Coverage Report

Created: 2025-06-22 06:56

/src/openssl/crypto/idea/i_skey.c
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Count
Source (jump to first uncovered line)
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/*
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 * Copyright 1995-2020 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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 * IDEA low level APIs are deprecated for public use, but still ok for internal
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 * use where we're using them to implement the higher level EVP interface, as is
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 * the case here.
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 */
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#include "internal/deprecated.h"
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#include <openssl/idea.h>
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#include "idea_local.h"
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static IDEA_INT inverse(unsigned int xin);
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void IDEA_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks)
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0
{
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0
    int i;
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0
    register IDEA_INT *kt, *kf, r0, r1, r2;
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0
    kt = &(ks->data[0][0]);
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0
    n2s(key, kt[0]);
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0
    n2s(key, kt[1]);
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0
    n2s(key, kt[2]);
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0
    n2s(key, kt[3]);
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0
    n2s(key, kt[4]);
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0
    n2s(key, kt[5]);
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0
    n2s(key, kt[6]);
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0
    n2s(key, kt[7]);
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0
    kf = kt;
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0
    kt += 8;
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0
    for (i = 0; i < 6; i++) {
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0
        r2 = kf[1];
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0
        r1 = kf[2];
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0
        *(kt++) = ((r2 << 9) | (r1 >> 7)) & 0xffff;
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0
        r0 = kf[3];
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0
        *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
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0
        r1 = kf[4];
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0
        *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
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0
        r0 = kf[5];
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0
        *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
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0
        r1 = kf[6];
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0
        *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
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0
        r0 = kf[7];
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0
        *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
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0
        r1 = kf[0];
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0
        if (i >= 5)
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0
            break;
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0
        *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
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0
        *(kt++) = ((r1 << 9) | (r2 >> 7)) & 0xffff;
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0
        kf += 8;
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0
    }
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0
}
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void IDEA_set_decrypt_key(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk)
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0
{
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0
    int r;
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0
    register IDEA_INT *fp, *tp, t;
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0
    tp = &(dk->data[0][0]);
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0
    fp = &(ek->data[8][0]);
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0
    for (r = 0; r < 9; r++) {
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0
        *(tp++) = inverse(fp[0]);
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0
        *(tp++) = ((int)(0x10000L - fp[2]) & 0xffff);
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0
        *(tp++) = ((int)(0x10000L - fp[1]) & 0xffff);
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0
        *(tp++) = inverse(fp[3]);
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0
        if (r == 8)
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0
            break;
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0
        fp -= 6;
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0
        *(tp++) = fp[4];
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0
        *(tp++) = fp[5];
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0
    }
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0
    tp = &(dk->data[0][0]);
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0
    t = tp[1];
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0
    tp[1] = tp[2];
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0
    tp[2] = t;
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0
    t = tp[49];
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0
    tp[49] = tp[50];
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0
    tp[50] = t;
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0
}
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/* taken directly from the 'paper' I'll have a look at it later */
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static IDEA_INT inverse(unsigned int xin)
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0
{
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0
    long n1, n2, q, r, b1, b2, t;
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0
    if (xin == 0)
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0
        b2 = 0;
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0
    else {
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        n1 = 0x10001;
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        n2 = xin;
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        b2 = 1;
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        b1 = 0;
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        do {
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0
            r = (n1 % n2);
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            q = (n1 - r) / n2;
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0
            if (r == 0) {
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0
                if (b2 < 0)
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0
                    b2 = 0x10001 + b2;
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0
            } else {
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                n1 = n2;
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                n2 = r;
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                t = b2;
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                b2 = b1 - q * b2;
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                b1 = t;
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0
            }
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0
        } while (r != 0);
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0
    }
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0
    return (IDEA_INT)b2;
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0
}