Coverage Report

Created: 2024-11-21 07:03

/src/openssl/crypto/des/cfb_enc.c
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Count
Source (jump to first uncovered line)
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/*
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 * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
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 *
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 * Licensed under the Apache License 2.0 (the "License").  You may not use
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 * this file except in compliance with the License.  You can obtain a copy
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 * in the file LICENSE in the source distribution or at
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 * https://www.openssl.org/source/license.html
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 */
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/*
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 * DES low level APIs are deprecated for public use, but still ok for internal
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 * use.
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 */
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#include "internal/deprecated.h"
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#include "internal/e_os.h"
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#include "des_local.h"
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#include <assert.h>
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/*
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 * The input and output are loaded in multiples of 8 bits. What this means is
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 * that if you hame numbits=12 and length=2 the first 12 bits will be
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 * retrieved from the first byte and half the second.  The second 12 bits
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 * will come from the 3rd and half the 4th byte.
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 */
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/*
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 * Until Aug 1 2003 this function did not correctly implement CFB-r, so it
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 * will not be compatible with any encryption prior to that date. Ben.
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 */
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void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
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                     long length, DES_key_schedule *schedule,
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                     DES_cblock *ivec, int enc)
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0
{
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0
    register DES_LONG d0, d1, v0, v1;
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0
    register unsigned long l = length;
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    register int num = numbits / 8, n = (numbits + 7) / 8, i, rem =
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        numbits % 8;
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    DES_LONG ti[2];
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    unsigned char *iv;
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#ifndef L_ENDIAN
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    unsigned char ovec[16];
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#else
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0
    unsigned int sh[4];
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0
    unsigned char *ovec = (unsigned char *)sh;
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    /* I kind of count that compiler optimizes away this assertion, */
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    assert(sizeof(sh[0]) == 4); /* as this holds true for all, */
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    /* but 16-bit platforms...      */
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#endif
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    if (numbits <= 0 || numbits > 64)
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0
        return;
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    iv = &(*ivec)[0];
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    c2l(iv, v0);
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0
    c2l(iv, v1);
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    if (enc) {
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0
        while (l >= (unsigned long)n) {
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0
            l -= n;
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0
            ti[0] = v0;
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            ti[1] = v1;
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            DES_encrypt1((DES_LONG *)ti, schedule, DES_ENCRYPT);
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            c2ln(in, d0, d1, n);
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            in += n;
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            d0 ^= ti[0];
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            d1 ^= ti[1];
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            l2cn(d0, d1, out, n);
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            out += n;
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            /*
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             * 30-08-94 - eay - changed because l>>32 and l<<32 are bad under
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             * gcc :-(
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             */
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0
            if (numbits == 32) {
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0
                v0 = v1;
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0
                v1 = d0;
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0
            } else if (numbits == 64) {
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                v0 = d0;
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                v1 = d1;
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            } else {
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#ifndef L_ENDIAN
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                iv = &ovec[0];
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                l2c(v0, iv);
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                l2c(v1, iv);
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                l2c(d0, iv);
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                l2c(d1, iv);
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#else
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0
                sh[0] = v0, sh[1] = v1, sh[2] = d0, sh[3] = d1;
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0
#endif
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                if (rem == 0)
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                    memmove(ovec, ovec + num, 8);
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                else
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                    for (i = 0; i < 8; ++i)
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                        ovec[i] = ovec[i + num] << rem |
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                            ovec[i + num + 1] >> (8 - rem);
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#ifdef L_ENDIAN
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                v0 = sh[0], v1 = sh[1];
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#else
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                iv = &ovec[0];
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                c2l(iv, v0);
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                c2l(iv, v1);
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#endif
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            }
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        }
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    } else {
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        while (l >= (unsigned long)n) {
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            l -= n;
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            ti[0] = v0;
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            ti[1] = v1;
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            DES_encrypt1((DES_LONG *)ti, schedule, DES_ENCRYPT);
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            c2ln(in, d0, d1, n);
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            in += n;
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            /*
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             * 30-08-94 - eay - changed because l>>32 and l<<32 are bad under
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             * gcc :-(
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             */
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0
            if (numbits == 32) {
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                v0 = v1;
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                v1 = d0;
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            } else if (numbits == 64) {
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                v0 = d0;
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                v1 = d1;
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0
            } else {
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#ifndef L_ENDIAN
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                iv = &ovec[0];
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                l2c(v0, iv);
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                l2c(v1, iv);
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                l2c(d0, iv);
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                l2c(d1, iv);
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#else
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                sh[0] = v0, sh[1] = v1, sh[2] = d0, sh[3] = d1;
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0
#endif
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0
                if (rem == 0)
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                    memmove(ovec, ovec + num, 8);
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                else
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                    for (i = 0; i < 8; ++i)
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                        ovec[i] = ovec[i + num] << rem |
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                            ovec[i + num + 1] >> (8 - rem);
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#ifdef L_ENDIAN
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                v0 = sh[0], v1 = sh[1];
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#else
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                iv = &ovec[0];
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                c2l(iv, v0);
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                c2l(iv, v1);
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#endif
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            }
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            d0 ^= ti[0];
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            d1 ^= ti[1];
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            l2cn(d0, d1, out, n);
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            out += n;
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        }
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    }
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    iv = &(*ivec)[0];
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    l2c(v0, iv);
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    l2c(v1, iv);
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    v0 = v1 = d0 = d1 = ti[0] = ti[1] = 0;
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0
}