X-Git-Url: https://pd.if.org/git/?p=zpackage;a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fencauth%2Focb%2Fs_ocb_done.c;fp=libtomcrypt%2Fsrc%2Fencauth%2Focb%2Fs_ocb_done.c;h=0000000000000000000000000000000000000000;hp=e0501ede2c86315065532dc6776fe0a5105d294a;hb=a670d5d3211446a123f1af646c867ee4aabadc49;hpb=72b60d5f77676b6b500d58bae81a27923fa1bee7 diff --git a/libtomcrypt/src/encauth/ocb/s_ocb_done.c b/libtomcrypt/src/encauth/ocb/s_ocb_done.c deleted file mode 100644 index e0501ed..0000000 --- a/libtomcrypt/src/encauth/ocb/s_ocb_done.c +++ /dev/null @@ -1,146 +0,0 @@ -/* 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 s_ocb_done.c - OCB implementation, internal helper, by Tom St Denis -*/ -#include "tomcrypt.h" - -#ifdef LTC_OCB_MODE - -/* Since the last block is encrypted in CTR mode the same code can - * be used to finish a decrypt or encrypt stream. The only difference - * is we XOR the final ciphertext into the checksum so we have to xor it - * before we CTR [decrypt] or after [encrypt] - * - * the names pt/ptlen/ct really just mean in/inlen/out but this is the way I wrote it... - */ - -/** - Shared code to finish an OCB stream - @param ocb The OCB state - @param pt The remaining plaintext [or input] - @param ptlen The length of the input (octets) - @param ct [out] The output buffer - @param tag [out] The destination for the authentication tag - @param taglen [in/out] The max size and resulting size of the authentication tag - @param mode The mode we are terminating, 0==encrypt, 1==decrypt - @return CRYPT_OK if successful -*/ -int s_ocb_done(ocb_state *ocb, const unsigned char *pt, unsigned long ptlen, - unsigned char *ct, unsigned char *tag, unsigned long *taglen, int mode) - -{ - unsigned char *Z, *Y, *X; - int err, x; - - LTC_ARGCHK(ocb != NULL); - LTC_ARGCHK(pt != NULL); - LTC_ARGCHK(ct != NULL); - LTC_ARGCHK(tag != NULL); - LTC_ARGCHK(taglen != NULL); - if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) { - return err; - } - if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length || - (int)ptlen > ocb->block_len || (int)ptlen < 0) { - return CRYPT_INVALID_ARG; - } - - /* allocate ram */ - Z = XMALLOC(MAXBLOCKSIZE); - Y = XMALLOC(MAXBLOCKSIZE); - X = XMALLOC(MAXBLOCKSIZE); - if (X == NULL || Y == NULL || Z == NULL) { - if (X != NULL) { - XFREE(X); - } - if (Y != NULL) { - XFREE(Y); - } - if (Z != NULL) { - XFREE(Z); - } - return CRYPT_MEM; - } - - /* compute X[m] = len(pt[m]) XOR Lr XOR Z[m] */ - ocb_shift_xor(ocb, X); - XMEMCPY(Z, X, ocb->block_len); - - X[ocb->block_len-1] ^= (ptlen*8)&255; - X[ocb->block_len-2] ^= ((ptlen*8)>>8)&255; - for (x = 0; x < ocb->block_len; x++) { - X[x] ^= ocb->Lr[x]; - } - - /* Y[m] = E(X[m])) */ - if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(X, Y, &ocb->key)) != CRYPT_OK) { - goto error; - } - - if (mode == 1) { - /* decrypt mode, so let's xor it first */ - /* xor C[m] into checksum */ - for (x = 0; x < (int)ptlen; x++) { - ocb->checksum[x] ^= ct[x]; - } - } - - /* C[m] = P[m] xor Y[m] */ - for (x = 0; x < (int)ptlen; x++) { - ct[x] = pt[x] ^ Y[x]; - } - - if (mode == 0) { - /* encrypt mode */ - /* xor C[m] into checksum */ - for (x = 0; x < (int)ptlen; x++) { - ocb->checksum[x] ^= ct[x]; - } - } - - /* xor Y[m] and Z[m] into checksum */ - for (x = 0; x < ocb->block_len; x++) { - ocb->checksum[x] ^= Y[x] ^ Z[x]; - } - - /* encrypt checksum, er... tag!! */ - if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(ocb->checksum, X, &ocb->key)) != CRYPT_OK) { - goto error; - } - cipher_descriptor[ocb->cipher].done(&ocb->key); - - /* now store it */ - for (x = 0; x < ocb->block_len && x < (int)*taglen; x++) { - tag[x] = X[x]; - } - *taglen = x; - -#ifdef LTC_CLEAN_STACK - zeromem(X, MAXBLOCKSIZE); - zeromem(Y, MAXBLOCKSIZE); - zeromem(Z, MAXBLOCKSIZE); - zeromem(ocb, sizeof(*ocb)); -#endif -error: - XFREE(X); - XFREE(Y); - XFREE(Z); - - return err; -} - -#endif - - -/* ref: $Format:%D$ */ -/* git commit: $Format:%H$ */ -/* commit time: $Format:%ai$ */