diff options
Diffstat (limited to 'crypto/openssh/cipher-chachapoly.c')
| -rw-r--r-- | crypto/openssh/cipher-chachapoly.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/crypto/openssh/cipher-chachapoly.c b/crypto/openssh/cipher-chachapoly.c index 251b94e..7f31ff4 100644 --- a/crypto/openssh/cipher-chachapoly.c +++ b/crypto/openssh/cipher-chachapoly.c @@ -14,7 +14,7 @@ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ -/* $OpenBSD: cipher-chachapoly.c,v 1.4 2014/01/31 16:39:19 tedu Exp $ */ +/* $OpenBSD: cipher-chachapoly.c,v 1.7 2015/01/14 10:24:42 markus Exp $ */ #include "includes.h" @@ -24,16 +24,18 @@ #include <stdio.h> /* needed for misc.h */ #include "log.h" -#include "misc.h" +#include "sshbuf.h" +#include "ssherr.h" #include "cipher-chachapoly.h" -void chachapoly_init(struct chachapoly_ctx *ctx, +int chachapoly_init(struct chachapoly_ctx *ctx, const u_char *key, u_int keylen) { if (keylen != (32 + 32)) /* 2 x 256 bit keys */ - fatal("%s: invalid keylen %u", __func__, keylen); + return SSH_ERR_INVALID_ARGUMENT; chacha_keysetup(&ctx->main_ctx, key, 256); chacha_keysetup(&ctx->header_ctx, key + 32, 256); + return 0; } /* @@ -52,33 +54,37 @@ chachapoly_crypt(struct chachapoly_ctx *ctx, u_int seqnr, u_char *dest, u_char seqbuf[8]; const u_char one[8] = { 1, 0, 0, 0, 0, 0, 0, 0 }; /* NB little-endian */ u_char expected_tag[POLY1305_TAGLEN], poly_key[POLY1305_KEYLEN]; - int r = -1; + int r = SSH_ERR_INTERNAL_ERROR; /* * Run ChaCha20 once to generate the Poly1305 key. The IV is the * packet sequence number. */ memset(poly_key, 0, sizeof(poly_key)); - put_u64(seqbuf, seqnr); + POKE_U64(seqbuf, seqnr); chacha_ivsetup(&ctx->main_ctx, seqbuf, NULL); chacha_encrypt_bytes(&ctx->main_ctx, poly_key, poly_key, sizeof(poly_key)); - /* Set Chacha's block counter to 1 */ - chacha_ivsetup(&ctx->main_ctx, seqbuf, one); /* If decrypting, check tag before anything else */ if (!do_encrypt) { const u_char *tag = src + aadlen + len; poly1305_auth(expected_tag, src, aadlen + len, poly_key); - if (timingsafe_bcmp(expected_tag, tag, POLY1305_TAGLEN) != 0) + if (timingsafe_bcmp(expected_tag, tag, POLY1305_TAGLEN) != 0) { + r = SSH_ERR_MAC_INVALID; goto out; + } } + /* Crypt additional data */ if (aadlen) { chacha_ivsetup(&ctx->header_ctx, seqbuf, NULL); chacha_encrypt_bytes(&ctx->header_ctx, src, dest, aadlen); } + + /* Set Chacha's block counter to 1 */ + chacha_ivsetup(&ctx->main_ctx, seqbuf, one); chacha_encrypt_bytes(&ctx->main_ctx, src + aadlen, dest + aadlen, len); @@ -88,7 +94,6 @@ chachapoly_crypt(struct chachapoly_ctx *ctx, u_int seqnr, u_char *dest, poly_key); } r = 0; - out: explicit_bzero(expected_tag, sizeof(expected_tag)); explicit_bzero(seqbuf, sizeof(seqbuf)); @@ -104,11 +109,10 @@ chachapoly_get_length(struct chachapoly_ctx *ctx, u_char buf[4], seqbuf[8]; if (len < 4) - return -1; /* Insufficient length */ - put_u64(seqbuf, seqnr); + return SSH_ERR_MESSAGE_INCOMPLETE; + POKE_U64(seqbuf, seqnr); chacha_ivsetup(&ctx->header_ctx, seqbuf, NULL); chacha_encrypt_bytes(&ctx->header_ctx, cp, buf, 4); - *plenp = get_u32(buf); + *plenp = PEEK_U32(buf); return 0; } - |
