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authorKarel Miko <miko@dcit.cz>2013-09-23 16:13:43 +0200
committerKarel Miko <miko@dcit.cz>2013-09-23 16:13:43 +0200
commit964d0bfd333827a3434287883f676d97c65b4715 (patch)
tree27ff7d9f05137d918723f0647e3709bc8707d0b6 /src/ltc/encauth/ocb3
parent63ac56b71a27951899de8b1c70a71a14614499f8 (diff)
rename src dirs
Diffstat (limited to 'src/ltc/encauth/ocb3')
-rw-r--r--src/ltc/encauth/ocb3/ocb3_add_aad.c81
-rw-r--r--src/ltc/encauth/ocb3/ocb3_decrypt.c86
-rw-r--r--src/ltc/encauth/ocb3/ocb3_decrypt_last.c105
-rw-r--r--src/ltc/encauth/ocb3/ocb3_decrypt_verify_memory.c112
-rw-r--r--src/ltc/encauth/ocb3/ocb3_done.c92
-rw-r--r--src/ltc/encauth/ocb3/ocb3_encrypt.c86
-rw-r--r--src/ltc/encauth/ocb3/ocb3_encrypt_authenticate_memory.c87
-rw-r--r--src/ltc/encauth/ocb3/ocb3_encrypt_last.c107
-rw-r--r--src/ltc/encauth/ocb3/ocb3_init.c138
-rw-r--r--src/ltc/encauth/ocb3/ocb3_int_aad_add_block.c49
-rw-r--r--src/ltc/encauth/ocb3/ocb3_int_calc_offset_zero.c72
-rw-r--r--src/ltc/encauth/ocb3/ocb3_int_ntz.c41
-rw-r--r--src/ltc/encauth/ocb3/ocb3_int_xor_blocks.c40
13 files changed, 1096 insertions, 0 deletions
diff --git a/src/ltc/encauth/ocb3/ocb3_add_aad.c b/src/ltc/encauth/ocb3/ocb3_add_aad.c
new file mode 100644
index 00000000..46086705
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_add_aad.c
@@ -0,0 +1,81 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_add_aad.c
+ OCB implementation, add AAD data, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Add AAD - additional associated data
+ @param ocb The OCB state
+ @param aad The AAD data
+ @param aadlen The size of AAD data (octets)
+ @return CRYPT_OK if successful
+*/
+int ocb3_add_aad(ocb3_state *ocb, const unsigned char *aad, unsigned long aadlen)
+{
+ int err, x, full_blocks, full_blocks_len, last_block_len;
+ unsigned char *data;
+ unsigned long datalen, l;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(aad != NULL);
+
+ if (aadlen == 0) return CRYPT_OK;
+
+ if (ocb->adata_buffer_bytes > 0) {
+ l = ocb->block_len - ocb->adata_buffer_bytes;
+ if (l > aadlen) l = aadlen;
+ XMEMCPY(ocb->adata_buffer+ocb->adata_buffer_bytes, aad, l);
+ ocb->adata_buffer_bytes += l;
+
+ if (ocb->adata_buffer_bytes == ocb->block_len) {
+ if ((err = ocb3_int_aad_add_block(ocb, ocb->adata_buffer)) != CRYPT_OK) {
+ return err;
+ }
+ ocb->adata_buffer_bytes = 0;
+ }
+
+ data = (unsigned char *)aad + l;
+ datalen = aadlen - l;
+ }
+ else {
+ data = (unsigned char *)aad;
+ datalen = aadlen;
+ }
+
+ if (datalen <= 0) return CRYPT_OK;
+
+ full_blocks = datalen/ocb->block_len;
+ full_blocks_len = full_blocks * ocb->block_len;
+ last_block_len = datalen - full_blocks_len;
+
+ for (x=0; x<full_blocks; x++) {
+ if ((err = ocb3_int_aad_add_block(ocb, data+x*ocb->block_len)) != CRYPT_OK) {
+ return err;
+ }
+ }
+
+ if (last_block_len>0) {
+ XMEMCPY(ocb->adata_buffer, data+full_blocks_len, last_block_len);
+ ocb->adata_buffer_bytes = last_block_len;
+ }
+
+ return CRYPT_OK;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_decrypt.c b/src/ltc/encauth/ocb3/ocb3_decrypt.c
new file mode 100644
index 00000000..24d6ad15
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_decrypt.c
@@ -0,0 +1,86 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_decrypt.c
+ OCB implementation, decrypt data, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Decrypt blocks of ciphertext with OCB
+ @param ocb The OCB state
+ @param ct The ciphertext (length multiple of the block size of the block cipher)
+ @param ctlen The length of the input (octets)
+ @param pt [out] The plaintext (length of ct)
+ @return CRYPT_OK if successful
+*/
+int ocb3_decrypt(ocb3_state *ocb, const unsigned char *ct, unsigned long ctlen, unsigned char *pt)
+{
+ unsigned char tmp[MAXBLOCKSIZE];
+ int err, i, full_blocks;
+ unsigned char *pt_b, *ct_b;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(pt != NULL);
+ LTC_ARGCHK(ct != NULL);
+ if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+ return err;
+ }
+ if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length) {
+ return CRYPT_INVALID_ARG;
+ }
+
+ if (ctlen % ocb->block_len) { /* ctlen has to bu multiple of block_len */
+ return CRYPT_INVALID_ARG;
+ }
+
+ full_blocks = ctlen/ocb->block_len;
+ for(i=0; i<full_blocks; i++) {
+ pt_b = (unsigned char *)pt+i*ocb->block_len;
+ ct_b = (unsigned char *)ct+i*ocb->block_len;
+
+ /* ocb->Offset_current[] = ocb->Offset_current[] ^ Offset_{ntz(block_index)} */
+ ocb3_int_xor_blocks(ocb->Offset_current, ocb->Offset_current, ocb->L_[ocb3_int_ntz(ocb->block_index)], ocb->block_len);
+
+ /* tmp[] = ct[] XOR ocb->Offset_current[] */
+ ocb3_int_xor_blocks(tmp, ct_b, ocb->Offset_current, ocb->block_len);
+
+ /* decrypt */
+ if ((err = cipher_descriptor[ocb->cipher].ecb_decrypt(tmp, tmp, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* pt[] = tmp[] XOR ocb->Offset_current[] */
+ ocb3_int_xor_blocks(pt_b, tmp, ocb->Offset_current, ocb->block_len);
+
+ /* ocb->checksum[] = ocb->checksum[] XOR pt[] */
+ ocb3_int_xor_blocks(ocb->checksum, ocb->checksum, pt_b, ocb->block_len);
+
+ ocb->block_index++;
+ }
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(tmp, sizeof(tmp));
+#endif
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_decrypt_last.c b/src/ltc/encauth/ocb3/ocb3_decrypt_last.c
new file mode 100644
index 00000000..a932d537
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_decrypt_last.c
@@ -0,0 +1,105 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_decrypt_last.c
+ OCB implementation, internal helper, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Finish an OCB (decryption) stream
+ @param ocb The OCB state
+ @param ct The remaining ciphertext
+ @param ctlen The length of the ciphertext (octets)
+ @param pt [out] The output buffer
+ @return CRYPT_OK if successful
+*/
+int ocb3_decrypt_last(ocb3_state *ocb, const unsigned char *ct, unsigned long ctlen, unsigned char *pt)
+{
+ unsigned char iOffset_star[MAXBLOCKSIZE];
+ unsigned char iPad[MAXBLOCKSIZE];
+ int err, x, full_blocks, full_blocks_len, last_block_len;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(ct != NULL);
+ if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ full_blocks = ctlen/ocb->block_len;
+ full_blocks_len = full_blocks * ocb->block_len;
+ last_block_len = ctlen - full_blocks_len;
+
+ /* process full blocks first */
+ if (full_blocks>0) {
+ if ((err = ocb3_decrypt(ocb, ct, full_blocks_len, pt)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+
+ if (last_block_len>0) {
+ /* Offset_* = Offset_m xor L_* */
+ ocb3_int_xor_blocks(iOffset_star, ocb->Offset_current, ocb->L_star, ocb->block_len);
+
+ /* Pad = ENCIPHER(K, Offset_*) */
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(iOffset_star, iPad, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* P_* = C_* xor Pad[1..bitlen(C_*)] */
+ ocb3_int_xor_blocks(pt+full_blocks_len, (unsigned char *)ct+full_blocks_len, iPad, last_block_len);
+
+ /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
+ ocb3_int_xor_blocks(ocb->checksum, ocb->checksum, pt+full_blocks_len, last_block_len);
+ for(x=last_block_len; x<ocb->block_len; x++) {
+ if (x == last_block_len)
+ ocb->checksum[x] ^= 0x80;
+ else
+ ocb->checksum[x] ^= 0x00;
+ }
+
+ /* Tag = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) xor HASH(K,A) */
+ /* at this point we calculate only: Tag_part = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) */
+ for(x=0; x<ocb->block_len; x++) {
+ ocb->tag_part[x] = (ocb->checksum[x] ^ iOffset_star[x]) ^ ocb->L_dollar[x];
+ }
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(ocb->tag_part, ocb->tag_part, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+ else {
+ /* Tag = ENCIPHER(K, Checksum_m xor Offset_m xor L_$) xor HASH(K,A) */
+ /* at this point we calculate only: Tag_part = ENCIPHER(K, Checksum_m xor Offset_m xor L_$) */
+ for(x=0; x<ocb->block_len; x++) {
+ ocb->tag_part[x] = (ocb->checksum[x] ^ ocb->Offset_current[x]) ^ ocb->L_dollar[x];
+ }
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(ocb->tag_part, ocb->tag_part, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(iOffset_star, MAXBLOCKSIZE);
+ zeromem(iPad, MAXBLOCKSIZE);
+#endif
+
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_decrypt_verify_memory.c b/src/ltc/encauth/ocb3/ocb3_decrypt_verify_memory.c
new file mode 100644
index 00000000..ce8fe9ce
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_decrypt_verify_memory.c
@@ -0,0 +1,112 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_decrypt_verify_memory.c
+ OCB implementation, helper to decrypt block of memory, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Decrypt and compare the tag with OCB
+ @param cipher The index of the cipher desired
+ @param key The secret key
+ @param keylen The length of the secret key (octets)
+ @param nonce The session nonce (length of the block size of the block cipher)
+ @param noncelen The length of the nonce (octets)
+ @param adata The AAD - additional associated data
+ @param adatalen The length of AAD (octets)
+ @param ct The ciphertext
+ @param ctlen The length of the ciphertext (octets)
+ @param pt [out] The plaintext
+ @param tag The tag to compare against
+ @param taglen The length of the tag (octets)
+ @param stat [out] The result of the tag comparison (1==valid, 0==invalid)
+ @return CRYPT_OK if successful regardless of the tag comparison
+*/
+int ocb3_decrypt_verify_memory(int cipher,
+ const unsigned char *key, unsigned long keylen,
+ const unsigned char *nonce, unsigned long noncelen,
+ const unsigned char *adata, unsigned long adatalen,
+ const unsigned char *ct, unsigned long ctlen,
+ unsigned char *pt,
+ const unsigned char *tag, unsigned long taglen,
+ int *stat)
+{
+ int err;
+ ocb3_state *ocb;
+ unsigned char *buf;
+ unsigned long buflen;
+
+ LTC_ARGCHK(key != NULL);
+ LTC_ARGCHK(nonce != NULL);
+ LTC_ARGCHK(pt != NULL);
+ LTC_ARGCHK(ct != NULL);
+ LTC_ARGCHK(tag != NULL);
+ LTC_ARGCHK(stat != NULL);
+
+ /* default to zero */
+ *stat = 0;
+
+ /* allocate memory */
+ buf = XMALLOC(taglen);
+ ocb = XMALLOC(sizeof(ocb3_state));
+ if (ocb == NULL || buf == NULL) {
+ if (ocb != NULL) {
+ XFREE(ocb);
+ }
+ if (buf != NULL) {
+ XFREE(buf);
+ }
+ return CRYPT_MEM;
+ }
+
+ if ((err = ocb3_init(ocb, cipher, key, keylen, nonce, noncelen)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ if ((err = ocb3_add_aad(ocb, adata, adatalen)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ if ((err = ocb3_decrypt_last(ocb, ct, ctlen, pt)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ buflen = taglen;
+ if ((err = ocb3_done(ocb, buf, &buflen)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* compare tags */
+ if (buflen >= taglen && XMEMCMP(buf, tag, taglen) == 0) {
+ *stat = 1;
+ }
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(ocb, sizeof(ocb3_state));
+#endif
+
+ XFREE(ocb);
+ XFREE(buf);
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_done.c b/src/ltc/encauth/ocb3/ocb3_done.c
new file mode 100644
index 00000000..4102d9c1
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_done.c
@@ -0,0 +1,92 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_done.c
+ OCB implementation, INTERNAL ONLY helper, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Finish OCB processing and compute the tag
+ @param ocb The OCB state
+ @param tag [out] The destination for the authentication tag
+ @param taglen [in/out] The max size and resulting size of the authentication tag
+ @return CRYPT_OK if successful
+*/
+int ocb3_done(ocb3_state *ocb, unsigned char *tag, unsigned long *taglen)
+{
+ unsigned char tmp[MAXBLOCKSIZE];
+ int err, x;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(tag != NULL);
+ LTC_ARGCHK(taglen != NULL);
+ if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* finalize AAD processing */
+
+ if (ocb->adata_buffer_bytes>0) {
+ /* Offset_* = Offset_m xor L_* */
+ ocb3_int_xor_blocks(ocb->aOffset_current, ocb->aOffset_current, ocb->L_star, ocb->block_len);
+
+ /* CipherInput = (A_* || 1 || zeros(127-bitlen(A_*))) xor Offset_* */
+ ocb3_int_xor_blocks(tmp, ocb->adata_buffer, ocb->aOffset_current, ocb->adata_buffer_bytes);
+ for(x=ocb->adata_buffer_bytes; x<ocb->block_len; x++) {
+ if (x == ocb->adata_buffer_bytes) {
+ tmp[x] = 0x80 ^ ocb->aOffset_current[x];
+ }
+ else {
+ tmp[x] = 0x00 ^ ocb->aOffset_current[x];
+ }
+ }
+
+ /* Sum = Sum_m xor ENCIPHER(K, CipherInput) */
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(tmp, tmp, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ ocb3_int_xor_blocks(ocb->aSum_current, ocb->aSum_current, tmp, ocb->block_len);
+ }
+
+ /* finalize TAG computing */
+
+ /* at this point ocb->aSum_current = HASH(K, A) */
+ /* tag = tag ^ HASH(K, A) */
+ ocb3_int_xor_blocks(tmp, ocb->tag_part, ocb->aSum_current, ocb->block_len);
+
+ /* fix taglen if needed */
+ if ((int)*taglen > ocb->block_len) {
+ *taglen = (unsigned long)ocb->block_len;
+ }
+
+ /* copy tag bytes */
+ for(x=0; x<(int)*taglen; x++) tag[x] = tmp[x];
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(tmp, MAXBLOCKSIZE);
+ zeromem(ocb, sizeof(*ocb));
+#endif
+
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_encrypt.c b/src/ltc/encauth/ocb3/ocb3_encrypt.c
new file mode 100644
index 00000000..14504782
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_encrypt.c
@@ -0,0 +1,86 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_encrypt.c
+ OCB implementation, encrypt data, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Encrypt blocks of data with OCB
+ @param ocb The OCB state
+ @param pt The plaintext (length multiple of the block size of the block cipher)
+ @param ptlen The length of the input (octets)
+ @param ct [out] The ciphertext (same size as the pt)
+ @return CRYPT_OK if successful
+*/
+int ocb3_encrypt(ocb3_state *ocb, const unsigned char *pt, unsigned long ptlen, unsigned char *ct)
+{
+ unsigned char tmp[MAXBLOCKSIZE];
+ int err, i, full_blocks;
+ unsigned char *pt_b, *ct_b;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(pt != NULL);
+ LTC_ARGCHK(ct != NULL);
+ if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+ return err;
+ }
+ if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length) {
+ return CRYPT_INVALID_ARG;
+ }
+
+ if (ptlen % ocb->block_len) { /* ptlen has to bu multiple of block_len */
+ return CRYPT_INVALID_ARG;
+ }
+
+ full_blocks = ptlen/ocb->block_len;
+ for(i=0; i<full_blocks; i++) {
+ pt_b = (unsigned char *)pt+i*ocb->block_len;
+ ct_b = (unsigned char *)ct+i*ocb->block_len;
+
+ /* ocb->Offset_current[] = ocb->Offset_current[] ^ Offset_{ntz(block_index)} */
+ ocb3_int_xor_blocks(ocb->Offset_current, ocb->Offset_current, ocb->L_[ocb3_int_ntz(ocb->block_index)], ocb->block_len);
+
+ /* tmp[] = pt[] XOR ocb->Offset_current[] */
+ ocb3_int_xor_blocks(tmp, pt_b, ocb->Offset_current, ocb->block_len);
+
+ /* encrypt */
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(tmp, tmp, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* ct[] = tmp[] XOR ocb->Offset_current[] */
+ ocb3_int_xor_blocks(ct_b, tmp, ocb->Offset_current, ocb->block_len);
+
+ /* ocb->checksum[] = ocb->checksum[] XOR pt[] */
+ ocb3_int_xor_blocks(ocb->checksum, ocb->checksum, pt_b, ocb->block_len);
+
+ ocb->block_index++;
+ }
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(tmp, sizeof(tmp));
+#endif
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_encrypt_authenticate_memory.c b/src/ltc/encauth/ocb3/ocb3_encrypt_authenticate_memory.c
new file mode 100644
index 00000000..60264a2c
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_encrypt_authenticate_memory.c
@@ -0,0 +1,87 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_encrypt_authenticate_memory.c
+ OCB implementation, encrypt block of memory, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Encrypt and generate an authentication code for a buffer of memory
+ @param cipher The index of the cipher desired
+ @param key The secret key
+ @param keylen The length of the secret key (octets)
+ @param nonce The session nonce (length of the block ciphers block size)
+ @param noncelen The length of the nonce (octets)
+ @param adata The AAD - additional associated data
+ @param adatalen The length of AAD (octets)
+ @param pt The plaintext
+ @param ptlen The length of the plaintext (octets)
+ @param ct [out] The ciphertext
+ @param tag [out] The authentication tag
+ @param taglen [in/out] The max size and resulting size of the authentication tag
+ @return CRYPT_OK if successful
+*/
+int ocb3_encrypt_authenticate_memory(int cipher,
+ const unsigned char *key, unsigned long keylen,
+ const unsigned char *nonce, unsigned long noncelen,
+ const unsigned char *adata, unsigned long adatalen,
+ const unsigned char *pt, unsigned long ptlen,
+ unsigned char *ct,
+ unsigned char *tag, unsigned long *taglen)
+{
+ int err;
+ ocb3_state *ocb;
+
+ LTC_ARGCHK(key != NULL);
+ LTC_ARGCHK(nonce != NULL);
+ LTC_ARGCHK(pt != NULL);
+ LTC_ARGCHK(ct != NULL);
+ LTC_ARGCHK(tag != NULL);
+ LTC_ARGCHK(taglen != NULL);
+
+ /* allocate memory */
+ ocb = XMALLOC(sizeof(ocb3_state));
+ if (ocb == NULL) {
+ return CRYPT_MEM;
+ }
+
+ if ((err = ocb3_init(ocb, cipher, key, keylen, nonce, noncelen)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ if ((err = ocb3_add_aad(ocb, adata, adatalen)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ if ((err = ocb3_encrypt_last(ocb, pt, ptlen, ct)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ err = ocb3_done(ocb, tag, taglen);
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(ocb, sizeof(ocb3_state));
+#endif
+
+ XFREE(ocb);
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_encrypt_last.c b/src/ltc/encauth/ocb3/ocb3_encrypt_last.c
new file mode 100644
index 00000000..b21cfae4
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_encrypt_last.c
@@ -0,0 +1,107 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_encrypt_last.c
+ OCB implementation, internal helper, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Finish an OCB (encryption) stream
+ @param ocb The OCB state
+ @param pt The remaining plaintext
+ @param ptlen The length of the plaintext (octets)
+ @param ct [out] The output buffer
+ @return CRYPT_OK if successful
+*/
+int ocb3_encrypt_last(ocb3_state *ocb, const unsigned char *pt, unsigned long ptlen, unsigned char *ct)
+{
+ unsigned char iOffset_star[MAXBLOCKSIZE];
+ unsigned char iPad[MAXBLOCKSIZE];
+ int err, x, full_blocks, full_blocks_len, last_block_len;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(pt != NULL);
+ if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ full_blocks = ptlen/ocb->block_len;
+ full_blocks_len = full_blocks * ocb->block_len;
+ last_block_len = ptlen - full_blocks_len;
+
+ /* process full blocks first */
+ if (full_blocks>0) {
+ if ((err = ocb3_encrypt(ocb, pt, full_blocks_len, ct)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+
+ /* at this point: m = ocb->block_index (last block index), Offset_m = ocb->Offset_current */
+
+ if (last_block_len>0) {
+ /* Offset_* = Offset_m xor L_* */
+ ocb3_int_xor_blocks(iOffset_star, ocb->Offset_current, ocb->L_star, ocb->block_len);
+
+ /* Pad = ENCIPHER(K, Offset_*) */
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(iOffset_star, iPad, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* C_* = P_* xor Pad[1..bitlen(P_*)] */
+ ocb3_int_xor_blocks(ct+full_blocks_len, pt+full_blocks_len, iPad, last_block_len);
+
+ /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
+ ocb3_int_xor_blocks(ocb->checksum, ocb->checksum, pt+full_blocks_len, last_block_len);
+ for(x=last_block_len; x<ocb->block_len; x++) {
+ if (x == last_block_len)
+ ocb->checksum[x] ^= 0x80;
+ else
+ ocb->checksum[x] ^= 0x00;
+ }
+
+ /* Tag = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) xor HASH(K,A) */
+ /* at this point we calculate only: Tag_part = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) */
+ for(x=0; x<ocb->block_len; x++) {
+ ocb->tag_part[x] = (ocb->checksum[x] ^ iOffset_star[x]) ^ ocb->L_dollar[x];
+ }
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(ocb->tag_part, ocb->tag_part, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+ else {
+ /* Tag = ENCIPHER(K, Checksum_m xor Offset_m xor L_$) xor HASH(K,A) */
+ /* at this point we calculate only: Tag_part = ENCIPHER(K, Checksum_m xor Offset_m xor L_$) */
+ for(x=0; x<ocb->block_len; x++) {
+ ocb->tag_part[x] = (ocb->checksum[x] ^ ocb->Offset_current[x]) ^ ocb->L_dollar[x];
+ }
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(ocb->tag_part, ocb->tag_part, &ocb->key)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ }
+
+ err = CRYPT_OK;
+
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(iOffset_star, MAXBLOCKSIZE);
+ zeromem(iPad, MAXBLOCKSIZE);
+#endif
+
+ return err;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_init.c b/src/ltc/encauth/ocb3/ocb3_init.c
new file mode 100644
index 00000000..926288b7
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_init.c
@@ -0,0 +1,138 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_init.c
+ OCB implementation, initialize state, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+static const struct {
+ int len;
+ unsigned char poly_div[MAXBLOCKSIZE],
+ poly_mul[MAXBLOCKSIZE];
+} polys[] = {
+{
+ 8,
+ { 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0D },
+ { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1B }
+}, {
+ 16,
+ { 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x43 },
+ { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x87 }
+}
+};
+
+/**
+ Initialize an OCB context
+ @param ocb [out] The destination of the OCB state
+ @param cipher The index of the desired cipher
+ @param key The secret key
+ @param keylen The length of the secret key (octets)
+ @param nonce The session nonce
+ @param noncelen The length of the session nonce (octets)
+ @return CRYPT_OK if successful
+*/
+int ocb3_init(ocb3_state *ocb, int cipher,
+ const unsigned char *key, unsigned long keylen,
+ const unsigned char *nonce, unsigned long noncelen)
+{
+ int poly, x, y, m, err;
+ unsigned char *previous, *current;
+
+ LTC_ARGCHK(ocb != NULL);
+ LTC_ARGCHK(key != NULL);
+ LTC_ARGCHK(nonce != NULL);
+
+ /* valid cipher? */
+ if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {
+ return err;
+ }
+ ocb->cipher = cipher;
+
+ /* determine which polys to use */
+ ocb->block_len = cipher_descriptor[cipher].block_length;
+ x = (int)(sizeof(polys)/sizeof(polys[0]));
+ for (poly = 0; poly < x; poly++) {
+ if (polys[poly].len == ocb->block_len) {
+ break;
+ }
+ }
+ if (poly == x) {
+ return CRYPT_INVALID_ARG; /* block_len not found in polys */
+ }
+ if (polys[poly].len != ocb->block_len) {
+ return CRYPT_INVALID_ARG;
+ }
+
+ /* schedule the key */
+ if ((err = cipher_descriptor[cipher].setup(key, keylen, 0, &ocb->key)) != CRYPT_OK) {
+ return err;
+ }
+
+ /* L_* = ENCIPHER(K, zeros(128)) */
+ zeromem(ocb->L_star, ocb->block_len);
+ if ((err = cipher_descriptor[cipher].ecb_encrypt(ocb->L_star, ocb->L_star, &ocb->key)) != CRYPT_OK) {
+ return err;
+ }
+
+ /* compute L_$, L_0, L_1, ... */
+ for (x = -1; x < 32; x++) {
+ if (x == -1) { /* gonna compute: L_$ = double(L_*) */
+ current = ocb->L_dollar;
+ previous = ocb->L_star;
+ }
+ else if (x == 0) { /* gonna compute: L_0 = double(L_$) */
+ current = ocb->L_[0];
+ previous = ocb->L_dollar;
+ }
+ else { /* gonna compute: L_i = double(L_{i-1}) for every integer i > 0 */
+ current = ocb->L_[x];
+ previous = ocb->L_[x-1];
+ }
+ m = previous[0] >> 7;
+ for (y = 0; y < ocb->block_len-1; y++) {
+ current[y] = ((previous[y] << 1) | (previous[y+1] >> 7)) & 255;
+ }
+ current[ocb->block_len-1] = (previous[ocb->block_len-1] << 1) & 255;
+ if (m == 1) {
+ /* current[] = current[] XOR polys[poly].poly_mul[]*/
+ ocb3_int_xor_blocks(current, current, polys[poly].poly_mul, ocb->block_len);
+ }
+ }
+
+ /* initialize ocb->Offset_current = Offset_0 */
+ ocb3_int_calc_offset_zero(ocb, nonce, noncelen);
+
+ /* initialize checksum to all zeros */
+ zeromem(ocb->checksum, ocb->block_len);
+
+ /* set block index */
+ ocb->block_index = 1;
+
+ /* initialize AAD related stuff */
+ ocb->ablock_index = 1;
+ ocb->adata_buffer_bytes = 0;
+ zeromem(ocb->aOffset_current, ocb->block_len);
+ zeromem(ocb->aSum_current, ocb->block_len);
+
+ return CRYPT_OK;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_int_aad_add_block.c b/src/ltc/encauth/ocb3/ocb3_int_aad_add_block.c
new file mode 100644
index 00000000..0b7d8f7a
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_int_aad_add_block.c
@@ -0,0 +1,49 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_int_aad_add_block.c
+ OCB implementation, INTERNALL ONLY helper, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Add one block of AAD data (internal function)
+ @param ocb The OCB state
+ @param aad_block [in] AAD data (block_len size)
+ @return CRYPT_OK if successful
+*/
+int ocb3_int_aad_add_block(ocb3_state *ocb, const unsigned char *aad_block)
+{
+ unsigned char tmp[MAXBLOCKSIZE];
+ int err;
+
+ /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */
+ ocb3_int_xor_blocks(ocb->aOffset_current, ocb->aOffset_current, ocb->L_[ocb3_int_ntz(ocb->ablock_index)], ocb->block_len);
+
+ /* Sum_i = Sum_{i-1} xor ENCIPHER(K, A_i xor Offset_i) */
+ ocb3_int_xor_blocks(tmp, aad_block, ocb->aOffset_current, ocb->block_len);
+ if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(tmp, tmp, &ocb->key)) != CRYPT_OK) {
+ return err;
+ }
+ ocb3_int_xor_blocks(ocb->aSum_current, ocb->aSum_current, tmp, ocb->block_len);
+
+ ocb->ablock_index++;
+
+ return CRYPT_OK;
+}
+
+#endif
+
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_int_calc_offset_zero.c b/src/ltc/encauth/ocb3/ocb3_int_calc_offset_zero.c
new file mode 100644
index 00000000..93b171f4
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_int_calc_offset_zero.c
@@ -0,0 +1,72 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_int_calc_offset_zero.c
+ OCB implementation, INTERNAL ONLY helper, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Sets 'ocb->Offset_current' to 'Offset_0' value (internal function)
+ @param ocb The OCB state
+ @param nonce The session nonce
+ @param noncelen The length of the session nonce (octets)
+*/
+void ocb3_int_calc_offset_zero(ocb3_state *ocb, const unsigned char *nonce, unsigned long noncelen)
+{
+ int x, y, bottom;
+ int idx, shift;
+ unsigned char iNonce[MAXBLOCKSIZE];
+ unsigned char iKtop[MAXBLOCKSIZE];
+ unsigned char iStretch[MAXBLOCKSIZE+8];
+
+ /* Nonce = zeros(127-bitlen(N)) || 1 || N */
+ zeromem(iNonce, sizeof(iNonce));
+ for (x = ocb->block_len-1, y=0; y<(int)noncelen; x--, y++) {
+ iNonce[x] = nonce[noncelen-y-1];
+ }
+ iNonce[x] = 0x01;
+
+ /* bottom = str2num(Nonce[123..128]) */
+ bottom = iNonce[ocb->block_len-1] & 0x3F;
+
+ /* Ktop = ENCIPHER(K, Nonce[1..122] || zeros(6)) */
+ iNonce[ocb->block_len-1] = iNonce[ocb->block_len-1] & 0xC0;
+ if ((cipher_descriptor[ocb->cipher].ecb_encrypt(iNonce, iKtop, &ocb->key)) != CRYPT_OK) {
+ zeromem(ocb->Offset_current, ocb->block_len);
+ return;
+ }
+
+ /* Stretch = Ktop || (Ktop[1..64] xor Ktop[9..72]) */
+ for (x = 0; x < ocb->block_len; x++) {
+ iStretch[x] = iKtop[x];
+ }
+ for (y = 0; y < 8; y++) {
+ iStretch[x+y] = iKtop[y] ^ iKtop[y+1];
+ }
+
+ /* Offset_0 = Stretch[1+bottom..128+bottom] */
+ idx = bottom / 8;
+ shift = (bottom % 8);
+ for (x = 0; x < ocb->block_len; x++) {
+ ocb->Offset_current[x] = iStretch[idx+x] << shift;
+ if (shift > 0) {
+ ocb->Offset_current[x] |= iStretch[idx+x+1] >> (8-shift);
+ }
+ }
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_int_ntz.c b/src/ltc/encauth/ocb3/ocb3_int_ntz.c
new file mode 100644
index 00000000..48239fe7
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_int_ntz.c
@@ -0,0 +1,41 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+
+/**
+ @file ocb3_int_ntz.c
+ OCB implementation, INTERNAL ONLY helper, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Returns the number of leading zero bits [from lsb up] (internal function)
+ @param x The 32-bit value to observe
+ @return The number of bits [from the lsb up] that are zero
+*/
+int ocb3_int_ntz(unsigned long x)
+{
+ int c;
+ x &= 0xFFFFFFFFUL;
+ c = 0;
+ while ((x & 1) == 0) {
+ ++c;
+ x >>= 1;
+ }
+ return c;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
diff --git a/src/ltc/encauth/ocb3/ocb3_int_xor_blocks.c b/src/ltc/encauth/ocb3/ocb3_int_xor_blocks.c
new file mode 100644
index 00000000..92eb293f
--- /dev/null
+++ b/src/ltc/encauth/ocb3/ocb3_int_xor_blocks.c
@@ -0,0 +1,40 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ */
+
+/**
+ @file ocb3_int_xor_blocks.c
+ OCB implementation, INTERNAL ONLY helper, by Karel Miko
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB3_MODE
+
+/**
+ Compute xor for two blocks of bytes 'out = block_a XOR block_b' (internal function)
+ @param out The block of bytes (output)
+ @param block_a The block of bytes (input)
+ @param block_b The block of bytes (input)
+ @param block_len The size of block_a, block_b, out
+*/
+void ocb3_int_xor_blocks(unsigned char *out, const unsigned char *block_a, const unsigned char *block_b, unsigned long block_len)
+{
+ int x;
+ if (out == block_a) {
+ for (x = 0; x < (int)block_len; x++) out[x] ^= block_b[x];
+ }
+ else {
+ for (x = 0; x < (int)block_len; x++) out[x] = block_a[x] ^ block_b[x];
+ }
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */