TLS helper functions

Macros
#define	MBEDTLS_ECDSA_DER_MAX_SIG_LEN(bits)
	Maximum size of a DER-encoded ECDSA signature for a given curve bit size. More...
#define	MBEDTLS_ECDSA_DER_MAX_LEN   MBEDTLS_ECDSA_DER_MAX_SIG_LEN(PSA_VENDOR_ECC_MAX_CURVE_BITS)

Functions
static psa_algorithm_t	mbedtls_md_psa_alg_from_type (mbedtls_md_type_t md_type)
	This function returns the PSA algorithm identifier associated with the given digest type. More...
static mbedtls_md_type_t	mbedtls_md_type_from_psa_alg (psa_algorithm_t psa_alg)
	This function returns the given digest type associated with the PSA algorithm identifier. More...
int	mbedtls_ecdsa_raw_to_der (size_t bits, const unsigned char *raw, size_t raw_len, unsigned char *der, size_t der_size, size_t *der_len)
int	mbedtls_ecdsa_der_to_raw (size_t bits, const unsigned char *der, size_t der_len, unsigned char *raw, size_t raw_size, size_t *raw_len)

Detailed Description

Macro Definition Documentation

#define MBEDTLS_ECDSA_DER_MAX_LEN   MBEDTLS_ECDSA_DER_MAX_SIG_LEN(PSA_VENDOR_ECC_MAX_CURVE_BITS)

The maximal size of a DER-encoded ECDSA signature in Bytes.

Definition at line 136 of file psa_util.h.

#define MBEDTLS_ECDSA_DER_MAX_SIG_LEN

(

bits

)

Value:

(/*T,L of SEQUENCE*/ ((bits) >= 61 * 8 ? 3 : 2) +              \
     /*T,L of r,s*/ 2 * (((bits) >= 127 * 8 ? 3 : 2) +     \
                         /*V of r,s*/ ((bits) + 8) / 8))

Maximum size of a DER-encoded ECDSA signature for a given curve bit size.

Parameters

bits	Curve size in bits.

Returns

Maximum signature size in bytes.

Note

This macro returns a compile-time constant if its argument is one. It may evaluate its argument multiple times.

Definition at line 130 of file psa_util.h.

Function Documentation

int mbedtls_ecdsa_der_to_raw	(	size_t	bits,
		const unsigned char *	der,
		size_t	der_len,
		unsigned char *	raw,
		size_t	raw_size,
		size_t *	raw_len
	)

Convert an ECDSA signature from DER ASN.1 format to raw format.

Parameters

	bits	Size of each coordinate in bits.
	der	Buffer that contains the signature in DER format.
	der_len	Size of der in bytes.
[out]	raw	Buffer that will be filled with the converted raw signature. It can overlap with der buffer.
	raw_size	Size of raw in bytes. Must be at least 2 * PSA_BITS_TO_BYTES(bits) bytes.
[out]	raw_len	On success it is updated with the amount of valid data (in bytes) written to raw. It's undefined in case of failure.

Returns

0 if successful.

PSA_ERROR_BUFFER_TOO_SMALL if raw_size is too small or if bits is larger than the largest supported curve.

MBEDTLS_ERR_ASN1_INVALID_DATA if the data in der is inconsistent with bits.

An MBEDTLS_ERR_ASN1_xxx error code if der is malformed.

int mbedtls_ecdsa_raw_to_der	(	size_t	bits,
		const unsigned char *	raw,
		size_t	raw_len,
		unsigned char *	der,
		size_t	der_size,
		size_t *	der_len
	)

Convert an ECDSA signature from raw format to DER ASN.1 format.

Parameters

	bits	Size of each coordinate in bits.
	raw	Buffer that contains the signature in raw format.
	raw_len	Length of raw in bytes. This must be PSA_BITS_TO_BYTES(bits) bytes.
[out]	der	Buffer that will be filled with the converted DER output. It can overlap with raw buffer.
	der_size	Size of der in bytes. It is enough if der_size is at least the size of the actual output. (The size of the output can vary depending on the presence of leading zeros in the data.) You can use MBEDTLS_ECDSA_DER_MAX_SIG_LEN(bits) to determine a size that is large enough for all signatures for a given value of bits.
[out]	der_len	On success it contains the amount of valid data (in bytes) written to der. It's undefined in case of failure.

Note

The behavior is undefined if der is null, even if der_size is 0.

Returns

0 if successful.

PSA_ERROR_BUFFER_TOO_SMALL if der_size is too small or if bits is larger than the largest supported curve.

MBEDTLS_ERR_ASN1_INVALID_DATA if one of the numbers in the signature is 0.

static psa_algorithm_t mbedtls_md_psa_alg_from_type ( mbedtls_md_type_t  md_type )

inlinestatic

This function returns the PSA algorithm identifier associated with the given digest type.

Parameters

md_type

The type of digest to search for. Must not be NONE.

Warning

If md_type is MBEDTLS_MD_NONE, this function will not return PSA_ALG_NONE, but an invalid algorithm.

This function does not check if the algorithm is supported, it always returns the corresponding identifier.

Returns

The PSA algorithm identifier associated with md_type, regardless of whether it is supported or not.

Definition at line 87 of file psa_util.h.

References PSA_ALG_CATEGORY_HASH.

static mbedtls_md_type_t mbedtls_md_type_from_psa_alg ( psa_algorithm_t  psa_alg )

inlinestatic

This function returns the given digest type associated with the PSA algorithm identifier.

Parameters

psa_alg

The PSA algorithm identifier to search for.

Warning

This function does not check if the algorithm is supported, it always returns the corresponding identifier.

Returns

The MD type associated with psa_alg, regardless of whether it is supported or not.

Definition at line 104 of file psa_util.h.

References PSA_ALG_HASH_MASK.