src/eap_common/eap_pwd_common.h

   1 /*
   2  * EAP server/peer: EAP-pwd shared definitions
   3  * Copyright (c) 2009, Dan Harkins <dharkins@lounge.org>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #ifndef EAP_PWD_COMMON_H
  10 #define EAP_PWD_COMMON_H
  11
  12 #include <openssl/bn.h>
  13 #include <openssl/ec.h>
  14 #include <openssl/evp.h>
  15
  16 /*
  17  * definition of a finite cyclic group
  18  * TODO: support one based on a prime field
  19  */
  20 typedef struct group_definition_ {
  21         u16 group_num;
  22         EC_GROUP *group;
  23         EC_POINT *pwe;
  24         BIGNUM *order;
  25         BIGNUM *prime;
  26 } EAP_PWD_group;
  27
  28 /*
  29  * EAP-pwd header, included on all payloads
  30  * L(1 bit) | M(1 bit) | exch(6 bits) | total_length(if L is set)
  31  */
  32 #define EAP_PWD_HDR_SIZE                1
  33
  34 #define EAP_PWD_OPCODE_ID_EXCH          1
  35 #define EAP_PWD_OPCODE_COMMIT_EXCH      2
  36 #define EAP_PWD_OPCODE_CONFIRM_EXCH     3
  37 #define EAP_PWD_GET_LENGTH_BIT(x)       ((x) & 0x80)
  38 #define EAP_PWD_SET_LENGTH_BIT(x)       ((x) |= 0x80)
  39 #define EAP_PWD_GET_MORE_BIT(x)         ((x) & 0x40)
  40 #define EAP_PWD_SET_MORE_BIT(x)         ((x) |= 0x40)
  41 #define EAP_PWD_GET_EXCHANGE(x)         ((x) & 0x3f)
  42 #define EAP_PWD_SET_EXCHANGE(x,y)       ((x) |= (y))
  43
  44 /* EAP-pwd-ID payload */
  45 struct eap_pwd_id {
  46         be16 group_num;
  47         u8 random_function;
  48 #define EAP_PWD_DEFAULT_RAND_FUNC       1
  49         u8 prf;
  50 #define EAP_PWD_DEFAULT_PRF             1
  51         u8 token[4];
  52         u8 prep;
  53 #define EAP_PWD_PREP_NONE               0
  54 #define EAP_PWD_PREP_MS                 1
  55         u8 identity[0];     /* length inferred from payload */
  56 } STRUCT_PACKED;
  57
  58 /* common routines */
  59 int compute_password_element(EAP_PWD_group *, u16, u8 *, int, u8 *, int, u8 *,
  60                              int, u8 *);
  61 int compute_keys(EAP_PWD_group *, BN_CTX *, BIGNUM *, BIGNUM *, BIGNUM *,
  62                  u8 *, u8 *, u32 *, u8 *, u8 *);
  63 struct crypto_hash * eap_pwd_h_init(void);
  64 void eap_pwd_h_update(struct crypto_hash *hash, const u8 *data, size_t len);
  65 void eap_pwd_h_final(struct crypto_hash *hash, u8 *digest);
  66
  67 #endif  /* EAP_PWD_COMMON_H */