xref: /freebsd/crypto/openssl/engines/e_padlock.c (revision 6ba2210ee039f2f12878c217bcf058e9c8b26b29)
1 /*
2  * Copyright 2004-2019 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 /*
148  * This stuff is needed if this ENGINE is being compiled into a
149  * self-contained shared-library.
150  */
151 #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
152 static int padlock_bind_fn(ENGINE *e, const char *id)
153 {
154     if (id && (strcmp(id, padlock_id) != 0)) {
155         return 0;
156     }
157 
158     if (!padlock_bind_helper(e)) {
159         return 0;
160     }
161 
162     return 1;
163 }
164 
165 IMPLEMENT_DYNAMIC_CHECK_FN()
166 IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
167 #   endif                       /* !OPENSSL_NO_DYNAMIC_ENGINE */
168 /* ===== Here comes the "real" engine ===== */
169 
170 /* Some AES-related constants */
171 #   define AES_BLOCK_SIZE          16
172 #   define AES_KEY_SIZE_128        16
173 #   define AES_KEY_SIZE_192        24
174 #   define AES_KEY_SIZE_256        32
175     /*
176      * Here we store the status information relevant to the current context.
177      */
178     /*
179      * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
180      * the order of items in this structure.  Don't blindly modify, reorder,
181      * etc!
182      */
183 struct padlock_cipher_data {
184     unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
185     union {
186         unsigned int pad[4];
187         struct {
188             int rounds:4;
189             int dgst:1;         /* n/a in C3 */
190             int align:1;        /* n/a in C3 */
191             int ciphr:1;        /* n/a in C3 */
192             unsigned int keygen:1;
193             int interm:1;
194             unsigned int encdec:1;
195             int ksize:2;
196         } b;
197     } cword;                    /* Control word */
198     AES_KEY ks;                 /* Encryption key */
199 };
200 
201 /* Interface to assembler module */
202 unsigned int padlock_capability(void);
203 void padlock_key_bswap(AES_KEY *key);
204 void padlock_verify_context(struct padlock_cipher_data *ctx);
205 void padlock_reload_key(void);
206 void padlock_aes_block(void *out, const void *inp,
207                        struct padlock_cipher_data *ctx);
208 int padlock_ecb_encrypt(void *out, const void *inp,
209                         struct padlock_cipher_data *ctx, size_t len);
210 int padlock_cbc_encrypt(void *out, const void *inp,
211                         struct padlock_cipher_data *ctx, size_t len);
212 int padlock_cfb_encrypt(void *out, const void *inp,
213                         struct padlock_cipher_data *ctx, size_t len);
214 int padlock_ofb_encrypt(void *out, const void *inp,
215                         struct padlock_cipher_data *ctx, size_t len);
216 int padlock_ctr32_encrypt(void *out, const void *inp,
217                           struct padlock_cipher_data *ctx, size_t len);
218 int padlock_xstore(void *out, int edx);
219 void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
220 void padlock_sha1(void *ctx, const void *inp, size_t len);
221 void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
222 void padlock_sha256(void *ctx, const void *inp, size_t len);
223 
224 /*
225  * Load supported features of the CPU to see if the PadLock is available.
226  */
227 static int padlock_available(void)
228 {
229     unsigned int edx = padlock_capability();
230 
231     /* Fill up some flags */
232     padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
233     padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
234 
235     return padlock_use_ace + padlock_use_rng;
236 }
237 
238 /* ===== AES encryption/decryption ===== */
239 
240 #   if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
241 #    define NID_aes_128_cfb NID_aes_128_cfb128
242 #   endif
243 
244 #   if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
245 #    define NID_aes_128_ofb NID_aes_128_ofb128
246 #   endif
247 
248 #   if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
249 #    define NID_aes_192_cfb NID_aes_192_cfb128
250 #   endif
251 
252 #   if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
253 #    define NID_aes_192_ofb NID_aes_192_ofb128
254 #   endif
255 
256 #   if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
257 #    define NID_aes_256_cfb NID_aes_256_cfb128
258 #   endif
259 
260 #   if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
261 #    define NID_aes_256_ofb NID_aes_256_ofb128
262 #   endif
263 
264 /* List of supported ciphers. */
265 static const int padlock_cipher_nids[] = {
266     NID_aes_128_ecb,
267     NID_aes_128_cbc,
268     NID_aes_128_cfb,
269     NID_aes_128_ofb,
270     NID_aes_128_ctr,
271 
272     NID_aes_192_ecb,
273     NID_aes_192_cbc,
274     NID_aes_192_cfb,
275     NID_aes_192_ofb,
276     NID_aes_192_ctr,
277 
278     NID_aes_256_ecb,
279     NID_aes_256_cbc,
280     NID_aes_256_cfb,
281     NID_aes_256_ofb,
282     NID_aes_256_ctr
283 };
284 
285 static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
286                                       sizeof(padlock_cipher_nids[0]));
287 
288 /* Function prototypes ... */
289 static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
290                                 const unsigned char *iv, int enc);
291 
292 #   define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
293         ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
294 #   define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
295         NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
296 
297 static int
298 padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
299                    const unsigned char *in_arg, size_t nbytes)
300 {
301     return padlock_ecb_encrypt(out_arg, in_arg,
302                                ALIGNED_CIPHER_DATA(ctx), nbytes);
303 }
304 
305 static int
306 padlock_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
307                    const unsigned char *in_arg, size_t nbytes)
308 {
309     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
310     int ret;
311 
312     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
313     if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
314         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
315     return ret;
316 }
317 
318 static int
319 padlock_cfb_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     size_t chunk;
324 
325     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
326         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
327 
328         if (chunk >= AES_BLOCK_SIZE)
329             return 0;           /* bogus value */
330 
331         if (EVP_CIPHER_CTX_encrypting(ctx))
332             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
333                 ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
334                 chunk++, nbytes--;
335         } else
336             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
337                 unsigned char c = *(in_arg++);
338                 *(out_arg++) = c ^ ivp[chunk];
339                 ivp[chunk++] = c, nbytes--;
340             }
341 
342         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
343     }
344 
345     if (nbytes == 0)
346         return 1;
347 
348     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
349 
350     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
351         if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
352             return 0;
353         nbytes -= chunk;
354     }
355 
356     if (nbytes) {
357         unsigned char *ivp = cdata->iv;
358 
359         out_arg += chunk;
360         in_arg += chunk;
361         EVP_CIPHER_CTX_set_num(ctx, nbytes);
362         if (cdata->cword.b.encdec) {
363             cdata->cword.b.encdec = 0;
364             padlock_reload_key();
365             padlock_aes_block(ivp, ivp, cdata);
366             cdata->cword.b.encdec = 1;
367             padlock_reload_key();
368             while (nbytes) {
369                 unsigned char c = *(in_arg++);
370                 *(out_arg++) = c ^ *ivp;
371                 *(ivp++) = c, nbytes--;
372             }
373         } else {
374             padlock_reload_key();
375             padlock_aes_block(ivp, ivp, cdata);
376             padlock_reload_key();
377             while (nbytes) {
378                 *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
379                 ivp++, nbytes--;
380             }
381         }
382     }
383 
384     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
385 
386     return 1;
387 }
388 
389 static int
390 padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
391                    const unsigned char *in_arg, size_t nbytes)
392 {
393     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
394     size_t chunk;
395 
396     /*
397      * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
398      */
399     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
400         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
401 
402         if (chunk >= AES_BLOCK_SIZE)
403             return 0;           /* bogus value */
404 
405         while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
406             *(out_arg++) = *(in_arg++) ^ ivp[chunk];
407             chunk++, nbytes--;
408         }
409 
410         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
411     }
412 
413     if (nbytes == 0)
414         return 1;
415 
416     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
417 
418     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
419         if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
420             return 0;
421         nbytes -= chunk;
422     }
423 
424     if (nbytes) {
425         unsigned char *ivp = cdata->iv;
426 
427         out_arg += chunk;
428         in_arg += chunk;
429         EVP_CIPHER_CTX_set_num(ctx, nbytes);
430         padlock_reload_key();   /* empirically found */
431         padlock_aes_block(ivp, ivp, cdata);
432         padlock_reload_key();   /* empirically found */
433         while (nbytes) {
434             *(out_arg++) = *(in_arg++) ^ *ivp;
435             ivp++, nbytes--;
436         }
437     }
438 
439     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
440 
441     return 1;
442 }
443 
444 static void padlock_ctr32_encrypt_glue(const unsigned char *in,
445                                        unsigned char *out, size_t blocks,
446                                        struct padlock_cipher_data *ctx,
447                                        const unsigned char *ivec)
448 {
449     memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
450     padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
451 }
452 
453 static int
454 padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
455                    const unsigned char *in_arg, size_t nbytes)
456 {
457     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
458     unsigned int num = EVP_CIPHER_CTX_num(ctx);
459 
460     CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
461                                 cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
462                                 EVP_CIPHER_CTX_buf_noconst(ctx), &num,
463                                 (ctr128_f) padlock_ctr32_encrypt_glue);
464 
465     EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
466     return 1;
467 }
468 
469 #   define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
470 #   define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
471 #   define EVP_CIPHER_block_size_OFB       1
472 #   define EVP_CIPHER_block_size_CFB       1
473 #   define EVP_CIPHER_block_size_CTR       1
474 
475 /*
476  * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
477  * of preprocessor magic :-)
478  */
479 #   define DECLARE_AES_EVP(ksize,lmode,umode)      \
480 static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
481 static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
482 {                                                                       \
483     if (_hidden_aes_##ksize##_##lmode == NULL                           \
484         && ((_hidden_aes_##ksize##_##lmode =                            \
485              EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
486                                  EVP_CIPHER_block_size_##umode,         \
487                                  AES_KEY_SIZE_##ksize)) == NULL         \
488             || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
489                                               AES_BLOCK_SIZE)           \
490             || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
491                                           0 | EVP_CIPH_##umode##_MODE)  \
492             || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
493                                          padlock_aes_init_key)          \
494             || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
495                                               padlock_##lmode##_cipher) \
496             || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
497                                                   sizeof(struct padlock_cipher_data) + 16) \
498             || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
499                                                     EVP_CIPHER_set_asn1_iv) \
500             || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
501                                                     EVP_CIPHER_get_asn1_iv))) { \
502         EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
503         _hidden_aes_##ksize##_##lmode = NULL;                           \
504     }                                                                   \
505     return _hidden_aes_##ksize##_##lmode;                               \
506 }
507 
508 DECLARE_AES_EVP(128, ecb, ECB)
509 DECLARE_AES_EVP(128, cbc, CBC)
510 DECLARE_AES_EVP(128, cfb, CFB)
511 DECLARE_AES_EVP(128, ofb, OFB)
512 DECLARE_AES_EVP(128, ctr, CTR)
513 
514 DECLARE_AES_EVP(192, ecb, ECB)
515 DECLARE_AES_EVP(192, cbc, CBC)
516 DECLARE_AES_EVP(192, cfb, CFB)
517 DECLARE_AES_EVP(192, ofb, OFB)
518 DECLARE_AES_EVP(192, ctr, CTR)
519 
520 DECLARE_AES_EVP(256, ecb, ECB)
521 DECLARE_AES_EVP(256, cbc, CBC)
522 DECLARE_AES_EVP(256, cfb, CFB)
523 DECLARE_AES_EVP(256, ofb, OFB)
524 DECLARE_AES_EVP(256, ctr, CTR)
525 
526 static int
527 padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
528                 int nid)
529 {
530     /* No specific cipher => return a list of supported nids ... */
531     if (!cipher) {
532         *nids = padlock_cipher_nids;
533         return padlock_cipher_nids_num;
534     }
535 
536     /* ... or the requested "cipher" otherwise */
537     switch (nid) {
538     case NID_aes_128_ecb:
539         *cipher = padlock_aes_128_ecb();
540         break;
541     case NID_aes_128_cbc:
542         *cipher = padlock_aes_128_cbc();
543         break;
544     case NID_aes_128_cfb:
545         *cipher = padlock_aes_128_cfb();
546         break;
547     case NID_aes_128_ofb:
548         *cipher = padlock_aes_128_ofb();
549         break;
550     case NID_aes_128_ctr:
551         *cipher = padlock_aes_128_ctr();
552         break;
553 
554     case NID_aes_192_ecb:
555         *cipher = padlock_aes_192_ecb();
556         break;
557     case NID_aes_192_cbc:
558         *cipher = padlock_aes_192_cbc();
559         break;
560     case NID_aes_192_cfb:
561         *cipher = padlock_aes_192_cfb();
562         break;
563     case NID_aes_192_ofb:
564         *cipher = padlock_aes_192_ofb();
565         break;
566     case NID_aes_192_ctr:
567         *cipher = padlock_aes_192_ctr();
568         break;
569 
570     case NID_aes_256_ecb:
571         *cipher = padlock_aes_256_ecb();
572         break;
573     case NID_aes_256_cbc:
574         *cipher = padlock_aes_256_cbc();
575         break;
576     case NID_aes_256_cfb:
577         *cipher = padlock_aes_256_cfb();
578         break;
579     case NID_aes_256_ofb:
580         *cipher = padlock_aes_256_ofb();
581         break;
582     case NID_aes_256_ctr:
583         *cipher = padlock_aes_256_ctr();
584         break;
585 
586     default:
587         /* Sorry, we don't support this NID */
588         *cipher = NULL;
589         return 0;
590     }
591 
592     return 1;
593 }
594 
595 /* Prepare the encryption key for PadLock usage */
596 static int
597 padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
598                      const unsigned char *iv, int enc)
599 {
600     struct padlock_cipher_data *cdata;
601     int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
602     unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
603 
604     if (key == NULL)
605         return 0;               /* ERROR */
606 
607     cdata = ALIGNED_CIPHER_DATA(ctx);
608     memset(cdata, 0, sizeof(*cdata));
609 
610     /* Prepare Control word. */
611     if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
612         cdata->cword.b.encdec = 0;
613     else
614         cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
615     cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
616     cdata->cword.b.ksize = (key_len - 128) / 64;
617 
618     switch (key_len) {
619     case 128:
620         /*
621          * PadLock can generate an extended key for AES128 in hardware
622          */
623         memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
624         cdata->cword.b.keygen = 0;
625         break;
626 
627     case 192:
628     case 256:
629         /*
630          * Generate an extended AES key in software. Needed for AES192/AES256
631          */
632         /*
633          * Well, the above applies to Stepping 8 CPUs and is listed as
634          * hardware errata. They most likely will fix it at some point and
635          * then a check for stepping would be due here.
636          */
637         if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
638             && !enc)
639             AES_set_decrypt_key(key, key_len, &cdata->ks);
640         else
641             AES_set_encrypt_key(key, key_len, &cdata->ks);
642 #   ifndef AES_ASM
643         /*
644          * OpenSSL C functions use byte-swapped extended key.
645          */
646         padlock_key_bswap(&cdata->ks);
647 #   endif
648         cdata->cword.b.keygen = 1;
649         break;
650 
651     default:
652         /* ERROR */
653         return 0;
654     }
655 
656     /*
657      * This is done to cover for cases when user reuses the
658      * context for new key. The catch is that if we don't do
659      * this, padlock_eas_cipher might proceed with old key...
660      */
661     padlock_reload_key();
662 
663     return 1;
664 }
665 
666 /* ===== Random Number Generator ===== */
667 /*
668  * This code is not engaged. The reason is that it does not comply
669  * with recommendations for VIA RNG usage for secure applications
670  * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
671  * provide meaningful error control...
672  */
673 /*
674  * Wrapper that provides an interface between the API and the raw PadLock
675  * RNG
676  */
677 static int padlock_rand_bytes(unsigned char *output, int count)
678 {
679     unsigned int eax, buf;
680 
681     while (count >= 8) {
682         eax = padlock_xstore(output, 0);
683         if (!(eax & (1 << 6)))
684             return 0;           /* RNG disabled */
685         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
686         if (eax & (0x1F << 10))
687             return 0;
688         if ((eax & 0x1F) == 0)
689             continue;           /* no data, retry... */
690         if ((eax & 0x1F) != 8)
691             return 0;           /* fatal failure...  */
692         output += 8;
693         count -= 8;
694     }
695     while (count > 0) {
696         eax = padlock_xstore(&buf, 3);
697         if (!(eax & (1 << 6)))
698             return 0;           /* RNG disabled */
699         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
700         if (eax & (0x1F << 10))
701             return 0;
702         if ((eax & 0x1F) == 0)
703             continue;           /* no data, retry... */
704         if ((eax & 0x1F) != 1)
705             return 0;           /* fatal failure...  */
706         *output++ = (unsigned char)buf;
707         count--;
708     }
709     OPENSSL_cleanse(&buf, sizeof(buf));
710 
711     return 1;
712 }
713 
714 /* Dummy but necessary function */
715 static int padlock_rand_status(void)
716 {
717     return 1;
718 }
719 
720 /* Prepare structure for registration */
721 static RAND_METHOD padlock_rand = {
722     NULL,                       /* seed */
723     padlock_rand_bytes,         /* bytes */
724     NULL,                       /* cleanup */
725     NULL,                       /* add */
726     padlock_rand_bytes,         /* pseudorand */
727     padlock_rand_status,        /* rand status */
728 };
729 
730 #  endif                        /* COMPILE_HW_PADLOCK */
731 # endif                         /* !OPENSSL_NO_HW_PADLOCK */
732 #endif                          /* !OPENSSL_NO_HW */
733 
734 #if defined(OPENSSL_NO_HW) || defined(OPENSSL_NO_HW_PADLOCK) \
735         || !defined(COMPILE_HW_PADLOCK)
736 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
737 OPENSSL_EXPORT
738     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
739 OPENSSL_EXPORT
740     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
741 {
742     return 0;
743 }
744 
745 IMPLEMENT_DYNAMIC_CHECK_FN()
746 # endif
747 #endif
748