remove ethereum dependency

vm/randentropy/rand_entropy.go

@@ -0,0 +1,35 @@
+package randentropy
+
+import (
+	crand "crypto/rand"
+	"github.com/tendermint/tendermint/vm/sha3"
+	"io"
+)
+
+var Reader io.Reader = &randEntropy{}
+
+type randEntropy struct {
+}
+
+func (*randEntropy) Read(bytes []byte) (n int, err error) {
+	readBytes := GetEntropyCSPRNG(len(bytes))
+	copy(bytes, readBytes)
+	return len(bytes), nil
+}
+
+// TODO: copied from crypto.go , move to sha3 package?
+func Sha3(data []byte) []byte {
+	d := sha3.NewKeccak256()
+	d.Write(data)
+
+	return d.Sum(nil)
+}
+
+func GetEntropyCSPRNG(n int) []byte {
+	mainBuff := make([]byte, n)
+	_, err := io.ReadFull(crand.Reader, mainBuff)
+	if err != nil {
+		panic("reading from crypto/rand failed: " + err.Error())
+	}
+	return mainBuff
+}