openssh/chacha.h
Damien Miller 0fde8acdad - djm@cvs.openbsd.org 2013/11/21 00:45:44
[Makefile.in PROTOCOL PROTOCOL.chacha20poly1305 authfile.c chacha.c]
     [chacha.h cipher-chachapoly.c cipher-chachapoly.h cipher.c cipher.h]
     [dh.c myproposal.h packet.c poly1305.c poly1305.h servconf.c ssh.1]
     [ssh.c ssh_config.5 sshd_config.5] Add a new protocol 2 transport
     cipher "chacha20-poly1305@openssh.com" that combines Daniel
     Bernstein's ChaCha20 stream cipher and Poly1305 MAC to build an
     authenticated encryption mode.

     Inspired by and similar to Adam Langley's proposal for TLS:
     http://tools.ietf.org/html/draft-agl-tls-chacha20poly1305-03
     but differs in layout used for the MAC calculation and the use of a
     second ChaCha20 instance to separately encrypt packet lengths.
     Details are in the PROTOCOL.chacha20poly1305 file.

     Feedback markus@, naddy@; manpage bits Loganden Velvindron @ AfriNIC
     ok markus@ naddy@
2013-11-21 14:12:23 +11:00

36 lines
975 B
C

/* $OpenBSD: chacha.h,v 1.1 2013/11/21 00:45:44 djm Exp $ */
/*
chacha-merged.c version 20080118
D. J. Bernstein
Public domain.
*/
#ifndef CHACHA_H
#define CHACHA_H
#include <sys/types.h>
struct chacha_ctx {
u_int input[16];
};
#define CHACHA_MINKEYLEN 16
#define CHACHA_NONCELEN 8
#define CHACHA_CTRLEN 8
#define CHACHA_STATELEN (CHACHA_NONCELEN+CHACHA_CTRLEN)
#define CHACHA_BLOCKLEN 64
void chacha_keysetup(struct chacha_ctx *x, const u_char *k, u_int kbits)
__attribute__((__bounded__(__minbytes__, 2, CHACHA_MINKEYLEN)));
void chacha_ivsetup(struct chacha_ctx *x, const u_char *iv, const u_char *ctr)
__attribute__((__bounded__(__minbytes__, 2, CHACHA_NONCELEN)))
__attribute__((__bounded__(__minbytes__, 3, CHACHA_CTRLEN)));
void chacha_encrypt_bytes(struct chacha_ctx *x, const u_char *m,
u_char *c, u_int bytes)
__attribute__((__bounded__(__buffer__, 2, 4)))
__attribute__((__bounded__(__buffer__, 3, 4)));
#endif /* CHACHA_H */