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openssl/crypto/evp/signature.c
Pauli bcd5d3a22d libcrypto: make XXX_get_number() internal 
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15564)
2021-06-02 20:45:39 +10:00

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/*
* Copyright 2006-2021 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <stdlib.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include "internal/numbers.h" /* includes SIZE_MAX */
#include "internal/cryptlib.h"
#include "internal/provider.h"
#include "internal/core.h"
#include "crypto/evp.h"
#include "evp_local.h"
static EVP_SIGNATURE *evp_signature_new(OSSL_PROVIDER *prov)
{
EVP_SIGNATURE *signature = OPENSSL_zalloc(sizeof(EVP_SIGNATURE));
if (signature == NULL) {
ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
return NULL;
}
signature->lock = CRYPTO_THREAD_lock_new();
if (signature->lock == NULL) {
ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
OPENSSL_free(signature);
return NULL;
}
signature->prov = prov;
ossl_provider_up_ref(prov);
signature->refcnt = 1;
return signature;
}
static void *evp_signature_from_algorithm(int name_id,
const OSSL_ALGORITHM *algodef,
OSSL_PROVIDER *prov)
{
const OSSL_DISPATCH *fns = algodef->implementation;
EVP_SIGNATURE *signature = NULL;
int ctxfncnt = 0, signfncnt = 0, verifyfncnt = 0, verifyrecfncnt = 0;
int digsignfncnt = 0, digverifyfncnt = 0;
int gparamfncnt = 0, sparamfncnt = 0, gmdparamfncnt = 0, smdparamfncnt = 0;
if ((signature = evp_signature_new(prov)) == NULL) {
ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
goto err;
}
signature->name_id = name_id;
if ((signature->type_name = ossl_algorithm_get1_first_name(algodef)) == NULL)
goto err;
signature->description = algodef->algorithm_description;
for (; fns->function_id != 0; fns++) {
switch (fns->function_id) {
case OSSL_FUNC_SIGNATURE_NEWCTX:
if (signature->newctx != NULL)
break;
signature->newctx = OSSL_FUNC_signature_newctx(fns);
ctxfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SIGN_INIT:
if (signature->sign_init != NULL)
break;
signature->sign_init = OSSL_FUNC_signature_sign_init(fns);
signfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SIGN:
if (signature->sign != NULL)
break;
signature->sign = OSSL_FUNC_signature_sign(fns);
signfncnt++;
break;
case OSSL_FUNC_SIGNATURE_VERIFY_INIT:
if (signature->verify_init != NULL)
break;
signature->verify_init = OSSL_FUNC_signature_verify_init(fns);
verifyfncnt++;
break;
case OSSL_FUNC_SIGNATURE_VERIFY:
if (signature->verify != NULL)
break;
signature->verify = OSSL_FUNC_signature_verify(fns);
verifyfncnt++;
break;
case OSSL_FUNC_SIGNATURE_VERIFY_RECOVER_INIT:
if (signature->verify_recover_init != NULL)
break;
signature->verify_recover_init
= OSSL_FUNC_signature_verify_recover_init(fns);
verifyrecfncnt++;
break;
case OSSL_FUNC_SIGNATURE_VERIFY_RECOVER:
if (signature->verify_recover != NULL)
break;
signature->verify_recover
= OSSL_FUNC_signature_verify_recover(fns);
verifyrecfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT:
if (signature->digest_sign_init != NULL)
break;
signature->digest_sign_init
= OSSL_FUNC_signature_digest_sign_init(fns);
break;
case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE:
if (signature->digest_sign_update != NULL)
break;
signature->digest_sign_update
= OSSL_FUNC_signature_digest_sign_update(fns);
digsignfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL:
if (signature->digest_sign_final != NULL)
break;
signature->digest_sign_final
= OSSL_FUNC_signature_digest_sign_final(fns);
digsignfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DIGEST_SIGN:
if (signature->digest_sign != NULL)
break;
signature->digest_sign
= OSSL_FUNC_signature_digest_sign(fns);
break;
case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT:
if (signature->digest_verify_init != NULL)
break;
signature->digest_verify_init
= OSSL_FUNC_signature_digest_verify_init(fns);
break;
case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE:
if (signature->digest_verify_update != NULL)
break;
signature->digest_verify_update
= OSSL_FUNC_signature_digest_verify_update(fns);
digverifyfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL:
if (signature->digest_verify_final != NULL)
break;
signature->digest_verify_final
= OSSL_FUNC_signature_digest_verify_final(fns);
digverifyfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY:
if (signature->digest_verify != NULL)
break;
signature->digest_verify
= OSSL_FUNC_signature_digest_verify(fns);
break;
case OSSL_FUNC_SIGNATURE_FREECTX:
if (signature->freectx != NULL)
break;
signature->freectx = OSSL_FUNC_signature_freectx(fns);
ctxfncnt++;
break;
case OSSL_FUNC_SIGNATURE_DUPCTX:
if (signature->dupctx != NULL)
break;
signature->dupctx = OSSL_FUNC_signature_dupctx(fns);
break;
case OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS:
if (signature->get_ctx_params != NULL)
break;
signature->get_ctx_params
= OSSL_FUNC_signature_get_ctx_params(fns);
gparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS:
if (signature->gettable_ctx_params != NULL)
break;
signature->gettable_ctx_params
= OSSL_FUNC_signature_gettable_ctx_params(fns);
gparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS:
if (signature->set_ctx_params != NULL)
break;
signature->set_ctx_params
= OSSL_FUNC_signature_set_ctx_params(fns);
sparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS:
if (signature->settable_ctx_params != NULL)
break;
signature->settable_ctx_params
= OSSL_FUNC_signature_settable_ctx_params(fns);
sparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS:
if (signature->get_ctx_md_params != NULL)
break;
signature->get_ctx_md_params
= OSSL_FUNC_signature_get_ctx_md_params(fns);
gmdparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS:
if (signature->gettable_ctx_md_params != NULL)
break;
signature->gettable_ctx_md_params
= OSSL_FUNC_signature_gettable_ctx_md_params(fns);
gmdparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS:
if (signature->set_ctx_md_params != NULL)
break;
signature->set_ctx_md_params
= OSSL_FUNC_signature_set_ctx_md_params(fns);
smdparamfncnt++;
break;
case OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS:
if (signature->settable_ctx_md_params != NULL)
break;
signature->settable_ctx_md_params
= OSSL_FUNC_signature_settable_ctx_md_params(fns);
smdparamfncnt++;
break;
}
}
if (ctxfncnt != 2
|| (signfncnt == 0
&& verifyfncnt == 0
&& verifyrecfncnt == 0
&& digsignfncnt == 0
&& digverifyfncnt == 0
&& signature->digest_sign == NULL
&& signature->digest_verify == NULL)
|| (signfncnt != 0 && signfncnt != 2)
|| (verifyfncnt != 0 && verifyfncnt != 2)
|| (verifyrecfncnt != 0 && verifyrecfncnt != 2)
|| (digsignfncnt != 0 && digsignfncnt != 2)
|| (digsignfncnt == 2 && signature->digest_sign_init == NULL)
|| (digverifyfncnt != 0 && digverifyfncnt != 2)
|| (digverifyfncnt == 2 && signature->digest_verify_init == NULL)
|| (signature->digest_sign != NULL
&& signature->digest_sign_init == NULL)
|| (signature->digest_verify != NULL
&& signature->digest_verify_init == NULL)
|| (gparamfncnt != 0 && gparamfncnt != 2)
|| (sparamfncnt != 0 && sparamfncnt != 2)
|| (gmdparamfncnt != 0 && gmdparamfncnt != 2)
|| (smdparamfncnt != 0 && smdparamfncnt != 2)) {
/*
* In order to be a consistent set of functions we must have at least
* a set of context functions (newctx and freectx) as well as a set of
* "signature" functions:
* (sign_init, sign) or
* (verify_init verify) or
* (verify_recover_init, verify_recover) or
* (digest_sign_init, digest_sign_update, digest_sign_final) or
* (digest_verify_init, digest_verify_update, digest_verify_final) or
* (digest_sign_init, digest_sign) or
* (digest_verify_init, digest_verify).
*
* set_ctx_params and settable_ctx_params are optional, but if one of
* them is present then the other one must also be present. The same
* applies to get_ctx_params and gettable_ctx_params. The same rules
* apply to the "md_params" functions. The dupctx function is optional.
*/
ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);
goto err;
}
return signature;
err:
EVP_SIGNATURE_free(signature);
return NULL;
}
void EVP_SIGNATURE_free(EVP_SIGNATURE *signature)
{
int i;
if (signature == NULL)
return;
CRYPTO_DOWN_REF(&signature->refcnt, &i, signature->lock);
if (i > 0)
return;
OPENSSL_free(signature->type_name);
ossl_provider_free(signature->prov);
CRYPTO_THREAD_lock_free(signature->lock);
OPENSSL_free(signature);
}
int EVP_SIGNATURE_up_ref(EVP_SIGNATURE *signature)
{
int ref = 0;
CRYPTO_UP_REF(&signature->refcnt, &ref, signature->lock);
return 1;
}
OSSL_PROVIDER *EVP_SIGNATURE_get0_provider(const EVP_SIGNATURE *signature)
{
return signature->prov;
}
EVP_SIGNATURE *EVP_SIGNATURE_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
const char *properties)
{
return evp_generic_fetch(ctx, OSSL_OP_SIGNATURE, algorithm, properties,
evp_signature_from_algorithm,
(int (*)(void *))EVP_SIGNATURE_up_ref,
(void (*)(void *))EVP_SIGNATURE_free);
}
int EVP_SIGNATURE_is_a(const EVP_SIGNATURE *signature, const char *name)
{
return evp_is_a(signature->prov, signature->name_id, NULL, name);
}
int evp_signature_get_number(const EVP_SIGNATURE *signature)
{
return signature->name_id;
}
const char *EVP_SIGNATURE_get0_name(const EVP_SIGNATURE *signature)
{
return signature->type_name;
}
const char *EVP_SIGNATURE_get0_description(const EVP_SIGNATURE *signature)
{
return signature->description;
}
void EVP_SIGNATURE_do_all_provided(OSSL_LIB_CTX *libctx,
void (*fn)(EVP_SIGNATURE *signature,
void *arg),
void *arg)
{
evp_generic_do_all(libctx, OSSL_OP_SIGNATURE,
(void (*)(void *, void *))fn, arg,
evp_signature_from_algorithm,
(void (*)(void *))EVP_SIGNATURE_free);
}
int EVP_SIGNATURE_names_do_all(const EVP_SIGNATURE *signature,
void (*fn)(const char *name, void *data),
void *data)
{
if (signature->prov != NULL)
return evp_names_do_all(signature->prov, signature->name_id, fn, data);
return 1;
}
const OSSL_PARAM *EVP_SIGNATURE_gettable_ctx_params(const EVP_SIGNATURE *sig)
{
void *provctx;
if (sig == NULL || sig->gettable_ctx_params == NULL)
return NULL;
provctx = ossl_provider_ctx(EVP_SIGNATURE_get0_provider(sig));
return sig->gettable_ctx_params(NULL, provctx);
}
const OSSL_PARAM *EVP_SIGNATURE_settable_ctx_params(const EVP_SIGNATURE *sig)
{
void *provctx;
if (sig == NULL || sig->settable_ctx_params == NULL)
return NULL;
provctx = ossl_provider_ctx(EVP_SIGNATURE_get0_provider(sig));
return sig->settable_ctx_params(NULL, provctx);
}
static int evp_pkey_signature_init(EVP_PKEY_CTX *ctx, int operation,
const OSSL_PARAM params[])
{
int ret = 0;
void *provkey = NULL;
EVP_SIGNATURE *signature = NULL;
EVP_KEYMGMT *tmp_keymgmt = NULL;
const char *supported_sig = NULL;
if (ctx == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
evp_pkey_ctx_free_old_ops(ctx);
ctx->operation = operation;
ERR_set_mark();
if (evp_pkey_ctx_is_legacy(ctx))
goto legacy;
/*
* Ensure that the key is provided, either natively, or as a cached export.
* If not, go legacy
*/
tmp_keymgmt = ctx->keymgmt;
provkey = evp_pkey_export_to_provider(ctx->pkey, ctx->libctx,
&tmp_keymgmt, ctx->propquery);
if (tmp_keymgmt == NULL)
goto legacy;
if (!EVP_KEYMGMT_up_ref(tmp_keymgmt)) {
ERR_clear_last_mark();
ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
goto err;
}
EVP_KEYMGMT_free(ctx->keymgmt);
ctx->keymgmt = tmp_keymgmt;
if (ctx->keymgmt->query_operation_name != NULL)
supported_sig = ctx->keymgmt->query_operation_name(OSSL_OP_SIGNATURE);
/*
* If we didn't get a supported sig, assume there is one with the
* same name as the key type.
*/
if (supported_sig == NULL)
supported_sig = ctx->keytype;
/*
* Because we cleared out old ops, we shouldn't need to worry about
* checking if signature is already there.
*/
signature =
EVP_SIGNATURE_fetch(ctx->libctx, supported_sig, ctx->propquery);
if (signature == NULL
|| (EVP_KEYMGMT_get0_provider(ctx->keymgmt)
!= EVP_SIGNATURE_get0_provider(signature))) {
/*
* We don't need to free ctx->keymgmt here, as it's not necessarily
* tied to this operation. It will be freed by EVP_PKEY_CTX_free().
*/
EVP_SIGNATURE_free(signature);
goto legacy;
}
/*
* If we don't have the full support we need with provided methods,
* let's go see if legacy does.
*/
ERR_pop_to_mark();
/* No more legacy from here down to legacy: */
ctx->op.sig.signature = signature;
ctx->op.sig.algctx =
signature->newctx(ossl_provider_ctx(signature->prov), ctx->propquery);
if (ctx->op.sig.algctx == NULL) {
/* The provider key can stay in the cache */
ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
goto err;
}
switch (operation) {
case EVP_PKEY_OP_SIGN:
if (signature->sign_init == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
ret = -2;
goto err;
}
ret = signature->sign_init(ctx->op.sig.algctx, provkey, params);
break;
case EVP_PKEY_OP_VERIFY:
if (signature->verify_init == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
ret = -2;
goto err;
}
ret = signature->verify_init(ctx->op.sig.algctx, provkey, params);
break;
case EVP_PKEY_OP_VERIFYRECOVER:
if (signature->verify_recover_init == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
ret = -2;
goto err;
}
ret = signature->verify_recover_init(ctx->op.sig.algctx, provkey,
params);
break;
default:
ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
goto err;
}
if (ret <= 0) {
signature->freectx(ctx->op.sig.algctx);
ctx->op.sig.algctx = NULL;
goto err;
}
goto end;
legacy:
/*
* If we don't have the full support we need with provided methods,
* let's go see if legacy does.
*/
ERR_pop_to_mark();
if (ctx->pmeth == NULL
|| (operation == EVP_PKEY_OP_SIGN && ctx->pmeth->sign == NULL)
|| (operation == EVP_PKEY_OP_VERIFY && ctx->pmeth->verify == NULL)
|| (operation == EVP_PKEY_OP_VERIFYRECOVER
&& ctx->pmeth->verify_recover == NULL)) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
switch (operation) {
case EVP_PKEY_OP_SIGN:
if (ctx->pmeth->sign_init == NULL)
return 1;
ret = ctx->pmeth->sign_init(ctx);
break;
case EVP_PKEY_OP_VERIFY:
if (ctx->pmeth->verify_init == NULL)
return 1;
ret = ctx->pmeth->verify_init(ctx);
break;
case EVP_PKEY_OP_VERIFYRECOVER:
if (ctx->pmeth->verify_recover_init == NULL)
return 1;
ret = ctx->pmeth->verify_recover_init(ctx);
break;
default:
ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
goto err;
}
if (ret <= 0)
goto err;
end:
#ifndef FIPS_MODULE
if (ret > 0)
ret = evp_pkey_ctx_use_cached_data(ctx);
#endif
return ret;
err:
evp_pkey_ctx_free_old_ops(ctx);
ctx->operation = EVP_PKEY_OP_UNDEFINED;
return ret;
}
int EVP_PKEY_sign_init(EVP_PKEY_CTX *ctx)
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_SIGN, NULL);
}
int EVP_PKEY_sign_init_ex(EVP_PKEY_CTX *ctx, const OSSL_PARAM params[])
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_SIGN, params);
}
int EVP_PKEY_sign(EVP_PKEY_CTX *ctx,
unsigned char *sig, size_t *siglen,
const unsigned char *tbs, size_t tbslen)
{
int ret;
if (ctx == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
if (ctx->operation != EVP_PKEY_OP_SIGN) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
return -1;
}
if (ctx->op.sig.algctx == NULL)
goto legacy;
ret = ctx->op.sig.signature->sign(ctx->op.sig.algctx, sig, siglen,
SIZE_MAX, tbs, tbslen);
return ret;
legacy:
if (ctx->pmeth == NULL || ctx->pmeth->sign == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
M_check_autoarg(ctx, sig, siglen, EVP_F_EVP_PKEY_SIGN)
return ctx->pmeth->sign(ctx, sig, siglen, tbs, tbslen);
}
int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx)
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFY, NULL);
}
int EVP_PKEY_verify_init_ex(EVP_PKEY_CTX *ctx, const OSSL_PARAM params[])
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFY, params);
}
int EVP_PKEY_verify(EVP_PKEY_CTX *ctx,
const unsigned char *sig, size_t siglen,
const unsigned char *tbs, size_t tbslen)
{
int ret;
if (ctx == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
if (ctx->operation != EVP_PKEY_OP_VERIFY) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
return -1;
}
if (ctx->op.sig.algctx == NULL)
goto legacy;
ret = ctx->op.sig.signature->verify(ctx->op.sig.algctx, sig, siglen,
tbs, tbslen);
return ret;
legacy:
if (ctx->pmeth == NULL || ctx->pmeth->verify == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
return ctx->pmeth->verify(ctx, sig, siglen, tbs, tbslen);
}
int EVP_PKEY_verify_recover_init(EVP_PKEY_CTX *ctx)
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFYRECOVER, NULL);
}
int EVP_PKEY_verify_recover_init_ex(EVP_PKEY_CTX *ctx,
const OSSL_PARAM params[])
{
return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFYRECOVER, params);
}
int EVP_PKEY_verify_recover(EVP_PKEY_CTX *ctx,
unsigned char *rout, size_t *routlen,
const unsigned char *sig, size_t siglen)
{
int ret;
if (ctx == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
if (ctx->operation != EVP_PKEY_OP_VERIFYRECOVER) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_INITIALIZED);
return -1;
}
if (ctx->op.sig.algctx == NULL)
goto legacy;
ret = ctx->op.sig.signature->verify_recover(ctx->op.sig.algctx, rout,
routlen,
(rout == NULL ? 0 : *routlen),
sig, siglen);
return ret;
legacy:
if (ctx->pmeth == NULL || ctx->pmeth->verify_recover == NULL) {
ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
}
M_check_autoarg(ctx, rout, routlen, EVP_F_EVP_PKEY_VERIFY_RECOVER)
return ctx->pmeth->verify_recover(ctx, rout, routlen, sig, siglen);
}
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