WiiFlow_Lite/source/libwolfssl/wolfcrypt/srp.h

312 lines
11 KiB
C

/* srp.h
*
* Copyright (C) 2006-2021 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* wolfSSL 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 2 of the License, or
* (at your option) any later version.
*
* wolfSSL 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
*/
/*!
\file wolfssl/wolfcrypt/srp.h
*/
#ifdef WOLFCRYPT_HAVE_SRP
#ifndef WOLFCRYPT_SRP_H
#define WOLFCRYPT_SRP_H
#include <libwolfssl/wolfcrypt/types.h>
#include <libwolfssl/wolfcrypt/sha.h>
#include <libwolfssl/wolfcrypt/sha256.h>
#include <libwolfssl/wolfcrypt/sha512.h>
#include <libwolfssl/wolfcrypt/integer.h>
#ifdef __cplusplus
extern "C" {
#endif
/* Select the largest available hash for the buffer size. */
#if defined(WOLFSSL_SHA512)
#define SRP_MAX_DIGEST_SIZE WC_SHA512_DIGEST_SIZE
#elif defined(WOLFSSL_SHA384)
#define SRP_MAX_DIGEST_SIZE WC_SHA384_DIGEST_SIZE
#elif !defined(NO_SHA256)
#define SRP_MAX_DIGEST_SIZE WC_SHA256_DIGEST_SIZE
#elif !defined(NO_SHA)
#define SRP_MAX_DIGEST_SIZE WC_SHA_DIGEST_SIZE
#else
#error "You have to have some kind of SHA hash if you want to use SRP."
#endif
/* Set the minimum number of bits acceptable in an SRP modulus */
#define SRP_MODULUS_MIN_BITS 512
/* Set the minimum number of bits acceptable for private keys (RFC 5054) */
#define SRP_PRIVATE_KEY_MIN_BITS 256
/* salt size for SRP password */
#define SRP_SALT_SIZE 16
/**
* SRP side, client or server.
*/
typedef enum {
SRP_CLIENT_SIDE = 0,
SRP_SERVER_SIDE = 1,
} SrpSide;
/**
* SRP hash type, SHA[1|256|384|512].
*/
typedef enum {
SRP_TYPE_SHA = 1,
SRP_TYPE_SHA256 = 2,
SRP_TYPE_SHA384 = 3,
SRP_TYPE_SHA512 = 4,
} SrpType;
/**
* SRP hash struct.
*/
typedef struct {
byte type;
union {
#ifndef NO_SHA
wc_Sha sha;
#endif
#ifndef NO_SHA256
wc_Sha256 sha256;
#endif
#ifdef WOLFSSL_SHA384
wc_Sha384 sha384;
#endif
#ifdef WOLFSSL_SHA512
wc_Sha512 sha512;
#endif
} data;
} SrpHash;
typedef struct Srp {
SrpSide side; /**< Client or Server, @see SrpSide. */
SrpType type; /**< Hash type, @see SrpType. */
byte* user; /**< Username, login. */
word32 userSz; /**< Username length. */
byte* salt; /**< Small salt. */
word32 saltSz; /**< Salt length. */
mp_int N; /**< Modulus. N = 2q+1, [q, N] are primes.*/
mp_int g; /**< Generator. A generator modulo N. */
byte k[SRP_MAX_DIGEST_SIZE]; /**< Multiplier parameter. k = H(N, g) */
mp_int auth; /**< Client: x = H(salt + H(user:pswd)) */
/**< Server: v = g ^ x % N */
mp_int priv; /**< Private ephemeral value. */
SrpHash client_proof; /**< Client proof. Sent to the Server. */
SrpHash server_proof; /**< Server proof. Sent to the Client. */
byte* key; /**< Session key. */
word32 keySz; /**< Session key length. */
int (*keyGenFunc_cb) (struct Srp* srp, byte* secret, word32 size);
/**< Function responsible for generating the session key. */
/**< It MUST use XMALLOC with type DYNAMIC_TYPE_SRP to allocate the */
/**< key buffer for this structure and set keySz to the buffer size. */
/**< The default function used by this implementation is a modified */
/**< version of t_mgf1 that uses the proper hash function according */
/**< to srp->type. */
void* heap; /**< heap hint pointer */
} Srp;
/**
* Initializes the Srp struct for usage.
*
* @param[out] srp the Srp structure to be initialized.
* @param[in] type the hash type to be used.
* @param[in] side the side of the communication.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpInit(Srp* srp, SrpType type, SrpSide side);
/**
* Releases the Srp struct resources after usage.
*
* @param[in,out] srp the Srp structure to be terminated.
*/
WOLFSSL_API void wc_SrpTerm(Srp* srp);
/**
* Sets the username.
*
* This function MUST be called after wc_SrpInit.
*
* @param[in,out] srp the Srp structure.
* @param[in] username the buffer containing the username.
* @param[in] size the username size in bytes
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpSetUsername(Srp* srp, const byte* username, word32 size);
/**
* Sets the srp parameters based on the username.
*
* This function MUST be called after wc_SrpSetUsername.
*
* @param[in,out] srp the Srp structure.
* @param[in] N the Modulus. N = 2q+1, [q, N] are primes.
* @param[in] nSz the N size in bytes.
* @param[in] g the Generator modulo N.
* @param[in] gSz the g size in bytes
* @param[in] salt a small random salt. Specific for each username.
* @param[in] saltSz the salt size in bytes
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpSetParams(Srp* srp, const byte* N, word32 nSz,
const byte* g, word32 gSz,
const byte* salt, word32 saltSz);
/**
* Sets the password.
*
* Setting the password does not persists the clear password data in the
* srp structure. The client calculates x = H(salt + H(user:pswd)) and stores
* it in the auth field.
*
* This function MUST be called after wc_SrpSetParams and is CLIENT SIDE ONLY.
*
* @param[in,out] srp the Srp structure.
* @param[in] password the buffer containing the password.
* @param[in] size the password size in bytes.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpSetPassword(Srp* srp, const byte* password, word32 size);
/**
* Sets the verifier.
*
* This function MUST be called after wc_SrpSetParams and is SERVER SIDE ONLY.
*
* @param[in,out] srp the Srp structure.
* @param[in] verifier the buffer containing the verifier.
* @param[in] size the verifier size in bytes.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpSetVerifier(Srp* srp, const byte* verifier, word32 size);
/**
* Gets the verifier.
*
* The client calculates the verifier with v = g ^ x % N.
* This function MAY be called after wc_SrpSetPassword and is CLIENT SIDE ONLY.
*
* @param[in,out] srp the Srp structure.
* @param[out] verifier the buffer to write the verifier.
* @param[in,out] size the buffer size in bytes. Will be updated with the
* verifier size.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpGetVerifier(Srp* srp, byte* verifier, word32* size);
/**
* Sets the private ephemeral value.
*
* The private ephemeral value is known as:
* a at the client side. a = random()
* b at the server side. b = random()
* This function is handy for unit test cases or if the developer wants to use
* an external random source to set the ephemeral value.
* This function MAY be called before wc_SrpGetPublic.
*
* @param[in,out] srp the Srp structure.
* @param[in] priv the ephemeral value.
* @param[in] size the private size in bytes.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpSetPrivate(Srp* srp, const byte* priv, word32 size);
/**
* Gets the public ephemeral value.
*
* The public ephemeral value is known as:
* A at the client side. A = g ^ a % N
* B at the server side. B = (k * v + (g ^ b % N)) % N
* This function MUST be called after wc_SrpSetPassword or wc_SrpSetVerifier.
*
* @param[in,out] srp the Srp structure.
* @param[out] pub the buffer to write the public ephemeral value.
* @param[in,out] size the the buffer size in bytes. Will be updated with
* the ephemeral value size.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpGetPublic(Srp* srp, byte* pub, word32* size);
/**
* Computes the session key.
*
* The key can be accessed at srp->key after success.
*
* @param[in,out] srp the Srp structure.
* @param[in] clientPubKey the client's public ephemeral value.
* @param[in] clientPubKeySz the client's public ephemeral value size.
* @param[in] serverPubKey the server's public ephemeral value.
* @param[in] serverPubKeySz the server's public ephemeral value size.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpComputeKey(Srp* srp,
byte* clientPubKey, word32 clientPubKeySz,
byte* serverPubKey, word32 serverPubKeySz);
/**
* Gets the proof.
*
* This function MUST be called after wc_SrpComputeKey.
*
* @param[in,out] srp the Srp structure.
* @param[out] proof the buffer to write the proof.
* @param[in,out] size the buffer size in bytes. Will be updated with the
* proof size.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpGetProof(Srp* srp, byte* proof, word32* size);
/**
* Verifies the peers proof.
*
* This function MUST be called before wc_SrpGetSessionKey.
*
* @param[in,out] srp the Srp structure.
* @param[in] proof the peers proof.
* @param[in] size the proof size in bytes.
*
* @return 0 on success, {@literal <} 0 on error. @see error-crypt.h
*/
WOLFSSL_API int wc_SrpVerifyPeersProof(Srp* srp, byte* proof, word32 size);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* WOLFCRYPT_SRP_H */
#endif /* WOLFCRYPT_HAVE_SRP */