Use md5 hashing for redshift_user passwords

Author: sworisbreathing

redshift/config.go

@@ -131,3 +131,9 @@ func (c *Config) Client() (*Client, error) {
 
 	return &client, nil
 }
+
+func (c *Client) Close() {
+	if c.db != nil {
+		c.db.Close()
+	}
+}

redshift/resource_redshift_user.go

@@ -1,6 +1,7 @@
 package redshift
 
 import (
+	"crypto/md5"
 	"database/sql"
 	"fmt"
 	"log"
@@ -163,6 +164,7 @@ func resourceRedshiftUserCreate(db *DBConnection, d *schema.ResourceData) error
 		{userCreateDBAttr, "CREATEDB", "NOCREATEDB"},
 	}
 
+	userName := d.Get(userNameAttr).(string)
 	createOpts := make([]string, 0, len(stringOpts)+len(intOpts)+len(boolOpts))
 	for _, opt := range stringOpts {
 		v, ok := d.GetOk(opt.hclKey)
@@ -186,7 +188,7 @@ func resourceRedshiftUserCreate(db *DBConnection, d *schema.ResourceData) error
 		if val != "" {
 			switch {
 			case opt.hclKey == userPasswordAttr:
-				createOpts = append(createOpts, fmt.Sprintf("%s '%s'", opt.sqlKey, pqQuoteLiteral(val)))
+				createOpts = append(createOpts, fmt.Sprintf("%s '%s'", opt.sqlKey, md5Password(userName, val)))
 			case opt.hclKey == userValidUntilAttr:
 				switch {
 				case v.(string) == "", strings.ToLower(v.(string)) == "infinity":
@@ -216,7 +218,6 @@ func resourceRedshiftUserCreate(db *DBConnection, d *schema.ResourceData) error
 		createOpts = append(createOpts, valStr)
 	}
 
-	userName := d.Get(userNameAttr).(string)
 	createStr := strings.Join(createOpts, " ")
 	sql := fmt.Sprintf("CREATE USER %s WITH %s", pq.QuoteIdentifier(userName), createStr)
 
@@ -594,3 +595,13 @@ func getDefaultSyslogAccess(d *schema.ResourceData) string {
 
 	return defaultUserSyslogAccess
 }
+
+// Generates an md5 password for the user.
+// Per https://docs.aws.amazon.com/redshift/latest/dg/r_CREATE_USER.html,
+// the process is:
+// 1. concatenate the password and username
+// 2. convert the concatenated string to an md5 hash in hex format
+// 3. prefix the result with 'md5' (unquoted)
+func md5Password(userName string, password string) string {
+	return fmt.Sprintf("md5%x", md5.Sum([]byte(fmt.Sprintf("%s%s", password, userName))))
+}

redshift/resource_redshift_user_test.go

@@ -3,6 +3,8 @@ package redshift
 import (
 	"database/sql"
 	"fmt"
+	"os"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -24,6 +26,7 @@ func TestAccRedshiftUser_Basic(t *testing.T) {
 
 					testAccCheckRedshiftUserExists("John-and-Jane.doe@example.com"),
 					resource.TestCheckResourceAttr("redshift_user.with_email", "name", "john-and-jane.doe@example.com"),
+					testAccCheckRedshiftUserCanLogin("John-and-Jane.doe@example.com", "Foobarbaz1"),
 
 					testAccCheckRedshiftUserExists("user_defaults"),
 					resource.TestCheckResourceAttr("redshift_user.user_with_defaults", "name", "user_defaults"),
@@ -284,3 +287,43 @@ func TestPermanentUsername(t *testing.T) {
 		t.Fatalf("permanentUsername should strip \"IAMA:\" prefix. Expected %s but was %s", expected, result)
 	}
 }
+
+func testAccCheckRedshiftUserCanLogin(user string, password string) resource.TestCheckFunc {
+	return func(s *terraform.State) error {
+		// there doesn't seem to be a good way to extract the provider configuration
+		// at runtime. However we know we've configured the provider with default settings
+		// so we can mimic the same behavior
+		port, ok := os.LookupEnv("REDSHIFT_PORT")
+		if !ok {
+			port = "5439"
+		}
+		portNum, err := strconv.Atoi(port)
+		if err != nil {
+			return fmt.Errorf("Unable to check if user can login due to bad REDSHIFT_PORT: %s", err)
+		}
+		database, ok := os.LookupEnv("REDSHIFT_DATABASE")
+		if !ok {
+			database = "redshift"
+		}
+		sslMode, ok := os.LookupEnv("REDSHIFT_SSLMODE")
+		if !ok {
+			sslMode = "require"
+		}
+		config := &Config{
+			Host:     os.Getenv("REDSHIFT_HOST"),
+			Port:     portNum,
+			Username: user,
+			Password: password,
+			Database: database,
+			SSLMode:  sslMode,
+			MaxConns: defaultProviderMaxOpenConnections,
+		}
+
+		client, err := config.Client()
+		if err != nil {
+			return fmt.Errorf("User is unable to login %s", err)
+		}
+		defer client.Close()
+		return nil
+	}
+}