1 /*
2 * Copyright 2006-2023 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 <assert.h>
11 #include <openssl/cms.h>
12 #include <openssl/err.h>
13 #include <openssl/core_names.h>
14 #include "crypto/asn1.h"
15 #include "crypto/rsa.h"
16 #include "crypto/evp.h"
17 #include "cms_local.h"
18
rsa_oaep_decode(const X509_ALGOR * alg)19 static RSA_OAEP_PARAMS *rsa_oaep_decode(const X509_ALGOR *alg)
20 {
21 RSA_OAEP_PARAMS *oaep;
22
23 oaep = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(RSA_OAEP_PARAMS),
24 alg->parameter);
25
26 if (oaep == NULL)
27 return NULL;
28
29 if (oaep->maskGenFunc != NULL) {
30 oaep->maskHash = ossl_x509_algor_mgf1_decode(oaep->maskGenFunc);
31 if (oaep->maskHash == NULL) {
32 RSA_OAEP_PARAMS_free(oaep);
33 return NULL;
34 }
35 }
36 return oaep;
37 }
38
rsa_cms_decrypt(CMS_RecipientInfo * ri)39 static int rsa_cms_decrypt(CMS_RecipientInfo *ri)
40 {
41 EVP_PKEY_CTX *pkctx;
42 X509_ALGOR *cmsalg;
43 int nid;
44 int rv = -1;
45 unsigned char *label = NULL;
46 int labellen = 0;
47 const EVP_MD *mgf1md = NULL, *md = NULL;
48 RSA_OAEP_PARAMS *oaep;
49
50 pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
51 if (pkctx == NULL)
52 return 0;
53 if (!CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &cmsalg))
54 return -1;
55 nid = OBJ_obj2nid(cmsalg->algorithm);
56 if (nid == NID_rsaEncryption)
57 return 1;
58 if (nid != NID_rsaesOaep) {
59 ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_ENCRYPTION_TYPE);
60 return -1;
61 }
62 /* Decode OAEP parameters */
63 oaep = rsa_oaep_decode(cmsalg);
64
65 if (oaep == NULL) {
66 ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_OAEP_PARAMETERS);
67 goto err;
68 }
69
70 mgf1md = ossl_x509_algor_get_md(oaep->maskHash);
71 if (mgf1md == NULL)
72 goto err;
73 md = ossl_x509_algor_get_md(oaep->hashFunc);
74 if (md == NULL)
75 goto err;
76
77 if (oaep->pSourceFunc != NULL) {
78 X509_ALGOR *plab = oaep->pSourceFunc;
79
80 if (OBJ_obj2nid(plab->algorithm) != NID_pSpecified) {
81 ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_LABEL_SOURCE);
82 goto err;
83 }
84 if (plab->parameter->type != V_ASN1_OCTET_STRING) {
85 ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_LABEL);
86 goto err;
87 }
88
89 label = plab->parameter->value.octet_string->data;
90 /* Stop label being freed when OAEP parameters are freed */
91 plab->parameter->value.octet_string->data = NULL;
92 labellen = plab->parameter->value.octet_string->length;
93 }
94
95 if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_OAEP_PADDING) <= 0)
96 goto err;
97 if (EVP_PKEY_CTX_set_rsa_oaep_md(pkctx, md) <= 0)
98 goto err;
99 if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
100 goto err;
101 if (label != NULL
102 && EVP_PKEY_CTX_set0_rsa_oaep_label(pkctx, label, labellen) <= 0) {
103 OPENSSL_free(label);
104 goto err;
105 }
106 /* Carry on */
107 rv = 1;
108
109 err:
110 RSA_OAEP_PARAMS_free(oaep);
111 return rv;
112 }
113
rsa_cms_encrypt(CMS_RecipientInfo * ri)114 static int rsa_cms_encrypt(CMS_RecipientInfo *ri)
115 {
116 const EVP_MD *md, *mgf1md;
117 RSA_OAEP_PARAMS *oaep = NULL;
118 ASN1_STRING *os = NULL;
119 ASN1_OCTET_STRING *los = NULL;
120 X509_ALGOR *alg;
121 EVP_PKEY_CTX *pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
122 int pad_mode = RSA_PKCS1_PADDING, rv = 0, labellen;
123 unsigned char *label;
124
125 if (CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &alg) <= 0)
126 return 0;
127 if (pkctx != NULL) {
128 if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
129 return 0;
130 }
131 if (pad_mode == RSA_PKCS1_PADDING)
132 return X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption),
133 V_ASN1_NULL, NULL);
134
135 /* Not supported */
136 if (pad_mode != RSA_PKCS1_OAEP_PADDING)
137 return 0;
138 if (EVP_PKEY_CTX_get_rsa_oaep_md(pkctx, &md) <= 0)
139 goto err;
140 if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
141 goto err;
142 labellen = EVP_PKEY_CTX_get0_rsa_oaep_label(pkctx, &label);
143 if (labellen < 0)
144 goto err;
145 oaep = RSA_OAEP_PARAMS_new();
146 if (oaep == NULL)
147 goto err;
148 if (!ossl_x509_algor_new_from_md(&oaep->hashFunc, md))
149 goto err;
150 if (!ossl_x509_algor_md_to_mgf1(&oaep->maskGenFunc, mgf1md))
151 goto err;
152 if (labellen > 0) {
153 oaep->pSourceFunc = X509_ALGOR_new();
154 if (oaep->pSourceFunc == NULL)
155 goto err;
156 los = ASN1_OCTET_STRING_new();
157 if (los == NULL)
158 goto err;
159 if (!ASN1_OCTET_STRING_set(los, label, labellen))
160 goto err;
161
162 if (!X509_ALGOR_set0(oaep->pSourceFunc, OBJ_nid2obj(NID_pSpecified),
163 V_ASN1_OCTET_STRING, los))
164 goto err;
165
166 los = NULL;
167 }
168 /* create string with oaep parameter encoding. */
169 if (!ASN1_item_pack(oaep, ASN1_ITEM_rptr(RSA_OAEP_PARAMS), &os))
170 goto err;
171 if (!X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaesOaep), V_ASN1_SEQUENCE, os))
172 goto err;
173 os = NULL;
174 rv = 1;
175 err:
176 RSA_OAEP_PARAMS_free(oaep);
177 ASN1_STRING_free(os);
178 ASN1_OCTET_STRING_free(los);
179 return rv;
180 }
181
ossl_cms_rsa_envelope(CMS_RecipientInfo * ri,int decrypt)182 int ossl_cms_rsa_envelope(CMS_RecipientInfo *ri, int decrypt)
183 {
184 assert(decrypt == 0 || decrypt == 1);
185
186 if (decrypt == 1)
187 return rsa_cms_decrypt(ri);
188
189 if (decrypt == 0)
190 return rsa_cms_encrypt(ri);
191
192 ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
193 return 0;
194 }
195
rsa_cms_sign(CMS_SignerInfo * si)196 static int rsa_cms_sign(CMS_SignerInfo *si)
197 {
198 int pad_mode = RSA_PKCS1_PADDING;
199 X509_ALGOR *alg;
200 EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
201 unsigned char aid[128];
202 const unsigned char *pp = aid;
203 size_t aid_len = 0;
204 OSSL_PARAM params[2];
205
206 CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
207 if (pkctx != NULL) {
208 if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
209 return 0;
210 }
211 if (pad_mode == RSA_PKCS1_PADDING) {
212 X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
213 return 1;
214 }
215 /* We don't support it */
216 if (pad_mode != RSA_PKCS1_PSS_PADDING)
217 return 0;
218
219 if (evp_pkey_ctx_is_legacy(pkctx)) {
220 /* No provider -> we cannot query it for algorithm ID. */
221 ASN1_STRING *os = NULL;
222
223 os = ossl_rsa_ctx_to_pss_string(pkctx);
224 if (os == NULL)
225 return 0;
226 return X509_ALGOR_set0(alg, OBJ_nid2obj(EVP_PKEY_RSA_PSS), V_ASN1_SEQUENCE, os);
227 }
228
229 params[0] = OSSL_PARAM_construct_octet_string(
230 OSSL_SIGNATURE_PARAM_ALGORITHM_ID, aid, sizeof(aid));
231 params[1] = OSSL_PARAM_construct_end();
232
233 if (EVP_PKEY_CTX_get_params(pkctx, params) <= 0)
234 return 0;
235 if ((aid_len = params[0].return_size) == 0)
236 return 0;
237 if (d2i_X509_ALGOR(&alg, &pp, aid_len) == NULL)
238 return 0;
239 return 1;
240 }
241
rsa_cms_verify(CMS_SignerInfo * si)242 static int rsa_cms_verify(CMS_SignerInfo *si)
243 {
244 int nid, nid2;
245 X509_ALGOR *alg;
246 EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
247 EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(pkctx);
248
249 CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
250 nid = OBJ_obj2nid(alg->algorithm);
251 if (nid == EVP_PKEY_RSA_PSS)
252 return ossl_rsa_pss_to_ctx(NULL, pkctx, alg, NULL) > 0;
253 /* Only PSS allowed for PSS keys */
254 if (EVP_PKEY_is_a(pkey, "RSA-PSS")) {
255 ERR_raise(ERR_LIB_RSA, RSA_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
256 return 0;
257 }
258 if (nid == NID_rsaEncryption)
259 return 1;
260 /* Workaround for some implementation that use a signature OID */
261 if (OBJ_find_sigid_algs(nid, NULL, &nid2)) {
262 if (nid2 == NID_rsaEncryption)
263 return 1;
264 }
265 return 0;
266 }
267
ossl_cms_rsa_sign(CMS_SignerInfo * si,int verify)268 int ossl_cms_rsa_sign(CMS_SignerInfo *si, int verify)
269 {
270 assert(verify == 0 || verify == 1);
271
272 if (verify == 1)
273 return rsa_cms_verify(si);
274
275 if (verify == 0)
276 return rsa_cms_sign(si);
277
278 ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
279 return 0;
280 }
281