--- /dev/null
+/* ====================================================================
+ * Copyright (c) 2011 The OpenSSL Project. 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.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED 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 OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS 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 <openssl/crypto.h>
+#include "modes_lcl.h"
+#include <string.h>
+
+#ifndef MODES_DEBUG
+# ifndef NDEBUG
+# define NDEBUG
+# endif
+#endif
+#include <assert.h>
+
+typedef struct {
+ union { u8 c[16]; size_t s[16/sizeof(size_t)]; } nonce, cmac,
+ scratch, inp;
+ u64 blocks;
+ block128_f block;
+ void *key;
+} CCM128_CONTEXT;
+
+/* First you setup M and L parameters and pass the key schedule */
+void CRYPTO_ccm128_init(CCM128_CONTEXT *ctx,
+ unsigned int M,unsigned int L,void *key)
+{
+ memset(ctx->nonce.c,0,sizeof(ctx->nonce.c));
+ ctx->nonce.c[0] = ((u8)(L-1)&7) | (u8)(((M-2)/2)&7)<<3;
+ ctx->blocks = 0;
+ ctx->key = key;
+}
+
+/* !!! Following interfaces are to be called *once* per packet !!! */
+
+/* Then you setup per-message nonce and pass the length of the message */
+int CRYPTO_ccm128_setiv(CCM128_CONTEXT *ctx,
+ const unsigned char *nonce,size_t nlen,size_t mlen)
+{
+ unsigned int L = ctx->nonce.c[0]&7; /* the L parameter */
+
+ if (nlen<(14-L)) return -1; /* nonce is too short */
+
+ if (sizeof(mlen)==8 && L>=3) {
+ ctx->nonce.c[8] = (u8)(mlen>>(56%(sizeof(mlen)*8)));
+ ctx->nonce.c[9] = (u8)(mlen>>(48%(sizeof(mlen)*8)));
+ ctx->nonce.c[10] = (u8)(mlen>>(40%(sizeof(mlen)*8)));
+ ctx->nonce.c[11] = (u8)(mlen>>(32%(sizeof(mlen)*8)));
+ }
+ else
+ *((size_t *)&ctx->nonce.s[8]) = 0;
+
+ ctx->nonce.c[12] = (u8)(mlen>>24);
+ ctx->nonce.c[13] = (u8)(mlen>>16);
+ ctx->nonce.c[14] = (u8)(mlen>>8);
+ ctx->nonce.c[15] = (u8)mlen;
+
+ ctx->nonce.c[0] &= ~0x40; /* clear Adata flag */
+ memcpy(&ctx->nonce.c[1],nonce,14-L);
+
+ return 0;
+}
+
+/* Then you pass additional authentication data, this is optional */
+void CRYPTO_ccm128_aad(CCM128_CONTEXT *ctx,
+ const unsigned char *aad,size_t alen)
+{ unsigned int i;
+
+ if (alen==0) return;
+
+ ctx->nonce.c[0] |= 0x40; /* set Adata flag */
+ (*ctx->block)(ctx->nonce.c,ctx->cmac.c,ctx->key),
+ ctx->blocks++;
+
+ if (alen<(0x10000-0x100)) {
+ ctx->cmac.c[0] ^= (u8)(alen>>8);
+ ctx->cmac.c[1] ^= (u8)alen;
+ i=2;
+ }
+ else if (sizeof(alen)==8 && alen>=(size_t)1<<32) {
+ ctx->cmac.c[0] ^= 0xFF;
+ ctx->cmac.c[1] ^= 0xFF;
+ ctx->cmac.c[2] ^= (u8)(alen>>(56%(sizeof(alen)*8)));
+ ctx->cmac.c[3] ^= (u8)(alen>>(48%(sizeof(alen)*8)));
+ ctx->cmac.c[4] ^= (u8)(alen>>(40%(sizeof(alen)*8)));
+ ctx->cmac.c[5] ^= (u8)(alen>>(32%(sizeof(alen)*8)));
+ ctx->cmac.c[6] ^= (u8)(alen>>24);
+ ctx->cmac.c[7] ^= (u8)(alen>>16);
+ ctx->cmac.c[8] ^= (u8)(alen>>8);
+ ctx->cmac.c[9] ^= (u8)alen;
+ i=10;
+ }
+ else {
+ ctx->cmac.c[0] ^= 0xFF;
+ ctx->cmac.c[1] ^= 0xFE;
+ ctx->cmac.c[2] ^= (u8)(alen>>24);
+ ctx->cmac.c[3] ^= (u8)(alen>>16);
+ ctx->cmac.c[4] ^= (u8)(alen>>8);
+ ctx->cmac.c[5] ^= (u8)alen;
+ i=6;
+ }
+
+ do {
+ for(;i<16 && alen;++i,++aad,--alen)
+ ctx->cmac.c[i] ^= *aad;
+ (*ctx->block)(ctx->cmac.c,ctx->cmac.c,ctx->key),
+ ctx->blocks++;
+ i=0;
+ } while (alen);
+}
+
+/* Finally you encrypt or decrypt the message */
+
+static void ctr128_inc(unsigned char *counter) {
+ unsigned int n=16;
+ u8 c;
+
+ do {
+ --n;
+ c = counter[n];
+ ++c;
+ counter[n] = c;
+ if (c) return;
+ } while (n);
+}
+
+int CRYPTO_ccm128_encrypt(CCM128_CONTEXT *ctx,
+ const unsigned char *inp, unsigned char *out,
+ size_t len)
+{
+ size_t n;
+ unsigned int i;
+ unsigned char flags = ctx->nonce.c[0];
+
+ if (!(flags&0x40))
+ (*ctx->block)(ctx->nonce.c,ctx->cmac.c,ctx->key),
+ ctx->blocks++;
+
+ flags &= 7; /* extract the L parameter */
+ for (n=0,i=15-flags;i<15;++i) {
+ n |= ctx->nonce.c[i]; ctx->nonce.c[i]=0;
+ n <<= 8;
+ }
+ n |= ctx->nonce.c[15]; /* reconstructed length */
+ ctx->nonce.c[15]=1;
+
+ if (n!=len) return -1; /* length mismatch */
+
+ ctx->blocks += ((len+15)>>3)|1;
+ if (ctx->blocks > (U64(1)<<61)) return -2; /* too much data */
+
+ while (len>=16) {
+#if defined(STRICT_ALIGNMENT)
+ memcpy (ctx->inp.c,inp,16);
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= ctx->inp.s[i];
+#else
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= ((size_t*)inp)[i];
+#endif
+ (*ctx->block)(ctx->cmac.c,ctx->cmac.c,ctx->key);
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ ctr128_inc(ctx->nonce.c);
+#if defined(STRICT_ALIGNMENT)
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->inp.s[i] ^= ctx->scratch.s[i];
+ memcpy(out,ctx->inp.c,16);
+#else
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ((size_t*)out)[i] = ctx->scratch.s[i]^((size_t*)inp)[i];
+#endif
+ inp += 16;
+ out += 16;
+ len -= 16;
+ }
+
+ if (len) {
+ for (i=0; i<len; ++i) ctx->cmac.c[i] ^= inp[i];
+ (*ctx->block)(ctx->cmac.c,ctx->cmac.c,ctx->key);
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ for (i=0; i<len; ++i) out[i] = ctx->scratch.c[i]^inp[i];
+ }
+
+ for (i=15-flags;i<16;++i)
+ ctx->nonce.c[i]=0;
+
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= ctx->scratch.s[i];
+
+ return 0;
+}
+
+int CRYPTO_ccm128_decrypt(CCM128_CONTEXT *ctx,
+ const unsigned char *inp, unsigned char *out,
+ size_t len)
+{
+ size_t n;
+ unsigned int i;
+ unsigned char flags = ctx->nonce.c[0];
+
+ if (!(flags&0x40))
+ (*ctx->block)(ctx->nonce.c,ctx->cmac.c,ctx->key);
+
+ flags &= 7; /* extract the L parameter */
+ for (n=0,i=15-flags;i<15;++i) {
+ n |= ctx->nonce.c[i]; ctx->nonce.c[i]=0;
+ n <<= 8;
+ }
+ n |= ctx->nonce.c[15]; /* reconstructed length */
+ ctx->nonce.c[15]=1;
+
+ if (n!=len) return -1;
+
+ while (len>=16) {
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ ctr128_inc(ctx->nonce.c);
+#if defined(STRICT_ALIGNMENT)
+ memcpy (ctx->inp.c,inp,16);
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= (ctx->scratch.s[i] ^= ctx->inp.s[i]);
+ memcpy (out,ctx->scratch,16);
+#else
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= ((size_t*)out)[i] = ctx->scratch.s[i]^((size_t*)inp)[i];
+#endif
+ (*ctx->block)(ctx->cmac.c,ctx->cmac.c,ctx->key);
+
+ inp += 16;
+ out += 16;
+ len -= 16;
+ }
+
+ if (len) {
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ for (i=0; i<len; ++len)
+ ctx->cmac.c[i] ^= (out[i] = ctx->scratch.c[i]^inp[i]);
+ (*ctx->block)(ctx->cmac.c,ctx->cmac.c,ctx->key);
+ }
+
+ for (i=15-flags;i<16;++i)
+ ctx->nonce.c[i]=0;
+
+ (*ctx->block)(ctx->nonce.c,ctx->scratch.c,ctx->key);
+ for (i=0; i<16/sizeof(size_t); ++i)
+ ctx->cmac.s[i] ^= ctx->scratch.s[i];
+
+ return 0;
+}
+
+size_t CRYPTO_ccm128_tag(CCM128_CONTEXT *ctx,unsigned char *tag,size_t len)
+{ unsigned int M = (ctx->nonce.c[0]>>3)&7; /* the M parameter */
+
+ M *= 2; M += 2;
+ if (len<M) return 0;
+ memcpy(tag,ctx->cmac.c,M);
+ return M;
+}
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