms;
unsigned char digest[16];
int rc4_usage;
guint8 cksum[16];
rc4_usage=usage2arcfour(usage);
md5_hmac(signature, sizeof(signature),
key_data, key_length,
ksign_c);
md5_init(&ms);
t[0] = (rc4_usage >> 0) & 0xFF;
t[1] = (rc4_usage >> 8) & 0xFF;
t[2] = (rc4_usage >> 16) & 0xFF;
t[3] = (rc4_usage >> 24) & 0xFF;
md5_append(&ms, t, 4);
md5_append(&ms, v1, l1);
md5_append(&ms, v2, l2);
md5_append(&ms, v3, l3);
md5_finish(&ms, digest);
md5_hmac(digest, 16, ksign_c, 16, cksum);
memcpy(sgn_cksum, cksum, 8);
return 0;
}
/*
* Verify padding of a gss wrapped message and return its length.
*/
static int
gssapi_verify_pad(unsigned char *wrapped_data, int wrapped_length,
int datalen,
int *padlen)
{
unsigned char *pad;
int padlength;
int i;
pad = wrapped_data + wrapped_length - 1;
padlength = *pad;
if (padlength > datalen)
return 1;
for (i = padlength; i > 0 && *pad == padlength; i--, pad--)
;
if (i != 0)
return 2;
*padlen = padlength;
return 0;
}
static int
decrypt_arcfour(packet_info *pinfo,
guint8 *input_message_buffer,
guint8 *output_message_buffer,
guint8 *key_value, int key_size, int key_type)
{
guint8 Klocaldata[16];
int ret;
int datalen;
guint8 k6_data[16];
guint32 SND_SEQ[2];
guint8 Confounder[8];
guint8 cksum_data[8];
int cmp;
int conf_flag;
int padlen = 0;
datalen = tvb_length(pinfo->gssapi_encrypted_tvb);
if(tvb_get_ntohs(pinfo->gssapi_wrap_tvb, 4)==0x1000){
conf_flag=1;
} else if (tvb_get_ntohs(pinfo->gssapi_wrap_tvb, 4)==0xffff){
conf_flag=0;
} else {
return -3;
}
if(tvb_get_ntohs(pinfo->gssapi_wrap_tvb, 6)!=0xffff){
return -4;
}
ret = arcfour_mic_key(key_value, key_size, key_type,
(void *)tvb_get_ptr(pinfo->gssapi_wrap_tvb, 16, 8),
8, /* SGN_CKSUM */
k6_data);
if (ret) {
return -5;
}
{
rc4_state_struct rc4_state;
crypt_rc4_init(&rc4_state, k6_data, sizeof(k6_data));
tvb_memcpy(pinfo->gssapi_wrap_tvb, SND_SEQ, 8, 8);
crypt_rc4(&rc4_state, (unsigned char *)SND_SEQ, 8);
memset(k6_data, 0, sizeof(k6_data));
}
if (SND_SEQ[1] != 0xFFFFFFFF && SND_SEQ[1] != 0x00000000) {
return -6;
}
{
int i;
for (i = 0; i < 16; i++)
Klocaldata[i] = ((guint8 *)key_value)[i] ^ 0xF0;
}
ret = arcfour_mic_key(Klocaldata,sizeof(Klocaldata),key_type,
(unsigned char *)SND_SEQ, 4,
k6_data);
memset(Klocaldata, 0, sizeof(Klocaldata));
if (ret) {
return -7;
}
if(conf_flag) {
rc4_state_struct rc4_state;
crypt_rc4_init(&rc4_state, k6_data, sizeof(k6_data));
tvb_memcpy(pinfo->gssapi_wrap_tvb, Confounder, 24, 8);
crypt_rc4(&rc4_state, Confounder, 8);
memcpy(output_message_buffer, input_message_buffer, datalen);
crypt_rc4(&rc4_state, output_message_buffer, datalen);
} else {
tvb_memcpy(pinfo->gssapi_wrap_tvb, Confounder, 24, 8);
memcpy(output_message_buffer,
input_message_buffer,
datalen);
}
memset(k6_data, 0, sizeof(k6_data));
/* only normal (i.e. non DCE style wrapping use padding ? */
if(pinfo->decrypt_gssapi_tvb==DECRYPT_GSSAPI_NORMAL){
ret = gssapi_verify_pad(output_message_buffer,datalen,datalen, &padlen);
if (ret) {
return -9;
}
datalen -= padlen;
}
/* dont know what the checksum looks like for dce style gssapi */
if(pinfo->decrypt_gssapi_tvb==DECRYPT_GSSAPI_NORMAL){
ret = arcfour_mic_cksum(key_value, key_size,
KRB5_KU_USAGE_SEAL,
cksum_data,
tvb_get_ptr(pinfo->gssapi_wrap_tvb, 0, 8), 8,
Confounder, sizeof(Confounder),
output_message_buffer,
datalen + padlen);
if (ret) {
return -10;
}
cmp = tvb_memeql(pinfo->gssapi_wrap_tvb, 16, cksum_data, 8); /* SGN_CKSUM */
if (cmp) {
return -11;
}
}
return datalen;
}
#if defined(HAVE_HEIMDAL_KERBEROS) || defined(HAVE_MIT_KERBEROS)
static void
decrypt_gssapi_krb_arcfour_wrap(proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, int keytype)
{
int ret;
enc_key_t *ek;
int length;
const guint8 *original_data;
static int omb_index=0;
static guint8 *omb_arr[4]={NULL,NULL,NULL,NULL};
static guint8 *cryptocopy=NULL; /* workaround for pre-0.6.1 heimdal bug */
guint8 *output_message_buffer;
omb_index++;
if(omb_index>=4){
omb_index=0;
}
output_message_buffer=omb_arr[omb_index];
length=tvb_length(pinfo->gssapi_encrypted_tvb);
original_data=tvb_get_ptr(pinfo->gssapi_encrypted_tvb, 0, length);
/* dont do anything if we are not attempting to decrypt data */
/*
if(!krb_decrypt){
return;
}
*/
/* XXX we should only do this for first time, then store somewhere */
/* XXX We also need to re-read the keytab when the preference changes */
cryptocopy=ep_alloc(length);
if(output_message_buffer){
g_free(output_message_buffer);
output_message_buffer=NULL;
}
output_message_buffer=g_malloc(length);
for(ek=enc_key_list;ek;ek=ek->next){
/* shortcircuit and bail out if enctypes are not matching */
if(ek->keytype!=keytype){
continue;
}
/* pre-0.6.1 versions of Heimdal would sometimes change
the cryptotext data even when the decryption failed.
This would obviously not work since we iterate over the
keys. So just give it a copy of the crypto data instead.
This has been seen for RC4-HMAC blobs.
*/
memcpy(cryptocopy, original_data, length);
ret=decrypt_arcfour(pinfo,
cryptocopy,
output_message_buffer,
ek->keyvalue,
ek->keylength,
ek->keytype
);
if (ret >= 0) {
proto_tree_add_text(tree, NULL, 0, 0, "[Decrypted using: %s]", ek->key_origin);
pinfo->gssapi_decrypted_tvb=tvb_new_child_real_data(tvb,
output_message_buffer,
ret, ret);
tvb_set_free_cb(pinfo->gssapi_decrypted_tvb, g_free);
add_new_data_source(pinfo, pinfo->gssapi_decrypted_tvb, "Decrypted GSS-Krb5");
return;
}
}
return;
}
/* borrowed from heimdal */
static int
rrc_rotate(void *data, int len, guint16 rrc, int unrotate)
{
unsigned char *tmp, buf[256];
size_t left;
if (len == 0)
return 0;
rrc %= len;
if (rrc == 0)
return 0;
left = len - rrc;
if (rrc <= sizeof(buf)) {
tmp = buf;
} else {
tmp = g_malloc(rrc);
if (tmp == NULL)
return -1;
}
if (unrotate) {
memcpy(tmp, data, rrc);
memmove(data, (unsigned char *)data + rrc, left);
memcpy((unsigned char *)data + left, tmp, rrc);
} else {
memcpy(tmp, (unsigned char *)data + left, rrc);
memmove((unsigned char *)data + rrc, data, left);
memcpy(data, tmp, rrc);
}
if (rrc > sizeof(buf))
g_free(tmp);
return 0;
}
#define KRB5_KU_USAGE_ACCEPTOR_SEAL 22
#define KRB5_KU_USAGE_ACCEPTOR_SIGN 23
#define KRB5_KU_USAGE_INITIATOR_SEAL 24
#define KRB5_KU_USAGE_INITIATOR_SIGN 25
static void
decrypt_gssapi_krb_cfx_wrap(proto_tree *tree _U_,
packet_info *pinfo,
tvbuff_t *checksum_tvb,
tvbuff_t *encrypted_tvb,
guint16 ec,
guint16 rrc,
gboolean is_dce,
int keytype,
unsigned int usage)
{
guint8 *rotated;
guint8 *output;
int datalen;
tvbuff_t *next_tvb;
/* dont do anything if we are not attempting to decrypt data */
if(!krb_decrypt){
return;
}
datalen = tvb_length(checksum_tvb) + tvb_length(encrypted_tvb);
rotated = g_malloc(datalen);
tvb_memcpy(checksum_tvb, rotated,
0, tvb_length(checksum_tvb));
tvb_memcpy(encrypted_tvb, rotated + tvb_length(checksum_tvb),
0, tvb_length(encrypted_tvb));
if (is_dce) {
rrc += ec;
}
rrc_rotate(rotated, datalen, rrc, TRUE);
next_tvb=tvb_new_child_real_data(encrypted_tvb, rotated,
datalen, datalen);
tvb_set_free_cb(next_tvb, g_free);
add_new_data_source(pinfo, next_tvb, "GSSAPI CFX");
output = decrypt_krb5_data(tree, pinfo, usage, next_tvb,
keytype, &datalen);
if (output) {
guint8 *outdata;
outdata = g_memdup(output, tvb_length(encrypted_tvb));
g_free(output);
pinfo->gssapi_decrypted_tvb=tvb_new_child_real_data(encrypted_tvb,
outdata,
tvb_length(encrypted_tvb),
tvb_length(encrypted_tvb));
add_new_data_source(pinfo, pinfo->gssapi_decrypted_tvb, "Decrypted GSS-Krb5");
tvb_set_free_cb(pinfo->gssapi_decrypted_tvb, g_free);
return;
}
return;
}
#endif /* HAVE_HEIMDAL_KERBEROS || HAVE_MIT_KERBEROS */
#endif
/*
* This is for GSSAPI Wrap tokens ...
*/
static int
dissect_spnego_krb5_wrap_base(tvbuff_t *tvb, int offset, packet_info *pinfo
#ifndef HAVE_KERBEROS
_U_
#endif
, proto_tree *tree, guint16 token_id
#ifndef HAVE_KERBEROS
_U_
#endif
)
{
guint16 sgn_alg, seal_alg;
#ifdef HAVE_KERBEROS
int start_offset=offset;
#endif
/*
* The KRB5 blob conforms to RFC1964:
* USHORT (0x0102 == GSS_Wrap)
* and so on }
*/
/* Now, the sign and seal algorithms ... */
sgn_alg = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(tree, hf_spnego_krb5_sgn_alg, tvb, offset, 2,
sgn_alg);
offset += 2;
seal_alg = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(tree, hf_spnego_krb5_seal_alg, tvb, offset, 2,
seal_alg);
offset += 2;
/* Skip the filler */
offset += 2;
/* Encrypted sequence number */
proto_tree_add_item(tree, hf_spnego_krb5_snd_seq, tvb, offset, 8,
ENC_NA);
offset += 8;
/* Checksum of plaintext padded data */
proto_tree_add_item(tree, hf_spnego_krb5_sgn_cksum, tvb, offset, 8,
ENC_NA);
offset += 8;
/*
* At least according to draft-brezak-win2k-krb-rc4-hmac-04,
* if the signing algorithm is KRB_SGN_ALG_HMAC, there's an
* extra 8 bytes of "Random confounder" after the checksum.
* It certainly confounds code expecting all Kerberos 5
* GSS_Wrap() tokens to look the same....
*/
if ((sgn_alg == KRB_SGN_ALG_HMAC) ||
/* there also seems to be a confounder for DES MAC MD5 - certainly seen when using with
SASL with LDAP between a Java client and Active Directory. If this breaks other things
we may need to make this an option. gal 17/2/06 */
(sgn_alg == KRB_SGN_ALG_DES_MAC_MD5)) {
proto_tree_add_item(tree, hf_spnego_krb5_confounder, tvb, offset, 8,
ENC_NA);
offset += 8;
}
/* Is the data encrypted? */
pinfo->gssapi_data_encrypted=(seal_alg!=KRB_SEAL_ALG_NONE);
#ifdef HAVE_KERBEROS
#define GSS_ARCFOUR_WRAP_TOKEN_SIZE 32
if(pinfo->decrypt_gssapi_tvb){
/* if the caller did not provide a tvb, then we just use
whatever is left of our current tvb.
*/
if(!pinfo->gssapi_encrypted_tvb){
int len;
len=tvb_reported_length_remaining(tvb,offset);
if(len>tvb_length_remaining(tvb, offset)){
/* no point in trying to decrypt,
we dont have the full pdu.
*/
return offset;
}
pinfo->gssapi_encrypted_tvb = tvb_new_subset(
tvb, offset, len, len);
}
/* if this is KRB5 wrapped rc4-hmac */
if((token_id==KRB_TOKEN_WRAP)
&&(sgn_alg==KRB_SGN_ALG_HMAC)
&&(seal_alg==KRB_SEAL_ALG_RC4)){
/* do we need to create a tvb for the wrapper
as well ?
*/
if(!pinfo->gssapi_wrap_tvb){
pinfo->gssapi_wrap_tvb = tvb_new_subset(
tvb, start_offset-2,
GSS_ARCFOUR_WRAP_TOKEN_SIZE,
GSS_ARCFOUR_WRAP_TOKEN_SIZE);
}
#if defined(HAVE_HEIMDAL_KERBEROS) || defined(HAVE_MIT_KERBEROS)
decrypt_gssapi_krb_arcfour_wrap(tree,
pinfo,
tvb,
23 /* rc4-hmac */);
#endif /* HAVE_HEIMDAL_KERBEROS || HAVE_MIT_KERBEROS */
}
}
#endif
/*
* Return the offset past the checksum, so that we know where
* the data we're wrapped around starts. Also, set the length
* of our top-level item to that offset, so it doesn't cover
* the data we're wrapped around.
*
* Note that for DCERPC the GSSAPI blobs comes after the data it wraps,
* not before.
*/
return offset;
}
/*
* XXX - This is for GSSAPI GetMIC tokens ...
*/
static int
dissect_spnego_krb5_getmic_base(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
{
guint16 sgn_alg;
/*
* The KRB5 blob conforms to RFC1964:
* USHORT (0x0101 == GSS_GetMIC)
* and so on }
*/
/* Now, the sign algorithm ... */
sgn_alg = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(tree, hf_spnego_krb5_sgn_alg, tvb, offset, 2,
sgn_alg);
offset += 2;
/* Skip the filler */
offset += 4;
/* Encrypted sequence number */
proto_tree_add_item(tree, hf_spnego_krb5_snd_seq, tvb, offset, 8,
ENC_NA);
offset += 8;
/* Checksum of plaintext padded data */
proto_tree_add_item(tree, hf_spnego_krb5_sgn_cksum, tvb, offset, 8,
ENC_NA);
offset += 8;
/*
* At least according to draft-brezak-win2k-krb-rc4-hmac-04,
* if the signing algorithm is KRB_SGN_ALG_HMAC, there's an
* extra 8 bytes of "Random confounder" after the checksum.
* It certainly confounds code expecting all Kerberos 5
* GSS_Wrap() tokens to look the same....
*
* The exception is DNS/TSIG where there is no such confounder
* so we need to test here if there are more bytes in our tvb or not.
* -- ronnie
*/
if (tvb_length_remaining(tvb, offset)) {
if (sgn_alg == KRB_SGN_ALG_HMAC) {
proto_tree_add_item(tree, hf_spnego_krb5_confounder, tvb, offset, 8,
ENC_NA);
offset += 8;
}
}
/*
* Return the offset past the checksum, so that we know where
* the data we're wrapped around starts. Also, set the length
* of our top-level item to that offset, so it doesn't cover
* the data we're wrapped around.
*/
return offset;
}
static int
dissect_spnego_krb5_cfx_flags(tvbuff_t *tvb, int offset,
proto_tree *spnego_krb5_tree,
guint8 cfx_flags)
{
proto_tree *cfx_flags_tree = NULL;
proto_item *tf = NULL;
if (spnego_krb5_tree) {
tf = proto_tree_add_uint(spnego_krb5_tree,
hf_spnego_krb5_cfx_flags,
tvb, offset, 1, cfx_flags);
cfx_flags_tree = proto_item_add_subtree(tf, ett_spnego_krb5_cfx_flags);
}
proto_tree_add_boolean(cfx_flags_tree,
hf_spnego_krb5_cfx_flags_04,
tvb, offset, 1, cfx_flags);
proto_tree_add_boolean(cfx_flags_tree,
hf_spnego_krb5_cfx_flags_02,
tvb, offset, 1, cfx_flags);
proto_tree_add_boolean(cfx_flags_tree,
hf_spnego_krb5_cfx_flags_01,
tvb, offset, 1, cfx_flags);
return (offset + 1);
}
/*
* This is for GSSAPI CFX Wrap tokens ...
*/
static int
dissect_spnego_krb5_cfx_wrap_base(tvbuff_t *tvb, int offset, packet_info *pinfo
#ifndef HAVE_KERBEROS
_U_
#endif
, proto_tree *tree, guint16 token_id _U_
)
{
guint8 flags;
guint16 ec;
#if defined(HAVE_HEIMDAL_KERBEROS) || defined(HAVE_MIT_KERBEROS)
guint16 rrc;
#endif
int checksum_size;
int start_offset=offset;
/*
* The KRB5 blob conforms to RFC4121:
* USHORT (0x0504)
* and so on }
*/
/* Now, the sign and seal algorithms ... */
flags = tvb_get_guint8(tvb, offset);
offset = dissect_spnego_krb5_cfx_flags(tvb, offset, tree, flags);
pinfo->gssapi_data_encrypted=(flags & 2);
/* Skip the filler */
proto_tree_add_item(tree, hf_spnego_krb5_filler, tvb, offset, 1,
ENC_NA);
offset += 1;
/* EC */
ec = tvb_get_ntohs(tvb, offset);
proto_tree_add_item(tree, hf_spnego_krb5_cfx_ec, tvb, offset, 2,
ENC_BIG_ENDIAN);
offset += 2;
/* RRC */
#if defined(HAVE_HEIMDAL_KERBEROS) || defined(HAVE_MIT_KERBEROS)
rrc = tvb_get_ntohs(tvb, offset);
#endif
proto_tree_add_item(tree, hf_spnego_krb5_cfx_rrc, tvb, offset, 2,
ENC_BIG_ENDIAN);
offset += 2;
/* sequence number */
proto_tree_add_item(tree, hf_spnego_krb5_cfx_seq, tvb, offset, 8,
ENC_BIG_ENDIAN);
offset += 8;
/* Checksum of plaintext padded data */
if (pinfo->gssapi_data_encrypted) {
checksum_size = 44 + ec;
} else {
checksum_size = 12;
}
proto_tree_add_item(tree, hf_spnego_krb5_sgn_cksum, tvb, offset,
checksum_size, ENC_NA);
offset += checksum_size;
if(pinfo->decrypt_gssapi_tvb){
/* if the caller did not provide a tvb, then we just use
whatever is left of our current tvb.
*/
if(!pinfo->gssapi_encrypted_tvb){
int len;
len=tvb_reported_length_remaining(tvb,offset);
if(len>tvb_length_remaining(tvb, offset)){
/* no point in trying to decrypt,
we dont have the full pdu.
*/
return offset;
}
pinfo->gssapi_encrypted_tvb = tvb_new_subset(
tvb, offset, len, len);
}
if (pinfo->gssapi_data_encrypted) {
/* do we need to create a tvb for the wrapper
as well ?
*/
if(!pinfo->gssapi_wrap_tvb){
pinfo->gssapi_wrap_tvb = tvb_new_subset(
tvb, start_offset-2,
offset - (start_offset-2),
offset - (start_offset-2));
}
}
}
#if defined(HAVE_HEIMDAL_KERBEROS) || defined(HAVE_MIT_KERBEROS)
{
tvbuff_t *checksum_tvb = tvb_new_subset(tvb, 16, checksum_size, checksum_size);
if (pinfo->gssapi_data_encrypted) {
if(pinfo->gssapi_encrypted_tvb){
decrypt_gssapi_krb_cfx_wrap(tree,
pinfo,
checksum_tvb,
pinfo->gssapi_encrypted_tvb,
ec,
rrc,
(pinfo->decrypt_gssapi_tvb==DECRYPT_GSSAPI_DCE)?TRUE:FALSE,
-1,
(flags & 0x0001)?
KRB5_KU_USAGE_ACCEPTOR_SEAL:
KRB5_KU_USAGE_INITIATOR_SEAL);
}
}
}
#endif /* HAVE_HEIMDAL_KERBEROS || HAVE_MIT_KERBEROS */
/*
* Return the offset past the checksum, so that we know where
* the data we're wrapped around starts. Also, set the length
* of our top-level item to that offset, so it doesn't cover
* the data we're wrapped around.
*
* Note that for DCERPC the GSSAPI blobs comes after the data it wraps,
* not before.
*/
return offset;
}
/*
* XXX - This is for GSSAPI CFX GetMIC tokens ...
*/
static int
dissect_spnego_krb5_cfx_getmic_base(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
{
guint8 flags;
int checksum_size;
/*
* The KRB5 blob conforms to RFC4121:
* USHORT (0x0404 == GSS_GetMIC)
* and so on }
*/
flags = tvb_get_guint8(tvb, offset);
offset = dissect_spnego_krb5_cfx_flags(tvb, offset, tree, flags);
/* Skip the filler */
proto_tree_add_item(tree, hf_spnego_krb5_filler, tvb, offset, 5,
ENC_NA);
offset += 5;
/* sequence number */
proto_tree_add_item(tree, hf_spnego_krb5_cfx_seq, tvb, offset, 8,
ENC_BIG_ENDIAN);
offset += 8;
/* Checksum of plaintext padded data */
checksum_size = tvb_length_remaining(tvb, offset);
proto_tree_add_item(tree, hf_spnego_krb5_sgn_cksum, tvb, offset,
checksum_size, ENC_NA);
offset += checksum_size;
/*
* Return the offset past the checksum, so that we know where
* the data we're wrapped around starts. Also, set the length
* of our top-level item to that offset, so it doesn't cover
* the data we're wrapped around.
*/
return offset;
}
/*
* XXX - is this for SPNEGO or just GSS-API?
* RFC 1964 is "The Kerberos Version 5 GSS-API Mechanism"; presumably one
* can directly designate Kerberos V5 as a mechanism in GSS-API, rather
* than designating SPNEGO as the mechanism, offering Kerberos V5, and
* getting it accepted.
*/
static int
dissect_spnego_krb5_wrap(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, void *data _U_)
{
proto_item *item;
proto_tree *subtree;
int offset = 0;
guint16 token_id;
item = proto_tree_add_item(tree, hf_spnego_krb5, tvb, 0, -1, ENC_NA);
subtree = proto_item_add_subtree(item, ett_spnego_krb5);
/*
* The KRB5 blob conforms to RFC1964:
* USHORT (0x0102 == GSS_Wrap)
* and so on }
*/
/* First, the token ID ... */
token_id = tvb_get_letohs(tvb, offset);
proto_tree_add_uint(subtree, hf_spnego_krb5_tok_id, tvb, offset, 2,
token_id);
offset += 2;
switch (token_id) {
case KRB_TOKEN_GETMIC:
offset = dissect_spnego_krb5_getmic_base(tvb, offset, pinfo, subtree);
break;
case KRB_TOKEN_WRAP:
offset = dissect_spnego_krb5_wrap_base(tvb, offset, pinfo, subtree, token_id);
break;
case KRB_TOKEN_CFX_GETMIC:
offset = dissect_spnego_krb5_cfx_getmic_base(tvb, offset, pinfo, subtree);
break;
case KRB_TOKEN_CFX_WRAP:
offset = dissect_spnego_krb5_cfx_wrap_base(tvb, offset, pinfo, subtree, token_id);
break;
default:
break;
}
/*
* Return the offset past the checksum, so that we know where
* the data we're wrapped around starts. Also, set the length
* of our top-level item to that offset, so it doesn't cover
* the data we're wrapped around.
*/
proto_item_set_len(item, offset);
return offset;
}
/* Spnego stuff from here */
static int
dissect_spnego_wrap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
proto_item *item;
proto_tree *subtree;
int offset = 0;
asn1_ctx_t asn1_ctx;
asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
MechType_oid = NULL;
/*
* We need this later, so lets get it now ...
* It has to be per-frame as there can be more than one GSS-API
* negotiation in a conversation.
*/
item = proto_tree_add_item(tree, proto_spnego, tvb, offset,
-1, ENC_NA);
subtree = proto_item_add_subtree(item, ett_spnego);
/*
* The TVB contains a [0] header and a sequence that consists of an
* object ID and a blob containing the data ...
* XXX - is this RFC 2743's "Mechanism-Independent Token Format",
* with the "optional" "use in non-initial tokens" being chosen.
* ASN1 code addet to spnego.asn to handle this.
*/
offset = dissect_spnego_InitialContextToken(FALSE, tvb, offset, &asn1_ctx , subtree, -1);
return offset;
}
static void
dissect_spnego(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree)
{
proto_item *item;
proto_tree *subtree;
int offset = 0;
conversation_t *conversation;
asn1_ctx_t asn1_ctx;
asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
/*
* We need this later, so lets get it now ...
* It has to be per-frame as there can be more than one GSS-API
* negotiation in a conversation.
*/
next_level_value = p_get_proto_data(pinfo->fd, proto_spnego);
if (!next_level_value && !pinfo->fd->flags.visited) {
/*
* No handle attached to this frame, but it's the first
* pass, so it'd be attached to the conversation.
* If we have a conversation, try to get the handle,
* and if we get one, attach it to the frame.
*/
conversation = find_conversation(pinfo->fd->num, &pinfo->src, &pinfo->dst,
pinfo->ptype, pinfo->srcport,
pinfo->destport, 0);
if (conversation) {
next_level_value = conversation_get_proto_data(conversation,
proto_spnego);
if (next_level_value)
p_add_proto_data(pinfo->fd, proto_spnego, next_level_value);
}
}
item = proto_tree_add_item(parent_tree, proto_spnego, tvb, offset,
-1, ENC_NA);
subtree = proto_item_add_subtree(item, ett_spnego);
/*
* The TVB contains a [0] header and a sequence that consists of an
* object ID and a blob containing the data ...
* Actually, it contains, according to RFC2478:
* NegotiationToken ::= CHOICE {
* negTokenInit [0] NegTokenInit,
* negTokenTarg [1] NegTokenTarg }
* NegTokenInit ::= SEQUENCE {
* mechTypes [0] MechTypeList OPTIONAL,
* reqFlags [1] ContextFlags OPTIONAL,
* mechToken [2] OCTET STRING OPTIONAL,
* mechListMIC [3] OCTET STRING OPTIONAL }
* NegTokenTarg ::= SEQUENCE {
* negResult [0] ENUMERATED {
* accept_completed (0),
* accept_incomplete (1),
* reject (2) } OPTIONAL,
* supportedMech [1] MechType OPTIONAL,
* responseToken [2] OCTET STRING OPTIONAL,
* mechListMIC [3] OCTET STRING OPTIONAL }
*
* Windows typically includes mechTypes and mechListMic ('NONE'
* in the case of NTLMSSP only).
* It seems to duplicate the responseToken into the mechListMic field
* as well. Naughty, naughty.
*
*/
offset = dissect_spnego_NegotiationToken(FALSE, tvb, offset, &asn1_ctx, subtree, -1);
}
/*--- proto_register_spnego -------------------------------------------*/
void proto_register_spnego(void) {
/* List of fields */
static hf_register_info hf[] = {
{ &hf_spnego_wraptoken,
{ "wrapToken", "spnego.wraptoken",
FT_NONE, BASE_NONE, NULL, 0x0, "SPNEGO wrapToken",
HFILL}},
{ &hf_spnego_krb5,
{ "krb5_blob", "spnego.krb5.blob", FT_BYTES,
BASE_NONE, NULL, 0, NULL, HFILL }},
{ &hf_spnego_krb5_oid,
{ "KRB5 OID", "spnego.krb5_oid", FT_STRING,
BASE_NONE, NULL, 0, NULL, HFILL }},
{ &hf_spnego_krb5_tok_id,
{ "krb5_tok_id", "spnego.krb5.tok_id", FT_UINT16, BASE_HEX,
VALS(spnego_krb5_tok_id_vals), 0, "KRB5 Token Id", HFILL}},
{ &hf_spnego_krb5_sgn_alg,
{ "krb5_sgn_alg", "spnego.krb5.sgn_alg", FT_UINT16, BASE_HEX,
VALS(spnego_krb5_sgn_alg_vals), 0, "KRB5 Signing Algorithm", HFILL}},
{ &hf_spnego_krb5_seal_alg,
{ "krb5_seal_alg", "spnego.krb5.seal_alg", FT_UINT16, BASE_HEX,
VALS(spnego_krb5_seal_alg_vals), 0, "KRB5 Sealing Algorithm", HFILL}},
{ &hf_spnego_krb5_snd_seq,
{ "krb5_snd_seq", "spnego.krb5.snd_seq", FT_BYTES, BASE_NONE,
NULL, 0, "KRB5 Encrypted Sequence Number", HFILL}},
{ &hf_spnego_krb5_sgn_cksum,
{ "krb5_sgn_cksum", "spnego.krb5.sgn_cksum", FT_BYTES, BASE_NONE,
NULL, 0, "KRB5 Data Checksum", HFILL}},
{ &hf_spnego_krb5_confounder,
{ "krb5_confounder", "spnego.krb5.confounder", FT_BYTES, BASE_NONE,
NULL, 0, "KRB5 Confounder", HFILL}},
{ &hf_spnego_krb5_filler,
{ "krb5_filler", "spnego.krb5.filler", FT_BYTES, BASE_NONE,
NULL, 0, "KRB5 Filler", HFILL}},
{ &hf_spnego_krb5_cfx_flags,
{ "krb5_cfx_flags", "spnego.krb5.cfx_flags", FT_UINT8, BASE_HEX,
NULL, 0, "KRB5 CFX Flags", HFILL}},
{ &hf_spnego_krb5_cfx_flags_01,
{ "SendByAcceptor", "spnego.krb5.send_by_acceptor", FT_BOOLEAN, 8,
TFS (&tfs_set_notset), 0x01, NULL, HFILL}},
{ &hf_spnego_krb5_cfx_flags_02,
{ "Sealed", "spnego.krb5.sealed", FT_BOOLEAN, 8,
TFS (&tfs_set_notset), 0x02, NULL, HFILL}},
{ &hf_spnego_krb5_cfx_flags_04,
{ "AcceptorSubkey", "spnego.krb5.acceptor_subkey", FT_BOOLEAN, 8,
TFS (&tfs_set_notset), 0x04, NULL, HFILL}},
{ &hf_spnego_krb5_cfx_ec,
{ "krb5_cfx_ec", "spnego.krb5.cfx_ec", FT_UINT16, BASE_DEC,
NULL, 0, "KRB5 CFX Extra Count", HFILL}},
{ &hf_spnego_krb5_cfx_rrc,
{ "krb5_cfx_rrc", "spnego.krb5.cfx_rrc", FT_UINT16, BASE_DEC,
NULL, 0, "KRB5 CFX Right Rotation Count", HFILL}},
{ &hf_spnego_krb5_cfx_seq,
{ "krb5_cfx_seq", "spnego.krb5.cfx_seq", FT_UINT64, BASE_DEC,
NULL, 0, "KRB5 Sequence Number", HFILL}},
/*--- Included file: packet-spnego-hfarr.c ---*/
#line 1 "../../asn1/spnego/packet-spnego-hfarr.c"
{ &hf_spnego_negTokenInit,
{ "negTokenInit", "spnego.negTokenInit",
FT_NONE, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_negTokenTarg,
{ "negTokenTarg", "spnego.negTokenTarg",
FT_NONE, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_MechTypeList_item,
{ "MechType", "spnego.MechType",
FT_OID, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_principal,
{ "principal", "spnego.principal",
FT_STRING, BASE_NONE, NULL, 0,
"GeneralString", HFILL }},
{ &hf_spnego_mechTypes,
{ "mechTypes", "spnego.mechTypes",
FT_UINT32, BASE_DEC, NULL, 0,
"MechTypeList", HFILL }},
{ &hf_spnego_reqFlags,
{ "reqFlags", "spnego.reqFlags",
FT_BYTES, BASE_NONE, NULL, 0,
"ContextFlags", HFILL }},
{ &hf_spnego_mechToken,
{ "mechToken", "spnego.mechToken",
FT_BYTES, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_negTokenInit_mechListMIC,
{ "mechListMIC", "spnego.mechListMIC",
FT_BYTES, BASE_NONE, NULL, 0,
"T_NegTokenInit_mechListMIC", HFILL }},
{ &hf_spnego_negResult,
{ "negResult", "spnego.negResult",
FT_UINT32, BASE_DEC, VALS(spnego_T_negResult_vals), 0,
NULL, HFILL }},
{ &hf_spnego_supportedMech,
{ "supportedMech", "spnego.supportedMech",
FT_OID, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_responseToken,
{ "responseToken", "spnego.responseToken",
FT_BYTES, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_mechListMIC,
{ "mechListMIC", "spnego.mechListMIC",
FT_BYTES, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_thisMech,
{ "thisMech", "spnego.thisMech",
FT_OID, BASE_NONE, NULL, 0,
"MechType", HFILL }},
{ &hf_spnego_innerContextToken,
{ "innerContextToken", "spnego.innerContextToken",
FT_NONE, BASE_NONE, NULL, 0,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_delegFlag,
{ "delegFlag", "spnego.delegFlag",
FT_BOOLEAN, 8, NULL, 0x80,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_mutualFlag,
{ "mutualFlag", "spnego.mutualFlag",
FT_BOOLEAN, 8, NULL, 0x40,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_replayFlag,
{ "replayFlag", "spnego.replayFlag",
FT_BOOLEAN, 8, NULL, 0x20,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_sequenceFlag,
{ "sequenceFlag", "spnego.sequenceFlag",
FT_BOOLEAN, 8, NULL, 0x10,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_anonFlag,
{ "anonFlag", "spnego.anonFlag",
FT_BOOLEAN, 8, NULL, 0x08,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_confFlag,
{ "confFlag", "spnego.confFlag",
FT_BOOLEAN, 8, NULL, 0x04,
NULL, HFILL }},
{ &hf_spnego_ContextFlags_integFlag,
{ "integFlag", "spnego.integFlag",
FT_BOOLEAN, 8, NULL, 0x02,
NULL, HFILL }},
/*--- End of included file: packet-spnego-hfarr.c ---*/
#line 1391 "../../asn1/spnego/packet-spnego-template.c"
};
/* List of subtrees */
static gint *ett[] = {
&ett_spnego,
&ett_spnego_wraptoken,
&ett_spnego_krb5,
&ett_spnego_krb5_cfx_flags,
/*--- Included file: packet-spnego-ettarr.c ---*/
#line 1 "../../asn1/spnego/packet-spnego-ettarr.c"
&ett_spnego_NegotiationToken,
&ett_spnego_MechTypeList,
&ett_spnego_PrincipalSeq,
&ett_spnego_NegTokenInit,
&ett_spnego_ContextFlags,
&ett_spnego_NegTokenTarg,
&ett_spnego_InitialContextToken_U,
/*--- End of included file: packet-spnego-ettarr.c ---*/
#line 1401 "../../asn1/spnego/packet-spnego-template.c"
};
/* Register protocol */
proto_spnego = proto_register_protocol(PNAME, PSNAME, PFNAME);
register_dissector("spnego", dissect_spnego, proto_spnego);
proto_spnego_krb5 = proto_register_protocol("SPNEGO-KRB5",
"SPNEGO-KRB5",
"spnego-krb5");
register_dissector("spnego-krb5", dissect_spnego_krb5, proto_spnego_krb5);
new_register_dissector("spnego-krb5-wrap", dissect_spnego_krb5_wrap, proto_spnego_krb5);
/* Register fields and subtrees */
proto_register_field_array(proto_spnego, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
/*--- proto_reg_handoff_spnego ---------------------------------------*/
void proto_reg_handoff_spnego(void) {
dissector_handle_t spnego_handle, spnego_wrap_handle;
dissector_handle_t spnego_krb5_handle, spnego_krb5_wrap_handle;
/* Register protocol with GSS-API module */
spnego_handle = find_dissector("spnego");
spnego_wrap_handle = new_create_dissector_handle(dissect_spnego_wrap, proto_spnego);
gssapi_init_oid("1.3.6.1.5.5.2", proto_spnego, ett_spnego,
spnego_handle, spnego_wrap_handle,
"SPNEGO - Simple Protected Negotiation");
/* Register both the one MS created and the real one */
/*
* Thanks to Jean-Baptiste Marchand and Richard B Ward, the
* mystery of the MS KRB5 OID is cleared up. It was due to a library
* that did not handle OID components greater than 16 bits, and was
* fixed in Win2K SP2 as well as WinXP.
* See the archive of <ietf-krb-wg@anl.gov> for the thread topic
* SPNEGO implementation issues. 3-Dec-2002.
*/
spnego_krb5_handle = find_dissector("spnego-krb5");
spnego_krb5_wrap_handle = find_dissector("spnego-krb5-wrap");
gssapi_init_oid("1.2.840.48018.1.2.2", proto_spnego_krb5, ett_spnego_krb5,
spnego_krb5_handle, spnego_krb5_wrap_handle,
"MS KRB5 - Microsoft Kerberos 5");
gssapi_init_oid("1.2.840.113554.1.2.2", proto_spnego_krb5, ett_spnego_krb5,
spnego_krb5_handle, spnego_krb5_wrap_handle,
"KRB5 - Kerberos 5");
gssapi_init_oid("1.2.840.113554.1.2.2.3", proto_spnego_krb5, ett_spnego_krb5,
spnego_krb5_handle, spnego_krb5_wrap_handle,
"KRB5 - Kerberos 5 - User to User");
}
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