1 files changed, 28 insertions, 0 deletions
diff --git a/openpgp-ffi/src/packet/user_attribute.rs b/openpgp-ffi/src/packet/user_attribute.rs
new file mode 100644
index 00000000..ac552e65
--- /dev/null
+++ b/openpgp-ffi/src/packet/user_attribute.rs
@@ -0,0 +1,28 @@
+//! User Attribute packets.
+//!
+//! See [Section 5.12 of RFC 4880] for details.
+//!
+//!   [Section 5.12 of RFC 4880]: https://tools.ietf.org/html/rfc4880#section-5.12
+
+use libc::{uint8_t, size_t};
+extern crate sequoia_openpgp as openpgp;
+use self::openpgp::Packet;
+
+/// Returns the value of the User Attribute Packet.
+///
+/// The returned pointer is valid until `ua` is deallocated.  If
+/// `value_len` is not `NULL`, the size of value is stored there.
+#[::ffi_catch_abort] #[no_mangle]
+pub extern "system" fn pgp_user_attribute_value(ua: *const Packet,
+                                               value_len: Option<&mut size_t>)
+                                               -> *const uint8_t {
+    let ua = ffi_param_ref!(ua);
+    if let &Packet::UserAttribute(ref ua) = ua {
+        if let Some(p) = value_len {
+            *p = ua.user_attribute().len();
+        }
+        ua.user_attribute().as_ptr()
+    } else {
+        panic!("Not a UserAttribute packet");
+    }
+}