xref: /freebsd/crypto/openssl/providers/implementations/encode_decode/decode_msblob2key.c (revision 7ef62cebc2f965b0f640263e179276928885e33d)
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  * 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 *
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 
75 static void msblob2key_freectx(void *vctx)
76 {
77     struct msblob2key_ctx_st *ctx = vctx;
78 
79     OPENSSL_free(ctx);
80 }
81 
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 (in == NULL)
97         return 0;
98 
99     if (BIO_read(in, hdr_buf, 16) != 16) {
100         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
101         goto next;
102     }
103     ERR_set_mark();
104     p = hdr_buf;
105     ok = ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) > 0;
106     ERR_pop_to_mark();
107     if (!ok)
108         goto next;
109 
110     ctx->selection = selection;
111     ok = 0;                      /* Assume that we fail */
112 
113     if ((isdss && ctx->desc->type != EVP_PKEY_DSA)
114         || (!isdss && ctx->desc->type != EVP_PKEY_RSA))
115         goto next;
116 
117     length = ossl_blob_length(bitlen, isdss, ispub);
118     if (length > BLOB_MAX_LENGTH) {
119         ERR_raise(ERR_LIB_PEM, PEM_R_HEADER_TOO_LONG);
120         goto next;
121     }
122     buf = OPENSSL_malloc(length);
123     if (buf == NULL) {
124         ERR_raise(ERR_LIB_PEM, ERR_R_MALLOC_FAILURE);
125         goto end;
126     }
127     p = buf;
128     if (BIO_read(in, buf, length) != (int)length) {
129         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
130         goto next;
131     }
132 
133     if ((selection == 0
134          || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
135         && !ispub
136         && ctx->desc->read_private_key != NULL) {
137         struct ossl_passphrase_data_st pwdata;
138 
139         memset(&pwdata, 0, sizeof(pwdata));
140         if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
141             goto end;
142         p = buf;
143         key = ctx->desc->read_private_key(&p, bitlen, ispub);
144         if (selection != 0 && key == NULL)
145             goto next;
146     }
147     if (key == NULL && (selection == 0
148          || (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
149         && ispub
150         && ctx->desc->read_public_key != NULL) {
151         p = buf;
152         key = ctx->desc->read_public_key(&p, bitlen, ispub);
153         if (selection != 0 && key == NULL)
154             goto next;
155     }
156 
157     if (key != NULL && ctx->desc->adjust_key != NULL)
158         ctx->desc->adjust_key(key, ctx);
159 
160  next:
161     /*
162      * Indicated that we successfully decoded something, or not at all.
163      * Ending up "empty handed" is not an error.
164      */
165     ok = 1;
166 
167     /*
168      * We free resources here so it's not held up during the callback, because
169      * we know the process is recursive and the allocated chunks of memory
170      * add up.
171      */
172     OPENSSL_free(buf);
173     BIO_free(in);
174     buf = NULL;
175     in = NULL;
176 
177     if (key != NULL) {
178         OSSL_PARAM params[4];
179         int object_type = OSSL_OBJECT_PKEY;
180 
181         params[0] =
182             OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
183         params[1] =
184             OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
185                                              (char *)ctx->desc->name, 0);
186         /* The address of the key becomes the octet string */
187         params[2] =
188             OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
189                                               &key, sizeof(key));
190         params[3] = OSSL_PARAM_construct_end();
191 
192         ok = data_cb(params, data_cbarg);
193     }
194 
195  end:
196     BIO_free(in);
197     OPENSSL_free(buf);
198     ctx->desc->free_key(key);
199 
200     return ok;
201 }
202 
203 static int
204 msblob2key_export_object(void *vctx,
205                          const void *reference, size_t reference_sz,
206                          OSSL_CALLBACK *export_cb, void *export_cbarg)
207 {
208     struct msblob2key_ctx_st *ctx = vctx;
209     OSSL_FUNC_keymgmt_export_fn *export =
210         ossl_prov_get_keymgmt_export(ctx->desc->fns);
211     void *keydata;
212 
213     if (reference_sz == sizeof(keydata) && export != NULL) {
214         /* The contents of the reference is the address to our object */
215         keydata = *(void **)reference;
216 
217         return export(keydata, ctx->selection, export_cb, export_cbarg);
218     }
219     return 0;
220 }
221 
222 /* ---------------------------------------------------------------------- */
223 
224 #define dsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_DSA_after_header
225 #define dsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_DSA_after_header
226 #define dsa_adjust              NULL
227 #define dsa_free                (void (*)(void *))DSA_free
228 
229 /* ---------------------------------------------------------------------- */
230 
231 #define rsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_RSA_after_header
232 #define rsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_RSA_after_header
233 
234 static void rsa_adjust(void *key, struct msblob2key_ctx_st *ctx)
235 {
236     ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
237 }
238 
239 #define rsa_free                        (void (*)(void *))RSA_free
240 
241 /* ---------------------------------------------------------------------- */
242 
243 #define IMPLEMENT_MSBLOB(KEYTYPE, keytype)                              \
244     static const struct keytype_desc_st mstype##2##keytype##_desc = {   \
245         EVP_PKEY_##KEYTYPE, #KEYTYPE,                                   \
246         ossl_##keytype##_keymgmt_functions,                             \
247         keytype##_decode_private_key,                                   \
248         keytype##_decode_public_key,                                    \
249         keytype##_adjust,                                               \
250         keytype##_free                                                  \
251     };                                                                  \
252     static OSSL_FUNC_decoder_newctx_fn msblob2##keytype##_newctx;       \
253     static void *msblob2##keytype##_newctx(void *provctx)               \
254     {                                                                   \
255         return msblob2key_newctx(provctx, &mstype##2##keytype##_desc);  \
256     }                                                                   \
257     const OSSL_DISPATCH                                                 \
258     ossl_msblob_to_##keytype##_decoder_functions[] = {                  \
259         { OSSL_FUNC_DECODER_NEWCTX,                                     \
260           (void (*)(void))msblob2##keytype##_newctx },                  \
261         { OSSL_FUNC_DECODER_FREECTX,                                    \
262           (void (*)(void))msblob2key_freectx },                         \
263         { OSSL_FUNC_DECODER_DECODE,                                     \
264           (void (*)(void))msblob2key_decode },                          \
265         { OSSL_FUNC_DECODER_EXPORT_OBJECT,                              \
266           (void (*)(void))msblob2key_export_object },                   \
267         { 0, NULL }                                                     \
268     }
269 
270 #ifndef OPENSSL_NO_DSA
271 IMPLEMENT_MSBLOB(DSA, dsa);
272 #endif
273 IMPLEMENT_MSBLOB(RSA, rsa);
274