1 /*
2 * Copyright 2020-2022 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 /*
11 * RSA low level APIs are deprecated for public use, but still ok for
12 * internal use.
13 */
14 #include "internal/deprecated.h"
15
16 #include <string.h>
17
18 #include <openssl/core_dispatch.h>
19 #include <openssl/core_names.h>
20 #include <openssl/core_object.h>
21 #include <openssl/crypto.h>
22 #include <openssl/err.h>
23 #include <openssl/params.h>
24 #include <openssl/pem.h>
25 #include <openssl/proverr.h>
26 #include "internal/nelem.h"
27 #include "prov/bio.h"
28 #include "prov/implementations.h"
29 #include "endecoder_local.h"
30
read_pem(PROV_CTX * provctx,OSSL_CORE_BIO * cin,char ** pem_name,char ** pem_header,unsigned char ** data,long * len)31 static int read_pem(PROV_CTX *provctx, OSSL_CORE_BIO *cin,
32 char **pem_name, char **pem_header,
33 unsigned char **data, long *len)
34 {
35 BIO *in = ossl_bio_new_from_core_bio(provctx, cin);
36 int ok;
37
38 if (in == NULL)
39 return 0;
40 ok = (PEM_read_bio(in, pem_name, pem_header, data, len) > 0);
41
42 BIO_free(in);
43 return ok;
44 }
45
46 static OSSL_FUNC_decoder_newctx_fn pem2der_newctx;
47 static OSSL_FUNC_decoder_freectx_fn pem2der_freectx;
48 static OSSL_FUNC_decoder_decode_fn pem2der_decode;
49
50 /*
51 * Context used for PEM to DER decoding.
52 */
53 struct pem2der_ctx_st {
54 PROV_CTX *provctx;
55 };
56
pem2der_newctx(void * provctx)57 static void *pem2der_newctx(void *provctx)
58 {
59 struct pem2der_ctx_st *ctx = OPENSSL_zalloc(sizeof(*ctx));
60
61 if (ctx != NULL)
62 ctx->provctx = provctx;
63 return ctx;
64 }
65
pem2der_freectx(void * vctx)66 static void pem2der_freectx(void *vctx)
67 {
68 struct pem2der_ctx_st *ctx = vctx;
69
70 OPENSSL_free(ctx);
71 }
72
73 /* pem_password_cb compatible function */
74 struct pem2der_pass_data_st {
75 OSSL_PASSPHRASE_CALLBACK *cb;
76 void *cbarg;
77 };
78
pem2der_pass_helper(char * buf,int num,int w,void * data)79 static int pem2der_pass_helper(char *buf, int num, int w, void *data)
80 {
81 struct pem2der_pass_data_st *pass_data = data;
82 size_t plen;
83
84 if (pass_data == NULL
85 || pass_data->cb == NULL
86 || !pass_data->cb(buf, num, &plen, NULL, pass_data->cbarg))
87 return -1;
88 return (int)plen;
89 }
90
91 /*
92 * The selection parameter in pem2der_decode() is not used by this function
93 * because it's not relevant just to decode PEM to DER.
94 */
pem2der_decode(void * vctx,OSSL_CORE_BIO * cin,int selection,OSSL_CALLBACK * data_cb,void * data_cbarg,OSSL_PASSPHRASE_CALLBACK * pw_cb,void * pw_cbarg)95 static int pem2der_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
96 OSSL_CALLBACK *data_cb, void *data_cbarg,
97 OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
98 {
99 /*
100 * PEM names we recognise. Other PEM names should be recognised by
101 * other decoder implementations.
102 */
103 static struct pem_name_map_st {
104 const char *pem_name;
105 int object_type;
106 const char *data_type;
107 const char *data_structure;
108 } pem_name_map[] = {
109 /* PKCS#8 and SubjectPublicKeyInfo */
110 { PEM_STRING_PKCS8, OSSL_OBJECT_PKEY, NULL, "EncryptedPrivateKeyInfo" },
111 { PEM_STRING_PKCS8INF, OSSL_OBJECT_PKEY, NULL, "PrivateKeyInfo" },
112 { PEM_STRING_PUBLIC, OSSL_OBJECT_PKEY, NULL, "SubjectPublicKeyInfo" },
113
114 /* Our set of type specific PEM types */
115 { PEM_STRING_DHPARAMS, OSSL_OBJECT_PKEY, "DH", "type-specific" },
116 { PEM_STRING_DHXPARAMS, OSSL_OBJECT_PKEY, "X9.42 DH", "type-specific" },
117 { PEM_STRING_DSA, OSSL_OBJECT_PKEY, "DSA", "type-specific" },
118 { PEM_STRING_DSA_PUBLIC, OSSL_OBJECT_PKEY, "DSA", "type-specific" },
119 { PEM_STRING_DSAPARAMS, OSSL_OBJECT_PKEY, "DSA", "type-specific" },
120 { PEM_STRING_ECPRIVATEKEY, OSSL_OBJECT_PKEY, "EC", "type-specific" },
121 { PEM_STRING_ECPARAMETERS, OSSL_OBJECT_PKEY, "EC", "type-specific" },
122 { PEM_STRING_RSA, OSSL_OBJECT_PKEY, "RSA", "type-specific" },
123 { PEM_STRING_RSA_PUBLIC, OSSL_OBJECT_PKEY, "RSA", "type-specific" },
124
125 /*
126 * A few others that there is at least have an object type for, even
127 * though there is no provider interface to handle such objects, yet.
128 * However, this is beneficial for the OSSL_STORE result handler.
129 */
130 { PEM_STRING_X509, OSSL_OBJECT_CERT, NULL, "Certificate" },
131 { PEM_STRING_X509_TRUSTED, OSSL_OBJECT_CERT, NULL, "Certificate" },
132 { PEM_STRING_X509_OLD, OSSL_OBJECT_CERT, NULL, "Certificate" },
133 { PEM_STRING_X509_CRL, OSSL_OBJECT_CRL, NULL, "CertificateList" }
134 };
135 struct pem2der_ctx_st *ctx = vctx;
136 char *pem_name = NULL, *pem_header = NULL;
137 size_t i;
138 unsigned char *der = NULL;
139 long der_len = 0;
140 int ok = 0;
141 int objtype = OSSL_OBJECT_UNKNOWN;
142
143 ok = read_pem(ctx->provctx, cin, &pem_name, &pem_header,
144 &der, &der_len) > 0;
145 /* We return "empty handed". This is not an error. */
146 if (!ok)
147 return 1;
148
149 /*
150 * 10 is the number of characters in "Proc-Type:", which
151 * PEM_get_EVP_CIPHER_INFO() requires to be present.
152 * If the PEM header has less characters than that, it's
153 * not worth spending cycles on it.
154 */
155 if (strlen(pem_header) > 10) {
156 EVP_CIPHER_INFO cipher;
157 struct pem2der_pass_data_st pass_data;
158
159 ok = 0; /* Assume that we fail */
160 pass_data.cb = pw_cb;
161 pass_data.cbarg = pw_cbarg;
162 if (!PEM_get_EVP_CIPHER_INFO(pem_header, &cipher)
163 || !PEM_do_header(&cipher, der, &der_len,
164 pem2der_pass_helper, &pass_data))
165 goto end;
166 }
167
168 /*
169 * Indicated that we successfully decoded something, or not at all.
170 * Ending up "empty handed" is not an error.
171 */
172 ok = 1;
173
174 /* Have a look to see if we recognise anything */
175 for (i = 0; i < OSSL_NELEM(pem_name_map); i++)
176 if (strcmp(pem_name, pem_name_map[i].pem_name) == 0)
177 break;
178
179 if (i < OSSL_NELEM(pem_name_map)) {
180 OSSL_PARAM params[5], *p = params;
181 /* We expect these to be read only so casting away the const is ok */
182 char *data_type = (char *)pem_name_map[i].data_type;
183 char *data_structure = (char *)pem_name_map[i].data_structure;
184
185 objtype = pem_name_map[i].object_type;
186 if (data_type != NULL)
187 *p++ =
188 OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
189 data_type, 0);
190
191 /* We expect this to be read only so casting away the const is ok */
192 if (data_structure != NULL)
193 *p++ =
194 OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_STRUCTURE,
195 data_structure, 0);
196 *p++ =
197 OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_DATA,
198 der, der_len);
199 *p++ =
200 OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &objtype);
201
202 *p = OSSL_PARAM_construct_end();
203
204 ok = data_cb(params, data_cbarg);
205 }
206
207 end:
208 OPENSSL_free(pem_name);
209 OPENSSL_free(pem_header);
210 OPENSSL_free(der);
211 return ok;
212 }
213
214 const OSSL_DISPATCH ossl_pem_to_der_decoder_functions[] = {
215 { OSSL_FUNC_DECODER_NEWCTX, (void (*)(void))pem2der_newctx },
216 { OSSL_FUNC_DECODER_FREECTX, (void (*)(void))pem2der_freectx },
217 { OSSL_FUNC_DECODER_DECODE, (void (*)(void))pem2der_decode },
218 { 0, NULL }
219 };
220