Revision control
Copy as Markdown
Other Tools
/*
* 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 __SM_H__
#define __SM_H__
#include <gcrypt.h>
#define SM_HASH_ALGORITHM GCRY_MD_SHA256
#define SM_DIGEST_SIZE 32
typedef enum {
OTRL_SMP_EXPECT1,
OTRL_SMP_EXPECT2,
OTRL_SMP_EXPECT3,
OTRL_SMP_EXPECT4,
OTRL_SMP_EXPECT5
} NextExpectedSMP;
typedef enum {
OTRL_SMP_PROG_OK = 0, /* All is going fine so far */
OTRL_SMP_PROG_CHEATED = -2, /* Some verification failed */
OTRL_SMP_PROG_FAILED = -1, /* The secrets didn't match */
OTRL_SMP_PROG_SUCCEEDED = 1 /* The SMP completed successfully */
} OtrlSMProgState;
typedef struct {
gcry_mpi_t secret, x2, x3, g1, g2, g3, g3o, p, q, pab, qab;
NextExpectedSMP nextExpected;
int received_question; /* 1 if we received a question in an SMP1Q TLV */
OtrlSMProgState sm_prog_state;
} OtrlSMState;
typedef OtrlSMState OtrlSMAliceState;
typedef OtrlSMState OtrlSMBobState;
/*
* Call this once, at plugin load time. It sets up the modulus and
* generator MPIs.
*/
void otrl_sm_init(void);
/*
* Initialize the fields of a SM state.
*/
void otrl_sm_state_new(OtrlSMState *smst);
/*
* Initialize the fields of a SM state. Called the first time that
* a user begins an SMP session.
*/
void otrl_sm_state_init(OtrlSMState *smst);
/*
* Deallocate the contents of a OtrlSMState (but not the OtrlSMState
* itself)
*/
void otrl_sm_state_free(OtrlSMState *smst);
gcry_error_t otrl_sm_step1(OtrlSMAliceState *astate, const unsigned char* secret, int secretlen, unsigned char** output, int* outputlen);
gcry_error_t otrl_sm_step2a(OtrlSMBobState *bstate, const unsigned char* input, const int inputlen, int received_question);
gcry_error_t otrl_sm_step2b(OtrlSMBobState *bstate, const unsigned char* secret, int secretlen, unsigned char **output, int* outputlen);
gcry_error_t otrl_sm_step3(OtrlSMAliceState *astate, const unsigned char* input, const int inputlen, unsigned char **output, int* outputlen);
gcry_error_t otrl_sm_step4(OtrlSMBobState *bstate, const unsigned char* input, const int inputlen, unsigned char **output, int* outputlen);
gcry_error_t otrl_sm_step5(OtrlSMAliceState *astate, const unsigned char* input, const int inputlen);
#endif