From 1a7cf8ccc49f53b6cb6607ee95bda1268784e8bb Mon Sep 17 00:00:00 2001
From: Jack Christensen <jack@jackchristensen.com>
Date: Thu, 11 Apr 2013 21:39:44 -0500
Subject: [PATCH] Added connect with md5 password

---
 README.md      | 10 +++++++++-
 conn.go        | 12 ++++++++++++
 conn_test.go   | 14 +++++++++++++-
 test_setup.sql |  2 ++
 4 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 6f6cf226..e2c2b303 100644
--- a/README.md
+++ b/README.md
@@ -6,4 +6,12 @@ Experimental PostgreSQL client library for Go
 Testing
 -------
 
-To setup the test environment run the test_setup.sql script as a user that can create users and databases.
+To setup the test environment run the test_setup.sql script as a user that can
+create users and databases. To successfully run the connection tests for various
+means of authentication you must include the following in your pg_hba.conf.
+
+    local  pgx_test  pgx_none  trust
+    local  pgx_test  pgx_pw    password
+    local  pgx_test  pgx_md5   md5
+
+
diff --git a/conn.go b/conn.go
index 91abbd83..b60a783c 100644
--- a/conn.go
+++ b/conn.go
@@ -1,7 +1,9 @@
 package pqx
 
 import (
+	"crypto/md5"
 	"encoding/binary"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	"io"
@@ -189,6 +191,10 @@ func (c *conn) rxAuthenticationX(r *messageReader) (err error) {
 	case 0: // AuthenticationOk
 	case 3: // AuthenticationCleartextPassword
 		c.txPasswordMessage(c.options["password"])
+	case 5: // AuthenticationMD5Password
+		salt := r.readByteString(4)
+		digestedPassword := "md5" + hexMD5(hexMD5(c.options["password"]+c.options["user"])+salt)
+		c.txPasswordMessage(digestedPassword)
 	default:
 		err = errors.New("Received unknown authentication message")
 	}
@@ -196,6 +202,12 @@ func (c *conn) rxAuthenticationX(r *messageReader) (err error) {
 	return
 }
 
+func hexMD5(s string) string {
+	hash := md5.New()
+	io.WriteString(hash, s)
+	return hex.EncodeToString(hash.Sum(nil))
+}
+
 func (c *conn) rxParameterStatus(r *messageReader) {
 	key := r.readString()
 	value := r.readString()
diff --git a/conn_test.go b/conn_test.go
index bbbcc710..59788fcf 100644
--- a/conn_test.go
+++ b/conn_test.go
@@ -47,7 +47,7 @@ func TestConnectWithInvalidUser(t *testing.T) {
 	}
 }
 
-func TestConnectWithPassword(t *testing.T) {
+func TestConnectWithPlainTextPassword(t *testing.T) {
 	conn, err := Connect(map[string]string{"socket": "/private/tmp/.s.PGSQL.5432", "user": "pgx_pw", "password": "secret", "database": "pgx_test"})
 	if err != nil {
 		t.Fatal("Unable to establish connection: " + err.Error())
@@ -59,6 +59,18 @@ func TestConnectWithPassword(t *testing.T) {
 	}
 }
 
+func TestConnectWithMD5Password(t *testing.T) {
+	conn, err := Connect(map[string]string{"socket": "/private/tmp/.s.PGSQL.5432", "user": "pgx_md5", "password": "secret", "database": "pgx_test"})
+	if err != nil {
+		t.Fatal("Unable to establish connection: " + err.Error())
+	}
+
+	err = conn.Close()
+	if err != nil {
+		t.Fatal("Unable to close connection")
+	}
+}
+
 func TestQuery(t *testing.T) {
 	conn, err := Connect(map[string]string{"socket": "/private/tmp/.s.PGSQL.5432", "user": "pgx_none", "database": "pgx_test"})
 	if err != nil {
diff --git a/test_setup.sql b/test_setup.sql
index 15af361c..c5c73614 100644
--- a/test_setup.sql
+++ b/test_setup.sql
@@ -1,7 +1,9 @@
 drop database if exists pgx_test;
 drop user if exists pgx_none;
 drop user if exists pgx_pw;
+drop user if exists pgx_md5;
 
 create user pgx_none;
 create user pgx_pw password 'secret';
+create user pgx_md5 password 'secret';
 create database pgx_test;