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#include <openssl/crypto.h>
11#include "crypto/store.h"
12#include "internal/core.h"
13#include "internal/namemap.h"
14#include "internal/property.h"
15#include "internal/provider.h"
16#include "store_local.h"
17
18int OSSL_STORE_LOADER_up_ref(OSSL_STORE_LOADER *loader)
19{
20    int ref = 0;
21
22    if (loader->prov != NULL)
23        CRYPTO_UP_REF(&loader->refcnt, &ref, loader->lock);
24    return 1;
25}
26
27void OSSL_STORE_LOADER_free(OSSL_STORE_LOADER *loader)
28{
29    if (loader != NULL && loader->prov != NULL) {
30        int i;
31
32        CRYPTO_DOWN_REF(&loader->refcnt, &i, loader->lock);
33        if (i > 0)
34            return;
35        ossl_provider_free(loader->prov);
36        CRYPTO_THREAD_lock_free(loader->lock);
37    }
38    OPENSSL_free(loader);
39}
40
41/*
42 * OSSL_STORE_LOADER_new() expects the scheme as a constant string,
43 * which we currently don't have, so we need an alternative allocator.
44 */
45static OSSL_STORE_LOADER *new_loader(OSSL_PROVIDER *prov)
46{
47    OSSL_STORE_LOADER *loader;
48
49    if ((loader = OPENSSL_zalloc(sizeof(*loader))) == NULL
50        || (loader->lock = CRYPTO_THREAD_lock_new()) == NULL) {
51        OPENSSL_free(loader);
52        return NULL;
53    }
54    loader->prov = prov;
55    ossl_provider_up_ref(prov);
56    loader->refcnt = 1;
57
58    return loader;
59}
60
61static int up_ref_loader(void *method)
62{
63    return OSSL_STORE_LOADER_up_ref(method);
64}
65
66static void free_loader(void *method)
67{
68    OSSL_STORE_LOADER_free(method);
69}
70
71/* Permanent loader method store, constructor and destructor */
72static void loader_store_free(void *vstore)
73{
74    ossl_method_store_free(vstore);
75}
76
77static void *loader_store_new(OSSL_LIB_CTX *ctx)
78{
79    return ossl_method_store_new(ctx);
80}
81
82
83static const OSSL_LIB_CTX_METHOD loader_store_method = {
84    /* We want loader_store to be cleaned up before the provider store */
85    OSSL_LIB_CTX_METHOD_PRIORITY_2,
86    loader_store_new,
87    loader_store_free,
88};
89
90/* Data to be passed through ossl_method_construct() */
91struct loader_data_st {
92    OSSL_LIB_CTX *libctx;
93    int scheme_id;               /* For get_loader_from_store() */
94    const char *scheme;          /* For get_loader_from_store() */
95    const char *propquery;       /* For get_loader_from_store() */
96
97    OSSL_METHOD_STORE *tmp_store; /* For get_tmp_loader_store() */
98
99    unsigned int flag_construct_error_occurred : 1;
100};
101
102/*
103 * Generic routines to fetch / create OSSL_STORE methods with
104 * ossl_method_construct()
105 */
106
107/* Temporary loader method store, constructor and destructor */
108static void *get_tmp_loader_store(void *data)
109{
110    struct loader_data_st *methdata = data;
111
112    if (methdata->tmp_store == NULL)
113        methdata->tmp_store = ossl_method_store_new(methdata->libctx);
114    return methdata->tmp_store;
115}
116
117 static void dealloc_tmp_loader_store(void *store)
118{
119    if (store != NULL)
120        ossl_method_store_free(store);
121}
122
123/* Get the permanent loader store */
124static OSSL_METHOD_STORE *get_loader_store(OSSL_LIB_CTX *libctx)
125{
126    return ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_STORE_LOADER_STORE_INDEX,
127                                &loader_store_method);
128}
129
130static int reserve_loader_store(void *store, void *data)
131{
132    struct loader_data_st *methdata = data;
133
134    if (store == NULL
135        && (store = get_loader_store(methdata->libctx)) == NULL)
136        return 0;
137
138    return ossl_method_lock_store(store);
139}
140
141static int unreserve_loader_store(void *store, void *data)
142{
143    struct loader_data_st *methdata = data;
144
145    if (store == NULL
146        && (store = get_loader_store(methdata->libctx)) == NULL)
147        return 0;
148
149    return ossl_method_unlock_store(store);
150}
151
152/* Get loader methods from a store, or put one in */
153static void *get_loader_from_store(void *store, const OSSL_PROVIDER **prov,
154                                   void *data)
155{
156    struct loader_data_st *methdata = data;
157    void *method = NULL;
158    int id;
159
160    if ((id = methdata->scheme_id) == 0) {
161        OSSL_NAMEMAP *namemap = ossl_namemap_stored(methdata->libctx);
162
163        id = ossl_namemap_name2num(namemap, methdata->scheme);
164    }
165
166    if (store == NULL
167        && (store = get_loader_store(methdata->libctx)) == NULL)
168        return NULL;
169
170    if (!ossl_method_store_fetch(store, id, methdata->propquery, prov, &method))
171        return NULL;
172    return method;
173}
174
175static int put_loader_in_store(void *store, void *method,
176                               const OSSL_PROVIDER *prov,
177                               const char *scheme, const char *propdef,
178                               void *data)
179{
180    struct loader_data_st *methdata = data;
181    OSSL_NAMEMAP *namemap;
182    int id;
183
184    if ((namemap = ossl_namemap_stored(methdata->libctx)) == NULL
185        || (id = ossl_namemap_name2num(namemap, scheme)) == 0)
186        return 0;
187
188    if (store == NULL && (store = get_loader_store(methdata->libctx)) == NULL)
189        return 0;
190
191    return ossl_method_store_add(store, prov, id, propdef, method,
192                                 up_ref_loader, free_loader);
193}
194
195static void *loader_from_algorithm(int scheme_id, const OSSL_ALGORITHM *algodef,
196                                   OSSL_PROVIDER *prov)
197{
198    OSSL_STORE_LOADER *loader = NULL;
199    const OSSL_DISPATCH *fns = algodef->implementation;
200
201    if ((loader = new_loader(prov)) == NULL)
202        return NULL;
203    loader->scheme_id = scheme_id;
204    loader->propdef = algodef->property_definition;
205    loader->description = algodef->algorithm_description;
206
207    for (; fns->function_id != 0; fns++) {
208        switch (fns->function_id) {
209        case OSSL_FUNC_STORE_OPEN:
210            if (loader->p_open == NULL)
211                loader->p_open = OSSL_FUNC_store_open(fns);
212            break;
213        case OSSL_FUNC_STORE_ATTACH:
214            if (loader->p_attach == NULL)
215                loader->p_attach = OSSL_FUNC_store_attach(fns);
216            break;
217        case OSSL_FUNC_STORE_SETTABLE_CTX_PARAMS:
218            if (loader->p_settable_ctx_params == NULL)
219                loader->p_settable_ctx_params =
220                    OSSL_FUNC_store_settable_ctx_params(fns);
221            break;
222        case OSSL_FUNC_STORE_SET_CTX_PARAMS:
223            if (loader->p_set_ctx_params == NULL)
224                loader->p_set_ctx_params = OSSL_FUNC_store_set_ctx_params(fns);
225            break;
226        case OSSL_FUNC_STORE_LOAD:
227            if (loader->p_load == NULL)
228                loader->p_load = OSSL_FUNC_store_load(fns);
229            break;
230        case OSSL_FUNC_STORE_EOF:
231            if (loader->p_eof == NULL)
232                loader->p_eof = OSSL_FUNC_store_eof(fns);
233            break;
234        case OSSL_FUNC_STORE_CLOSE:
235            if (loader->p_close == NULL)
236                loader->p_close = OSSL_FUNC_store_close(fns);
237            break;
238        case OSSL_FUNC_STORE_EXPORT_OBJECT:
239            if (loader->p_export_object == NULL)
240                loader->p_export_object = OSSL_FUNC_store_export_object(fns);
241            break;
242        }
243    }
244
245    if ((loader->p_open == NULL && loader->p_attach == NULL)
246        || loader->p_load == NULL
247        || loader->p_eof == NULL
248        || loader->p_close == NULL) {
249        /* Only set_ctx_params is optionaal */
250        OSSL_STORE_LOADER_free(loader);
251        ERR_raise(ERR_LIB_OSSL_STORE, OSSL_STORE_R_LOADER_INCOMPLETE);
252        return NULL;
253    }
254    return loader;
255}
256
257/*
258 * The core fetching functionality passes the scheme of the implementation.
259 * This function is responsible to getting an identity number for them,
260 * then call loader_from_algorithm() with that identity number.
261 */
262static void *construct_loader(const OSSL_ALGORITHM *algodef,
263                              OSSL_PROVIDER *prov, void *data)
264{
265    /*
266     * This function is only called if get_loader_from_store() returned
267     * NULL, so it's safe to say that of all the spots to create a new
268     * namemap entry, this is it.  Should the scheme already exist there, we
269     * know that ossl_namemap_add() will return its corresponding number.
270     */
271    struct loader_data_st *methdata = data;
272    OSSL_LIB_CTX *libctx = ossl_provider_libctx(prov);
273    OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
274    const char *scheme = algodef->algorithm_names;
275    int id = ossl_namemap_add_name(namemap, 0, scheme);
276    void *method = NULL;
277
278    if (id != 0)
279        method = loader_from_algorithm(id, algodef, prov);
280
281    /*
282     * Flag to indicate that there was actual construction errors.  This
283     * helps inner_loader_fetch() determine what error it should
284     * record on inaccessible algorithms.
285     */
286    if (method == NULL)
287        methdata->flag_construct_error_occurred = 1;
288
289    return method;
290}
291
292/* Intermediary function to avoid ugly casts, used below */
293static void destruct_loader(void *method, void *data)
294{
295    OSSL_STORE_LOADER_free(method);
296}
297
298/* Fetching support.  Can fetch by numeric identity or by scheme */
299static OSSL_STORE_LOADER *
300inner_loader_fetch(struct loader_data_st *methdata, int id,
301                   const char *scheme, const char *properties)
302{
303    OSSL_METHOD_STORE *store = get_loader_store(methdata->libctx);
304    OSSL_NAMEMAP *namemap = ossl_namemap_stored(methdata->libctx);
305    const char *const propq = properties != NULL ? properties : "";
306    void *method = NULL;
307    int unsupported = 0;
308
309    if (store == NULL || namemap == NULL) {
310        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_PASSED_INVALID_ARGUMENT);
311        return NULL;
312    }
313
314    /*
315     * If we have been passed both an id and a scheme, we have an
316     * internal programming error.
317     */
318    if (!ossl_assert(id == 0 || scheme == NULL)) {
319        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_INTERNAL_ERROR);
320        return NULL;
321    }
322
323    /* If we haven't received a name id yet, try to get one for the name */
324    if (id == 0 && scheme != NULL)
325        id = ossl_namemap_name2num(namemap, scheme);
326
327    /*
328     * If we haven't found the name yet, chances are that the algorithm to
329     * be fetched is unsupported.
330     */
331    if (id == 0)
332        unsupported = 1;
333
334    if (id == 0
335        || !ossl_method_store_cache_get(store, NULL, id, propq, &method)) {
336        OSSL_METHOD_CONSTRUCT_METHOD mcm = {
337            get_tmp_loader_store,
338            reserve_loader_store,
339            unreserve_loader_store,
340            get_loader_from_store,
341            put_loader_in_store,
342            construct_loader,
343            destruct_loader
344        };
345        OSSL_PROVIDER *prov = NULL;
346
347        methdata->scheme_id = id;
348        methdata->scheme = scheme;
349        methdata->propquery = propq;
350        methdata->flag_construct_error_occurred = 0;
351        if ((method = ossl_method_construct(methdata->libctx, OSSL_OP_STORE,
352                                            &prov, 0 /* !force_cache */,
353                                            &mcm, methdata)) != NULL) {
354            /*
355             * If construction did create a method for us, we know that there
356             * is a correct scheme_id, since those have already been calculated
357             * in get_loader_from_store() and put_loader_in_store() above.
358             */
359            if (id == 0)
360                id = ossl_namemap_name2num(namemap, scheme);
361            ossl_method_store_cache_set(store, prov, id, propq, method,
362                                        up_ref_loader, free_loader);
363        }
364
365        /*
366         * If we never were in the constructor, the algorithm to be fetched
367         * is unsupported.
368         */
369        unsupported = !methdata->flag_construct_error_occurred;
370    }
371
372    if ((id != 0 || scheme != NULL) && method == NULL) {
373        int code = unsupported ? ERR_R_UNSUPPORTED : ERR_R_FETCH_FAILED;
374        const char *helpful_msg =
375            unsupported
376            ? ( "No store loader found. For standard store loaders you need "
377                "at least one of the default or base providers available. "
378                "Did you forget to load them? Info: " )
379            : "";
380
381        if (scheme == NULL)
382            scheme = ossl_namemap_num2name(namemap, id, 0);
383        ERR_raise_data(ERR_LIB_OSSL_STORE, code,
384                       "%s%s, Scheme (%s : %d), Properties (%s)",
385                       helpful_msg,
386                       ossl_lib_ctx_get_descriptor(methdata->libctx),
387                       scheme == NULL ? "<null>" : scheme, id,
388                       properties == NULL ? "<null>" : properties);
389    }
390
391    return method;
392}
393
394OSSL_STORE_LOADER *OSSL_STORE_LOADER_fetch(OSSL_LIB_CTX *libctx,
395                                           const char *scheme,
396                                           const char *properties)
397{
398    struct loader_data_st methdata;
399    void *method;
400
401    methdata.libctx = libctx;
402    methdata.tmp_store = NULL;
403    method = inner_loader_fetch(&methdata, 0, scheme, properties);
404    dealloc_tmp_loader_store(methdata.tmp_store);
405    return method;
406}
407
408OSSL_STORE_LOADER *ossl_store_loader_fetch_by_number(OSSL_LIB_CTX *libctx,
409                                                     int scheme_id,
410                                                     const char *properties)
411{
412    struct loader_data_st methdata;
413    void *method;
414
415    methdata.libctx = libctx;
416    methdata.tmp_store = NULL;
417    method = inner_loader_fetch(&methdata, scheme_id, NULL, properties);
418    dealloc_tmp_loader_store(methdata.tmp_store);
419    return method;
420}
421
422int ossl_store_loader_store_cache_flush(OSSL_LIB_CTX *libctx)
423{
424    OSSL_METHOD_STORE *store = get_loader_store(libctx);
425
426    if (store != NULL)
427        return ossl_method_store_cache_flush_all(store);
428    return 1;
429}
430
431int ossl_store_loader_store_remove_all_provided(const OSSL_PROVIDER *prov)
432{
433    OSSL_LIB_CTX *libctx = ossl_provider_libctx(prov);
434    OSSL_METHOD_STORE *store = get_loader_store(libctx);
435
436    if (store != NULL)
437        return ossl_method_store_remove_all_provided(store, prov);
438    return 1;
439}
440
441/*
442 * Library of basic method functions
443 */
444
445const OSSL_PROVIDER *OSSL_STORE_LOADER_get0_provider(const OSSL_STORE_LOADER *loader)
446{
447    if (!ossl_assert(loader != NULL)) {
448        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_PASSED_NULL_PARAMETER);
449        return 0;
450    }
451
452    return loader->prov;
453}
454
455const char *OSSL_STORE_LOADER_get0_properties(const OSSL_STORE_LOADER *loader)
456{
457    if (!ossl_assert(loader != NULL)) {
458        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_PASSED_NULL_PARAMETER);
459        return 0;
460    }
461
462    return loader->propdef;
463}
464
465int ossl_store_loader_get_number(const OSSL_STORE_LOADER *loader)
466{
467    if (!ossl_assert(loader != NULL)) {
468        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_PASSED_NULL_PARAMETER);
469        return 0;
470    }
471
472    return loader->scheme_id;
473}
474
475const char *OSSL_STORE_LOADER_get0_description(const OSSL_STORE_LOADER *loader)
476{
477    return loader->description;
478}
479
480int OSSL_STORE_LOADER_is_a(const OSSL_STORE_LOADER *loader, const char *name)
481{
482    if (loader->prov != NULL) {
483        OSSL_LIB_CTX *libctx = ossl_provider_libctx(loader->prov);
484        OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
485
486        return ossl_namemap_name2num(namemap, name) == loader->scheme_id;
487    }
488    return 0;
489}
490
491struct do_one_data_st {
492    void (*user_fn)(OSSL_STORE_LOADER *loader, void *arg);
493    void *user_arg;
494};
495
496static void do_one(ossl_unused int id, void *method, void *arg)
497{
498    struct do_one_data_st *data = arg;
499
500    data->user_fn(method, data->user_arg);
501}
502
503void OSSL_STORE_LOADER_do_all_provided(OSSL_LIB_CTX *libctx,
504                                       void (*user_fn)(OSSL_STORE_LOADER *loader,
505                                                       void *arg),
506                                       void *user_arg)
507{
508    struct loader_data_st methdata;
509    struct do_one_data_st data;
510
511    methdata.libctx = libctx;
512    methdata.tmp_store = NULL;
513    (void)inner_loader_fetch(&methdata, 0, NULL, NULL /* properties */);
514
515    data.user_fn = user_fn;
516    data.user_arg = user_arg;
517    if (methdata.tmp_store != NULL)
518        ossl_method_store_do_all(methdata.tmp_store, &do_one, &data);
519    ossl_method_store_do_all(get_loader_store(libctx), &do_one, &data);
520    dealloc_tmp_loader_store(methdata.tmp_store);
521}
522
523int OSSL_STORE_LOADER_names_do_all(const OSSL_STORE_LOADER *loader,
524                                   void (*fn)(const char *name, void *data),
525                                   void *data)
526{
527    if (loader == NULL)
528        return 0;
529
530    if (loader->prov != NULL) {
531        OSSL_LIB_CTX *libctx = ossl_provider_libctx(loader->prov);
532        OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
533
534        return ossl_namemap_doall_names(namemap, loader->scheme_id, fn, data);
535    }
536
537    return 1;
538}
539