relay_crypto_cgo.h File Reference

Header file for relay_crypto_cgo.c. More...

#include "lib/testsupport/testsupport.h"

Go to the source code of this file.

Macros
#define	CGO_TAG_LEN   16
#define	cgo_crypt_free(cgo)    FREE_AND_NULL(cgo_crypt_t, cgo_crypt_free_, (cgo))

Typedefs
typedef struct cgo_crypt_t	cgo_crypt_t

Enumerations
enum	cgo_mode_t { CGO_MODE_CLIENT_FORWARD , CGO_MODE_CLIENT_BACKWARD , CGO_MODE_RELAY_FORWARD , CGO_MODE_RELAY_BACKWARD }

Functions
size_t	cgo_key_material_len (int aesbits)
cgo_crypt_t *	cgo_crypt_new (cgo_mode_t mode, int aesbits, const uint8_t *keys, size_t keylen)
void	cgo_crypt_free_ (cgo_crypt_t *cgo)
void	cgo_crypt_relay_forward (cgo_crypt_t *cgo, struct cell_t *cell, const uint8_t **recognized_tag_out)
void	cgo_crypt_relay_backward (cgo_crypt_t *cgo, struct cell_t *cell)
void	cgo_crypt_relay_originate (cgo_crypt_t *cgo, struct cell_t *cell, const uint8_t **tag_out)
void	cgo_crypt_client_forward (cgo_crypt_t *cgo, struct cell_t *cell)
void	cgo_crypt_client_originate (cgo_crypt_t *cgo, struct cell_t *cell, const uint8_t **tag_out)
void	cgo_crypt_client_backward (cgo_crypt_t *cgo, struct cell_t *cell, const uint8_t **recognized_tag_out)

Detailed Description

Header file for relay_crypto_cgo.c.

Definition in file relay_crypto_cgo.h.

Macro Definition Documentation

cgo_crypt_free

#define cgo_crypt_free

(

cgo

)

FREE_AND_NULL(cgo_crypt_t, cgo_crypt_free_, (cgo))

Definition at line 45 of file relay_crypto_cgo.h.

CGO_TAG_LEN

#define CGO_TAG_LEN   16

Length of a CGO cell tag.

This is the value used for authenticated SENDMES.

Definition at line 37 of file relay_crypto_cgo.h.

Typedef Documentation

cgo_crypt_t

typedef struct cgo_crypt_t cgo_crypt_t

State to implement forward or reverse crypto between a client and a single hop on a circuit.

(There needs to be one of these for each direction.

Definition at line 23 of file relay_crypto_cgo.h.

Enumeration Type Documentation

cgo_mode_t

enum cgo_mode_t

Definition at line 25 of file relay_crypto_cgo.h.

Function Documentation

cgo_crypt_client_backward()

void cgo_crypt_client_backward	(	cgo_crypt_t *	cgo,
		cell_t *	cell,
		const uint8_t **	recognized_tag_out
	)

Backward CGO encryption operation at a rclient. process an inbound cell from a relay.

If the cell originated from this this relay, set *'recognized_tag_out' to point to a CGO_TAG_LEN value that should be used if we want to acknowledge this cell with an authenticated SENDME.

The value of 'recognized_tag_out' will become invalid as soon as any change is made to this 'cgo' object, or to the cell; if you need it, you should copy it immediately.

If the cell is not from this relay, set *'recognized_tag_out' to NULL.

Definition at line 560 of file relay_crypto_cgo.c.

cgo_crypt_client_forward()

void cgo_crypt_client_forward	(	cgo_crypt_t *	cgo,
		cell_t *	cell
	)

Forward CGO encryption at a client: process a cell for a non-destination hop.

Definition at line 509 of file relay_crypto_cgo.c.

Referenced by cgo_crypt_client_originate().

cgo_crypt_client_originate()

void cgo_crypt_client_originate	(	cgo_crypt_t *	cgo,
		cell_t *	cell,
		const uint8_t **	tag_out
	)

Forward CGO encryption at a client: originate a cell for a given target hop.

The provided cell must have its command value set, and should have the first CGO_TAG_LEN bytes of its payload unused.

Set '*tag_out' to a value that we should expect if we want an authenticated SENDME for this cell.

The value of 'recognized_tag_out' will become invalid as soon as any change is made to this 'cgo' object, or to the cell; if you need it, you should copy it immediately.

Definition at line 536 of file relay_crypto_cgo.c.

cgo_crypt_free_()

void cgo_crypt_free_

(

cgo_crypt_t *

cgo

)

Clean up 'cgo' and free it.

Definition at line 403 of file relay_crypto_cgo.c.

cgo_crypt_new()

cgo_crypt_t * cgo_crypt_new	(	cgo_mode_t	mode,
		int	aesbits,
		const uint8_t *	keys,
		size_t	keylen
	)

Instantiate a CGO authenticated encryption object from the provided 'keylen' bytes in 'keys'.

'keylen' must equal 'cgo_key_material_len(aesbits)'.

The client and relay must have two cgo_crypt_t objects each: one for the forward direction, and one for the reverse direction.

Definition at line 377 of file relay_crypto_cgo.c.

cgo_crypt_relay_backward()

void cgo_crypt_relay_backward	(	cgo_crypt_t *	cgo,
		cell_t *	cell
	)

Backward CGO encryption operation at a relay: process an inbound cell from another relay, for the client.

Definition at line 461 of file relay_crypto_cgo.c.

cgo_crypt_relay_forward()

void cgo_crypt_relay_forward	(	cgo_crypt_t *	cgo,
		cell_t *	cell,
		const uint8_t **	recognized_tag_out
	)

Forward CGO encryption operation at a relay: process an outbound cell from the client.

If the cell is for this relay, set *'recognized_tag_out' to point to a CGO_TAG_LEN value that should be used if we want to acknowledge this cell with an authenticated SENDME.

The value of 'recognized_tag_out' will become invalid as soon as any change is made to this 'cgo' object, or to the cell; if you need it, you should copy it immediately.

If the cell is not for this relay, set *'recognized_tag_out' to NULL.

Definition at line 438 of file relay_crypto_cgo.c.

cgo_crypt_relay_originate()

void cgo_crypt_relay_originate	(	cgo_crypt_t *	cgo,
		cell_t *	cell,
		const uint8_t **	tag_out
	)

Backward CGO encryption operation at a relay: encrypt an inbound message that we are originating, for the client.

The provided cell must have its command value set, and should have the first CGO_TAG_LEN bytes of its payload unused.

Set '*tag_out' to a value that we should expect if we want an authenticated SENDME for this cell.

The value of 'recognized_tag_out' will become invalid as soon as any change is made to this 'cgo' object, or to the cell; if you need it, you should copy it immediately.

Definition at line 486 of file relay_crypto_cgo.c.

cgo_key_material_len()

size_t cgo_key_material_len

(

int

aesbits

)

Return the total number of bytes needed to initialize a cgo_crypt_t.

Definition at line 361 of file relay_crypto_cgo.c.

Referenced by cgo_crypt_new().