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21#include "qemu/osdep.h"
22#include "qapi/error.h"
23#include "crypto/cipher.h"
24
25
26static size_t alg_key_len[QCRYPTO_CIPHER_ALG__MAX] = {
27 [QCRYPTO_CIPHER_ALG_AES_128] = 16,
28 [QCRYPTO_CIPHER_ALG_AES_192] = 24,
29 [QCRYPTO_CIPHER_ALG_AES_256] = 32,
30 [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
31 [QCRYPTO_CIPHER_ALG_CAST5_128] = 16,
32 [QCRYPTO_CIPHER_ALG_SERPENT_128] = 16,
33 [QCRYPTO_CIPHER_ALG_SERPENT_192] = 24,
34 [QCRYPTO_CIPHER_ALG_SERPENT_256] = 32,
35 [QCRYPTO_CIPHER_ALG_TWOFISH_128] = 16,
36 [QCRYPTO_CIPHER_ALG_TWOFISH_192] = 24,
37 [QCRYPTO_CIPHER_ALG_TWOFISH_256] = 32,
38};
39
40static size_t alg_block_len[QCRYPTO_CIPHER_ALG__MAX] = {
41 [QCRYPTO_CIPHER_ALG_AES_128] = 16,
42 [QCRYPTO_CIPHER_ALG_AES_192] = 16,
43 [QCRYPTO_CIPHER_ALG_AES_256] = 16,
44 [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
45 [QCRYPTO_CIPHER_ALG_CAST5_128] = 8,
46 [QCRYPTO_CIPHER_ALG_SERPENT_128] = 16,
47 [QCRYPTO_CIPHER_ALG_SERPENT_192] = 16,
48 [QCRYPTO_CIPHER_ALG_SERPENT_256] = 16,
49 [QCRYPTO_CIPHER_ALG_TWOFISH_128] = 16,
50 [QCRYPTO_CIPHER_ALG_TWOFISH_192] = 16,
51 [QCRYPTO_CIPHER_ALG_TWOFISH_256] = 16,
52};
53
54static bool mode_need_iv[QCRYPTO_CIPHER_MODE__MAX] = {
55 [QCRYPTO_CIPHER_MODE_ECB] = false,
56 [QCRYPTO_CIPHER_MODE_CBC] = true,
57 [QCRYPTO_CIPHER_MODE_XTS] = true,
58 [QCRYPTO_CIPHER_MODE_CTR] = true,
59};
60
61
62size_t qcrypto_cipher_get_block_len(QCryptoCipherAlgorithm alg)
63{
64 if (alg >= G_N_ELEMENTS(alg_key_len)) {
65 return 0;
66 }
67 return alg_block_len[alg];
68}
69
70
71size_t qcrypto_cipher_get_key_len(QCryptoCipherAlgorithm alg)
72{
73 if (alg >= G_N_ELEMENTS(alg_key_len)) {
74 return 0;
75 }
76 return alg_key_len[alg];
77}
78
79
80size_t qcrypto_cipher_get_iv_len(QCryptoCipherAlgorithm alg,
81 QCryptoCipherMode mode)
82{
83 if (alg >= G_N_ELEMENTS(alg_block_len)) {
84 return 0;
85 }
86 if (mode >= G_N_ELEMENTS(mode_need_iv)) {
87 return 0;
88 }
89
90 if (mode_need_iv[mode]) {
91 return alg_block_len[alg];
92 }
93 return 0;
94}
95
96
97static bool
98qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
99 QCryptoCipherMode mode,
100 size_t nkey,
101 Error **errp)
102{
103 if ((unsigned)alg >= QCRYPTO_CIPHER_ALG__MAX) {
104 error_setg(errp, "Cipher algorithm %d out of range",
105 alg);
106 return false;
107 }
108
109 if (mode == QCRYPTO_CIPHER_MODE_XTS) {
110 if (alg == QCRYPTO_CIPHER_ALG_DES_RFB) {
111 error_setg(errp, "XTS mode not compatible with DES-RFB");
112 return false;
113 }
114 if (nkey % 2) {
115 error_setg(errp, "XTS cipher key length should be a multiple of 2");
116 return false;
117 }
118
119 if (alg_key_len[alg] != (nkey / 2)) {
120 error_setg(errp, "Cipher key length %zu should be %zu",
121 nkey, alg_key_len[alg] * 2);
122 return false;
123 }
124 } else {
125 if (alg_key_len[alg] != nkey) {
126 error_setg(errp, "Cipher key length %zu should be %zu",
127 nkey, alg_key_len[alg]);
128 return false;
129 }
130 }
131 return true;
132}
133
134#if defined(CONFIG_GCRYPT) || defined(CONFIG_NETTLE)
135static uint8_t *
136qcrypto_cipher_munge_des_rfb_key(const uint8_t *key,
137 size_t nkey)
138{
139 uint8_t *ret = g_new0(uint8_t, nkey);
140 size_t i;
141 for (i = 0; i < nkey; i++) {
142 uint8_t r = key[i];
143 r = (r & 0xf0) >> 4 | (r & 0x0f) << 4;
144 r = (r & 0xcc) >> 2 | (r & 0x33) << 2;
145 r = (r & 0xaa) >> 1 | (r & 0x55) << 1;
146 ret[i] = r;
147 }
148 return ret;
149}
150#endif
151
152#ifdef CONFIG_GCRYPT
153#include "crypto/cipher-gcrypt.c"
154#elif defined CONFIG_NETTLE
155#include "crypto/cipher-nettle.c"
156#else
157#include "crypto/cipher-builtin.c"
158#endif
159