1 /*
2 * Copyright 2020-2021 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 /*
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_decode(void * vctx,OSSL_CORE_BIO * cin,int selection,OSSL_CALLBACK * data_cb,void * data_cbarg,OSSL_PASSPHRASE_CALLBACK * pw_cb,void * pw_cbarg)82 static int msblob2key_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
83 OSSL_CALLBACK *data_cb, void *data_cbarg,
84 OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
85 {
86 struct msblob2key_ctx_st *ctx = vctx;
87 BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
88 const unsigned char *p;
89 unsigned char hdr_buf[16], *buf = NULL;
90 unsigned int bitlen, magic, length;
91 int isdss = -1;
92 int ispub = -1;
93 void *key = NULL;
94 int ok = 0;
95
96 if (BIO_read(in, hdr_buf, 16) != 16) {
97 ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
98 goto next;
99 }
100 ERR_set_mark();
101 p = hdr_buf;
102 ok = ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) > 0;
103 ERR_pop_to_mark();
104 if (!ok)
105 goto next;
106
107 ctx->selection = selection;
108 ok = 0; /* Assume that we fail */
109
110 if ((isdss && ctx->desc->type != EVP_PKEY_DSA)
111 || (!isdss && ctx->desc->type != EVP_PKEY_RSA))
112 goto next;
113
114 length = ossl_blob_length(bitlen, isdss, ispub);
115 if (length > BLOB_MAX_LENGTH) {
116 ERR_raise(ERR_LIB_PEM, PEM_R_HEADER_TOO_LONG);
117 goto next;
118 }
119 buf = OPENSSL_malloc(length);
120 if (buf == NULL) {
121 ERR_raise(ERR_LIB_PEM, ERR_R_MALLOC_FAILURE);
122 goto end;
123 }
124 p = buf;
125 if (BIO_read(in, buf, length) != (int)length) {
126 ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
127 goto next;
128 }
129
130 if ((selection == 0
131 || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
132 && !ispub
133 && ctx->desc->read_private_key != NULL) {
134 struct ossl_passphrase_data_st pwdata;
135
136 memset(&pwdata, 0, sizeof(pwdata));
137 if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
138 goto end;
139 p = buf;
140 key = ctx->desc->read_private_key(&p, bitlen, ispub);
141 if (selection != 0 && key == NULL)
142 goto next;
143 }
144 if (key == NULL && (selection == 0
145 || (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
146 && ispub
147 && ctx->desc->read_public_key != NULL) {
148 p = buf;
149 key = ctx->desc->read_public_key(&p, bitlen, ispub);
150 if (selection != 0 && key == NULL)
151 goto next;
152 }
153
154 if (key != NULL && ctx->desc->adjust_key != NULL)
155 ctx->desc->adjust_key(key, ctx);
156
157 next:
158 /*
159 * Indicated that we successfully decoded something, or not at all.
160 * Ending up "empty handed" is not an error.
161 */
162 ok = 1;
163
164 /*
165 * We free resources here so it's not held up during the callback, because
166 * we know the process is recursive and the allocated chunks of memory
167 * add up.
168 */
169 OPENSSL_free(buf);
170 BIO_free(in);
171 buf = NULL;
172 in = NULL;
173
174 if (key != NULL) {
175 OSSL_PARAM params[4];
176 int object_type = OSSL_OBJECT_PKEY;
177
178 params[0] =
179 OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
180 params[1] =
181 OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
182 (char *)ctx->desc->name, 0);
183 /* The address of the key becomes the octet string */
184 params[2] =
185 OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
186 &key, sizeof(key));
187 params[3] = OSSL_PARAM_construct_end();
188
189 ok = data_cb(params, data_cbarg);
190 }
191
192 end:
193 BIO_free(in);
194 OPENSSL_free(buf);
195 ctx->desc->free_key(key);
196
197 return ok;
198 }
199
200 static int
msblob2key_export_object(void * vctx,const void * reference,size_t reference_sz,OSSL_CALLBACK * export_cb,void * export_cbarg)201 msblob2key_export_object(void *vctx,
202 const void *reference, size_t reference_sz,
203 OSSL_CALLBACK *export_cb, void *export_cbarg)
204 {
205 struct msblob2key_ctx_st *ctx = vctx;
206 OSSL_FUNC_keymgmt_export_fn *export =
207 ossl_prov_get_keymgmt_export(ctx->desc->fns);
208 void *keydata;
209
210 if (reference_sz == sizeof(keydata) && export != NULL) {
211 /* The contents of the reference is the address to our object */
212 keydata = *(void **)reference;
213
214 return export(keydata, ctx->selection, export_cb, export_cbarg);
215 }
216 return 0;
217 }
218
219 /* ---------------------------------------------------------------------- */
220
221 #define dsa_decode_private_key (b2i_of_void_fn *)ossl_b2i_DSA_after_header
222 #define dsa_decode_public_key (b2i_of_void_fn *)ossl_b2i_DSA_after_header
223 #define dsa_adjust NULL
224 #define dsa_free (void (*)(void *))DSA_free
225
226 /* ---------------------------------------------------------------------- */
227
228 #define rsa_decode_private_key (b2i_of_void_fn *)ossl_b2i_RSA_after_header
229 #define rsa_decode_public_key (b2i_of_void_fn *)ossl_b2i_RSA_after_header
230
rsa_adjust(void * key,struct msblob2key_ctx_st * ctx)231 static void rsa_adjust(void *key, struct msblob2key_ctx_st *ctx)
232 {
233 ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
234 }
235
236 #define rsa_free (void (*)(void *))RSA_free
237
238 /* ---------------------------------------------------------------------- */
239
240 #define IMPLEMENT_MSBLOB(KEYTYPE, keytype) \
241 static const struct keytype_desc_st mstype##2##keytype##_desc = { \
242 EVP_PKEY_##KEYTYPE, #KEYTYPE, \
243 ossl_##keytype##_keymgmt_functions, \
244 keytype##_decode_private_key, \
245 keytype##_decode_public_key, \
246 keytype##_adjust, \
247 keytype##_free \
248 }; \
249 static OSSL_FUNC_decoder_newctx_fn msblob2##keytype##_newctx; \
250 static void *msblob2##keytype##_newctx(void *provctx) \
251 { \
252 return msblob2key_newctx(provctx, &mstype##2##keytype##_desc); \
253 } \
254 const OSSL_DISPATCH \
255 ossl_msblob_to_##keytype##_decoder_functions[] = { \
256 { OSSL_FUNC_DECODER_NEWCTX, \
257 (void (*)(void))msblob2##keytype##_newctx }, \
258 { OSSL_FUNC_DECODER_FREECTX, \
259 (void (*)(void))msblob2key_freectx }, \
260 { OSSL_FUNC_DECODER_DECODE, \
261 (void (*)(void))msblob2key_decode }, \
262 { OSSL_FUNC_DECODER_EXPORT_OBJECT, \
263 (void (*)(void))msblob2key_export_object }, \
264 { 0, NULL } \
265 }
266
267 #ifndef OPENSSL_NO_DSA
268 IMPLEMENT_MSBLOB(DSA, dsa);
269 #endif
270 IMPLEMENT_MSBLOB(RSA, rsa);
271