xref: /freebsd/crypto/openssl/crypto/encode_decode/encoder_pkey.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*
2  * Copyright 2019-2022 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 #include <openssl/err.h>
11 #include <openssl/ui.h>
12 #include <openssl/params.h>
13 #include <openssl/encoder.h>
14 #include <openssl/core_names.h>
15 #include <openssl/provider.h>
16 #include <openssl/safestack.h>
17 #include <openssl/trace.h>
18 #include "internal/provider.h"
19 #include "internal/property.h"
20 #include "crypto/evp.h"
21 #include "encoder_local.h"
22 
23 DEFINE_STACK_OF(OSSL_ENCODER)
24 
25 int OSSL_ENCODER_CTX_set_cipher(OSSL_ENCODER_CTX *ctx,
26                                 const char *cipher_name,
27                                 const char *propquery)
28 {
29     OSSL_PARAM params[] = { OSSL_PARAM_END, OSSL_PARAM_END, OSSL_PARAM_END };
30 
31     params[0] =
32         OSSL_PARAM_construct_utf8_string(OSSL_ENCODER_PARAM_CIPHER,
33                                          (void *)cipher_name, 0);
34     params[1] =
35         OSSL_PARAM_construct_utf8_string(OSSL_ENCODER_PARAM_PROPERTIES,
36                                          (void *)propquery, 0);
37 
38     return OSSL_ENCODER_CTX_set_params(ctx, params);
39 }
40 
41 int OSSL_ENCODER_CTX_set_passphrase(OSSL_ENCODER_CTX *ctx,
42                                     const unsigned char *kstr,
43                                     size_t klen)
44 {
45     return ossl_pw_set_passphrase(&ctx->pwdata, kstr, klen);
46 }
47 
48 int OSSL_ENCODER_CTX_set_passphrase_ui(OSSL_ENCODER_CTX *ctx,
49                                        const UI_METHOD *ui_method,
50                                        void *ui_data)
51 {
52     return ossl_pw_set_ui_method(&ctx->pwdata, ui_method, ui_data);
53 }
54 
55 int OSSL_ENCODER_CTX_set_pem_password_cb(OSSL_ENCODER_CTX *ctx,
56                                          pem_password_cb *cb, void *cbarg)
57 {
58     return ossl_pw_set_pem_password_cb(&ctx->pwdata, cb, cbarg);
59 }
60 
61 int OSSL_ENCODER_CTX_set_passphrase_cb(OSSL_ENCODER_CTX *ctx,
62                                        OSSL_PASSPHRASE_CALLBACK *cb,
63                                        void *cbarg)
64 {
65     return ossl_pw_set_ossl_passphrase_cb(&ctx->pwdata, cb, cbarg);
66 }
67 
68 /*
69  * Support for OSSL_ENCODER_CTX_new_for_type:
70  * finding a suitable encoder
71  */
72 
73 struct collected_encoder_st {
74     STACK_OF(OPENSSL_CSTRING) *names;
75     const char *output_structure;
76     const char *output_type;
77 
78     const OSSL_PROVIDER *keymgmt_prov;
79     OSSL_ENCODER_CTX *ctx;
80     unsigned int flag_find_same_provider:1;
81 
82     int error_occurred;
83 };
84 
85 static void collect_encoder(OSSL_ENCODER *encoder, void *arg)
86 {
87     struct collected_encoder_st *data = arg;
88     size_t i, end_i;
89 
90     if (data->error_occurred)
91         return;
92 
93     data->error_occurred = 1;     /* Assume the worst */
94 
95     if (data->names == NULL)
96         return;
97 
98     end_i = sk_OPENSSL_CSTRING_num(data->names);
99     for (i = 0; i < end_i; i++) {
100         const char *name = sk_OPENSSL_CSTRING_value(data->names, i);
101         const OSSL_PROVIDER *prov = OSSL_ENCODER_get0_provider(encoder);
102         void *provctx = OSSL_PROVIDER_get0_provider_ctx(prov);
103 
104         /*
105          * collect_encoder() is called in two passes, one where the encoders
106          * from the same provider as the keymgmt are looked up, and one where
107          * the other encoders are looked up.  |data->flag_find_same_provider|
108          * tells us which pass we're in.
109          */
110         if ((data->keymgmt_prov == prov) != data->flag_find_same_provider)
111             continue;
112 
113         if (!OSSL_ENCODER_is_a(encoder, name)
114             || (encoder->does_selection != NULL
115                 && !encoder->does_selection(provctx, data->ctx->selection))
116             || (data->keymgmt_prov != prov
117                 && encoder->import_object == NULL))
118             continue;
119 
120         /* Only add each encoder implementation once */
121         if (OSSL_ENCODER_CTX_add_encoder(data->ctx, encoder))
122             break;
123     }
124 
125     data->error_occurred = 0;         /* All is good now */
126 }
127 
128 struct collected_names_st {
129     STACK_OF(OPENSSL_CSTRING) *names;
130     unsigned int error_occurred:1;
131 };
132 
133 static void collect_name(const char *name, void *arg)
134 {
135     struct collected_names_st *data = arg;
136 
137     if (data->error_occurred)
138         return;
139 
140     data->error_occurred = 1;         /* Assume the worst */
141 
142     if (sk_OPENSSL_CSTRING_push(data->names, name) <= 0)
143         return;
144 
145     data->error_occurred = 0;         /* All is good now */
146 }
147 
148 /*
149  * Support for OSSL_ENCODER_to_bio:
150  * writing callback for the OSSL_PARAM (the implementation doesn't have
151  * intimate knowledge of the provider side object)
152  */
153 
154 struct construct_data_st {
155     const EVP_PKEY *pk;
156     int selection;
157 
158     OSSL_ENCODER_INSTANCE *encoder_inst;
159     const void *obj;
160     void *constructed_obj;
161 };
162 
163 static int encoder_import_cb(const OSSL_PARAM params[], void *arg)
164 {
165     struct construct_data_st *construct_data = arg;
166     OSSL_ENCODER_INSTANCE *encoder_inst = construct_data->encoder_inst;
167     OSSL_ENCODER *encoder = OSSL_ENCODER_INSTANCE_get_encoder(encoder_inst);
168     void *encoderctx = OSSL_ENCODER_INSTANCE_get_encoder_ctx(encoder_inst);
169 
170     construct_data->constructed_obj =
171         encoder->import_object(encoderctx, construct_data->selection, params);
172 
173     return (construct_data->constructed_obj != NULL);
174 }
175 
176 static const void *
177 encoder_construct_pkey(OSSL_ENCODER_INSTANCE *encoder_inst, void *arg)
178 {
179     struct construct_data_st *data = arg;
180 
181     if (data->obj == NULL) {
182         OSSL_ENCODER *encoder =
183             OSSL_ENCODER_INSTANCE_get_encoder(encoder_inst);
184         const EVP_PKEY *pk = data->pk;
185         const OSSL_PROVIDER *k_prov = EVP_KEYMGMT_get0_provider(pk->keymgmt);
186         const OSSL_PROVIDER *e_prov = OSSL_ENCODER_get0_provider(encoder);
187 
188         if (k_prov != e_prov) {
189             data->encoder_inst = encoder_inst;
190 
191             if (!evp_keymgmt_export(pk->keymgmt, pk->keydata, data->selection,
192                                     &encoder_import_cb, data))
193                 return NULL;
194             data->obj = data->constructed_obj;
195         } else {
196             data->obj = pk->keydata;
197         }
198     }
199 
200     return data->obj;
201 }
202 
203 static void encoder_destruct_pkey(void *arg)
204 {
205     struct construct_data_st *data = arg;
206 
207     if (data->encoder_inst != NULL) {
208         OSSL_ENCODER *encoder =
209             OSSL_ENCODER_INSTANCE_get_encoder(data->encoder_inst);
210 
211         encoder->free_object(data->constructed_obj);
212     }
213     data->constructed_obj = NULL;
214 }
215 
216 /*
217  * OSSL_ENCODER_CTX_new_for_pkey() returns a ctx with no encoder if
218  * it couldn't find a suitable encoder.  This allows a caller to detect if
219  * a suitable encoder was found, with OSSL_ENCODER_CTX_get_num_encoder(),
220  * and to use fallback methods if the result is NULL.
221  */
222 static int ossl_encoder_ctx_setup_for_pkey(OSSL_ENCODER_CTX *ctx,
223                                            const EVP_PKEY *pkey,
224                                            int selection,
225                                            const char *propquery)
226 {
227     struct construct_data_st *data = NULL;
228     const OSSL_PROVIDER *prov = NULL;
229     OSSL_LIB_CTX *libctx = NULL;
230     int ok = 0;
231 
232     if (!ossl_assert(ctx != NULL) || !ossl_assert(pkey != NULL)) {
233         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
234         return 0;
235     }
236 
237     if (evp_pkey_is_provided(pkey)) {
238         prov = EVP_KEYMGMT_get0_provider(pkey->keymgmt);
239         libctx = ossl_provider_libctx(prov);
240     }
241 
242     if (pkey->keymgmt != NULL) {
243         struct collected_encoder_st encoder_data;
244         struct collected_names_st keymgmt_data;
245 
246         if ((data = OPENSSL_zalloc(sizeof(*data))) == NULL) {
247             ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
248             goto err;
249         }
250 
251         /*
252          * Select the first encoder implementations in two steps.
253          * First, collect the keymgmt names, then the encoders that match.
254          */
255         keymgmt_data.names = sk_OPENSSL_CSTRING_new_null();
256         if (keymgmt_data.names == NULL) {
257             ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
258             goto err;
259         }
260 
261         keymgmt_data.error_occurred = 0;
262         EVP_KEYMGMT_names_do_all(pkey->keymgmt, collect_name, &keymgmt_data);
263         if (keymgmt_data.error_occurred) {
264             sk_OPENSSL_CSTRING_free(keymgmt_data.names);
265             goto err;
266         }
267 
268         encoder_data.names = keymgmt_data.names;
269         encoder_data.output_type = ctx->output_type;
270         encoder_data.output_structure = ctx->output_structure;
271         encoder_data.error_occurred = 0;
272         encoder_data.keymgmt_prov = prov;
273         encoder_data.ctx = ctx;
274 
275         /*
276          * Place the encoders with the a different provider as the keymgmt
277          * last (the chain is processed in reverse order)
278          */
279         encoder_data.flag_find_same_provider = 0;
280         OSSL_ENCODER_do_all_provided(libctx, collect_encoder, &encoder_data);
281 
282         /*
283          * Place the encoders with the same provider as the keymgmt first
284          * (the chain is processed in reverse order)
285          */
286         encoder_data.flag_find_same_provider = 1;
287         OSSL_ENCODER_do_all_provided(libctx, collect_encoder, &encoder_data);
288 
289         sk_OPENSSL_CSTRING_free(keymgmt_data.names);
290         if (encoder_data.error_occurred) {
291             ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
292             goto err;
293         }
294     }
295 
296     if (data != NULL && OSSL_ENCODER_CTX_get_num_encoders(ctx) != 0) {
297         if (!OSSL_ENCODER_CTX_set_construct(ctx, encoder_construct_pkey)
298             || !OSSL_ENCODER_CTX_set_construct_data(ctx, data)
299             || !OSSL_ENCODER_CTX_set_cleanup(ctx, encoder_destruct_pkey))
300             goto err;
301 
302         data->pk = pkey;
303         data->selection = selection;
304 
305         data = NULL;             /* Avoid it being freed */
306     }
307 
308     ok = 1;
309  err:
310     if (data != NULL) {
311         OSSL_ENCODER_CTX_set_construct_data(ctx, NULL);
312         OPENSSL_free(data);
313     }
314     return ok;
315 }
316 
317 OSSL_ENCODER_CTX *OSSL_ENCODER_CTX_new_for_pkey(const EVP_PKEY *pkey,
318                                                 int selection,
319                                                 const char *output_type,
320                                                 const char *output_struct,
321                                                 const char *propquery)
322 {
323     OSSL_ENCODER_CTX *ctx = NULL;
324     OSSL_LIB_CTX *libctx = NULL;
325 
326     if (pkey == NULL) {
327         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
328         return NULL;
329     }
330 
331     if (!evp_pkey_is_assigned(pkey)) {
332         ERR_raise_data(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_INVALID_ARGUMENT,
333                        "The passed EVP_PKEY must be assigned a key");
334         return NULL;
335     }
336 
337     if ((ctx = OSSL_ENCODER_CTX_new()) == NULL) {
338         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
339         return NULL;
340     }
341 
342     if (evp_pkey_is_provided(pkey)) {
343         const OSSL_PROVIDER *prov = EVP_KEYMGMT_get0_provider(pkey->keymgmt);
344 
345         libctx = ossl_provider_libctx(prov);
346     }
347 
348     OSSL_TRACE_BEGIN(ENCODER) {
349         BIO_printf(trc_out,
350                    "(ctx %p) Looking for %s encoders with selection %d\n",
351                    (void *)ctx, EVP_PKEY_get0_type_name(pkey), selection);
352         BIO_printf(trc_out, "    output type: %s, output structure: %s\n",
353                    output_type, output_struct);
354     } OSSL_TRACE_END(ENCODER);
355 
356     if (OSSL_ENCODER_CTX_set_output_type(ctx, output_type)
357         && (output_struct == NULL
358             || OSSL_ENCODER_CTX_set_output_structure(ctx, output_struct))
359         && OSSL_ENCODER_CTX_set_selection(ctx, selection)
360         && ossl_encoder_ctx_setup_for_pkey(ctx, pkey, selection, propquery)
361         && OSSL_ENCODER_CTX_add_extra(ctx, libctx, propquery)) {
362         OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
363         int save_parameters = pkey->save_parameters;
364 
365         params[0] = OSSL_PARAM_construct_int(OSSL_ENCODER_PARAM_SAVE_PARAMETERS,
366                                              &save_parameters);
367         /* ignoring error as this is only auxiliary parameter */
368         (void)OSSL_ENCODER_CTX_set_params(ctx, params);
369 
370         OSSL_TRACE_BEGIN(ENCODER) {
371             BIO_printf(trc_out, "(ctx %p) Got %d encoders\n",
372                        (void *)ctx, OSSL_ENCODER_CTX_get_num_encoders(ctx));
373         } OSSL_TRACE_END(ENCODER);
374         return ctx;
375     }
376 
377     OSSL_ENCODER_CTX_free(ctx);
378     return NULL;
379 }
380