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#include <stdio.h>
11#include <stdlib.h>
12#include <openssl/core.h>
13#include <openssl/core_names.h>
14#include "internal/cryptlib.h"
15#include "internal/core.h"
16#include <openssl/objects.h>
17#include <openssl/evp.h>
18#include "crypto/bn.h"
19#ifndef FIPS_MODULE
20# include "crypto/asn1.h"
21#endif
22#include "crypto/evp.h"
23#include "evp_local.h"
24
25static int gen_init(EVP_PKEY_CTX *ctx, int operation)
26{
27    int ret = 0;
28
29    if (ctx == NULL)
30        goto not_supported;
31
32    evp_pkey_ctx_free_old_ops(ctx);
33    ctx->operation = operation;
34
35    if (ctx->keymgmt == NULL || ctx->keymgmt->gen_init == NULL)
36        goto legacy;
37
38    switch (operation) {
39    case EVP_PKEY_OP_PARAMGEN:
40        ctx->op.keymgmt.genctx =
41            evp_keymgmt_gen_init(ctx->keymgmt,
42                                 OSSL_KEYMGMT_SELECT_ALL_PARAMETERS, NULL);
43        break;
44    case EVP_PKEY_OP_KEYGEN:
45        ctx->op.keymgmt.genctx =
46            evp_keymgmt_gen_init(ctx->keymgmt, OSSL_KEYMGMT_SELECT_KEYPAIR,
47                                 NULL);
48        break;
49    }
50
51    if (ctx->op.keymgmt.genctx == NULL)
52        ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
53    else
54        ret = 1;
55    goto end;
56
57 legacy:
58#ifdef FIPS_MODULE
59    goto not_supported;
60#else
61    if (ctx->pmeth == NULL
62        || (operation == EVP_PKEY_OP_PARAMGEN
63            && ctx->pmeth->paramgen == NULL)
64        || (operation == EVP_PKEY_OP_KEYGEN
65            && ctx->pmeth->keygen == NULL))
66        goto not_supported;
67
68    ret = 1;
69    switch (operation) {
70    case EVP_PKEY_OP_PARAMGEN:
71        if (ctx->pmeth->paramgen_init != NULL)
72            ret = ctx->pmeth->paramgen_init(ctx);
73        break;
74    case EVP_PKEY_OP_KEYGEN:
75        if (ctx->pmeth->keygen_init != NULL)
76            ret = ctx->pmeth->keygen_init(ctx);
77        break;
78    }
79#endif
80
81 end:
82    if (ret <= 0 && ctx != NULL) {
83        evp_pkey_ctx_free_old_ops(ctx);
84        ctx->operation = EVP_PKEY_OP_UNDEFINED;
85    }
86    return ret;
87
88 not_supported:
89    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
90    ret = -2;
91    goto end;
92}
93
94int EVP_PKEY_paramgen_init(EVP_PKEY_CTX *ctx)
95{
96    return gen_init(ctx, EVP_PKEY_OP_PARAMGEN);
97}
98
99int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx)
100{
101    return gen_init(ctx, EVP_PKEY_OP_KEYGEN);
102}
103
104static int ossl_callback_to_pkey_gencb(const OSSL_PARAM params[], void *arg)
105{
106    EVP_PKEY_CTX *ctx = arg;
107    const OSSL_PARAM *param = NULL;
108    int p = -1, n = -1;
109
110    if (ctx->pkey_gencb == NULL)
111        return 1;                /* No callback?  That's fine */
112
113    if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_POTENTIAL))
114        == NULL
115        || !OSSL_PARAM_get_int(param, &p))
116        return 0;
117    if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_ITERATION))
118        == NULL
119        || !OSSL_PARAM_get_int(param, &n))
120        return 0;
121
122    ctx->keygen_info[0] = p;
123    ctx->keygen_info[1] = n;
124
125    return ctx->pkey_gencb(ctx);
126}
127
128int EVP_PKEY_generate(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
129{
130    int ret = 0;
131    EVP_PKEY *allocated_pkey = NULL;
132    /* Legacy compatible keygen callback info, only used with provider impls */
133    int gentmp[2];
134
135    if (ppkey == NULL)
136        return -1;
137
138    if (ctx == NULL)
139        goto not_supported;
140
141    if ((ctx->operation & EVP_PKEY_OP_TYPE_GEN) == 0)
142        goto not_initialized;
143
144    if (*ppkey == NULL)
145        *ppkey = allocated_pkey = EVP_PKEY_new();
146
147    if (*ppkey == NULL) {
148        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
149        return -1;
150    }
151
152    if (ctx->op.keymgmt.genctx == NULL)
153        goto legacy;
154
155    /*
156     * Asssigning gentmp to ctx->keygen_info is something our legacy
157     * implementations do.  Because the provider implementations aren't
158     * allowed to reach into our EVP_PKEY_CTX, we need to provide similar
159     * space for backward compatibility.  It's ok that we attach a local
160     * variable, as it should only be useful in the calls down from here.
161     * This is cleared as soon as it isn't useful any more, i.e. directly
162     * after the evp_keymgmt_util_gen() call.
163     */
164    ctx->keygen_info = gentmp;
165    ctx->keygen_info_count = 2;
166
167    ret = 1;
168    if (ctx->pkey != NULL) {
169        EVP_KEYMGMT *tmp_keymgmt = ctx->keymgmt;
170        void *keydata =
171            evp_pkey_export_to_provider(ctx->pkey, ctx->libctx,
172                                        &tmp_keymgmt, ctx->propquery);
173
174        if (tmp_keymgmt == NULL)
175            goto not_supported;
176        /*
177         * It's ok if keydata is NULL here.  The backend is expected to deal
178         * with that as it sees fit.
179         */
180        ret = evp_keymgmt_gen_set_template(ctx->keymgmt,
181                                           ctx->op.keymgmt.genctx, keydata);
182    }
183
184    /*
185     * the returned value from evp_keymgmt_util_gen() is cached in *ppkey,
186     * so we do not need to save it, just check it.
187     */
188    ret = ret
189        && (evp_keymgmt_util_gen(*ppkey, ctx->keymgmt, ctx->op.keymgmt.genctx,
190                                 ossl_callback_to_pkey_gencb, ctx)
191            != NULL);
192
193    ctx->keygen_info = NULL;
194
195#ifndef FIPS_MODULE
196    /* In case |*ppkey| was originally a legacy key */
197    if (ret)
198        evp_pkey_free_legacy(*ppkey);
199#endif
200
201    /*
202     * Because we still have legacy keys
203     */
204    (*ppkey)->type = ctx->legacy_keytype;
205
206    goto end;
207
208 legacy:
209#ifdef FIPS_MODULE
210    goto not_supported;
211#else
212    /*
213     * If we get here then we're using legacy paramgen/keygen. In that case
214     * the pkey in ctx (if there is one) had better not be provided (because the
215     * legacy methods may not know how to handle it). However we can only get
216     * here if ctx->op.keymgmt.genctx == NULL, but that should never be the case
217     * if ctx->pkey is provided because we don't allow this when we initialise
218     * the ctx.
219     */
220    if (ctx->pkey != NULL && !ossl_assert(!evp_pkey_is_provided(ctx->pkey)))
221        goto not_accessible;
222
223    switch (ctx->operation) {
224    case EVP_PKEY_OP_PARAMGEN:
225        ret = ctx->pmeth->paramgen(ctx, *ppkey);
226        break;
227    case EVP_PKEY_OP_KEYGEN:
228        ret = ctx->pmeth->keygen(ctx, *ppkey);
229        break;
230    default:
231        goto not_supported;
232    }
233#endif
234
235 end:
236    if (ret <= 0) {
237        if (allocated_pkey != NULL)
238            *ppkey = NULL;
239        EVP_PKEY_free(allocated_pkey);
240    }
241    return ret;
242
243 not_supported:
244    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
245    ret = -2;
246    goto end;
247 not_initialized:
248    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
249    ret = -1;
250    goto end;
251#ifndef FIPS_MODULE
252 not_accessible:
253    ERR_raise(ERR_LIB_EVP, EVP_R_INACCESSIBLE_DOMAIN_PARAMETERS);
254    ret = -1;
255    goto end;
256#endif
257}
258
259int EVP_PKEY_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
260{
261    if (ctx->operation != EVP_PKEY_OP_PARAMGEN) {
262        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
263        return -1;
264    }
265    return EVP_PKEY_generate(ctx, ppkey);
266}
267
268int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
269{
270    if (ctx->operation != EVP_PKEY_OP_KEYGEN) {
271        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
272        return -1;
273    }
274    return EVP_PKEY_generate(ctx, ppkey);
275}
276
277void EVP_PKEY_CTX_set_cb(EVP_PKEY_CTX *ctx, EVP_PKEY_gen_cb *cb)
278{
279    ctx->pkey_gencb = cb;
280}
281
282EVP_PKEY_gen_cb *EVP_PKEY_CTX_get_cb(EVP_PKEY_CTX *ctx)
283{
284    return ctx->pkey_gencb;
285}
286
287/*
288 * "translation callback" to call EVP_PKEY_CTX callbacks using BN_GENCB style
289 * callbacks.
290 */
291
292static int trans_cb(int a, int b, BN_GENCB *gcb)
293{
294    EVP_PKEY_CTX *ctx = BN_GENCB_get_arg(gcb);
295    ctx->keygen_info[0] = a;
296    ctx->keygen_info[1] = b;
297    return ctx->pkey_gencb(ctx);
298}
299
300void evp_pkey_set_cb_translate(BN_GENCB *cb, EVP_PKEY_CTX *ctx)
301{
302    BN_GENCB_set(cb, trans_cb, ctx);
303}
304
305int EVP_PKEY_CTX_get_keygen_info(EVP_PKEY_CTX *ctx, int idx)
306{
307    if (idx == -1)
308        return ctx->keygen_info_count;
309    if (idx < 0 || idx > ctx->keygen_info_count)
310        return 0;
311    return ctx->keygen_info[idx];
312}
313
314#ifndef FIPS_MODULE
315
316EVP_PKEY *EVP_PKEY_new_mac_key(int type, ENGINE *e,
317                               const unsigned char *key, int keylen)
318{
319    EVP_PKEY_CTX *mac_ctx = NULL;
320    EVP_PKEY *mac_key = NULL;
321    mac_ctx = EVP_PKEY_CTX_new_id(type, e);
322    if (!mac_ctx)
323        return NULL;
324    if (EVP_PKEY_keygen_init(mac_ctx) <= 0)
325        goto merr;
326    if (EVP_PKEY_CTX_set_mac_key(mac_ctx, key, keylen) <= 0)
327        goto merr;
328    if (EVP_PKEY_keygen(mac_ctx, &mac_key) <= 0)
329        goto merr;
330 merr:
331    EVP_PKEY_CTX_free(mac_ctx);
332    return mac_key;
333}
334
335#endif /* FIPS_MODULE */
336
337/*- All methods below can also be used in FIPS_MODULE */
338
339static int fromdata_init(EVP_PKEY_CTX *ctx, int operation)
340{
341    if (ctx == NULL || ctx->keytype == NULL)
342        goto not_supported;
343
344    evp_pkey_ctx_free_old_ops(ctx);
345    if (ctx->keymgmt == NULL)
346        goto not_supported;
347
348    ctx->operation = operation;
349    return 1;
350
351 not_supported:
352    if (ctx != NULL)
353        ctx->operation = EVP_PKEY_OP_UNDEFINED;
354    ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
355    return -2;
356}
357
358int EVP_PKEY_fromdata_init(EVP_PKEY_CTX *ctx)
359{
360    return fromdata_init(ctx, EVP_PKEY_OP_FROMDATA);
361}
362
363int EVP_PKEY_fromdata(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey, int selection,
364                      OSSL_PARAM params[])
365{
366    void *keydata = NULL;
367    EVP_PKEY *allocated_pkey = NULL;
368
369    if (ctx == NULL || (ctx->operation & EVP_PKEY_OP_FROMDATA) == 0) {
370        ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
371        return -2;
372    }
373
374    if (ppkey == NULL)
375        return -1;
376
377    if (*ppkey == NULL)
378        allocated_pkey = *ppkey = EVP_PKEY_new();
379
380    if (*ppkey == NULL) {
381        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
382        return -1;
383    }
384
385    keydata = evp_keymgmt_util_fromdata(*ppkey, ctx->keymgmt, selection, params);
386    if (keydata == NULL) {
387        if (allocated_pkey != NULL) {
388            *ppkey = NULL;
389            EVP_PKEY_free(allocated_pkey);
390        }
391        return 0;
392    }
393    /* keydata is cached in *ppkey, so we need not bother with it further */
394    return 1;
395}
396
397const OSSL_PARAM *EVP_PKEY_fromdata_settable(EVP_PKEY_CTX *ctx, int selection)
398{
399    /* We call fromdata_init to get ctx->keymgmt populated */
400    if (fromdata_init(ctx, EVP_PKEY_OP_UNDEFINED) == 1)
401        return evp_keymgmt_import_types(ctx->keymgmt, selection);
402    return NULL;
403}
404
405static OSSL_CALLBACK ossl_pkey_todata_cb;
406
407static int ossl_pkey_todata_cb(const OSSL_PARAM params[], void *arg)
408{
409    OSSL_PARAM **ret = arg;
410
411    *ret = OSSL_PARAM_dup(params);
412    return 1;
413}
414
415int EVP_PKEY_todata(const EVP_PKEY *pkey, int selection, OSSL_PARAM **params)
416{
417    if (params == NULL)
418        return 0;
419    return EVP_PKEY_export(pkey, selection, ossl_pkey_todata_cb, params);
420}
421
422#ifndef FIPS_MODULE
423struct fake_import_data_st {
424    OSSL_CALLBACK *export_cb;
425    void *export_cbarg;
426};
427
428static OSSL_FUNC_keymgmt_import_fn pkey_fake_import;
429static int pkey_fake_import(void *fake_keydata, int ignored_selection,
430                            const OSSL_PARAM params[])
431{
432    struct fake_import_data_st *data = fake_keydata;
433
434    return data->export_cb(params, data->export_cbarg);
435}
436#endif
437
438int EVP_PKEY_export(const EVP_PKEY *pkey, int selection,
439                    OSSL_CALLBACK *export_cb, void *export_cbarg)
440{
441    if (pkey == NULL) {
442        ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_NULL_PARAMETER);
443        return 0;
444    }
445#ifndef FIPS_MODULE
446    if (evp_pkey_is_legacy(pkey)) {
447        struct fake_import_data_st data;
448
449        data.export_cb = export_cb;
450        data.export_cbarg = export_cbarg;
451
452        /*
453         * We don't need to care about libctx or propq here, as we're only
454         * interested in the resulting OSSL_PARAM array.
455         */
456        return pkey->ameth->export_to(pkey, &data, pkey_fake_import,
457                                      NULL, NULL);
458    }
459#endif
460    return evp_keymgmt_util_export(pkey, selection, export_cb, export_cbarg);
461}
462