1/*
2 * Copyright 2019-2021 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#include <string.h>
11#include <openssl/trace.h>
12#include <openssl/err.h>
13#include <openssl/conf.h>
14#include <openssl/safestack.h>
15#include <openssl/provider.h>
16#include "internal/provider.h"
17#include "internal/cryptlib.h"
18#include "provider_local.h"
19
20DEFINE_STACK_OF(OSSL_PROVIDER)
21
22/* PROVIDER config module */
23
24typedef struct {
25    CRYPTO_RWLOCK *lock;
26    STACK_OF(OSSL_PROVIDER) *activated_providers;
27} PROVIDER_CONF_GLOBAL;
28
29static void *prov_conf_ossl_ctx_new(OSSL_LIB_CTX *libctx)
30{
31    PROVIDER_CONF_GLOBAL *pcgbl = OPENSSL_zalloc(sizeof(*pcgbl));
32
33    if (pcgbl == NULL)
34        return NULL;
35
36    pcgbl->lock = CRYPTO_THREAD_lock_new();
37    if (pcgbl->lock == NULL) {
38        OPENSSL_free(pcgbl);
39        return NULL;
40    }
41
42    return pcgbl;
43}
44
45static void prov_conf_ossl_ctx_free(void *vpcgbl)
46{
47    PROVIDER_CONF_GLOBAL *pcgbl = vpcgbl;
48
49    sk_OSSL_PROVIDER_pop_free(pcgbl->activated_providers,
50                              ossl_provider_free);
51
52    OSSL_TRACE(CONF, "Cleaned up providers\n");
53    CRYPTO_THREAD_lock_free(pcgbl->lock);
54    OPENSSL_free(pcgbl);
55}
56
57static const OSSL_LIB_CTX_METHOD provider_conf_ossl_ctx_method = {
58    /* Must be freed before the provider store is freed */
59    OSSL_LIB_CTX_METHOD_PRIORITY_2,
60    prov_conf_ossl_ctx_new,
61    prov_conf_ossl_ctx_free,
62};
63
64static const char *skip_dot(const char *name)
65{
66    const char *p = strchr(name, '.');
67
68    if (p != NULL)
69        return p + 1;
70    return name;
71}
72
73static int provider_conf_params(OSSL_PROVIDER *prov,
74                                OSSL_PROVIDER_INFO *provinfo,
75                                const char *name, const char *value,
76                                const CONF *cnf)
77{
78    STACK_OF(CONF_VALUE) *sect;
79    int ok = 1;
80
81    sect = NCONF_get_section(cnf, value);
82    if (sect != NULL) {
83        int i;
84        char buffer[512];
85        size_t buffer_len = 0;
86
87        OSSL_TRACE1(CONF, "Provider params: start section %s\n", value);
88
89        if (name != NULL) {
90            OPENSSL_strlcpy(buffer, name, sizeof(buffer));
91            OPENSSL_strlcat(buffer, ".", sizeof(buffer));
92            buffer_len = strlen(buffer);
93        }
94
95        for (i = 0; i < sk_CONF_VALUE_num(sect); i++) {
96            CONF_VALUE *sectconf = sk_CONF_VALUE_value(sect, i);
97
98            if (buffer_len + strlen(sectconf->name) >= sizeof(buffer))
99                return 0;
100            buffer[buffer_len] = '\0';
101            OPENSSL_strlcat(buffer, sectconf->name, sizeof(buffer));
102            if (!provider_conf_params(prov, provinfo, buffer, sectconf->value,
103                                      cnf))
104                return 0;
105        }
106
107        OSSL_TRACE1(CONF, "Provider params: finish section %s\n", value);
108    } else {
109        OSSL_TRACE2(CONF, "Provider params: %s = %s\n", name, value);
110        if (prov != NULL)
111            ok = ossl_provider_add_parameter(prov, name, value);
112        else
113            ok = ossl_provider_info_add_parameter(provinfo, name, value);
114    }
115
116    return ok;
117}
118
119static int prov_already_activated(const char *name,
120                                  STACK_OF(OSSL_PROVIDER) *activated)
121{
122    int i, max;
123
124    if (activated == NULL)
125        return 0;
126
127    max = sk_OSSL_PROVIDER_num(activated);
128    for (i = 0; i < max; i++) {
129        OSSL_PROVIDER *tstprov = sk_OSSL_PROVIDER_value(activated, i);
130
131        if (strcmp(OSSL_PROVIDER_get0_name(tstprov), name) == 0) {
132            return 1;
133        }
134    }
135
136    return 0;
137}
138
139static int provider_conf_load(OSSL_LIB_CTX *libctx, const char *name,
140                              const char *value, const CONF *cnf)
141{
142    int i;
143    STACK_OF(CONF_VALUE) *ecmds;
144    int soft = 0;
145    OSSL_PROVIDER *prov = NULL, *actual = NULL;
146    const char *path = NULL;
147    long activate = 0;
148    int ok = 0;
149
150    name = skip_dot(name);
151    OSSL_TRACE1(CONF, "Configuring provider %s\n", name);
152    /* Value is a section containing PROVIDER commands */
153    ecmds = NCONF_get_section(cnf, value);
154
155    if (!ecmds) {
156        ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR,
157                       "section=%s not found", value);
158        return 0;
159    }
160
161    /* Find the needed data first */
162    for (i = 0; i < sk_CONF_VALUE_num(ecmds); i++) {
163        CONF_VALUE *ecmd = sk_CONF_VALUE_value(ecmds, i);
164        const char *confname = skip_dot(ecmd->name);
165        const char *confvalue = ecmd->value;
166
167        OSSL_TRACE2(CONF, "Provider command: %s = %s\n",
168                    confname, confvalue);
169
170        /* First handle some special pseudo confs */
171
172        /* Override provider name to use */
173        if (strcmp(confname, "identity") == 0)
174            name = confvalue;
175        else if (strcmp(confname, "soft_load") == 0)
176            soft = 1;
177        /* Load a dynamic PROVIDER */
178        else if (strcmp(confname, "module") == 0)
179            path = confvalue;
180        else if (strcmp(confname, "activate") == 0)
181            activate = 1;
182    }
183
184    if (activate) {
185        PROVIDER_CONF_GLOBAL *pcgbl
186            = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_PROVIDER_CONF_INDEX,
187                                    &provider_conf_ossl_ctx_method);
188
189        if (pcgbl == NULL || !CRYPTO_THREAD_write_lock(pcgbl->lock)) {
190            ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR);
191            return 0;
192        }
193        if (!prov_already_activated(name, pcgbl->activated_providers)) {
194            /*
195            * There is an attempt to activate a provider, so we should disable
196            * loading of fallbacks. Otherwise a misconfiguration could mean the
197            * intended provider does not get loaded. Subsequent fetches could
198            * then fallback to the default provider - which may be the wrong
199            * thing.
200            */
201            if (!ossl_provider_disable_fallback_loading(libctx)) {
202                CRYPTO_THREAD_unlock(pcgbl->lock);
203                ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR);
204                return 0;
205            }
206            prov = ossl_provider_find(libctx, name, 1);
207            if (prov == NULL)
208                prov = ossl_provider_new(libctx, name, NULL, 1);
209            if (prov == NULL) {
210                CRYPTO_THREAD_unlock(pcgbl->lock);
211                if (soft)
212                    ERR_clear_error();
213                return 0;
214            }
215
216            if (path != NULL)
217                ossl_provider_set_module_path(prov, path);
218
219            ok = provider_conf_params(prov, NULL, NULL, value, cnf);
220
221            if (ok) {
222                if (!ossl_provider_activate(prov, 1, 0)) {
223                    ok = 0;
224                } else if (!ossl_provider_add_to_store(prov, &actual, 0)) {
225                    ossl_provider_deactivate(prov, 1);
226                    ok = 0;
227                } else if (actual != prov
228                           && !ossl_provider_activate(actual, 1, 0)) {
229                    ossl_provider_free(actual);
230                    ok = 0;
231                } else {
232                    if (pcgbl->activated_providers == NULL)
233                        pcgbl->activated_providers = sk_OSSL_PROVIDER_new_null();
234                    if (pcgbl->activated_providers == NULL
235                        || !sk_OSSL_PROVIDER_push(pcgbl->activated_providers,
236                                                  actual)) {
237                        ossl_provider_deactivate(actual, 1);
238                        ossl_provider_free(actual);
239                        ok = 0;
240                    } else {
241                        ok = 1;
242                    }
243                }
244            }
245            if (!ok)
246                ossl_provider_free(prov);
247        }
248        CRYPTO_THREAD_unlock(pcgbl->lock);
249    } else {
250        OSSL_PROVIDER_INFO entry;
251
252        memset(&entry, 0, sizeof(entry));
253        ok = 1;
254        if (name != NULL) {
255            entry.name = OPENSSL_strdup(name);
256            if (entry.name == NULL) {
257                ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
258                ok = 0;
259            }
260        }
261        if (ok && path != NULL) {
262            entry.path = OPENSSL_strdup(path);
263            if (entry.path == NULL) {
264                ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
265                ok = 0;
266            }
267        }
268        if (ok)
269            ok = provider_conf_params(NULL, &entry, NULL, value, cnf);
270        if (ok && (entry.path != NULL || entry.parameters != NULL))
271            ok = ossl_provider_info_add_to_store(libctx, &entry);
272        if (!ok || (entry.path == NULL && entry.parameters == NULL)) {
273            ossl_provider_info_clear(&entry);
274        }
275
276    }
277
278    /*
279     * Even if ok is 0, we still return success. Failure to load a provider is
280     * not fatal. We want to continue to load the rest of the config file.
281     */
282    return 1;
283}
284
285static int provider_conf_init(CONF_IMODULE *md, const CONF *cnf)
286{
287    STACK_OF(CONF_VALUE) *elist;
288    CONF_VALUE *cval;
289    int i;
290
291    OSSL_TRACE1(CONF, "Loading providers module: section %s\n",
292                CONF_imodule_get_value(md));
293
294    /* Value is a section containing PROVIDERs to configure */
295    elist = NCONF_get_section(cnf, CONF_imodule_get_value(md));
296
297    if (!elist) {
298        ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR);
299        return 0;
300    }
301
302    for (i = 0; i < sk_CONF_VALUE_num(elist); i++) {
303        cval = sk_CONF_VALUE_value(elist, i);
304        if (!provider_conf_load(NCONF_get0_libctx((CONF *)cnf),
305                    cval->name, cval->value, cnf))
306            return 0;
307    }
308
309    return 1;
310}
311
312void ossl_provider_add_conf_module(void)
313{
314    OSSL_TRACE(CONF, "Adding config module 'providers'\n");
315    CONF_module_add("providers", provider_conf_init, NULL);
316}
317