/*
* Off-the-Record Messaging library
* Copyright (C) 2004-2012 Ian Goldberg, Chris Alexander, Willy Lew,
* Nikita Borisov
* <otr@cypherpunks.ca>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of version 2.1 of the GNU Lesser General
* Public License as published by the Free Software Foundation.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __TLV_H__
#define __TLV_H__
typedef struct s_OtrlTLV {
unsigned short type;
unsigned short len;
unsigned char *data;
struct s_OtrlTLV *next;
} OtrlTLV;
/* TLV types */
/* This is just padding for the encrypted message, and should be ignored. */
#define OTRL_TLV_PADDING 0x0000
/* The sender has thrown away his OTR session keys with you */
#define OTRL_TLV_DISCONNECTED 0x0001
/* The message contains a step in the Socialist Millionaires' Protocol. */
#define OTRL_TLV_SMP1 0x0002
#define OTRL_TLV_SMP2 0x0003
#define OTRL_TLV_SMP3 0x0004
#define OTRL_TLV_SMP4 0x0005
#define OTRL_TLV_SMP_ABORT 0x0006
/* Like OTRL_TLV_SMP1, but there's a question for the buddy at the
* beginning */
#define OTRL_TLV_SMP1Q 0x0007
/* Tell the application the current "extra" symmetric key */
/* XXX: Document this in the protocol spec:
* The body of the TLV will begin with a 4-byte indication of what this
* symmetric key will be used for (file transfer, voice encryption,
* etc.). After that, the contents are use-specific (which file, etc.).
* There are no currently defined uses. */
#define OTRL_TLV_SYMKEY 0x0008
/* Make a single TLV, copying the supplied data */
OtrlTLV *otrl_tlv_new(unsigned short type, unsigned short len,
const unsigned char *data);
/* Construct a chain of TLVs from the given data */
OtrlTLV *otrl_tlv_parse(const unsigned char *serialized, size_t seriallen);
/* Deallocate a chain of TLVs */
void otrl_tlv_free(OtrlTLV *tlv);
/* Find the serialized length of a chain of TLVs */
size_t otrl_tlv_seriallen(const OtrlTLV *tlv);
/* Serialize a chain of TLVs. The supplied buffer must already be large
* enough. */
void otrl_tlv_serialize(unsigned char *buf, const OtrlTLV *tlv);
/* Return the first TLV with the given type in the chain, or NULL if one
* isn't found. (The tlvs argument isn't const because the return type
* needs to be non-const.) */
OtrlTLV *otrl_tlv_find(OtrlTLV *tlvs, unsigned short type);
#endif
