authelia/internal/totp/totp.go

80 lines
2.0 KiB
Go

package totp
import (
"time"
"github.com/pquerna/otp"
"github.com/pquerna/otp/totp"
"github.com/authelia/authelia/v4/internal/configuration/schema"
"github.com/authelia/authelia/v4/internal/model"
)
// NewTimeBasedProvider creates a new totp.TimeBased which implements the totp.Provider.
func NewTimeBasedProvider(config schema.TOTPConfiguration) (provider *TimeBased) {
provider = &TimeBased{
config: &config,
}
if config.Skew != nil {
provider.skew = *config.Skew
} else {
provider.skew = 1
}
return provider
}
// TimeBased totp.Provider for production use.
type TimeBased struct {
config *schema.TOTPConfiguration
skew uint
}
// GenerateCustom generates a TOTP with custom options.
func (p TimeBased) GenerateCustom(username, algorithm string, digits, period, secretSize uint) (config *model.TOTPConfiguration, err error) {
var key *otp.Key
opts := totp.GenerateOpts{
Issuer: p.config.Issuer,
AccountName: username,
Period: period,
SecretSize: secretSize,
Digits: otp.Digits(digits),
Algorithm: otpStringToAlgo(algorithm),
}
if key, err = totp.Generate(opts); err != nil {
return nil, err
}
config = &model.TOTPConfiguration{
CreatedAt: time.Now(),
Username: username,
Issuer: p.config.Issuer,
Algorithm: algorithm,
Digits: digits,
Secret: []byte(key.Secret()),
Period: period,
}
return config, nil
}
// Generate generates a TOTP with default options.
func (p TimeBased) Generate(username string) (config *model.TOTPConfiguration, err error) {
return p.GenerateCustom(username, p.config.Algorithm, p.config.Digits, p.config.Period, 32)
}
// Validate the token against the given configuration.
func (p TimeBased) Validate(token string, config *model.TOTPConfiguration) (valid bool, err error) {
opts := totp.ValidateOpts{
Period: config.Period,
Skew: p.skew,
Digits: otp.Digits(config.Digits),
Algorithm: otpStringToAlgo(config.Algorithm),
}
return totp.ValidateCustom(token, string(config.Secret), time.Now().UTC(), opts)
}