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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:23:06 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:23:06 +0000
commitcd13e2506379761d3464eae917eb1881876a7aa1 (patch)
tree54d32c05b0d6396408ff0d599d771fb9e7cdd60c /src/aes256.c
parentInitial commit. (diff)
downloadlibfido2-upstream.tar.xz
libfido2-upstream.zip
Adding upstream version 1.12.0.upstream/1.12.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--src/aes256.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/src/aes256.c b/src/aes256.c
new file mode 100644
index 0000000..dcf716d
--- /dev/null
+++ b/src/aes256.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2021 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 "fido.h"
+
+static int
+aes256_cbc(const fido_blob_t *key, const u_char *iv, const fido_blob_t *in,
+ fido_blob_t *out, int encrypt)
+{
+ EVP_CIPHER_CTX *ctx = NULL;
+ const EVP_CIPHER *cipher;
+ int ok = -1;
+
+ memset(out, 0, sizeof(*out));
+
+ if (key->len != 32) {
+ fido_log_debug("%s: invalid key len %zu", __func__, key->len);
+ goto fail;
+ }
+ if (in->len > UINT_MAX || in->len % 16 || in->len == 0) {
+ fido_log_debug("%s: invalid input len %zu", __func__, in->len);
+ goto fail;
+ }
+ out->len = in->len;
+ if ((out->ptr = calloc(1, out->len)) == NULL) {
+ fido_log_debug("%s: calloc", __func__);
+ goto fail;
+ }
+ if ((ctx = EVP_CIPHER_CTX_new()) == NULL ||
+ (cipher = EVP_aes_256_cbc()) == NULL) {
+ fido_log_debug("%s: EVP_CIPHER_CTX_new", __func__);
+ goto fail;
+ }
+ if (EVP_CipherInit(ctx, cipher, key->ptr, iv, encrypt) == 0 ||
+ EVP_Cipher(ctx, out->ptr, in->ptr, (u_int)out->len) < 0) {
+ fido_log_debug("%s: EVP_Cipher", __func__);
+ goto fail;
+ }
+
+ ok = 0;
+fail:
+ if (ctx != NULL)
+ EVP_CIPHER_CTX_free(ctx);
+ if (ok < 0)
+ fido_blob_reset(out);
+
+ return ok;
+}
+
+static int
+aes256_cbc_proto1(const fido_blob_t *key, const fido_blob_t *in,
+ fido_blob_t *out, int encrypt)
+{
+ u_char iv[16];
+
+ memset(&iv, 0, sizeof(iv));
+
+ return aes256_cbc(key, iv, in, out, encrypt);
+}
+
+static int
+aes256_cbc_fips(const fido_blob_t *secret, const fido_blob_t *in,
+ fido_blob_t *out, int encrypt)
+{
+ fido_blob_t key, cin, cout;
+ u_char iv[16];
+
+ memset(out, 0, sizeof(*out));
+
+ if (secret->len != 64) {
+ fido_log_debug("%s: invalid secret len %zu", __func__,
+ secret->len);
+ return -1;
+ }
+ if (in->len < sizeof(iv)) {
+ fido_log_debug("%s: invalid input len %zu", __func__, in->len);
+ return -1;
+ }
+ if (encrypt) {
+ if (fido_get_random(iv, sizeof(iv)) < 0) {
+ fido_log_debug("%s: fido_get_random", __func__);
+ return -1;
+ }
+ cin = *in;
+ } else {
+ memcpy(iv, in->ptr, sizeof(iv));
+ cin.ptr = in->ptr + sizeof(iv);
+ cin.len = in->len - sizeof(iv);
+ }
+ key.ptr = secret->ptr + 32;
+ key.len = secret->len - 32;
+ if (aes256_cbc(&key, iv, &cin, &cout, encrypt) < 0)
+ return -1;
+ if (encrypt) {
+ if (cout.len > SIZE_MAX - sizeof(iv) ||
+ (out->ptr = calloc(1, sizeof(iv) + cout.len)) == NULL) {
+ fido_blob_reset(&cout);
+ return -1;
+ }
+ out->len = sizeof(iv) + cout.len;
+ memcpy(out->ptr, iv, sizeof(iv));
+ memcpy(out->ptr + sizeof(iv), cout.ptr, cout.len);
+ fido_blob_reset(&cout);
+ } else
+ *out = cout;
+
+ return 0;
+}
+
+static int
+aes256_gcm(const fido_blob_t *key, const fido_blob_t *nonce,
+ const fido_blob_t *aad, const fido_blob_t *in, fido_blob_t *out,
+ int encrypt)
+{
+ EVP_CIPHER_CTX *ctx = NULL;
+ const EVP_CIPHER *cipher;
+ size_t textlen;
+ int ok = -1;
+
+ memset(out, 0, sizeof(*out));
+
+ if (nonce->len != 12 || key->len != 32 || aad->len > UINT_MAX) {
+ fido_log_debug("%s: invalid params %zu, %zu, %zu", __func__,
+ nonce->len, key->len, aad->len);
+ goto fail;
+ }
+ if (in->len > UINT_MAX || in->len > SIZE_MAX - 16 || in->len < 16) {
+ fido_log_debug("%s: invalid input len %zu", __func__, in->len);
+ goto fail;
+ }
+ /* add tag to (on encrypt) or trim tag from the output (on decrypt) */
+ out->len = encrypt ? in->len + 16 : in->len - 16;
+ if ((out->ptr = calloc(1, out->len)) == NULL) {
+ fido_log_debug("%s: calloc", __func__);
+ goto fail;
+ }
+ if ((ctx = EVP_CIPHER_CTX_new()) == NULL ||
+ (cipher = EVP_aes_256_gcm()) == NULL) {
+ fido_log_debug("%s: EVP_CIPHER_CTX_new", __func__);
+ goto fail;
+ }
+ if (EVP_CipherInit(ctx, cipher, key->ptr, nonce->ptr, encrypt) == 0) {
+ fido_log_debug("%s: EVP_CipherInit", __func__);
+ goto fail;
+ }
+
+ if (encrypt)
+ textlen = in->len;
+ else {
+ textlen = in->len - 16;
+ /* point openssl at the mac tag */
+ if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, 16,
+ in->ptr + in->len - 16) == 0) {
+ fido_log_debug("%s: EVP_CIPHER_CTX_ctrl", __func__);
+ goto fail;
+ }
+ }
+ /* the last EVP_Cipher() will either compute or verify the mac tag */
+ if (EVP_Cipher(ctx, NULL, aad->ptr, (u_int)aad->len) < 0 ||
+ EVP_Cipher(ctx, out->ptr, in->ptr, (u_int)textlen) < 0 ||
+ EVP_Cipher(ctx, NULL, NULL, 0) < 0) {
+ fido_log_debug("%s: EVP_Cipher", __func__);
+ goto fail;
+ }
+ if (encrypt) {
+ /* append the mac tag */
+ if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, 16,
+ out->ptr + out->len - 16) == 0) {
+ fido_log_debug("%s: EVP_CIPHER_CTX_ctrl", __func__);
+ goto fail;
+ }
+ }
+
+ ok = 0;
+fail:
+ if (ctx != NULL)
+ EVP_CIPHER_CTX_free(ctx);
+ if (ok < 0)
+ fido_blob_reset(out);
+
+ return ok;
+}
+
+int
+aes256_cbc_enc(const fido_dev_t *dev, const fido_blob_t *secret,
+ const fido_blob_t *in, fido_blob_t *out)
+{
+ return fido_dev_get_pin_protocol(dev) == 2 ? aes256_cbc_fips(secret,
+ in, out, 1) : aes256_cbc_proto1(secret, in, out, 1);
+}
+
+int
+aes256_cbc_dec(const fido_dev_t *dev, const fido_blob_t *secret,
+ const fido_blob_t *in, fido_blob_t *out)
+{
+ return fido_dev_get_pin_protocol(dev) == 2 ? aes256_cbc_fips(secret,
+ in, out, 0) : aes256_cbc_proto1(secret, in, out, 0);
+}
+
+int
+aes256_gcm_enc(const fido_blob_t *key, const fido_blob_t *nonce,
+ const fido_blob_t *aad, const fido_blob_t *in, fido_blob_t *out)
+{
+ return aes256_gcm(key, nonce, aad, in, out, 1);
+}
+
+int
+aes256_gcm_dec(const fido_blob_t *key, const fido_blob_t *nonce,
+ const fido_blob_t *aad, const fido_blob_t *in, fido_blob_t *out)
+{
+ return aes256_gcm(key, nonce, aad, in, out, 0);
+}