pk.h File Reference

Public Key abstraction layer. More...

#include "mbedtls/config.h"
#include "mbedtls/md.h"

Go to the source code of this file.

Data Structures
struct	mbedtls_pk_rsassa_pss_options
	Options for RSASSA-PSS signature verification. More...
struct	mbedtls_pk_debug_item
	Item to send to the debug module. More...
struct	mbedtls_pk_context
	Public key container. More...

Macros
#define	MBEDTLS_ERR_PK_ALLOC_FAILED   -0x3F80
	Memory allocation failed. More...
#define	MBEDTLS_ERR_PK_TYPE_MISMATCH   -0x3F00
	Type mismatch, eg attempt to encrypt with an ECDSA key. More...
#define	MBEDTLS_ERR_PK_BAD_INPUT_DATA   -0x3E80
	Bad input parameters to function. More...
#define	MBEDTLS_ERR_PK_FILE_IO_ERROR   -0x3E00
	Read/write of file failed. More...
#define	MBEDTLS_ERR_PK_KEY_INVALID_VERSION   -0x3D80
	Unsupported key version. More...
#define	MBEDTLS_ERR_PK_KEY_INVALID_FORMAT   -0x3D00
	Invalid key tag or value. More...
#define	MBEDTLS_ERR_PK_UNKNOWN_PK_ALG   -0x3C80
	Key algorithm is unsupported (only RSA and EC are supported). More...
#define	MBEDTLS_ERR_PK_PASSWORD_REQUIRED   -0x3C00
	Private key password can't be empty. More...
#define	MBEDTLS_ERR_PK_PASSWORD_MISMATCH   -0x3B80
	Given private key password does not allow for correct decryption. More...
#define	MBEDTLS_ERR_PK_INVALID_PUBKEY   -0x3B00
	The pubkey tag or value is invalid (only RSA and EC are supported). More...
#define	MBEDTLS_ERR_PK_INVALID_ALG   -0x3A80
	The algorithm tag or value is invalid. More...
#define	MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE   -0x3A00
	Elliptic curve is unsupported (only NIST curves are supported). More...
#define	MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE   -0x3980
	Unavailable feature, e.g. More...
#define	MBEDTLS_ERR_PK_SIG_LEN_MISMATCH   -0x3900
	The buffer contains a valid signature followed by more data. More...
#define	MBEDTLS_ERR_PK_HW_ACCEL_FAILED   -0x3880
	PK hardware accelerator failed. More...
#define	MBEDTLS_PK_SIGNATURE_MAX_SIZE   0
	Maximum size of a signature made by mbedtls_pk_sign(). More...
#define	MBEDTLS_PK_DEBUG_MAX_ITEMS   3
	Maximum number of item send for debugging, plus 1. More...

Typedefs
typedef struct mbedtls_pk_rsassa_pss_options	mbedtls_pk_rsassa_pss_options
	Options for RSASSA-PSS signature verification. More...
typedef struct mbedtls_pk_debug_item	mbedtls_pk_debug_item
	Item to send to the debug module. More...
typedef struct mbedtls_pk_info_t	mbedtls_pk_info_t
	Public key information and operations. More...
typedef struct mbedtls_pk_context	mbedtls_pk_context
	Public key container. More...

Enumerations
enum	mbedtls_pk_type_t {   MBEDTLS_PK_NONE =0 , MBEDTLS_PK_RSA , MBEDTLS_PK_ECKEY , MBEDTLS_PK_ECKEY_DH ,   MBEDTLS_PK_ECDSA , MBEDTLS_PK_RSA_ALT , MBEDTLS_PK_RSASSA_PSS , MBEDTLS_PK_OPAQUE }
	Public key types. More...
enum	mbedtls_pk_debug_type
	Types for interfacing with the debug module. More...

Functions
const mbedtls_pk_info_t *	mbedtls_pk_info_from_type (mbedtls_pk_type_t pk_type)
	Return information associated with the given PK type. More...
void	mbedtls_pk_init (mbedtls_pk_context *ctx)
	Initialize a mbedtls_pk_context (as NONE). More...
void	mbedtls_pk_free (mbedtls_pk_context *ctx)
	Free the components of a mbedtls_pk_context. More...
int	mbedtls_pk_setup (mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info)
	Initialize a PK context with the information given and allocates the type-specific PK subcontext. More...
size_t	mbedtls_pk_get_bitlen (const mbedtls_pk_context *ctx)
	Get the size in bits of the underlying key. More...
int	mbedtls_pk_can_do (const mbedtls_pk_context *ctx, mbedtls_pk_type_t type)
	Tell if a context can do the operation given by type. More...
int	mbedtls_pk_verify (mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, const unsigned char *hash, size_t hash_len, const unsigned char *sig, size_t sig_len)
	Verify signature (including padding if relevant). More...
int	mbedtls_pk_verify_restartable (mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, const unsigned char *hash, size_t hash_len, const unsigned char *sig, size_t sig_len, mbedtls_pk_restart_ctx *rs_ctx)
	Restartable version of mbedtls_pk_verify() More...
int	mbedtls_pk_verify_ext (mbedtls_pk_type_t type, const void *options, mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, const unsigned char *hash, size_t hash_len, const unsigned char *sig, size_t sig_len)
	Verify signature, with options. More...
int	mbedtls_pk_sign (mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, const unsigned char *hash, size_t hash_len, unsigned char *sig, size_t *sig_len, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
	Make signature, including padding if relevant. More...
int	mbedtls_pk_sign_restartable (mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, const unsigned char *hash, size_t hash_len, unsigned char *sig, size_t *sig_len, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng, mbedtls_pk_restart_ctx *rs_ctx)
	Restartable version of mbedtls_pk_sign() More...
int	mbedtls_pk_decrypt (mbedtls_pk_context *ctx, const unsigned char *input, size_t ilen, unsigned char *output, size_t *olen, size_t osize, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
	Decrypt message (including padding if relevant). More...
int	mbedtls_pk_encrypt (mbedtls_pk_context *ctx, const unsigned char *input, size_t ilen, unsigned char *output, size_t *olen, size_t osize, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)
	Encrypt message (including padding if relevant). More...
int	mbedtls_pk_check_pair (const mbedtls_pk_context *pub, const mbedtls_pk_context *prv)
	Check if a public-private pair of keys matches. More...
int	mbedtls_pk_debug (const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items)
	Export debug information. More...
const char *	mbedtls_pk_get_name (const mbedtls_pk_context *ctx)
	Access the type name. More...
mbedtls_pk_type_t	mbedtls_pk_get_type (const mbedtls_pk_context *ctx)
	Get the key type. More...

Detailed Description

Public Key abstraction layer.

Definition in file pk.h.

Macro Definition Documentation

MBEDTLS_ERR_PK_ALLOC_FAILED

#define MBEDTLS_ERR_PK_ALLOC_FAILED   -0x3F80

Memory allocation failed.

Definition at line 55 of file pk.h.

MBEDTLS_ERR_PK_TYPE_MISMATCH

#define MBEDTLS_ERR_PK_TYPE_MISMATCH   -0x3F00

Type mismatch, eg attempt to encrypt with an ECDSA key.

Definition at line 56 of file pk.h.

MBEDTLS_ERR_PK_BAD_INPUT_DATA

#define MBEDTLS_ERR_PK_BAD_INPUT_DATA   -0x3E80

Bad input parameters to function.

Definition at line 57 of file pk.h.

MBEDTLS_ERR_PK_FILE_IO_ERROR

#define MBEDTLS_ERR_PK_FILE_IO_ERROR   -0x3E00

Read/write of file failed.

Definition at line 58 of file pk.h.

MBEDTLS_ERR_PK_KEY_INVALID_VERSION

#define MBEDTLS_ERR_PK_KEY_INVALID_VERSION   -0x3D80

Unsupported key version.

Definition at line 59 of file pk.h.

MBEDTLS_ERR_PK_KEY_INVALID_FORMAT

#define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT   -0x3D00

Invalid key tag or value.

Definition at line 60 of file pk.h.

MBEDTLS_ERR_PK_UNKNOWN_PK_ALG

#define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG   -0x3C80

Key algorithm is unsupported (only RSA and EC are supported).

Definition at line 61 of file pk.h.

MBEDTLS_ERR_PK_PASSWORD_REQUIRED

#define MBEDTLS_ERR_PK_PASSWORD_REQUIRED   -0x3C00

Private key password can't be empty.

Definition at line 62 of file pk.h.

MBEDTLS_ERR_PK_PASSWORD_MISMATCH

#define MBEDTLS_ERR_PK_PASSWORD_MISMATCH   -0x3B80

Given private key password does not allow for correct decryption.

Definition at line 63 of file pk.h.

MBEDTLS_ERR_PK_INVALID_PUBKEY

#define MBEDTLS_ERR_PK_INVALID_PUBKEY   -0x3B00

The pubkey tag or value is invalid (only RSA and EC are supported).

Definition at line 64 of file pk.h.

MBEDTLS_ERR_PK_INVALID_ALG

#define MBEDTLS_ERR_PK_INVALID_ALG   -0x3A80

The algorithm tag or value is invalid.

Definition at line 65 of file pk.h.

MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE

#define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE   -0x3A00

Elliptic curve is unsupported (only NIST curves are supported).

Definition at line 66 of file pk.h.

MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE

#define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE   -0x3980

Unavailable feature, e.g.

RSA disabled for RSA key.

Definition at line 67 of file pk.h.

MBEDTLS_ERR_PK_SIG_LEN_MISMATCH

#define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH   -0x3900

The buffer contains a valid signature followed by more data.

Definition at line 68 of file pk.h.

MBEDTLS_ERR_PK_HW_ACCEL_FAILED

#define MBEDTLS_ERR_PK_HW_ACCEL_FAILED   -0x3880

PK hardware accelerator failed.

Definition at line 71 of file pk.h.

MBEDTLS_PK_SIGNATURE_MAX_SIZE

#define MBEDTLS_PK_SIGNATURE_MAX_SIZE   0

Maximum size of a signature made by mbedtls_pk_sign().

Definition at line 114 of file pk.h.

MBEDTLS_PK_DEBUG_MAX_ITEMS

#define MBEDTLS_PK_DEBUG_MAX_ITEMS   3

Maximum number of item send for debugging, plus 1.

Definition at line 175 of file pk.h.

Typedef Documentation

mbedtls_pk_rsassa_pss_options

typedef struct mbedtls_pk_rsassa_pss_options mbedtls_pk_rsassa_pss_options

Options for RSASSA-PSS signature verification.

See mbedtls_rsa_rsassa_pss_verify_ext()

mbedtls_pk_debug_item

typedef struct mbedtls_pk_debug_item mbedtls_pk_debug_item

Item to send to the debug module.

mbedtls_pk_info_t

typedef struct mbedtls_pk_info_t mbedtls_pk_info_t

Public key information and operations.

Definition at line 180 of file pk.h.

mbedtls_pk_context

typedef struct mbedtls_pk_context mbedtls_pk_context

Public key container.

Enumeration Type Documentation

mbedtls_pk_type_t

enum mbedtls_pk_type_t

Public key types.

Enumerator
MBEDTLS_PK_NONE	None.
MBEDTLS_PK_RSA	RSA.
MBEDTLS_PK_ECKEY	ECKEY.
MBEDTLS_PK_ECKEY_DH	ECKEY DH.
MBEDTLS_PK_ECDSA	ECDSA.
MBEDTLS_PK_RSA_ALT	RSA Alt.
MBEDTLS_PK_RSASSA_PSS	RSASSA PSS.
MBEDTLS_PK_OPAQUE	OPAQUE.

Definition at line 80 of file pk.h.

mbedtls_pk_debug_type

enum mbedtls_pk_debug_type

Types for interfacing with the debug module.

Definition at line 157 of file pk.h.

Function Documentation

mbedtls_pk_info_from_type()

const mbedtls_pk_info_t * mbedtls_pk_info_from_type

(

mbedtls_pk_type_t

pk_type

)

Return information associated with the given PK type.

Parameters

pk_type

PK type to search for.

Returns

The PK info associated with the type or NULL if not found.

mbedtls_pk_init()

void mbedtls_pk_init

(

mbedtls_pk_context *

ctx

)

Initialize a mbedtls_pk_context (as NONE).

Parameters

ctx	The context to initialize. This must not be NULL.

mbedtls_pk_free()

void mbedtls_pk_free

(

mbedtls_pk_context *

ctx

)

Free the components of a mbedtls_pk_context.

Parameters

ctx	The context to clear. It must have been initialized. If this is NULL, this function does nothing.

Note

For contexts that have been set up with mbedtls_pk_setup_opaque(), this does not free the underlying PSA key and you still need to call psa_destroy_key() independently if you want to destroy that key.

mbedtls_pk_setup()

int mbedtls_pk_setup	(	mbedtls_pk_context *	ctx,
		const mbedtls_pk_info_t *	info
	)

Initialize a PK context with the information given and allocates the type-specific PK subcontext.

Parameters

ctx	Context to initialize. It must not have been set up yet (type MBEDTLS_PK_NONE).
info	Information to use

Returns

0 on success, MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input, MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.

Note

For contexts holding an RSA-alt key, use mbedtls_pk_setup_rsa_alt() instead.

mbedtls_pk_get_bitlen()

size_t mbedtls_pk_get_bitlen

(

const mbedtls_pk_context *

ctx

)

Get the size in bits of the underlying key.

Parameters

ctx	The context to query. It must have been initialized.

Returns

Key size in bits, or 0 on error

mbedtls_pk_can_do()

int mbedtls_pk_can_do	(	const mbedtls_pk_context *	ctx,
		mbedtls_pk_type_t	type
	)

Tell if a context can do the operation given by type.

Parameters

ctx	The context to query. It must have been initialized.
type	The desired type.

Returns

1 if the context can do operations on the given type.

0 if the context cannot do the operations on the given type. This is always the case for a context that has been initialized but not set up, or that has been cleared with mbedtls_pk_free().

mbedtls_pk_verify()

int mbedtls_pk_verify	(	mbedtls_pk_context *	ctx,
		mbedtls_md_type_t	md_alg,
		const unsigned char *	hash,
		size_t	hash_len,
		const unsigned char *	sig,
		size_t	sig_len
	)

Verify signature (including padding if relevant).

Parameters

ctx	The PK context to use. It must have been set up.
md_alg	Hash algorithm used (see notes)
hash	Hash of the message to sign
hash_len	Hash length or 0 (see notes)
sig	Signature to verify
sig_len	Signature length

Returns

0 on success (signature is valid), MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid signature in sig but its length is less than siglen, or a specific error code.

Note

For RSA keys, the default padding type is PKCS#1 v1.5. Use mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... ) to verify RSASSA_PSS signatures.

If hash_len is 0, then the length associated with md_alg is used instead, or an error returned if it is invalid.

md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0

mbedtls_pk_verify_restartable()

int mbedtls_pk_verify_restartable	(	mbedtls_pk_context *	ctx,
		mbedtls_md_type_t	md_alg,
		const unsigned char *	hash,
		size_t	hash_len,
		const unsigned char *	sig,
		size_t	sig_len,
		mbedtls_pk_restart_ctx *	rs_ctx
	)

Restartable version of mbedtls_pk_verify()

Note

Performs the same job as mbedtls_pk_verify(), but can return early and restart according to the limit set with mbedtls_ecp_set_max_ops() to reduce blocking for ECC operations. For RSA, same as mbedtls_pk_verify().

Parameters

ctx	The PK context to use. It must have been set up.
md_alg	Hash algorithm used (see notes)
hash	Hash of the message to sign
hash_len	Hash length or 0 (see notes)
sig	Signature to verify
sig_len	Signature length
rs_ctx	Restart context (NULL to disable restart)

Returns

See mbedtls_pk_verify(), or

MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of operations was reached: see mbedtls_ecp_set_max_ops().

mbedtls_pk_verify_ext()

int mbedtls_pk_verify_ext	(	mbedtls_pk_type_t	type,
		const void *	options,
		mbedtls_pk_context *	ctx,
		mbedtls_md_type_t	md_alg,
		const unsigned char *	hash,
		size_t	hash_len,
		const unsigned char *	sig,
		size_t	sig_len
	)

Verify signature, with options.

(Includes verification of the padding depending on type.)

Parameters

type	Signature type (inc. possible padding type) to verify
options	Pointer to type-specific options, or NULL
ctx	The PK context to use. It must have been set up.
md_alg	Hash algorithm used (see notes)
hash	Hash of the message to sign
hash_len	Hash length or 0 (see notes)
sig	Signature to verify
sig_len	Signature length

Returns

0 on success (signature is valid), MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be used for this type of signatures, MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid signature in sig but its length is less than siglen, or a specific error code.

Note

If hash_len is 0, then the length associated with md_alg is used instead, or an error returned if it is invalid.

md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0

If type is MBEDTLS_PK_RSASSA_PSS, then options must point to a mbedtls_pk_rsassa_pss_options structure, otherwise it must be NULL.

mbedtls_pk_sign()

int mbedtls_pk_sign	(	mbedtls_pk_context *	ctx,
		mbedtls_md_type_t	md_alg,
		const unsigned char *	hash,
		size_t	hash_len,
		unsigned char *	sig,
		size_t *	sig_len,
		int(*)(void *, unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Make signature, including padding if relevant.

Parameters

ctx	The PK context to use. It must have been set up with a private key.
md_alg	Hash algorithm used (see notes)
hash	Hash of the message to sign
hash_len	Hash length or 0 (see notes)
sig	Place to write the signature. It must have enough room for the signature. MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough. You may use a smaller buffer if it is large enough given the key type.
sig_len	On successful return, the number of bytes written to sig.
f_rng	RNG function
p_rng	RNG parameter

Returns

0 on success, or a specific error code.

Note

For RSA keys, the default padding type is PKCS#1 v1.5. There is no interface in the PK module to make RSASSA-PSS signatures yet.

If hash_len is 0, then the length associated with md_alg is used instead, or an error returned if it is invalid.

For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0. For ECDSA, md_alg may never be MBEDTLS_MD_NONE.

mbedtls_pk_sign_restartable()

int mbedtls_pk_sign_restartable	(	mbedtls_pk_context *	ctx,
		mbedtls_md_type_t	md_alg,
		const unsigned char *	hash,
		size_t	hash_len,
		unsigned char *	sig,
		size_t *	sig_len,
		int(*)(void *, unsigned char *, size_t)	f_rng,
		void *	p_rng,
		mbedtls_pk_restart_ctx *	rs_ctx
	)

Restartable version of mbedtls_pk_sign()

Note

Performs the same job as mbedtls_pk_sign(), but can return early and restart according to the limit set with mbedtls_ecp_set_max_ops() to reduce blocking for ECC operations. For RSA, same as mbedtls_pk_sign().

Parameters

ctx	The PK context to use. It must have been set up with a private key.
md_alg	Hash algorithm used (see notes for mbedtls_pk_sign())
hash	Hash of the message to sign
hash_len	Hash length or 0 (see notes for mbedtls_pk_sign())
sig	Place to write the signature. It must have enough room for the signature. MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough. You may use a smaller buffer if it is large enough given the key type.
sig_len	On successful return, the number of bytes written to sig.
f_rng	RNG function
p_rng	RNG parameter
rs_ctx	Restart context (NULL to disable restart)

Returns

See mbedtls_pk_sign().

MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of operations was reached: see mbedtls_ecp_set_max_ops().

mbedtls_pk_decrypt()

int mbedtls_pk_decrypt	(	mbedtls_pk_context *	ctx,
		const unsigned char *	input,
		size_t	ilen,
		unsigned char *	output,
		size_t *	olen,
		size_t	osize,
		int(*)(void *, unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Decrypt message (including padding if relevant).

Parameters

ctx	The PK context to use. It must have been set up with a private key.
input	Input to decrypt
ilen	Input size
output	Decrypted output
olen	Decrypted message length
osize	Size of the output buffer
f_rng	RNG function
p_rng	RNG parameter

Note

For RSA keys, the default padding type is PKCS#1 v1.5.

Returns

0 on success, or a specific error code.

mbedtls_pk_encrypt()

int mbedtls_pk_encrypt	(	mbedtls_pk_context *	ctx,
		const unsigned char *	input,
		size_t	ilen,
		unsigned char *	output,
		size_t *	olen,
		size_t	osize,
		int(*)(void *, unsigned char *, size_t)	f_rng,
		void *	p_rng
	)

Encrypt message (including padding if relevant).

Parameters

ctx	The PK context to use. It must have been set up.
input	Message to encrypt
ilen	Message size
output	Encrypted output
olen	Encrypted output length
osize	Size of the output buffer
f_rng	RNG function
p_rng	RNG parameter

Note

For RSA keys, the default padding type is PKCS#1 v1.5.

Returns

0 on success, or a specific error code.

mbedtls_pk_check_pair()

int mbedtls_pk_check_pair	(	const mbedtls_pk_context *	pub,
		const mbedtls_pk_context *	prv
	)

Check if a public-private pair of keys matches.

Parameters

pub	Context holding a public key.
prv	Context holding a private (and public) key.

Returns

0 on success (keys were checked and match each other).

MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not be checked - in that case they may or may not match.

MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.

Another non-zero value if the keys do not match.

mbedtls_pk_debug()

int mbedtls_pk_debug	(	const mbedtls_pk_context *	ctx,
		mbedtls_pk_debug_item *	items
	)

Export debug information.

Parameters

ctx	The PK context to use. It must have been initialized.
items	Place to write debug items

Returns

0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA

mbedtls_pk_get_name()

const char * mbedtls_pk_get_name

(

const mbedtls_pk_context *

ctx

)

Access the type name.

Parameters

ctx	The PK context to use. It must have been initialized.

Returns

Type name on success, or "invalid PK"

mbedtls_pk_get_type()

mbedtls_pk_type_t mbedtls_pk_get_type

(

const mbedtls_pk_context *

ctx

)

Get the key type.

Parameters

ctx	The PK context to use. It must have been initialized.

Returns

Type on success.

MBEDTLS_PK_NONE for a context that has not been set up.