1 /*
2 * Copyright 2006-2021 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 <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 "cms_local.h"
17
rsa_oaep_decode(const X509_ALGOR * alg)18 static RSA_OAEP_PARAMS *rsa_oaep_decode(const X509_ALGOR *alg)
19 {
20 RSA_OAEP_PARAMS *oaep;
21
22 oaep = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(RSA_OAEP_PARAMS),
23 alg->parameter);
24
25 if (oaep == NULL)
26 return NULL;
27
28 if (oaep->maskGenFunc != NULL) {
29 oaep->maskHash = ossl_x509_algor_mgf1_decode(oaep->maskGenFunc);
30 if (oaep->maskHash == NULL) {
31 RSA_OAEP_PARAMS_free(oaep);
32 return NULL;
33 }
34 }
35 return oaep;
36 }
37
rsa_cms_decrypt(CMS_RecipientInfo * ri)38 static int rsa_cms_decrypt(CMS_RecipientInfo *ri)
39 {
40 EVP_PKEY_CTX *pkctx;
41 X509_ALGOR *cmsalg;
42 int nid;
43 int rv = -1;
44 unsigned char *label = NULL;
45 int labellen = 0;
46 const EVP_MD *mgf1md = NULL, *md = NULL;
47 RSA_OAEP_PARAMS *oaep;
48
49 pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
50 if (pkctx == NULL)
51 return 0;
52 if (!CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &cmsalg))
53 return -1;
54 nid = OBJ_obj2nid(cmsalg->algorithm);
55 if (nid == NID_rsaEncryption)
56 return 1;
57 if (nid != NID_rsaesOaep) {
58 ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_ENCRYPTION_TYPE);
59 return -1;
60 }
61 /* Decode OAEP parameters */
62 oaep = rsa_oaep_decode(cmsalg);
63
64 if (oaep == NULL) {
65 ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_OAEP_PARAMETERS);
66 goto err;
67 }
68
69 mgf1md = ossl_x509_algor_get_md(oaep->maskHash);
70 if (mgf1md == NULL)
71 goto err;
72 md = ossl_x509_algor_get_md(oaep->hashFunc);
73 if (md == NULL)
74 goto err;
75
76 if (oaep->pSourceFunc != NULL) {
77 X509_ALGOR *plab = oaep->pSourceFunc;
78
79 if (OBJ_obj2nid(plab->algorithm) != NID_pSpecified) {
80 ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_LABEL_SOURCE);
81 goto err;
82 }
83 if (plab->parameter->type != V_ASN1_OCTET_STRING) {
84 ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_LABEL);
85 goto err;
86 }
87
88 label = plab->parameter->value.octet_string->data;
89 /* Stop label being freed when OAEP parameters are freed */
90 plab->parameter->value.octet_string->data = NULL;
91 labellen = plab->parameter->value.octet_string->length;
92 }
93
94 if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_OAEP_PADDING) <= 0)
95 goto err;
96 if (EVP_PKEY_CTX_set_rsa_oaep_md(pkctx, md) <= 0)
97 goto err;
98 if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
99 goto err;
100 if (label != NULL
101 && EVP_PKEY_CTX_set0_rsa_oaep_label(pkctx, label, labellen) <= 0)
102 goto err;
103 /* Carry on */
104 rv = 1;
105
106 err:
107 RSA_OAEP_PARAMS_free(oaep);
108 return rv;
109 }
110
rsa_cms_encrypt(CMS_RecipientInfo * ri)111 static int rsa_cms_encrypt(CMS_RecipientInfo *ri)
112 {
113 const EVP_MD *md, *mgf1md;
114 RSA_OAEP_PARAMS *oaep = NULL;
115 ASN1_STRING *os = NULL;
116 X509_ALGOR *alg;
117 EVP_PKEY_CTX *pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
118 int pad_mode = RSA_PKCS1_PADDING, rv = 0, labellen;
119 unsigned char *label;
120
121 if (CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &alg) <= 0)
122 return 0;
123 if (pkctx != NULL) {
124 if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
125 return 0;
126 }
127 if (pad_mode == RSA_PKCS1_PADDING) {
128 X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
129 return 1;
130 }
131 /* Not supported */
132 if (pad_mode != RSA_PKCS1_OAEP_PADDING)
133 return 0;
134 if (EVP_PKEY_CTX_get_rsa_oaep_md(pkctx, &md) <= 0)
135 goto err;
136 if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
137 goto err;
138 labellen = EVP_PKEY_CTX_get0_rsa_oaep_label(pkctx, &label);
139 if (labellen < 0)
140 goto err;
141 oaep = RSA_OAEP_PARAMS_new();
142 if (oaep == NULL)
143 goto err;
144 if (!ossl_x509_algor_new_from_md(&oaep->hashFunc, md))
145 goto err;
146 if (!ossl_x509_algor_md_to_mgf1(&oaep->maskGenFunc, mgf1md))
147 goto err;
148 if (labellen > 0) {
149 ASN1_OCTET_STRING *los;
150
151 oaep->pSourceFunc = X509_ALGOR_new();
152 if (oaep->pSourceFunc == NULL)
153 goto err;
154 los = ASN1_OCTET_STRING_new();
155 if (los == NULL)
156 goto err;
157 if (!ASN1_OCTET_STRING_set(los, label, labellen)) {
158 ASN1_OCTET_STRING_free(los);
159 goto err;
160 }
161 X509_ALGOR_set0(oaep->pSourceFunc, OBJ_nid2obj(NID_pSpecified),
162 V_ASN1_OCTET_STRING, los);
163 }
164 /* create string with pss parameter encoding. */
165 if (!ASN1_item_pack(oaep, ASN1_ITEM_rptr(RSA_OAEP_PARAMS), &os))
166 goto err;
167 X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaesOaep), V_ASN1_SEQUENCE, os);
168 os = NULL;
169 rv = 1;
170 err:
171 RSA_OAEP_PARAMS_free(oaep);
172 ASN1_STRING_free(os);
173 return rv;
174 }
175
ossl_cms_rsa_envelope(CMS_RecipientInfo * ri,int decrypt)176 int ossl_cms_rsa_envelope(CMS_RecipientInfo *ri, int decrypt)
177 {
178 assert(decrypt == 0 || decrypt == 1);
179
180 if (decrypt == 1)
181 return rsa_cms_decrypt(ri);
182
183 if (decrypt == 0)
184 return rsa_cms_encrypt(ri);
185
186 ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
187 return 0;
188 }
189
rsa_cms_sign(CMS_SignerInfo * si)190 static int rsa_cms_sign(CMS_SignerInfo *si)
191 {
192 int pad_mode = RSA_PKCS1_PADDING;
193 X509_ALGOR *alg;
194 EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
195 unsigned char aid[128];
196 const unsigned char *pp = aid;
197 size_t aid_len = 0;
198 OSSL_PARAM params[2];
199
200 CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
201 if (pkctx != NULL) {
202 if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
203 return 0;
204 }
205 if (pad_mode == RSA_PKCS1_PADDING) {
206 X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
207 return 1;
208 }
209 /* We don't support it */
210 if (pad_mode != RSA_PKCS1_PSS_PADDING)
211 return 0;
212
213 params[0] = OSSL_PARAM_construct_octet_string(
214 OSSL_SIGNATURE_PARAM_ALGORITHM_ID, aid, sizeof(aid));
215 params[1] = OSSL_PARAM_construct_end();
216
217 if (EVP_PKEY_CTX_get_params(pkctx, params) <= 0)
218 return 0;
219 if ((aid_len = params[0].return_size) == 0)
220 return 0;
221 if (d2i_X509_ALGOR(&alg, &pp, aid_len) == NULL)
222 return 0;
223 return 1;
224 }
225
rsa_cms_verify(CMS_SignerInfo * si)226 static int rsa_cms_verify(CMS_SignerInfo *si)
227 {
228 int nid, nid2;
229 X509_ALGOR *alg;
230 EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
231 EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(pkctx);
232
233 CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
234 nid = OBJ_obj2nid(alg->algorithm);
235 if (nid == EVP_PKEY_RSA_PSS)
236 return ossl_rsa_pss_to_ctx(NULL, pkctx, alg, NULL) > 0;
237 /* Only PSS allowed for PSS keys */
238 if (EVP_PKEY_is_a(pkey, "RSA-PSS")) {
239 ERR_raise(ERR_LIB_RSA, RSA_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
240 return 0;
241 }
242 if (nid == NID_rsaEncryption)
243 return 1;
244 /* Workaround for some implementation that use a signature OID */
245 if (OBJ_find_sigid_algs(nid, NULL, &nid2)) {
246 if (nid2 == NID_rsaEncryption)
247 return 1;
248 }
249 return 0;
250 }
251
ossl_cms_rsa_sign(CMS_SignerInfo * si,int verify)252 int ossl_cms_rsa_sign(CMS_SignerInfo *si, int verify)
253 {
254 assert(verify == 0 || verify == 1);
255
256 if (verify == 1)
257 return rsa_cms_verify(si);
258
259 if (verify == 0)
260 return rsa_cms_sign(si);
261
262 ERR_raise(ERR_LIB_CMS, CMS_R_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
263 return 0;
264 }
265