diff options
| -rw-r--r-- | challenge/c02.go | 14 | ||||
| -rw-r--r-- | cryptopals.go | 2 | ||||
| -rw-r--r-- | enc/hex.go | 10 | ||||
| -rw-r--r-- | enc/xor.go | 19 |
4 files changed, 45 insertions, 0 deletions
diff --git a/challenge/c02.go b/challenge/c02.go new file mode 100644 index 0000000..deab152 --- /dev/null +++ b/challenge/c02.go @@ -0,0 +1,14 @@ +package challenge + +import ( + "fmt" + "ricketyspace.net/cryptopals/enc" +) + +func C2() { + a := "1c0111001f010100061a024b53535009181c" + b := "686974207468652062756c6c277320657965" + c := enc.FixedXOR(a, b) + + fmt.Printf("XOR(%v ^ %v) = %v\n", a, b, c) +} diff --git a/cryptopals.go b/cryptopals.go index 9c1c803..37580be 100644 --- a/cryptopals.go +++ b/cryptopals.go @@ -20,5 +20,7 @@ func main() { flag.PrintDefaults() case 1: challenge.C1() + case 2: + challenge.C2() } } @@ -14,3 +14,13 @@ func HexCharToDec(c byte) uint16 { } return 0 } + +func DecToHexChar(i uint16) byte { + switch { + case 0 <= i && i <= 9: + return byte(48 + i) + case 10 <= i && i <= 15: + return byte(97 + (i - 10)) + } + return 0 +} diff --git a/enc/xor.go b/enc/xor.go new file mode 100644 index 0000000..423c0a2 --- /dev/null +++ b/enc/xor.go @@ -0,0 +1,19 @@ +package enc + +func FixedXOR(a, b string) string { + cs := "" + if len(a) != len(b) { + return cs + } + + ab := []byte(a) + bb := []byte(b) + for i := 0; i < len(ab); i++ { + p := HexCharToDec(ab[i]) + q := HexCharToDec(bb[i]) + r := DecToHexChar(p ^ q) + + cs += string(r) + } + return cs +} |