rsa.c
/*
* Copyright 2019-2020 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
*/
/*
* RSA low level APIs are deprecated for public use, but still ok for
* internal use.
*/
#include "internal/deprecated.h"
#include <string.h>
#include <openssl/crypto.h>
#include <openssl/core_dispatch.h>
#include <openssl/core_names.h>
#include <openssl/err.h>
#include <openssl/rsa.h>
#include <openssl/params.h>
#include <openssl/evp.h>
#include "internal/cryptlib.h"
#include "internal/nelem.h"
#include "internal/sizes.h"
#include "crypto/rsa.h"
#include "prov/providercommon.h"
#include "prov/providercommonerr.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/der_rsa.h"
#include "prov/securitycheck.h"
#define RSA_DEFAULT_DIGEST_NAME OSSL_DIGEST_NAME_SHA1
static OSSL_FUNC_signature_newctx_fn rsa_newctx;
static OSSL_FUNC_signature_sign_init_fn rsa_sign_init;
static OSSL_FUNC_signature_verify_init_fn rsa_verify_init;
static OSSL_FUNC_signature_verify_recover_init_fn rsa_verify_recover_init;
static OSSL_FUNC_signature_sign_fn rsa_sign;
static OSSL_FUNC_signature_verify_fn rsa_verify;
static OSSL_FUNC_signature_verify_recover_fn rsa_verify_recover;
static OSSL_FUNC_signature_digest_sign_init_fn rsa_digest_sign_init;
static OSSL_FUNC_signature_digest_sign_update_fn rsa_digest_signverify_update;
static OSSL_FUNC_signature_digest_sign_final_fn rsa_digest_sign_final;
static OSSL_FUNC_signature_digest_verify_init_fn rsa_digest_verify_init;
static OSSL_FUNC_signature_digest_verify_update_fn rsa_digest_signverify_update;
static OSSL_FUNC_signature_digest_verify_final_fn rsa_digest_verify_final;
static OSSL_FUNC_signature_freectx_fn rsa_freectx;
static OSSL_FUNC_signature_dupctx_fn rsa_dupctx;
static OSSL_FUNC_signature_get_ctx_params_fn rsa_get_ctx_params;
static OSSL_FUNC_signature_gettable_ctx_params_fn rsa_gettable_ctx_params;
static OSSL_FUNC_signature_set_ctx_params_fn rsa_set_ctx_params;
static OSSL_FUNC_signature_settable_ctx_params_fn rsa_settable_ctx_params;
static OSSL_FUNC_signature_get_ctx_md_params_fn rsa_get_ctx_md_params;
static OSSL_FUNC_signature_gettable_ctx_md_params_fn rsa_gettable_ctx_md_params;
static OSSL_FUNC_signature_set_ctx_md_params_fn rsa_set_ctx_md_params;
static OSSL_FUNC_signature_settable_ctx_md_params_fn rsa_settable_ctx_md_params;
static OSSL_ITEM padding_item[] = {
{ RSA_PKCS1_PADDING, OSSL_PKEY_RSA_PAD_MODE_PKCSV15 },
{ RSA_SSLV23_PADDING, OSSL_PKEY_RSA_PAD_MODE_SSLV23 },
{ RSA_NO_PADDING, OSSL_PKEY_RSA_PAD_MODE_NONE },
{ RSA_X931_PADDING, OSSL_PKEY_RSA_PAD_MODE_X931 },
{ RSA_PKCS1_PSS_PADDING, OSSL_PKEY_RSA_PAD_MODE_PSS },
{ 0, NULL }
};
/*
* What's passed as an actual key is defined by the KEYMGMT interface.
* We happen to know that our KEYMGMT simply passes RSA structures, so
* we use that here too.
*/
typedef struct {
OSSL_LIB_CTX *libctx;
char *propq;
RSA *rsa;
int operation;
/*
* Flag to determine if the hash function can be changed (1) or not (0)
* Because it's dangerous to change during a DigestSign or DigestVerify
* operation, this flag is cleared by their Init function, and set again
* by their Final function.
*/
unsigned int flag_allow_md : 1;
/* The Algorithm Identifier of the combined signature algorithm */
unsigned char aid_buf[128];
unsigned char *aid;
size_t aid_len;
/* main digest */
EVP_MD *md;
EVP_MD_CTX *mdctx;
int mdnid;
char mdname[OSSL_MAX_NAME_SIZE]; /* Purely informational */
/* RSA padding mode */
int pad_mode;
/* message digest for MGF1 */
EVP_MD *mgf1_md;
char mgf1_mdname[OSSL_MAX_NAME_SIZE]; /* Purely informational */
/* PSS salt length */
int saltlen;
/* Minimum salt length or -1 if no PSS parameter restriction */
int min_saltlen;
/* Temp buffer */
unsigned char *tbuf;
} PROV_RSA_CTX;
static size_t rsa_get_md_size(const PROV_RSA_CTX *prsactx)
{
if (prsactx->md != NULL)
return EVP_MD_size(prsactx->md);
return 0;
}
static int rsa_check_padding(int mdnid, int padding)
{
if (padding == RSA_NO_PADDING) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_PADDING_MODE);
return 0;
}
if (padding == RSA_X931_PADDING) {
if (RSA_X931_hash_id(mdnid) == -1) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_X931_DIGEST);
return 0;
}
}
return 1;
}
static int rsa_check_parameters(PROV_RSA_CTX *prsactx)
{
if (prsactx->pad_mode == RSA_PKCS1_PSS_PADDING) {
int max_saltlen;
/* See if minimum salt length exceeds maximum possible */
max_saltlen = RSA_size(prsactx->rsa) - EVP_MD_size(prsactx->md);
if ((RSA_bits(prsactx->rsa) & 0x7) == 1)
max_saltlen--;
if (prsactx->min_saltlen < 0 || prsactx->min_saltlen > max_saltlen) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SALT_LENGTH);
return 0;
}
}
return 1;
}
static void *rsa_newctx(void *provctx, const char *propq)
{
PROV_RSA_CTX *prsactx = NULL;
char *propq_copy = NULL;
if (!ossl_prov_is_running())
return NULL;
if ((prsactx = OPENSSL_zalloc(sizeof(PROV_RSA_CTX))) == NULL
|| (propq != NULL
&& (propq_copy = OPENSSL_strdup(propq)) == NULL)) {
OPENSSL_free(prsactx);
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
return NULL;
}
prsactx->libctx = PROV_LIBCTX_OF(provctx);
prsactx->flag_allow_md = 1;
prsactx->propq = propq_copy;
return prsactx;
}
/* True if PSS parameters are restricted */
#define rsa_pss_restricted(prsactx) (prsactx->min_saltlen != -1)
static int rsa_setup_md(PROV_RSA_CTX *ctx, const char *mdname,
const char *mdprops)
{
if (mdprops == NULL)
mdprops = ctx->propq;
if (mdname != NULL) {
WPACKET pkt;
EVP_MD *md = EVP_MD_fetch(ctx->libctx, mdname, mdprops);
int sha1_allowed = (ctx->operation != EVP_PKEY_OP_SIGN);
int md_nid = digest_rsa_sign_get_md_nid(md, sha1_allowed);
size_t mdname_len = strlen(mdname);
if (md == NULL
|| md_nid == NID_undef
|| !rsa_check_padding(md_nid, ctx->pad_mode)
|| mdname_len >= sizeof(ctx->mdname)) {
if (md == NULL)
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"%s could not be fetched", mdname);
if (md_nid == NID_undef)
ERR_raise_data(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED,
"digest=%s", mdname);
if (mdname_len >= sizeof(ctx->mdname))
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"%s exceeds name buffer length", mdname);
EVP_MD_free(md);
return 0;
}
EVP_MD_CTX_free(ctx->mdctx);
EVP_MD_free(ctx->md);
/*
* TODO(3.0) Should we care about DER writing errors?
* All it really means is that for some reason, there's no
* AlgorithmIdentifier to be had (consider RSA with MD5-SHA1),
* but the operation itself is still valid, just as long as it's
* not used to construct anything that needs an AlgorithmIdentifier.
*/
ctx->aid_len = 0;
if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
&& ossl_DER_w_algorithmIdentifier_MDWithRSAEncryption(&pkt, -1,
ctx->rsa,
md_nid)
&& WPACKET_finish(&pkt)) {
WPACKET_get_total_written(&pkt, &ctx->aid_len);
ctx->aid = WPACKET_get_curr(&pkt);
}
WPACKET_cleanup(&pkt);
ctx->mdctx = NULL;
ctx->md = md;
ctx->mdnid = md_nid;
OPENSSL_strlcpy(ctx->mdname, mdname, sizeof(ctx->mdname));
}
return 1;
}
static int rsa_setup_mgf1_md(PROV_RSA_CTX *ctx, const char *mdname,
const char *mdprops)
{
size_t len;
EVP_MD *md = NULL;
if (mdprops == NULL)
mdprops = ctx->propq;
if (ctx->mgf1_mdname[0] != '\0')
EVP_MD_free(ctx->mgf1_md);
if ((md = EVP_MD_fetch(ctx->libctx, mdname, mdprops)) == NULL) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"%s could not be fetched", mdname);
return 0;
}
/* The default for mgf1 is SHA1 - so allow SHA1 */
if (digest_rsa_sign_get_md_nid(md, 1) == NID_undef) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED,
"digest=%s", mdname);
EVP_MD_free(md);
return 0;
}
ctx->mgf1_md = md;
len = OPENSSL_strlcpy(ctx->mgf1_mdname, mdname, sizeof(ctx->mgf1_mdname));
if (len >= sizeof(ctx->mgf1_mdname)) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"%s exceeds name buffer length", mdname);
return 0;
}
return 1;
}
static int rsa_signverify_init(void *vprsactx, void *vrsa, int operation)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (!ossl_prov_is_running())
return 0;
if (prsactx == NULL || vrsa == NULL || !RSA_up_ref(vrsa))
return 0;
RSA_free(prsactx->rsa);
prsactx->rsa = vrsa;
prsactx->operation = operation;
if (!ossl_rsa_check_key(vrsa, operation == EVP_PKEY_OP_SIGN)) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
return 0;
}
/* Maximum for sign, auto for verify */
prsactx->saltlen = RSA_PSS_SALTLEN_AUTO;
prsactx->min_saltlen = -1;
switch (RSA_test_flags(prsactx->rsa, RSA_FLAG_TYPE_MASK)) {
case RSA_FLAG_TYPE_RSA:
prsactx->pad_mode = RSA_PKCS1_PADDING;
break;
case RSA_FLAG_TYPE_RSASSAPSS:
prsactx->pad_mode = RSA_PKCS1_PSS_PADDING;
{
const RSA_PSS_PARAMS_30 *pss =
ossl_rsa_get0_pss_params_30(prsactx->rsa);
if (!ossl_rsa_pss_params_30_is_unrestricted(pss)) {
int md_nid = ossl_rsa_pss_params_30_hashalg(pss);
int mgf1md_nid = ossl_rsa_pss_params_30_maskgenhashalg(pss);
int min_saltlen = ossl_rsa_pss_params_30_saltlen(pss);
const char *mdname, *mgf1mdname;
size_t len;
mdname = ossl_rsa_oaeppss_nid2name(md_nid);
mgf1mdname = ossl_rsa_oaeppss_nid2name(mgf1md_nid);
prsactx->min_saltlen = min_saltlen;
if (mdname == NULL) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"PSS restrictions lack hash algorithm");
return 0;
}
if (mgf1mdname == NULL) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"PSS restrictions lack MGF1 hash algorithm");
return 0;
}
len = OPENSSL_strlcpy(prsactx->mdname, mdname,
sizeof(prsactx->mdname));
if (len >= sizeof(prsactx->mdname)) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"hash algorithm name too long");
return 0;
}
len = OPENSSL_strlcpy(prsactx->mgf1_mdname, mgf1mdname,
sizeof(prsactx->mgf1_mdname));
if (len >= sizeof(prsactx->mgf1_mdname)) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
"MGF1 hash algorithm name too long");
return 0;
}
prsactx->saltlen = min_saltlen;
return rsa_setup_md(prsactx, mdname, prsactx->propq)
&& rsa_setup_mgf1_md(prsactx, mgf1mdname, prsactx->propq)
&& rsa_check_parameters(prsactx);
}
}
break;
default:
ERR_raise(ERR_LIB_RSA, PROV_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return 0;
}
return 1;
}
static int setup_tbuf(PROV_RSA_CTX *ctx)
{
if (ctx->tbuf != NULL)
return 1;
if ((ctx->tbuf = OPENSSL_malloc(RSA_size(ctx->rsa))) == NULL) {
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
return 0;
}
return 1;
}
static void clean_tbuf(PROV_RSA_CTX *ctx)
{
if (ctx->tbuf != NULL)
OPENSSL_cleanse(ctx->tbuf, RSA_size(ctx->rsa));
}
static void free_tbuf(PROV_RSA_CTX *ctx)
{
clean_tbuf(ctx);
OPENSSL_free(ctx->tbuf);
ctx->tbuf = NULL;
}
static int rsa_sign_init(void *vprsactx, void *vrsa)
{
if (!ossl_prov_is_running())
return 0;
return rsa_signverify_init(vprsactx, vrsa, EVP_PKEY_OP_SIGN);
}
static int rsa_sign(void *vprsactx, unsigned char *sig, size_t *siglen,
size_t sigsize, const unsigned char *tbs, size_t tbslen)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
int ret;
size_t rsasize = RSA_size(prsactx->rsa);
size_t mdsize = rsa_get_md_size(prsactx);
if (!ossl_prov_is_running())
return 0;
if (sig == NULL) {
*siglen = rsasize;
return 1;
}
if (sigsize < rsasize) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_SIGNATURE_SIZE,
"is %zu, should be at least %zu", sigsize, rsasize);
return 0;
}
if (mdsize != 0) {
if (tbslen != mdsize) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST_LENGTH);
return 0;
}
#ifndef FIPS_MODULE
if (EVP_MD_is_a(prsactx->md, OSSL_DIGEST_NAME_MDC2)) {
unsigned int sltmp;
if (prsactx->pad_mode != RSA_PKCS1_PADDING) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_PADDING_MODE,
"only PKCS#1 padding supported with MDC2");
return 0;
}
ret = RSA_sign_ASN1_OCTET_STRING(0, tbs, tbslen, sig, &sltmp,
prsactx->rsa);
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret = sltmp;
goto end;
}
#endif
switch (prsactx->pad_mode) {
case RSA_X931_PADDING:
if ((size_t)RSA_size(prsactx->rsa) < tbslen + 1) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_KEY_SIZE_TOO_SMALL,
"RSA key size = %d, expected minimum = %d",
RSA_size(prsactx->rsa), tbslen + 1);
return 0;
}
if (!setup_tbuf(prsactx)) {
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
return 0;
}
memcpy(prsactx->tbuf, tbs, tbslen);
prsactx->tbuf[tbslen] = RSA_X931_hash_id(prsactx->mdnid);
ret = RSA_private_encrypt(tbslen + 1, prsactx->tbuf,
sig, prsactx->rsa, RSA_X931_PADDING);
clean_tbuf(prsactx);
break;
case RSA_PKCS1_PADDING:
{
unsigned int sltmp;
ret = RSA_sign(prsactx->mdnid, tbs, tbslen, sig, &sltmp,
prsactx->rsa);
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret = sltmp;
}
break;
case RSA_PKCS1_PSS_PADDING:
/* Check PSS restrictions */
if (rsa_pss_restricted(prsactx)) {
switch (prsactx->saltlen) {
case RSA_PSS_SALTLEN_DIGEST:
if (prsactx->min_saltlen > EVP_MD_size(prsactx->md)) {
ERR_raise_data(ERR_LIB_PROV,
PROV_R_PSS_SALTLEN_TOO_SMALL,
"minimum salt length set to %d, "
"but the digest only gives %d",
prsactx->min_saltlen,
EVP_MD_size(prsactx->md));
return 0;
}
/* FALLTHRU */
default:
if (prsactx->saltlen >= 0
&& prsactx->saltlen < prsactx->min_saltlen) {
ERR_raise_data(ERR_LIB_PROV,
PROV_R_PSS_SALTLEN_TOO_SMALL,
"minimum salt length set to %d, but the"
"actual salt length is only set to %d",
prsactx->min_saltlen,
prsactx->saltlen);
return 0;
}
break;
}
}
if (!setup_tbuf(prsactx))
return 0;
if (!RSA_padding_add_PKCS1_PSS_mgf1(prsactx->rsa,
prsactx->tbuf, tbs,
prsactx->md, prsactx->mgf1_md,
prsactx->saltlen)) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret = RSA_private_encrypt(RSA_size(prsactx->rsa), prsactx->tbuf,
sig, prsactx->rsa, RSA_NO_PADDING);
clean_tbuf(prsactx);
break;
default:
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_PADDING_MODE,
"Only X.931, PKCS#1 v1.5 or PSS padding allowed");
return 0;
}
} else {
ret = RSA_private_encrypt(tbslen, tbs, sig, prsactx->rsa,
prsactx->pad_mode);
}
#ifndef FIPS_MODULE
end:
#endif
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
*siglen = ret;
return 1;
}
static int rsa_verify_recover_init(void *vprsactx, void *vrsa)
{
if (!ossl_prov_is_running())
return 0;
return rsa_signverify_init(vprsactx, vrsa, EVP_PKEY_OP_VERIFYRECOVER);
}
static int rsa_verify_recover(void *vprsactx,
unsigned char *rout,
size_t *routlen,
size_t routsize,
const unsigned char *sig,
size_t siglen)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
int ret;
if (!ossl_prov_is_running())
return 0;
if (rout == NULL) {
*routlen = RSA_size(prsactx->rsa);
return 1;
}
if (prsactx->md != NULL) {
switch (prsactx->pad_mode) {
case RSA_X931_PADDING:
if (!setup_tbuf(prsactx))
return 0;
ret = RSA_public_decrypt(siglen, sig, prsactx->tbuf, prsactx->rsa,
RSA_X931_PADDING);
if (ret < 1) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret--;
if (prsactx->tbuf[ret] != RSA_X931_hash_id(prsactx->mdnid)) {
ERR_raise(ERR_LIB_PROV, PROV_R_ALGORITHM_MISMATCH);
return 0;
}
if (ret != EVP_MD_size(prsactx->md)) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST_LENGTH,
"Should be %d, but got %d",
EVP_MD_size(prsactx->md), ret);
return 0;
}
*routlen = ret;
if (rout != prsactx->tbuf) {
if (routsize < (size_t)ret) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL,
"buffer size is %d, should be %d",
routsize, ret);
return 0;
}
memcpy(rout, prsactx->tbuf, ret);
}
break;
case RSA_PKCS1_PADDING:
{
size_t sltmp;
ret = int_rsa_verify(prsactx->mdnid, NULL, 0, rout, &sltmp,
sig, siglen, prsactx->rsa);
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret = sltmp;
}
break;
default:
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_PADDING_MODE,
"Only X.931 or PKCS#1 v1.5 padding allowed");
return 0;
}
} else {
ret = RSA_public_decrypt(siglen, sig, rout, prsactx->rsa,
prsactx->pad_mode);
if (ret < 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
}
*routlen = ret;
return 1;
}
static int rsa_verify_init(void *vprsactx, void *vrsa)
{
if (!ossl_prov_is_running())
return 0;
return rsa_signverify_init(vprsactx, vrsa, EVP_PKEY_OP_VERIFY);
}
static int rsa_verify(void *vprsactx, const unsigned char *sig, size_t siglen,
const unsigned char *tbs, size_t tbslen)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
size_t rslen;
if (!ossl_prov_is_running())
return 0;
if (prsactx->md != NULL) {
switch (prsactx->pad_mode) {
case RSA_PKCS1_PADDING:
if (!RSA_verify(prsactx->mdnid, tbs, tbslen, sig, siglen,
prsactx->rsa)) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
return 1;
case RSA_X931_PADDING:
if (!setup_tbuf(prsactx))
return 0;
if (rsa_verify_recover(prsactx, prsactx->tbuf, &rslen, 0,
sig, siglen) <= 0)
return 0;
break;
case RSA_PKCS1_PSS_PADDING:
{
int ret;
size_t mdsize;
/*
* We need to check this for the RSA_verify_PKCS1_PSS_mgf1()
* call
*/
mdsize = rsa_get_md_size(prsactx);
if (tbslen != mdsize) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST_LENGTH,
"Should be %d, but got %d",
mdsize, tbslen);
return 0;
}
if (!setup_tbuf(prsactx))
return 0;
ret = RSA_public_decrypt(siglen, sig, prsactx->tbuf,
prsactx->rsa, RSA_NO_PADDING);
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
ret = RSA_verify_PKCS1_PSS_mgf1(prsactx->rsa, tbs,
prsactx->md, prsactx->mgf1_md,
prsactx->tbuf,
prsactx->saltlen);
if (ret <= 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
return 1;
}
default:
ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_PADDING_MODE,
"Only X.931, PKCS#1 v1.5 or PSS padding allowed");
return 0;
}
} else {
if (!setup_tbuf(prsactx))
return 0;
rslen = RSA_public_decrypt(siglen, sig, prsactx->tbuf, prsactx->rsa,
prsactx->pad_mode);
if (rslen == 0) {
ERR_raise(ERR_LIB_PROV, ERR_LIB_RSA);
return 0;
}
}
if ((rslen != tbslen) || memcmp(tbs, prsactx->tbuf, rslen))
return 0;
return 1;
}
static int rsa_digest_signverify_init(void *vprsactx, const char *mdname,
void *vrsa, int operation)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (!ossl_prov_is_running())
return 0;
if (prsactx != NULL)
prsactx->flag_allow_md = 0;
if (!rsa_signverify_init(vprsactx, vrsa, operation)
|| !rsa_setup_md(prsactx, mdname, NULL)) /* TODO RL */
return 0;
prsactx->mdctx = EVP_MD_CTX_new();
if (prsactx->mdctx == NULL) {
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
goto error;
}
if (!EVP_DigestInit_ex(prsactx->mdctx, prsactx->md, NULL))
goto error;
return 1;
error:
EVP_MD_CTX_free(prsactx->mdctx);
EVP_MD_free(prsactx->md);
prsactx->mdctx = NULL;
prsactx->md = NULL;
return 0;
}
static int rsa_digest_signverify_update(void *vprsactx,
const unsigned char *data,
size_t datalen)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx == NULL || prsactx->mdctx == NULL)
return 0;
return EVP_DigestUpdate(prsactx->mdctx, data, datalen);
}
static int rsa_digest_sign_init(void *vprsactx, const char *mdname,
void *vrsa)
{
if (!ossl_prov_is_running())
return 0;
return rsa_digest_signverify_init(vprsactx, mdname, vrsa,
EVP_PKEY_OP_SIGN);
}
static int rsa_digest_sign_final(void *vprsactx, unsigned char *sig,
size_t *siglen, size_t sigsize)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
unsigned char digest[EVP_MAX_MD_SIZE];
unsigned int dlen = 0;
if (!ossl_prov_is_running() || prsactx == NULL)
return 0;
prsactx->flag_allow_md = 1;
if (prsactx->mdctx == NULL)
return 0;
/*
* If sig is NULL then we're just finding out the sig size. Other fields
* are ignored. Defer to rsa_sign.
*/
if (sig != NULL) {
/*
* The digests used here are all known (see rsa_get_md_nid()), so they
* should not exceed the internal buffer size of EVP_MAX_MD_SIZE.
*/
if (!EVP_DigestFinal_ex(prsactx->mdctx, digest, &dlen))
return 0;
}
return rsa_sign(vprsactx, sig, siglen, sigsize, digest, (size_t)dlen);
}
static int rsa_digest_verify_init(void *vprsactx, const char *mdname,
void *vrsa)
{
if (!ossl_prov_is_running())
return 0;
return rsa_digest_signverify_init(vprsactx, mdname, vrsa,
EVP_PKEY_OP_VERIFY);
}
int rsa_digest_verify_final(void *vprsactx, const unsigned char *sig,
size_t siglen)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
unsigned char digest[EVP_MAX_MD_SIZE];
unsigned int dlen = 0;
if (!ossl_prov_is_running())
return 0;
if (prsactx == NULL)
return 0;
prsactx->flag_allow_md = 1;
if (prsactx->mdctx == NULL)
return 0;
/*
* The digests used here are all known (see rsa_get_md_nid()), so they
* should not exceed the internal buffer size of EVP_MAX_MD_SIZE.
*/
if (!EVP_DigestFinal_ex(prsactx->mdctx, digest, &dlen))
return 0;
return rsa_verify(vprsactx, sig, siglen, digest, (size_t)dlen);
}
static void rsa_freectx(void *vprsactx)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx == NULL)
return;
EVP_MD_CTX_free(prsactx->mdctx);
EVP_MD_free(prsactx->md);
EVP_MD_free(prsactx->mgf1_md);
OPENSSL_free(prsactx->propq);
free_tbuf(prsactx);
RSA_free(prsactx->rsa);
OPENSSL_clear_free(prsactx, sizeof(*prsactx));
}
static void *rsa_dupctx(void *vprsactx)
{
PROV_RSA_CTX *srcctx = (PROV_RSA_CTX *)vprsactx;
PROV_RSA_CTX *dstctx;
if (!ossl_prov_is_running())
return NULL;
dstctx = OPENSSL_zalloc(sizeof(*srcctx));
if (dstctx == NULL) {
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
return NULL;
}
*dstctx = *srcctx;
dstctx->rsa = NULL;
dstctx->md = NULL;
dstctx->mdctx = NULL;
dstctx->tbuf = NULL;
dstctx->propq = NULL;
if (srcctx->rsa != NULL && !RSA_up_ref(srcctx->rsa))
goto err;
dstctx->rsa = srcctx->rsa;
if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
goto err;
dstctx->md = srcctx->md;
if (srcctx->mgf1_md != NULL && !EVP_MD_up_ref(srcctx->mgf1_md))
goto err;
dstctx->mgf1_md = srcctx->mgf1_md;
if (srcctx->mdctx != NULL) {
dstctx->mdctx = EVP_MD_CTX_new();
if (dstctx->mdctx == NULL
|| !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
goto err;
}
if (srcctx->propq != NULL) {
dstctx->propq = OPENSSL_strdup(srcctx->propq);
if (dstctx->propq == NULL)
goto err;
}
return dstctx;
err:
rsa_freectx(dstctx);
return NULL;
}
static int rsa_get_ctx_params(void *vprsactx, OSSL_PARAM *params)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
OSSL_PARAM *p;
if (prsactx == NULL || params == NULL)
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
if (p != NULL
&& !OSSL_PARAM_set_octet_string(p, prsactx->aid, prsactx->aid_len))
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_PAD_MODE);
if (p != NULL)
switch (p->data_type) {
case OSSL_PARAM_INTEGER:
if (!OSSL_PARAM_set_int(p, prsactx->pad_mode))
return 0;
break;
case OSSL_PARAM_UTF8_STRING:
{
int i;
const char *word = NULL;
for (i = 0; padding_item[i].id != 0; i++) {
if (prsactx->pad_mode == (int)padding_item[i].id) {
word = padding_item[i].ptr;
break;
}
}
if (word != NULL) {
if (!OSSL_PARAM_set_utf8_string(p, word))
return 0;
} else {
ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
}
}
break;
default:
return 0;
}
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
if (p != NULL && !OSSL_PARAM_set_utf8_string(p, prsactx->mdname))
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_MGF1_DIGEST);
if (p != NULL && !OSSL_PARAM_set_utf8_string(p, prsactx->mgf1_mdname))
return 0;
p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_PSS_SALTLEN);
if (p != NULL) {
if (p->data_type == OSSL_PARAM_INTEGER) {
if (!OSSL_PARAM_set_int(p, prsactx->saltlen))
return 0;
} else if (p->data_type == OSSL_PARAM_UTF8_STRING) {
const char *value = NULL;
switch (prsactx->saltlen) {
case RSA_PSS_SALTLEN_DIGEST:
value = OSSL_PKEY_RSA_PSS_SALT_LEN_DIGEST;
break;
case RSA_PSS_SALTLEN_MAX:
value = OSSL_PKEY_RSA_PSS_SALT_LEN_MAX;
break;
case RSA_PSS_SALTLEN_AUTO:
value = OSSL_PKEY_RSA_PSS_SALT_LEN_AUTO;
break;
default:
{
int len = BIO_snprintf(p->data, p->data_size, "%d",
prsactx->saltlen);
if (len <= 0)
return 0;
p->return_size = len;
break;
}
}
if (value != NULL
&& !OSSL_PARAM_set_utf8_string(p, value))
return 0;
}
}
return 1;
}
static const OSSL_PARAM known_gettable_ctx_params[] = {
OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PAD_MODE, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_MGF1_DIGEST, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PSS_SALTLEN, NULL, 0),
OSSL_PARAM_END
};
static const OSSL_PARAM *rsa_gettable_ctx_params(ossl_unused void *vctx)
{
return known_gettable_ctx_params;
}
static int rsa_set_ctx_params(void *vprsactx, const OSSL_PARAM params[])
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
const OSSL_PARAM *p;
if (prsactx == NULL || params == NULL)
return 0;
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
/* Not allowed during certain operations */
if (p != NULL && !prsactx->flag_allow_md)
return 0;
if (p != NULL) {
char mdname[OSSL_MAX_NAME_SIZE] = "", *pmdname = mdname;
char mdprops[OSSL_MAX_PROPQUERY_SIZE] = "", *pmdprops = mdprops;
const OSSL_PARAM *propsp =
OSSL_PARAM_locate_const(params,
OSSL_SIGNATURE_PARAM_PROPERTIES);
if (!OSSL_PARAM_get_utf8_string(p, &pmdname, sizeof(mdname)))
return 0;
if (propsp == NULL)
pmdprops = NULL;
else if (!OSSL_PARAM_get_utf8_string(propsp,
&pmdprops, sizeof(mdprops)))
return 0;
if (rsa_pss_restricted(prsactx)) {
/* TODO(3.0) figure out what to do for prsactx->md == NULL */
if (prsactx->md == NULL || EVP_MD_is_a(prsactx->md, mdname))
return 1;
ERR_raise(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED);
return 0;
}
/* non-PSS code follows */
if (!rsa_setup_md(prsactx, mdname, pmdprops))
return 0;
}
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_PAD_MODE);
if (p != NULL) {
int pad_mode = 0;
const char *err_extra_text = NULL;
switch (p->data_type) {
case OSSL_PARAM_INTEGER: /* Support for legacy pad mode number */
if (!OSSL_PARAM_get_int(p, &pad_mode))
return 0;
break;
case OSSL_PARAM_UTF8_STRING:
{
int i;
if (p->data == NULL)
return 0;
for (i = 0; padding_item[i].id != 0; i++) {
if (strcmp(p->data, padding_item[i].ptr) == 0) {
pad_mode = padding_item[i].id;
break;
}
}
}
break;
default:
return 0;
}
switch (pad_mode) {
case RSA_PKCS1_OAEP_PADDING:
/*
* OAEP padding is for asymmetric cipher only so is not compatible
* with signature use.
*/
err_extra_text = "OAEP padding not allowed for signing / verifying";
goto bad_pad;
case RSA_PKCS1_PSS_PADDING:
if ((prsactx->operation
& (EVP_PKEY_OP_SIGN | EVP_PKEY_OP_VERIFY)) == 0) {
err_extra_text =
"PSS padding only allowed for sign and verify operations";
goto bad_pad;
}
if (prsactx->md == NULL
&& !rsa_setup_md(prsactx, RSA_DEFAULT_DIGEST_NAME, NULL)) {
return 0;
}
break;
case RSA_PKCS1_PADDING:
err_extra_text = "PKCS#1 padding not allowed with RSA-PSS";
goto cont;
case RSA_SSLV23_PADDING:
err_extra_text = "SSLv3 padding not allowed with RSA-PSS";
goto cont;
case RSA_NO_PADDING:
err_extra_text = "No padding not allowed with RSA-PSS";
goto cont;
case RSA_X931_PADDING:
err_extra_text = "X.931 padding not allowed with RSA-PSS";
cont:
if (RSA_test_flags(prsactx->rsa,
RSA_FLAG_TYPE_MASK) == RSA_FLAG_TYPE_RSA)
break;
/* FALLTHRU */
default:
bad_pad:
if (err_extra_text == NULL)
ERR_raise(ERR_LIB_PROV,
PROV_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
else
ERR_raise_data(ERR_LIB_PROV,
PROV_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE,
err_extra_text);
return 0;
}
if (!rsa_check_padding(prsactx->mdnid, pad_mode))
return 0;
prsactx->pad_mode = pad_mode;
}
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_PSS_SALTLEN);
if (p != NULL) {
int saltlen;
if (prsactx->pad_mode != RSA_PKCS1_PSS_PADDING) {
ERR_raise_data(ERR_LIB_PROV, PROV_R_NOT_SUPPORTED,
"PSS saltlen can only be specified if "
"PSS padding has been specified first");
return 0;
}
switch (p->data_type) {
case OSSL_PARAM_INTEGER: /* Support for legacy pad mode number */
if (!OSSL_PARAM_get_int(p, &saltlen))
return 0;
break;
case OSSL_PARAM_UTF8_STRING:
if (strcmp(p->data, OSSL_PKEY_RSA_PSS_SALT_LEN_DIGEST) == 0)
saltlen = RSA_PSS_SALTLEN_DIGEST;
else if (strcmp(p->data, OSSL_PKEY_RSA_PSS_SALT_LEN_MAX) == 0)
saltlen = RSA_PSS_SALTLEN_MAX;
else if (strcmp(p->data, OSSL_PKEY_RSA_PSS_SALT_LEN_AUTO) == 0)
saltlen = RSA_PSS_SALTLEN_AUTO;
else
saltlen = atoi(p->data);
break;
default:
return 0;
}
/*
* RSA_PSS_SALTLEN_MAX seems curiously named in this check.
* Contrary to what it's name suggests, it's the currently
* lowest saltlen number possible.
*/
if (saltlen < RSA_PSS_SALTLEN_MAX) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_PSS_SALTLEN);
return 0;
}
if (rsa_pss_restricted(prsactx)) {
switch (saltlen) {
case RSA_PSS_SALTLEN_AUTO:
if (prsactx->operation == EVP_PKEY_OP_VERIFY) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_PSS_SALTLEN);
return 0;
}
break;
case RSA_PSS_SALTLEN_DIGEST:
if (prsactx->min_saltlen > EVP_MD_size(prsactx->md)) {
ERR_raise_data(ERR_LIB_PROV,
PROV_R_PSS_SALTLEN_TOO_SMALL,
"Should be more than %d, but would be "
"set to match digest size (%d)",
prsactx->min_saltlen,
EVP_MD_size(prsactx->md));
return 0;
}
break;
default:
if (saltlen >= 0 && saltlen < prsactx->min_saltlen) {
ERR_raise_data(ERR_LIB_PROV,
PROV_R_PSS_SALTLEN_TOO_SMALL,
"Should be more than %d, "
"but would be set to %d",
prsactx->min_saltlen, saltlen);
return 0;
}
}
}
prsactx->saltlen = saltlen;
}
p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_MGF1_DIGEST);
if (p != NULL) {
char mdname[OSSL_MAX_NAME_SIZE] = "", *pmdname = mdname;
char mdprops[OSSL_MAX_PROPQUERY_SIZE] = "", *pmdprops = mdprops;
const OSSL_PARAM *propsp =
OSSL_PARAM_locate_const(params,
OSSL_SIGNATURE_PARAM_MGF1_PROPERTIES);
if (!OSSL_PARAM_get_utf8_string(p, &pmdname, sizeof(mdname)))
return 0;
if (propsp == NULL)
pmdprops = NULL;
else if (!OSSL_PARAM_get_utf8_string(propsp,
&pmdprops, sizeof(mdprops)))
return 0;
if (prsactx->pad_mode != RSA_PKCS1_PSS_PADDING) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MGF1_MD);
return 0;
}
if (rsa_pss_restricted(prsactx)) {
/* TODO(3.0) figure out what to do for prsactx->mgf1_md == NULL */
if (prsactx->mgf1_md == NULL
|| EVP_MD_is_a(prsactx->mgf1_md, mdname))
return 1;
ERR_raise(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED);
return 0;
}
/* non-PSS code follows */
if (!rsa_setup_mgf1_md(prsactx, mdname, pmdprops))
return 0;
}
return 1;
}
static const OSSL_PARAM known_settable_ctx_params[] = {
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PAD_MODE, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PROPERTIES, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_MGF1_DIGEST, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_MGF1_PROPERTIES, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PSS_SALTLEN, NULL, 0),
OSSL_PARAM_END
};
static const OSSL_PARAM *rsa_settable_ctx_params(ossl_unused void *provctx)
{
/*
* TODO(3.0): Should this function return a different set of settable ctx
* params if the ctx is being used for a DigestSign/DigestVerify? In that
* case it is not allowed to set the digest size/digest name because the
* digest is explicitly set as part of the init.
*/
return known_settable_ctx_params;
}
static int rsa_get_ctx_md_params(void *vprsactx, OSSL_PARAM *params)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx->mdctx == NULL)
return 0;
return EVP_MD_CTX_get_params(prsactx->mdctx, params);
}
static const OSSL_PARAM *rsa_gettable_ctx_md_params(void *vprsactx)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx->md == NULL)
return 0;
return EVP_MD_gettable_ctx_params(prsactx->md);
}
static int rsa_set_ctx_md_params(void *vprsactx, const OSSL_PARAM params[])
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx->mdctx == NULL)
return 0;
return EVP_MD_CTX_set_params(prsactx->mdctx, params);
}
static const OSSL_PARAM *rsa_settable_ctx_md_params(void *vprsactx)
{
PROV_RSA_CTX *prsactx = (PROV_RSA_CTX *)vprsactx;
if (prsactx->md == NULL)
return 0;
return EVP_MD_settable_ctx_params(prsactx->md);
}
const OSSL_DISPATCH ossl_rsa_signature_functions[] = {
{ OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))rsa_newctx },
{ OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))rsa_sign_init },
{ OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))rsa_sign },
{ OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))rsa_verify_init },
{ OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))rsa_verify },
{ OSSL_FUNC_SIGNATURE_VERIFY_RECOVER_INIT,
(void (*)(void))rsa_verify_recover_init },
{ OSSL_FUNC_SIGNATURE_VERIFY_RECOVER,
(void (*)(void))rsa_verify_recover },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
(void (*)(void))rsa_digest_sign_init },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
(void (*)(void))rsa_digest_signverify_update },
{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
(void (*)(void))rsa_digest_sign_final },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
(void (*)(void))rsa_digest_verify_init },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
(void (*)(void))rsa_digest_signverify_update },
{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
(void (*)(void))rsa_digest_verify_final },
{ OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))rsa_freectx },
{ OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))rsa_dupctx },
{ OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))rsa_get_ctx_params },
{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
(void (*)(void))rsa_gettable_ctx_params },
{ OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))rsa_set_ctx_params },
{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
(void (*)(void))rsa_settable_ctx_params },
{ OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
(void (*)(void))rsa_get_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
(void (*)(void))rsa_gettable_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
(void (*)(void))rsa_set_ctx_md_params },
{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
(void (*)(void))rsa_settable_ctx_md_params },
{ 0, NULL }
};
