GoToSocial/vendor/github.com/jackc/pgpassfile/pgpass.go

111 lines
2.6 KiB
Go

// Package pgpassfile is a parser PostgreSQL .pgpass files.
package pgpassfile
import (
"bufio"
"io"
"os"
"regexp"
"strings"
)
// Entry represents a line in a PG passfile.
type Entry struct {
Hostname string
Port string
Database string
Username string
Password string
}
// Passfile is the in memory data structure representing a PG passfile.
type Passfile struct {
Entries []*Entry
}
// ReadPassfile reads the file at path and parses it into a Passfile.
func ReadPassfile(path string) (*Passfile, error) {
f, err := os.Open(path)
if err != nil {
return nil, err
}
defer f.Close()
return ParsePassfile(f)
}
// ParsePassfile reads r and parses it into a Passfile.
func ParsePassfile(r io.Reader) (*Passfile, error) {
passfile := &Passfile{}
scanner := bufio.NewScanner(r)
for scanner.Scan() {
entry := parseLine(scanner.Text())
if entry != nil {
passfile.Entries = append(passfile.Entries, entry)
}
}
return passfile, scanner.Err()
}
// Match (not colons or escaped colon or escaped backslash)+. Essentially gives a split on unescaped
// colon.
var colonSplitterRegexp = regexp.MustCompile("(([^:]|(\\:)))+")
// var colonSplitterRegexp = regexp.MustCompile("((?:[^:]|(?:\\:)|(?:\\\\))+)")
// parseLine parses a line into an *Entry. It returns nil on comment lines or any other unparsable
// line.
func parseLine(line string) *Entry {
const (
tmpBackslash = "\r"
tmpColon = "\n"
)
line = strings.TrimSpace(line)
if strings.HasPrefix(line, "#") {
return nil
}
line = strings.Replace(line, `\\`, tmpBackslash, -1)
line = strings.Replace(line, `\:`, tmpColon, -1)
parts := strings.Split(line, ":")
if len(parts) != 5 {
return nil
}
// Unescape escaped colons and backslashes
for i := range parts {
parts[i] = strings.Replace(parts[i], tmpBackslash, `\`, -1)
parts[i] = strings.Replace(parts[i], tmpColon, `:`, -1)
}
return &Entry{
Hostname: parts[0],
Port: parts[1],
Database: parts[2],
Username: parts[3],
Password: parts[4],
}
}
// FindPassword finds the password for the provided hostname, port, database, and username. For a
// Unix domain socket hostname must be set to "localhost". An empty string will be returned if no
// match is found.
//
// See https://www.postgresql.org/docs/current/libpq-pgpass.html for more password file information.
func (pf *Passfile) FindPassword(hostname, port, database, username string) (password string) {
for _, e := range pf.Entries {
if (e.Hostname == "*" || e.Hostname == hostname) &&
(e.Port == "*" || e.Port == port) &&
(e.Database == "*" || e.Database == database) &&
(e.Username == "*" || e.Username == username) {
return e.Password
}
}
return ""
}