X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fencauth%2Fchachapoly%2Fchacha20poly1305_done.c;fp=libtomcrypt%2Fsrc%2Fencauth%2Fchachapoly%2Fchacha20poly1305_done.c;h=127a7f046f96f48f783c771e4e98f3d524710b1a;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage diff --git a/libtomcrypt/src/encauth/chachapoly/chacha20poly1305_done.c b/libtomcrypt/src/encauth/chachapoly/chacha20poly1305_done.c new file mode 100644 index 0000000..127a7f0 --- /dev/null +++ b/libtomcrypt/src/encauth/chachapoly/chacha20poly1305_done.c @@ -0,0 +1,46 @@ +/* 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. + */ + +#include "tomcrypt.h" + +#ifdef LTC_CHACHA20POLY1305_MODE + +/** + Terminate a ChaCha20Poly1305 stream + @param st The ChaCha20Poly1305 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 chacha20poly1305_done(chacha20poly1305_state *st, unsigned char *tag, unsigned long *taglen) +{ + unsigned char padzero[16] = { 0 }; + unsigned long padlen; + unsigned char buf[16]; + int err; + + LTC_ARGCHK(st != NULL); + + padlen = 16 - (unsigned long)(st->ctlen % 16); + if (padlen < 16) { + if ((err = poly1305_process(&st->poly, padzero, padlen)) != CRYPT_OK) return err; + } + STORE64L(st->aadlen, buf); + STORE64L(st->ctlen, buf + 8); + if ((err = poly1305_process(&st->poly, buf, 16)) != CRYPT_OK) return err; + if ((err = poly1305_done(&st->poly, tag, taglen)) != CRYPT_OK) return err; + if ((err = chacha_done(&st->chacha)) != CRYPT_OK) return err; + return CRYPT_OK; +} + +#endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */