pineapple-src/externals/libressl/ssl/ssl_sigalgs.c
2022-04-24 22:29:35 +02:00

355 lines
8.3 KiB
C
Executable file

/* $OpenBSD: ssl_sigalgs.c,v 1.41 2022/02/05 14:54:10 jsing Exp $ */
/*
* Copyright (c) 2018-2020 Bob Beck <beck@openbsd.org>
* Copyright (c) 2021 Joel Sing <jsing@openbsd.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <string.h>
#include <stdlib.h>
#include <openssl/evp.h>
#include <openssl/opensslconf.h>
#include "bytestring.h"
#include "ssl_locl.h"
#include "ssl_sigalgs.h"
#include "tls13_internal.h"
const struct ssl_sigalg sigalgs[] = {
{
.value = SIGALG_RSA_PKCS1_SHA512,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha512,
},
{
.value = SIGALG_ECDSA_SECP521R1_SHA512,
.key_type = EVP_PKEY_EC,
.md = EVP_sha512,
.curve_nid = NID_secp521r1,
},
#ifndef OPENSSL_NO_GOST
{
.value = SIGALG_GOSTR12_512_STREEBOG_512,
.key_type = EVP_PKEY_GOSTR12_512,
.md = EVP_streebog512,
},
#endif
{
.value = SIGALG_RSA_PKCS1_SHA384,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha384,
},
{
.value = SIGALG_ECDSA_SECP384R1_SHA384,
.key_type = EVP_PKEY_EC,
.md = EVP_sha384,
.curve_nid = NID_secp384r1,
},
{
.value = SIGALG_RSA_PKCS1_SHA256,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha256,
},
{
.value = SIGALG_ECDSA_SECP256R1_SHA256,
.key_type = EVP_PKEY_EC,
.md = EVP_sha256,
.curve_nid = NID_X9_62_prime256v1,
},
#ifndef OPENSSL_NO_GOST
{
.value = SIGALG_GOSTR12_256_STREEBOG_256,
.key_type = EVP_PKEY_GOSTR12_256,
.md = EVP_streebog256,
},
{
.value = SIGALG_GOSTR01_GOST94,
.key_type = EVP_PKEY_GOSTR01,
.md = EVP_gostr341194,
},
#endif
{
.value = SIGALG_RSA_PSS_RSAE_SHA256,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha256,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PSS_RSAE_SHA384,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha384,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PSS_RSAE_SHA512,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha512,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PSS_PSS_SHA256,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha256,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PSS_PSS_SHA384,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha384,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PSS_PSS_SHA512,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha512,
.flags = SIGALG_FLAG_RSA_PSS,
},
{
.value = SIGALG_RSA_PKCS1_SHA224,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha224,
},
{
.value = SIGALG_ECDSA_SECP224R1_SHA224,
.key_type = EVP_PKEY_EC,
.md = EVP_sha224,
},
{
.value = SIGALG_RSA_PKCS1_SHA1,
.key_type = EVP_PKEY_RSA,
.md = EVP_sha1,
},
{
.value = SIGALG_ECDSA_SHA1,
.key_type = EVP_PKEY_EC,
.md = EVP_sha1,
},
{
.value = SIGALG_RSA_PKCS1_MD5_SHA1,
.key_type = EVP_PKEY_RSA,
.md = EVP_md5_sha1,
},
{
.value = SIGALG_NONE,
},
};
/* Sigalgs for TLSv1.3, in preference order. */
const uint16_t tls13_sigalgs[] = {
SIGALG_RSA_PSS_RSAE_SHA512,
SIGALG_RSA_PKCS1_SHA512,
SIGALG_ECDSA_SECP521R1_SHA512,
SIGALG_RSA_PSS_RSAE_SHA384,
SIGALG_RSA_PKCS1_SHA384,
SIGALG_ECDSA_SECP384R1_SHA384,
SIGALG_RSA_PSS_RSAE_SHA256,
SIGALG_RSA_PKCS1_SHA256,
SIGALG_ECDSA_SECP256R1_SHA256,
};
const size_t tls13_sigalgs_len = (sizeof(tls13_sigalgs) / sizeof(tls13_sigalgs[0]));
/* Sigalgs for TLSv1.2, in preference order. */
const uint16_t tls12_sigalgs[] = {
SIGALG_RSA_PSS_RSAE_SHA512,
SIGALG_RSA_PKCS1_SHA512,
SIGALG_ECDSA_SECP521R1_SHA512,
SIGALG_RSA_PSS_RSAE_SHA384,
SIGALG_RSA_PKCS1_SHA384,
SIGALG_ECDSA_SECP384R1_SHA384,
SIGALG_RSA_PSS_RSAE_SHA256,
SIGALG_RSA_PKCS1_SHA256,
SIGALG_ECDSA_SECP256R1_SHA256,
SIGALG_RSA_PKCS1_SHA1, /* XXX */
SIGALG_ECDSA_SHA1, /* XXX */
};
const size_t tls12_sigalgs_len = (sizeof(tls12_sigalgs) / sizeof(tls12_sigalgs[0]));
static void
ssl_sigalgs_for_version(uint16_t tls_version, const uint16_t **out_values,
size_t *out_len)
{
if (tls_version >= TLS1_3_VERSION) {
*out_values = tls13_sigalgs;
*out_len = tls13_sigalgs_len;
} else {
*out_values = tls12_sigalgs;
*out_len = tls12_sigalgs_len;
}
}
static const struct ssl_sigalg *
ssl_sigalg_lookup(uint16_t value)
{
int i;
for (i = 0; sigalgs[i].value != SIGALG_NONE; i++) {
if (sigalgs[i].value == value)
return &sigalgs[i];
}
return NULL;
}
static const struct ssl_sigalg *
ssl_sigalg_from_value(SSL *s, uint16_t value)
{
const uint16_t *values;
size_t len;
int i;
ssl_sigalgs_for_version(s->s3->hs.negotiated_tls_version,
&values, &len);
for (i = 0; i < len; i++) {
if (values[i] == value)
return ssl_sigalg_lookup(value);
}
return NULL;
}
int
ssl_sigalgs_build(uint16_t tls_version, CBB *cbb)
{
const uint16_t *values;
size_t len;
size_t i;
ssl_sigalgs_for_version(tls_version, &values, &len);
/* Add values in order as long as they are supported. */
for (i = 0; i < len; i++) {
/* Do not allow the legacy value for < 1.2 to be used. */
if (values[i] == SIGALG_RSA_PKCS1_MD5_SHA1)
return 0;
if (ssl_sigalg_lookup(values[i]) == NULL)
return 0;
if (!CBB_add_u16(cbb, values[i]))
return 0;
}
return 1;
}
static const struct ssl_sigalg *
ssl_sigalg_for_legacy(SSL *s, EVP_PKEY *pkey)
{
/* Default signature algorithms used for TLSv1.2 and earlier. */
switch (EVP_PKEY_id(pkey)) {
case EVP_PKEY_RSA:
if (s->s3->hs.negotiated_tls_version < TLS1_2_VERSION)
return ssl_sigalg_lookup(SIGALG_RSA_PKCS1_MD5_SHA1);
return ssl_sigalg_lookup(SIGALG_RSA_PKCS1_SHA1);
case EVP_PKEY_EC:
return ssl_sigalg_lookup(SIGALG_ECDSA_SHA1);
#ifndef OPENSSL_NO_GOST
case EVP_PKEY_GOSTR01:
return ssl_sigalg_lookup(SIGALG_GOSTR01_GOST94);
#endif
}
SSLerror(s, SSL_R_UNKNOWN_PKEY_TYPE);
return NULL;
}
static int
ssl_sigalg_pkey_ok(SSL *s, const struct ssl_sigalg *sigalg, EVP_PKEY *pkey)
{
if (sigalg == NULL || pkey == NULL)
return 0;
if (sigalg->key_type != EVP_PKEY_id(pkey))
return 0;
/* RSA PSS must have a sufficiently large RSA key. */
if ((sigalg->flags & SIGALG_FLAG_RSA_PSS)) {
if (EVP_PKEY_id(pkey) != EVP_PKEY_RSA ||
EVP_PKEY_size(pkey) < (2 * EVP_MD_size(sigalg->md()) + 2))
return 0;
}
if (s->s3->hs.negotiated_tls_version < TLS1_3_VERSION)
return 1;
/* RSA cannot be used without PSS in TLSv1.3. */
if (sigalg->key_type == EVP_PKEY_RSA &&
(sigalg->flags & SIGALG_FLAG_RSA_PSS) == 0)
return 0;
/* Ensure that curve matches for EC keys. */
if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
if (sigalg->curve_nid == 0)
return 0;
if (EC_GROUP_get_curve_name(EC_KEY_get0_group(
EVP_PKEY_get0_EC_KEY(pkey))) != sigalg->curve_nid)
return 0;
}
return 1;
}
const struct ssl_sigalg *
ssl_sigalg_select(SSL *s, EVP_PKEY *pkey)
{
CBS cbs;
if (!SSL_USE_SIGALGS(s))
return ssl_sigalg_for_legacy(s, pkey);
/*
* RFC 5246 allows a TLS 1.2 client to send no sigalgs extension,
* in which case the server must use the default.
*/
if (s->s3->hs.negotiated_tls_version < TLS1_3_VERSION &&
s->s3->hs.sigalgs == NULL)
return ssl_sigalg_for_legacy(s, pkey);
/*
* If we get here, we have client or server sent sigalgs, use one.
*/
CBS_init(&cbs, s->s3->hs.sigalgs, s->s3->hs.sigalgs_len);
while (CBS_len(&cbs) > 0) {
const struct ssl_sigalg *sigalg;
uint16_t sigalg_value;
if (!CBS_get_u16(&cbs, &sigalg_value))
return NULL;
if ((sigalg = ssl_sigalg_from_value(s, sigalg_value)) == NULL)
continue;
if (ssl_sigalg_pkey_ok(s, sigalg, pkey))
return sigalg;
}
SSLerror(s, SSL_R_UNKNOWN_PKEY_TYPE);
return NULL;
}
const struct ssl_sigalg *
ssl_sigalg_for_peer(SSL *s, EVP_PKEY *pkey, uint16_t sigalg_value)
{
const struct ssl_sigalg *sigalg;
if (!SSL_USE_SIGALGS(s))
return ssl_sigalg_for_legacy(s, pkey);
if ((sigalg = ssl_sigalg_from_value(s, sigalg_value)) == NULL) {
SSLerror(s, SSL_R_UNKNOWN_DIGEST);
return NULL;
}
if (!ssl_sigalg_pkey_ok(s, sigalg, pkey)) {
SSLerror(s, SSL_R_WRONG_SIGNATURE_TYPE);
return NULL;
}
return sigalg;
}