talos

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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this
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// file, You can obtain one at http://mozilla.org/MPL/2.0/.
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package config
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import (
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	"errors"
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	"os"
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	"path/filepath"
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	"github.com/siderolabs/talos/pkg/machinery/constants"
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)
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// Path represents a path to a configuration file.
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type Path struct {
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	// Path is the filesystem path of the config.
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	Path string
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	// WriteAllowed is true if the path is allowed to be written.
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	WriteAllowed bool
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}
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// GetTalosDirectory returns path to Talos directory (~/.talos).
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func GetTalosDirectory() (string, error) {
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	home, err := os.UserHomeDir()
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	if err != nil {
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		return "", err
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	}
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	return filepath.Join(home, constants.TalosDir), nil
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}
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// GetDefaultPaths returns the list of config file paths in order of priority.
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func GetDefaultPaths() ([]Path, error) {
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	talosDir, err := GetTalosDirectory()
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	if err != nil {
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		return nil, err
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	}
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	result := make([]Path, 0, 3)
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	if path, ok := os.LookupEnv(constants.TalosConfigEnvVar); ok {
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		result = append(result, Path{
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			Path:         path,
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			WriteAllowed: true,
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		})
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	}
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	result = append(
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		result,
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		Path{
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			Path:         filepath.Join(talosDir, constants.TalosconfigFilename),
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			WriteAllowed: true,
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		},
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		Path{
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			Path:         filepath.Join(constants.ServiceAccountMountPath, constants.TalosconfigFilename),
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			WriteAllowed: false,
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		},
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	)
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	return result, nil
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}
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// firstValidPath iterates over the default paths and returns the first one that exists and readable.
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// If no path is found, it will ensure that the first path that allows writes is created and returned.
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// If no path is found that is writable, an error is returned.
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func firstValidPath() (Path, error) {
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	paths, err := GetDefaultPaths()
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	if err != nil {
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		return Path{}, err
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	}
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	var firstWriteAllowed Path
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	for _, path := range paths {
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		_, err = os.Stat(path.Path)
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		if err == nil {
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			return path, nil
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		}
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		if firstWriteAllowed.Path == "" && path.WriteAllowed {
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			firstWriteAllowed = path
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		}
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	}
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	if firstWriteAllowed.Path == "" {
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		return Path{}, errors.New("no valid config paths found")
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	}
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	err = ensure(firstWriteAllowed.Path)
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	if err != nil {
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		return Path{}, err
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	}
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	return firstWriteAllowed, nil
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}
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