Prepare for the possibility of this being usable with an MSRV bump

.github/workflows/ci.yml

@@ -66,7 +66,7 @@ jobs:
       matrix:
         RUST:
           # MSRV
-          - VERSION: "1.41.0"
+          - VERSION: "1.47.0"
             FLAGS: "--no-default-features --features std,derive"
           - VERSION: stable
             FLAGS: ""

Cargo.toml

@@ -17,7 +17,6 @@ derive = ["asn1_derive"]
 [dependencies]
 chrono = { version = "0.4", default-features = false, features = ["alloc"] }
 asn1_derive = { path = "asn1_derive/", version = "0.8.7", optional = true }
-proc-macro-hack = "0.5"
 
 [dev-dependencies]
 libc = "0.2"

asn1_derive/Cargo.toml

@@ -14,4 +14,3 @@ proc-macro = true
 proc-macro2 = "1.0"
 quote = "1.0"
 syn = { version = "1.0", features = ["parsing", "extra-traits"] }
-proc-macro-hack = "0.5"

asn1_derive/src/lib.rs

@@ -441,6 +441,8 @@ fn generate_enum_write_block(name: &syn::Ident, data: &syn::DataEnum) -> proc_ma
     }
 }
 
+// TODO: Duplicate of this function in src/object_identifier.rs, can we
+// de-dupe?
 fn _write_base128_int(data: &mut Vec<u8>, n: u32) {
     if n == 0 {
         data.push(0);
@@ -464,7 +466,7 @@ fn _write_base128_int(data: &mut Vec<u8>, n: u32) {
     }
 }
 
-#[proc_macro_hack::proc_macro_hack]
+#[proc_macro]
 pub fn oid(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let p_arcs = Punctuated::<syn::LitInt, syn::Token![,]>::parse_terminated
         .parse(item)
@@ -480,7 +482,8 @@ pub fn oid(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
     }
 
     let der_len = der_encoded.len();
-    der_encoded.resize(32, 0);
+    // TODO: is there a way to use the `MAX_OID_LENGTH` constant here?
+    der_encoded.resize(63, 0);
     let der_lit = syn::LitByteStr::new(&der_encoded, proc_macro2::Span::call_site());
     let expanded = quote::quote! {
         asn1::ObjectIdentifier::from_der_unchecked(*#der_lit, #der_len as u8)

src/lib.rs

@@ -121,10 +121,7 @@ pub use crate::types::{Explicit, Implicit};
 pub use crate::writer::{write, write_single, Writer};
 
 #[cfg(feature = "derive")]
-#[proc_macro_hack::proc_macro_hack(only_hack_old_rustc)]
-pub use asn1_derive::oid;
-#[cfg(feature = "derive")]
-pub use asn1_derive::{Asn1Read, Asn1Write};
+pub use asn1_derive::{oid, Asn1Read, Asn1Write};
 
 /// Decodes an `OPTIONAL` ASN.1 value which has a `DEFAULT`. Generaly called
 /// immediately after [`Parser::read_element`].

src/object_identifier.rs

@@ -1,7 +1,7 @@
 use crate::parser::{ParseError, ParseErrorKind, ParseResult};
 use alloc::fmt;
 
-const MAX_OID_LENGTH: usize = 32;
+const MAX_OID_LENGTH: usize = 63;
 
 /// Represents an ASN.1 `OBJECT IDENTIFIER`. ObjectIdentifiers are opaque, the only thing may be
 /// done with them is test if they are equal to another `ObjectIdentifier`. The generally
@@ -165,7 +165,7 @@ mod tests {
             ".2.5",
             "2..5",
             "2.5.",
-            "1.3.6.1.4.1.1248.1.1.2.1.3.21.69.112.115.111.110.32.83.116.121.108.117.115.32.80.114.111.32.52.57.48.48.123.124412.31.213321.123",
+            "1.3.6.1.4.1.1248.1.1.2.1.3.21.69.112.115.111.110.32.83.116.121.108.117.115.32.80.114.111.32.52.57.48.48.123.124412.31.213321.123.110.32.83.116.121.108.117.115.32.80.114.111.32.52.57.48.48.123.124412.31.213321.123",
         ] {
             assert_eq!(ObjectIdentifier::from_string(val), None);
         }
@@ -184,7 +184,7 @@ mod tests {
 
     #[test]
     fn test_from_der() {
-        assert_eq!(ObjectIdentifier::from_der(b"\x06\x2b\x2b\x06\x01\x04\x01\x89\x60\x01\x01\x02\x01\x03\x15\x45\x70\x73\x6f\x6e\x20\x53\x74\x79\x6c\x75\x73\x20\x50\x72\x6f\x20\x34\x39\x30\x30\x7b\x87\xcb\x7c\x1f\x8d\x82\x49\x7b"), Err(ParseError::new(ParseErrorKind::OidTooLong)));
+        assert_eq!(ObjectIdentifier::from_der(b"\x06\x40\x2b\x06\x01\x04\x01\x89\x60\x01\x01\x02\x01\x03\x15\x45\x70\x73\x6f\x6e\x20\x53\x74\x79\x6c\x75\x73\x20\x50\x72\x6f\x20\x34\x39\x30\x30\x7b\x87\xcb\x7c\x1f\x8d\x82\x49\x7b\x2b\x06\x01\x04\x01\x89\x60\x01\x01\x02\x01\x03\x15\x45\x70\x73\x6f\x6e\x20"), Err(ParseError::new(ParseErrorKind::OidTooLong)));
     }
 
     #[test]

src/parser.rs

@@ -115,6 +115,7 @@ impl fmt::Display for ParseError {
             ParseErrorKind::ExtraData => write!(f, "extra data"),
             ParseErrorKind::InvalidSetOrdering => write!(f, "SET value was ordered incorrectly"),
             ParseErrorKind::EncodedDefault => write!(f, "DEFAULT value was explicitly encoded"),
+            ParseErrorKind::OidTooLong => write!(f, "OBJECT IDENTIFIER was too large to be stored in rust-asn1's buffer"),
         }
     }
 }