chore: add vendor directory

1 files changed, 45 insertions, 0 deletions

diff --git a/vendor/getrandom/src/backends/windows7.rs b/vendor/getrandom/src/backends/windows7.rs
new file mode 100644
index 00000000..8a353a9f
--- /dev/null
+++ b/vendor/getrandom/src/backends/windows7.rs
@@ -0,0 +1,45 @@
+//! Legacy implementation for Windows XP and later
+//!
+//! For targets where we cannot use ProcessPrng (added in Windows 10), we use
+//! RtlGenRandom. See windows.rs for a more detailed discussion of the Windows
+//! RNG APIs (and why we don't use BCryptGenRandom). On versions prior to
+//! Windows 10, this implementation is secure. On Windows 10 and later, this
+//! implementation behaves identically to the windows.rs implementation, except
+//! that it forces the loading of an additonal DLL (advapi32.dll).
+//!
+//! This implementation will not work on UWP targets (which lack advapi32.dll),
+//! but such targets require Windows 10, so can use the standard implementation.
+use crate::Error;
+use core::{ffi::c_void, mem::MaybeUninit};
+
+pub use crate::util::{inner_u32, inner_u64};
+
+// Binding to the Windows.Win32.Security.Authentication.Identity.RtlGenRandom
+// API. Don't use windows-targets as it doesn't support Windows 7 targets.
+#[link(name = "advapi32")]
+extern "system" {
+    #[link_name = "SystemFunction036"]
+    fn RtlGenRandom(randombuffer: *mut c_void, randombufferlength: u32) -> BOOLEAN;
+}
+#[allow(clippy::upper_case_acronyms)]
+type BOOLEAN = u8;
+const TRUE: BOOLEAN = 1u8;
+
+#[inline]
+pub fn fill_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> {
+    // Prevent overflow of u32
+    let chunk_size = usize::try_from(i32::MAX).expect("Windows does not support 16-bit targets");
+    for chunk in dest.chunks_mut(chunk_size) {
+        let chunk_len = u32::try_from(chunk.len()).expect("chunk size is bounded by i32::MAX");
+        let ret = unsafe { RtlGenRandom(chunk.as_mut_ptr().cast::<c_void>(), chunk_len) };
+        if ret != TRUE {
+            return Err(Error::WINDOWS_RTL_GEN_RANDOM);
+        }
+    }
+    Ok(())
+}
+
+impl Error {
+    /// Call to Windows [`RtlGenRandom`](https://docs.microsoft.com/en-us/windows/win32/api/ntsecapi/nf-ntsecapi-rtlgenrandom) failed.
+    pub(crate) const WINDOWS_RTL_GEN_RANDOM: Error = Self::new_internal(10);
+}