1/*
2 * Copyright 2006-2022 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/* We need to use some engine deprecated APIs */
11#define OPENSSL_SUPPRESS_DEPRECATED
12
13#include "e_os.h"
14#include "eng_local.h"
15#include <openssl/evp.h>
16#include "crypto/asn1.h"
17
18/*
19 * If this symbol is defined then ENGINE_get_pkey_asn1_meth_engine(), the
20 * function that is used by EVP to hook in pkey_asn1_meth code and cache
21 * defaults (etc), will display brief debugging summaries to stderr with the
22 * 'nid'.
23 */
24/* #define ENGINE_PKEY_ASN1_METH_DEBUG */
25
26static ENGINE_TABLE *pkey_asn1_meth_table = NULL;
27
28void ENGINE_unregister_pkey_asn1_meths(ENGINE *e)
29{
30    engine_table_unregister(&pkey_asn1_meth_table, e);
31}
32
33static void engine_unregister_all_pkey_asn1_meths(void)
34{
35    engine_table_cleanup(&pkey_asn1_meth_table);
36}
37
38int ENGINE_register_pkey_asn1_meths(ENGINE *e)
39{
40    if (e->pkey_asn1_meths) {
41        const int *nids;
42        int num_nids = e->pkey_asn1_meths(e, NULL, &nids, 0);
43        if (num_nids > 0)
44            return engine_table_register(&pkey_asn1_meth_table,
45                                         engine_unregister_all_pkey_asn1_meths,
46                                         e, nids, num_nids, 0);
47    }
48    return 1;
49}
50
51void ENGINE_register_all_pkey_asn1_meths(void)
52{
53    ENGINE *e;
54
55    for (e = ENGINE_get_first(); e; e = ENGINE_get_next(e))
56        ENGINE_register_pkey_asn1_meths(e);
57}
58
59int ENGINE_set_default_pkey_asn1_meths(ENGINE *e)
60{
61    if (e->pkey_asn1_meths) {
62        const int *nids;
63        int num_nids = e->pkey_asn1_meths(e, NULL, &nids, 0);
64        if (num_nids > 0)
65            return engine_table_register(&pkey_asn1_meth_table,
66                                         engine_unregister_all_pkey_asn1_meths,
67                                         e, nids, num_nids, 1);
68    }
69    return 1;
70}
71
72/*
73 * Exposed API function to get a functional reference from the implementation
74 * table (ie. try to get a functional reference from the tabled structural
75 * references) for a given pkey_asn1_meth 'nid'
76 */
77ENGINE *ENGINE_get_pkey_asn1_meth_engine(int nid)
78{
79    return ossl_engine_table_select(&pkey_asn1_meth_table, nid,
80                                    OPENSSL_FILE, OPENSSL_LINE);
81}
82
83/*
84 * Obtains a pkey_asn1_meth implementation from an ENGINE functional
85 * reference
86 */
87const EVP_PKEY_ASN1_METHOD *ENGINE_get_pkey_asn1_meth(ENGINE *e, int nid)
88{
89    EVP_PKEY_ASN1_METHOD *ret;
90    ENGINE_PKEY_ASN1_METHS_PTR fn = ENGINE_get_pkey_asn1_meths(e);
91    if (!fn || !fn(e, &ret, NULL, nid)) {
92        ERR_raise(ERR_LIB_ENGINE, ENGINE_R_UNIMPLEMENTED_PUBLIC_KEY_METHOD);
93        return NULL;
94    }
95    return ret;
96}
97
98/* Gets the pkey_asn1_meth callback from an ENGINE structure */
99ENGINE_PKEY_ASN1_METHS_PTR ENGINE_get_pkey_asn1_meths(const ENGINE *e)
100{
101    return e->pkey_asn1_meths;
102}
103
104/* Sets the pkey_asn1_meth callback in an ENGINE structure */
105int ENGINE_set_pkey_asn1_meths(ENGINE *e, ENGINE_PKEY_ASN1_METHS_PTR f)
106{
107    e->pkey_asn1_meths = f;
108    return 1;
109}
110
111/*
112 * Internal function to free up EVP_PKEY_ASN1_METHOD structures before an
113 * ENGINE is destroyed
114 */
115
116void engine_pkey_asn1_meths_free(ENGINE *e)
117{
118    int i;
119    EVP_PKEY_ASN1_METHOD *pkm;
120    if (e->pkey_asn1_meths) {
121        const int *pknids;
122        int npknids;
123        npknids = e->pkey_asn1_meths(e, NULL, &pknids, 0);
124        for (i = 0; i < npknids; i++) {
125            if (e->pkey_asn1_meths(e, &pkm, NULL, pknids[i])) {
126                EVP_PKEY_asn1_free(pkm);
127            }
128        }
129    }
130}
131
132/*
133 * Find a method based on a string. This does a linear search through all
134 * implemented algorithms. This is OK in practice because only a small number
135 * of algorithms are likely to be implemented in an engine and it is not used
136 * for speed critical operations.
137 */
138
139const EVP_PKEY_ASN1_METHOD *ENGINE_get_pkey_asn1_meth_str(ENGINE *e,
140                                                          const char *str,
141                                                          int len)
142{
143    int i, nidcount;
144    const int *nids;
145    EVP_PKEY_ASN1_METHOD *ameth;
146    if (!e->pkey_asn1_meths)
147        return NULL;
148    if (len == -1)
149        len = strlen(str);
150    nidcount = e->pkey_asn1_meths(e, NULL, &nids, 0);
151    for (i = 0; i < nidcount; i++) {
152        e->pkey_asn1_meths(e, &ameth, NULL, nids[i]);
153        if (ameth != NULL
154            && ((int)strlen(ameth->pem_str) == len)
155            && OPENSSL_strncasecmp(ameth->pem_str, str, len) == 0)
156            return ameth;
157    }
158    return NULL;
159}
160
161typedef struct {
162    ENGINE *e;
163    const EVP_PKEY_ASN1_METHOD *ameth;
164    const char *str;
165    int len;
166} ENGINE_FIND_STR;
167
168static void look_str_cb(int nid, STACK_OF(ENGINE) *sk, ENGINE *def, void *arg)
169{
170    ENGINE_FIND_STR *lk = arg;
171    int i;
172    if (lk->ameth)
173        return;
174    for (i = 0; i < sk_ENGINE_num(sk); i++) {
175        ENGINE *e = sk_ENGINE_value(sk, i);
176        EVP_PKEY_ASN1_METHOD *ameth;
177        e->pkey_asn1_meths(e, &ameth, NULL, nid);
178        if (ameth != NULL
179                && ((int)strlen(ameth->pem_str) == lk->len)
180                && OPENSSL_strncasecmp(ameth->pem_str, lk->str, lk->len) == 0) {
181            lk->e = e;
182            lk->ameth = ameth;
183            return;
184        }
185    }
186}
187
188const EVP_PKEY_ASN1_METHOD *ENGINE_pkey_asn1_find_str(ENGINE **pe,
189                                                      const char *str,
190                                                      int len)
191{
192    ENGINE_FIND_STR fstr;
193    fstr.e = NULL;
194    fstr.ameth = NULL;
195    fstr.str = str;
196    fstr.len = len;
197
198    if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
199        ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE);
200        return NULL;
201    }
202
203    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
204        return NULL;
205    engine_table_doall(pkey_asn1_meth_table, look_str_cb, &fstr);
206    /* If found obtain a structural reference to engine */
207    if (fstr.e) {
208        fstr.e->struct_ref++;
209        ENGINE_REF_PRINT(fstr.e, 0, 1);
210    }
211    *pe = fstr.e;
212    CRYPTO_THREAD_unlock(global_engine_lock);
213    return fstr.ameth;
214}
215