xref: /freebsd/crypto/openssl/engines/e_padlock.c (revision 54b955f4df5e76b5679ba7f3eb6bb2d5fc62923d)
1 /*
2  * Copyright 2004-2023 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #include <stdio.h>
11 #include <string.h>
12 
13 #include <openssl/opensslconf.h>
14 #include <openssl/crypto.h>
15 #include <openssl/engine.h>
16 #include <openssl/evp.h>
17 #include <openssl/aes.h>
18 #include <openssl/rand.h>
19 #include <openssl/err.h>
20 #include <openssl/modes.h>
21 
22 #ifndef OPENSSL_NO_HW
23 # ifndef OPENSSL_NO_HW_PADLOCK
24 
25 /* Attempt to have a single source for both 0.9.7 and 0.9.8 :-) */
26 #  if (OPENSSL_VERSION_NUMBER >= 0x00908000L)
27 #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
28 #    define DYNAMIC_ENGINE
29 #   endif
30 #  elif (OPENSSL_VERSION_NUMBER >= 0x00907000L)
31 #   ifdef ENGINE_DYNAMIC_SUPPORT
32 #    define DYNAMIC_ENGINE
33 #   endif
34 #  else
35 #   error "Only OpenSSL >= 0.9.7 is supported"
36 #  endif
37 
38 /*
39  * VIA PadLock AES is available *ONLY* on some x86 CPUs. Not only that it
40  * doesn't exist elsewhere, but it even can't be compiled on other platforms!
41  */
42 
43 #  undef COMPILE_HW_PADLOCK
44 #  if defined(PADLOCK_ASM)
45 #   define COMPILE_HW_PADLOCK
46 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
47 static ENGINE *ENGINE_padlock(void);
48 #   endif
49 #  endif
50 
51 #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
52 void engine_load_padlock_int(void);
53 void engine_load_padlock_int(void)
54 {
55 /* On non-x86 CPUs it just returns. */
56 #   ifdef COMPILE_HW_PADLOCK
57     ENGINE *toadd = ENGINE_padlock();
58     if (!toadd)
59         return;
60     ENGINE_add(toadd);
61     ENGINE_free(toadd);
62     ERR_clear_error();
63 #   endif
64 }
65 
66 #  endif
67 
68 #  ifdef COMPILE_HW_PADLOCK
69 
70 /* Function for ENGINE detection and control */
71 static int padlock_available(void);
72 static int padlock_init(ENGINE *e);
73 
74 /* RNG Stuff */
75 static RAND_METHOD padlock_rand;
76 
77 /* Cipher Stuff */
78 static int padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
79                            const int **nids, int nid);
80 
81 /* Engine names */
82 static const char *padlock_id = "padlock";
83 static char padlock_name[100];
84 
85 /* Available features */
86 static int padlock_use_ace = 0; /* Advanced Cryptography Engine */
87 static int padlock_use_rng = 0; /* Random Number Generator */
88 
89 /* ===== Engine "management" functions ===== */
90 
91 /* Prepare the ENGINE structure for registration */
92 static int padlock_bind_helper(ENGINE *e)
93 {
94     /* Check available features */
95     padlock_available();
96 
97     /*
98      * RNG is currently disabled for reasons discussed in commentary just
99      * before padlock_rand_bytes function.
100      */
101     padlock_use_rng = 0;
102 
103     /* Generate a nice engine name with available features */
104     BIO_snprintf(padlock_name, sizeof(padlock_name),
105                  "VIA PadLock (%s, %s)",
106                  padlock_use_rng ? "RNG" : "no-RNG",
107                  padlock_use_ace ? "ACE" : "no-ACE");
108 
109     /* Register everything or return with an error */
110     if (!ENGINE_set_id(e, padlock_id) ||
111         !ENGINE_set_name(e, padlock_name) ||
112         !ENGINE_set_init_function(e, padlock_init) ||
113         (padlock_use_ace && !ENGINE_set_ciphers(e, padlock_ciphers)) ||
114         (padlock_use_rng && !ENGINE_set_RAND(e, &padlock_rand))) {
115         return 0;
116     }
117 
118     /* Everything looks good */
119     return 1;
120 }
121 
122 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
123 /* Constructor */
124 static ENGINE *ENGINE_padlock(void)
125 {
126     ENGINE *eng = ENGINE_new();
127 
128     if (eng == NULL) {
129         return NULL;
130     }
131 
132     if (!padlock_bind_helper(eng)) {
133         ENGINE_free(eng);
134         return NULL;
135     }
136 
137     return eng;
138 }
139 #   endif
140 
141 /* Check availability of the engine */
142 static int padlock_init(ENGINE *e)
143 {
144     return (padlock_use_rng || padlock_use_ace);
145 }
146 
147 #  ifndef AES_ASM
148 static int padlock_aes_set_encrypt_key(const unsigned char *userKey,
149                                        const int bits,
150                                        AES_KEY *key);
151 static int padlock_aes_set_decrypt_key(const unsigned char *userKey,
152                                        const int bits,
153                                        AES_KEY *key);
154 #   define AES_ASM
155 #   define AES_set_encrypt_key padlock_aes_set_encrypt_key
156 #   define AES_set_decrypt_key padlock_aes_set_decrypt_key
157 #   include "../crypto/aes/aes_core.c"
158 #  endif
159 
160 /*
161  * This stuff is needed if this ENGINE is being compiled into a
162  * self-contained shared-library.
163  */
164 #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
165 static int padlock_bind_fn(ENGINE *e, const char *id)
166 {
167     if (id && (strcmp(id, padlock_id) != 0)) {
168         return 0;
169     }
170 
171     if (!padlock_bind_helper(e)) {
172         return 0;
173     }
174 
175     return 1;
176 }
177 
178 IMPLEMENT_DYNAMIC_CHECK_FN()
179 IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
180 #   endif                       /* !OPENSSL_NO_DYNAMIC_ENGINE */
181 /* ===== Here comes the "real" engine ===== */
182 
183 /* Some AES-related constants */
184 #   define AES_BLOCK_SIZE          16
185 #   define AES_KEY_SIZE_128        16
186 #   define AES_KEY_SIZE_192        24
187 #   define AES_KEY_SIZE_256        32
188     /*
189      * Here we store the status information relevant to the current context.
190      */
191     /*
192      * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
193      * the order of items in this structure.  Don't blindly modify, reorder,
194      * etc!
195      */
196 struct padlock_cipher_data {
197     unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
198     union {
199         unsigned int pad[4];
200         struct {
201             int rounds:4;
202             int dgst:1;         /* n/a in C3 */
203             int align:1;        /* n/a in C3 */
204             int ciphr:1;        /* n/a in C3 */
205             unsigned int keygen:1;
206             int interm:1;
207             unsigned int encdec:1;
208             int ksize:2;
209         } b;
210     } cword;                    /* Control word */
211     AES_KEY ks;                 /* Encryption key */
212 };
213 
214 /* Interface to assembler module */
215 unsigned int padlock_capability(void);
216 void padlock_key_bswap(AES_KEY *key);
217 void padlock_verify_context(struct padlock_cipher_data *ctx);
218 void padlock_reload_key(void);
219 void padlock_aes_block(void *out, const void *inp,
220                        struct padlock_cipher_data *ctx);
221 int padlock_ecb_encrypt(void *out, const void *inp,
222                         struct padlock_cipher_data *ctx, size_t len);
223 int padlock_cbc_encrypt(void *out, const void *inp,
224                         struct padlock_cipher_data *ctx, size_t len);
225 int padlock_cfb_encrypt(void *out, const void *inp,
226                         struct padlock_cipher_data *ctx, size_t len);
227 int padlock_ofb_encrypt(void *out, const void *inp,
228                         struct padlock_cipher_data *ctx, size_t len);
229 int padlock_ctr32_encrypt(void *out, const void *inp,
230                           struct padlock_cipher_data *ctx, size_t len);
231 int padlock_xstore(void *out, int edx);
232 void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
233 void padlock_sha1(void *ctx, const void *inp, size_t len);
234 void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
235 void padlock_sha256(void *ctx, const void *inp, size_t len);
236 
237 /*
238  * Load supported features of the CPU to see if the PadLock is available.
239  */
240 static int padlock_available(void)
241 {
242     unsigned int edx = padlock_capability();
243 
244     /* Fill up some flags */
245     padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
246     padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
247 
248     return padlock_use_ace + padlock_use_rng;
249 }
250 
251 /* ===== AES encryption/decryption ===== */
252 
253 #   if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
254 #    define NID_aes_128_cfb NID_aes_128_cfb128
255 #   endif
256 
257 #   if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
258 #    define NID_aes_128_ofb NID_aes_128_ofb128
259 #   endif
260 
261 #   if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
262 #    define NID_aes_192_cfb NID_aes_192_cfb128
263 #   endif
264 
265 #   if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
266 #    define NID_aes_192_ofb NID_aes_192_ofb128
267 #   endif
268 
269 #   if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
270 #    define NID_aes_256_cfb NID_aes_256_cfb128
271 #   endif
272 
273 #   if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
274 #    define NID_aes_256_ofb NID_aes_256_ofb128
275 #   endif
276 
277 /* List of supported ciphers. */
278 static const int padlock_cipher_nids[] = {
279     NID_aes_128_ecb,
280     NID_aes_128_cbc,
281     NID_aes_128_cfb,
282     NID_aes_128_ofb,
283     NID_aes_128_ctr,
284 
285     NID_aes_192_ecb,
286     NID_aes_192_cbc,
287     NID_aes_192_cfb,
288     NID_aes_192_ofb,
289     NID_aes_192_ctr,
290 
291     NID_aes_256_ecb,
292     NID_aes_256_cbc,
293     NID_aes_256_cfb,
294     NID_aes_256_ofb,
295     NID_aes_256_ctr
296 };
297 
298 static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
299                                       sizeof(padlock_cipher_nids[0]));
300 
301 /* Function prototypes ... */
302 static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
303                                 const unsigned char *iv, int enc);
304 
305 #   define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
306         ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
307 #   define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
308         NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
309 
310 static int
311 padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
312                    const unsigned char *in_arg, size_t nbytes)
313 {
314     return padlock_ecb_encrypt(out_arg, in_arg,
315                                ALIGNED_CIPHER_DATA(ctx), nbytes);
316 }
317 
318 static int
319 padlock_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
320                    const unsigned char *in_arg, size_t nbytes)
321 {
322     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
323     int ret;
324 
325     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
326     if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
327         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
328     return ret;
329 }
330 
331 static int
332 padlock_cfb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
333                    const unsigned char *in_arg, size_t nbytes)
334 {
335     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
336     size_t chunk;
337 
338     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
339         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
340 
341         if (chunk >= AES_BLOCK_SIZE)
342             return 0;           /* bogus value */
343 
344         if (EVP_CIPHER_CTX_encrypting(ctx))
345             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
346                 ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
347                 chunk++, nbytes--;
348         } else
349             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
350                 unsigned char c = *(in_arg++);
351                 *(out_arg++) = c ^ ivp[chunk];
352                 ivp[chunk++] = c, nbytes--;
353             }
354 
355         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
356     }
357 
358     if (nbytes == 0)
359         return 1;
360 
361     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
362 
363     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
364         if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
365             return 0;
366         nbytes -= chunk;
367     }
368 
369     if (nbytes) {
370         unsigned char *ivp = cdata->iv;
371 
372         out_arg += chunk;
373         in_arg += chunk;
374         EVP_CIPHER_CTX_set_num(ctx, nbytes);
375         if (cdata->cword.b.encdec) {
376             cdata->cword.b.encdec = 0;
377             padlock_reload_key();
378             padlock_aes_block(ivp, ivp, cdata);
379             cdata->cword.b.encdec = 1;
380             padlock_reload_key();
381             while (nbytes) {
382                 unsigned char c = *(in_arg++);
383                 *(out_arg++) = c ^ *ivp;
384                 *(ivp++) = c, nbytes--;
385             }
386         } else {
387             padlock_reload_key();
388             padlock_aes_block(ivp, ivp, cdata);
389             padlock_reload_key();
390             while (nbytes) {
391                 *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
392                 ivp++, nbytes--;
393             }
394         }
395     }
396 
397     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
398 
399     return 1;
400 }
401 
402 static int
403 padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
404                    const unsigned char *in_arg, size_t nbytes)
405 {
406     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
407     size_t chunk;
408 
409     /*
410      * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
411      */
412     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
413         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
414 
415         if (chunk >= AES_BLOCK_SIZE)
416             return 0;           /* bogus value */
417 
418         while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
419             *(out_arg++) = *(in_arg++) ^ ivp[chunk];
420             chunk++, nbytes--;
421         }
422 
423         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
424     }
425 
426     if (nbytes == 0)
427         return 1;
428 
429     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
430 
431     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
432         if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
433             return 0;
434         nbytes -= chunk;
435     }
436 
437     if (nbytes) {
438         unsigned char *ivp = cdata->iv;
439 
440         out_arg += chunk;
441         in_arg += chunk;
442         EVP_CIPHER_CTX_set_num(ctx, nbytes);
443         padlock_reload_key();   /* empirically found */
444         padlock_aes_block(ivp, ivp, cdata);
445         padlock_reload_key();   /* empirically found */
446         while (nbytes) {
447             *(out_arg++) = *(in_arg++) ^ *ivp;
448             ivp++, nbytes--;
449         }
450     }
451 
452     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
453 
454     return 1;
455 }
456 
457 static void padlock_ctr32_encrypt_glue(const unsigned char *in,
458                                        unsigned char *out, size_t blocks,
459                                        struct padlock_cipher_data *ctx,
460                                        const unsigned char *ivec)
461 {
462     memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
463     padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
464 }
465 
466 static int
467 padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
468                    const unsigned char *in_arg, size_t nbytes)
469 {
470     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
471     unsigned int num = EVP_CIPHER_CTX_num(ctx);
472 
473     CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
474                                 cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
475                                 EVP_CIPHER_CTX_buf_noconst(ctx), &num,
476                                 (ctr128_f) padlock_ctr32_encrypt_glue);
477 
478     EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
479     return 1;
480 }
481 
482 #   define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
483 #   define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
484 #   define EVP_CIPHER_block_size_OFB       1
485 #   define EVP_CIPHER_block_size_CFB       1
486 #   define EVP_CIPHER_block_size_CTR       1
487 
488 /*
489  * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
490  * of preprocessor magic :-)
491  */
492 #   define DECLARE_AES_EVP(ksize,lmode,umode)      \
493 static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
494 static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
495 {                                                                       \
496     if (_hidden_aes_##ksize##_##lmode == NULL                           \
497         && ((_hidden_aes_##ksize##_##lmode =                            \
498              EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
499                                  EVP_CIPHER_block_size_##umode,         \
500                                  AES_KEY_SIZE_##ksize)) == NULL         \
501             || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
502                                               AES_BLOCK_SIZE)           \
503             || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
504                                           0 | EVP_CIPH_##umode##_MODE)  \
505             || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
506                                          padlock_aes_init_key)          \
507             || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
508                                               padlock_##lmode##_cipher) \
509             || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
510                                                   sizeof(struct padlock_cipher_data) + 16) \
511             || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
512                                                     EVP_CIPHER_set_asn1_iv) \
513             || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
514                                                     EVP_CIPHER_get_asn1_iv))) { \
515         EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
516         _hidden_aes_##ksize##_##lmode = NULL;                           \
517     }                                                                   \
518     return _hidden_aes_##ksize##_##lmode;                               \
519 }
520 
521 DECLARE_AES_EVP(128, ecb, ECB)
522 DECLARE_AES_EVP(128, cbc, CBC)
523 DECLARE_AES_EVP(128, cfb, CFB)
524 DECLARE_AES_EVP(128, ofb, OFB)
525 DECLARE_AES_EVP(128, ctr, CTR)
526 
527 DECLARE_AES_EVP(192, ecb, ECB)
528 DECLARE_AES_EVP(192, cbc, CBC)
529 DECLARE_AES_EVP(192, cfb, CFB)
530 DECLARE_AES_EVP(192, ofb, OFB)
531 DECLARE_AES_EVP(192, ctr, CTR)
532 
533 DECLARE_AES_EVP(256, ecb, ECB)
534 DECLARE_AES_EVP(256, cbc, CBC)
535 DECLARE_AES_EVP(256, cfb, CFB)
536 DECLARE_AES_EVP(256, ofb, OFB)
537 DECLARE_AES_EVP(256, ctr, CTR)
538 
539 static int
540 padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
541                 int nid)
542 {
543     /* No specific cipher => return a list of supported nids ... */
544     if (!cipher) {
545         *nids = padlock_cipher_nids;
546         return padlock_cipher_nids_num;
547     }
548 
549     /* ... or the requested "cipher" otherwise */
550     switch (nid) {
551     case NID_aes_128_ecb:
552         *cipher = padlock_aes_128_ecb();
553         break;
554     case NID_aes_128_cbc:
555         *cipher = padlock_aes_128_cbc();
556         break;
557     case NID_aes_128_cfb:
558         *cipher = padlock_aes_128_cfb();
559         break;
560     case NID_aes_128_ofb:
561         *cipher = padlock_aes_128_ofb();
562         break;
563     case NID_aes_128_ctr:
564         *cipher = padlock_aes_128_ctr();
565         break;
566 
567     case NID_aes_192_ecb:
568         *cipher = padlock_aes_192_ecb();
569         break;
570     case NID_aes_192_cbc:
571         *cipher = padlock_aes_192_cbc();
572         break;
573     case NID_aes_192_cfb:
574         *cipher = padlock_aes_192_cfb();
575         break;
576     case NID_aes_192_ofb:
577         *cipher = padlock_aes_192_ofb();
578         break;
579     case NID_aes_192_ctr:
580         *cipher = padlock_aes_192_ctr();
581         break;
582 
583     case NID_aes_256_ecb:
584         *cipher = padlock_aes_256_ecb();
585         break;
586     case NID_aes_256_cbc:
587         *cipher = padlock_aes_256_cbc();
588         break;
589     case NID_aes_256_cfb:
590         *cipher = padlock_aes_256_cfb();
591         break;
592     case NID_aes_256_ofb:
593         *cipher = padlock_aes_256_ofb();
594         break;
595     case NID_aes_256_ctr:
596         *cipher = padlock_aes_256_ctr();
597         break;
598 
599     default:
600         /* Sorry, we don't support this NID */
601         *cipher = NULL;
602         return 0;
603     }
604 
605     return 1;
606 }
607 
608 /* Prepare the encryption key for PadLock usage */
609 static int
610 padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
611                      const unsigned char *iv, int enc)
612 {
613     struct padlock_cipher_data *cdata;
614     int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
615     unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
616 
617     if (key == NULL)
618         return 0;               /* ERROR */
619 
620     cdata = ALIGNED_CIPHER_DATA(ctx);
621     memset(cdata, 0, sizeof(*cdata));
622 
623     /* Prepare Control word. */
624     if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
625         cdata->cword.b.encdec = 0;
626     else
627         cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
628     cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
629     cdata->cword.b.ksize = (key_len - 128) / 64;
630 
631     switch (key_len) {
632     case 128:
633         /*
634          * PadLock can generate an extended key for AES128 in hardware
635          */
636         memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
637         cdata->cword.b.keygen = 0;
638         break;
639 
640     case 192:
641     case 256:
642         /*
643          * Generate an extended AES key in software. Needed for AES192/AES256
644          */
645         /*
646          * Well, the above applies to Stepping 8 CPUs and is listed as
647          * hardware errata. They most likely will fix it at some point and
648          * then a check for stepping would be due here.
649          */
650         if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
651             && !enc)
652             AES_set_decrypt_key(key, key_len, &cdata->ks);
653         else
654             AES_set_encrypt_key(key, key_len, &cdata->ks);
655         /*
656          * OpenSSL C functions use byte-swapped extended key.
657          */
658         padlock_key_bswap(&cdata->ks);
659         cdata->cword.b.keygen = 1;
660         break;
661 
662     default:
663         /* ERROR */
664         return 0;
665     }
666 
667     /*
668      * This is done to cover for cases when user reuses the
669      * context for new key. The catch is that if we don't do
670      * this, padlock_eas_cipher might proceed with old key...
671      */
672     padlock_reload_key();
673 
674     return 1;
675 }
676 
677 /* ===== Random Number Generator ===== */
678 /*
679  * This code is not engaged. The reason is that it does not comply
680  * with recommendations for VIA RNG usage for secure applications
681  * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
682  * provide meaningful error control...
683  */
684 /*
685  * Wrapper that provides an interface between the API and the raw PadLock
686  * RNG
687  */
688 static int padlock_rand_bytes(unsigned char *output, int count)
689 {
690     unsigned int eax, buf;
691 
692     while (count >= 8) {
693         eax = padlock_xstore(output, 0);
694         if (!(eax & (1 << 6)))
695             return 0;           /* RNG disabled */
696         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
697         if (eax & (0x1F << 10))
698             return 0;
699         if ((eax & 0x1F) == 0)
700             continue;           /* no data, retry... */
701         if ((eax & 0x1F) != 8)
702             return 0;           /* fatal failure...  */
703         output += 8;
704         count -= 8;
705     }
706     while (count > 0) {
707         eax = padlock_xstore(&buf, 3);
708         if (!(eax & (1 << 6)))
709             return 0;           /* RNG disabled */
710         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
711         if (eax & (0x1F << 10))
712             return 0;
713         if ((eax & 0x1F) == 0)
714             continue;           /* no data, retry... */
715         if ((eax & 0x1F) != 1)
716             return 0;           /* fatal failure...  */
717         *output++ = (unsigned char)buf;
718         count--;
719     }
720     OPENSSL_cleanse(&buf, sizeof(buf));
721 
722     return 1;
723 }
724 
725 /* Dummy but necessary function */
726 static int padlock_rand_status(void)
727 {
728     return 1;
729 }
730 
731 /* Prepare structure for registration */
732 static RAND_METHOD padlock_rand = {
733     NULL,                       /* seed */
734     padlock_rand_bytes,         /* bytes */
735     NULL,                       /* cleanup */
736     NULL,                       /* add */
737     padlock_rand_bytes,         /* pseudorand */
738     padlock_rand_status,        /* rand status */
739 };
740 
741 #  endif                        /* COMPILE_HW_PADLOCK */
742 # endif                         /* !OPENSSL_NO_HW_PADLOCK */
743 #endif                          /* !OPENSSL_NO_HW */
744 
745 #if defined(OPENSSL_NO_HW) || defined(OPENSSL_NO_HW_PADLOCK) \
746         || !defined(COMPILE_HW_PADLOCK)
747 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
748 OPENSSL_EXPORT
749     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
750 OPENSSL_EXPORT
751     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
752 {
753     return 0;
754 }
755 
756 IMPLEMENT_DYNAMIC_CHECK_FN()
757 # endif
758 #endif
759