openpgp: Add support for the AEAD encrypted data packet.

  - This adds a new packet type, and enough infrastructure to decrypt
    messages encrypted using AEAD.

3 files changed, 47 insertions, 3 deletions

diff --git a/openpgp/src/message/grammar.lalrpop b/openpgp/src/message/grammar.lalrpop
index 1fe2c2c7..d5c0ea36 100644
--- a/openpgp/src/message/grammar.lalrpop
+++ b/openpgp/src/message/grammar.lalrpop
@@ -21,10 +21,19 @@ SeipPart: () = {
     SEIP OPAQUE_CONTENT POP,
 }
 
-// An encrypted part is 0 or more ESKs followed by a SEIP packet.
+AedPart: () = {
+    AED Message POP,
+}
+
+// An encrypted part is 0 or more ESKs followed by an encryption container.
 EncryptedPart: () = {
+    EncryptionContainer,
+    ESKS EncryptionContainer,
+};
+
+EncryptionContainer: () = {
     SeipPart,
-    ESKS SeipPart,
+    AedPart,
 };
 
 ESKS: () = {
@@ -61,6 +70,7 @@ extern {
         PKESK => lexer::Token::PKESK,
         SEIP => lexer::Token::SEIP,
         MDC => lexer::Token::MDC,
+        AED => lexer::Token::AED,
         OPS => lexer::Token::OPS,
         SIG => lexer::Token::SIG,
         POP => lexer::Token::Pop,
diff --git a/openpgp/src/message/lexer.rs b/openpgp/src/message/lexer.rs
index 778735d3..fc561d62 100644
--- a/openpgp/src/message/lexer.rs
+++ b/openpgp/src/message/lexer.rs
@@ -23,6 +23,8 @@ pub enum Token {
     SEIP,
     /// An MDC packet.
     MDC,
+    /// An AED packet.
+    AED,
 
     /// A OnePassSig packet.
     OPS,
diff --git a/openpgp/src/message/mod.rs b/openpgp/src/message/mod.rs
index 557c94e0..dfa332a9 100644
--- a/openpgp/src/message/mod.rs
+++ b/openpgp/src/message/mod.rs
@@ -209,6 +209,7 @@ impl MessageValidator {
             Tag::PKESK => Token::PKESK,
             Tag::SEIP => Token::SEIP,
             Tag::MDC => Token::MDC,
+            Tag::AED => Token::AED,
             Tag::OnePassSig => Token::OPS,
             Tag::Signature => Token::SIG,
             _ => {
@@ -307,7 +308,8 @@ impl Message {
             v.push(packet.tag(), path.len() as isize - 1);
 
             match packet {
-                Packet::CompressedData(_) | Packet::SEIP(_) => {
+                Packet::CompressedData(_) | Packet::SEIP(_) | Packet::AED(_) =>
+                {
                     // If a container's content is not unpacked, then
                     // we treat the content as an opaque message.
 
@@ -467,6 +469,36 @@ mod tests {
             },
 
             TestVector {
+                s: &[AED, Literal, Pop],
+                result: true,
+            },
+            TestVector {
+                s: &[CompressedData, AED, Literal, Pop, Pop],
+                result: true,
+            },
+            TestVector {
+                s: &[CompressedData, AED, CompressedData, Literal,
+                     Pop, Pop, Pop],
+                result: true,
+            },
+            TestVector {
+                s: &[AED, Pop],
+                result: false,
+            },
+            TestVector {
+                s: &[SKESK, AED, Literal, Pop],
+                result: true,
+            },
+            TestVector {
+                s: &[PKESK, AED, Literal, Pop],
+                result: true,
+            },
+            TestVector {
+                s: &[SKESK, SKESK, AED, Literal, Pop],
+                result: true,
+            },
+
+            TestVector {
                 s: &[OPS, Literal, SIG],
                 result: true,
             },