diff --git a/makefile b/makefile index 6cd433a..a7c376d 100644 --- a/makefile +++ b/makefile @@ -121,6 +121,8 @@ src/ciphers/camellia.o src/ciphers/cast5.o src/ciphers/des.o src/ciphers/kasumi. src/ciphers/kseed.o src/ciphers/multi2.o src/ciphers/noekeon.o src/ciphers/rc2.o src/ciphers/rc5.o \ src/ciphers/rc6.o src/ciphers/safer/safer.o src/ciphers/safer/saferp.o src/ciphers/skipjack.o \ src/ciphers/twofish/twofish.o src/ciphers/xtea.o src/encauth/ccm/ccm_memory.o \ +src/encauth/ccm/ccm_done.o src/encauth/ccm/ccm_process.o src/encauth/ccm/ccm_reset.o \ +src/encauth/ccm/ccm_add_aad.o src/encauth/ccm/ccm_init.o src/encauth/ccm/ccm_add_nonce.o \ src/encauth/ccm/ccm_memory_ex.o src/encauth/ccm/ccm_test.o src/encauth/eax/eax_addheader.o \ src/encauth/eax/eax_decrypt.o src/encauth/eax/eax_decrypt_verify_memory.o src/encauth/eax/eax_done.o \ src/encauth/eax/eax_encrypt_authenticate_memory.o src/encauth/eax/eax_encrypt.o \ diff --git a/src/encauth/ccm/ccm_add_aad.c b/src/encauth/ccm/ccm_add_aad.c new file mode 100644 index 0000000..9b0cf0c --- /dev/null +++ b/src/encauth/ccm/ccm_add_aad.c @@ -0,0 +1,58 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Add AAD to the CCM state + @param ccm The CCM state + @param adata The additional authentication data to add to the CCM state + @param adatalen The length of the AAD data. + @return CRYPT_OK on success + */ +int ccm_add_aad(ccm_state *ccm, + const unsigned char *adata, unsigned long adatalen) +{ + unsigned long y; + int err; + + if (ccm->aadlen < ccm->current_aadlen + adatalen) { + return CRYPT_INVALID_ARG; + } + ccm->current_aadlen += adatalen; + + /* now add the data */ + for (y = 0; y < adatalen; y++) { + if (ccm->x == 16) { + /* full block so let's encrypt it */ + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->PAD, ccm->PAD, &ccm->K)) != CRYPT_OK) { + return CRYPT_ERROR; + } + ccm->x = 0; + } + ccm->PAD[ccm->x++] ^= adata[y]; + } + + /* remainder? */ + if (ccm->aadlen == ccm->current_aadlen) { + if (ccm->x != 0) { + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->PAD, ccm->PAD, &ccm->K)) != CRYPT_OK) { + return CRYPT_ERROR; + } + } + ccm->x = 0; + } + + return CRYPT_OK; +} + +#endif diff --git a/src/encauth/ccm/ccm_add_nonce.c b/src/encauth/ccm/ccm_add_nonce.c new file mode 100644 index 0000000..1cae548 --- /dev/null +++ b/src/encauth/ccm/ccm_add_nonce.c @@ -0,0 +1,108 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Add nonce data to the CCM state + @param ccm The CCM state + @param nonce The nonce data to add + @param noncelen The length of the nonce + @return CRYPT_OK on success + */ +int ccm_add_nonce(ccm_state *ccm, + const unsigned char *nonce, unsigned long noncelen) +{ + unsigned long x, y, len; + int err; + + /* increase L to match the nonce len */ + ccm->noncelen = (noncelen > 13) ? 13 : noncelen; + if ((15 - ccm->noncelen) > ccm->L) { + ccm->L = 15 - ccm->noncelen; + } + + /* decrease noncelen to match L */ + if ((ccm->noncelen + ccm->L) > 15) { + ccm->noncelen = 15 - ccm->L; + } + + /* form B_0 == flags | Nonce N | l(m) */ + x = 0; + ccm->PAD[x++] = (unsigned char)(((ccm->aadlen > 0) ? (1<<6) : 0) | + (((ccm->taglen - 2)>>1)<<3) | + (ccm->L-1)); + + /* nonce */ + for (y = 0; y < (16 - (ccm->L + 1)); y++) { + ccm->PAD[x++] = nonce[y]; + } + + /* store len */ + len = ccm->ptlen; + + /* shift len so the upper bytes of len are the contents of the length */ + for (y = ccm->L; y < 4; y++) { + len <<= 8; + } + + /* store l(m) (only store 32-bits) */ + for (y = 0; ccm->L > 4 && (ccm->L-y)>4; y++) { + ccm->PAD[x++] = 0; + } + for (; y < ccm->L; y++) { + ccm->PAD[x++] = (unsigned char)((len >> 24) & 255); + len <<= 8; + } + + /* encrypt PAD */ + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->PAD, ccm->PAD, &ccm->K)) != CRYPT_OK) { + return err; + } + + /* handle header */ + ccm->x = 0; + if (ccm->aadlen > 0) { + /* store length */ + if (ccm->aadlen < ((1UL<<16) - (1UL<<8))) { + ccm->PAD[ccm->x++] ^= (ccm->aadlen>>8) & 255; + ccm->PAD[ccm->x++] ^= ccm->aadlen & 255; + } else { + ccm->PAD[ccm->x++] ^= 0xFF; + ccm->PAD[ccm->x++] ^= 0xFE; + ccm->PAD[ccm->x++] ^= (ccm->aadlen>>24) & 255; + ccm->PAD[ccm->x++] ^= (ccm->aadlen>>16) & 255; + ccm->PAD[ccm->x++] ^= (ccm->aadlen>>8) & 255; + ccm->PAD[ccm->x++] ^= ccm->aadlen & 255; + } + } + + /* setup the ctr counter */ + x = 0; + + /* flags */ + ccm->ctr[x++] = (unsigned char)ccm->L-1; + + /* nonce */ + for (y = 0; y < (16 - (ccm->L+1)); ++y) { + ccm->ctr[x++] = nonce[y]; + } + /* offset */ + while (x < 16) { + ccm->ctr[x++] = 0; + } + + ccm->CTRlen = 16; + return CRYPT_OK; +} + +#endif diff --git a/src/encauth/ccm/ccm_done.c b/src/encauth/ccm/ccm_done.c new file mode 100644 index 0000000..5ca6a78 --- /dev/null +++ b/src/encauth/ccm/ccm_done.c @@ -0,0 +1,61 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Terminate a CCM stream + @param ccm The CCM state + @param tag [out] The destination for the MAC tag + @param taglen [in/out] The length of the MAC tag + @return CRYPT_OK on success + */ +int ccm_done(ccm_state *ccm, + unsigned char *tag, unsigned long *taglen) +{ + unsigned long x, y; + int err; + + /* Check all data have been processed */ + if (ccm->ptlen != ccm->current_ptlen) { + return CRYPT_ERROR; + } + + LTC_ARGCHK(tag != NULL); + LTC_ARGCHK(taglen != NULL); + + if (ccm->x != 0) { + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->PAD, ccm->PAD, &ccm->K)) != CRYPT_OK) { + return err; + } + } + + /* setup CTR for the TAG (zero the count) */ + for (y = 15; y > 15 - ccm->L; y--) { + ccm->ctr[y] = 0x00; + } + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->ctr, ccm->CTRPAD, &ccm->K)) != CRYPT_OK) { + return err; + } + + cipher_descriptor[ccm->cipher].done(&ccm->K); + + /* store the TAG */ + for (x = 0; x < 16 && x < *taglen; x++) { + tag[x] = ccm->PAD[x] ^ ccm->CTRPAD[x]; + } + *taglen = x; + + return CRYPT_OK; +} + +#endif diff --git a/src/encauth/ccm/ccm_init.c b/src/encauth/ccm/ccm_init.c new file mode 100644 index 0000000..4819bda --- /dev/null +++ b/src/encauth/ccm/ccm_init.c @@ -0,0 +1,78 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Initialize a CCM state + @param ccm The CCM state to initialize + @param cipher The index of the cipher to use + @param key The secret key + @param keylen The length of the secret key + @param ptlen The length of the plain/cipher text that will be processed + @param taglen The max length of the MAC tag + @param aadlen The length of the AAD + + @return CRYPT_OK on success + */ +int ccm_init(ccm_state *ccm, int cipher, + const unsigned char *key, int keylen, int ptlen, int taglen, int aadlen) +{ + int err; + + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(taglen != 0); + + memset(ccm, 0, sizeof(ccm_state)); + + /* check cipher input */ + if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { + return err; + } + if (cipher_descriptor[cipher].block_length != 16) { + return CRYPT_INVALID_CIPHER; + } + + /* make sure the taglen is even and <= 16 */ + ccm->taglen = taglen; + ccm->taglen &= ~1; + if (ccm->taglen > 16) { + ccm->taglen = 16; + } + + /* can't use < 4 */ + if (ccm->taglen < 4) { + return CRYPT_INVALID_ARG; + } + + /* schedule key */ + if ((err = cipher_descriptor[cipher].setup(key, keylen, 0, &ccm->K)) != CRYPT_OK) { + return err; + } + ccm->cipher = cipher; + + /* let's get the L value */ + ccm->ptlen = ptlen; + ccm->L = 0; + while (ptlen) { + ++ccm->L; + ptlen >>= 8; + } + if (ccm->L <= 1) { + ccm->L = 2; + } + + ccm->aadlen = aadlen; + return CRYPT_OK; +} + +#endif diff --git a/src/encauth/ccm/ccm_process.c b/src/encauth/ccm/ccm_process.c new file mode 100644 index 0000000..f784473 --- /dev/null +++ b/src/encauth/ccm/ccm_process.c @@ -0,0 +1,84 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Process plaintext/ciphertext through CCM + @param ccm The CCM state + @param pt The plaintext + @param ptlen The plaintext length (ciphertext length is the same) + @param ct The ciphertext + @param direction Encrypt or Decrypt mode (CCM_ENCRYPT or CCM_DECRYPT) + @return CRYPT_OK on success + */ +int ccm_process(ccm_state *ccm, + unsigned char *pt, unsigned long ptlen, + unsigned char *ct, + int direction) +{ + unsigned char y, z, b; + int err; + + /* Check aad has been correctly added */ + if (ccm->aadlen != ccm->current_aadlen) { + return CRYPT_ERROR; + } + + /* Check we do not process too much data */ + if (ccm->ptlen < ccm->current_ptlen + ptlen) { + return CRYPT_ERROR; + } + ccm->current_ptlen += ptlen; + + /* now handle the PT */ + if (ptlen > 0) { + LTC_ARGCHK(pt != NULL); + LTC_ARGCHK(ct != NULL); + y = 0; + + for (; y < ptlen; y++) { + /* increment the ctr? */ + if (ccm->CTRlen == 16) { + for (z = 15; z > 15-ccm->L; z--) { + ccm->ctr[z] = (ccm->ctr[z] + 1) & 255; + if (ccm->ctr[z]) break; + } + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->ctr, ccm->CTRPAD, &ccm->K)) != CRYPT_OK) { + return err; + } + ccm->CTRlen = 0; + } + + /* if we encrypt we add the bytes to the MAC first */ + if (direction == CCM_ENCRYPT) { + b = pt[y]; + ct[y] = b ^ ccm->CTRPAD[ccm->CTRlen++]; + } else { + b = ct[y] ^ ccm->CTRPAD[ccm->CTRlen++]; + pt[y] = b; + } + + if (ccm->x == 16) { + if ((err = cipher_descriptor[ccm->cipher].ecb_encrypt(ccm->PAD, ccm->PAD, &ccm->K)) != CRYPT_OK) { + return err; + } + ccm->x = 0; + } + ccm->PAD[ccm->x++] ^= b; + } + } + + return CRYPT_OK; +} + +#endif diff --git a/src/encauth/ccm/ccm_reset.c b/src/encauth/ccm/ccm_reset.c new file mode 100644 index 0000000..855789d --- /dev/null +++ b/src/encauth/ccm/ccm_reset.c @@ -0,0 +1,33 @@ +/* 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 + */ +#include "tomcrypt.h" + +#ifdef LTC_CCM_MODE + +/** + Reset a CCM state to as if you just called ccm_init(). This saves the initialization time. + @param ccm The CCM state to reset + @return CRYPT_OK on success +*/ +int ccm_reset(ccm_state *ccm) +{ + LTC_ARGCHK(ccm != NULL); + zeromem(ccm->PAD, sizeof(ccm->PAD)); + zeromem(ccm->ctr, sizeof(ccm->ctr)); + zeromem(ccm->CTRPAD, sizeof(ccm->CTRPAD)); + ccm->CTRlen = 0; + ccm->current_ptlen = 0; + ccm->current_aadlen = 0; + + return CRYPT_OK; +} + +#endif diff --git a/src/headers/tomcrypt_mac.h b/src/headers/tomcrypt_mac.h index 5d71af6..fcee633 100644 --- a/src/headers/tomcrypt_mac.h +++ b/src/headers/tomcrypt_mac.h @@ -259,6 +259,44 @@ void ocb3_int_xor_blocks(unsigned char *out, const unsigned char *block_a, const #define CCM_ENCRYPT 0 #define CCM_DECRYPT 1 +typedef struct { + symmetric_key K; + int cipher, /* which cipher */ + taglen, /* length of the tag */ + x; /* index in PAD */ + + unsigned long L, /* L value */ + ptlen, /* length that will be enc / dec */ + current_ptlen, /* current processed length */ + aadlen, /* length of the aad */ + current_aadlen, /* length of the currently provided add */ + noncelen; /* length of the nonce */ + + unsigned char PAD[16], + ctr[16], + CTRPAD[16], + CTRlen; +} ccm_state; + +int ccm_init(ccm_state *ccm, int cipher, + const unsigned char *key, int keylen, int ptlen, int taglen, int aad_len); + +int ccm_reset(ccm_state *ccm); + +int ccm_add_nonce(ccm_state *ccm, + const unsigned char *nonce, unsigned long noncelen); + +int ccm_add_aad(ccm_state *ccm, + const unsigned char *adata, unsigned long adatalen); + +int ccm_process(ccm_state *ccm, + unsigned char *pt, unsigned long ptlen, + unsigned char *ct, + int direction); + +int ccm_done(ccm_state *ccm, + unsigned char *tag, unsigned long *taglen); + int ccm_memory(int cipher, const unsigned char *key, unsigned long keylen, symmetric_key *uskey,