Mercurial > dropbear
view libtomcrypt/src/encauth/ocb/ocb_done_decrypt.c @ 1294:56aba7dedbea
options for disabling "normal" DH
author | Matt Johnston <matt@ucc.asn.au> |
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date | Mon, 02 May 2016 23:48:16 +0200 |
parents | 0cbe8f6dbf9e |
children | f849a5ca2efc |
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/* 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, [email protected], http://libtomcrypt.com */ /** @file ocb_done_decrypt.c OCB implementation, terminate decryption, by Tom St Denis */ #include "tomcrypt.h" #ifdef OCB_MODE /** Terminate a decrypting OCB state @param ocb The OCB state @param ct The ciphertext (if any) @param ctlen The length of the ciphertext (octets) @param pt [out] The plaintext @param tag The authentication tag (to compare against) @param taglen The length of the authentication tag provided @param stat [out] The result of the tag comparison @return CRYPT_OK if the process was successful regardless if the tag is valid */ int ocb_done_decrypt(ocb_state *ocb, const unsigned char *ct, unsigned long ctlen, unsigned char *pt, const unsigned char *tag, unsigned long taglen, int *stat) { int err; unsigned char *tagbuf; unsigned long tagbuflen; LTC_ARGCHK(ocb != NULL); LTC_ARGCHK(pt != NULL); LTC_ARGCHK(ct != NULL); LTC_ARGCHK(tag != NULL); LTC_ARGCHK(stat != NULL); /* default to failed */ *stat = 0; /* allocate memory */ tagbuf = XMALLOC(MAXBLOCKSIZE); if (tagbuf == NULL) { return CRYPT_MEM; } tagbuflen = MAXBLOCKSIZE; if ((err = s_ocb_done(ocb, ct, ctlen, pt, tagbuf, &tagbuflen, 1)) != CRYPT_OK) { goto LBL_ERR; } if (taglen <= tagbuflen && XMEMCMP(tagbuf, tag, taglen) == 0) { *stat = 1; } err = CRYPT_OK; LBL_ERR: #ifdef LTC_CLEAN_STACK zeromem(tagbuf, MAXBLOCKSIZE); #endif XFREE(tagbuf); return err; } #endif /* $Source: /cvs/libtom/libtomcrypt/src/encauth/ocb/ocb_done_decrypt.c,v $ */ /* $Revision: 1.5 $ */ /* $Date: 2006/11/01 09:28:17 $ */