├── go.mod ├── subtle ├── overlap.go └── purelap.go ├── iowrp.go ├── io_test.go ├── Readme.md ├── rabbit.go └── LICENSE /go.mod: -------------------------------------------------------------------------------- 1 | module github.com/sina-ghaderi/rabbitio 2 | 3 | go 1.17 4 | -------------------------------------------------------------------------------- /subtle/overlap.go: -------------------------------------------------------------------------------- 1 | //go:build !purego 2 | 3 | package subtle 4 | 5 | import "unsafe" 6 | 7 | func AnyOverlap(x, y []byte) bool { 8 | return len(x) > 0 && len(y) > 0 && 9 | uintptr(unsafe.Pointer(&x[0])) <= uintptr(unsafe.Pointer(&y[len(y)-1])) && 10 | uintptr(unsafe.Pointer(&y[0])) <= uintptr(unsafe.Pointer(&x[len(x)-1])) 11 | } 12 | 13 | func InexactOverlap(x, y []byte) bool { 14 | if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] { 15 | return false 16 | } 17 | return AnyOverlap(x, y) 18 | } 19 | -------------------------------------------------------------------------------- /subtle/purelap.go: -------------------------------------------------------------------------------- 1 | //go:build purego 2 | 3 | package subtle 4 | 5 | import "reflect" 6 | 7 | func AnyOverlap(x, y []byte) bool { 8 | return len(x) > 0 && len(y) > 0 && 9 | reflect.ValueOf(&x[0]).Pointer() <= reflect.ValueOf(&y[len(y)-1]).Pointer() && 10 | reflect.ValueOf(&y[0]).Pointer() <= reflect.ValueOf(&x[len(x)-1]).Pointer() 11 | } 12 | 13 | func InexactOverlap(x, y []byte) bool { 14 | if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] { 15 | return false 16 | } 17 | return AnyOverlap(x, y) 18 | } 19 | -------------------------------------------------------------------------------- /iowrp.go: -------------------------------------------------------------------------------- 1 | package rabbitio 2 | 3 | import ( 4 | "crypto/cipher" 5 | "io" 6 | ) 7 | 8 | // NewWriterCipher warp a rabbit cipher stream with an io.Writer, returned StreamWriter 9 | // interface which can be used to encrypt or decrypting data 10 | func NewWriterCipher(key []byte, iv []byte, wr io.Writer) (*cipher.StreamWriter, error) { 11 | stream, err := NewCipher(key, iv) 12 | if err != nil { 13 | return nil, err 14 | } 15 | return &cipher.StreamWriter{S: stream, W: wr}, err 16 | } 17 | 18 | // NewWriterCipher warp a rabbit cipher stream with an io.Reader, returned StreamReader 19 | // interface which can be used to encrypt or decrypting data 20 | func NewReaderCipher(key []byte, iv []byte, re io.Reader) (*cipher.StreamReader, error) { 21 | stream, err := NewCipher(key, iv) 22 | if err != nil { 23 | return nil, err 24 | } 25 | return &cipher.StreamReader{S: stream, R: re}, err 26 | } 27 | -------------------------------------------------------------------------------- /io_test.go: -------------------------------------------------------------------------------- 1 | package rabbitio_test 2 | 3 | import ( 4 | "bytes" 5 | "encoding/hex" 6 | "fmt" 7 | "io" 8 | "strings" 9 | "testing" 10 | 11 | "github.com/sina-ghaderi/rabbitio" 12 | ) 13 | 14 | func TestNewWriterCipher(t *testing.T) { 15 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 16 | txt := "dummy text to test NewWriterCipher" 17 | twr := strings.NewReader(txt) 18 | 19 | iw := new(bytes.Buffer) 20 | 21 | t.Logf("encrypting plain text ---") 22 | cw, err := rabbitio.NewWriterCipher(key, ivt, iw) 23 | if err != nil { 24 | t.Fatal(err) 25 | } 26 | 27 | if _, err := io.Copy(cw, twr); err != nil { 28 | t.Fatal(err) 29 | } 30 | 31 | t.Logf("cipher-text: %v", hex.EncodeToString(iw.Bytes())) 32 | t.Logf("decrypting cipher text ---") 33 | 34 | ir := new(bytes.Buffer) 35 | cr, err := rabbitio.NewWriterCipher(key, ivt, ir) 36 | if err != nil { 37 | t.Fatal(err) 38 | } 39 | 40 | if _, err := io.Copy(cr, iw); err != nil { 41 | t.Fatal(err) 42 | } 43 | 44 | if ir.String() != txt { 45 | t.Error("error: ir.String() is not equal to txt") 46 | } 47 | } 48 | 49 | func TestNewReaderCipher(t *testing.T) { 50 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 51 | txt := "test NewReadercipher text dummy tx" 52 | twr := strings.NewReader(txt) 53 | 54 | iw := new(bytes.Buffer) 55 | 56 | t.Logf("encrypting plain text ---") 57 | cw, err := rabbitio.NewReaderCipher(key, ivt, twr) 58 | if err != nil { 59 | t.Fatal(err) 60 | } 61 | 62 | if _, err := io.Copy(iw, cw); err != nil { 63 | t.Fatal(err) 64 | } 65 | 66 | t.Logf("cipher-text: %v", hex.EncodeToString(iw.Bytes())) 67 | t.Logf("decrypting cipher text ---") 68 | 69 | ir := new(bytes.Buffer) 70 | cr, err := rabbitio.NewReaderCipher(key, ivt, iw) 71 | if err != nil { 72 | t.Fatal(err) 73 | } 74 | 75 | if _, err := io.Copy(ir, cr); err != nil { 76 | t.Fatal(err) 77 | } 78 | 79 | if ir.String() != txt { 80 | t.Error("error: ir.String() is not equal to txt") 81 | } 82 | } 83 | 84 | func TestNewCipher(t *testing.T) { 85 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 86 | txt := "test NewReadercipher text dummy tx" 87 | cph, err := rabbitio.NewCipher(key, ivt) 88 | if err != nil { 89 | t.Fatal(err) 90 | } 91 | dst := make([]byte, len(txt)) 92 | cph.XORKeyStream(dst, []byte(txt)) 93 | t.Logf("cipher-text: %v", hex.EncodeToString(dst)) 94 | 95 | cph, err = rabbitio.NewCipher(key, ivt) 96 | if err != nil { 97 | t.Fatal(err) 98 | } 99 | 100 | nds := make([]byte, len(dst)) 101 | cph.XORKeyStream(nds, dst) 102 | if string(nds) != txt { 103 | t.Error("error: nds is not equal to txt") 104 | } 105 | 106 | } 107 | 108 | func BenchmarkNewCipher(b *testing.B) { 109 | b.Run(fmt.Sprintf("bench %v", b.N), func(b *testing.B) { 110 | for i := 0; i < b.N; i++ { 111 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 112 | txt := "test NewReadercipher text dummy tx" 113 | cph, err := rabbitio.NewCipher(key, ivt) 114 | if err != nil { 115 | b.Fatal(err) 116 | } 117 | dst := make([]byte, len(txt)) 118 | cph.XORKeyStream(dst, []byte(txt)) 119 | 120 | cph, err = rabbitio.NewCipher(key, ivt) 121 | if err != nil { 122 | b.Fatal(err) 123 | } 124 | 125 | nds := make([]byte, len(dst)) 126 | cph.XORKeyStream(nds, dst) 127 | if string(nds) != txt { 128 | b.Error("error: nds is not equal to txt") 129 | } 130 | } 131 | }) 132 | 133 | } 134 | -------------------------------------------------------------------------------- /Readme.md: -------------------------------------------------------------------------------- 1 | # rabbitio 2 | rabbitio is a rabbit stream cipher packge based on [RFC 4503](https://datatracker.ietf.org/doc/html/rfc4503) for golang 3 | rabbit is a super-fast lightweight stream cipher which uses a 128-bit key and a 64-bit initialization vector, this cipher was designed in 2003 and released in 2008 4 | 5 | 6 | this is a mirror repository, rabbitio also lives on [snix.ir public git service](https://snix.ir/rabbitio) 7 | 8 | ### usage and docs 9 | simple encrypt/decrypting plain text and cipher text with rabbitio 10 | key must be exactly 16 byte len, iv is optional but must be either zero (for nothing) or 8 byte len 11 | you can replace `"snix.ir/rabbitio"` with `"github.com/sina-ghaderi/rabbitio"` to use github mirror repository 12 | 13 | ```go 14 | package main 15 | import ( 16 | "encoding/hex" 17 | "fmt" 18 | 19 | "snix.ir/rabbitio" 20 | ) 21 | 22 | 23 | func main() { 24 | key := []byte("key-gen-rabbitio") 25 | ivx := []byte("abcd8795") 26 | ptx := "plain text -- dummy text to encrypt and decrypt with rabbit" 27 | str, err := rabbitio.NewCipher(key, ivx) 28 | if err != nil { panic(err) } 29 | 30 | cpt := make([]byte, len(ptx)) 31 | str.XORKeyStream(cpt, []byte(ptx)) 32 | fmt.Println("cipher text ---:", hex.EncodeToString(cpt)) 33 | 34 | str, err = rabbitio.NewCipher(key, ivx) 35 | if err != nil { panic(err) } 36 | 37 | // decrypt cipher text and print orginal text 38 | plx := make([]byte, len(cpt)) 39 | str.XORKeyStream(plx, cpt) 40 | fmt.Println("plain text ----:", string(plx)) 41 | } 42 | 43 | ``` 44 | 45 | io interfaces, reader and writer methods: working with writer 46 | 47 | ```go 48 | package main 49 | import ( 50 | "bytes" 51 | "encoding/hex" 52 | "fmt" 53 | "io" 54 | "strings" 55 | 56 | "snix.ir/rabbitio" 57 | ) 58 | 59 | func main() { 60 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 61 | txt := "dummy text to test NewWriterCipher" 62 | twr := strings.NewReader(txt) 63 | iw := new(bytes.Buffer) 64 | cw, err := rabbitio.NewWriterCipher(key, ivt, iw) 65 | if err != nil { 66 | panic(err) 67 | } 68 | if _, err := io.Copy(cw, twr); err != nil { 69 | panic(err) 70 | } 71 | fmt.Println("cipher-text:", hex.EncodeToString(iw.Bytes())) 72 | fmt.Println("decrypting cipher text ---") 73 | ir := new(bytes.Buffer) 74 | cr, err := rabbitio.NewWriterCipher(key, ivt, ir) 75 | if err != nil { 76 | panic(err) 77 | } 78 | if _, err := io.Copy(cr, iw); err != nil { 79 | panic(err) 80 | } 81 | fmt.Println(ir.String()) 82 | } 83 | ``` 84 | 85 | io interfaces, reader and writer methods: working with reader 86 | 87 | ```go 88 | package main 89 | import ( 90 | "bytes" 91 | "encoding/hex" 92 | "fmt" 93 | "io" 94 | "strings" 95 | 96 | "snix.ir/rabbitio" 97 | ) 98 | 99 | func main() { 100 | key, ivt := []byte("12345678abcdefgh"), []byte("1234qwer") 101 | txt := "test NewReadercipher text dummy tx" 102 | twr := strings.NewReader(txt) 103 | iw := new(bytes.Buffer) 104 | cw, err := rabbitio.NewReaderCipher(key, ivt, twr) 105 | if err != nil { 106 | panic(err) 107 | } 108 | if _, err := io.Copy(iw, cw); err != nil { 109 | panic(err) 110 | } 111 | fmt.Println("cipher-text:", hex.EncodeToString(iw.Bytes())) 112 | fmt.Println("decrypting cipher text ---") 113 | ir := new(bytes.Buffer) 114 | cr, err := rabbitio.NewReaderCipher(key, ivt, iw) 115 | if err != nil { 116 | panic(err) 117 | } 118 | if _, err := io.Copy(ir, cr); err != nil { 119 | panic(err) 120 | } 121 | fmt.Println(ir.String()) 122 | } 123 | 124 | ``` 125 | 126 | ### test and benchmarking 127 | unit test and benchmarking provided too, run `go test -v` or `go test -bench=. -benchmem` on project root directory 128 | 129 | 130 | 131 | feel free to email me sina@snix.ir if you want to contribute to this project 132 | 133 | Copyright 2022 SNIX LLC sina@snix.ir Apache License 134 | 135 | 136 | 137 | 138 | -------------------------------------------------------------------------------- /rabbit.go: -------------------------------------------------------------------------------- 1 | package rabbitio 2 | 3 | import ( 4 | "crypto/cipher" 5 | "encoding/binary" 6 | "errors" 7 | "math/bits" 8 | 9 | "github.com/sina-ghaderi/rabbitio/subtle" 10 | ) 11 | 12 | const ( 13 | KeyLen = 0x10 14 | IVXLen = 0x08 15 | ) 16 | 17 | var ( 18 | ErrInvalidKey = errors.New("rabbitio: rabbit key must be exactly 16 byte len") 19 | ErrInvalidIVX = errors.New("rabbitio: rabbit iv must be either 8 or zero byte len") 20 | ) 21 | 22 | var aro = []uint32{ 23 | 0x4D34D34D, 0xD34D34D3, 24 | 0x34D34D34, 0x4D34D34D, 25 | 0xD34D34D3, 0x34D34D34, 26 | 0x4D34D34D, 0xD34D34D3, 27 | } 28 | 29 | type rabbitCipher struct { 30 | xbit [8]uint32 31 | cbit [8]uint32 32 | ks []byte 33 | carry uint32 34 | sbit [16]byte 35 | } 36 | 37 | // NewCipher returns a chpher.Stream interface that implemented an XORKeyStream method 38 | // according to RFC 4503, key must be 16 byte len, iv on the other hand is optional but 39 | // must be either zero len or 8 byte len, error will be returned on wrong key/iv len 40 | func NewCipher(key []byte, iv []byte) (cipher.Stream, error) { 41 | if len(key) != KeyLen { 42 | return nil, ErrInvalidKey 43 | } 44 | if len(iv) != 0x00 && len(iv) != IVXLen { 45 | return nil, ErrInvalidIVX 46 | } 47 | var k [0x04]uint32 48 | for i := range k { 49 | k[i] = binary.LittleEndian.Uint32(key[i*0x04:]) 50 | } 51 | var r rabbitCipher 52 | r.setupKey(k[:]) 53 | if len(iv) != 0x00 { 54 | var v [0x04]uint16 55 | for i := range v { 56 | v[i] = binary.LittleEndian.Uint16(iv[i*0x02:]) 57 | } 58 | r.setupIV(v[:]) 59 | } 60 | return &r, nil 61 | } 62 | 63 | func (r *rabbitCipher) setupKey(key []uint32) { 64 | r.xbit[0] = key[0] 65 | r.xbit[1] = key[3]<<16 | key[2]>>16 66 | r.xbit[2] = key[1] 67 | r.xbit[3] = key[0]<<16 | key[3]>>16 68 | r.xbit[4] = key[2] 69 | r.xbit[5] = key[1]<<16 | key[0]>>16 70 | r.xbit[6] = key[3] 71 | r.xbit[7] = key[2]<<16 | key[1]>>16 72 | r.cbit[0] = bits.RotateLeft32(key[2], 0x10) 73 | r.cbit[1] = key[0]&0xffff0000 | key[1]&0xffff 74 | r.cbit[2] = bits.RotateLeft32(key[3], 0x10) 75 | r.cbit[3] = key[1]&0xffff0000 | key[2]&0xffff 76 | r.cbit[4] = bits.RotateLeft32(key[0], 0x10) 77 | r.cbit[5] = key[2]&0xffff0000 | key[3]&0xffff 78 | r.cbit[6] = bits.RotateLeft32(key[1], 0x10) 79 | r.cbit[7] = key[3]&0xffff0000 | key[0]&0xffff 80 | for i := 0; i < 4; i++ { 81 | r.nextState() 82 | } 83 | r.cbit[0] ^= r.xbit[4] 84 | r.cbit[1] ^= r.xbit[5] 85 | r.cbit[2] ^= r.xbit[6] 86 | r.cbit[3] ^= r.xbit[7] 87 | r.cbit[4] ^= r.xbit[0] 88 | r.cbit[5] ^= r.xbit[1] 89 | r.cbit[6] ^= r.xbit[2] 90 | r.cbit[7] ^= r.xbit[3] 91 | } 92 | 93 | func (r *rabbitCipher) setupIV(iv []uint16) { 94 | r.cbit[0] ^= uint32(iv[1])<<0x10 | uint32(iv[0]) 95 | r.cbit[1] ^= uint32(iv[3])<<0x10 | uint32(iv[1]) 96 | r.cbit[2] ^= uint32(iv[3])<<0x10 | uint32(iv[2]) 97 | r.cbit[3] ^= uint32(iv[2])<<0x10 | uint32(iv[0]) 98 | r.cbit[4] ^= uint32(iv[1])<<0x10 | uint32(iv[0]) 99 | r.cbit[5] ^= uint32(iv[3])<<0x10 | uint32(iv[1]) 100 | r.cbit[6] ^= uint32(iv[3])<<0x10 | uint32(iv[2]) 101 | r.cbit[7] ^= uint32(iv[2])<<0x10 | uint32(iv[0]) 102 | for i := 0; i < 4; i++ { 103 | r.nextState() 104 | } 105 | } 106 | 107 | func (r *rabbitCipher) nextState() { 108 | var GRX [0x08]uint32 109 | for i := range r.cbit { 110 | r.carry, r.cbit[i] = bits.Sub32(aro[i], r.cbit[i], r.carry) 111 | } 112 | for i := range GRX { 113 | GRX[i] = gfunction(r.xbit[i], r.cbit[i]) 114 | } 115 | r.xbit[0x00] = GRX[0] + bits.RotateLeft32(GRX[7], 0x10) + bits.RotateLeft32(GRX[6], 0x10) 116 | r.xbit[0x01] = GRX[1] + bits.RotateLeft32(GRX[0], 0x08) + GRX[7] 117 | r.xbit[0x02] = GRX[2] + bits.RotateLeft32(GRX[1], 0x10) + bits.RotateLeft32(GRX[0], 0x10) 118 | r.xbit[0x03] = GRX[3] + bits.RotateLeft32(GRX[2], 0x08) + GRX[1] 119 | r.xbit[0x04] = GRX[4] + bits.RotateLeft32(GRX[3], 0x10) + bits.RotateLeft32(GRX[2], 0x10) 120 | r.xbit[0x05] = GRX[5] + bits.RotateLeft32(GRX[4], 0x08) + GRX[3] 121 | r.xbit[0x06] = GRX[6] + bits.RotateLeft32(GRX[5], 0x10) + bits.RotateLeft32(GRX[4], 0x10) 122 | r.xbit[0x07] = GRX[7] + bits.RotateLeft32(GRX[6], 0x08) + GRX[5] 123 | } 124 | 125 | func (r *rabbitCipher) extract() { 126 | var sw [0x04]uint32 127 | r.nextState() 128 | sw[0] = r.xbit[0] ^ (r.xbit[5]>>0x10 | r.xbit[3]<<0x10) 129 | sw[1] = r.xbit[2] ^ (r.xbit[7]>>0x10 | r.xbit[5]<<0x10) 130 | sw[2] = r.xbit[4] ^ (r.xbit[1]>>0x10 | r.xbit[7]<<0x10) 131 | sw[3] = r.xbit[6] ^ (r.xbit[3]>>0x10 | r.xbit[1]<<0x10) 132 | for i := range sw { 133 | binary.LittleEndian.PutUint32(r.sbit[i*0x04:], sw[i]) 134 | } 135 | r.ks = r.sbit[:] 136 | } 137 | 138 | // XORKeyStream read from src and perform xor on every elemnt of src and 139 | // write result on dst 140 | func (r *rabbitCipher) XORKeyStream(dst, src []byte) { 141 | 142 | if len(dst) < len(src) { 143 | panic("rabbitio: output smaller than input") 144 | } 145 | 146 | if subtle.InexactOverlap(dst, src) { 147 | panic("rabbitio: invalid buffer memory overlap") 148 | } 149 | 150 | for i := range src { 151 | if len(r.ks) == 0x00 { 152 | r.extract() 153 | } 154 | dst[i] = src[i] ^ r.ks[0x00] 155 | r.ks = r.ks[0x01:] 156 | } 157 | } 158 | 159 | func gfunction(u, v uint32) uint32 { 160 | uv := uint64(u + v) 161 | uv *= uv 162 | return uint32(uv>>0x20) ^ uint32(uv) 163 | } 164 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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