restic/internal/backend/sftp/config.go

95 lines
2.6 KiB
Go

package sftp
import (
"net/url"
"path"
"strings"
"github.com/restic/restic/internal/errors"
"github.com/restic/restic/internal/options"
)
// Config collects all information required to connect to an sftp server.
type Config struct {
User, Host, Port, Path string
Layout string `option:"layout" help:"use this backend directory layout (default: auto-detect)"`
Command string `option:"command" help:"specify command to create sftp connection"`
Connections uint `option:"connections" help:"set a limit for the number of concurrent connections (default: 5)"`
}
// NewConfig returns a new config with default options applied.
func NewConfig() Config {
return Config{
Connections: 5,
}
}
func init() {
options.Register("sftp", Config{})
}
// ParseConfig parses the string s and extracts the sftp config. The
// supported configuration formats are sftp://user@host[:port]/directory
// and sftp:user@host:directory. The directory will be path Cleaned and can
// be an absolute path if it starts with a '/' (e.g.
// sftp://user@host//absolute and sftp:user@host:/absolute).
func ParseConfig(s string) (interface{}, error) {
var user, host, port, dir string
switch {
case strings.HasPrefix(s, "sftp://"):
// parse the "sftp://user@host/path" url format
url, err := url.Parse(s)
if err != nil {
return nil, errors.Wrap(err, "url.Parse")
}
if url.User != nil {
user = url.User.Username()
}
host = url.Hostname()
port = url.Port()
dir = url.Path
if dir == "" {
return nil, errors.Errorf("invalid backend %q, no directory specified", s)
}
dir = dir[1:]
case strings.HasPrefix(s, "sftp:"):
// parse the sftp:user@host:path format, which means we'll get
// "user@host:path" in s
s = s[5:]
// split user@host and path at the colon
data := strings.SplitN(s, ":", 2)
if len(data) < 2 {
return nil, errors.New("sftp: invalid format, hostname or path not found")
}
host = data[0]
dir = data[1]
// split user and host at the "@"
data = strings.SplitN(host, "@", 3)
if len(data) == 3 {
user = data[0] + "@" + data[1]
host = data[2]
} else if len(data) == 2 {
user = data[0]
host = data[1]
}
default:
return nil, errors.New(`invalid format, does not start with "sftp:"`)
}
p := path.Clean(dir)
if strings.HasPrefix(p, "~") {
return nil, errors.Fatal("sftp path starts with the tilde (~) character, that fails for most sftp servers.\nUse a relative directory, most servers interpret this as relative to the user's home directory.")
}
cfg := NewConfig()
cfg.User = user
cfg.Host = host
cfg.Port = port
cfg.Path = p
return cfg, nil
}