Adding upstream version 1.12.0.upstream/1.12.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 316 insertions, 0 deletions

diff --git a/src/rs256.c b/src/rs256.c
new file mode 100644
index 0000000..59ceb94
--- /dev/null
+++ b/src/rs256.c
@@ -0,0 +1,316 @@
+/*
+ * Copyright (c) 2018-2022 Yubico AB. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <openssl/bn.h>
+#include <openssl/rsa.h>
+#include <openssl/obj_mac.h>
+
+#include "fido.h"
+#include "fido/rs256.h"
+
+#if OPENSSL_VERSION_NUMBER >= 0x30000000
+#define get0_RSA(x)	EVP_PKEY_get0_RSA((x))
+#else
+#define get0_RSA(x)	EVP_PKEY_get0((x))
+#endif
+
+#if defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x3050200fL
+static EVP_MD *
+rs256_get_EVP_MD(void)
+{
+	const EVP_MD *from;
+	EVP_MD *to = NULL;
+
+	if ((from = EVP_sha256()) != NULL && (to = malloc(sizeof(*to))) != NULL)
+		memcpy(to, from, sizeof(*to));
+
+	return (to);
+}
+
+static void
+rs256_free_EVP_MD(EVP_MD *md)
+{
+	freezero(md, sizeof(*md));
+}
+#elif OPENSSL_VERSION_NUMBER >= 0x30000000
+static EVP_MD *
+rs256_get_EVP_MD(void)
+{
+	return (EVP_MD_fetch(NULL, "SHA2-256", NULL));
+}
+
+static void
+rs256_free_EVP_MD(EVP_MD *md)
+{
+	EVP_MD_free(md);
+}
+#else
+static EVP_MD *
+rs256_get_EVP_MD(void)
+{
+	const EVP_MD *md;
+
+	if ((md = EVP_sha256()) == NULL)
+		return (NULL);
+
+	return (EVP_MD_meth_dup(md));
+}
+
+static void
+rs256_free_EVP_MD(EVP_MD *md)
+{
+	EVP_MD_meth_free(md);
+}
+#endif /* LIBRESSL_VERSION_NUMBER */
+
+static int
+decode_bignum(const cbor_item_t *item, void *ptr, size_t len)
+{
+	if (cbor_isa_bytestring(item) == false ||
+	    cbor_bytestring_is_definite(item) == false ||
+	    cbor_bytestring_length(item) != len) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (-1);
+	}
+
+	memcpy(ptr, cbor_bytestring_handle(item), len);
+
+	return (0);
+}
+
+static int
+decode_rsa_pubkey(const cbor_item_t *key, const cbor_item_t *val, void *arg)
+{
+	rs256_pk_t *k = arg;
+
+	if (cbor_isa_negint(key) == false ||
+	    cbor_int_get_width(key) != CBOR_INT_8)
+		return (0); /* ignore */
+
+	switch (cbor_get_uint8(key)) {
+	case 0: /* modulus */
+		return (decode_bignum(val, &k->n, sizeof(k->n)));
+	case 1: /* public exponent */
+		return (decode_bignum(val, &k->e, sizeof(k->e)));
+	}
+
+	return (0); /* ignore */
+}
+
+int
+rs256_pk_decode(const cbor_item_t *item, rs256_pk_t *k)
+{
+	if (cbor_isa_map(item) == false ||
+	    cbor_map_is_definite(item) == false ||
+	    cbor_map_iter(item, k, decode_rsa_pubkey) < 0) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (-1);
+	}
+
+	return (0);
+}
+
+rs256_pk_t *
+rs256_pk_new(void)
+{
+	return (calloc(1, sizeof(rs256_pk_t)));
+}
+
+void
+rs256_pk_free(rs256_pk_t **pkp)
+{
+	rs256_pk_t *pk;
+
+	if (pkp == NULL || (pk = *pkp) == NULL)
+		return;
+
+	freezero(pk, sizeof(*pk));
+	*pkp = NULL;
+}
+
+int
+rs256_pk_from_ptr(rs256_pk_t *pk, const void *ptr, size_t len)
+{
+	EVP_PKEY *pkey;
+
+	if (len < sizeof(*pk))
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	memcpy(pk, ptr, sizeof(*pk));
+
+	if ((pkey = rs256_pk_to_EVP_PKEY(pk)) == NULL) {
+		fido_log_debug("%s: rs256_pk_to_EVP_PKEY", __func__);
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	}
+
+	EVP_PKEY_free(pkey);
+
+	return (FIDO_OK);
+}
+
+EVP_PKEY *
+rs256_pk_to_EVP_PKEY(const rs256_pk_t *k)
+{
+	RSA		*rsa = NULL;
+	EVP_PKEY	*pkey = NULL;
+	BIGNUM		*n = NULL;
+	BIGNUM		*e = NULL;
+	int		 ok = -1;
+
+	if ((n = BN_new()) == NULL || (e = BN_new()) == NULL)
+		goto fail;
+
+	if (BN_bin2bn(k->n, sizeof(k->n), n) == NULL ||
+	    BN_bin2bn(k->e, sizeof(k->e), e) == NULL) {
+		fido_log_debug("%s: BN_bin2bn", __func__);
+		goto fail;
+	}
+
+	if ((rsa = RSA_new()) == NULL || RSA_set0_key(rsa, n, e, NULL) == 0) {
+		fido_log_debug("%s: RSA_set0_key", __func__);
+		goto fail;
+	}
+
+	/* at this point, n and e belong to rsa */
+	n = NULL;
+	e = NULL;
+
+	if (RSA_bits(rsa) != 2048) {
+		fido_log_debug("%s: invalid key length", __func__);
+		goto fail;
+	}
+
+	if ((pkey = EVP_PKEY_new()) == NULL ||
+	    EVP_PKEY_assign_RSA(pkey, rsa) == 0) {
+		fido_log_debug("%s: EVP_PKEY_assign_RSA", __func__);
+		goto fail;
+	}
+
+	rsa = NULL; /* at this point, rsa belongs to evp */
+
+	ok = 0;
+fail:
+	if (n != NULL)
+		BN_free(n);
+	if (e != NULL)
+		BN_free(e);
+	if (rsa != NULL)
+		RSA_free(rsa);
+	if (ok < 0 && pkey != NULL) {
+		EVP_PKEY_free(pkey);
+		pkey = NULL;
+	}
+
+	return (pkey);
+}
+
+int
+rs256_pk_from_RSA(rs256_pk_t *pk, const RSA *rsa)
+{
+	const BIGNUM	*n = NULL;
+	const BIGNUM	*e = NULL;
+	const BIGNUM	*d = NULL;
+	int		 k;
+
+	if (RSA_bits(rsa) != 2048) {
+		fido_log_debug("%s: invalid key length", __func__);
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	}
+
+	RSA_get0_key(rsa, &n, &e, &d);
+
+	if (n == NULL || e == NULL) {
+		fido_log_debug("%s: RSA_get0_key", __func__);
+		return (FIDO_ERR_INTERNAL);
+	}
+
+	if ((k = BN_num_bytes(n)) < 0 || (size_t)k > sizeof(pk->n) ||
+	    (k = BN_num_bytes(e)) < 0 || (size_t)k > sizeof(pk->e)) {
+		fido_log_debug("%s: invalid key", __func__);
+		return (FIDO_ERR_INTERNAL);
+	}
+
+	if ((k = BN_bn2bin(n, pk->n)) < 0 || (size_t)k > sizeof(pk->n) ||
+	    (k = BN_bn2bin(e, pk->e)) < 0 || (size_t)k > sizeof(pk->e)) {
+		fido_log_debug("%s: BN_bn2bin", __func__);
+		return (FIDO_ERR_INTERNAL);
+	}
+
+	return (FIDO_OK);
+}
+
+int
+rs256_pk_from_EVP_PKEY(rs256_pk_t *pk, const EVP_PKEY *pkey)
+{
+	const RSA *rsa;
+
+	if (EVP_PKEY_base_id(pkey) != EVP_PKEY_RSA ||
+	    (rsa = get0_RSA(pkey)) == NULL)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	return (rs256_pk_from_RSA(pk, rsa));
+}
+
+int
+rs256_verify_sig(const fido_blob_t *dgst, EVP_PKEY *pkey,
+    const fido_blob_t *sig)
+{
+	EVP_PKEY_CTX	*pctx = NULL;
+	EVP_MD		*md = NULL;
+	int		 ok = -1;
+
+	if (EVP_PKEY_base_id(pkey) != EVP_PKEY_RSA) {
+		fido_log_debug("%s: EVP_PKEY_base_id", __func__);
+		goto fail;
+	}
+
+	if ((md = rs256_get_EVP_MD()) == NULL) {
+		fido_log_debug("%s: rs256_get_EVP_MD", __func__);
+		goto fail;
+	}
+
+	if ((pctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL ||
+	    EVP_PKEY_verify_init(pctx) != 1 ||
+	    EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PADDING) != 1 ||
+	    EVP_PKEY_CTX_set_signature_md(pctx, md) != 1) {
+		fido_log_debug("%s: EVP_PKEY_CTX", __func__);
+		goto fail;
+	}
+
+	if (EVP_PKEY_verify(pctx, sig->ptr, sig->len, dgst->ptr,
+	    dgst->len) != 1) {
+		fido_log_debug("%s: EVP_PKEY_verify", __func__);
+		goto fail;
+	}
+
+	ok = 0;
+fail:
+	EVP_PKEY_CTX_free(pctx);
+	rs256_free_EVP_MD(md);
+
+	return (ok);
+}
+
+int
+rs256_pk_verify_sig(const fido_blob_t *dgst, const rs256_pk_t *pk,
+    const fido_blob_t *sig)
+{
+	EVP_PKEY	*pkey;
+	int		 ok = -1;
+
+	if ((pkey = rs256_pk_to_EVP_PKEY(pk)) == NULL ||
+	    rs256_verify_sig(dgst, pkey, sig) < 0) {
+		fido_log_debug("%s: rs256_verify_sig", __func__);
+		goto fail;
+	}
+
+	ok = 0;
+fail:
+	EVP_PKEY_free(pkey);
+
+	return (ok);
+}