2 files changed, 4 insertions, 11 deletions
diff --git a/vendor/golang.org/x/crypto/ssh/client_auth.go b/vendor/golang.org/x/crypto/ssh/client_auth.go
index f3265655..c611aeb6 100644
--- a/vendor/golang.org/x/crypto/ssh/client_auth.go
+++ b/vendor/golang.org/x/crypto/ssh/client_auth.go
@@ -471,7 +471,7 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
 		}
 
 		if len(answers) != len(prompts) {
-			return authFailure, nil, errors.New("ssh: not enough answers from keyboard-interactive callback")
+			return authFailure, nil, fmt.Errorf("ssh: incorrect number of answers from keyboard-interactive callback %d (expected %d)", len(answers), len(prompts))
 		}
 		responseLength := 1 + 4
 		for _, a := range answers {
diff --git a/vendor/golang.org/x/crypto/ssh/kex.go b/vendor/golang.org/x/crypto/ssh/kex.go
index 7eedb209..766e9293 100644
--- a/vendor/golang.org/x/crypto/ssh/kex.go
+++ b/vendor/golang.org/x/crypto/ssh/kex.go
@@ -557,8 +557,6 @@ type dhGEXSHA struct {
 	hashFunc crypto.Hash
 }
 
-const numMRTests = 64
-
 const (
 	dhGroupExchangeMinimumBits   = 2048
 	dhGroupExchangePreferredBits = 2048
@@ -602,15 +600,8 @@ func (gex dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshake
 	gex.p = kexDHGexGroup.P
 	gex.g = kexDHGexGroup.G
 
-	// Check if p is safe by verifing that p and (p-1)/2 are primes
-	one := big.NewInt(1)
-	var pHalf = &big.Int{}
-	pHalf.Rsh(gex.p, 1)
-	if !gex.p.ProbablyPrime(numMRTests) || !pHalf.ProbablyPrime(numMRTests) {
-		return nil, fmt.Errorf("ssh: server provided gex p is not safe")
-	}
-
 	// Check if g is safe by verifing that g > 1 and g < p - 1
+	one := big.NewInt(1)
 	var pMinusOne = &big.Int{}
 	pMinusOne.Sub(gex.p, one)
 	if gex.g.Cmp(one) != 1 && gex.g.Cmp(pMinusOne) != -1 {
@@ -618,6 +609,8 @@ func (gex dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshake
 	}
 
 	// Send GexInit
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
 	x, err := rand.Int(randSource, pHalf)
 	if err != nil {
 		return nil, err