зеркало из https://github.com/mozilla/pjs.git
647 строки
20 KiB
C
647 строки
20 KiB
C
/* arcfour.c - the arc four algorithm.
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*
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* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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*
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* License.
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*
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* The Original Code is the Netscape security libraries.
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*
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* The Initial Developer of the Original Code is
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* Netscape Communications Corporation.
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* Portions created by the Initial Developer are Copyright (C) 1994-2000
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* the Initial Developer. All Rights Reserved.
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*
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* Contributor(s):
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*
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* Alternatively, the contents of this file may be used under the terms of
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* either the GNU General Public License Version 2 or later (the "GPL"), or
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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*
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* ***** END LICENSE BLOCK ***** */
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/* See NOTES ON UMRs, Unititialized Memory Reads, below. */
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#ifdef FREEBL_NO_DEPEND
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#include "stubs.h"
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#endif
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#include "prerr.h"
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#include "secerr.h"
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#include "prtypes.h"
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#include "blapi.h"
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/* Architecture-dependent defines */
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#if defined(SOLARIS) || defined(HPUX) || defined(i386) || defined(IRIX) || \
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defined(_WIN64)
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/* Convert the byte-stream to a word-stream */
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#define CONVERT_TO_WORDS
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#endif
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#if defined(AIX) || defined(OSF1) || defined(NSS_BEVAND_ARCFOUR)
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/* Treat array variables as words, not bytes, on CPUs that take
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* much longer to write bytes than to write words, or when using
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* assembler code that required it.
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*/
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#define USE_WORD
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#endif
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#if defined(_WIN32_WCE)
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#undef WORD
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#define WORD ARC4WORD
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#endif
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#if (defined(IS_64))
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typedef PRUint64 WORD;
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#else
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typedef PRUint32 WORD;
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#endif
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#define WORDSIZE sizeof(WORD)
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#if defined(USE_WORD)
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typedef WORD Stype;
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#else
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typedef PRUint8 Stype;
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#endif
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#define ARCFOUR_STATE_SIZE 256
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#define MASK1BYTE (WORD)(0xff)
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#define SWAP(a, b) \
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tmp = a; \
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a = b; \
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b = tmp;
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/*
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* State information for stream cipher.
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*/
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struct RC4ContextStr
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{
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#if defined(NSS_ARCFOUR_IJ_B4_S) || defined(NSS_BEVAND_ARCFOUR)
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Stype i;
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Stype j;
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Stype S[ARCFOUR_STATE_SIZE];
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#else
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Stype S[ARCFOUR_STATE_SIZE];
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Stype i;
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Stype j;
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#endif
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};
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/*
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* array indices [0..255] to initialize cx->S array (faster than loop).
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*/
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static const Stype Kinit[256] = {
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0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
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0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
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0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
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0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
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0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
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0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
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0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
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0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
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0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
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0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
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0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
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0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
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0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
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0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
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0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
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0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
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0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
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0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
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0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
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0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
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0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
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0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
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0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
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0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
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0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
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0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
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0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
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0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
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0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
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0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
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0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
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0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
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};
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RC4Context *
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RC4_AllocateContext(void)
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{
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return PORT_ZNew(RC4Context);
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}
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SECStatus
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RC4_InitContext(RC4Context *cx, const unsigned char *key, unsigned int len,
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const unsigned char * unused1, int unused2,
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unsigned int unused3, unsigned int unused4)
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{
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int i;
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PRUint8 j, tmp;
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PRUint8 K[256];
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PRUint8 *L;
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/* verify the key length. */
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PORT_Assert(len > 0 && len < ARCFOUR_STATE_SIZE);
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if (len < 0 || len >= ARCFOUR_STATE_SIZE) {
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PORT_SetError(SEC_ERROR_INVALID_ARGS);
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return SECFailure;
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}
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if (cx == NULL) {
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PORT_SetError(SEC_ERROR_INVALID_ARGS);
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return SECFailure;
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}
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/* Initialize the state using array indices. */
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memcpy(cx->S, Kinit, sizeof cx->S);
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/* Fill in K repeatedly with values from key. */
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L = K;
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for (i = sizeof K; i > len; i-= len) {
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memcpy(L, key, len);
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L += len;
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}
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memcpy(L, key, i);
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/* Stir the state of the generator. At this point it is assumed
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* that the key is the size of the state buffer. If this is not
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* the case, the key bytes are repeated to fill the buffer.
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*/
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j = 0;
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#define ARCFOUR_STATE_STIR(ii) \
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j = j + cx->S[ii] + K[ii]; \
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SWAP(cx->S[ii], cx->S[j]);
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for (i=0; i<ARCFOUR_STATE_SIZE; i++) {
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ARCFOUR_STATE_STIR(i);
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}
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cx->i = 0;
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cx->j = 0;
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return SECSuccess;
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}
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/*
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* Initialize a new generator.
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*/
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RC4Context *
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RC4_CreateContext(const unsigned char *key, int len)
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{
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RC4Context *cx = RC4_AllocateContext();
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if (cx) {
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SECStatus rv = RC4_InitContext(cx, key, len, NULL, 0, 0, 0);
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if (rv != SECSuccess) {
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PORT_ZFree(cx, sizeof(*cx));
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cx = NULL;
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}
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}
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return cx;
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}
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void
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RC4_DestroyContext(RC4Context *cx, PRBool freeit)
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{
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if (freeit)
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PORT_ZFree(cx, sizeof(*cx));
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}
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#if defined(NSS_BEVAND_ARCFOUR)
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extern void ARCFOUR(RC4Context *cx, WORD inputLen,
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const unsigned char *input, unsigned char *output);
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#else
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/*
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* Generate the next byte in the stream.
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*/
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#define ARCFOUR_NEXT_BYTE() \
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tmpSi = cx->S[++tmpi]; \
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tmpj += tmpSi; \
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tmpSj = cx->S[tmpj]; \
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cx->S[tmpi] = tmpSj; \
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cx->S[tmpj] = tmpSi; \
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t = tmpSi + tmpSj;
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#ifdef CONVERT_TO_WORDS
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/*
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* Straight ARCFOUR op. No optimization.
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*/
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static SECStatus
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rc4_no_opt(RC4Context *cx, unsigned char *output,
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unsigned int *outputLen, unsigned int maxOutputLen,
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const unsigned char *input, unsigned int inputLen)
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{
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PRUint8 t;
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Stype tmpSi, tmpSj;
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register PRUint8 tmpi = cx->i;
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register PRUint8 tmpj = cx->j;
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unsigned int index;
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PORT_Assert(maxOutputLen >= inputLen);
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if (maxOutputLen < inputLen) {
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PORT_SetError(SEC_ERROR_INVALID_ARGS);
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return SECFailure;
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}
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for (index=0; index < inputLen; index++) {
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/* Generate next byte from stream. */
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ARCFOUR_NEXT_BYTE();
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/* output = next stream byte XOR next input byte */
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output[index] = cx->S[t] ^ input[index];
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}
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*outputLen = inputLen;
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cx->i = tmpi;
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cx->j = tmpj;
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return SECSuccess;
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}
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#else
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/* !CONVERT_TO_WORDS */
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/*
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* Byte-at-a-time ARCFOUR, unrolling the loop into 8 pieces.
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*/
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static SECStatus
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rc4_unrolled(RC4Context *cx, unsigned char *output,
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unsigned int *outputLen, unsigned int maxOutputLen,
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const unsigned char *input, unsigned int inputLen)
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{
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PRUint8 t;
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Stype tmpSi, tmpSj;
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register PRUint8 tmpi = cx->i;
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register PRUint8 tmpj = cx->j;
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int index;
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PORT_Assert(maxOutputLen >= inputLen);
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if (maxOutputLen < inputLen) {
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PORT_SetError(SEC_ERROR_INVALID_ARGS);
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return SECFailure;
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}
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for (index = inputLen / 8; index-- > 0; input += 8, output += 8) {
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ARCFOUR_NEXT_BYTE();
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output[0] = cx->S[t] ^ input[0];
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ARCFOUR_NEXT_BYTE();
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output[1] = cx->S[t] ^ input[1];
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ARCFOUR_NEXT_BYTE();
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output[2] = cx->S[t] ^ input[2];
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ARCFOUR_NEXT_BYTE();
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output[3] = cx->S[t] ^ input[3];
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ARCFOUR_NEXT_BYTE();
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output[4] = cx->S[t] ^ input[4];
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ARCFOUR_NEXT_BYTE();
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output[5] = cx->S[t] ^ input[5];
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ARCFOUR_NEXT_BYTE();
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output[6] = cx->S[t] ^ input[6];
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ARCFOUR_NEXT_BYTE();
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output[7] = cx->S[t] ^ input[7];
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}
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index = inputLen % 8;
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if (index) {
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input += index;
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output += index;
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switch (index) {
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case 7:
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ARCFOUR_NEXT_BYTE();
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output[-7] = cx->S[t] ^ input[-7]; /* FALLTHRU */
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case 6:
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ARCFOUR_NEXT_BYTE();
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output[-6] = cx->S[t] ^ input[-6]; /* FALLTHRU */
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case 5:
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ARCFOUR_NEXT_BYTE();
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output[-5] = cx->S[t] ^ input[-5]; /* FALLTHRU */
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case 4:
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ARCFOUR_NEXT_BYTE();
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output[-4] = cx->S[t] ^ input[-4]; /* FALLTHRU */
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case 3:
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ARCFOUR_NEXT_BYTE();
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output[-3] = cx->S[t] ^ input[-3]; /* FALLTHRU */
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case 2:
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ARCFOUR_NEXT_BYTE();
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output[-2] = cx->S[t] ^ input[-2]; /* FALLTHRU */
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case 1:
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ARCFOUR_NEXT_BYTE();
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output[-1] = cx->S[t] ^ input[-1]; /* FALLTHRU */
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default:
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/* FALLTHRU */
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; /* hp-ux build breaks without this */
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}
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}
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cx->i = tmpi;
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cx->j = tmpj;
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*outputLen = inputLen;
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return SECSuccess;
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}
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#endif
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#ifdef IS_LITTLE_ENDIAN
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#define ARCFOUR_NEXT4BYTES_L(n) \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n ); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 8); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 16); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 24);
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#else
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#define ARCFOUR_NEXT4BYTES_B(n) \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 24); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 16); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n + 8); \
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ARCFOUR_NEXT_BYTE(); streamWord |= (WORD)cx->S[t] << (n );
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#endif
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#if (defined(IS_64) && !defined(__sparc)) || defined(NSS_USE_64)
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/* 64-bit wordsize */
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#ifdef IS_LITTLE_ENDIAN
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#define ARCFOUR_NEXT_WORD() \
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{ streamWord = 0; ARCFOUR_NEXT4BYTES_L(0); ARCFOUR_NEXT4BYTES_L(32); }
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#else
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#define ARCFOUR_NEXT_WORD() \
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{ streamWord = 0; ARCFOUR_NEXT4BYTES_B(32); ARCFOUR_NEXT4BYTES_B(0); }
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#endif
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#else
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/* 32-bit wordsize */
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#ifdef IS_LITTLE_ENDIAN
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#define ARCFOUR_NEXT_WORD() \
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{ streamWord = 0; ARCFOUR_NEXT4BYTES_L(0); }
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#else
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#define ARCFOUR_NEXT_WORD() \
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{ streamWord = 0; ARCFOUR_NEXT4BYTES_B(0); }
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#endif
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#endif
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#ifdef IS_LITTLE_ENDIAN
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#define RSH <<
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#define LSH >>
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#else
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#define RSH >>
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#define LSH <<
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#endif
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#ifdef CONVERT_TO_WORDS
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/* NOTE about UMRs, Uninitialized Memory Reads.
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*
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* This code reads all input data a WORD at a time, rather than byte at
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* a time, and writes all output data a WORD at a time. Shifting and
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* masking is used to remove unwanted data and realign bytes when
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* needed. The first and last words of output are read, modified, and
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* written when needed to preserve any unchanged bytes. This is a huge
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* win on machines with high memory latency.
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*
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* However, when the input and output buffers do not begin and end on WORD
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* boundaries, and the WORDS in memory that contain the first and last
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* bytes of those buffers contain uninitialized data, then this code will
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* read those uninitialized bytes, causing a UMR error to be reported by
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* some tools.
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*
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* These UMRs are NOT a problem, NOT errors, and do NOT need to be "fixed".
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*
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* All the words read and written contain at least one byte that is
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* part of the input data or output data. No words are read or written
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* that do not contain data that is part of the buffer. Therefore,
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* these UMRs cannot cause page faults or other problems unless the
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* buffers have been assigned to improper addresses that would cause
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* page faults with or without UMRs.
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*/
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static SECStatus
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rc4_wordconv(RC4Context *cx, unsigned char *output,
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unsigned int *outputLen, unsigned int maxOutputLen,
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const unsigned char *input, unsigned int inputLen)
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{
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ptrdiff_t inOffset = (ptrdiff_t)input % WORDSIZE;
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ptrdiff_t outOffset = (ptrdiff_t)output % WORDSIZE;
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register WORD streamWord, mask;
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register WORD *pInWord, *pOutWord;
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register WORD inWord, nextInWord;
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PRUint8 t;
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register Stype tmpSi, tmpSj;
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register PRUint8 tmpi = cx->i;
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register PRUint8 tmpj = cx->j;
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unsigned int byteCount;
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unsigned int bufShift, invBufShift;
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int i;
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PORT_Assert(maxOutputLen >= inputLen);
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if (maxOutputLen < inputLen) {
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PORT_SetError(SEC_ERROR_INVALID_ARGS);
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return SECFailure;
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}
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if (inputLen < 2*WORDSIZE) {
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/* Ignore word conversion, do byte-at-a-time */
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return rc4_no_opt(cx, output, outputLen, maxOutputLen, input, inputLen);
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}
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*outputLen = inputLen;
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pInWord = (WORD *)(input - inOffset);
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if (inOffset < outOffset) {
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bufShift = 8*(outOffset - inOffset);
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invBufShift = 8*WORDSIZE - bufShift;
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} else {
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invBufShift = 8*(inOffset - outOffset);
|
|
bufShift = 8*WORDSIZE - invBufShift;
|
|
}
|
|
/*****************************************************************/
|
|
/* Step 1: */
|
|
/* If the first output word is partial, consume the bytes in the */
|
|
/* first partial output word by loading one or two words of */
|
|
/* input and shifting them accordingly. Otherwise, just load */
|
|
/* in the first word of input. At the end of this block, at */
|
|
/* least one partial word of input should ALWAYS be loaded. */
|
|
/*****************************************************************/
|
|
if (outOffset) {
|
|
/* Generate input and stream words aligned relative to the
|
|
* partial output buffer.
|
|
*/
|
|
byteCount = WORDSIZE - outOffset;
|
|
pOutWord = (WORD *)(output - outOffset);
|
|
mask = streamWord = 0;
|
|
#ifdef IS_LITTLE_ENDIAN
|
|
for (i = WORDSIZE - byteCount; i < WORDSIZE; i++) {
|
|
#else
|
|
for (i = byteCount - 1; i >= 0; --i) {
|
|
#endif
|
|
ARCFOUR_NEXT_BYTE();
|
|
streamWord |= (WORD)(cx->S[t]) << 8*i;
|
|
mask |= MASK1BYTE << 8*i;
|
|
} /* } */
|
|
inWord = *pInWord++; /* UMR? see comments above. */
|
|
/* If buffers are relatively misaligned, shift the bytes in inWord
|
|
* to be aligned to the output buffer.
|
|
*/
|
|
nextInWord = 0;
|
|
if (inOffset < outOffset) {
|
|
/* Have more bytes than needed, shift remainder into nextInWord */
|
|
nextInWord = inWord LSH 8*(inOffset + byteCount);
|
|
inWord = inWord RSH bufShift;
|
|
} else if (inOffset > outOffset) {
|
|
/* Didn't get enough bytes from current input word, load another
|
|
* word and then shift remainder into nextInWord.
|
|
*/
|
|
nextInWord = *pInWord++;
|
|
inWord = (inWord LSH invBufShift) |
|
|
(nextInWord RSH bufShift);
|
|
nextInWord = nextInWord LSH invBufShift;
|
|
}
|
|
/* Store output of first partial word */
|
|
*pOutWord = (*pOutWord & ~mask) | ((inWord ^ streamWord) & mask);
|
|
/* UMR? See comments above. */
|
|
|
|
/* Consumed byteCount bytes of input */
|
|
inputLen -= byteCount;
|
|
/* move to next word of output */
|
|
pOutWord++;
|
|
/* inWord has been consumed, but there may be bytes in nextInWord */
|
|
inWord = nextInWord;
|
|
} else {
|
|
/* output is word-aligned */
|
|
pOutWord = (WORD *)output;
|
|
if (inOffset) {
|
|
/* Input is not word-aligned. The first word load of input
|
|
* will not produce a full word of input bytes, so one word
|
|
* must be pre-loaded. The main loop below will load in the
|
|
* next input word and shift some of its bytes into inWord
|
|
* in order to create a full input word. Note that the main
|
|
* loop must execute at least once because the input must
|
|
* be at least two words.
|
|
*/
|
|
inWord = *pInWord++; /* UMR? see comments above. */
|
|
inWord = inWord LSH invBufShift;
|
|
} else {
|
|
/* Input is word-aligned. The first word load of input
|
|
* will produce a full word of input bytes, so nothing
|
|
* needs to be loaded here.
|
|
*/
|
|
inWord = 0;
|
|
}
|
|
}
|
|
/* Output buffer is aligned, inOffset is now measured relative to
|
|
* outOffset (and not a word boundary).
|
|
*/
|
|
inOffset = (inOffset + WORDSIZE - outOffset) % WORDSIZE;
|
|
/*****************************************************************/
|
|
/* Step 2: main loop */
|
|
/* At this point the output buffer is word-aligned. Any unused */
|
|
/* bytes from above will be in inWord (shifted correctly). If */
|
|
/* the input buffer is unaligned relative to the output buffer, */
|
|
/* shifting has to be done. */
|
|
/*****************************************************************/
|
|
if (inOffset) {
|
|
for (; inputLen >= WORDSIZE; inputLen -= WORDSIZE) {
|
|
nextInWord = *pInWord++;
|
|
inWord |= nextInWord RSH bufShift;
|
|
nextInWord = nextInWord LSH invBufShift;
|
|
ARCFOUR_NEXT_WORD();
|
|
*pOutWord++ = inWord ^ streamWord;
|
|
inWord = nextInWord;
|
|
}
|
|
if (inputLen == 0) {
|
|
/* Nothing left to do. */
|
|
cx->i = tmpi;
|
|
cx->j = tmpj;
|
|
return SECSuccess;
|
|
}
|
|
/* If the amount of remaining input is greater than the amount
|
|
* bytes pulled from the current input word, need to do another
|
|
* word load. What's left in inWord will be consumed in step 3.
|
|
*/
|
|
if (inputLen > WORDSIZE - inOffset)
|
|
inWord |= *pInWord RSH bufShift; /* UMR? See above. */
|
|
} else {
|
|
for (; inputLen >= WORDSIZE; inputLen -= WORDSIZE) {
|
|
inWord = *pInWord++;
|
|
ARCFOUR_NEXT_WORD();
|
|
*pOutWord++ = inWord ^ streamWord;
|
|
}
|
|
if (inputLen == 0) {
|
|
/* Nothing left to do. */
|
|
cx->i = tmpi;
|
|
cx->j = tmpj;
|
|
return SECSuccess;
|
|
} else {
|
|
/* A partial input word remains at the tail. Load it.
|
|
* The relevant bytes will be consumed in step 3.
|
|
*/
|
|
inWord = *pInWord; /* UMR? See comments above */
|
|
}
|
|
}
|
|
/*****************************************************************/
|
|
/* Step 3: */
|
|
/* A partial word of input remains, and it is already loaded */
|
|
/* into nextInWord. Shift appropriately and consume the bytes */
|
|
/* used in the partial word. */
|
|
/*****************************************************************/
|
|
mask = streamWord = 0;
|
|
#ifdef IS_LITTLE_ENDIAN
|
|
for (i = 0; i < inputLen; ++i) {
|
|
#else
|
|
for (i = WORDSIZE - 1; i >= WORDSIZE - inputLen; --i) {
|
|
#endif
|
|
ARCFOUR_NEXT_BYTE();
|
|
streamWord |= (WORD)(cx->S[t]) << 8*i;
|
|
mask |= MASK1BYTE << 8*i;
|
|
} /* } */
|
|
/* UMR? See comments above. */
|
|
*pOutWord = (*pOutWord & ~mask) | ((inWord ^ streamWord) & mask);
|
|
cx->i = tmpi;
|
|
cx->j = tmpj;
|
|
return SECSuccess;
|
|
}
|
|
#endif
|
|
#endif /* NSS_BEVAND_ARCFOUR */
|
|
|
|
SECStatus
|
|
RC4_Encrypt(RC4Context *cx, unsigned char *output,
|
|
unsigned int *outputLen, unsigned int maxOutputLen,
|
|
const unsigned char *input, unsigned int inputLen)
|
|
{
|
|
PORT_Assert(maxOutputLen >= inputLen);
|
|
if (maxOutputLen < inputLen) {
|
|
PORT_SetError(SEC_ERROR_INVALID_ARGS);
|
|
return SECFailure;
|
|
}
|
|
#if defined(NSS_BEVAND_ARCFOUR)
|
|
ARCFOUR(cx, inputLen, input, output);
|
|
*outputLen = inputLen;
|
|
return SECSuccess;
|
|
#elif defined( CONVERT_TO_WORDS )
|
|
/* Convert the byte-stream to a word-stream */
|
|
return rc4_wordconv(cx, output, outputLen, maxOutputLen, input, inputLen);
|
|
#else
|
|
/* Operate on bytes, but unroll the main loop */
|
|
return rc4_unrolled(cx, output, outputLen, maxOutputLen, input, inputLen);
|
|
#endif
|
|
}
|
|
|
|
SECStatus RC4_Decrypt(RC4Context *cx, unsigned char *output,
|
|
unsigned int *outputLen, unsigned int maxOutputLen,
|
|
const unsigned char *input, unsigned int inputLen)
|
|
{
|
|
PORT_Assert(maxOutputLen >= inputLen);
|
|
if (maxOutputLen < inputLen) {
|
|
PORT_SetError(SEC_ERROR_INVALID_ARGS);
|
|
return SECFailure;
|
|
}
|
|
/* decrypt and encrypt are same operation. */
|
|
#if defined(NSS_BEVAND_ARCFOUR)
|
|
ARCFOUR(cx, inputLen, input, output);
|
|
*outputLen = inputLen;
|
|
return SECSuccess;
|
|
#elif defined( CONVERT_TO_WORDS )
|
|
/* Convert the byte-stream to a word-stream */
|
|
return rc4_wordconv(cx, output, outputLen, maxOutputLen, input, inputLen);
|
|
#else
|
|
/* Operate on bytes, but unroll the main loop */
|
|
return rc4_unrolled(cx, output, outputLen, maxOutputLen, input, inputLen);
|
|
#endif
|
|
}
|
|
|
|
#undef CONVERT_TO_WORDS
|
|
#undef USE_WORD
|