32 lines
629 B
Plaintext
32 lines
629 B
Plaintext
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/* search for a random prime with the specified amount of bits */
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\\ randomprime(bits:small=127)=
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\\ {
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\\ local(r:int=4);
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\\ while(!isprime(r),
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\\ r = bitor(2^(bits-1) + random(2^(bits-1)-1), 1);
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\\ );
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\\ r;
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\\ }
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smc_hextodec(s:str) =
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{
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local(v:vecsmall = Vecsmall(s), ret:int = 0);
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for(i = 1, #v,
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ret = (ret<<4) + if(v[i]<=57 && v[i]>=48, v[i]-48, v[i]<=70 && v[i]>=65, v[i]-55, v[i]<=102 && v[i]>=97, v[i]-87, error("invalid input format"))
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);
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ret;
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}
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smc_genfield(p:int, g)=
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{
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local(q:int);
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q = (p - 1) / 2;
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[Mod(g^2, p), q];
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}
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smc_genkeypair(field:vec)=
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{
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local(x:int=random(field[2]));
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[x, field[1]^x];
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}
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