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27 lines
459 B
27 lines
459 B
10 years ago
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#include <string.h>
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/* Implements a constant time version of strcmp()
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* Will return 1 if a and b are equal, 0 if they are not */
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int slow_equals(const char* a, const char* b)
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{
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size_t lena, lenb, diff, i;
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lena = strlen(a);
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lenb = strlen(b);
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diff = strlen(a) ^ strlen(b);
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for(i=0; i<lena && i<lenb; i++)
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{
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diff |= a[i] ^ b[i];
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}
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if (diff == 0)
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{
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return 1;
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}
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else
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{
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return 0;
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}
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}
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