1 /*
2  * Copyright 2020-2021 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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 <openssl/crypto.h>
11 #include <openssl/core_dispatch.h>
12 #include <openssl/core_names.h>
13 #include <openssl/err.h>
14 #include <openssl/params.h>
15 #include <openssl/evp.h>
16 #include <openssl/err.h>
17 #include <openssl/proverr.h>
18 #include "internal/nelem.h"
19 #include "internal/sizes.h"
20 #include "prov/providercommon.h"
21 #include "prov/implementations.h"
22 #include "prov/provider_ctx.h"
23 #include "prov/der_ecx.h"
24 #include "crypto/ecx.h"
25 
26 #ifdef S390X_EC_ASM
27 # include "s390x_arch.h"
28 
29 # define S390X_CAN_SIGN(edtype)                                                \
30 ((OPENSSL_s390xcap_P.pcc[1] & S390X_CAPBIT(S390X_SCALAR_MULTIPLY_##edtype))    \
31 && (OPENSSL_s390xcap_P.kdsa[0] & S390X_CAPBIT(S390X_EDDSA_SIGN_##edtype))      \
32 && (OPENSSL_s390xcap_P.kdsa[0] & S390X_CAPBIT(S390X_EDDSA_VERIFY_##edtype)))
33 
34 static int s390x_ed25519_digestsign(const ECX_KEY *edkey, unsigned char *sig,
35                                     const unsigned char *tbs, size_t tbslen);
36 static int s390x_ed448_digestsign(const ECX_KEY *edkey, unsigned char *sig,
37                                   const unsigned char *tbs, size_t tbslen);
38 static int s390x_ed25519_digestverify(const ECX_KEY *edkey,
39                                       const unsigned char *sig,
40                                       const unsigned char *tbs, size_t tbslen);
41 static int s390x_ed448_digestverify(const ECX_KEY *edkey,
42                                     const unsigned char *sig,
43                                     const unsigned char *tbs, size_t tbslen);
44 
45 #endif /* S390X_EC_ASM */
46 
47 static OSSL_FUNC_signature_newctx_fn eddsa_newctx;
48 static OSSL_FUNC_signature_digest_sign_init_fn eddsa_digest_signverify_init;
49 static OSSL_FUNC_signature_digest_sign_fn ed25519_digest_sign;
50 static OSSL_FUNC_signature_digest_sign_fn ed448_digest_sign;
51 static OSSL_FUNC_signature_digest_verify_fn ed25519_digest_verify;
52 static OSSL_FUNC_signature_digest_verify_fn ed448_digest_verify;
53 static OSSL_FUNC_signature_freectx_fn eddsa_freectx;
54 static OSSL_FUNC_signature_dupctx_fn eddsa_dupctx;
55 static OSSL_FUNC_signature_get_ctx_params_fn eddsa_get_ctx_params;
56 static OSSL_FUNC_signature_gettable_ctx_params_fn eddsa_gettable_ctx_params;
57 
58 typedef struct {
59     OSSL_LIB_CTX *libctx;
60     ECX_KEY *key;
61 
62     /* The Algorithm Identifier of the signature algorithm */
63     unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
64     unsigned char *aid;
65     size_t  aid_len;
66 } PROV_EDDSA_CTX;
67 
eddsa_newctx(void * provctx,const char * propq_unused)68 static void *eddsa_newctx(void *provctx, const char *propq_unused)
69 {
70     PROV_EDDSA_CTX *peddsactx;
71 
72     if (!ossl_prov_is_running())
73         return NULL;
74 
75     peddsactx = OPENSSL_zalloc(sizeof(PROV_EDDSA_CTX));
76     if (peddsactx == NULL) {
77         ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
78         return NULL;
79     }
80 
81     peddsactx->libctx = PROV_LIBCTX_OF(provctx);
82 
83     return peddsactx;
84 }
85 
eddsa_digest_signverify_init(void * vpeddsactx,const char * mdname,void * vedkey,ossl_unused const OSSL_PARAM params[])86 static int eddsa_digest_signverify_init(void *vpeddsactx, const char *mdname,
87                                         void *vedkey,
88                                         ossl_unused const OSSL_PARAM params[])
89 {
90     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
91     ECX_KEY *edkey = (ECX_KEY *)vedkey;
92     WPACKET pkt;
93     int ret;
94 
95     if (!ossl_prov_is_running())
96         return 0;
97 
98     if (mdname != NULL && mdname[0] != '\0') {
99         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST);
100         return 0;
101     }
102 
103     if (edkey == NULL) {
104         if (peddsactx->key != NULL)
105             /* there is nothing to do on reinit */
106             return 1;
107         ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
108         return 0;
109     }
110 
111     if (!ossl_ecx_key_up_ref(edkey)) {
112         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
113         return 0;
114     }
115 
116     /*
117      * We do not care about DER writing errors.
118      * All it really means is that for some reason, there's no
119      * AlgorithmIdentifier to be had, but the operation itself is
120      * still valid, just as long as it's not used to construct
121      * anything that needs an AlgorithmIdentifier.
122      */
123     peddsactx->aid_len = 0;
124     ret = WPACKET_init_der(&pkt, peddsactx->aid_buf, sizeof(peddsactx->aid_buf));
125     switch (edkey->type) {
126     case ECX_KEY_TYPE_ED25519:
127         ret = ret && ossl_DER_w_algorithmIdentifier_ED25519(&pkt, -1, edkey);
128         break;
129     case ECX_KEY_TYPE_ED448:
130         ret = ret && ossl_DER_w_algorithmIdentifier_ED448(&pkt, -1, edkey);
131         break;
132     default:
133         /* Should never happen */
134         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
135         ossl_ecx_key_free(edkey);
136         return 0;
137     }
138     if (ret && WPACKET_finish(&pkt)) {
139         WPACKET_get_total_written(&pkt, &peddsactx->aid_len);
140         peddsactx->aid = WPACKET_get_curr(&pkt);
141     }
142     WPACKET_cleanup(&pkt);
143 
144     peddsactx->key = edkey;
145 
146     return 1;
147 }
148 
ed25519_digest_sign(void * vpeddsactx,unsigned char * sigret,size_t * siglen,size_t sigsize,const unsigned char * tbs,size_t tbslen)149 int ed25519_digest_sign(void *vpeddsactx, unsigned char *sigret,
150                         size_t *siglen, size_t sigsize,
151                         const unsigned char *tbs, size_t tbslen)
152 {
153     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
154     const ECX_KEY *edkey = peddsactx->key;
155 
156     if (!ossl_prov_is_running())
157         return 0;
158 
159     if (sigret == NULL) {
160         *siglen = ED25519_SIGSIZE;
161         return 1;
162     }
163     if (sigsize < ED25519_SIGSIZE) {
164         ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
165         return 0;
166     }
167 #ifdef S390X_EC_ASM
168     if (S390X_CAN_SIGN(ED25519))
169         return s390x_ed25519_digestsign(edkey, sigret, tbs, tbslen);
170 #endif /* S390X_EC_ASM */
171     if (ossl_ed25519_sign(sigret, tbs, tbslen, edkey->pubkey, edkey->privkey,
172                           peddsactx->libctx, NULL) == 0) {
173         ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SIGN);
174         return 0;
175     }
176     *siglen = ED25519_SIGSIZE;
177     return 1;
178 }
179 
ed448_digest_sign(void * vpeddsactx,unsigned char * sigret,size_t * siglen,size_t sigsize,const unsigned char * tbs,size_t tbslen)180 int ed448_digest_sign(void *vpeddsactx, unsigned char *sigret,
181                       size_t *siglen, size_t sigsize,
182                       const unsigned char *tbs, size_t tbslen)
183 {
184     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
185     const ECX_KEY *edkey = peddsactx->key;
186 
187     if (!ossl_prov_is_running())
188         return 0;
189 
190     if (sigret == NULL) {
191         *siglen = ED448_SIGSIZE;
192         return 1;
193     }
194     if (sigsize < ED448_SIGSIZE) {
195         ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
196         return 0;
197     }
198 #ifdef S390X_EC_ASM
199     if (S390X_CAN_SIGN(ED448))
200         return s390x_ed448_digestsign(edkey, sigret, tbs, tbslen);
201 #endif /* S390X_EC_ASM */
202     if (ossl_ed448_sign(peddsactx->libctx, sigret, tbs, tbslen, edkey->pubkey,
203                         edkey->privkey, NULL, 0, edkey->propq) == 0) {
204         ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SIGN);
205         return 0;
206     }
207     *siglen = ED448_SIGSIZE;
208     return 1;
209 }
210 
ed25519_digest_verify(void * vpeddsactx,const unsigned char * sig,size_t siglen,const unsigned char * tbs,size_t tbslen)211 int ed25519_digest_verify(void *vpeddsactx, const unsigned char *sig,
212                           size_t siglen, const unsigned char *tbs,
213                           size_t tbslen)
214 {
215     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
216     const ECX_KEY *edkey = peddsactx->key;
217 
218     if (!ossl_prov_is_running() || siglen != ED25519_SIGSIZE)
219         return 0;
220 
221 #ifdef S390X_EC_ASM
222     if (S390X_CAN_SIGN(ED25519))
223         return s390x_ed25519_digestverify(edkey, sig, tbs, tbslen);
224 #endif /* S390X_EC_ASM */
225 
226     return ossl_ed25519_verify(tbs, tbslen, sig, edkey->pubkey,
227                                peddsactx->libctx, edkey->propq);
228 }
229 
ed448_digest_verify(void * vpeddsactx,const unsigned char * sig,size_t siglen,const unsigned char * tbs,size_t tbslen)230 int ed448_digest_verify(void *vpeddsactx, const unsigned char *sig,
231                         size_t siglen, const unsigned char *tbs,
232                         size_t tbslen)
233 {
234     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
235     const ECX_KEY *edkey = peddsactx->key;
236 
237     if (!ossl_prov_is_running() || siglen != ED448_SIGSIZE)
238         return 0;
239 
240 #ifdef S390X_EC_ASM
241     if (S390X_CAN_SIGN(ED448))
242         return s390x_ed448_digestverify(edkey, sig, tbs, tbslen);
243 #endif /* S390X_EC_ASM */
244 
245     return ossl_ed448_verify(peddsactx->libctx, tbs, tbslen, sig, edkey->pubkey,
246                              NULL, 0, edkey->propq);
247 }
248 
eddsa_freectx(void * vpeddsactx)249 static void eddsa_freectx(void *vpeddsactx)
250 {
251     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
252 
253     ossl_ecx_key_free(peddsactx->key);
254 
255     OPENSSL_free(peddsactx);
256 }
257 
eddsa_dupctx(void * vpeddsactx)258 static void *eddsa_dupctx(void *vpeddsactx)
259 {
260     PROV_EDDSA_CTX *srcctx = (PROV_EDDSA_CTX *)vpeddsactx;
261     PROV_EDDSA_CTX *dstctx;
262 
263     if (!ossl_prov_is_running())
264         return NULL;
265 
266     dstctx = OPENSSL_zalloc(sizeof(*srcctx));
267     if (dstctx == NULL)
268         return NULL;
269 
270     *dstctx = *srcctx;
271     dstctx->key = NULL;
272 
273     if (srcctx->key != NULL && !ossl_ecx_key_up_ref(srcctx->key)) {
274         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
275         goto err;
276     }
277     dstctx->key = srcctx->key;
278 
279     return dstctx;
280  err:
281     eddsa_freectx(dstctx);
282     return NULL;
283 }
284 
eddsa_get_ctx_params(void * vpeddsactx,OSSL_PARAM * params)285 static int eddsa_get_ctx_params(void *vpeddsactx, OSSL_PARAM *params)
286 {
287     PROV_EDDSA_CTX *peddsactx = (PROV_EDDSA_CTX *)vpeddsactx;
288     OSSL_PARAM *p;
289 
290     if (peddsactx == NULL)
291         return 0;
292 
293     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
294     if (p != NULL && !OSSL_PARAM_set_octet_string(p, peddsactx->aid,
295                                                   peddsactx->aid_len))
296         return 0;
297 
298     return 1;
299 }
300 
301 static const OSSL_PARAM known_gettable_ctx_params[] = {
302     OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
303     OSSL_PARAM_END
304 };
305 
eddsa_gettable_ctx_params(ossl_unused void * vpeddsactx,ossl_unused void * provctx)306 static const OSSL_PARAM *eddsa_gettable_ctx_params(ossl_unused void *vpeddsactx,
307                                                    ossl_unused void *provctx)
308 {
309     return known_gettable_ctx_params;
310 }
311 
312 const OSSL_DISPATCH ossl_ed25519_signature_functions[] = {
313     { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))eddsa_newctx },
314     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
315       (void (*)(void))eddsa_digest_signverify_init },
316     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN,
317       (void (*)(void))ed25519_digest_sign },
318     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
319       (void (*)(void))eddsa_digest_signverify_init },
320     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY,
321       (void (*)(void))ed25519_digest_verify },
322     { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))eddsa_freectx },
323     { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))eddsa_dupctx },
324     { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))eddsa_get_ctx_params },
325     { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
326       (void (*)(void))eddsa_gettable_ctx_params },
327     { 0, NULL }
328 };
329 
330 const OSSL_DISPATCH ossl_ed448_signature_functions[] = {
331     { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))eddsa_newctx },
332     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
333       (void (*)(void))eddsa_digest_signverify_init },
334     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN,
335       (void (*)(void))ed448_digest_sign },
336     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
337       (void (*)(void))eddsa_digest_signverify_init },
338     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY,
339       (void (*)(void))ed448_digest_verify },
340     { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))eddsa_freectx },
341     { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))eddsa_dupctx },
342     { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))eddsa_get_ctx_params },
343     { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
344       (void (*)(void))eddsa_gettable_ctx_params },
345     { 0, NULL }
346 };
347 
348 #ifdef S390X_EC_ASM
349 
s390x_ed25519_digestsign(const ECX_KEY * edkey,unsigned char * sig,const unsigned char * tbs,size_t tbslen)350 static int s390x_ed25519_digestsign(const ECX_KEY *edkey, unsigned char *sig,
351                                     const unsigned char *tbs, size_t tbslen)
352 {
353     int rc;
354     union {
355         struct {
356             unsigned char sig[64];
357             unsigned char priv[32];
358         } ed25519;
359         unsigned long long buff[512];
360     } param;
361 
362     memset(&param, 0, sizeof(param));
363     memcpy(param.ed25519.priv, edkey->privkey, sizeof(param.ed25519.priv));
364 
365     rc = s390x_kdsa(S390X_EDDSA_SIGN_ED25519, &param.ed25519, tbs, tbslen);
366     OPENSSL_cleanse(param.ed25519.priv, sizeof(param.ed25519.priv));
367     if (rc != 0)
368         return 0;
369 
370     s390x_flip_endian32(sig, param.ed25519.sig);
371     s390x_flip_endian32(sig + 32, param.ed25519.sig + 32);
372     return 1;
373 }
374 
s390x_ed448_digestsign(const ECX_KEY * edkey,unsigned char * sig,const unsigned char * tbs,size_t tbslen)375 static int s390x_ed448_digestsign(const ECX_KEY *edkey, unsigned char *sig,
376                                   const unsigned char *tbs, size_t tbslen)
377 {
378     int rc;
379     union {
380         struct {
381             unsigned char sig[128];
382             unsigned char priv[64];
383         } ed448;
384         unsigned long long buff[512];
385     } param;
386 
387     memset(&param, 0, sizeof(param));
388     memcpy(param.ed448.priv + 64 - 57, edkey->privkey, 57);
389 
390     rc = s390x_kdsa(S390X_EDDSA_SIGN_ED448, &param.ed448, tbs, tbslen);
391     OPENSSL_cleanse(param.ed448.priv, sizeof(param.ed448.priv));
392     if (rc != 0)
393         return 0;
394 
395     s390x_flip_endian64(param.ed448.sig, param.ed448.sig);
396     s390x_flip_endian64(param.ed448.sig + 64, param.ed448.sig + 64);
397     memcpy(sig, param.ed448.sig, 57);
398     memcpy(sig + 57, param.ed448.sig + 64, 57);
399     return 1;
400 }
401 
s390x_ed25519_digestverify(const ECX_KEY * edkey,const unsigned char * sig,const unsigned char * tbs,size_t tbslen)402 static int s390x_ed25519_digestverify(const ECX_KEY *edkey,
403                                       const unsigned char *sig,
404                                       const unsigned char *tbs, size_t tbslen)
405 {
406     union {
407         struct {
408             unsigned char sig[64];
409             unsigned char pub[32];
410         } ed25519;
411         unsigned long long buff[512];
412     } param;
413 
414     memset(&param, 0, sizeof(param));
415     s390x_flip_endian32(param.ed25519.sig, sig);
416     s390x_flip_endian32(param.ed25519.sig + 32, sig + 32);
417     s390x_flip_endian32(param.ed25519.pub, edkey->pubkey);
418 
419     return s390x_kdsa(S390X_EDDSA_VERIFY_ED25519,
420                       &param.ed25519, tbs, tbslen) == 0 ? 1 : 0;
421 }
422 
s390x_ed448_digestverify(const ECX_KEY * edkey,const unsigned char * sig,const unsigned char * tbs,size_t tbslen)423 static int s390x_ed448_digestverify(const ECX_KEY *edkey,
424                                     const unsigned char *sig,
425                                     const unsigned char *tbs,
426                                     size_t tbslen)
427 {
428     union {
429         struct {
430             unsigned char sig[128];
431             unsigned char pub[64];
432         } ed448;
433         unsigned long long buff[512];
434     } param;
435 
436     memset(&param, 0, sizeof(param));
437     memcpy(param.ed448.sig, sig, 57);
438     s390x_flip_endian64(param.ed448.sig, param.ed448.sig);
439     memcpy(param.ed448.sig + 64, sig + 57, 57);
440     s390x_flip_endian64(param.ed448.sig + 64, param.ed448.sig + 64);
441     memcpy(param.ed448.pub, edkey->pubkey, 57);
442     s390x_flip_endian64(param.ed448.pub, param.ed448.pub);
443 
444     return s390x_kdsa(S390X_EDDSA_VERIFY_ED448,
445                       &param.ed448, tbs, tbslen) == 0 ? 1 : 0;
446 }
447 
448 #endif /* S390X_EC_ASM */
449