X-Git-Url: https://git.cryptolib.org/?p=avr-crypto-lib.git;a=blobdiff_plain;f=arcfour%2Farcfour.c;fp=arcfour%2Farcfour.c;h=3f155a597e18803d8523e992553f5d93fd6bc41a;hp=ba66c165dd44e89e2d5691b2c3b0414fbe3b1d9f;hb=8d1970350aa1d7cdcb59cf79f7f60e385e2816e5;hpb=a30df60ac814350db243b270034ef188c8d02d5e diff --git a/arcfour/arcfour.c b/arcfour/arcfour.c index ba66c16..3f155a5 100644 --- a/arcfour/arcfour.c +++ b/arcfour/arcfour.c @@ -1,21 +1,21 @@ /* arcfour.c */ /* - This file is part of the AVR-Crypto-Lib. - Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de) + This file is part of the AVR-Crypto-Lib. + Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de) - This program is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. - You should have received a copy of the GNU General Public License - along with this program. If not, see . -*/ + You should have received a copy of the GNU General Public License + along with this program. If not, see . + */ /* * File: arcfour.c * Author: Daniel Otte @@ -33,40 +33,42 @@ * length is length of key in bytes! */ -void arcfour_init(const void *key, uint16_t length_b, arcfour_ctx_t *ctx){ - uint8_t t; - const uint8_t length_B = length_b/8; - uint8_t nidx = length_B; - uint8_t x=0,y=0; - const uint8_t *kptr = (const uint8_t*)key; - do{ - ctx->s[x]=x; - }while((uint8_t)++x); +void arcfour_init(const void *key, uint16_t length_b, arcfour_ctx_t *ctx) +{ + uint8_t t; + const uint8_t length_B = length_b / 8; + uint8_t nidx = length_B; + uint8_t x = 0, y = 0; + const uint8_t *kptr = (const uint8_t*) key; + do { + ctx->s[x] = x; + } while ((uint8_t) ++x); - do{ - y += ctx->s[x] + *kptr++; - if(!--nidx){ - kptr = (const uint8_t*)key; - nidx = length_B; - } - y &= 0xff; - /* ctx->s[y] <--> ctx->s[x] */ - t = ctx->s[y]; - ctx->s[y] = ctx->s[x]; - ctx->s[x] = t; - }while((uint8_t)++x); + do { + y += ctx->s[x] + *kptr++; + if (!--nidx) { + kptr = (const uint8_t*) key; + nidx = length_B; + } + y &= 0xff; + /* ctx->s[y] <--> ctx->s[x] */ + t = ctx->s[y]; + ctx->s[y] = ctx->s[x]; + ctx->s[x] = t; + } while ((uint8_t) ++x); - ctx->i = ctx->j = 0; + ctx->i = ctx->j = 0; } -uint8_t arcfour_gen(arcfour_ctx_t *ctx){ - uint8_t t; - ctx->i++; - ctx->j += ctx->s[ctx->i]; - /* ctx->s[i] <--> ctx->s[j] */ - t = ctx->s[ctx->j]; - ctx->s[ctx->j] = ctx->s[ctx->i]; - ctx->s[ctx->i] = t; - return ctx->s[(ctx->s[ctx->j] + ctx->s[ctx->i]) & 0xff]; +uint8_t arcfour_gen(arcfour_ctx_t *ctx) +{ + uint8_t t; + ctx->i++; + ctx->j += ctx->s[ctx->i]; + /* ctx->s[i] <--> ctx->s[j] */ + t = ctx->s[ctx->j]; + ctx->s[ctx->j] = ctx->s[ctx->i]; + ctx->s[ctx->i] = t; + return ctx->s[(ctx->s[ctx->j] + ctx->s[ctx->i]) & 0xff]; }