mediamtx/internal/conf/credential.go
2024-02-20 19:35:35 +01:00

109 lines
2.8 KiB
Go

package conf
import (
"crypto/sha256"
"encoding/base64"
"encoding/json"
"fmt"
"regexp"
"strings"
"github.com/matthewhartstonge/argon2"
)
var (
rePlainCredential = regexp.MustCompile(`^[a-zA-Z0-9!\$\(\)\*\+\.;<=>\[\]\^_\-\{\}@#&]+$`)
reBase64 = regexp.MustCompile(`^sha256:[a-zA-Z0-9\+/=]+$`)
)
const plainCredentialSupportedChars = "A-Z,0-9,!,$,(,),*,+,.,;,<,=,>,[,],^,_,-,\",\",@,#,&"
func sha256Base64(in string) string {
h := sha256.New()
h.Write([]byte(in))
return base64.StdEncoding.EncodeToString(h.Sum(nil))
}
// Credential is a parameter that is used as username or password.
type Credential string
// MarshalJSON implements json.Marshaler.
func (d Credential) MarshalJSON() ([]byte, error) {
return json.Marshal(string(d))
}
// UnmarshalJSON implements json.Unmarshaler.
func (d *Credential) UnmarshalJSON(b []byte) error {
var in string
if err := json.Unmarshal(b, &in); err != nil {
return err
}
*d = Credential(in)
return d.validate()
}
// UnmarshalEnv implements env.Unmarshaler.
func (d *Credential) UnmarshalEnv(_ string, v string) error {
return d.UnmarshalJSON([]byte(`"` + v + `"`))
}
// IsSha256 returns true if the credential is a sha256 hash.
func (d Credential) IsSha256() bool {
return strings.HasPrefix(string(d), "sha256:")
}
// IsArgon2 returns true if the credential is an argon2 hash.
func (d Credential) IsArgon2() bool {
return strings.HasPrefix(string(d), "argon2:")
}
// IsHashed returns true if the credential is a sha256 or argon2 hash.
func (d Credential) IsHashed() bool {
return d.IsSha256() || d.IsArgon2()
}
// Check returns true if the given value matches the credential.
func (d Credential) Check(guess string) bool {
if d.IsSha256() {
return string(d)[len("sha256:"):] == sha256Base64(guess)
}
if d.IsArgon2() {
// TODO: remove matthewhartstonge/argon2 when this PR gets merged into mainline Go:
// https://go-review.googlesource.com/c/crypto/+/502515
ok, err := argon2.VerifyEncoded([]byte(guess), []byte(string(d)[len("argon2:"):]))
return ok && err == nil
}
if d != "" {
return string(d) == guess
}
return true
}
func (d Credential) validate() error {
if d != "" {
switch {
case d.IsSha256():
if !reBase64.MatchString(string(d)) {
return fmt.Errorf("credential contains unsupported characters, sha256 hash must be base64 encoded")
}
case d.IsArgon2():
// TODO: remove matthewhartstonge/argon2 when this PR gets merged into mainline Go:
// https://go-review.googlesource.com/c/crypto/+/502515
_, err := argon2.Decode([]byte(string(d)[len("argon2:"):]))
if err != nil {
return fmt.Errorf("invalid argon2 hash: %w", err)
}
default:
if !rePlainCredential.MatchString(string(d)) {
return fmt.Errorf("credential contains unsupported characters. Supported are: %s", plainCredentialSupportedChars)
}
}
}
return nil
}