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-rw-r--r--freebsd/sys/opencrypto/cbc_mac.c267
1 files changed, 267 insertions, 0 deletions
diff --git a/freebsd/sys/opencrypto/cbc_mac.c b/freebsd/sys/opencrypto/cbc_mac.c
new file mode 100644
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--- /dev/null
+++ b/freebsd/sys/opencrypto/cbc_mac.c
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+#include <machine/rtems-bsd-kernel-space.h>
+
+/*
+ * Copyright (c) 2018-2019 iXsystems Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/systm.h>
+#include <sys/param.h>
+#include <sys/endian.h>
+#include <opencrypto/cbc_mac.h>
+#include <opencrypto/xform_auth.h>
+
+/*
+ * Given two CCM_CBC_BLOCK_LEN blocks, xor
+ * them into dst, and then encrypt dst.
+ */
+static void
+xor_and_encrypt(struct aes_cbc_mac_ctx *ctx,
+ const uint8_t *src, uint8_t *dst)
+{
+ const uint64_t *b1;
+ uint64_t *b2;
+ uint64_t temp_block[CCM_CBC_BLOCK_LEN/sizeof(uint64_t)];
+
+ b1 = (const uint64_t*)src;
+ b2 = (uint64_t*)dst;
+
+ for (size_t count = 0;
+ count < CCM_CBC_BLOCK_LEN/sizeof(uint64_t);
+ count++) {
+ temp_block[count] = b1[count] ^ b2[count];
+ }
+ rijndaelEncrypt(ctx->keysched, ctx->rounds, (void*)temp_block, dst);
+}
+
+void
+AES_CBC_MAC_Init(struct aes_cbc_mac_ctx *ctx)
+{
+ bzero(ctx, sizeof(*ctx));
+}
+
+void
+AES_CBC_MAC_Setkey(struct aes_cbc_mac_ctx *ctx, const uint8_t *key, uint16_t klen)
+{
+ ctx->rounds = rijndaelKeySetupEnc(ctx->keysched, key, klen * 8);
+}
+
+/*
+ * This is called to set the nonce, aka IV.
+ * Before this call, the authDataLength and cryptDataLength fields
+ * MUST have been set. Sadly, there's no way to return an error.
+ *
+ * The CBC-MAC algorithm requires that the first block contain the
+ * nonce, as well as information about the sizes and lengths involved.
+ */
+void
+AES_CBC_MAC_Reinit(struct aes_cbc_mac_ctx *ctx, const uint8_t *nonce, uint16_t nonceLen)
+{
+ uint8_t b0[CCM_CBC_BLOCK_LEN];
+ uint8_t *bp = b0, flags = 0;
+ uint8_t L = 0;
+ uint64_t dataLength = ctx->cryptDataLength;
+
+ KASSERT(nonceLen >= 7 && nonceLen <= 13,
+ ("nonceLen must be between 7 and 13 bytes"));
+
+ ctx->nonce = nonce;
+ ctx->nonceLength = nonceLen;
+
+ ctx->authDataCount = 0;
+ ctx->blockIndex = 0;
+ explicit_bzero(ctx->staging_block, sizeof(ctx->staging_block));
+
+ /*
+ * Need to determine the L field value. This is the number of
+ * bytes needed to specify the length of the message; the length
+ * is whatever is left in the 16 bytes after specifying flags and
+ * the nonce.
+ */
+ L = 15 - nonceLen;
+
+ flags = ((ctx->authDataLength > 0) << 6) +
+ (((AES_CBC_MAC_HASH_LEN - 2) / 2) << 3) +
+ L - 1;
+ /*
+ * Now we need to set up the first block, which has flags, nonce,
+ * and the message length.
+ */
+ b0[0] = flags;
+ bcopy(nonce, b0 + 1, nonceLen);
+ bp = b0 + 1 + nonceLen;
+
+ /* Need to copy L' [aka L-1] bytes of cryptDataLength */
+ for (uint8_t *dst = b0 + sizeof(b0) - 1; dst >= bp; dst--) {
+ *dst = dataLength;
+ dataLength >>= 8;
+ }
+ /* Now need to encrypt b0 */
+ rijndaelEncrypt(ctx->keysched, ctx->rounds, b0, ctx->block);
+ /* If there is auth data, we need to set up the staging block */
+ if (ctx->authDataLength) {
+ size_t addLength;
+ if (ctx->authDataLength < ((1<<16) - (1<<8))) {
+ uint16_t sizeVal = htobe16(ctx->authDataLength);
+ bcopy(&sizeVal, ctx->staging_block, sizeof(sizeVal));
+ addLength = sizeof(sizeVal);
+ } else if (ctx->authDataLength < (1ULL<<32)) {
+ uint32_t sizeVal = htobe32(ctx->authDataLength);
+ ctx->staging_block[0] = 0xff;
+ ctx->staging_block[1] = 0xfe;
+ bcopy(&sizeVal, ctx->staging_block+2, sizeof(sizeVal));
+ addLength = 2 + sizeof(sizeVal);
+ } else {
+ uint64_t sizeVal = htobe64(ctx->authDataLength);
+ ctx->staging_block[0] = 0xff;
+ ctx->staging_block[1] = 0xff;
+ bcopy(&sizeVal, ctx->staging_block+2, sizeof(sizeVal));
+ addLength = 2 + sizeof(sizeVal);
+ }
+ ctx->blockIndex = addLength;
+ /*
+ * The length descriptor goes into the AAD buffer, so we
+ * need to account for it.
+ */
+ ctx->authDataLength += addLength;
+ ctx->authDataCount = addLength;
+ }
+}
+
+int
+AES_CBC_MAC_Update(struct aes_cbc_mac_ctx *ctx, const uint8_t *data,
+ uint16_t length)
+{
+ size_t copy_amt;
+
+ /*
+ * This will be called in one of two phases:
+ * (1) Applying authentication data, or
+ * (2) Applying the payload data.
+ *
+ * Because CBC-MAC puts the authentication data size before the
+ * data, subsequent calls won't be block-size-aligned. Which
+ * complicates things a fair bit.
+ *
+ * The payload data doesn't have that problem.
+ */
+
+ if (ctx->authDataCount < ctx->authDataLength) {
+ /*
+ * We need to process data as authentication data.
+ * Since we may be out of sync, we may also need
+ * to pad out the staging block.
+ */
+ const uint8_t *ptr = data;
+ while (length > 0) {
+
+ copy_amt = MIN(length,
+ sizeof(ctx->staging_block) - ctx->blockIndex);
+
+ bcopy(ptr, ctx->staging_block + ctx->blockIndex,
+ copy_amt);
+ ptr += copy_amt;
+ length -= copy_amt;
+ ctx->authDataCount += copy_amt;
+ ctx->blockIndex += copy_amt;
+ ctx->blockIndex %= sizeof(ctx->staging_block);
+
+ if (ctx->blockIndex == 0 ||
+ ctx->authDataCount == ctx->authDataLength) {
+ /*
+ * We're done with this block, so we
+ * xor staging_block with block, and then
+ * encrypt it.
+ */
+ xor_and_encrypt(ctx, ctx->staging_block, ctx->block);
+ bzero(ctx->staging_block, sizeof(ctx->staging_block));
+ ctx->blockIndex = 0;
+ if (ctx->authDataCount >= ctx->authDataLength)
+ break;
+ }
+ }
+ /*
+ * We'd like to be able to check length == 0 and return
+ * here, but the way OCF calls us, length is always
+ * blksize (16, in this case). So we have to count on
+ * the fact that OCF calls us separately for the AAD and
+ * for the real data.
+ */
+ return (0);
+ }
+ /*
+ * If we're here, then we're encoding payload data.
+ * This is marginally easier, except that _Update can
+ * be called with non-aligned update lengths. As a result,
+ * we still need to use the staging block.
+ */
+ KASSERT((length + ctx->cryptDataCount) <= ctx->cryptDataLength,
+ ("More encryption data than allowed"));
+
+ while (length) {
+ uint8_t *ptr;
+
+ copy_amt = MIN(sizeof(ctx->staging_block) - ctx->blockIndex,
+ length);
+ ptr = ctx->staging_block + ctx->blockIndex;
+ bcopy(data, ptr, copy_amt);
+ data += copy_amt;
+ ctx->blockIndex += copy_amt;
+ ctx->cryptDataCount += copy_amt;
+ length -= copy_amt;
+ if (ctx->blockIndex == sizeof(ctx->staging_block)) {
+ /* We've got a full block */
+ xor_and_encrypt(ctx, ctx->staging_block, ctx->block);
+ ctx->blockIndex = 0;
+ bzero(ctx->staging_block, sizeof(ctx->staging_block));
+ }
+ }
+ return (0);
+}
+
+void
+AES_CBC_MAC_Final(uint8_t *buf, struct aes_cbc_mac_ctx *ctx)
+{
+ uint8_t s0[CCM_CBC_BLOCK_LEN];
+
+ /*
+ * We first need to check to see if we've got any data
+ * left over to encrypt.
+ */
+ if (ctx->blockIndex != 0) {
+ xor_and_encrypt(ctx, ctx->staging_block, ctx->block);
+ ctx->cryptDataCount += ctx->blockIndex;
+ ctx->blockIndex = 0;
+ explicit_bzero(ctx->staging_block, sizeof(ctx->staging_block));
+ }
+ bzero(s0, sizeof(s0));
+ s0[0] = (15 - ctx->nonceLength) - 1;
+ bcopy(ctx->nonce, s0 + 1, ctx->nonceLength);
+ rijndaelEncrypt(ctx->keysched, ctx->rounds, s0, s0);
+ for (size_t indx = 0; indx < AES_CBC_MAC_HASH_LEN; indx++)
+ buf[indx] = ctx->block[indx] ^ s0[indx];
+ explicit_bzero(s0, sizeof(s0));
+}