2 * Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
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
11 * RSA low level APIs are deprecated for public use, but still ok for
14 #include "internal/deprecated.h"
16 #include "e_os.h" /* strcasecmp */
17 #include <openssl/crypto.h>
18 #include <openssl/evp.h>
19 #include <openssl/core_dispatch.h>
20 #include <openssl/core_names.h>
21 #include <openssl/rsa.h>
22 #include <openssl/params.h>
23 #include <openssl/err.h>
24 #include <crypto/rsa.h>
25 #include "prov/providercommonerr.h"
26 #include "prov/provider_ctx.h"
27 #include "prov/implementations.h"
29 static OSSL_FUNC_kem_newctx_fn rsakem_newctx;
30 static OSSL_FUNC_kem_encapsulate_init_fn rsakem_init;
31 static OSSL_FUNC_kem_encapsulate_fn rsakem_generate;
32 static OSSL_FUNC_kem_decapsulate_init_fn rsakem_init;
33 static OSSL_FUNC_kem_decapsulate_fn rsakem_recover;
34 static OSSL_FUNC_kem_freectx_fn rsakem_freectx;
35 static OSSL_FUNC_kem_dupctx_fn rsakem_dupctx;
36 static OSSL_FUNC_kem_get_ctx_params_fn rsakem_get_ctx_params;
37 static OSSL_FUNC_kem_gettable_ctx_params_fn rsakem_gettable_ctx_params;
38 static OSSL_FUNC_kem_set_ctx_params_fn rsakem_set_ctx_params;
39 static OSSL_FUNC_kem_settable_ctx_params_fn rsakem_settable_ctx_params;
42 * Only the KEM for RSASVE as defined in SP800-56b r2 is implemented
45 #define KEM_OP_UNDEFINED -1
46 #define KEM_OP_RSASVE 0
49 * What's passed as an actual key is defined by the KEYMGMT interface.
50 * We happen to know that our KEYMGMT simply passes RSA structures, so
51 * we use that here too.
59 static const OSSL_ITEM rsakem_opname_id_map[] = {
60 { KEM_OP_RSASVE, OSSL_KEM_PARAM_OPERATION_RSASVE },
63 static int name2id(const char *name, const OSSL_ITEM *map, size_t sz)
70 for (i = 0; i < sz; ++i) {
71 if (strcasecmp(map[i].ptr, name) == 0)
77 static int rsakem_opname2id(const char *name)
79 return name2id(name, rsakem_opname_id_map, OSSL_NELEM(rsakem_opname_id_map));
82 static void *rsakem_newctx(void *provctx)
84 PROV_RSA_CTX *prsactx = OPENSSL_zalloc(sizeof(PROV_RSA_CTX));
88 prsactx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
89 prsactx->op = KEM_OP_UNDEFINED;
94 static void rsakem_freectx(void *vprsactx)
96 PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
98 RSA_free(prsactx->rsa);
99 OPENSSL_free(prsactx);
102 static void *rsakem_dupctx(void *vprsactx)
104 PROV_RSA_CTX *srcctx = (PROV_RSA_CTX *)vprsactx;
105 PROV_RSA_CTX *dstctx;
107 dstctx = OPENSSL_zalloc(sizeof(*srcctx));
112 if (dstctx->rsa != NULL && !RSA_up_ref(dstctx->rsa)) {
113 OPENSSL_free(dstctx);
119 static int rsakem_init(void *vprsactx, void *vrsa)
121 PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
123 if (prsactx == NULL || vrsa == NULL || !RSA_up_ref(vrsa))
125 RSA_free(prsactx->rsa);
127 /* TODO(3.0) Add a RSA keylength check here for fips */
131 static int rsakem_get_ctx_params(void *vprsactx, OSSL_PARAM *params)
133 PROV_RSA_CTX *ctx = (PROV_RSA_CTX *)vprsactx;
135 if (ctx == NULL || params == NULL)
140 static const OSSL_PARAM known_gettable_rsakem_ctx_params[] = {
144 static const OSSL_PARAM *rsakem_gettable_ctx_params(ossl_unused void *provctx)
146 return known_gettable_rsakem_ctx_params;
149 static int rsakem_set_ctx_params(void *vprsactx, const OSSL_PARAM params[])
151 PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
155 if (prsactx == NULL || params == NULL)
158 p = OSSL_PARAM_locate_const(params, OSSL_KEM_PARAM_OPERATION);
160 if (p->data_type != OSSL_PARAM_UTF8_STRING)
162 op = rsakem_opname2id(p->data);
170 static const OSSL_PARAM known_settable_rsakem_ctx_params[] = {
171 OSSL_PARAM_utf8_string(OSSL_KEM_PARAM_OPERATION, NULL, 0),
175 static const OSSL_PARAM *rsakem_settable_ctx_params(ossl_unused void *provctx)
177 return known_settable_rsakem_ctx_params;
182 * 7.2.1.2 RSASVE Generate Operation (RSASVE.GENERATE).
184 * Generate a random in the range 1 < z < (n – 1)
186 static int rsasve_gen_rand_bytes(RSA *rsa_pub,
187 unsigned char *out, int outlen)
193 bnctx = BN_CTX_secure_new_ex(rsa_get0_libctx(rsa_pub));
198 * Generate a random in the range 1 < z < (n – 1).
199 * Since BN_priv_rand_range_ex() returns a value in range 0 <= r < max
200 * We can achieve this by adding 2.. but then we need to subtract 3 from
201 * the upper bound i.e: 2 + (0 <= r < (n - 3))
204 nminus3 = BN_CTX_get(bnctx);
205 z = BN_CTX_get(bnctx);
207 && (BN_copy(nminus3, RSA_get0_n(rsa_pub)) != NULL)
208 && BN_sub_word(nminus3, 3)
209 && BN_priv_rand_range_ex(z, nminus3, bnctx)
211 && (BN_bn2binpad(z, out, outlen) == outlen));
219 * 7.2.1.2 RSASVE Generate Operation (RSASVE.GENERATE).
221 static int rsasve_generate(PROV_RSA_CTX *prsactx,
222 unsigned char *out, size_t *outlen,
223 unsigned char *secret, size_t *secretlen)
228 /* Step (1): nlen = Ceil(len(n)/8) */
229 nlen = RSA_size(prsactx->rsa);
233 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY);
236 if (outlen == NULL && secretlen == NULL)
240 if (secretlen != NULL)
245 * Step (2): Generate a random byte string z of nlen bytes where
248 if (!rsasve_gen_rand_bytes(prsactx->rsa, secret, nlen))
251 /* Step(3): out = RSAEP((n,e), z) */
252 ret = RSA_public_encrypt(nlen, secret, out, prsactx->rsa, RSA_NO_PADDING);
257 if (secretlen != NULL)
260 OPENSSL_cleanse(secret, nlen);
267 * 7.2.1.3 RSASVE Recovery Operation (RSASVE.RECOVER).
269 static int rsasve_recover(PROV_RSA_CTX *prsactx,
270 unsigned char *out, size_t *outlen,
271 const unsigned char *in, size_t inlen)
275 /* Step (1): get the byte length of n */
276 nlen = RSA_size(prsactx->rsa);
280 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY);
287 /* Step (2): check the input ciphertext 'inlen' matches the nlen */
289 ERR_raise(ERR_LIB_PROV, PROV_R_BAD_LENGTH);
292 /* Step (3): out = RSADP((n,d), in) */
293 return (RSA_private_decrypt(inlen, in, out, prsactx->rsa, RSA_NO_PADDING) > 0);
296 static int rsakem_generate(void *vprsactx, unsigned char *out, size_t *outlen,
297 unsigned char *secret, size_t *secretlen)
299 PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
301 switch (prsactx->op) {
303 return rsasve_generate(prsactx, out, outlen, secret, secretlen);
309 static int rsakem_recover(void *vprsactx, unsigned char *out, size_t *outlen,
310 const unsigned char *in, size_t inlen)
312 PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
314 switch (prsactx->op) {
316 return rsasve_recover(prsactx, out, outlen, in, inlen);
322 const OSSL_DISPATCH rsa_asym_kem_functions[] = {
323 { OSSL_FUNC_KEM_NEWCTX, (void (*)(void))rsakem_newctx },
324 { OSSL_FUNC_KEM_ENCAPSULATE_INIT,
325 (void (*)(void))rsakem_init },
326 { OSSL_FUNC_KEM_ENCAPSULATE, (void (*)(void))rsakem_generate },
327 { OSSL_FUNC_KEM_DECAPSULATE_INIT,
328 (void (*)(void))rsakem_init },
329 { OSSL_FUNC_KEM_DECAPSULATE, (void (*)(void))rsakem_recover },
330 { OSSL_FUNC_KEM_FREECTX, (void (*)(void))rsakem_freectx },
331 { OSSL_FUNC_KEM_DUPCTX, (void (*)(void))rsakem_dupctx },
332 { OSSL_FUNC_KEM_GET_CTX_PARAMS,
333 (void (*)(void))rsakem_get_ctx_params },
334 { OSSL_FUNC_KEM_GETTABLE_CTX_PARAMS,
335 (void (*)(void))rsakem_gettable_ctx_params },
336 { OSSL_FUNC_KEM_SET_CTX_PARAMS,
337 (void (*)(void))rsakem_set_ctx_params },
338 { OSSL_FUNC_KEM_SETTABLE_CTX_PARAMS,
339 (void (*)(void))rsakem_settable_ctx_params },