[bssl] Add HKDF wrapper to libbssl
Test: atest libbssl_avf_nostd.test
Bug: 301068421
Change-Id: Iffe99f3cb609215680b7d44bde8ae0ee5c502171
diff --git a/libs/bssl/error/src/lib.rs b/libs/bssl/error/src/lib.rs
index 1f9751f..68f7485 100644
--- a/libs/bssl/error/src/lib.rs
+++ b/libs/bssl/error/src/lib.rs
@@ -59,5 +59,6 @@
EC_KEY_marshal_private_key,
EC_KEY_new_by_curve_name,
EC_POINT_get_affine_coordinates,
+ HKDF,
HMAC,
}
diff --git a/libs/bssl/src/digest.rs b/libs/bssl/src/digest.rs
index 47e4aba..49e66e6 100644
--- a/libs/bssl/src/digest.rs
+++ b/libs/bssl/src/digest.rs
@@ -32,7 +32,6 @@
}
/// Returns a `Digester` implementing `SHA-512` algorithm.
- #[allow(dead_code)]
pub fn sha512() -> Self {
// SAFETY: This function does not access any Rust variables and simply returns
// a pointer to the static variable in BoringSSL.
diff --git a/libs/bssl/src/hkdf.rs b/libs/bssl/src/hkdf.rs
new file mode 100644
index 0000000..5dc6876
--- /dev/null
+++ b/libs/bssl/src/hkdf.rs
@@ -0,0 +1,49 @@
+// Copyright 2023, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Wrappers of the HKDF functions in BoringSSL hkdf.h.
+
+use crate::digest::Digester;
+use crate::util::check_int_result;
+use bssl_avf_error::{ApiName, Result};
+use bssl_ffi::HKDF;
+
+/// Computes HKDF (as specified by [RFC 5869]) of initial keying material `secret` with
+/// `salt` and `info` using the given `digester`.
+///
+/// [RFC 5869]: https://www.rfc-editor.org/rfc/rfc5869.html
+pub fn hkdf<const N: usize>(
+ secret: &[u8],
+ salt: &[u8],
+ info: &[u8],
+ digester: Digester,
+) -> Result<[u8; N]> {
+ let mut key = [0u8; N];
+ // SAFETY: Only reads from/writes to the provided slices and the digester was non-null.
+ let ret = unsafe {
+ HKDF(
+ key.as_mut_ptr(),
+ key.len(),
+ digester.0,
+ secret.as_ptr(),
+ secret.len(),
+ salt.as_ptr(),
+ salt.len(),
+ info.as_ptr(),
+ info.len(),
+ )
+ };
+ check_int_result(ret, ApiName::HKDF)?;
+ Ok(key)
+}
diff --git a/libs/bssl/src/lib.rs b/libs/bssl/src/lib.rs
index 1824080..4b9ff59 100644
--- a/libs/bssl/src/lib.rs
+++ b/libs/bssl/src/lib.rs
@@ -21,10 +21,13 @@
mod cbb;
mod digest;
mod ec_key;
+mod hkdf;
mod hmac;
mod util;
pub use bssl_avf_error::{ApiName, Error, Result};
pub use cbb::CbbFixed;
+pub use digest::Digester;
pub use ec_key::{EcKey, ZVec};
+pub use hkdf::hkdf;
pub use hmac::hmac_sha256;
diff --git a/libs/bssl/tests/hkdf_test.rs b/libs/bssl/tests/hkdf_test.rs
new file mode 100644
index 0000000..1cda042
--- /dev/null
+++ b/libs/bssl/tests/hkdf_test.rs
@@ -0,0 +1,95 @@
+// Copyright 2023, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Test HKDF with the test cases in [RFC 5869] Appendix A
+//!
+//! [RFC 5869]: https://datatracker.ietf.org/doc/html/rfc5869
+
+use bssl_avf::{hkdf, Digester, Result};
+
+#[test]
+fn rfc5869_test_case_1() -> Result<()> {
+ const IKM: [u8; 22] = [
+ 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+ 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+ ];
+ const SALT: [u8; 13] =
+ [0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c];
+ const INFO: [u8; 10] = [0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9];
+ const L: usize = 42;
+ const OKM: [u8; L] = [
+ 0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43, 0x4f, 0x64, 0xd0, 0x36, 0x2f,
+ 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a, 0x5a, 0x4c, 0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4,
+ 0xc5, 0xbf, 0x34, 0x00, 0x72, 0x08, 0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65,
+ ];
+ assert_eq!(OKM, hkdf::<L>(&IKM, &SALT, &INFO, Digester::sha256())?);
+ Ok(())
+}
+
+#[test]
+fn rfc5869_test_case_2() -> Result<()> {
+ const IKM: [u8; 80] = [
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+ 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
+ 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c,
+ 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+ 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
+ 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
+ ];
+ const SALT: [u8; 80] = [
+ 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e,
+ 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d,
+ 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c,
+ 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
+ 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa,
+ 0xab, 0xac, 0xad, 0xae, 0xaf,
+ ];
+ const INFO: [u8; 80] = [
+ 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe,
+ 0xbf, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd,
+ 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc,
+ 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb,
+ 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa,
+ 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+ ];
+ const L: usize = 82;
+ const OKM: [u8; L] = [
+ 0xb1, 0x1e, 0x39, 0x8d, 0xc8, 0x03, 0x27, 0xa1, 0xc8, 0xe7, 0xf7, 0x8c, 0x59, 0x6a, 0x49,
+ 0x34, 0x4f, 0x01, 0x2e, 0xda, 0x2d, 0x4e, 0xfa, 0xd8, 0xa0, 0x50, 0xcc, 0x4c, 0x19, 0xaf,
+ 0xa9, 0x7c, 0x59, 0x04, 0x5a, 0x99, 0xca, 0xc7, 0x82, 0x72, 0x71, 0xcb, 0x41, 0xc6, 0x5e,
+ 0x59, 0x0e, 0x09, 0xda, 0x32, 0x75, 0x60, 0x0c, 0x2f, 0x09, 0xb8, 0x36, 0x77, 0x93, 0xa9,
+ 0xac, 0xa3, 0xdb, 0x71, 0xcc, 0x30, 0xc5, 0x81, 0x79, 0xec, 0x3e, 0x87, 0xc1, 0x4c, 0x01,
+ 0xd5, 0xc1, 0xf3, 0x43, 0x4f, 0x1d, 0x87,
+ ];
+ assert_eq!(OKM, hkdf::<L>(&IKM, &SALT, &INFO, Digester::sha256())?);
+ Ok(())
+}
+
+#[test]
+fn rfc5869_test_case_3() -> Result<()> {
+ const IKM: [u8; 22] = [
+ 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+ 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+ ];
+ const SALT: [u8; 0] = [];
+ const INFO: [u8; 0] = [];
+ const L: usize = 42;
+ const OKM: [u8; L] = [
+ 0x8d, 0xa4, 0xe7, 0x75, 0xa5, 0x63, 0xc1, 0x8f, 0x71, 0x5f, 0x80, 0x2a, 0x06, 0x3c, 0x5a,
+ 0x31, 0xb8, 0xa1, 0x1f, 0x5c, 0x5e, 0xe1, 0x87, 0x9e, 0xc3, 0x45, 0x4e, 0x5f, 0x3c, 0x73,
+ 0x8d, 0x2d, 0x9d, 0x20, 0x13, 0x95, 0xfa, 0xa4, 0xb6, 0x1a, 0x96, 0xc8,
+ ];
+ assert_eq!(OKM, hkdf::<L>(&IKM, &SALT, &INFO, Digester::sha256())?);
+ Ok(())
+}
diff --git a/libs/bssl/tests/tests.rs b/libs/bssl/tests/tests.rs
index dc73c1e..1077787 100644
--- a/libs/bssl/tests/tests.rs
+++ b/libs/bssl/tests/tests.rs
@@ -14,4 +14,5 @@
//! API tests of the crate `bssl_avf`.
+mod hkdf_test;
mod hmac_test;