mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-11-24 00:18:26 +00:00
291 lines
7.7 KiB
C
291 lines
7.7 KiB
C
#define ECRYPT_VARIANT 1
|
|
#define ECRYPT_API
|
|
/* ecrypt-sync.h */
|
|
|
|
/*
|
|
* Header file for synchronous stream ciphers without authentication
|
|
* mechanism.
|
|
*
|
|
* *** Please only edit parts marked with "[edit]". ***
|
|
*/
|
|
|
|
#ifndef ECRYPT_SYNC
|
|
#define ECRYPT_SYNC
|
|
|
|
#include "ecrypt-types.h"
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* Cipher parameters */
|
|
|
|
/*
|
|
* The name of your cipher.
|
|
*/
|
|
#define ECRYPT_NAME "ChaCha20"
|
|
#define ECRYPT_PROFILE "_____"
|
|
|
|
/*
|
|
* Specify which key and IV sizes are supported by your cipher. A user
|
|
* should be able to enumerate the supported sizes by running the
|
|
* following code:
|
|
*
|
|
* for (i = 0; ECRYPT_KEYSIZE(i) <= ECRYPT_MAXKEYSIZE; ++i)
|
|
* {
|
|
* keysize = ECRYPT_KEYSIZE(i);
|
|
*
|
|
* ...
|
|
* }
|
|
*
|
|
* All sizes are in bits.
|
|
*/
|
|
|
|
#define ECRYPT_MAXKEYSIZE 256 /* [edit] */
|
|
#define ECRYPT_KEYSIZE(i) (128 + (i)*128) /* [edit] */
|
|
|
|
#define ECRYPT_MAXIVSIZE 64 /* [edit] */
|
|
#define ECRYPT_IVSIZE(i) (64 + (i)*64) /* [edit] */
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* Data structures */
|
|
|
|
/*
|
|
* ECRYPT_ctx is the structure containing the representation of the
|
|
* internal state of your cipher.
|
|
*/
|
|
|
|
typedef struct
|
|
{
|
|
u32 input[16]; /* could be compressed */
|
|
/*
|
|
* [edit]
|
|
*
|
|
* Put here all state variable needed during the encryption process.
|
|
*/
|
|
} ECRYPT_ctx;
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* Mandatory functions */
|
|
|
|
/*
|
|
* Key and message independent initialization. This function will be
|
|
* called once when the program starts (e.g., to build expanded S-box
|
|
* tables).
|
|
*/
|
|
void ECRYPT_init(void);
|
|
|
|
/*
|
|
* Key setup. It is the user's responsibility to select the values of
|
|
* keysize and ivsize from the set of supported values specified
|
|
* above.
|
|
*/
|
|
void ECRYPT_keysetup(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* key,
|
|
u32 keysize, /* Key size in bits. */
|
|
u32 ivsize); /* IV size in bits. */
|
|
|
|
/*
|
|
* IV setup. After having called ECRYPT_keysetup(), the user is
|
|
* allowed to call ECRYPT_ivsetup() different times in order to
|
|
* encrypt/decrypt different messages with the same key but different
|
|
* IV's. ECRYPT_ivsetup() also sets block counter to zero.
|
|
*/
|
|
void ECRYPT_ivsetup(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* iv);
|
|
|
|
/*
|
|
* Block counter setup. It is used only for special purposes,
|
|
* since block counter is usually initialized with ECRYPT_ivsetup.
|
|
* ECRYPT_ctrsetup has to be called after ECRYPT_ivsetup.
|
|
*/
|
|
void ECRYPT_ctrsetup(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* ctr);
|
|
|
|
/*
|
|
* Encryption/decryption of arbitrary length messages.
|
|
*
|
|
* For efficiency reasons, the API provides two types of
|
|
* encrypt/decrypt functions. The ECRYPT_encrypt_bytes() function
|
|
* (declared here) encrypts byte strings of arbitrary length, while
|
|
* the ECRYPT_encrypt_blocks() function (defined later) only accepts
|
|
* lengths which are multiples of ECRYPT_BLOCKLENGTH.
|
|
*
|
|
* The user is allowed to make multiple calls to
|
|
* ECRYPT_encrypt_blocks() to incrementally encrypt a long message,
|
|
* but he is NOT allowed to make additional encryption calls once he
|
|
* has called ECRYPT_encrypt_bytes() (unless he starts a new message
|
|
* of course). For example, this sequence of calls is acceptable:
|
|
*
|
|
* ECRYPT_keysetup();
|
|
*
|
|
* ECRYPT_ivsetup();
|
|
* ECRYPT_encrypt_blocks();
|
|
* ECRYPT_encrypt_blocks();
|
|
* ECRYPT_encrypt_bytes();
|
|
*
|
|
* ECRYPT_ivsetup();
|
|
* ECRYPT_encrypt_blocks();
|
|
* ECRYPT_encrypt_blocks();
|
|
*
|
|
* ECRYPT_ivsetup();
|
|
* ECRYPT_encrypt_bytes();
|
|
*
|
|
* The following sequence is not:
|
|
*
|
|
* ECRYPT_keysetup();
|
|
* ECRYPT_ivsetup();
|
|
* ECRYPT_encrypt_blocks();
|
|
* ECRYPT_encrypt_bytes();
|
|
* ECRYPT_encrypt_blocks();
|
|
*/
|
|
|
|
void ECRYPT_encrypt_bytes(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* plaintext,
|
|
u8* ciphertext,
|
|
u32 msglen); /* Message length in bytes. */
|
|
|
|
void ECRYPT_decrypt_bytes(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* ciphertext,
|
|
u8* plaintext,
|
|
u32 msglen); /* Message length in bytes. */
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* Optional features */
|
|
|
|
/*
|
|
* For testing purposes it can sometimes be useful to have a function
|
|
* which immediately generates keystream without having to provide it
|
|
* with a zero plaintext. If your cipher cannot provide this function
|
|
* (e.g., because it is not strictly a synchronous cipher), please
|
|
* reset the ECRYPT_GENERATES_KEYSTREAM flag.
|
|
*/
|
|
|
|
#define ECRYPT_GENERATES_KEYSTREAM
|
|
#ifdef ECRYPT_GENERATES_KEYSTREAM
|
|
|
|
void ECRYPT_keystream_bytes(
|
|
ECRYPT_ctx* ctx,
|
|
u8* keystream,
|
|
u32 length); /* Length of keystream in bytes. */
|
|
|
|
#endif
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
/* Optional optimizations */
|
|
|
|
/*
|
|
* By default, the functions in this section are implemented using
|
|
* calls to functions declared above. However, you might want to
|
|
* implement them differently for performance reasons.
|
|
*/
|
|
|
|
/*
|
|
* All-in-one encryption/decryption of (short) packets.
|
|
*
|
|
* The default definitions of these functions can be found in
|
|
* "ecrypt-sync.c". If you want to implement them differently, please
|
|
* undef the ECRYPT_USES_DEFAULT_ALL_IN_ONE flag.
|
|
*/
|
|
#define ECRYPT_USES_DEFAULT_ALL_IN_ONE /* [edit] */
|
|
|
|
void ECRYPT_encrypt_packet(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* iv,
|
|
const u8* plaintext,
|
|
u8* ciphertext,
|
|
u32 msglen);
|
|
|
|
void ECRYPT_decrypt_packet(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* iv,
|
|
const u8* ciphertext,
|
|
u8* plaintext,
|
|
u32 msglen);
|
|
|
|
/*
|
|
* Encryption/decryption of blocks.
|
|
*
|
|
* By default, these functions are defined as macros. If you want to
|
|
* provide a different implementation, please undef the
|
|
* ECRYPT_USES_DEFAULT_BLOCK_MACROS flag and implement the functions
|
|
* declared below.
|
|
*/
|
|
|
|
#define ECRYPT_BLOCKLENGTH 64 /* [edit] */
|
|
|
|
#define ECRYPT_USES_DEFAULT_BLOCK_MACROS /* [edit] */
|
|
#ifdef ECRYPT_USES_DEFAULT_BLOCK_MACROS
|
|
|
|
#define ECRYPT_encrypt_blocks(ctx, plaintext, ciphertext, blocks) \
|
|
ECRYPT_encrypt_bytes(ctx, plaintext, ciphertext, \
|
|
(blocks) * ECRYPT_BLOCKLENGTH)
|
|
|
|
#define ECRYPT_decrypt_blocks(ctx, ciphertext, plaintext, blocks) \
|
|
ECRYPT_decrypt_bytes(ctx, ciphertext, plaintext, \
|
|
(blocks) * ECRYPT_BLOCKLENGTH)
|
|
|
|
#ifdef ECRYPT_GENERATES_KEYSTREAM
|
|
|
|
#define ECRYPT_keystream_blocks(ctx, keystream, blocks) \
|
|
ECRYPT_keystream_bytes(ctx, keystream, \
|
|
(blocks) * ECRYPT_BLOCKLENGTH)
|
|
|
|
#endif
|
|
|
|
#else
|
|
|
|
void ECRYPT_encrypt_blocks(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* plaintext,
|
|
u8* ciphertext,
|
|
u32 blocks); /* Message length in blocks. */
|
|
|
|
void ECRYPT_decrypt_blocks(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* ciphertext,
|
|
u8* plaintext,
|
|
u32 blocks); /* Message length in blocks. */
|
|
|
|
#ifdef ECRYPT_GENERATES_KEYSTREAM
|
|
|
|
void ECRYPT_keystream_blocks(
|
|
ECRYPT_ctx* ctx,
|
|
const u8* keystream,
|
|
u32 blocks); /* Keystream length in blocks. */
|
|
|
|
#endif
|
|
|
|
#endif
|
|
|
|
/*
|
|
* If your cipher can be implemented in different ways, you can use
|
|
* the ECRYPT_VARIANT parameter to allow the user to choose between
|
|
* them at compile time (e.g., gcc -DECRYPT_VARIANT=3 ...). Please
|
|
* only use this possibility if you really think it could make a
|
|
* significant difference and keep the number of variants
|
|
* (ECRYPT_MAXVARIANT) as small as possible (definitely not more than
|
|
* 10). Note also that all variants should have exactly the same
|
|
* external interface (i.e., the same ECRYPT_BLOCKLENGTH, etc.).
|
|
*/
|
|
#define ECRYPT_MAXVARIANT 1 /* [edit] */
|
|
|
|
#ifndef ECRYPT_VARIANT
|
|
#define ECRYPT_VARIANT 1
|
|
#endif
|
|
|
|
#if (ECRYPT_VARIANT > ECRYPT_MAXVARIANT)
|
|
#error this variant does not exist
|
|
#endif
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
#endif
|