xref: /qemu/target/s390x/tcg/crypto_helper.c (revision a976a99a)
1 /*
2  *  s390x crypto helpers
3  *
4  *  Copyright (C) 2022 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
5  *  Copyright (c) 2017 Red Hat Inc
6  *
7  *  Authors:
8  *   David Hildenbrand <david@redhat.com>
9  *   Jason A. Donenfeld <Jason@zx2c4.com>
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or later.
12  * See the COPYING file in the top-level directory.
13  */
14 
15 #include "qemu/osdep.h"
16 #include "qemu/main-loop.h"
17 #include "qemu/guest-random.h"
18 #include "s390x-internal.h"
19 #include "tcg_s390x.h"
20 #include "exec/helper-proto.h"
21 #include "exec/exec-all.h"
22 #include "exec/cpu_ldst.h"
23 
24 static uint64_t R(uint64_t x, int c)
25 {
26     return (x >> c) | (x << (64 - c));
27 }
28 static uint64_t Ch(uint64_t x, uint64_t y, uint64_t z)
29 {
30     return (x & y) ^ (~x & z);
31 }
32 static uint64_t Maj(uint64_t x, uint64_t y, uint64_t z)
33 {
34     return (x & y) ^ (x & z) ^ (y & z);
35 }
36 static uint64_t Sigma0(uint64_t x)
37 {
38     return R(x, 28) ^ R(x, 34) ^ R(x, 39);
39 }
40 static uint64_t Sigma1(uint64_t x)
41 {
42     return R(x, 14) ^ R(x, 18) ^ R(x, 41);
43 }
44 static uint64_t sigma0(uint64_t x)
45 {
46     return R(x, 1) ^ R(x, 8) ^ (x >> 7);
47 }
48 static uint64_t sigma1(uint64_t x)
49 {
50     return R(x, 19) ^ R(x, 61) ^ (x >> 6);
51 }
52 
53 static const uint64_t K[80] = {
54     0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL,
55     0xe9b5dba58189dbbcULL, 0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL,
56     0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL, 0xd807aa98a3030242ULL,
57     0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL,
58     0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL,
59     0xc19bf174cf692694ULL, 0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL,
60     0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL, 0x2de92c6f592b0275ULL,
61     0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,
62     0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL,
63     0xbf597fc7beef0ee4ULL, 0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL,
64     0x06ca6351e003826fULL, 0x142929670a0e6e70ULL, 0x27b70a8546d22ffcULL,
65     0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL,
66     0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL,
67     0x92722c851482353bULL, 0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL,
68     0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL, 0xd192e819d6ef5218ULL,
69     0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,
70     0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL,
71     0x34b0bcb5e19b48a8ULL, 0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL,
72     0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL, 0x748f82ee5defb2fcULL,
73     0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL,
74     0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL,
75     0xc67178f2e372532bULL, 0xca273eceea26619cULL, 0xd186b8c721c0c207ULL,
76     0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL, 0x06f067aa72176fbaULL,
77     0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL,
78     0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL,
79     0x431d67c49c100d4cULL, 0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL,
80     0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL
81 };
82 
83 /* a is icv/ocv, w is a single message block. w will get reused internally. */
84 static void sha512_bda(uint64_t a[8], uint64_t w[16])
85 {
86     uint64_t t, z[8], b[8];
87     int i, j;
88 
89     memcpy(z, a, sizeof(z));
90     for (i = 0; i < 80; i++) {
91         memcpy(b, a, sizeof(b));
92 
93         t = a[7] + Sigma1(a[4]) + Ch(a[4], a[5], a[6]) + K[i] + w[i % 16];
94         b[7] = t + Sigma0(a[0]) + Maj(a[0], a[1], a[2]);
95         b[3] += t;
96         for (j = 0; j < 8; ++j) {
97             a[(j + 1) % 8] = b[j];
98         }
99         if (i % 16 == 15) {
100             for (j = 0; j < 16; ++j) {
101                 w[j] += w[(j + 9) % 16] + sigma0(w[(j + 1) % 16]) +
102                         sigma1(w[(j + 14) % 16]);
103             }
104         }
105     }
106 
107     for (i = 0; i < 8; i++) {
108         a[i] += z[i];
109     }
110 }
111 
112 /* a is icv/ocv, w is a single message block that needs be64 conversion. */
113 static void sha512_bda_be64(uint64_t a[8], uint64_t w[16])
114 {
115     uint64_t t[16];
116     int i;
117 
118     for (i = 0; i < 16; i++) {
119         t[i] = be64_to_cpu(w[i]);
120     }
121     sha512_bda(a, t);
122 }
123 
124 static void sha512_read_icv(CPUS390XState *env, uint64_t addr,
125                             uint64_t a[8], uintptr_t ra)
126 {
127     int i;
128 
129     for (i = 0; i < 8; i++, addr += 8) {
130         addr = wrap_address(env, addr);
131         a[i] = cpu_ldq_be_data_ra(env, addr, ra);
132     }
133 }
134 
135 static void sha512_write_ocv(CPUS390XState *env, uint64_t addr,
136                              uint64_t a[8], uintptr_t ra)
137 {
138     int i;
139 
140     for (i = 0; i < 8; i++, addr += 8) {
141         addr = wrap_address(env, addr);
142         cpu_stq_be_data_ra(env, addr, a[i], ra);
143     }
144 }
145 
146 static void sha512_read_block(CPUS390XState *env, uint64_t addr,
147                               uint64_t a[16], uintptr_t ra)
148 {
149     int i;
150 
151     for (i = 0; i < 16; i++, addr += 8) {
152         addr = wrap_address(env, addr);
153         a[i] = cpu_ldq_be_data_ra(env, addr, ra);
154     }
155 }
156 
157 static void sha512_read_mbl_be64(CPUS390XState *env, uint64_t addr,
158                                  uint8_t a[16], uintptr_t ra)
159 {
160     int i;
161 
162     for (i = 0; i < 16; i++, addr += 1) {
163         addr = wrap_address(env, addr);
164         a[i] = cpu_ldub_data_ra(env, addr, ra);
165     }
166 }
167 
168 static int cpacf_sha512(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
169                       uint64_t *message_reg, uint64_t *len_reg, uint32_t type)
170 {
171     enum { MAX_BLOCKS_PER_RUN = 64 }; /* Arbitrary: keep interactivity. */
172     uint64_t len = *len_reg, a[8], processed = 0;
173     int i, message_reg_len = 64;
174 
175     g_assert(type == S390_FEAT_TYPE_KIMD || type == S390_FEAT_TYPE_KLMD);
176 
177     if (!(env->psw.mask & PSW_MASK_64)) {
178         len = (uint32_t)len;
179         message_reg_len = (env->psw.mask & PSW_MASK_32) ? 32 : 24;
180     }
181 
182     /* KIMD: length has to be properly aligned. */
183     if (type == S390_FEAT_TYPE_KIMD && !QEMU_IS_ALIGNED(len, 128)) {
184         tcg_s390_program_interrupt(env, PGM_SPECIFICATION, ra);
185     }
186 
187     sha512_read_icv(env, param_addr, a, ra);
188 
189     /* Process full blocks first. */
190     for (; len >= 128; len -= 128, processed += 128) {
191         uint64_t w[16];
192 
193         if (processed >= MAX_BLOCKS_PER_RUN * 128) {
194             break;
195         }
196 
197         sha512_read_block(env, *message_reg + processed, w, ra);
198         sha512_bda(a, w);
199     }
200 
201     /* KLMD: Process partial/empty block last. */
202     if (type == S390_FEAT_TYPE_KLMD && len < 128) {
203         uint8_t x[128];
204 
205         /* Read the remainder of the message byte-per-byte. */
206         for (i = 0; i < len; i++) {
207             uint64_t addr = wrap_address(env, *message_reg + processed + i);
208 
209             x[i] = cpu_ldub_data_ra(env, addr, ra);
210         }
211         /* Pad the remainder with zero and set the top bit. */
212         memset(x + len, 0, 128 - len);
213         x[len] = 128;
214 
215         /*
216          * Place the MBL either into this block (if there is space left),
217          * or use an additional one.
218          */
219         if (len < 112) {
220             sha512_read_mbl_be64(env, param_addr + 64, x + 112, ra);
221         }
222         sha512_bda_be64(a, (uint64_t *)x);
223 
224         if (len >= 112) {
225             memset(x, 0, 112);
226             sha512_read_mbl_be64(env, param_addr + 64, x + 112, ra);
227             sha512_bda_be64(a, (uint64_t *)x);
228         }
229 
230         processed += len;
231         len = 0;
232     }
233 
234     /*
235      * Modify memory after we read all inputs and modify registers only after
236      * writing memory succeeded.
237      *
238      * TODO: if writing fails halfway through (e.g., when crossing page
239      * boundaries), we're in trouble. We'd need something like access_prepare().
240      */
241     sha512_write_ocv(env, param_addr, a, ra);
242     *message_reg = deposit64(*message_reg, 0, message_reg_len,
243                              *message_reg + processed);
244     *len_reg -= processed;
245     return !len ? 0 : 3;
246 }
247 
248 static void fill_buf_random(CPUS390XState *env, uintptr_t ra,
249                             uint64_t *buf_reg, uint64_t *len_reg)
250 {
251     uint8_t tmp[256];
252     uint64_t len = *len_reg;
253     int buf_reg_len = 64;
254 
255     if (!(env->psw.mask & PSW_MASK_64)) {
256         len = (uint32_t)len;
257         buf_reg_len = (env->psw.mask & PSW_MASK_32) ? 32 : 24;
258     }
259 
260     while (len) {
261         size_t block = MIN(len, sizeof(tmp));
262 
263         qemu_guest_getrandom_nofail(tmp, block);
264         for (size_t i = 0; i < block; ++i) {
265             cpu_stb_data_ra(env, wrap_address(env, *buf_reg), tmp[i], ra);
266             *buf_reg = deposit64(*buf_reg, 0, buf_reg_len, *buf_reg + 1);
267             --*len_reg;
268         }
269         len -= block;
270     }
271 }
272 
273 uint32_t HELPER(msa)(CPUS390XState *env, uint32_t r1, uint32_t r2, uint32_t r3,
274                      uint32_t type)
275 {
276     const uintptr_t ra = GETPC();
277     const uint8_t mod = env->regs[0] & 0x80ULL;
278     const uint8_t fc = env->regs[0] & 0x7fULL;
279     uint8_t subfunc[16] = { 0 };
280     uint64_t param_addr;
281     int i;
282 
283     switch (type) {
284     case S390_FEAT_TYPE_KMAC:
285     case S390_FEAT_TYPE_KIMD:
286     case S390_FEAT_TYPE_KLMD:
287     case S390_FEAT_TYPE_PCKMO:
288     case S390_FEAT_TYPE_PCC:
289         if (mod) {
290             tcg_s390_program_interrupt(env, PGM_SPECIFICATION, ra);
291         }
292         break;
293     }
294 
295     s390_get_feat_block(type, subfunc);
296     if (!test_be_bit(fc, subfunc)) {
297         tcg_s390_program_interrupt(env, PGM_SPECIFICATION, ra);
298     }
299 
300     switch (fc) {
301     case 0: /* query subfunction */
302         for (i = 0; i < 16; i++) {
303             param_addr = wrap_address(env, env->regs[1] + i);
304             cpu_stb_data_ra(env, param_addr, subfunc[i], ra);
305         }
306         break;
307     case 3: /* CPACF_*_SHA_512 */
308         return cpacf_sha512(env, ra, env->regs[1], &env->regs[r2],
309                             &env->regs[r2 + 1], type);
310     case 114: /* CPACF_PRNO_TRNG */
311         fill_buf_random(env, ra, &env->regs[r1], &env->regs[r1 + 1]);
312         fill_buf_random(env, ra, &env->regs[r2], &env->regs[r2 + 1]);
313         break;
314     default:
315         /* we don't implement any other subfunction yet */
316         g_assert_not_reached();
317     }
318 
319     return 0;
320 }
321