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/err.h>
24#include <openssl/pem.h>         /* For public PVK functions */
25#include <openssl/x509.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
33struct pvk2key_ctx_st;            /* Forward declaration */
34typedef int check_key_fn(void *, struct pvk2key_ctx_st *ctx);
35typedef void adjust_key_fn(void *, struct pvk2key_ctx_st *ctx);
36typedef void *b2i_PVK_of_bio_pw_fn(BIO *in, pem_password_cb *cb, void *u,
37                                   OSSL_LIB_CTX *libctx, const char *propq);
38typedef void free_key_fn(void *);
39struct keytype_desc_st {
40    int type;                 /* EVP key type */
41    const char *name;         /* Keytype */
42    const OSSL_DISPATCH *fns; /* Keymgmt (to pilfer functions from) */
43
44    b2i_PVK_of_bio_pw_fn *read_private_key;
45    adjust_key_fn *adjust_key;
46    free_key_fn *free_key;
47};
48
49static OSSL_FUNC_decoder_freectx_fn pvk2key_freectx;
50static OSSL_FUNC_decoder_decode_fn pvk2key_decode;
51static OSSL_FUNC_decoder_export_object_fn pvk2key_export_object;
52
53/*
54 * Context used for DER to key decoding.
55 */
56struct pvk2key_ctx_st {
57    PROV_CTX *provctx;
58    const struct keytype_desc_st *desc;
59    /* The selection that is passed to der2key_decode() */
60    int selection;
61};
62
63static struct pvk2key_ctx_st *
64pvk2key_newctx(void *provctx, const struct keytype_desc_st *desc)
65{
66    struct pvk2key_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
75static void pvk2key_freectx(void *vctx)
76{
77    struct pvk2key_ctx_st *ctx = vctx;
78
79    OPENSSL_free(ctx);
80}
81
82static int pvk2key_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 pvk2key_ctx_st *ctx = vctx;
87    BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
88    void *key = NULL;
89    int ok = 0;
90
91    if (in == NULL)
92        return 0;
93
94    ctx->selection = selection;
95
96    if ((selection == 0
97         || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
98        && ctx->desc->read_private_key != NULL) {
99        struct ossl_passphrase_data_st pwdata;
100        int err, lib, reason;
101
102        memset(&pwdata, 0, sizeof(pwdata));
103        if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
104            goto end;
105
106        key = ctx->desc->read_private_key(in, ossl_pw_pvk_password, &pwdata,
107                                          PROV_LIBCTX_OF(ctx->provctx), NULL);
108
109        /*
110         * Because the PVK API doesn't have a separate decrypt call, we need
111         * to check the error queue for certain well known errors that are
112         * considered fatal and which we pass through, while the rest gets
113         * thrown away.
114         */
115        err = ERR_peek_last_error();
116        lib = ERR_GET_LIB(err);
117        reason = ERR_GET_REASON(err);
118        if (lib == ERR_LIB_PEM
119            && (reason == PEM_R_BAD_PASSWORD_READ
120                || reason == PEM_R_BAD_DECRYPT)) {
121            ERR_clear_last_mark();
122            goto end;
123        }
124
125        if (selection != 0 && key == NULL)
126            goto next;
127    }
128
129    if (key != NULL && ctx->desc->adjust_key != NULL)
130        ctx->desc->adjust_key(key, ctx);
131
132 next:
133    /*
134     * Indicated that we successfully decoded something, or not at all.
135     * Ending up "empty handed" is not an error.
136     */
137    ok = 1;
138
139    /*
140     * We free resources here so it's not held up during the callback, because
141     * we know the process is recursive and the allocated chunks of memory
142     * add up.
143     */
144    BIO_free(in);
145    in = NULL;
146
147    if (key != NULL) {
148        OSSL_PARAM params[4];
149        int object_type = OSSL_OBJECT_PKEY;
150
151        params[0] =
152            OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
153        params[1] =
154            OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
155                                             (char *)ctx->desc->name, 0);
156        /* The address of the key becomes the octet string */
157        params[2] =
158            OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
159                                              &key, sizeof(key));
160        params[3] = OSSL_PARAM_construct_end();
161
162        ok = data_cb(params, data_cbarg);
163    }
164
165 end:
166    BIO_free(in);
167    ctx->desc->free_key(key);
168
169    return ok;
170}
171
172static int pvk2key_export_object(void *vctx,
173                                const void *reference, size_t reference_sz,
174                                OSSL_CALLBACK *export_cb, void *export_cbarg)
175{
176    struct pvk2key_ctx_st *ctx = vctx;
177    OSSL_FUNC_keymgmt_export_fn *export =
178        ossl_prov_get_keymgmt_export(ctx->desc->fns);
179    void *keydata;
180
181    if (reference_sz == sizeof(keydata) && export != NULL) {
182        /* The contents of the reference is the address to our object */
183        keydata = *(void **)reference;
184
185        return export(keydata, ctx->selection, export_cb, export_cbarg);
186    }
187    return 0;
188}
189
190/* ---------------------------------------------------------------------- */
191
192#define dsa_private_key_bio     (b2i_PVK_of_bio_pw_fn *)b2i_DSA_PVK_bio_ex
193#define dsa_adjust              NULL
194#define dsa_free                (void (*)(void *))DSA_free
195
196/* ---------------------------------------------------------------------- */
197
198#define rsa_private_key_bio     (b2i_PVK_of_bio_pw_fn *)b2i_RSA_PVK_bio_ex
199
200static void rsa_adjust(void *key, struct pvk2key_ctx_st *ctx)
201{
202    ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
203}
204
205#define rsa_free                (void (*)(void *))RSA_free
206
207/* ---------------------------------------------------------------------- */
208
209#define IMPLEMENT_MS(KEYTYPE, keytype)                                  \
210    static const struct keytype_desc_st                                 \
211    pvk2##keytype##_desc = {                                            \
212        EVP_PKEY_##KEYTYPE, #KEYTYPE,                                   \
213        ossl_##keytype##_keymgmt_functions,                             \
214        keytype##_private_key_bio,                                      \
215        keytype##_adjust,                                               \
216        keytype##_free                                                  \
217    };                                                                  \
218    static OSSL_FUNC_decoder_newctx_fn pvk2##keytype##_newctx;          \
219    static void *pvk2##keytype##_newctx(void *provctx)                  \
220    {                                                                   \
221        return pvk2key_newctx(provctx, &pvk2##keytype##_desc);          \
222    }                                                                   \
223    const OSSL_DISPATCH                                                 \
224    ossl_##pvk_to_##keytype##_decoder_functions[] = {                   \
225        { OSSL_FUNC_DECODER_NEWCTX,                                     \
226          (void (*)(void))pvk2##keytype##_newctx },                     \
227        { OSSL_FUNC_DECODER_FREECTX,                                    \
228          (void (*)(void))pvk2key_freectx },                            \
229        { OSSL_FUNC_DECODER_DECODE,                                     \
230          (void (*)(void))pvk2key_decode },                             \
231        { OSSL_FUNC_DECODER_EXPORT_OBJECT,                              \
232          (void (*)(void))pvk2key_export_object },                      \
233        { 0, NULL }                                                     \
234    }
235
236#ifndef OPENSSL_NO_DSA
237IMPLEMENT_MS(DSA, dsa);
238#endif
239IMPLEMENT_MS(RSA, rsa);
240