From 03cf7e784caa4c61febbf249be63cbae3e368ac9 Mon Sep 17 00:00:00 2001 From: Andy Polyakov Date: Fri, 6 Jan 2012 13:19:16 +0000 Subject: [PATCH] cmac.c: optimize make_kn and move zero_iv to const segment. --- crypto/cmac/cmac.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/crypto/cmac/cmac.c b/crypto/cmac/cmac.c index 5807e30ddd..064b67d073 100644 --- a/crypto/cmac/cmac.c +++ b/crypto/cmac/cmac.c @@ -77,19 +77,17 @@ struct CMAC_CTX_st /* Make temporary keys K1 and K2 */ -static void make_kn(unsigned char *k1, unsigned char *l, int bl) +static void make_kn(unsigned char *k1, const unsigned char *l, int bl) { int i; + unsigned char c = l[0], carry = c>>7, cnext; + /* Shift block to left, including carry */ - for (i = 0; i < bl; i++) - { - k1[i] = l[i] << 1; - if (i < bl - 1 && l[i + 1] & 0x80) - k1[i] |= 1; - } + for (i = 0; i < bl-1; i++, c = cnext) + k1[i] = (c << 1) | ((cnext=l[i+1]) >> 7); + /* If MSB set fixup with R */ - if (l[0] & 0x80) - k1[bl - 1] ^= bl == 16 ? 0x87 : 0x1b; + k1[i] = (c << 1) ^ ((0-carry)&(bl==16?0x87:0x1b)); } CMAC_CTX *CMAC_CTX_new(void) @@ -143,7 +141,8 @@ int CMAC_CTX_copy(CMAC_CTX *out, const CMAC_CTX *in) int CMAC_Init(CMAC_CTX *ctx, const void *key, size_t keylen, const EVP_CIPHER *cipher, ENGINE *impl) { - static unsigned char zero_iv[EVP_MAX_BLOCK_LENGTH]; + __fips_constseg + static const unsigned char zero_iv[EVP_MAX_BLOCK_LENGTH] = {0}; /* All zeros means restart */ if (!key && !cipher && !impl && keylen == 0) { -- 2.34.1