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/*
Unix SMB/CIFS implementation.
raw dcerpc operations
Copyright (C) Andrew Tridgell 2003-2005
Copyright (C) Jelmer Vernooij 2004-2005
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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "librpc/rpc/dcerpc.h"
#include "librpc/gen_ndr/ndr_dcerpc.h"
/* we need to be able to get/set the fragment length without doing a full
decode */
void dcerpc_set_frag_length(DATA_BLOB *blob, uint16_t v)
{
if (CVAL(blob->data,DCERPC_DREP_OFFSET) & DCERPC_DREP_LE) {
SSVAL(blob->data, DCERPC_FRAG_LEN_OFFSET, v);
} else {
RSSVAL(blob->data, DCERPC_FRAG_LEN_OFFSET, v);
}
}
uint16_t dcerpc_get_frag_length(const DATA_BLOB *blob)
{
if (CVAL(blob->data,DCERPC_DREP_OFFSET) & DCERPC_DREP_LE) {
return SVAL(blob->data, DCERPC_FRAG_LEN_OFFSET);
} else {
return RSVAL(blob->data, DCERPC_FRAG_LEN_OFFSET);
}
}
void dcerpc_set_auth_length(DATA_BLOB *blob, uint16_t v)
{
if (CVAL(blob->data,DCERPC_DREP_OFFSET) & DCERPC_DREP_LE) {
SSVAL(blob->data, DCERPC_AUTH_LEN_OFFSET, v);
} else {
RSSVAL(blob->data, DCERPC_AUTH_LEN_OFFSET, v);
}
}
uint8_t dcerpc_get_endian_flag(DATA_BLOB *blob)
{
return blob->data[DCERPC_DREP_OFFSET];
}
/**
* @brief Pull a dcerpc_auth structure, taking account of any auth
* padding in the blob. For request/response packets we pass
* the whole data blob, so auth_data_only must be set to false
* as the blob contains data+pad+auth and no just pad+auth.
*
* @param pkt - The ncacn_packet strcuture
* @param mem_ctx - The mem_ctx used to allocate dcerpc_auth elements
* @param pkt_trailer - The packet trailer data, usually the trailing
* auth_info blob, but in the request/response case
* this is the stub_and_verifier blob.
* @param auth - A preallocated dcerpc_auth *empty* structure
* @param auth_length - The length of the auth trail, sum of auth header
* lenght and pkt->auth_length
* @param auth_data_only - Whether the pkt_trailer includes only the auth_blob
* (+ padding) or also other data.
*
* @return - A NTSTATUS error code.
*/
NTSTATUS dcerpc_pull_auth_trailer(struct ncacn_packet *pkt,
TALLOC_CTX *mem_ctx,
DATA_BLOB *pkt_trailer,
struct dcerpc_auth *auth,
uint32_t *auth_length,
bool auth_data_only)
{
struct ndr_pull *ndr;
enum ndr_err_code ndr_err;
uint32_t data_and_pad;
data_and_pad = pkt_trailer->length
- (DCERPC_AUTH_TRAILER_LENGTH + pkt->auth_length);
/* paranoia check for pad size. This would be caught anyway by
the ndr_pull_advance() a few lines down, but it scared
Jeremy enough for him to call me, so we might as well check
it now, just to prevent someone posting a bogus YouTube
video in the future.
*/
if (data_and_pad > pkt_trailer->length) {
return NT_STATUS_INFO_LENGTH_MISMATCH;
}
*auth_length = pkt_trailer->length - data_and_pad;
ndr = ndr_pull_init_blob(pkt_trailer, mem_ctx);
if (!ndr) {
return NT_STATUS_NO_MEMORY;
}
if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
}
ndr_err = ndr_pull_advance(ndr, data_and_pad);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
talloc_free(ndr);
return ndr_map_error2ntstatus(ndr_err);
}
ndr_err = ndr_pull_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, auth);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
talloc_free(ndr);
return ndr_map_error2ntstatus(ndr_err);
}
if (auth_data_only && data_and_pad != auth->auth_pad_length) {
DEBUG(1, (__location__ ": WARNING: pad length mismatch. "
"Calculated %u got %u\n",
(unsigned)data_and_pad,
(unsigned)auth->auth_pad_length));
}
DEBUG(6,(__location__ ": auth_pad_length %u\n",
(unsigned)auth->auth_pad_length));
talloc_steal(mem_ctx, auth->credentials.data);
talloc_free(ndr);
return NT_STATUS_OK;
}
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