crypto.h File Reference

WPA Supplicant / wrapper functions for crypto libraries. More...

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Defines
#define	md5_vector_non_fips_allow   md5_vector
Enumerations
enum	crypto_hash_alg {   CRYPTO_HASH_ALG_MD5, CRYPTO_HASH_ALG_SHA1, CRYPTO_HASH_ALG_HMAC_MD5, CRYPTO_HASH_ALG_HMAC_SHA1,   CRYPTO_HASH_ALG_SHA256, CRYPTO_HASH_ALG_HMAC_SHA256 }
enum	crypto_cipher_alg {   CRYPTO_CIPHER_NULL = 0, CRYPTO_CIPHER_ALG_AES, CRYPTO_CIPHER_ALG_3DES, CRYPTO_CIPHER_ALG_DES,   CRYPTO_CIPHER_ALG_RC2, CRYPTO_CIPHER_ALG_RC4 }
Functions
int	md4_vector (size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
	MD4 hash for data vector.
int	md5_vector (size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
	MD5 hash for data vector.
int	sha1_vector (size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
	SHA-1 hash for data vector.
int __must_check	fips186_2_prf (const u8 *seed, size_t seed_len, u8 *x, size_t xlen)
	NIST FIPS Publication 186-2 change notice 1 PRF.
int	sha256_vector (size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
	SHA256 hash for data vector.
void	des_encrypt (const u8 *clear, const u8 *key, u8 *cypher)
	Encrypt one block with DES.
void *	aes_encrypt_init (const u8 *key, size_t len)
	Initialize AES for encryption.
void	aes_encrypt (void *ctx, const u8 *plain, u8 *crypt)
	Encrypt one AES block.
void	aes_encrypt_deinit (void *ctx)
	Deinitialize AES encryption.
void *	aes_decrypt_init (const u8 *key, size_t len)
	Initialize AES for decryption.
void	aes_decrypt (void *ctx, const u8 *crypt, u8 *plain)
	Decrypt one AES block.
void	aes_decrypt_deinit (void *ctx)
	Deinitialize AES decryption.
struct crypto_hash *	crypto_hash_init (enum crypto_hash_alg alg, const u8 *key, size_t key_len)
	Initialize hash/HMAC function.
void	crypto_hash_update (struct crypto_hash *ctx, const u8 *data, size_t len)
	Add data to hash calculation.
int	crypto_hash_finish (struct crypto_hash *ctx, u8 *hash, size_t *len)
	Complete hash calculation.
struct crypto_cipher *	crypto_cipher_init (enum crypto_cipher_alg alg, const u8 *iv, const u8 *key, size_t key_len)
	Initialize block/stream cipher function.
int __must_check	crypto_cipher_encrypt (struct crypto_cipher *ctx, const u8 *plain, u8 *crypt, size_t len)
	Cipher encrypt.
int __must_check	crypto_cipher_decrypt (struct crypto_cipher *ctx, const u8 *crypt, u8 *plain, size_t len)
	Cipher decrypt.
void	crypto_cipher_deinit (struct crypto_cipher *ctx)
	Free cipher context.
struct crypto_public_key *	crypto_public_key_import (const u8 *key, size_t len)
	Import an RSA public key.
struct crypto_private_key *	crypto_private_key_import (const u8 *key, size_t len, const char *passwd)
	Import an RSA private key.
struct crypto_public_key *	crypto_public_key_from_cert (const u8 *buf, size_t len)
	Import an RSA public key from a certificate.
int __must_check	crypto_public_key_encrypt_pkcs1_v15 (struct crypto_public_key *key, const u8 *in, size_t inlen, u8 *out, size_t *outlen)
	Public key encryption (PKCS #1 v1.5)
int __must_check	crypto_private_key_decrypt_pkcs1_v15 (struct crypto_private_key *key, const u8 *in, size_t inlen, u8 *out, size_t *outlen)
	Private key decryption (PKCS #1 v1.5)
int __must_check	crypto_private_key_sign_pkcs1 (struct crypto_private_key *key, const u8 *in, size_t inlen, u8 *out, size_t *outlen)
	Sign with private key (PKCS #1)
void	crypto_public_key_free (struct crypto_public_key *key)
	Free public key.
void	crypto_private_key_free (struct crypto_private_key *key)
	Free private key.
int __must_check	crypto_public_key_decrypt_pkcs1 (struct crypto_public_key *key, const u8 *crypt, size_t crypt_len, u8 *plain, size_t *plain_len)
	Decrypt PKCS #1 signature.
int __must_check	crypto_global_init (void)
	Initialize crypto wrapper.
void	crypto_global_deinit (void)
	Deinitialize crypto wrapper.
int __must_check	crypto_mod_exp (const u8 *base, size_t base_len, const u8 *power, size_t power_len, const u8 *modulus, size_t modulus_len, u8 *result, size_t *result_len)
	Modular exponentiation of large integers.
int	rc4_skip (const u8 *key, size_t keylen, size_t skip, u8 *data, size_t data_len)
	XOR RC4 stream to given data with skip-stream-start.

---

Detailed Description

WPA Supplicant / wrapper functions for crypto libraries.

Copyright

Copyright (c) 2004-2009, Jouni Malinen <j@w1.fi>

This software may be distributed under the terms of the BSD license. See README for more details.

This file defines the cryptographic functions that need to be implemented for wpa_supplicant and hostapd. When TLS is not used, internal implementation of MD5, SHA1, and AES is used and no external libraries are required. When TLS is enabled (e.g., by enabling EAP-TLS or EAP-PEAP), the crypto library used by the TLS implementation is expected to be used for non-TLS needs, too, in order to save space by not implementing these functions twice.

Wrapper code for using each crypto library is in its own file (crypto*.c) and one of these files is build and linked in to provide the functions defined here.

---

Function Documentation

void aes_decrypt	(	void *	ctx,
		const u8 *	crypt,
		u8 *	plain
	)

Decrypt one AES block.

Parameters:

ctx	Context pointer from aes_encrypt_init()
crypt	Encrypted data (16 bytes)
plain	Buffer for the decrypted data (16 bytes)

void aes_decrypt_deinit

(

void *

ctx

)

Deinitialize AES decryption.

Parameters:

ctx	Context pointer from aes_encrypt_init()

void* aes_decrypt_init	(	const u8 *	key,
		size_t	len
	)

Initialize AES for decryption.

Parameters:

key	Decryption key
len	Key length in bytes (usually 16, i.e., 128 bits)

Returns:

Pointer to context data or NULL on failure

void aes_encrypt	(	void *	ctx,
		const u8 *	plain,
		u8 *	crypt
	)

Encrypt one AES block.

Parameters:

ctx	Context pointer from aes_encrypt_init()
plain	Plaintext data to be encrypted (16 bytes)
crypt	Buffer for the encrypted data (16 bytes)

void aes_encrypt_deinit

(

void *

ctx

)

Deinitialize AES encryption.

Parameters:

ctx	Context pointer from aes_encrypt_init()

void* aes_encrypt_init	(	const u8 *	key,
		size_t	len
	)

Initialize AES for encryption.

Parameters:

key	Encryption key
len	Key length in bytes (usually 16, i.e., 128 bits)

Returns:

Pointer to context data or NULL on failure

int __must_check crypto_cipher_decrypt	(	struct crypto_cipher *	ctx,
		const u8 *	crypt,
		u8 *	plain,
		size_t	len
	)

Cipher decrypt.

Parameters:

ctx	Context pointer from crypto_cipher_init()
crypt	Ciphertext to decrypt
plain	Resulting plaintext
len	Length of the cipher text

Returns:

0 on success, -1 on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void crypto_cipher_deinit

(

struct crypto_cipher *

ctx

)

Free cipher context.

Parameters:

ctx	Context pointer from crypto_cipher_init()

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_cipher_encrypt	(	struct crypto_cipher *	ctx,
		const u8 *	plain,
		u8 *	crypt,
		size_t	len
	)

Cipher encrypt.

Parameters:

ctx	Context pointer from crypto_cipher_init()
plain	Plaintext to cipher
crypt	Resulting ciphertext
len	Length of the plaintext

Returns:

0 on success, -1 on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

struct crypto_cipher* crypto_cipher_init	(	enum crypto_cipher_alg	alg,
		const u8 *	iv,
		const u8 *	key,
		size_t	key_len
	)		[read]

Initialize block/stream cipher function.

Parameters:

alg	Cipher algorithm
iv	Initialization vector for block ciphers or NULL for stream ciphers
key	Cipher key
key_len	Length of key in bytes

Returns:

Pointer to cipher context to use with other cipher functions or NULL on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void crypto_global_deinit

(

void

)

Deinitialize crypto wrapper.

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_global_init

(

void

)

Initialize crypto wrapper.

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int crypto_hash_finish	(	struct crypto_hash *	ctx,
		u8 *	hash,
		size_t *	len
	)

Complete hash calculation.

Parameters:

ctx	Context pointer from crypto_hash_init()
hash	Buffer for hash value or NULL if caller is just freeing the hash context
len	Pointer to length of the buffer or NULL if caller is just freeing the hash context; on return, this is set to the actual length of the hash value

Returns:

0 on success, -1 if buffer is too small (len set to needed length), or -2 on other failures (including failed crypto_hash_update() operations)

This function calculates the hash value and frees the context buffer that was used for hash calculation.

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

struct crypto_hash* crypto_hash_init	(	enum crypto_hash_alg	alg,
		const u8 *	key,
		size_t	key_len
	)		[read]

Initialize hash/HMAC function.

Parameters:

alg	Hash algorithm
key	Key for keyed hash (e.g., HMAC) or NULL if not needed
key_len	Length of the key in bytes

Returns:

Pointer to hash context to use with other hash functions or NULL on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void crypto_hash_update	(	struct crypto_hash *	ctx,
		const u8 *	data,
		size_t	len
	)

Add data to hash calculation.

Parameters:

ctx	Context pointer from crypto_hash_init()
data	Data buffer to add
len	Length of the buffer

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_mod_exp	(	const u8 *	base,
		size_t	base_len,
		const u8 *	power,
		size_t	power_len,
		const u8 *	modulus,
		size_t	modulus_len,
		u8 *	result,
		size_t *	result_len
	)

Modular exponentiation of large integers.

Parameters:

base	Base integer (big endian byte array)
base_len	Length of base integer in bytes
power	Power integer (big endian byte array)
power_len	Length of power integer in bytes
modulus	Modulus integer (big endian byte array)
modulus_len	Length of modulus integer in bytes
result	Buffer for the result
result_len	Result length (max buffer size on input, real len on output)

Returns:

0 on success, -1 on failure

This function calculates result = base ^ power mod modulus. modules_len is used as the maximum size of modulus buffer. It is set to the used size on success.

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_private_key_decrypt_pkcs1_v15	(	struct crypto_private_key *	key,
		const u8 *	in,
		size_t	inlen,
		u8 *	out,
		size_t *	outlen
	)

Private key decryption (PKCS #1 v1.5)

Parameters:

key	Private key
in	Encrypted buffer
inlen	Length of encrypted buffer in bytes
out	Output buffer for encrypted data
outlen	Length of output buffer in bytes; set to used length on success

Returns:

0 on success, -1 on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void crypto_private_key_free

(

struct crypto_private_key *

key

)

Free private key.

Parameters:

key	Private key from crypto_private_key_import()

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

struct crypto_private_key* crypto_private_key_import	(	const u8 *	key,
		size_t	len,
		const char *	passwd
	)		[read]

Import an RSA private key.

Parameters:

key	Key buffer (DER encoded RSA private key)
len	Key buffer length in bytes
passwd	Key encryption password or NULL if key is not encrypted

Returns:

Pointer to the private key or NULL on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_private_key_sign_pkcs1	(	struct crypto_private_key *	key,
		const u8 *	in,
		size_t	inlen,
		u8 *	out,
		size_t *	outlen
	)

Sign with private key (PKCS #1)

Parameters:

key	Private key from crypto_private_key_import()
in	Plaintext buffer
inlen	Length of plaintext buffer in bytes
out	Output buffer for encrypted (signed) data
outlen	Length of output buffer in bytes; set to used length on success

Returns:

0 on success, -1 on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

int __must_check crypto_public_key_decrypt_pkcs1	(	struct crypto_public_key *	key,
		const u8 *	crypt,
		size_t	crypt_len,
		u8 *	plain,
		size_t *	plain_len
	)

Decrypt PKCS #1 signature.

Parameters:

key	Public key
crypt	Encrypted signature data (using the private key)
crypt_len	Encrypted signature data length
plain	Buffer for plaintext (at least crypt_len bytes)
plain_len	Plaintext length (max buffer size on input, real len on output);

Returns:

0 on success, -1 on failure

int __must_check crypto_public_key_encrypt_pkcs1_v15	(	struct crypto_public_key *	key,
		const u8 *	in,
		size_t	inlen,
		u8 *	out,
		size_t *	outlen
	)

Public key encryption (PKCS #1 v1.5)

Parameters:

key	Public key
in	Plaintext buffer
inlen	Length of plaintext buffer in bytes
out	Output buffer for encrypted data
outlen	Length of output buffer in bytes; set to used length on success

Returns:

0 on success, -1 on failure

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void crypto_public_key_free

(

struct crypto_public_key *

key

)

Free public key.

Parameters:

key	Public key

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

struct crypto_public_key* crypto_public_key_from_cert	(	const u8 *	buf,
		size_t	len
	)		[read]

Import an RSA public key from a certificate.

Parameters:

buf	DER encoded X.509 certificate
len	Certificate buffer length in bytes

Returns:

Pointer to public key or NULL on failure

This function can just return NULL if the crypto library does not support X.509 parsing. In that case, internal code will be used to parse the certificate and public key is imported using crypto_public_key_import().

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

struct crypto_public_key* crypto_public_key_import	(	const u8 *	key,
		size_t	len
	)		[read]

Import an RSA public key.

Parameters:

key	Key buffer (DER encoded RSA public key)
len	Key buffer length in bytes

Returns:

Pointer to the public key or NULL on failure

This function can just return NULL if the crypto library supports X.509 parsing. In that case, crypto_public_key_from_cert() is used to import the public key from a certificate.

This function is only used with internal TLSv1 implementation (CONFIG_TLS=internal). If that is not used, the crypto wrapper does not need to implement this.

void des_encrypt	(	const u8 *	clear,
		const u8 *	key,
		u8 *	cypher
	)

Encrypt one block with DES.

Parameters:

clear	8 octets (in)
key	7 octets (in) (no parity bits included)
cypher	8 octets (out)

int __must_check fips186_2_prf	(	const u8 *	seed,
		size_t	seed_len,
		u8 *	x,
		size_t	xlen
	)

NIST FIPS Publication 186-2 change notice 1 PRF.

Parameters:

seed	Seed/key for the PRF
seed_len	Seed length in bytes
x	Buffer for PRF output
xlen	Output length in bytes

Returns:

0 on success, -1 on failure

This function implements random number generation specified in NIST FIPS Publication 186-2 for EAP-SIM. This PRF uses a function that is similar to SHA-1, but has different message padding.

int md4_vector	(	size_t	num_elem,
		const u8 *	addr[],
		const size_t *	len,
		u8 *	mac
	)

MD4 hash for data vector.

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 on failure

int md5_vector	(	size_t	num_elem,
		const u8 *	addr[],
		const size_t *	len,
		u8 *	mac
	)

MD5 hash for data vector.

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 on failure

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 of failure

int rc4_skip	(	const u8 *	key,
		size_t	keylen,
		size_t	skip,
		u8 *	data,
		size_t	data_len
	)

XOR RC4 stream to given data with skip-stream-start.

Parameters:

key	RC4 key
keylen	RC4 key length
skip	number of bytes to skip from the beginning of the RC4 stream
data	data to be XOR'ed with RC4 stream
data_len	buf length

Returns:

0 on success, -1 on failure

Generate RC4 pseudo random stream for the given key, skip beginning of the stream, and XOR the end result with the data buffer to perform RC4 encryption/decryption.

int sha1_vector	(	size_t	num_elem,
		const u8 *	addr[],
		const size_t *	len,
		u8 *	mac
	)

SHA-1 hash for data vector.

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 on failure

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 of failure

int sha256_vector	(	size_t	num_elem,
		const u8 *	addr[],
		const size_t *	len,
		u8 *	mac
	)

SHA256 hash for data vector.

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 on failure

Parameters:

num_elem	Number of elements in the data vector
addr	Pointers to the data areas
len	Lengths of the data blocks
mac	Buffer for the hash

Returns:

0 on success, -1 of failure