Add constructors for PasswordMessage

mason-postgres-protocol/Cargo.toml

@@ -12,6 +12,7 @@ bytes = "0.4.12"
 memchr = "2.2.0"
 md-5 = "0.8.0"
 itoa = "0.4.4"
+hex = "0.3.2"
 
 [dev-dependencies]
 matches = "0.1.8"

mason-postgres-protocol/src/lib.rs

@@ -5,17 +5,17 @@ mod backend_key_data;
 mod decode;
 mod encode;
 mod message;
+mod password_message;
 mod ready_for_query;
 mod response;
 mod startup_message;
-mod password_message;
 
 pub use self::{
     decode::Decode,
     encode::Encode,
     message::Message,
+    password_message::PasswordMessage,
     ready_for_query::{ReadyForQuery, TransactionStatus},
     response::{Response, ResponseBuilder, Severity},
     startup_message::StartupMessage,
-    password_message::PasswordMessage,
 };

mason-postgres-protocol/src/password_message.rs

@@ -1,20 +1,30 @@
+use crate::{Decode, Encode};
 use bytes::Bytes;
+use md5::{Digest, Md5};
 use std::io;
-use crate::{Encode,  Decode};
 
 pub struct PasswordMessage {
     password: Bytes,
 }
 
 impl PasswordMessage {
-    pub fn cleartext(s: impl AsRef<str>) -> Self {
-        // TODO
-        unimplemented!()
+    /// Create a `PasswordMessage` with an unecrypted password.
+    pub fn cleartext(password: impl AsRef<str>) -> Self {
+        Self { password: Bytes::from(password.as_ref()) }
     }
 
-    pub fn md5(s: impl AsRef<str>) -> Self {
-        // TODO
-        unimplemented!()
+    /// Create a `PasswordMessage` by hasing the password, user, and salt together using MD5.
+    pub fn md5(password: impl AsRef<str>, user: impl AsRef<str>, salt: &[u8; 4]) -> Self {
+        let credentials =
+            hex::encode(Md5::new().chain(password.as_ref()).chain(user.as_ref()).result());
+
+        let salted = hex::encode(Md5::new().chain(credentials).chain(salt).result());
+
+        let mut password = Vec::with_capacity(3 + salted.len());
+        password.copy_from_slice(b"md5");
+        password.copy_from_slice(salted.as_bytes());
+
+        Self { password: Bytes::from(password) }
     }
 
     /// The password (encrypted, if requested).
@@ -24,8 +34,10 @@ impl PasswordMessage {
 }
 
 impl Decode for PasswordMessage {
-    fn decode(src: Bytes) -> io::Result<Self> where
-        Self: Sized {
+    fn decode(src: Bytes) -> io::Result<Self>
+    where
+        Self: Sized,
+    {
         // There is only one field, the password, and it's not like we can
         // decrypt it if it was encrypted
         Ok(PasswordMessage { password: src })
@@ -39,7 +51,7 @@ impl Encode for PasswordMessage {
 
     fn encode(&self, buf: &mut Vec<u8>) -> io::Result<()> {
         buf.push(b'p');
-        buf.copy_from_slice((self.password.len() + 4).to_be_bytes());
+        buf.copy_from_slice(&(self.password.len() + 4).to_be_bytes());
         buf.copy_from_slice(&self.password);
 
         Ok(())

mason-postgres-protocol/src/startup_message.rs

@@ -1,6 +1,6 @@
+use crate::{Decode, Encode};
 use bytes::Bytes;
 use std::io;
-use crate::{Encode,  Decode};
 
 pub struct StartupMessage {
     version: u32,