1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

use u64x2::u64x2;

mod expand;

/// AES-256 block cipher instance
#[derive(Copy, Clone, Debug)]
pub struct Aes256 {
    encrypt_keys: [u64x2; 15],
    decrypt_keys: [u64x2; 15],
}

impl Aes256 {
    /// Create new AES-256 instance with given key
    #[inline]
    pub fn new(key: &[u8; 32]) -> Self {
        let (encrypt_keys, decrypt_keys) = expand::expand(key);
        Aes256 { encrypt_keys: encrypt_keys, decrypt_keys: decrypt_keys }
    }

    /// Encrypt in-place one 128 bit block
    #[inline]
    pub fn encrypt(&self, block: &mut [u8; 16]) {
        let keys = self.encrypt_keys;
        let mut data = u64x2::read(block);
        unsafe {
            asm!(include_str!("encrypt.asm")
                : "+{xmm0}"(data)
                :
                    "{xmm1}"(keys[0]), "{xmm2}"(keys[1]), "{xmm3}"(keys[2]),
                    "{xmm4}"(keys[3]), "{xmm5}"(keys[4]), "{xmm6}"(keys[5]),
                    "{xmm7}"(keys[6]), "{xmm8}"(keys[7]), "{xmm9}"(keys[8]),
                    "{xmm10}"(keys[9]), "{xmm11}"(keys[10]), "{xmm12}"(keys[11]),
                    "{xmm13}"(keys[12]), "{xmm14}"(keys[13]), "{xmm15}"(keys[14])
                :
                : "intel", "alignstack"
            );
        }
        data.write(block);
    }

    /// Decrypt in-place one 128 bit block
    #[inline]
    pub fn decrypt(&self, block: &mut [u8; 16]) {
        let keys = self.decrypt_keys;
        let mut data = u64x2::read(block);
        unsafe {
            asm!(include_str!("decrypt.asm")
                : "+{xmm0}"(data)
                :
                    "{xmm1}"(keys[14]), "{xmm2}"(keys[13]), "{xmm3}"(keys[12]),
                    "{xmm4}"(keys[11]), "{xmm5}"(keys[10]), "{xmm6}"(keys[9]),
                    "{xmm7}"(keys[8]), "{xmm8}"(keys[7]), "{xmm9}"(keys[6]),
                    "{xmm10}"(keys[5]), "{xmm11}"(keys[4]), "{xmm12}"(keys[3]),
                    "{xmm13}"(keys[2]), "{xmm14}"(keys[1]), "{xmm15}"(keys[0])
                :
                : "intel", "alignstack"
            );
        }
        data.write(block);
    }

    /// Encrypt in-place eight 128 bit blocks (1024 bits in total) using
    /// instruction-level parallelism
    #[inline]
    pub fn encrypt8(&self, blocks: &mut [u8; 8*16]) {
        let keys = self.encrypt_keys;
        let mut data = u64x2::read8(blocks);
        unsafe {
            asm!(include_str!("encrypt8_1.asm")
                :
                    "+{xmm0}"(data[0]), "+{xmm1}"(data[1]), "+{xmm2}"(data[2]),
                    "+{xmm3}"(data[3]), "+{xmm4}"(data[4]), "+{xmm5}"(data[5]),
                    "+{xmm6}"(data[6]), "+{xmm7}"(data[7])
                :
                    "{xmm8}"(keys[0]), "{xmm9}"(keys[1]), "{xmm10}"(keys[2]),
                    "{xmm11}"(keys[3]), "{xmm12}"(keys[4]), "{xmm13}"(keys[5]),
                    "{xmm14}"(keys[6]), "{xmm15}"(keys[7])
                :
                : "intel", "alignstack"
            );

            asm!(include_str!("encrypt8_2.asm")
                :
                    "+{xmm0}"(data[0]), "+{xmm1}"(data[1]), "+{xmm2}"(data[2]),
                    "+{xmm3}"(data[3]), "+{xmm4}"(data[4]), "+{xmm5}"(data[5]),
                    "+{xmm6}"(data[6]), "+{xmm7}"(data[7])
                :
                    "{xmm9}"(keys[8]), "{xmm10}"(keys[9]), "{xmm11}"(keys[10]),
                    "{xmm12}"(keys[11]), "{xmm13}"(keys[12]), "{xmm14}"(keys[13]),
                    "{xmm15}"(keys[14])
                :
                : "intel", "alignstack"
            );
        }
        u64x2::write8(data, blocks);
    }

    /// Decrypt in-place eight 128 bit blocks (1024 bits in total) using
    /// instruction-level parallelism
    #[inline]
    pub fn decrypt8(&self, blocks: &mut [u8; 8*16]) {
        let keys = self.decrypt_keys;
        let mut data = u64x2::read8(blocks);
        unsafe {
            asm!(include_str!("decrypt8_1.asm")
                :
                    "+{xmm0}"(data[0]), "+{xmm1}"(data[1]), "+{xmm2}"(data[2]),
                    "+{xmm3}"(data[3]), "+{xmm4}"(data[4]), "+{xmm5}"(data[5]),
                    "+{xmm6}"(data[6]), "+{xmm7}"(data[7])
                :
                    "{xmm8}"(keys[14]), "{xmm9}"(keys[13]), "{xmm10}"(keys[12]),
                    "{xmm11}"(keys[11]), "{xmm12}"(keys[10]), "{xmm13}"(keys[9]),
                    "{xmm14}"(keys[8]), "{xmm15}"(keys[7])
                :
                : "intel", "alignstack"
            );

            asm!(include_str!("decrypt8_2.asm")
                :
                    "+{xmm0}"(data[0]), "+{xmm1}"(data[1]), "+{xmm2}"(data[2]),
                    "+{xmm3}"(data[3]), "+{xmm4}"(data[4]), "+{xmm5}"(data[5]),
                    "+{xmm6}"(data[6]), "+{xmm7}"(data[7])
                :
                    "{xmm9}"(keys[6]), "{xmm10}"(keys[5]), "{xmm11}"(keys[4]),
                    "{xmm12}"(keys[3]), "{xmm13}"(keys[2]), "{xmm14}"(keys[1]),
                    "{xmm15}"(keys[0])
                :
                : "intel", "alignstack"
            );
        }
        u64x2::write8(data, blocks);
    }
}

#[cfg(test)]
mod test_expand;