NFC: Use core::ffi::{c_int,c_uint}.

We can use these after the recent MSRV bump.

src/aead/aes.rs

@@ -24,7 +24,7 @@ use crate::{
     error,
     polyfill::{self, ArraySplitMap},
 };
-use core::ops::RangeFrom;
+use core::{ffi, ops::RangeFrom};
 
 #[derive(Clone)]
 pub(super) struct Key {
@@ -35,22 +35,22 @@ pub(super) struct Key {
 macro_rules! set_encrypt_key {
     ( $name:ident, $bytes:expr, $key_bits:expr, $key:expr ) => {{
         prefixed_extern! {
-            fn $name(user_key: *const u8, bits: c::uint, key: &mut AES_KEY) -> c::int;
+            fn $name(user_key: *const u8, bits: ffi::c_uint, key: &mut AES_KEY) -> ffi::c_int;
         }
         set_encrypt_key($name, $bytes, $key_bits, $key)
     }};
 }
 
 #[inline]
 fn set_encrypt_key(
-    f: unsafe extern "C" fn(*const u8, c::uint, &mut AES_KEY) -> c::int,
+    f: unsafe extern "C" fn(*const u8, ffi::c_uint, &mut AES_KEY) -> ffi::c_int,
     bytes: &[u8],
     key_bits: BitLength,
     key: &mut AES_KEY,
 ) -> Result<(), error::Unspecified> {
     // Unusually, in this case zero means success and non-zero means failure.
     #[allow(clippy::cast_possible_truncation)]
-    if 0 == unsafe { f(bytes.as_ptr(), key_bits.as_usize_bits() as c::uint, key) } {
+    if 0 == unsafe { f(bytes.as_ptr(), key_bits.as_usize_bits() as ffi::c_uint, key) } {
         Ok(())
     } else {
         Err(error::Unspecified)
@@ -312,7 +312,7 @@ impl Key {
 #[derive(Clone)]
 pub(super) struct AES_KEY {
     pub rd_key: [u32; 4 * (MAX_ROUNDS + 1)],
-    pub rounds: c::uint,
+    pub rounds: ffi::c_uint,
 }
 
 // Keep this in sync with `AES_MAXNR` in aes.h.

src/bssl.rs

@@ -12,15 +12,16 @@
 // OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
-use crate::{c, error};
+use crate::error;
+use core::ffi;
 
 /// An `int` returned from a foreign function containing **1** if the function
 /// was successful or **0** if an error occurred. This is the convention used by
 /// C code in `ring`.
 #[derive(Clone, Copy, Debug)]
 #[must_use]
 #[repr(transparent)]
-pub struct Result(c::int);
+pub struct Result(ffi::c_int);
 
 impl From<Result> for core::result::Result<(), error::Unspecified> {
     fn from(ret: Result) -> Self {
@@ -37,12 +38,12 @@ impl From<Result> for core::result::Result<(), error::Unspecified> {
 #[cfg(test)]
 mod tests {
     mod result {
-        use crate::{bssl, c};
-        use core::mem;
+        use crate::bssl;
+        use core::{ffi, mem};
 
         #[test]
         fn size_and_alignment() {
-            type Underlying = c::int;
+            type Underlying = ffi::c_int;
             assert_eq!(mem::size_of::<bssl::Result>(), mem::size_of::<Underlying>());
             assert_eq!(
                 mem::align_of::<bssl::Result>(),

src/c.rs

@@ -25,26 +25,13 @@
 
 // Keep in sync with the checks in base.h that verify these assumptions.
 
-pub(crate) type int = i32;
-pub(crate) type uint = u32;
 pub(crate) type size_t = usize;
 
 #[cfg(all(test, any(unix, windows)))]
 mod tests {
     use crate::c;
-
     #[test]
     fn test_libc_compatible() {
-        {
-            let x: c::int = 1;
-            let _x: libc::c_int = x;
-        }
-
-        {
-            let x: c::uint = 1;
-            let _x: libc::c_uint = x;
-        }
-
         {
             let x: c::size_t = 1;
             let _x: libc::size_t = x;

src/constant_time.rs

@@ -15,6 +15,7 @@
 //! Constant-time operations.
 
 use crate::{c, error};
+use core::ffi;
 
 /// Returns `Ok(())` if `a == b` and `Err(error::Unspecified)` otherwise.
 /// The comparison of `a` and `b` is done in constant time with respect to the
@@ -32,7 +33,7 @@ pub fn verify_slices_are_equal(a: &[u8], b: &[u8]) -> Result<(), error::Unspecif
 }
 
 prefixed_extern! {
-    fn CRYPTO_memcmp(a: *const u8, b: *const u8, len: c::size_t) -> c::int;
+    fn CRYPTO_memcmp(a: *const u8, b: *const u8, len: c::size_t) -> ffi::c_int;
 }
 
 #[cfg(test)]

src/ec/curve25519/ops.rs

@@ -17,10 +17,10 @@
 
 pub use super::scalar::{MaskedScalar, Scalar, SCALAR_LEN};
 use crate::{
-    bssl, c, cpu, error,
+    bssl, cpu, error,
     limb::{Limb, LIMB_BITS},
 };
-use core::marker::PhantomData;
+use core::{ffi, marker::PhantomData};
 
 // Elem<T>` is `fe` in curve25519/internal.h.
 // Elem<L> is `fe_loose` in curve25519/internal.h.
@@ -82,7 +82,7 @@ impl ExtPoint {
             t: Elem::zero(),
         };
         prefixed_extern! {
-            fn x25519_ge_scalarmult_base(h: &mut ExtPoint, a: &Scalar, has_fe25519_adx: c::int);
+            fn x25519_ge_scalarmult_base(h: &mut ExtPoint, a: &Scalar, has_fe25519_adx: ffi::c_int);
         }
         unsafe {
             x25519_ge_scalarmult_base(&mut r, scalar, has_fe25519_adx(cpu).into());

src/ec/curve25519/x25519.rs

@@ -15,7 +15,8 @@
 //! X25519 Key agreement.
 
 use super::{ops, scalar::SCALAR_LEN};
-use crate::{agreement, c, constant_time, cpu, ec, error, rand};
+use crate::{agreement, constant_time, cpu, ec, error, rand};
+use core::ffi;
 
 static CURVE25519: ec::Curve = ec::Curve {
     public_key_len: PUBLIC_KEY_LEN,
@@ -79,7 +80,7 @@ fn x25519_public_from_private(
         fn x25519_public_from_private_generic_masked(
             public_key_out: &mut PublicKey,
             private_key: &PrivateKey,
-            use_adx: c::int,
+            use_adx: ffi::c_int,
         );
     }
     unsafe {