xref: /openbmc/qemu/target/riscv/crypto_helper.c (revision e052944a)
1 /*
2  * RISC-V Crypto Emulation Helpers for QEMU.
3  *
4  * Copyright (c) 2021 Ruibo Lu, luruibo2000@163.com
5  * Copyright (c) 2021 Zewen Ye, lustrew@foxmail.com
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2 or later, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/exec-all.h"
23 #include "exec/helper-proto.h"
24 #include "crypto/aes.h"
25 #include "crypto/aes-round.h"
26 #include "crypto/sm4.h"
27 
28 #define AES_XTIME(a) \
29     ((a << 1) ^ ((a & 0x80) ? 0x1b : 0))
30 
31 #define AES_GFMUL(a, b) (( \
32     (((b) & 0x1) ? (a) : 0) ^ \
33     (((b) & 0x2) ? AES_XTIME(a) : 0) ^ \
34     (((b) & 0x4) ? AES_XTIME(AES_XTIME(a)) : 0) ^ \
35     (((b) & 0x8) ? AES_XTIME(AES_XTIME(AES_XTIME(a))) : 0)) & 0xFF)
36 
37 static inline uint32_t aes_mixcolumn_byte(uint8_t x, bool fwd)
38 {
39     uint32_t u;
40 
41     if (fwd) {
42         u = (AES_GFMUL(x, 3) << 24) | (x << 16) | (x << 8) |
43             (AES_GFMUL(x, 2) << 0);
44     } else {
45         u = (AES_GFMUL(x, 0xb) << 24) | (AES_GFMUL(x, 0xd) << 16) |
46             (AES_GFMUL(x, 0x9) << 8) | (AES_GFMUL(x, 0xe) << 0);
47     }
48     return u;
49 }
50 
51 #define sext32_xlen(x) (target_ulong)(int32_t)(x)
52 
53 static inline target_ulong aes32_operation(target_ulong shamt,
54                                            target_ulong rs1, target_ulong rs2,
55                                            bool enc, bool mix)
56 {
57     uint8_t si = rs2 >> shamt;
58     uint8_t so;
59     uint32_t mixed;
60     target_ulong res;
61 
62     if (enc) {
63         so = AES_sbox[si];
64         if (mix) {
65             mixed = aes_mixcolumn_byte(so, true);
66         } else {
67             mixed = so;
68         }
69     } else {
70         so = AES_isbox[si];
71         if (mix) {
72             mixed = aes_mixcolumn_byte(so, false);
73         } else {
74             mixed = so;
75         }
76     }
77     mixed = rol32(mixed, shamt);
78     res = rs1 ^ mixed;
79 
80     return sext32_xlen(res);
81 }
82 
83 target_ulong HELPER(aes32esmi)(target_ulong rs1, target_ulong rs2,
84                                target_ulong shamt)
85 {
86     return aes32_operation(shamt, rs1, rs2, true, true);
87 }
88 
89 target_ulong HELPER(aes32esi)(target_ulong rs1, target_ulong rs2,
90                               target_ulong shamt)
91 {
92     return aes32_operation(shamt, rs1, rs2, true, false);
93 }
94 
95 target_ulong HELPER(aes32dsmi)(target_ulong rs1, target_ulong rs2,
96                                target_ulong shamt)
97 {
98     return aes32_operation(shamt, rs1, rs2, false, true);
99 }
100 
101 target_ulong HELPER(aes32dsi)(target_ulong rs1, target_ulong rs2,
102                               target_ulong shamt)
103 {
104     return aes32_operation(shamt, rs1, rs2, false, false);
105 }
106 
107 static const AESState aes_zero = { };
108 
109 target_ulong HELPER(aes64esm)(target_ulong rs1, target_ulong rs2)
110 {
111     AESState t;
112 
113     t.d[HOST_BIG_ENDIAN] = rs1;
114     t.d[!HOST_BIG_ENDIAN] = rs2;
115     aesenc_SB_SR_MC_AK(&t, &t, &aes_zero, false);
116     return t.d[HOST_BIG_ENDIAN];
117 }
118 
119 target_ulong HELPER(aes64es)(target_ulong rs1, target_ulong rs2)
120 {
121     AESState t;
122 
123     t.d[HOST_BIG_ENDIAN] = rs1;
124     t.d[!HOST_BIG_ENDIAN] = rs2;
125     aesenc_SB_SR_AK(&t, &t, &aes_zero, false);
126     return t.d[HOST_BIG_ENDIAN];
127 }
128 
129 target_ulong HELPER(aes64ds)(target_ulong rs1, target_ulong rs2)
130 {
131     AESState t;
132 
133     t.d[HOST_BIG_ENDIAN] = rs1;
134     t.d[!HOST_BIG_ENDIAN] = rs2;
135     aesdec_ISB_ISR_AK(&t, &t, &aes_zero, false);
136     return t.d[HOST_BIG_ENDIAN];
137 }
138 
139 target_ulong HELPER(aes64dsm)(target_ulong rs1, target_ulong rs2)
140 {
141     AESState t, z = { };
142 
143     /*
144      * This instruction does not include a round key,
145      * so supply a zero to our primitive.
146      */
147     t.d[HOST_BIG_ENDIAN] = rs1;
148     t.d[!HOST_BIG_ENDIAN] = rs2;
149     aesdec_ISB_ISR_IMC_AK(&t, &t, &z, false);
150     return t.d[HOST_BIG_ENDIAN];
151 }
152 
153 target_ulong HELPER(aes64ks2)(target_ulong rs1, target_ulong rs2)
154 {
155     uint64_t RS1 = rs1;
156     uint64_t RS2 = rs2;
157     uint32_t rs1_hi = RS1 >> 32;
158     uint32_t rs2_lo = RS2;
159     uint32_t rs2_hi = RS2 >> 32;
160 
161     uint32_t r_lo = (rs1_hi ^ rs2_lo);
162     uint32_t r_hi = (rs1_hi ^ rs2_lo ^ rs2_hi);
163     target_ulong result = ((uint64_t)r_hi << 32) | r_lo;
164 
165     return result;
166 }
167 
168 target_ulong HELPER(aes64ks1i)(target_ulong rs1, target_ulong rnum)
169 {
170     uint64_t RS1 = rs1;
171     static const uint8_t round_consts[10] = {
172         0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36
173     };
174 
175     uint8_t enc_rnum = rnum;
176     uint32_t temp = (RS1 >> 32) & 0xFFFFFFFF;
177     uint8_t rcon_ = 0;
178     target_ulong result;
179 
180     if (enc_rnum != 0xA) {
181         temp = ror32(temp, 8); /* Rotate right by 8 */
182         rcon_ = round_consts[enc_rnum];
183     }
184 
185     temp = ((uint32_t)AES_sbox[(temp >> 24) & 0xFF] << 24) |
186            ((uint32_t)AES_sbox[(temp >> 16) & 0xFF] << 16) |
187            ((uint32_t)AES_sbox[(temp >> 8) & 0xFF] << 8) |
188            ((uint32_t)AES_sbox[(temp >> 0) & 0xFF] << 0);
189 
190     temp ^= rcon_;
191 
192     result = ((uint64_t)temp << 32) | temp;
193 
194     return result;
195 }
196 
197 target_ulong HELPER(aes64im)(target_ulong rs1)
198 {
199     AESState t;
200 
201     t.d[HOST_BIG_ENDIAN] = rs1;
202     t.d[!HOST_BIG_ENDIAN] = 0;
203     aesdec_IMC(&t, &t, false);
204     return t.d[HOST_BIG_ENDIAN];
205 }
206 
207 target_ulong HELPER(sm4ed)(target_ulong rs1, target_ulong rs2,
208                            target_ulong shamt)
209 {
210     uint32_t sb_in = (uint8_t)(rs2 >> shamt);
211     uint32_t sb_out = (uint32_t)sm4_sbox[sb_in];
212 
213     uint32_t x = sb_out ^ (sb_out << 8) ^ (sb_out << 2) ^ (sb_out << 18) ^
214                  ((sb_out & 0x3f) << 26) ^ ((sb_out & 0xC0) << 10);
215 
216     uint32_t rotl = rol32(x, shamt);
217 
218     return sext32_xlen(rotl ^ (uint32_t)rs1);
219 }
220 
221 target_ulong HELPER(sm4ks)(target_ulong rs1, target_ulong rs2,
222                            target_ulong shamt)
223 {
224     uint32_t sb_in = (uint8_t)(rs2 >> shamt);
225     uint32_t sb_out = sm4_sbox[sb_in];
226 
227     uint32_t x = sb_out ^ ((sb_out & 0x07) << 29) ^ ((sb_out & 0xFE) << 7) ^
228                  ((sb_out & 0x01) << 23) ^ ((sb_out & 0xF8) << 13);
229 
230     uint32_t rotl = rol32(x, shamt);
231 
232     return sext32_xlen(rotl ^ (uint32_t)rs1);
233 }
234 #undef sext32_xlen
235