fix: protect agent canary database credentials

cmd/agent-canary/main.go

@@ -6,12 +6,16 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"path/filepath"
+	"strings"
 	"time"
 
 	"git.cin.su/m/Assistant/adapters/postgres"
+	secretcontracts "git.cin.su/m/Assistant/contracts/secrets"
 	"git.cin.su/m/Assistant/contracts/work"
 	"git.cin.su/m/Assistant/modules/work/application"
 	"git.cin.su/m/Assistant/modules/work/ports"
+	platformsecrets "git.cin.su/m/Assistant/platform/secrets"
 )
 
 type memoryStore struct{ writes int }
@@ -37,7 +41,12 @@ func main() {
 	var store ports.ExecutionStore = &memoryStore{}
 	var closeStore func()
 	if *postgresMode {
-		repository, err := postgres.OpenWork(context.Background(), postgres.ContinuityConfig{Host: os.Getenv("POSTGRES_HOST"), Port: os.Getenv("POSTGRES_PORT"), Database: os.Getenv("POSTGRES_DATABASE"), User: os.Getenv("WORK_POSTGRES_USER"), Password: os.Getenv("WORK_POSTGRES_PASSWORD")})
+		password, err := resolveDatabasePassword()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+		repository, err := postgres.OpenWork(context.Background(), postgres.ContinuityConfig{Host: os.Getenv("POSTGRES_HOST"), Port: os.Getenv("POSTGRES_PORT"), Database: os.Getenv("POSTGRES_DATABASE"), User: os.Getenv("WORK_POSTGRES_USER"), Password: password})
 		if err != nil {
 			fmt.Fprintln(os.Stderr, err)
 			os.Exit(1)
@@ -67,3 +76,27 @@ func main() {
 		os.Exit(1)
 	}
 }
+
+func resolveDatabasePassword() (string, error) {
+	if _, ok := os.LookupEnv("WORK_POSTGRES_PASSWORD"); ok {
+		return "", fmt.Errorf("WORK_POSTGRES_PASSWORD direct environment secret is forbidden")
+	}
+	path, ref := os.Getenv("WORK_POSTGRES_PASSWORD_FILE"), os.Getenv("WORK_POSTGRES_CREDENTIAL_REF")
+	if path == "" || ref == "" {
+		return "", fmt.Errorf("WORK_POSTGRES_PASSWORD_FILE and WORK_POSTGRES_CREDENTIAL_REF are required")
+	}
+	root := os.Getenv("SECRET_BACKEND_ROOT")
+	if root == "" {
+		root = "/run/secrets"
+	}
+	cleanRoot := filepath.Clean(root)
+	cleanPath := filepath.Clean(path)
+	if cleanPath != cleanRoot && !strings.HasPrefix(cleanPath, cleanRoot+string(os.PathSeparator)) {
+		return "", fmt.Errorf("database password file escapes protected secret root")
+	}
+	resolver, err := platformsecrets.NewFileResolver(cleanRoot)
+	if err != nil {
+		return "", err
+	}
+	return resolver.ResolveFile(secretcontracts.SecretFileRef{CredentialRef: secretcontracts.CredentialRef(ref), Purpose: secretcontracts.SecretPurposeDatabasePassword, Consumer: secretcontracts.RuntimeConsumerWorkWorker, Path: cleanPath})
+}

cmd/agent-canary/main_test.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"path/filepath"
+	"testing"
+)
+
+func TestResolveDatabasePasswordRejectsDirectEnvironmentSecret(t *testing.T) {
+	t.Setenv("WORK_POSTGRES_PASSWORD", "literal-secret")
+	if _, err := resolveDatabasePassword(); err == nil {
+		t.Fatal("direct database password environment variable was accepted")
+	}
+}
+
+func TestResolveDatabasePasswordRejectsPathOutsideProtectedRoot(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("SECRET_BACKEND_ROOT", root)
+	t.Setenv("WORK_POSTGRES_PASSWORD_FILE", filepath.Join(root, "..", "outside"))
+	t.Setenv("WORK_POSTGRES_CREDENTIAL_REF", "credential://domovoy/work/db-password/v1")
+	if _, err := resolveDatabasePassword(); err == nil {
+		t.Fatal("database password path outside protected root was accepted")
+	}
+}