1/* 2 * EAP server/peer: EAP-pwd shared definitions 3 * Copyright (c) 2009, Dan Harkins <dharkins@lounge.org> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the BSD license. 7 * 8 * Alternatively, this software may be distributed under the terms of the 9 * GNU General Public License version 2 as published by the Free Software 10 * Foundation. 11 * 12 * See README and COPYING for more details. 13 */ 14 15#ifndef EAP_PWD_COMMON_H 16#define EAP_PWD_COMMON_H 17 18#include <openssl/bn.h> 19#include <openssl/sha.h> 20#include <openssl/ec.h> 21#include <openssl/evp.h> 22#include <openssl/hmac.h> 23 24/* 25 * definition of a finite cyclic group 26 * TODO: support one based on a prime field 27 */ 28typedef struct group_definition_ { 29 u16 group_num; 30 EC_GROUP *group; 31 EC_POINT *pwe; 32 BIGNUM *order; 33 BIGNUM *prime; 34} EAP_PWD_group; 35 36/* 37 * EAP-pwd header, included on all payloads 38 */ 39struct eap_pwd_hdr { 40 u8 l_bit:1; 41 u8 m_bit:1; 42 u8 exch:6; 43 u8 total_length[0]; /* included when l_bit is set */ 44} STRUCT_PACKED; 45 46#define EAP_PWD_OPCODE_ID_EXCH 1 47#define EAP_PWD_OPCODE_COMMIT_EXCH 2 48#define EAP_PWD_OPCODE_CONFIRM_EXCH 3 49#define EAP_PWD_GET_LENGTH_BIT(x) ((x)->lm_exch & 0x80) 50#define EAP_PWD_SET_LENGTH_BIT(x) ((x)->lm_exch |= 0x80) 51#define EAP_PWD_GET_MORE_BIT(x) ((x)->lm_exch & 0x40) 52#define EAP_PWD_SET_MORE_BIT(x) ((x)->lm_exch |= 0x40) 53#define EAP_PWD_GET_EXCHANGE(x) ((x)->lm_exch & 0x3f) 54#define EAP_PWD_SET_EXCHANGE(x,y) ((x)->lm_exch |= (y)) 55 56/* EAP-pwd-ID payload */ 57struct eap_pwd_id { 58 be16 group_num; 59 u8 random_function; 60#define EAP_PWD_DEFAULT_RAND_FUNC 1 61 u8 prf; 62#define EAP_PWD_DEFAULT_PRF 1 63 u8 token[4]; 64 u8 prep; 65#define EAP_PWD_PREP_NONE 0 66#define EAP_PWD_PREP_MS 1 67 u8 identity[0]; /* length inferred from payload */ 68} STRUCT_PACKED; 69 70/* common routines */ 71int compute_password_element(EAP_PWD_group *, u16, u8 *, int, u8 *, int, u8 *, 72 int, u8 *); 73int compute_keys(EAP_PWD_group *, BN_CTX *, BIGNUM *, BIGNUM *, BIGNUM *, 74 u8 *, u8 *, u32 *, u8 *, u8 *); 75void H_Init(HMAC_CTX *); 76void H_Update(HMAC_CTX *, const u8 *, int); 77void H_Final(HMAC_CTX *, u8 *); 78 79#endif /* EAP_PWD_COMMON_H */ 80