Add AES_wrap_key and AES_unwrap_key functionality (b9341856) · Commits · Public Repositories / Rust Openssl

openssl-sys/src/aes.rs

+16 −0

Original line number	Diff line number	Diff line
		@@ -25,4 +25,20 @@ extern "C" {
		ivec: *mut c_uchar,
		enc: c_int,
		);

		pub fn AES_wrap_key(
		key: *mut AES_KEY,
		iv: *const c_uchar,
		out: *mut c_uchar,
		in_: *const c_uchar,
		inlen: c_uint,
		) -> c_int;

		pub fn AES_unwrap_key(
		key: *mut AES_KEY,
		iv: *const c_uchar,
		out: *mut c_uchar,
		in_: *const c_uchar,
		inlen: c_uint,
		) -> c_int;
		}

openssl/src/aes.rs

+115 −3

Original line number	Diff line number	Diff line
		//! Low level AES IGE functionality
		//! Low level AES IGE and key wrapping functionality
		//!
		//! AES ECB, CBC, XTS, CTR, CFB, GCM and other conventional symmetric encryption
		//! modes are found in [`symm`]. This is the implementation of AES IGE.
		//! modes are found in [`symm`]. This is the implementation of AES IGE and key wrapping
		//!
		//! Advanced Encryption Standard (AES) provides symmetric key cipher that
		//! the same key is used to encrypt and decrypt data. This implementation
		@@ -22,6 +22,7 @@
		//!
		//! # Examples
		//!
		//! ## AES IGE
		//! ```rust
		//! use openssl::aes::{AesKey, aes_ige};
		//! use openssl::symm::Mode;
		@@ -35,10 +36,31 @@
		//! let mut output = [0u8; 16];
		//! aes_ige(plaintext, &mut output, &key, &mut iv, Mode::Encrypt);
		//! assert_eq!(output, *b"\xa6\xad\x97\x4d\x5c\xea\x1d\x36\xd2\xf3\x67\x98\x09\x07\xed\x32");
		//! ```
		//!
		//! ## Key wrapping
		//! ```rust
		//! use openssl::aes::{AesKey, unwrap_key, wrap_key};
		//!
		//! let kek = b"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F";
		//! let key_to_wrap = b"\x00\x11\x22\x33\x44\x55\x66\x77\x88\x99\xAA\xBB\xCC\xDD\xEE\xFF";
		//!
		//! let enc_key = AesKey::new_encrypt(kek).unwrap();
		//! let mut ciphertext = [0u8; 24];
		//! wrap_key(&enc_key, None, &mut ciphertext, &key_to_wrap[..]).unwrap();
		//! let dec_key = AesKey::new_decrypt(kek).unwrap();
		//! let mut orig_key = [0u8; 16];
		//! unwrap_key(&dec_key, None, &mut orig_key, &ciphertext[..]).unwrap();
		//!
		//! assert_eq!(&orig_key[..], &key_to_wrap[..]);
		//! ```
		//!
		use ffi;
		use libc::c_int;
		use libc::{c_int, c_uint};
		use std::mem;

		use cvt;
		use error::ErrorStack;
		use symm::Mode;

		/// Provides Error handling for parsing keys.
		@@ -136,6 +158,70 @@ pub fn aes_ige(in_: &[u8], out: &mut [u8], key: &AesKey, iv: &mut [u8], mode: Mo
		}
		}

		/// Wrap a key, according to [RFC 3394](https://tools.ietf.org/html/rfc3394)
		///
		/// * `key`: The key-encrypting-key to use. Must be a encrypting key
		/// * `iv`: The IV to use. You must use the same IV for both wrapping and unwrapping
		/// * `out`: The output buffer to store the ciphertext
		/// * `in_`: The input buffer, storing the key to be wrapped
		///
		/// # Panics
		///
		/// Panics if either `out` or `in_` do not have sizes that are a multiple of 8, or if
		/// `out` is not 8 bytes longer than `in_`.
		pub fn wrap_key(
		key: &AesKey,
		iv: Option<[u8; 8]>,
		out: &mut [u8],
		in_: &[u8],
		) -> Result<usize, ErrorStack> {
		unsafe {
		assert!(out.len() == in_.len() + 8); // Ciphertext is 64 bits longer (see 2.2.1)
		assert!(in_.len() % 8 == 0); // Input (and hence output, given above) are integer multiples of 64 bit values

		cvt(ffi::AES_wrap_key(
		&key.0 as const _ as mut _, // this is safe, the implementation only uses the key as a const pointer.
		iv.map_or(std::ptr::null(), \|iv\| iv.as_ptr() as *const _),
		out.as_ptr() as *mut _,
		in_.as_ptr() as *const _,
		in_.len() as c_uint,
		))
		.map(\|written\| written as usize) // convert is safe, cvt only return ok with positive numbers
		}
		}

		/// Unwrap a key, according to [RFC 3394](https://tools.ietf.org/html/rfc3394)
		///
		/// * `key`: The key-encrypting-key to decrypt the wrapped key. Must be a decrypting key
		/// * `iv`: The same IV used for wrapping the key
		/// * `out`: The buffer to write the unwrapped key to
		/// * `in_`: The input ciphertext
		///
		/// # Panics
		///
		/// Panics if either `out` or `in_` do not have sizes that are a multiple of 8, or
		/// if `in` is not 8 bytes longer than `in_`.
		pub fn unwrap_key(
		key: &AesKey,
		iv: Option<[u8; 8]>,
		out: &mut [u8],
		in_: &[u8],
		) -> Result<usize, ErrorStack> {
		unsafe {
		assert!(in_.len() == out.len() + 8);
		assert!(in_.len() % 8 == 0);

		cvt(ffi::AES_unwrap_key(
		&key.0 as const _ as mut _, // this is safe, the implementation only uses the key as a const pointer.
		iv.map_or(std::ptr::null(), \|iv\| iv.as_ptr() as *const _),
		out.as_ptr() as *mut _,
		in_.as_ptr() as *const _,
		in_.len() as c_uint,
		))
		.map(\|written\| written as usize)
		}
		}

		#[cfg(test)]
		mod test {
		use hex::FromHex;
		@@ -166,4 +252,30 @@ mod test {
		aes_ige(&ct, &mut pt_actual, &key, &mut iv, Mode::Decrypt);
		assert_eq!(pt_actual, pt);
		}

		// from the RFC https://tools.ietf.org/html/rfc3394#section-2.2.3
		#[test]
		fn test_wrap_unwrap() {
		let raw_key = Vec::from_hex("000102030405060708090A0B0C0D0E0F").unwrap();
		let key_data = Vec::from_hex("00112233445566778899AABBCCDDEEFF").unwrap();
		let expected_ciphertext =
		Vec::from_hex("1FA68B0A8112B447AEF34BD8FB5A7B829D3E862371D2CFE5").unwrap();

		let enc_key = AesKey::new_encrypt(&raw_key).unwrap();
		let mut wrapped = [0; 24];
		assert_eq!(
		wrap_key(&enc_key, None, &mut wrapped, &key_data).unwrap(),
		24
		);
		assert_eq!(&wrapped[..], &expected_ciphertext[..]);

		let dec_key = AesKey::new_decrypt(&raw_key).unwrap();
		let mut unwrapped = [0; 16];
		assert_eq!(
		unwrap_key(&dec_key, None, &mut unwrapped, &wrapped).unwrap(),
		16
		);
		assert_eq!(&unwrapped[..], &key_data[..]);
		}

		}