diff options
| -rw-r--r-- | lib/srp.go | 51 | ||||
| -rw-r--r-- | lib/srp_test.go | 66 |
2 files changed, 117 insertions, 0 deletions
@@ -134,6 +134,42 @@ func NewSRPUser(n, g, k, ident, pass string) (*SRPUser, error) { return user, nil } +func (u *SRPUser) EphemeralKeyGen() { + for { + u.b = big.NewInt(RandomInt(1, 10000000)) + if u.b.Cmp(big.NewInt(0)) == 1 { + break + } + } +} + +func (u *SRPUser) EphemeralKeyPub() (*big.Int, error) { + if u.k == nil || u.k.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"k is not initialized"} + } + if u.v == nil || u.v.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"v is not initialized"} + } + if u.g == nil || u.g.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"g is not initialized"} + } + if u.b == nil || u.b.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"b is not initialized"} + } + + kv := new(big.Int) + kv.Mul(u.k, u.v) + + gb := new(big.Int) + gb.Exp(u.g, u.b, u.n) + + // pub is 'B' + pub := new(big.Int) + pub.Add(kv, gb) + + return pub, nil +} + func NewSRPClientSession(n, g, k, ident string) (*SRPClientSession, error) { var ok bool @@ -161,3 +197,18 @@ func NewSRPClientSession(n, g, k, ident string) (*SRPClientSession, error) { return session, nil } + +func (s *SRPClientSession) EphemeralKeyPub() (*big.Int, error) { + if s.g == nil || s.g.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"g is not initialized"} + } + if s.a == nil || s.a.Cmp(big.NewInt(0)) != 1 { + return nil, CPError{"a is not initialized"} + } + + // pub is 'A' + pub := new(big.Int) + pub.Exp(s.g, s.a, s.n) + + return pub, nil +} diff --git a/lib/srp_test.go b/lib/srp_test.go index a31e658..3e3c8d6 100644 --- a/lib/srp_test.go +++ b/lib/srp_test.go @@ -68,6 +68,42 @@ func TestNewSRPUser(t *testing.T) { } } +func TestSRPUserEphemeralKey(t *testing.T) { + n := StripSpaceChars( + `ffffffffffffffffc90fdaa22168c234c4c6628b80dc1cd129024 + e088a67cc74020bbea63b139b22514a08798e3404ddef9519b3cd + 3a431b302b0a6df25f14374fe1356d6d51c245e485b576625e7ec + 6f44c42e9a637ed6b0bff5cb6f406b7edee386bfb5a899fa5ae9f + 24117c4b1fe649286651ece45b3dc2007cb8a163bf0598da48361 + c55d39a69163fa8fd24cf5f83655d23dca3ad961c62f356208552 + bb9ed529077096966d670c354e4abc9804f1746c08ca237327fff + fffffffffffff`) + g := "2" + k := "3" + ident := "s@ricketyspace.net" + pass := "d59d6c93af0f37f272d924979" + user, err := NewSRPUser(n, g, k, ident, pass) + if err != nil { + t.Errorf("Error: %v\n", err) + return + } + + user.EphemeralKeyGen() + if user.b.Cmp(big.NewInt(0)) != 1 { + t.Errorf("Error: b is <= 0") + return + } + pub, err := user.EphemeralKeyPub() + if err != nil { + t.Errorf("Error: %v\n", err) + return + } + if pub.Cmp(big.NewInt(0)) != 1 { + t.Errorf("Error: pub is <= 0") + return + } +} + func TestNewSRPClientSession(t *testing.T) { n := StripSpaceChars( `ffffffffffffffffc90fdaa22168c234c4c6628b80dc1cd129024 @@ -116,3 +152,33 @@ func TestNewSRPClientSession(t *testing.T) { return } } + +func TestSRPClientSessionEphemeralKeyPub(t *testing.T) { + n := StripSpaceChars( + `ffffffffffffffffc90fdaa22168c234c4c6628b80dc1cd129024 + e088a67cc74020bbea63b139b22514a08798e3404ddef9519b3cd + 3a431b302b0a6df25f14374fe1356d6d51c245e485b576625e7ec + 6f44c42e9a637ed6b0bff5cb6f406b7edee386bfb5a899fa5ae9f + 24117c4b1fe649286651ece45b3dc2007cb8a163bf0598da48361 + c55d39a69163fa8fd24cf5f83655d23dca3ad961c62f356208552 + bb9ed529077096966d670c354e4abc9804f1746c08ca237327fff + fffffffffffff`) + g := "2" + k := "3" + ident := "s@ricketyspace.net" + session, err := NewSRPClientSession(n, g, k, ident) + if err != nil { + t.Errorf("Error: %v\n", err) + return + } + + pub, err := session.EphemeralKeyPub() + if err != nil { + t.Errorf("Error: %v\n", err) + return + } + if pub.Cmp(big.NewInt(0)) != 1 { + t.Errorf("Error: pub is <= 0") + return + } +} |