ASN.1 Write

Functions
int	mbedtls_asn1_write_len (unsigned char **p, unsigned char *start, size_t len)
	Write a length field in ASN.1 format. More...
int	mbedtls_asn1_write_tag (unsigned char **p, unsigned char *start, unsigned char tag)
	Write an ASN.1 tag in ASN.1 format. More...
int	mbedtls_asn1_write_raw_buffer (unsigned char **p, unsigned char *start, const unsigned char *buf, size_t size)
	Write raw buffer data. More...
int	mbedtls_asn1_write_null (unsigned char **p, unsigned char *start)
	Write a NULL tag (MBEDTLS_ASN1_NULL) with zero data in ASN.1 format. More...
int	mbedtls_asn1_write_oid (unsigned char **p, unsigned char *start, const char *oid, size_t oid_len)
	Write an OID tag (MBEDTLS_ASN1_OID) and data in ASN.1 format. More...
int	mbedtls_asn1_write_algorithm_identifier (unsigned char **p, unsigned char *start, const char *oid, size_t oid_len, size_t par_len)
	Write an AlgorithmIdentifier sequence in ASN.1 format. More...
int	mbedtls_asn1_write_bool (unsigned char **p, unsigned char *start, int boolean)
	Write a boolean tag (MBEDTLS_ASN1_BOOLEAN) and value in ASN.1 format. More...
int	mbedtls_asn1_write_int (unsigned char **p, unsigned char *start, int val)
	Write an int tag (MBEDTLS_ASN1_INTEGER) and value in ASN.1 format. More...
int	mbedtls_asn1_write_enum (unsigned char **p, unsigned char *start, int val)
	Write an enum tag (MBEDTLS_ASN1_ENUMERATED) and value in ASN.1 format. More...
int	mbedtls_asn1_write_tagged_string (unsigned char **p, unsigned char *start, int tag, const char *text, size_t text_len)
	Write a string in ASN.1 format using a specific string encoding tag. More...
int	mbedtls_asn1_write_printable_string (unsigned char **p, unsigned char *start, const char *text, size_t text_len)
	Write a string in ASN.1 format using the PrintableString string encoding tag (MBEDTLS_ASN1_PRINTABLE_STRING). More...
int	mbedtls_asn1_write_utf8_string (unsigned char **p, unsigned char *start, const char *text, size_t text_len)
	Write a UTF8 string in ASN.1 format using the UTF8String string encoding tag (MBEDTLS_ASN1_UTF8_STRING). More...
int	mbedtls_asn1_write_ia5_string (unsigned char **p, unsigned char *start, const char *text, size_t text_len)
	Write a string in ASN.1 format using the IA5String string encoding tag (MBEDTLS_ASN1_IA5_STRING). More...
int	mbedtls_asn1_write_bitstring (unsigned char **p, unsigned char *start, const unsigned char *buf, size_t bits)
	Write a bitstring tag (MBEDTLS_ASN1_BIT_STRING) and value in ASN.1 format. More...
int	mbedtls_asn1_write_named_bitstring (unsigned char **p, unsigned char *start, const unsigned char *buf, size_t bits)
	This function writes a named bitstring tag (MBEDTLS_ASN1_BIT_STRING) and value in ASN.1 format. More...
int	mbedtls_asn1_write_octet_string (unsigned char **p, unsigned char *start, const unsigned char *buf, size_t size)
	Write an octet string tag (MBEDTLS_ASN1_OCTET_STRING) and value in ASN.1 format. More...
mbedtls_asn1_named_data *	mbedtls_asn1_store_named_data (mbedtls_asn1_named_data **list, const char *oid, size_t oid_len, const unsigned char *val, size_t val_len)
	Create or find a specific named_data entry for writing in a sequence or list based on the OID. More...

Detailed Description

Function Documentation

mbedtls_asn1_write_len()

int mbedtls_asn1_write_len	(	unsigned char **	p,
		unsigned char *	start,
		size_t	len
	)

Write a length field in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
len	The length value to write.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_tag()

int mbedtls_asn1_write_tag	(	unsigned char **	p,
		unsigned char *	start,
		unsigned char	tag
	)

Write an ASN.1 tag in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
tag	The tag to write.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_raw_buffer()

int mbedtls_asn1_write_raw_buffer	(	unsigned char **	p,
		unsigned char *	start,
		const unsigned char *	buf,
		size_t	size
	)

Write raw buffer data.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
buf	The data buffer to write.
size	The length of the data buffer.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_null()

int mbedtls_asn1_write_null	(	unsigned char **	p,
		unsigned char *	start
	)

Write a NULL tag (MBEDTLS_ASN1_NULL) with zero data in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_oid()

int mbedtls_asn1_write_oid	(	unsigned char **	p,
		unsigned char *	start,
		const char *	oid,
		size_t	oid_len
	)

Write an OID tag (MBEDTLS_ASN1_OID) and data in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
oid	The OID to write.
oid_len	The length of the OID.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_algorithm_identifier()

int mbedtls_asn1_write_algorithm_identifier	(	unsigned char **	p,
		unsigned char *	start,
		const char *	oid,
		size_t	oid_len,
		size_t	par_len
	)

Write an AlgorithmIdentifier sequence in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
oid	The OID of the algorithm to write.
oid_len	The length of the algorithm's OID.
par_len	The length of the parameters, which must be already written. If 0, NULL parameters are added

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_bool()

int mbedtls_asn1_write_bool	(	unsigned char **	p,
		unsigned char *	start,
		int	boolean
	)

Write a boolean tag (MBEDTLS_ASN1_BOOLEAN) and value in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
boolean	The boolean value to write, either 0 or 1.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_int()

int mbedtls_asn1_write_int	(	unsigned char **	p,
		unsigned char *	start,
		int	val
	)

Write an int tag (MBEDTLS_ASN1_INTEGER) and value in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
val	The integer value to write. It must be non-negative.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_enum()

int mbedtls_asn1_write_enum	(	unsigned char **	p,
		unsigned char *	start,
		int	val
	)

Write an enum tag (MBEDTLS_ASN1_ENUMERATED) and value in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
val	The integer value to write.

Returns

The number of bytes written to p on success.

A negative MBEDTLS_ERR_ASN1_XXX error code on failure.

mbedtls_asn1_write_tagged_string()

int mbedtls_asn1_write_tagged_string	(	unsigned char **	p,
		unsigned char *	start,
		int	tag,
		const char *	text,
		size_t	text_len
	)

Write a string in ASN.1 format using a specific string encoding tag.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
tag	The string encoding tag to write, e.g. MBEDTLS_ASN1_UTF8_STRING.
text	The string to write.
text_len	The length of text in bytes (which might be strictly larger than the number of characters).

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_printable_string()

int mbedtls_asn1_write_printable_string	(	unsigned char **	p,
		unsigned char *	start,
		const char *	text,
		size_t	text_len
	)

Write a string in ASN.1 format using the PrintableString string encoding tag (MBEDTLS_ASN1_PRINTABLE_STRING).

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
text	The string to write.
text_len	The length of text in bytes (which might be strictly larger than the number of characters).

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_utf8_string()

int mbedtls_asn1_write_utf8_string	(	unsigned char **	p,
		unsigned char *	start,
		const char *	text,
		size_t	text_len
	)

Write a UTF8 string in ASN.1 format using the UTF8String string encoding tag (MBEDTLS_ASN1_UTF8_STRING).

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
text	The string to write.
text_len	The length of text in bytes (which might be strictly larger than the number of characters).

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_ia5_string()

int mbedtls_asn1_write_ia5_string	(	unsigned char **	p,
		unsigned char *	start,
		const char *	text,
		size_t	text_len
	)

Write a string in ASN.1 format using the IA5String string encoding tag (MBEDTLS_ASN1_IA5_STRING).

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
text	The string to write.
text_len	The length of text in bytes (which might be strictly larger than the number of characters).

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_bitstring()

int mbedtls_asn1_write_bitstring	(	unsigned char **	p,
		unsigned char *	start,
		const unsigned char *	buf,
		size_t	bits
	)

Write a bitstring tag (MBEDTLS_ASN1_BIT_STRING) and value in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
buf	The bitstring to write.
bits	The total number of bits in the bitstring.

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_named_bitstring()

int mbedtls_asn1_write_named_bitstring	(	unsigned char **	p,
		unsigned char *	start,
		const unsigned char *	buf,
		size_t	bits
	)

This function writes a named bitstring tag (MBEDTLS_ASN1_BIT_STRING) and value in ASN.1 format.

As stated in RFC 5280 Appendix B, trailing zeroes are omitted when encoding named bitstrings in DER.

Note

This function works backwards within the data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer which is used for bounds-checking.
buf	The bitstring to write.
bits	The total number of bits in the bitstring.

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_write_octet_string()

int mbedtls_asn1_write_octet_string	(	unsigned char **	p,
		unsigned char *	start,
		const unsigned char *	buf,
		size_t	size
	)

Write an octet string tag (MBEDTLS_ASN1_OCTET_STRING) and value in ASN.1 format.

Note

This function works backwards in data buffer.

Parameters

p	The reference to the current position pointer.
start	The start of the buffer, for bounds-checking.
buf	The buffer holding the data to write.
size	The length of the data buffer buf.

Returns

The number of bytes written to p on success.

A negative error code on failure.

mbedtls_asn1_store_named_data()

mbedtls_asn1_named_data * mbedtls_asn1_store_named_data	(	mbedtls_asn1_named_data **	list,
		const char *	oid,
		size_t	oid_len,
		const unsigned char *	val,
		size_t	val_len
	)

Create or find a specific named_data entry for writing in a sequence or list based on the OID.

If not already in there, a new entry is added to the head of the list. Warning: Destructive behaviour for the val data!

Parameters

list	The pointer to the location of the head of the list to seek through (will be updated in case of a new entry).
oid	The OID to look for.
oid_len	The size of the OID.
val	The associated data to store. If this is NULL, no data is copied to the new or existing buffer.
val_len	The minimum length of the data buffer needed. If this is 0, do not allocate a buffer for the associated data. If the OID was already present, enlarge, shrink or free the existing buffer to fit val_len.

Returns

A pointer to the new / existing entry on success.

NULL if if there was a memory allocation error.