Coverage Report

Created: 2024-11-21 07:03

/src/openssl/crypto/modes/ofb128.c
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Source (jump to first uncovered line)
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/*
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 * Copyright 2008-2021 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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#include <string.h>
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#include <openssl/crypto.h>
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#include "crypto/modes.h"
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#if defined(__GNUC__) && !defined(STRICT_ALIGNMENT)
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typedef size_t size_t_aX __attribute((__aligned__(1)));
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#else
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typedef size_t size_t_aX;
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#endif
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/*
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 * The input and output encrypted as though 128bit ofb mode is being used.
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 * The extra state information to record how much of the 128bit block we have
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 * used is contained in *num;
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 */
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void CRYPTO_ofb128_encrypt(const unsigned char *in, unsigned char *out,
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                           size_t len, const void *key,
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                           unsigned char ivec[16], int *num, block128_f block)
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2.48k
{
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2.48k
    unsigned int n;
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2.48k
    size_t l = 0;
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2.48k
    if (*num < 0) {
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        /* There is no good way to signal an error return from here */
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0
        *num = -1;
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0
        return;
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0
    }
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2.48k
    n = *num;
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2.48k
#if !defined(OPENSSL_SMALL_FOOTPRINT)
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2.48k
    if (16 % sizeof(size_t) == 0) { /* always true actually */
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2.48k
        do {
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6.42k
            while (n && len) {
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3.93k
                *(out++) = *(in++) ^ ivec[n];
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3.93k
                --len;
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3.93k
                n = (n + 1) % 16;
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3.93k
            }
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# if defined(STRICT_ALIGNMENT)
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            if (((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) !=
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                0)
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                break;
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# endif
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7.52k
            while (len >= 16) {
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5.03k
                (*block) (ivec, ivec, key);
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15.1k
                for (; n < 16; n += sizeof(size_t))
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10.0k
                    *(size_t_aX *)(out + n) =
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10.0k
                        *(size_t_aX *)(in + n)
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10.0k
                        ^ *(size_t_aX *)(ivec + n);
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5.03k
                len -= 16;
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5.03k
                out += 16;
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5.03k
                in += 16;
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5.03k
                n = 0;
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5.03k
            }
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2.48k
            if (len) {
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800
                (*block) (ivec, ivec, key);
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2.89k
                while (len--) {
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2.09k
                    out[n] = in[n] ^ ivec[n];
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2.09k
                    ++n;
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2.09k
                }
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800
            }
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2.48k
            *num = n;
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2.48k
            return;
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2.48k
        } while (0);
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2.48k
    }
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    /* the rest would be commonly eliminated by x86* compiler */
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0
#endif
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0
    while (l < len) {
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0
        if (n == 0) {
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0
            (*block) (ivec, ivec, key);
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0
        }
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0
        out[l] = in[l] ^ ivec[n];
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0
        ++l;
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0
        n = (n + 1) % 16;
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0
    }
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    *num = n;
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0
}