From 8fcd43d8f2b15b62f819a1ea41dcd91ac3194f0b Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sun, 4 Apr 2021 08:46:00 +0200
Subject: [PATCH] config: forbid host names which conflict with special groups

---
 cmd/safcm/config/hosts.go                     |  19 ++++
 cmd/safcm/config/hosts_test.go                | 103 ++++++++++++++++++
 .../testdata/host-invalid-all/hosts.yaml      |   1 +
 .../testdata/host-invalid-detected/hosts.yaml |   1 +
 .../testdata/host-invalid-special/hosts.yaml  |   1 +
 5 files changed, 125 insertions(+)
 create mode 100644 cmd/safcm/config/hosts_test.go
 create mode 100644 cmd/safcm/testdata/host-invalid-all/hosts.yaml
 create mode 100644 cmd/safcm/testdata/host-invalid-detected/hosts.yaml
 create mode 100644 cmd/safcm/testdata/host-invalid-special/hosts.yaml

diff --git a/cmd/safcm/config/hosts.go b/cmd/safcm/config/hosts.go
index 1199687..b3c4a24 100644
--- a/cmd/safcm/config/hosts.go
+++ b/cmd/safcm/config/hosts.go
@@ -20,6 +20,7 @@ package config
 import (
 	"fmt"
 	"os"
+	"strings"
 
 	"gopkg.in/yaml.v2"
 )
@@ -50,6 +51,24 @@ func LoadHosts() (*Hosts, error) {
 
 	hostMap := make(map[string]*Host)
 	for _, x := range hostList {
+		errPrefix := fmt.Sprintf("%s: host %q:", path, x.Name)
+		if x.Name == GroupAll {
+			return nil, fmt.Errorf(
+				"%s conflict with pre-defined group %q",
+				errPrefix, x.Name)
+		}
+		if strings.HasPrefix(x.Name, GroupDetectedPrefix) {
+			return nil, fmt.Errorf(
+				"%s name must not start with %q "+
+					"(reserved for detected groups)",
+				errPrefix, GroupDetectedPrefix)
+		}
+		if strings.Contains(x.Name, GroupSpecialSeparator) {
+			return nil, fmt.Errorf(
+				"%s name must not contain %q",
+				errPrefix, GroupSpecialSeparator)
+		}
+
 		hostMap[x.Name] = x
 	}
 
diff --git a/cmd/safcm/config/hosts_test.go b/cmd/safcm/config/hosts_test.go
new file mode 100644
index 0000000..49f4d56
--- /dev/null
+++ b/cmd/safcm/config/hosts_test.go
@@ -0,0 +1,103 @@
+// Copyright (C) 2021  Simon Ruderich
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"reflect"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestLoadHosts(t *testing.T) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Chdir(cwd)
+
+	sliceToHosts := func(hosts []*Host) *Hosts {
+		res := &Hosts{
+			List: hosts,
+			Map:  make(map[string]*Host),
+		}
+		for _, x := range hosts {
+			res.Map[x.Name] = x
+		}
+		return res
+	}
+
+	tests := []struct {
+		path   string
+		exp    *Hosts
+		expErr error
+	}{
+
+		{
+			"../testdata/project",
+			sliceToHosts([]*Host{
+				{
+					Name: "host1.example.org",
+				},
+				{
+					Name: "host2",
+				},
+				{
+					Name: "host3.example.net",
+				},
+			}),
+			nil,
+		},
+
+		{
+			"../testdata/host-invalid-all",
+			nil,
+			fmt.Errorf("hosts.yaml: host \"all\": conflict with pre-defined group \"all\""),
+		},
+		{
+			"../testdata/host-invalid-detected",
+			nil,
+			fmt.Errorf("hosts.yaml: host \"detected\": name must not start with \"detected\" (reserved for detected groups)"),
+		},
+		{
+			"../testdata/host-invalid-special",
+			nil,
+			fmt.Errorf("hosts.yaml: host \"special:host\": name must not contain \":\""),
+		},
+	}
+
+	for _, tc := range tests {
+		err := os.Chdir(filepath.Join(cwd, tc.path))
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		res, err := LoadHosts()
+
+		if !reflect.DeepEqual(tc.exp, res) {
+			t.Errorf("%s: res: %s", tc.path,
+				cmp.Diff(tc.exp, res))
+		}
+		// Ugly but the simplest way to compare errors (including nil)
+		if fmt.Sprintf("%s", err) != fmt.Sprintf("%s", tc.expErr) {
+			t.Errorf("%s: err = %#v, want %#v",
+				tc.path, err, tc.expErr)
+		}
+	}
+}
diff --git a/cmd/safcm/testdata/host-invalid-all/hosts.yaml b/cmd/safcm/testdata/host-invalid-all/hosts.yaml
new file mode 100644
index 0000000..287c1c0
--- /dev/null
+++ b/cmd/safcm/testdata/host-invalid-all/hosts.yaml
@@ -0,0 +1 @@
+- name: all
diff --git a/cmd/safcm/testdata/host-invalid-detected/hosts.yaml b/cmd/safcm/testdata/host-invalid-detected/hosts.yaml
new file mode 100644
index 0000000..bf244e4
--- /dev/null
+++ b/cmd/safcm/testdata/host-invalid-detected/hosts.yaml
@@ -0,0 +1 @@
+- name: detected
diff --git a/cmd/safcm/testdata/host-invalid-special/hosts.yaml b/cmd/safcm/testdata/host-invalid-special/hosts.yaml
new file mode 100644
index 0000000..84a2e6b
--- /dev/null
+++ b/cmd/safcm/testdata/host-invalid-special/hosts.yaml
@@ -0,0 +1 @@
+- name: special:host
-- 
2.45.2