diff options
Diffstat (limited to 'cipher')
| -rw-r--r-- | cipher/chacha20.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/cipher/chacha20.c b/cipher/chacha20.c index c1847aa5..2eaeffde 100644 --- a/cipher/chacha20.c +++ b/cipher/chacha20.c @@ -45,6 +45,7 @@ #define CHACHA20_BLOCK_SIZE 64 /* Bytes. */ #define CHACHA20_MIN_IV_SIZE 8 /* Bytes. */ #define CHACHA20_MAX_IV_SIZE 12 /* Bytes. */ +#define CHACHA20_CTR_SIZE 16 /* Bytes. */ #define CHACHA20_INPUT_LENGTH (CHACHA20_BLOCK_SIZE / 4) /* USE_SSE2 indicates whether to compile with Intel SSE2 code. */ @@ -312,22 +313,30 @@ chacha20_keysetup (CHACHA20_context_t * ctx, const byte * key, static void chacha20_ivsetup (CHACHA20_context_t * ctx, const byte * iv, size_t ivlen) { - ctx->input[12] = 0; - - if (ivlen == CHACHA20_MAX_IV_SIZE) + if (ivlen == CHACHA20_CTR_SIZE) + { + ctx->input[12] = buf_get_le32 (iv + 0); + ctx->input[13] = buf_get_le32 (iv + 4); + ctx->input[14] = buf_get_le32 (iv + 8); + ctx->input[15] = buf_get_le32 (iv + 12); + } + else if (ivlen == CHACHA20_MAX_IV_SIZE) { + ctx->input[12] = 0; ctx->input[13] = buf_get_le32 (iv + 0); ctx->input[14] = buf_get_le32 (iv + 4); ctx->input[15] = buf_get_le32 (iv + 8); } else if (ivlen == CHACHA20_MIN_IV_SIZE) { + ctx->input[12] = 0; ctx->input[13] = 0; ctx->input[14] = buf_get_le32 (iv + 0); ctx->input[15] = buf_get_le32 (iv + 4); } else { + ctx->input[12] = 0; ctx->input[13] = 0; ctx->input[14] = 0; ctx->input[15] = 0; @@ -402,10 +411,12 @@ chacha20_setiv (void *context, const byte * iv, size_t ivlen) CHACHA20_context_t *ctx = (CHACHA20_context_t *) context; /* draft-nir-cfrg-chacha20-poly1305-02 defines 96-bit and 64-bit nonce. */ - if (iv && ivlen != CHACHA20_MAX_IV_SIZE && ivlen != CHACHA20_MIN_IV_SIZE) + if (iv && ivlen != CHACHA20_MAX_IV_SIZE && ivlen != CHACHA20_MIN_IV_SIZE + && ivlen != CHACHA20_CTR_SIZE) log_info ("WARNING: chacha20_setiv: bad ivlen=%u\n", (u32) ivlen); - if (iv && (ivlen == CHACHA20_MAX_IV_SIZE || ivlen == CHACHA20_MIN_IV_SIZE)) + if (iv && (ivlen == CHACHA20_MAX_IV_SIZE || ivlen == CHACHA20_MIN_IV_SIZE + || ivlen == CHACHA20_CTR_SIZE)) chacha20_ivsetup (ctx, iv, ivlen); else chacha20_ivsetup (ctx, NULL, 0); |