diff options
author | Justus Winter <justus@sequoia-pgp.org> | 2020-01-02 17:12:03 +0100 |
---|---|---|
committer | Justus Winter <justus@sequoia-pgp.org> | 2020-01-02 17:52:40 +0100 |
commit | 60e1d354f8bde0db5f5808e395c082cfce726d0d (patch) | |
tree | 5cc79fd9d41a05c8fe8d8c3461a41871e3aa3deb /openpgp/src | |
parent | eab85ce1df7f67f0b92f33db1c62d997e5829165 (diff) |
openpgp: Fix roundtripping of KeyFlags, add test.
- In particular, preserve any padding.
Diffstat (limited to 'openpgp/src')
-rw-r--r-- | openpgp/src/types/key_flags.rs | 41 | ||||
-rw-r--r-- | openpgp/src/types/mod.rs | 12 |
2 files changed, 50 insertions, 3 deletions
diff --git a/openpgp/src/types/key_flags.rs b/openpgp/src/types/key_flags.rs index 815018dd..9d461565 100644 --- a/openpgp/src/types/key_flags.rs +++ b/openpgp/src/types/key_flags.rs @@ -14,6 +14,8 @@ pub struct KeyFlags{ is_split_key: bool, is_group_key: bool, unknown: Box<[u8]>, + /// Original length, including trailing zeros. + pad_to: usize, } impl Default for KeyFlags { @@ -50,6 +52,9 @@ impl fmt::Debug for KeyFlags { f.write_str( &crate::fmt::hex::encode_pretty(&self.unknown))?; } + if self.pad_to > self.unknown.len() { + write!(f, "+padding({} bytes)", self.pad_to - self.unknown.len())?; + } Ok(()) } @@ -66,7 +71,9 @@ impl Eq for KeyFlags {} impl PartialOrd for KeyFlags { fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> { let mut a_bits = self.to_vec(); + crate::types::bitfield_remove_padding(&mut a_bits); let mut b_bits = other.to_vec(); + crate::types::bitfield_remove_padding(&mut b_bits); let len = cmp::max(a_bits.len(), b_bits.len()); while a_bits.len() < len { a_bits.push(0); } @@ -126,6 +133,8 @@ impl KeyFlags { /// Creates a new instance from `bits`. pub fn new<B: AsRef<[u8]>>(bits: B) -> Self { let bits = bits.as_ref(); + let mut pad_to = 0; + let for_certification = bits.get(0) .map(|x| x & KEY_FLAG_CERTIFY != 0).unwrap_or(false); let for_signing = bits.get(0) @@ -151,14 +160,14 @@ impl KeyFlags { KEY_FLAG_GROUP_KEY | KEY_FLAG_SPLIT_KEY ) ^ 0xff; - while cpy.last().cloned() == Some(0) { cpy.pop(); } + pad_to = crate::types::bitfield_remove_padding(&mut cpy); cpy.into_boxed_slice() }; KeyFlags{ for_certification, for_signing, for_transport_encryption, for_storage_encryption, for_authentication, is_split_key, - is_group_key, unknown: unk + is_group_key, unknown: unk, pad_to, } } @@ -181,7 +190,19 @@ impl KeyFlags { if self.for_storage_encryption { ret[0] |= KEY_FLAG_ENCRYPT_AT_REST; } if self.for_authentication { ret[0] |= KEY_FLAG_AUTHENTICATE; } if self.is_split_key { ret[0] |= KEY_FLAG_SPLIT_KEY; } - if self.is_group_key { ret[0] |= KEY_FLAG_GROUP_KEY } + if self.is_group_key { ret[0] |= KEY_FLAG_GROUP_KEY; } + + // Corner case: empty flag field. We initialized ret to + // vec![0] for easy setting of flags. See if any of the above + // was set. + if ret.len() == 1 && ret[0] == 0 { + // Nope. Trim this byte. + ret.pop(); + } + + for _ in ret.len()..self.pad_to { + ret.push(0); + } ret } @@ -319,4 +340,18 @@ mod tests { assert!(!(enc < sig)); assert!(!(enc > sig)); } + + quickcheck! { + fn roundtrip(raw: Vec<u8>) -> bool { + let val = KeyFlags::new(&raw); + assert_eq!(raw, val.to_vec()); + + // Check that equality ignores padding. + let mut val_without_padding = val.clone(); + val_without_padding.pad_to = val.unknown.len(); + assert_eq!(val, val_without_padding); + + true + } + } } diff --git a/openpgp/src/types/mod.rs b/openpgp/src/types/mod.rs index 01ada8f7..ac6811d5 100644 --- a/openpgp/src/types/mod.rs +++ b/openpgp/src/types/mod.rs @@ -21,6 +21,18 @@ pub use self::server_preferences::KeyServerPreferences; mod timestamp; pub use timestamp::{Timestamp, Duration}; +/// Removes padding bytes from bitfields. +/// +/// Returns the size of the original bitfield, i.e. the number of +/// bytes the output has to be padded to when serialized. +pub(crate) fn bitfield_remove_padding(b: &mut Vec<u8>) -> usize { + let pad_to = b.len(); + while b.last() == Some(&0) { + b.pop(); + } + pad_to +} + /// The OpenPGP public key algorithms as defined in [Section 9.1 of /// RFC 4880], and [Section 5 of RFC 6637]. /// |