1 | /* |
2 | * Copyright 2006-2018 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 "internal/cryptlib.h" |
11 | #include <openssl/asn1t.h> |
12 | #include <openssl/ec.h> |
13 | #include <openssl/evp.h> |
14 | #include "crypto/evp.h" |
15 | #include "crypto/sm2.h" |
16 | #include "crypto/sm2err.h" |
17 | |
18 | /* EC pkey context structure */ |
19 | |
20 | typedef struct { |
21 | /* Key and paramgen group */ |
22 | EC_GROUP *gen_group; |
23 | /* message digest */ |
24 | const EVP_MD *md; |
25 | /* Distinguishing Identifier, ISO/IEC 15946-3 */ |
26 | uint8_t *id; |
27 | size_t id_len; |
28 | /* id_set indicates if the 'id' field is set (1) or not (0) */ |
29 | int id_set; |
30 | } SM2_PKEY_CTX; |
31 | |
32 | static int pkey_sm2_init(EVP_PKEY_CTX *ctx) |
33 | { |
34 | SM2_PKEY_CTX *smctx; |
35 | |
36 | if ((smctx = OPENSSL_zalloc(sizeof(*smctx))) == NULL) { |
37 | SM2err(SM2_F_PKEY_SM2_INIT, ERR_R_MALLOC_FAILURE); |
38 | return 0; |
39 | } |
40 | |
41 | ctx->data = smctx; |
42 | return 1; |
43 | } |
44 | |
45 | static void pkey_sm2_cleanup(EVP_PKEY_CTX *ctx) |
46 | { |
47 | SM2_PKEY_CTX *smctx = ctx->data; |
48 | |
49 | if (smctx != NULL) { |
50 | EC_GROUP_free(smctx->gen_group); |
51 | OPENSSL_free(smctx->id); |
52 | OPENSSL_free(smctx); |
53 | ctx->data = NULL; |
54 | } |
55 | } |
56 | |
57 | static int pkey_sm2_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src) |
58 | { |
59 | SM2_PKEY_CTX *dctx, *sctx; |
60 | |
61 | if (!pkey_sm2_init(dst)) |
62 | return 0; |
63 | sctx = src->data; |
64 | dctx = dst->data; |
65 | if (sctx->gen_group != NULL) { |
66 | dctx->gen_group = EC_GROUP_dup(sctx->gen_group); |
67 | if (dctx->gen_group == NULL) { |
68 | pkey_sm2_cleanup(dst); |
69 | return 0; |
70 | } |
71 | } |
72 | if (sctx->id != NULL) { |
73 | dctx->id = OPENSSL_malloc(sctx->id_len); |
74 | if (dctx->id == NULL) { |
75 | SM2err(SM2_F_PKEY_SM2_COPY, ERR_R_MALLOC_FAILURE); |
76 | pkey_sm2_cleanup(dst); |
77 | return 0; |
78 | } |
79 | memcpy(dctx->id, sctx->id, sctx->id_len); |
80 | } |
81 | dctx->id_len = sctx->id_len; |
82 | dctx->id_set = sctx->id_set; |
83 | dctx->md = sctx->md; |
84 | |
85 | return 1; |
86 | } |
87 | |
88 | static int pkey_sm2_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen, |
89 | const unsigned char *tbs, size_t tbslen) |
90 | { |
91 | int ret; |
92 | unsigned int sltmp; |
93 | EC_KEY *ec = ctx->pkey->pkey.ec; |
94 | const int sig_sz = ECDSA_size(ctx->pkey->pkey.ec); |
95 | |
96 | if (sig_sz <= 0) { |
97 | return 0; |
98 | } |
99 | |
100 | if (sig == NULL) { |
101 | *siglen = (size_t)sig_sz; |
102 | return 1; |
103 | } |
104 | |
105 | if (*siglen < (size_t)sig_sz) { |
106 | SM2err(SM2_F_PKEY_SM2_SIGN, SM2_R_BUFFER_TOO_SMALL); |
107 | return 0; |
108 | } |
109 | |
110 | ret = sm2_sign(tbs, tbslen, sig, &sltmp, ec); |
111 | |
112 | if (ret <= 0) |
113 | return ret; |
114 | *siglen = (size_t)sltmp; |
115 | return 1; |
116 | } |
117 | |
118 | static int pkey_sm2_verify(EVP_PKEY_CTX *ctx, |
119 | const unsigned char *sig, size_t siglen, |
120 | const unsigned char *tbs, size_t tbslen) |
121 | { |
122 | EC_KEY *ec = ctx->pkey->pkey.ec; |
123 | |
124 | return sm2_verify(tbs, tbslen, sig, siglen, ec); |
125 | } |
126 | |
127 | static int pkey_sm2_encrypt(EVP_PKEY_CTX *ctx, |
128 | unsigned char *out, size_t *outlen, |
129 | const unsigned char *in, size_t inlen) |
130 | { |
131 | EC_KEY *ec = ctx->pkey->pkey.ec; |
132 | SM2_PKEY_CTX *dctx = ctx->data; |
133 | const EVP_MD *md = (dctx->md == NULL) ? EVP_sm3() : dctx->md; |
134 | |
135 | if (out == NULL) { |
136 | if (!sm2_ciphertext_size(ec, md, inlen, outlen)) |
137 | return -1; |
138 | else |
139 | return 1; |
140 | } |
141 | |
142 | return sm2_encrypt(ec, md, in, inlen, out, outlen); |
143 | } |
144 | |
145 | static int pkey_sm2_decrypt(EVP_PKEY_CTX *ctx, |
146 | unsigned char *out, size_t *outlen, |
147 | const unsigned char *in, size_t inlen) |
148 | { |
149 | EC_KEY *ec = ctx->pkey->pkey.ec; |
150 | SM2_PKEY_CTX *dctx = ctx->data; |
151 | const EVP_MD *md = (dctx->md == NULL) ? EVP_sm3() : dctx->md; |
152 | |
153 | if (out == NULL) { |
154 | if (!sm2_plaintext_size(ec, md, inlen, outlen)) |
155 | return -1; |
156 | else |
157 | return 1; |
158 | } |
159 | |
160 | return sm2_decrypt(ec, md, in, inlen, out, outlen); |
161 | } |
162 | |
163 | static int pkey_sm2_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) |
164 | { |
165 | SM2_PKEY_CTX *smctx = ctx->data; |
166 | EC_GROUP *group; |
167 | uint8_t *tmp_id; |
168 | |
169 | switch (type) { |
170 | case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID: |
171 | group = EC_GROUP_new_by_curve_name(p1); |
172 | if (group == NULL) { |
173 | SM2err(SM2_F_PKEY_SM2_CTRL, SM2_R_INVALID_CURVE); |
174 | return 0; |
175 | } |
176 | EC_GROUP_free(smctx->gen_group); |
177 | smctx->gen_group = group; |
178 | return 1; |
179 | |
180 | case EVP_PKEY_CTRL_EC_PARAM_ENC: |
181 | if (smctx->gen_group == NULL) { |
182 | SM2err(SM2_F_PKEY_SM2_CTRL, SM2_R_NO_PARAMETERS_SET); |
183 | return 0; |
184 | } |
185 | EC_GROUP_set_asn1_flag(smctx->gen_group, p1); |
186 | return 1; |
187 | |
188 | case EVP_PKEY_CTRL_MD: |
189 | smctx->md = p2; |
190 | return 1; |
191 | |
192 | case EVP_PKEY_CTRL_GET_MD: |
193 | *(const EVP_MD **)p2 = smctx->md; |
194 | return 1; |
195 | |
196 | case EVP_PKEY_CTRL_SET1_ID: |
197 | if (p1 > 0) { |
198 | tmp_id = OPENSSL_malloc(p1); |
199 | if (tmp_id == NULL) { |
200 | SM2err(SM2_F_PKEY_SM2_CTRL, ERR_R_MALLOC_FAILURE); |
201 | return 0; |
202 | } |
203 | memcpy(tmp_id, p2, p1); |
204 | OPENSSL_free(smctx->id); |
205 | smctx->id = tmp_id; |
206 | } else { |
207 | /* set null-ID */ |
208 | OPENSSL_free(smctx->id); |
209 | smctx->id = NULL; |
210 | } |
211 | smctx->id_len = (size_t)p1; |
212 | smctx->id_set = 1; |
213 | return 1; |
214 | |
215 | case EVP_PKEY_CTRL_GET1_ID: |
216 | memcpy(p2, smctx->id, smctx->id_len); |
217 | return 1; |
218 | |
219 | case EVP_PKEY_CTRL_GET1_ID_LEN: |
220 | *(size_t *)p2 = smctx->id_len; |
221 | return 1; |
222 | |
223 | case EVP_PKEY_CTRL_DIGESTINIT: |
224 | /* nothing to be inited, this is to suppress the error... */ |
225 | return 1; |
226 | |
227 | default: |
228 | return -2; |
229 | } |
230 | } |
231 | |
232 | static int pkey_sm2_ctrl_str(EVP_PKEY_CTX *ctx, |
233 | const char *type, const char *value) |
234 | { |
235 | uint8_t *hex_id; |
236 | long hex_len = 0; |
237 | int ret = 0; |
238 | |
239 | if (strcmp(type, "ec_paramgen_curve" ) == 0) { |
240 | int nid = NID_undef; |
241 | |
242 | if (((nid = EC_curve_nist2nid(value)) == NID_undef) |
243 | && ((nid = OBJ_sn2nid(value)) == NID_undef) |
244 | && ((nid = OBJ_ln2nid(value)) == NID_undef)) { |
245 | SM2err(SM2_F_PKEY_SM2_CTRL_STR, SM2_R_INVALID_CURVE); |
246 | return 0; |
247 | } |
248 | return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx, nid); |
249 | } else if (strcmp(type, "ec_param_enc" ) == 0) { |
250 | int param_enc; |
251 | |
252 | if (strcmp(value, "explicit" ) == 0) |
253 | param_enc = 0; |
254 | else if (strcmp(value, "named_curve" ) == 0) |
255 | param_enc = OPENSSL_EC_NAMED_CURVE; |
256 | else |
257 | return -2; |
258 | return EVP_PKEY_CTX_set_ec_param_enc(ctx, param_enc); |
259 | } else if (strcmp(type, "sm2_id" ) == 0) { |
260 | return pkey_sm2_ctrl(ctx, EVP_PKEY_CTRL_SET1_ID, |
261 | (int)strlen(value), (void *)value); |
262 | } else if (strcmp(type, "sm2_hex_id" ) == 0) { |
263 | /* |
264 | * TODO(3.0): reconsider the name "sm2_hex_id", OR change |
265 | * OSSL_PARAM_construct_from_text() / OSSL_PARAM_allocate_from_text() |
266 | * to handle infix "_hex_" |
267 | */ |
268 | hex_id = OPENSSL_hexstr2buf((const char *)value, &hex_len); |
269 | if (hex_id == NULL) { |
270 | SM2err(SM2_F_PKEY_SM2_CTRL_STR, ERR_R_PASSED_INVALID_ARGUMENT); |
271 | return 0; |
272 | } |
273 | ret = pkey_sm2_ctrl(ctx, EVP_PKEY_CTRL_SET1_ID, (int)hex_len, |
274 | (void *)hex_id); |
275 | OPENSSL_free(hex_id); |
276 | return ret; |
277 | } |
278 | |
279 | return -2; |
280 | } |
281 | |
282 | static int pkey_sm2_digest_custom(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx) |
283 | { |
284 | uint8_t z[EVP_MAX_MD_SIZE]; |
285 | SM2_PKEY_CTX *smctx = ctx->data; |
286 | EC_KEY *ec = ctx->pkey->pkey.ec; |
287 | const EVP_MD *md = EVP_MD_CTX_md(mctx); |
288 | int mdlen = EVP_MD_size(md); |
289 | |
290 | if (!smctx->id_set) { |
291 | /* |
292 | * An ID value must be set. The specifications are not clear whether a |
293 | * NULL is allowed. We only allow it if set explicitly for maximum |
294 | * flexibility. |
295 | */ |
296 | SM2err(SM2_F_PKEY_SM2_DIGEST_CUSTOM, SM2_R_ID_NOT_SET); |
297 | return 0; |
298 | } |
299 | |
300 | if (mdlen < 0) { |
301 | SM2err(SM2_F_PKEY_SM2_DIGEST_CUSTOM, SM2_R_INVALID_DIGEST); |
302 | return 0; |
303 | } |
304 | |
305 | /* get hashed prefix 'z' of tbs message */ |
306 | if (!sm2_compute_z_digest(z, md, smctx->id, smctx->id_len, ec)) |
307 | return 0; |
308 | |
309 | return EVP_DigestUpdate(mctx, z, (size_t)mdlen); |
310 | } |
311 | |
312 | static const EVP_PKEY_METHOD sm2_pkey_meth = { |
313 | EVP_PKEY_SM2, |
314 | 0, |
315 | pkey_sm2_init, |
316 | pkey_sm2_copy, |
317 | pkey_sm2_cleanup, |
318 | |
319 | 0, |
320 | 0, |
321 | |
322 | 0, |
323 | 0, |
324 | |
325 | 0, |
326 | pkey_sm2_sign, |
327 | |
328 | 0, |
329 | pkey_sm2_verify, |
330 | |
331 | 0, 0, |
332 | |
333 | 0, 0, 0, 0, |
334 | |
335 | 0, |
336 | pkey_sm2_encrypt, |
337 | |
338 | 0, |
339 | pkey_sm2_decrypt, |
340 | |
341 | 0, |
342 | 0, |
343 | pkey_sm2_ctrl, |
344 | pkey_sm2_ctrl_str, |
345 | |
346 | 0, 0, |
347 | |
348 | 0, 0, 0, |
349 | |
350 | pkey_sm2_digest_custom |
351 | }; |
352 | |
353 | const EVP_PKEY_METHOD *sm2_pkey_method(void) |
354 | { |
355 | return &sm2_pkey_meth; |
356 | } |
357 | |