1 /*
2 * Copyright 2020-2023 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 /*
11 * 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/params.h>
23 #include <openssl/pem.h> /* For public PVK functions */
24 #include <openssl/x509.h>
25 #include <openssl/err.h>
26 #include "internal/passphrase.h"
27 #include "crypto/pem.h" /* For internal PVK and "blob" headers */
28 #include "crypto/rsa.h"
29 #include "prov/bio.h"
30 #include "prov/implementations.h"
31 #include "endecoder_local.h"
32
33 struct msblob2key_ctx_st; /* Forward declaration */
34 typedef void *b2i_of_void_fn(const unsigned char **in, unsigned int bitlen,
35 int ispub);
36 typedef void adjust_key_fn(void *, struct msblob2key_ctx_st *ctx);
37 typedef void free_key_fn(void *);
38 struct keytype_desc_st {
39 int type; /* EVP key type */
40 const char *name; /* Keytype */
41 const OSSL_DISPATCH *fns; /* Keymgmt (to pilfer functions from) */
42
43 b2i_of_void_fn *read_private_key;
44 b2i_of_void_fn *read_public_key;
45 adjust_key_fn *adjust_key;
46 free_key_fn *free_key;
47 };
48
49 static OSSL_FUNC_decoder_freectx_fn msblob2key_freectx;
50 static OSSL_FUNC_decoder_decode_fn msblob2key_decode;
51 static OSSL_FUNC_decoder_export_object_fn msblob2key_export_object;
52
53 /*
54 * Context used for DER to key decoding.
55 */
56 struct msblob2key_ctx_st {
57 PROV_CTX *provctx;
58 const struct keytype_desc_st *desc;
59 /* The selection that is passed to msblob2key_decode() */
60 int selection;
61 };
62
63 static struct msblob2key_ctx_st *
msblob2key_newctx(void * provctx,const struct keytype_desc_st * desc)64 msblob2key_newctx(void *provctx, const struct keytype_desc_st *desc)
65 {
66 struct msblob2key_ctx_st *ctx = OPENSSL_zalloc(sizeof(*ctx));
67
68 if (ctx != NULL) {
69 ctx->provctx = provctx;
70 ctx->desc = desc;
71 }
72 return ctx;
73 }
74
msblob2key_freectx(void * vctx)75 static void msblob2key_freectx(void *vctx)
76 {
77 struct msblob2key_ctx_st *ctx = vctx;
78
79 OPENSSL_free(ctx);
80 }
81
msblob2key_does_selection(void * provctx,int selection)82 static int msblob2key_does_selection(void *provctx, int selection)
83 {
84 if (selection == 0)
85 return 1;
86
87 if ((selection & (OSSL_KEYMGMT_SELECT_PRIVATE_KEY
88 | OSSL_KEYMGMT_SELECT_PUBLIC_KEY)) != 0)
89 return 1;
90
91 return 0;
92 }
93
msblob2key_decode(void * vctx,OSSL_CORE_BIO * cin,int selection,OSSL_CALLBACK * data_cb,void * data_cbarg,OSSL_PASSPHRASE_CALLBACK * pw_cb,void * pw_cbarg)94 static int msblob2key_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
95 OSSL_CALLBACK *data_cb, void *data_cbarg,
96 OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
97 {
98 struct msblob2key_ctx_st *ctx = vctx;
99 BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
100 const unsigned char *p;
101 unsigned char hdr_buf[16], *buf = NULL;
102 unsigned int bitlen, magic, length;
103 int isdss = -1;
104 int ispub = -1;
105 void *key = NULL;
106 int ok = 0;
107
108 if (in == NULL)
109 return 0;
110
111 if (BIO_read(in, hdr_buf, 16) != 16) {
112 ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
113 goto next;
114 }
115 ERR_set_mark();
116 p = hdr_buf;
117 ok = ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) > 0;
118 ERR_pop_to_mark();
119 if (!ok)
120 goto next;
121
122 ctx->selection = selection;
123 ok = 0; /* Assume that we fail */
124
125 if ((isdss && ctx->desc->type != EVP_PKEY_DSA)
126 || (!isdss && ctx->desc->type != EVP_PKEY_RSA))
127 goto next;
128
129 length = ossl_blob_length(bitlen, isdss, ispub);
130 if (length > BLOB_MAX_LENGTH) {
131 ERR_raise(ERR_LIB_PEM, PEM_R_HEADER_TOO_LONG);
132 goto next;
133 }
134 buf = OPENSSL_malloc(length);
135 if (buf == NULL)
136 goto end;
137 p = buf;
138 if (BIO_read(in, buf, length) != (int)length) {
139 ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
140 goto next;
141 }
142
143 if ((selection == 0
144 || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
145 && !ispub
146 && ctx->desc->read_private_key != NULL) {
147 struct ossl_passphrase_data_st pwdata;
148
149 memset(&pwdata, 0, sizeof(pwdata));
150 if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
151 goto end;
152 p = buf;
153 key = ctx->desc->read_private_key(&p, bitlen, ispub);
154 if (selection != 0 && key == NULL)
155 goto next;
156 }
157 if (key == NULL && (selection == 0
158 || (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
159 && ispub
160 && ctx->desc->read_public_key != NULL) {
161 p = buf;
162 key = ctx->desc->read_public_key(&p, bitlen, ispub);
163 if (selection != 0 && key == NULL)
164 goto next;
165 }
166
167 if (key != NULL && ctx->desc->adjust_key != NULL)
168 ctx->desc->adjust_key(key, ctx);
169
170 next:
171 /*
172 * Indicated that we successfully decoded something, or not at all.
173 * Ending up "empty handed" is not an error.
174 */
175 ok = 1;
176
177 /*
178 * We free resources here so it's not held up during the callback, because
179 * we know the process is recursive and the allocated chunks of memory
180 * add up.
181 */
182 OPENSSL_free(buf);
183 BIO_free(in);
184 buf = NULL;
185 in = NULL;
186
187 if (key != NULL) {
188 OSSL_PARAM params[4];
189 int object_type = OSSL_OBJECT_PKEY;
190
191 params[0] =
192 OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
193 params[1] =
194 OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
195 (char *)ctx->desc->name, 0);
196 /* The address of the key becomes the octet string */
197 params[2] =
198 OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
199 &key, sizeof(key));
200 params[3] = OSSL_PARAM_construct_end();
201
202 ok = data_cb(params, data_cbarg);
203 }
204
205 end:
206 BIO_free(in);
207 OPENSSL_free(buf);
208 ctx->desc->free_key(key);
209
210 return ok;
211 }
212
213 static int
msblob2key_export_object(void * vctx,const void * reference,size_t reference_sz,OSSL_CALLBACK * export_cb,void * export_cbarg)214 msblob2key_export_object(void *vctx,
215 const void *reference, size_t reference_sz,
216 OSSL_CALLBACK *export_cb, void *export_cbarg)
217 {
218 struct msblob2key_ctx_st *ctx = vctx;
219 OSSL_FUNC_keymgmt_export_fn *export =
220 ossl_prov_get_keymgmt_export(ctx->desc->fns);
221 void *keydata;
222
223 if (reference_sz == sizeof(keydata) && export != NULL) {
224 int selection = ctx->selection;
225
226 if (selection == 0)
227 selection = OSSL_KEYMGMT_SELECT_ALL;
228 /* The contents of the reference is the address to our object */
229 keydata = *(void **)reference;
230
231 return export(keydata, selection, export_cb, export_cbarg);
232 }
233 return 0;
234 }
235
236 /* ---------------------------------------------------------------------- */
237
238 #define dsa_decode_private_key (b2i_of_void_fn *)ossl_b2i_DSA_after_header
239 #define dsa_decode_public_key (b2i_of_void_fn *)ossl_b2i_DSA_after_header
240 #define dsa_adjust NULL
241 #define dsa_free (void (*)(void *))DSA_free
242
243 /* ---------------------------------------------------------------------- */
244
245 #define rsa_decode_private_key (b2i_of_void_fn *)ossl_b2i_RSA_after_header
246 #define rsa_decode_public_key (b2i_of_void_fn *)ossl_b2i_RSA_after_header
247
rsa_adjust(void * key,struct msblob2key_ctx_st * ctx)248 static void rsa_adjust(void *key, struct msblob2key_ctx_st *ctx)
249 {
250 ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
251 }
252
253 #define rsa_free (void (*)(void *))RSA_free
254
255 /* ---------------------------------------------------------------------- */
256
257 #define IMPLEMENT_MSBLOB(KEYTYPE, keytype) \
258 static const struct keytype_desc_st mstype##2##keytype##_desc = { \
259 EVP_PKEY_##KEYTYPE, #KEYTYPE, \
260 ossl_##keytype##_keymgmt_functions, \
261 keytype##_decode_private_key, \
262 keytype##_decode_public_key, \
263 keytype##_adjust, \
264 keytype##_free \
265 }; \
266 static OSSL_FUNC_decoder_newctx_fn msblob2##keytype##_newctx; \
267 static void *msblob2##keytype##_newctx(void *provctx) \
268 { \
269 return msblob2key_newctx(provctx, &mstype##2##keytype##_desc); \
270 } \
271 const OSSL_DISPATCH \
272 ossl_msblob_to_##keytype##_decoder_functions[] = { \
273 { OSSL_FUNC_DECODER_NEWCTX, \
274 (void (*)(void))msblob2##keytype##_newctx }, \
275 { OSSL_FUNC_DECODER_FREECTX, \
276 (void (*)(void))msblob2key_freectx }, \
277 { OSSL_FUNC_DECODER_DOES_SELECTION, \
278 (void (*)(void))msblob2key_does_selection }, \
279 { OSSL_FUNC_DECODER_DECODE, \
280 (void (*)(void))msblob2key_decode }, \
281 { OSSL_FUNC_DECODER_EXPORT_OBJECT, \
282 (void (*)(void))msblob2key_export_object }, \
283 OSSL_DISPATCH_END \
284 }
285
286 #ifndef OPENSSL_NO_DSA
287 IMPLEMENT_MSBLOB(DSA, dsa);
288 #endif
289 IMPLEMENT_MSBLOB(RSA, rsa);
290
