1 files changed, 52 insertions, 0 deletions
diff --git a/vendor/github.com/titanous/rocacheck/rocacheck.go b/vendor/github.com/titanous/rocacheck/rocacheck.go
new file mode 100644
index 000000000..e813579bb
--- /dev/null
+++ b/vendor/github.com/titanous/rocacheck/rocacheck.go
@@ -0,0 +1,52 @@
+// Package rocacheck checks if a key was generated by broken Infineon code and
+// is vulnerable to factorization via the Return of Coppersmith's Attack (ROCA)
+// / CVE-2017-15361.
+package rocacheck
+
+import (
+	"crypto/rsa"
+	"math/big"
+)
+
+type test struct {
+	Prime        *big.Int
+	Fingerprints map[int64]struct{}
+}
+
+var tests = make([]test, 17)
+
+func init() {
+	bigOne := big.NewInt(1)
+	n := &big.Int{}
+	// relations table from https://github.com/crocs-muni/roca/pull/40
+	for i, r := range [][2]int64{
+		{2, 11}, {6, 13}, {8, 17}, {9, 19}, {3, 37}, {26, 53}, {20, 61},
+		{35, 71}, {24, 73}, {13, 79}, {6, 97}, {51, 103}, {53, 107},
+		{54, 109}, {42, 127}, {50, 151}, {78, 157},
+	} {
+		fps := make(map[int64]struct{})
+		bp := big.NewInt(r[1])
+		br := big.NewInt(r[0])
+		for j := int64(0); j < r[1]; j++ {
+			if n.Exp(big.NewInt(j), br, bp).Cmp(bigOne) == 0 {
+				fps[j] = struct{}{}
+			}
+		}
+		tests[i] = test{
+			Prime:        big.NewInt(r[1]),
+			Fingerprints: fps,
+		}
+	}
+}
+
+// IsWeak returns true if a RSA public key is vulnerable to Return of
+// Coppersmith's Attack (ROCA).
+func IsWeak(k *rsa.PublicKey) bool {
+	tmp := &big.Int{}
+	for _, t := range tests {
+		if _, ok := t.Fingerprints[tmp.Mod(k.N, t.Prime).Int64()]; !ok {
+			return false
+		}
+	}
+	return true
+}