/
rsa.go
53 lines (44 loc) · 851 Bytes
/
rsa.go
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package rsa
func encrypt(plain string, e int, n int) string {
bytes := []byte(plain)
var encrypted []byte
for _, b := range bytes {
encrypted = append(encrypted, byte(int(b)^e%n))
}
return string(encrypted)
}
func decrypt(encrypted string, key rsa_key) string {
l := lcm(key.p-1, key.q-1)
d := 0
y := 0
for {
temp := d*key.e - y*l
if temp == 1 {
break
}
if temp < 1 {
d++
} else {
y++
}
}
var plain []byte
for _, v := range []byte(encrypted) {
plain = append(plain, byte(int(v)^d%key.n))
}
return string(plain)
}
func lcm(val1 int, val2 int) int {
gcd := Gcd(val1, val2)
return int(float64(val1) / float64(val2) * float64(gcd))
}
type rsa_key struct {
p, q, e, n int
}
func gen_keys(prime1 int, prime2 int) *rsa_key {
p := prime1
q := prime2
n := p * q
e := 2
return &rsa_key{p, q, n, int(e)}
}