SIGNING

ED25519 signature functions. More...

Functions
byte *	pcp_ed_sign (byte *message, size_t messagesize, pcp_key_t *s)
	Sign a raw message. More...
byte *	pcp_ed_sign_key (byte *message, size_t messagesize, pcp_key_t *s)
	Sign a raw message using s->mastersecret. More...
byte *	pcp_ed_verify (PCPCTX *ptx, byte *signature, size_t siglen, pcp_pubkey_t *p)
	Verify a signature. More...
byte *	pcp_ed_verify_key (PCPCTX *ptx, byte *signature, size_t siglen, pcp_pubkey_t *p)
	Verify a signature using the mastersecret. More...
size_t	pcp_ed_sign_buffered (PCPCTX *ptx, Pcpstream *in, Pcpstream *out, pcp_key_t *s, int z85)
	Sign a stream in 32k block mode. More...
pcp_pubkey_t *	pcp_ed_verify_buffered (PCPCTX *ptx, Pcpstream *in, pcp_pubkey_t *p)
	Verify a signature from a stream in 32k block mode. More...
size_t	pcp_ed_detachsign_buffered (Pcpstream *in, Pcpstream *out, pcp_key_t *s)
	Generate a detached signature from a stream in 32k block mode. More...
pcp_pubkey_t *	pcp_ed_detachverify_buffered (PCPCTX *ptx, Pcpstream *in, Pcpstream *sigfd, pcp_pubkey_t *p)
	Verify a detached signature from a stream in 32k block mode. More...

Detailed Description

ED25519 signature functions.

Function Documentation

size_t pcp_ed_detachsign_buffered	(	Pcpstream *	in,
		Pcpstream *	out,
		pcp_key_t *	s
	)

Generate a detached signature from a stream in 32k block mode.

This function reads blockwise from the stream in and generates a hash of the contents of the stream. It then signs that hash and writes the hash and the signature to the output stream out.

Parameters

[in]	in	Stream to read from.
[out]	out	Stream to write to.
[in]	s	Pointer to secret key.

Returns

Returns the size of the detached signature written or 0 in case of errors. Check fatals_if_any().

pcp_pubkey_t* pcp_ed_detachverify_buffered	(	PCPCTX *	ptx,
		Pcpstream *	in,
		Pcpstream *	sigfd,
		pcp_pubkey_t *	p
	)

Verify a detached signature from a stream in 32k block mode.

This function reads blockwise from the stream in and generates a hash of the contents of the stream. It then reads the signature from the stream sigfd and verifies the signature from it using p->edpub and compares the signature hash with the hash it calculated from the signed content.

Parameters

[in]	ptx	pcp context.
[in]	in	Stream to read from.
[in]	sigfd	Stream containing the detached signature.
[in]	p	Pointer to public key structure.

Returns

Returns a pointer to a public key which were used to verify the signature or NULL if an error occurred. Check fatals_if_any().

byte* pcp_ed_sign	(	byte *	message,
		size_t	messagesize,
		pcp_key_t *	s
	)

Sign a raw message.

Sign a message of messagesize using s->edsecret. This is just a convenience wrapper around crypto_sign().

Parameters

[in]	message	The message to sign.
[in]	messagesize	Size of the message.
[in]	s	Pointer to secret key structure.

Returns

Returns message+signature with size of messagesize + crypto_sign_BYTES, or NULL in case of an error.

size_t pcp_ed_sign_buffered	(	PCPCTX *	ptx,
		Pcpstream *	in,
		Pcpstream *	out,
		pcp_key_t *	s,
		int	z85
	)

Sign a stream in 32k block mode.

This function reads blockwise from the stream in and generates a hash of the contents of the stream. It outputs the stream to out, also blockwise and appends the signature afterwards, which consists of the hash+nacl-signature.

Parameters

[in]	ptx	pcp context.
[in]	in	Stream to read from.
[out]	out	Stream to write to.
[in]	s	Pointer to secret key.
[in]	z85	Flag which indicates if to create an armored signature or not. 1=armored, 0=raw.

Returns

Returns the number of bytes written to the output stream.

byte* pcp_ed_sign_key	(	byte *	message,
		size_t	messagesize,
		pcp_key_t *	s
	)

Sign a raw message using s->mastersecret.

The same as pcp_ed_sign() but uses the mastersecret for signing. Usually used for key signing only.

Parameters

[in]	message	The message to sign.
[in]	messagesize	Size of the message.
[in]	s	Pointer to secret key structure.

Returns

Returns message+signature with size of messagesize + crypto_sign_BYTES, or NULL in case of an error.

byte* pcp_ed_verify	(	PCPCTX *	ptx,
		byte *	signature,
		size_t	siglen,
		pcp_pubkey_t *	p
	)

Verify a signature.

Verify a signature of size siglen using p->edpub.

The signature must contain the message+nacl signature (with size crypto_sign_BYTES).

Parameters

[in]	ptx	pcp context.
[in]	signature	Message+signature.
[in]	siglen	Size of message+signature.
[in]	p	Pointer to public key structure.

Returns

If the signature verifies return the raw message with the signature removed (size: siglen - crypto_sign_BYTES), returns NULL in case of errors. Check fatals_if_any().

pcp_pubkey_t* pcp_ed_verify_buffered	(	PCPCTX *	ptx,
		Pcpstream *	in,
		pcp_pubkey_t *	p
	)

Verify a signature from a stream in 32k block mode.

This function reads blockwise from the stream in and generates a hash of the contents of the stream. While reading from the stream it extracts the appended signature (hash+sig). It then verifies the signature using p->edpub and compares the signature hash with the hash it calculated from the signed content.

The parameter p can be NULL. In this case the function loops through the global public key hash pcppubkey_hash to find a public key which is able to verify the signature.

Parameters

[in]	ptx	pcp context.
[in]	in	Stream to read from.
[in]	p	Pointer to public key structure.

Returns

Returns a pointer to a public key which were used to verify the signature or NULL if an error occurred. Check fatals_if_any().

byte* pcp_ed_verify_key	(	PCPCTX *	ptx,
		byte *	signature,
		size_t	siglen,
		pcp_pubkey_t *	p
	)

Verify a signature using the mastersecret.

Verify a signature of size siglen using p->masterpub.

The signature must contain the message+nacl signature (with size crypto_sign_BYTES).

Parameters

[in]	ptx	pcp context.
[in]	signature	Message+signature.
[in]	siglen	Size of message+signature.
[in]	p	Pointer to public key structure.

Returns

If the signature verifies return the raw message with the signature removed (size: siglen - crypto_sign_BYTES), returns NULL in case of errors. Check fatals_if_any().