diff --git a/vendor/github.com/zclconf/go-cty/cty/set_internals.go b/vendor/github.com/zclconf/go-cty/cty/set_internals.go
index ce738dbe6..1d7a731aa 100644
--- a/vendor/github.com/zclconf/go-cty/cty/set_internals.go
+++ b/vendor/github.com/zclconf/go-cty/cty/set_internals.go
@@ -19,12 +19,24 @@ type setRules struct {
 	Type Type
 }
 
+// Hash returns a hash value for the receiver that can be used for equality
+// checks where some inaccuracy is tolerable.
+//
+// The hash function is value-type-specific, so it is not meaningful to compare
+// hash results for values of different types.
+//
+// This function is not safe to use for security-related applications, since
+// the hash used is not strong enough.
+func (val Value) Hash() int {
+	hashBytes := makeSetHashBytes(val)
+	return int(crc32.ChecksumIEEE(hashBytes))
+}
+
 func (r setRules) Hash(v interface{}) int {
-	hashBytes := makeSetHashBytes(Value{
+	return Value{
 		ty: r.Type,
 		v:  v,
-	})
-	return int(crc32.ChecksumIEEE(hashBytes))
+	}.Hash()
 }
 
 func (r setRules) Equivalent(v1 interface{}, v2 interface{}) bool {
diff --git a/vendor/github.com/zclconf/go-cty/cty/unknown_as_null.go b/vendor/github.com/zclconf/go-cty/cty/unknown_as_null.go
new file mode 100644
index 000000000..cfd4a4253
--- /dev/null
+++ b/vendor/github.com/zclconf/go-cty/cty/unknown_as_null.go
@@ -0,0 +1,64 @@
+package cty
+
+// UnknownAsNull returns a value of the same type as the given value but
+// with any unknown values (including nested values) replaced with null
+// values of the same type.
+//
+// This can be useful if a result is to be serialized in a format that can't
+// represent unknowns, such as JSON, as long as the caller does not need to
+// retain the unknown value information.
+func UnknownAsNull(val Value) Value {
+	if !val.IsKnown() {
+		return NullVal(val.Type())
+	}
+
+	ty := val.Type()
+	switch {
+	case ty.IsListType() || ty.IsTupleType() || ty.IsSetType():
+		length := val.LengthInt()
+		if length == 0 {
+			// If there are no elements then we can't have unknowns
+			return val
+		}
+		vals := make([]Value, 0, length)
+		it := val.ElementIterator()
+		for it.Next() {
+			_, v := it.Element()
+			vals = append(vals, UnknownAsNull(v))
+		}
+		switch {
+		case ty.IsListType():
+			return ListVal(vals)
+		case ty.IsTupleType():
+			return TupleVal(vals)
+		default:
+			return SetVal(vals)
+		}
+	case ty.IsMapType() || ty.IsObjectType():
+		var length int
+		switch {
+		case ty.IsMapType():
+			length = val.LengthInt()
+		default:
+			length = len(val.Type().AttributeTypes())
+		}
+		if length == 0 {
+			// If there are no elements then we can't have unknowns
+			return val
+		}
+		vals := make(map[string]Value, length)
+		it := val.ElementIterator()
+		for it.Next() {
+			k, v := it.Element()
+			vals[k.AsString()] = UnknownAsNull(v)
+		}
+		switch {
+		case ty.IsMapType():
+			return MapVal(vals)
+		default:
+			return ObjectVal(vals)
+		}
+	}
+
+	return val
+}
diff --git a/vendor/github.com/zclconf/go-cty/cty/value_ops.go b/vendor/github.com/zclconf/go-cty/cty/value_ops.go
index 967aa761d..2089fb324 100644
--- a/vendor/github.com/zclconf/go-cty/cty/value_ops.go
+++ b/vendor/github.com/zclconf/go-cty/cty/value_ops.go
@@ -800,6 +800,10 @@ func (val Value) LengthInt() int {
 		// For tuples, we can return the length even if the value is not known.
 		return val.Type().Length()
 	}
+	if val.Type().IsObjectType() {
+		// For objects, the length is the number of attributes associated with the type.
+		return len(val.Type().AttributeTypes())
+	}
 	if !val.IsKnown() {
 		panic("value is not known")
 	}
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 9d78e42d7..a5b73e582 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -2420,46 +2420,46 @@
 			"revisionTime": "2016-10-29T10:40:18Z"
 		},
 		{
-			"checksumSHA1": "lGCvuEPfb2vhxEgYamNhnd1jYH8=",
+			"checksumSHA1": "4REWNRi5Dg7Kxj1US72+/oVii3Q=",
 			"path": "github.com/zclconf/go-cty/cty",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "gDpi8g5VxCRM3JKm/kaYlGdFUdQ=",
 			"path": "github.com/zclconf/go-cty/cty/convert",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "MyyLCGg3RREMllTJyK6ehZl/dHk=",
 			"path": "github.com/zclconf/go-cty/cty/function",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "4R+DQqBew6i9a4lYiLZW1OXVwTI=",
 			"path": "github.com/zclconf/go-cty/cty/function/stdlib",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "tmCzwfNXOEB1sSO7TKVzilb2vjA=",
 			"path": "github.com/zclconf/go-cty/cty/gocty",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "1ApmO+Q33+Oem/3f6BU6sztJWNc=",
 			"path": "github.com/zclconf/go-cty/cty/json",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "y5Sk+n6SOspFj8mlyb8swr4DMIs=",
 			"path": "github.com/zclconf/go-cty/cty/set",
-			"revision": "49fa5e03c418f95f78684c91e155af06aa901a32",
-			"revisionTime": "2018-03-02T16:03:48Z"
+			"revision": "b7d1e828d86e99040528ce06ce970382c7813f96",
+			"revisionTime": "2018-03-26T23:07:54Z"
 		},
 		{
 			"checksumSHA1": "vE43s37+4CJ2CDU6TlOUOYE0K9c=",