28 lines
572 B
Go
28 lines
572 B
Go
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package back
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import (
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"bytes"
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"crypto/rand"
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"math/big"
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)
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var chars = []byte("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
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func SecureGenString(length int) (string, error) {
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charsLength := big.NewInt(int64(len(chars)))
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var maxN big.Int
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maxN.Exp(charsLength, big.NewInt(int64(length)), nil)
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n, err := rand.Int(rand.Reader, &maxN)
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if err != nil {
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return "", err
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}
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var buf bytes.Buffer
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for n.Cmp(&big.Int{}) == 1 {
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var charIdx big.Int
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n.DivMod(n, charsLength, &charIdx)
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_ = buf.WriteByte(chars[charIdx.Int64()])
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}
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return buf.String(), nil
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}
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