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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
use libc::c_int;
use std::ptr;

use crate::cvt;
use crate::error::ErrorStack;
use crate::hash::MessageDigest;
use crate::symm::Cipher;
use openssl_macros::corresponds;

#[derive(Clone, Eq, PartialEq, Hash, Debug)]
pub struct KeyIvPair {
    pub key: Vec<u8>,
    pub iv: Option<Vec<u8>>,
}

/// Derives a key and an IV from various parameters.
///
/// If specified, `salt` must be 8 bytes in length.
///
/// If the total key and IV length is less than 16 bytes and MD5 is used then
/// the algorithm is compatible with the key derivation algorithm from PKCS#5
/// v1.5 or PBKDF1 from PKCS#5 v2.0.
///
/// New applications should not use this and instead use
/// `pbkdf2_hmac` or another more modern key derivation algorithm.
#[corresponds(EVP_BytesToKey)]
#[allow(clippy::useless_conversion)]
pub fn bytes_to_key(
    cipher: Cipher,
    digest: MessageDigest,
    data: &[u8],
    salt: Option<&[u8]>,
    count: i32,
) -> Result<KeyIvPair, ErrorStack> {
    unsafe {
        assert!(data.len() <= c_int::max_value() as usize);
        let salt_ptr = match salt {
            Some(salt) => {
                assert_eq!(salt.len(), ffi::PKCS5_SALT_LEN as usize);
                salt.as_ptr()
            }
            None => ptr::null(),
        };

        ffi::init();

        let mut iv = cipher.iv_len().map(|l| vec![0; l]);

        let cipher = cipher.as_ptr();
        let digest = digest.as_ptr();

        let len = cvt(ffi::EVP_BytesToKey(
            cipher,
            digest,
            salt_ptr,
            ptr::null(),
            data.len() as c_int,
            count.into(),
            ptr::null_mut(),
            ptr::null_mut(),
        ))?;

        let mut key = vec![0; len as usize];
        let iv_ptr = iv
            .as_mut()
            .map(|v| v.as_mut_ptr())
            .unwrap_or(ptr::null_mut());

        cvt(ffi::EVP_BytesToKey(
            cipher,
            digest,
            salt_ptr,
            data.as_ptr(),
            data.len() as c_int,
            count as c_int,
            key.as_mut_ptr(),
            iv_ptr,
        ))?;

        Ok(KeyIvPair { key, iv })
    }
}

/// Derives a key from a password and salt using the PBKDF2-HMAC algorithm with a digest function.
#[corresponds(PKCS5_PBKDF2_HMAC)]
pub fn pbkdf2_hmac(
    pass: &[u8],
    salt: &[u8],
    iter: usize,
    hash: MessageDigest,
    key: &mut [u8],
) -> Result<(), ErrorStack> {
    unsafe {
        assert!(pass.len() <= c_int::max_value() as usize);
        assert!(salt.len() <= c_int::max_value() as usize);
        assert!(key.len() <= c_int::max_value() as usize);

        ffi::init();
        cvt(ffi::PKCS5_PBKDF2_HMAC(
            pass.as_ptr() as *const _,
            pass.len() as c_int,
            salt.as_ptr(),
            salt.len() as c_int,
            iter as c_int,
            hash.as_ptr(),
            key.len() as c_int,
            key.as_mut_ptr(),
        ))
        .map(|_| ())
    }
}

/// Derives a key from a password and salt using the scrypt algorithm.
///
/// Requires OpenSSL 1.1.0 or newer.
#[corresponds(EVP_PBE_scrypt)]
#[cfg(any(ossl110))]
pub fn scrypt(
    pass: &[u8],
    salt: &[u8],
    n: u64,
    r: u64,
    p: u64,
    maxmem: u64,
    key: &mut [u8],
) -> Result<(), ErrorStack> {
    unsafe {
        ffi::init();
        cvt(ffi::EVP_PBE_scrypt(
            pass.as_ptr() as *const _,
            pass.len(),
            salt.as_ptr() as *const _,
            salt.len(),
            n,
            r,
            p,
            maxmem,
            key.as_mut_ptr() as *mut _,
            key.len(),
        ))
        .map(|_| ())
    }
}

#[cfg(test)]
mod tests {
    use crate::hash::MessageDigest;
    use crate::symm::Cipher;

    // Test vectors from
    // https://git.lysator.liu.se/nettle/nettle/blob/nettle_3.1.1_release_20150424/testsuite/pbkdf2-test.c
    #[test]
    fn pbkdf2_hmac_sha256() {
        let mut buf = [0; 16];

        super::pbkdf2_hmac(b"passwd", b"salt", 1, MessageDigest::sha256(), &mut buf).unwrap();
        assert_eq!(
            buf,
            &[
                0x55_u8, 0xac_u8, 0x04_u8, 0x6e_u8, 0x56_u8, 0xe3_u8, 0x08_u8, 0x9f_u8, 0xec_u8,
                0x16_u8, 0x91_u8, 0xc2_u8, 0x25_u8, 0x44_u8, 0xb6_u8, 0x05_u8,
            ][..]
        );

        super::pbkdf2_hmac(
            b"Password",
            b"NaCl",
            80000,
            MessageDigest::sha256(),
            &mut buf,
        )
        .unwrap();
        assert_eq!(
            buf,
            &[
                0x4d_u8, 0xdc_u8, 0xd8_u8, 0xf6_u8, 0x0b_u8, 0x98_u8, 0xbe_u8, 0x21_u8, 0x83_u8,
                0x0c_u8, 0xee_u8, 0x5e_u8, 0xf2_u8, 0x27_u8, 0x01_u8, 0xf9_u8,
            ][..]
        );
    }

    // Test vectors from
    // https://git.lysator.liu.se/nettle/nettle/blob/nettle_3.1.1_release_20150424/testsuite/pbkdf2-test.c
    #[test]
    fn pbkdf2_hmac_sha512() {
        let mut buf = [0; 64];

        super::pbkdf2_hmac(b"password", b"NaCL", 1, MessageDigest::sha512(), &mut buf).unwrap();
        assert_eq!(
            &buf[..],
            &[
                0x73_u8, 0xde_u8, 0xcf_u8, 0xa5_u8, 0x8a_u8, 0xa2_u8, 0xe8_u8, 0x4f_u8, 0x94_u8,
                0x77_u8, 0x1a_u8, 0x75_u8, 0x73_u8, 0x6b_u8, 0xb8_u8, 0x8b_u8, 0xd3_u8, 0xc7_u8,
                0xb3_u8, 0x82_u8, 0x70_u8, 0xcf_u8, 0xb5_u8, 0x0c_u8, 0xb3_u8, 0x90_u8, 0xed_u8,
                0x78_u8, 0xb3_u8, 0x05_u8, 0x65_u8, 0x6a_u8, 0xf8_u8, 0x14_u8, 0x8e_u8, 0x52_u8,
                0x45_u8, 0x2b_u8, 0x22_u8, 0x16_u8, 0xb2_u8, 0xb8_u8, 0x09_u8, 0x8b_u8, 0x76_u8,
                0x1f_u8, 0xc6_u8, 0x33_u8, 0x60_u8, 0x60_u8, 0xa0_u8, 0x9f_u8, 0x76_u8, 0x41_u8,
                0x5e_u8, 0x9f_u8, 0x71_u8, 0xea_u8, 0x47_u8, 0xf9_u8, 0xe9_u8, 0x06_u8, 0x43_u8,
                0x06_u8,
            ][..]
        );

        super::pbkdf2_hmac(
            b"pass\0word",
            b"sa\0lt",
            1,
            MessageDigest::sha512(),
            &mut buf,
        )
        .unwrap();
        assert_eq!(
            &buf[..],
            &[
                0x71_u8, 0xa0_u8, 0xec_u8, 0x84_u8, 0x2a_u8, 0xbd_u8, 0x5c_u8, 0x67_u8, 0x8b_u8,
                0xcf_u8, 0xd1_u8, 0x45_u8, 0xf0_u8, 0x9d_u8, 0x83_u8, 0x52_u8, 0x2f_u8, 0x93_u8,
                0x36_u8, 0x15_u8, 0x60_u8, 0x56_u8, 0x3c_u8, 0x4d_u8, 0x0d_u8, 0x63_u8, 0xb8_u8,
                0x83_u8, 0x29_u8, 0x87_u8, 0x10_u8, 0x90_u8, 0xe7_u8, 0x66_u8, 0x04_u8, 0xa4_u8,
                0x9a_u8, 0xf0_u8, 0x8f_u8, 0xe7_u8, 0xc9_u8, 0xf5_u8, 0x71_u8, 0x56_u8, 0xc8_u8,
                0x79_u8, 0x09_u8, 0x96_u8, 0xb2_u8, 0x0f_u8, 0x06_u8, 0xbc_u8, 0x53_u8, 0x5e_u8,
                0x5a_u8, 0xb5_u8, 0x44_u8, 0x0d_u8, 0xf7_u8, 0xe8_u8, 0x78_u8, 0x29_u8, 0x6f_u8,
                0xa7_u8,
            ][..]
        );

        super::pbkdf2_hmac(
            b"passwordPASSWORDpassword",
            b"salt\0\0\0",
            50,
            MessageDigest::sha512(),
            &mut buf,
        )
        .unwrap();
        assert_eq!(
            &buf[..],
            &[
                0x01_u8, 0x68_u8, 0x71_u8, 0xa4_u8, 0xc4_u8, 0xb7_u8, 0x5f_u8, 0x96_u8, 0x85_u8,
                0x7f_u8, 0xd2_u8, 0xb9_u8, 0xf8_u8, 0xca_u8, 0x28_u8, 0x02_u8, 0x3b_u8, 0x30_u8,
                0xee_u8, 0x2a_u8, 0x39_u8, 0xf5_u8, 0xad_u8, 0xca_u8, 0xc8_u8, 0xc9_u8, 0x37_u8,
                0x5f_u8, 0x9b_u8, 0xda_u8, 0x1c_u8, 0xcd_u8, 0x1b_u8, 0x6f_u8, 0x0b_u8, 0x2f_u8,
                0xc3_u8, 0xad_u8, 0xda_u8, 0x50_u8, 0x54_u8, 0x12_u8, 0xe7_u8, 0x9d_u8, 0x89_u8,
                0x00_u8, 0x56_u8, 0xc6_u8, 0x2e_u8, 0x52_u8, 0x4c_u8, 0x7d_u8, 0x51_u8, 0x15_u8,
                0x4b_u8, 0x1a_u8, 0x85_u8, 0x34_u8, 0x57_u8, 0x5b_u8, 0xd0_u8, 0x2d_u8, 0xee_u8,
                0x39_u8,
            ][..]
        );
    }

    #[test]
    fn bytes_to_key() {
        let salt = [16_u8, 34_u8, 19_u8, 23_u8, 141_u8, 4_u8, 207_u8, 221_u8];

        let data = [
            143_u8, 210_u8, 75_u8, 63_u8, 214_u8, 179_u8, 155_u8, 241_u8, 242_u8, 31_u8, 154_u8,
            56_u8, 198_u8, 145_u8, 192_u8, 64_u8, 2_u8, 245_u8, 167_u8, 220_u8, 55_u8, 119_u8,
            233_u8, 136_u8, 139_u8, 27_u8, 71_u8, 242_u8, 119_u8, 175_u8, 65_u8, 207_u8,
        ];

        let expected_key = vec![
            249_u8, 115_u8, 114_u8, 97_u8, 32_u8, 213_u8, 165_u8, 146_u8, 58_u8, 87_u8, 234_u8,
            3_u8, 43_u8, 250_u8, 97_u8, 114_u8, 26_u8, 98_u8, 245_u8, 246_u8, 238_u8, 177_u8,
            229_u8, 161_u8, 183_u8, 224_u8, 174_u8, 3_u8, 6_u8, 244_u8, 236_u8, 255_u8,
        ];
        let expected_iv = vec![
            4_u8, 223_u8, 153_u8, 219_u8, 28_u8, 142_u8, 234_u8, 68_u8, 227_u8, 69_u8, 98_u8,
            107_u8, 208_u8, 14_u8, 236_u8, 60_u8,
        ];

        assert_eq!(
            super::bytes_to_key(
                Cipher::aes_256_cbc(),
                MessageDigest::sha1(),
                &data,
                Some(&salt),
                1,
            )
            .unwrap(),
            super::KeyIvPair {
                key: expected_key,
                iv: Some(expected_iv),
            }
        );
    }

    #[test]
    #[cfg(any(ossl110))]
    fn scrypt() {
        let pass = "pleaseletmein";
        let salt = "SodiumChloride";
        let expected =
            "7023bdcb3afd7348461c06cd81fd38ebfda8fbba904f8e3ea9b543f6545da1f2d5432955613\
             f0fcf62d49705242a9af9e61e85dc0d651e40dfcf017b45575887";

        let mut actual = [0; 64];
        super::scrypt(
            pass.as_bytes(),
            salt.as_bytes(),
            16384,
            8,
            1,
            0,
            &mut actual,
        )
        .unwrap();
        assert_eq!(hex::encode(&actual[..]), expected);
    }
}