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diff --git a/vendor/openssl/src/derive.rs b/vendor/openssl/src/derive.rs
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+//! Shared secret derivation.
+//!
+//! # Example
+//!
+//! The following example implements [ECDH] using `NIST P-384` keys:
+//!
+//! ```
+//! # fn main() -> Result<(), Box<dyn std::error::Error>> {
+//! # use std::convert::TryInto;
+//! use openssl::bn::BigNumContext;
+//! use openssl::pkey::PKey;
+//! use openssl::derive::Deriver;
+//! use openssl::ec::{EcGroup, EcKey, EcPoint, PointConversionForm};
+//! use openssl::nid::Nid;
+//!
+//! let group = EcGroup::from_curve_name(Nid::SECP384R1)?;
+//!
+//! let first: PKey<_> = EcKey::generate(&group)?.try_into()?;
+//!
+//! // second party generates an ephemeral key and derives
+//! // a shared secret using first party's public key
+//! let shared_key = EcKey::generate(&group)?;
+//! // shared_public is sent to first party
+//! let mut ctx = BigNumContext::new()?;
+//! let shared_public = shared_key.public_key().to_bytes(
+//!        &group,
+//!        PointConversionForm::COMPRESSED,
+//!        &mut ctx,
+//!    )?;
+//!
+//! let shared_key: PKey<_> = shared_key.try_into()?;
+//! let mut deriver = Deriver::new(&shared_key)?;
+//! deriver.set_peer(&first)?;
+//! // secret can be used e.g. as a symmetric encryption key
+//! let secret = deriver.derive_to_vec()?;
+//! # drop(deriver);
+//!
+//! // first party derives the same shared secret using
+//! // shared_public
+//! let point = EcPoint::from_bytes(&group, &shared_public, &mut ctx)?;
+//! let recipient_key: PKey<_> = EcKey::from_public_key(&group, &point)?.try_into()?;
+//! let mut deriver = Deriver::new(&first)?;
+//! deriver.set_peer(&recipient_key)?;
+//! let first_secret = deriver.derive_to_vec()?;
+//!
+//! assert_eq!(secret, first_secret);
+//! # Ok(()) }
+//! ```
+//!
+//! [ECDH]: https://wiki.openssl.org/index.php/Elliptic_Curve_Diffie_Hellman
+
+use foreign_types::ForeignTypeRef;
+use std::marker::PhantomData;
+use std::ptr;
+
+use crate::error::ErrorStack;
+use crate::pkey::{HasPrivate, HasPublic, PKeyRef};
+use crate::{cvt, cvt_p};
+use openssl_macros::corresponds;
+
+/// A type used to derive a shared secret between two keys.
+pub struct Deriver<'a>(*mut ffi::EVP_PKEY_CTX, PhantomData<&'a ()>);
+
+unsafe impl<'a> Sync for Deriver<'a> {}
+unsafe impl<'a> Send for Deriver<'a> {}
+
+#[allow(clippy::len_without_is_empty)]
+impl<'a> Deriver<'a> {
+    /// Creates a new `Deriver` using the provided private key.
+    ///
+    /// This corresponds to [`EVP_PKEY_derive_init`].
+    ///
+    /// [`EVP_PKEY_derive_init`]: https://www.openssl.org/docs/manmaster/crypto/EVP_PKEY_derive_init.html
+    pub fn new<T>(key: &'a PKeyRef<T>) -> Result<Deriver<'a>, ErrorStack>
+    where
+        T: HasPrivate,
+    {
+        unsafe {
+            cvt_p(ffi::EVP_PKEY_CTX_new(key.as_ptr(), ptr::null_mut()))
+                .map(|p| Deriver(p, PhantomData))
+                .and_then(|ctx| cvt(ffi::EVP_PKEY_derive_init(ctx.0)).map(|_| ctx))
+        }
+    }
+
+    /// Sets the peer key used for secret derivation.
+    #[corresponds(EVP_PKEY_derive_set_peer)]
+    pub fn set_peer<T>(&mut self, key: &'a PKeyRef<T>) -> Result<(), ErrorStack>
+    where
+        T: HasPublic,
+    {
+        unsafe { cvt(ffi::EVP_PKEY_derive_set_peer(self.0, key.as_ptr())).map(|_| ()) }
+    }
+
+    /// Sets the peer key used for secret derivation along with optionally validating the peer public key.
+    ///
+    /// Requires OpenSSL 3.0.0 or newer.
+    #[corresponds(EVP_PKEY_derive_set_peer_ex)]
+    #[cfg(ossl300)]
+    pub fn set_peer_ex<T>(
+        &mut self,
+        key: &'a PKeyRef<T>,
+        validate_peer: bool,
+    ) -> Result<(), ErrorStack>
+    where
+        T: HasPublic,
+    {
+        unsafe {
+            cvt(ffi::EVP_PKEY_derive_set_peer_ex(
+                self.0,
+                key.as_ptr(),
+                validate_peer as i32,
+            ))
+            .map(|_| ())
+        }
+    }
+
+    /// Returns the size of the shared secret.
+    ///
+    /// It can be used to size the buffer passed to [`Deriver::derive`].
+    ///
+    /// This corresponds to [`EVP_PKEY_derive`].
+    ///
+    /// [`Deriver::derive`]: #method.derive
+    /// [`EVP_PKEY_derive`]: https://www.openssl.org/docs/manmaster/crypto/EVP_PKEY_derive_init.html
+    pub fn len(&mut self) -> Result<usize, ErrorStack> {
+        unsafe {
+            let mut len = 0;
+            cvt(ffi::EVP_PKEY_derive(self.0, ptr::null_mut(), &mut len)).map(|_| len)
+        }
+    }
+
+    /// Derives a shared secret between the two keys, writing it into the buffer.
+    ///
+    /// Returns the number of bytes written.
+    ///
+    /// This corresponds to [`EVP_PKEY_derive`].
+    ///
+    /// [`EVP_PKEY_derive`]: https://www.openssl.org/docs/manmaster/crypto/EVP_PKEY_derive_init.html
+    pub fn derive(&mut self, buf: &mut [u8]) -> Result<usize, ErrorStack> {
+        let mut len = buf.len();
+        unsafe {
+            cvt(ffi::EVP_PKEY_derive(
+                self.0,
+                buf.as_mut_ptr() as *mut _,
+                &mut len,
+            ))
+            .map(|_| len)
+        }
+    }
+
+    /// A convenience function which derives a shared secret and returns it in a new buffer.
+    ///
+    /// This simply wraps [`Deriver::len`] and [`Deriver::derive`].
+    ///
+    /// [`Deriver::len`]: #method.len
+    /// [`Deriver::derive`]: #method.derive
+    pub fn derive_to_vec(&mut self) -> Result<Vec<u8>, ErrorStack> {
+        let len = self.len()?;
+        let mut buf = vec![0; len];
+        let len = self.derive(&mut buf)?;
+        buf.truncate(len);
+        Ok(buf)
+    }
+}
+
+impl<'a> Drop for Deriver<'a> {
+    fn drop(&mut self) {
+        unsafe {
+            ffi::EVP_PKEY_CTX_free(self.0);
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    use crate::ec::{EcGroup, EcKey};
+    use crate::nid::Nid;
+    use crate::pkey::PKey;
+
+    #[test]
+    fn derive_without_peer() {
+        let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
+        let ec_key = EcKey::generate(&group).unwrap();
+        let pkey = PKey::from_ec_key(ec_key).unwrap();
+        let mut deriver = Deriver::new(&pkey).unwrap();
+        deriver.derive_to_vec().unwrap_err();
+    }
+
+    #[test]
+    fn test_ec_key_derive() {
+        let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
+        let ec_key = EcKey::generate(&group).unwrap();
+        let ec_key2 = EcKey::generate(&group).unwrap();
+        let pkey = PKey::from_ec_key(ec_key).unwrap();
+        let pkey2 = PKey::from_ec_key(ec_key2).unwrap();
+        let mut deriver = Deriver::new(&pkey).unwrap();
+        deriver.set_peer(&pkey2).unwrap();
+        let shared = deriver.derive_to_vec().unwrap();
+        assert!(!shared.is_empty());
+    }
+
+    #[test]
+    #[cfg(ossl300)]
+    fn test_ec_key_derive_ex() {
+        let group = EcGroup::from_curve_name(Nid::X9_62_PRIME256V1).unwrap();
+        let ec_key = EcKey::generate(&group).unwrap();
+        let ec_key2 = EcKey::generate(&group).unwrap();
+        let pkey = PKey::from_ec_key(ec_key).unwrap();
+        let pkey2 = PKey::from_ec_key(ec_key2).unwrap();
+        let mut deriver = Deriver::new(&pkey).unwrap();
+        deriver.set_peer_ex(&pkey2, true).unwrap();
+        let shared = deriver.derive_to_vec().unwrap();
+        assert!(!shared.is_empty());
+    }
+}