diff --git a/demo/package-lock.json b/demo/package-lock.json
index 9931f52..c701a9e 100644
--- a/demo/package-lock.json
+++ b/demo/package-lock.json
@@ -1358,7 +1358,6 @@
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/bcrypt-pbkdf/-/bcrypt-pbkdf-1.0.1.tgz",
       "integrity": "sha1-Y7xdy2EzG5K8Bf1SiVPDNGKgb40=",
-      "optional": true,
       "requires": {
         "tweetnacl": "^0.14.3"
       }
@@ -2283,7 +2282,6 @@
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/ecc-jsbn/-/ecc-jsbn-0.1.1.tgz",
       "integrity": "sha1-D8c6ntXw1Tw4GTOYUj735UN3dQU=",
-      "optional": true,
       "requires": {
         "jsbn": "~0.1.0"
       }
@@ -3184,8 +3182,7 @@
         },
         "asn1": {
           "version": "0.2.3",
-          "bundled": true,
-          "optional": true
+          "bundled": true
         },
         "assert-plus": {
           "version": "0.2.0",
@@ -3215,7 +3212,6 @@
         "bcrypt-pbkdf": {
           "version": "1.0.1",
           "bundled": true,
-          "optional": true,
           "requires": {
             "tweetnacl": "^0.14.3"
           }
@@ -3299,7 +3295,6 @@
         "dashdash": {
           "version": "1.14.1",
           "bundled": true,
-          "optional": true,
           "requires": {
             "assert-plus": "^1.0.0"
           },
@@ -3342,7 +3337,6 @@
         "ecc-jsbn": {
           "version": "0.1.1",
           "bundled": true,
-          "optional": true,
           "requires": {
             "jsbn": "~0.1.0"
           }
@@ -3416,7 +3410,6 @@
         "getpass": {
           "version": "0.1.7",
           "bundled": true,
-          "optional": true,
           "requires": {
             "assert-plus": "^1.0.0"
           },
@@ -3536,7 +3529,6 @@
         "jodid25519": {
           "version": "1.0.2",
           "bundled": true,
-          "optional": true,
           "requires": {
             "jsbn": "~0.1.0"
           }
@@ -3828,29 +3820,6 @@
             "hoek": "2.x.x"
           }
         },
-        "sshpk": {
-          "version": "1.13.0",
-          "bundled": true,
-          "optional": true,
-          "requires": {
-            "asn1": "~0.2.3",
-            "assert-plus": "^1.0.0",
-            "bcrypt-pbkdf": "^1.0.0",
-            "dashdash": "^1.12.0",
-            "ecc-jsbn": "~0.1.1",
-            "getpass": "^0.1.1",
-            "jodid25519": "^1.0.0",
-            "jsbn": "~0.1.0",
-            "tweetnacl": "~0.14.0"
-          },
-          "dependencies": {
-            "assert-plus": {
-              "version": "1.0.0",
-              "bundled": true,
-              "optional": true
-            }
-          }
-        },
         "string-width": {
           "version": "1.0.2",
           "bundled": true,
@@ -5650,8 +5619,7 @@
     "jsbn": {
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/jsbn/-/jsbn-0.1.1.tgz",
-      "integrity": "sha1-peZUwuWi3rXyAdls77yoDA7y9RM=",
-      "optional": true
+      "integrity": "sha1-peZUwuWi3rXyAdls77yoDA7y9RM="
     },
     "jsdom": {
       "version": "9.12.0",
@@ -7995,6 +7963,11 @@
       "dev": true,
       "optional": true
     },
+    "safer-buffer": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/safer-buffer/-/safer-buffer-2.1.2.tgz",
+      "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg=="
+    },
     "sane": {
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/sane/-/sane-2.3.0.tgz",
@@ -8351,9 +8324,9 @@
       "dev": true
     },
     "sshpk": {
-      "version": "1.13.1",
-      "resolved": "https://registry.npmjs.org/sshpk/-/sshpk-1.13.1.tgz",
-      "integrity": "sha1-US322mKHFEMW3EwY/hzx2UBzm+M=",
+      "version": "1.16.1",
+      "resolved": "https://registry.npmjs.org/sshpk/-/sshpk-1.16.1.tgz",
+      "integrity": "sha512-HXXqVUq7+pcKeLqqZj6mHFUMvXtOJt1uoUx09pFW6011inTMxqI8BA8PM95myrIyyKwdnzjdFjLiE6KBPVtJIg==",
       "requires": {
         "asn1": "~0.2.3",
         "assert-plus": "^1.0.0",
@@ -8362,6 +8335,7 @@
         "ecc-jsbn": "~0.1.1",
         "getpass": "^0.1.1",
         "jsbn": "~0.1.0",
+        "safer-buffer": "^2.0.2",
         "tweetnacl": "~0.14.0"
       }
     },
@@ -8893,8 +8867,7 @@
     "tweetnacl": {
       "version": "0.14.5",
       "resolved": "https://registry.npmjs.org/tweetnacl/-/tweetnacl-0.14.5.tgz",
-      "integrity": "sha1-WuaBd/GS1EViadEIr6k/+HQ/T2Q=",
-      "optional": true
+      "integrity": "sha1-WuaBd/GS1EViadEIr6k/+HQ/T2Q="
     },
     "type-check": {
       "version": "0.3.2",
diff --git a/demo/yarn.lock b/demo/yarn.lock
index fc294f2..9d6aaaf 100644
--- a/demo/yarn.lock
+++ b/demo/yarn.lock
@@ -278,12 +278,14 @@ asap@~2.0.3:
   resolved "http://registry.npm.taobao.org/asap/download/asap-2.0.6.tgz#e50347611d7e690943208bbdafebcbc2fb866d46"
 
 asn1@~0.2.3:
-  version "0.2.3"
-  resolved "http://registry.npm.taobao.org/asn1/download/asn1-0.2.3.tgz#dac8787713c9966849fc8180777ebe9c1ddf3b86"
+  version "0.2.4"
+  resolved "https://registry.yarnpkg.com/asn1/-/asn1-0.2.4.tgz#8d2475dfab553bb33e77b54e59e880bb8ce23136"
+  dependencies:
+    safer-buffer "~2.1.0"
 
 assert-plus@1.0.0, assert-plus@^1.0.0:
   version "1.0.0"
-  resolved "http://registry.npm.taobao.org/assert-plus/download/assert-plus-1.0.0.tgz#f12e0f3c5d77b0b1cdd9146942e4e96c1e4dd525"
+  resolved "https://registry.yarnpkg.com/assert-plus/-/assert-plus-1.0.0.tgz#f12e0f3c5d77b0b1cdd9146942e4e96c1e4dd525"
 
 assert-plus@^0.2.0:
   version "0.2.0"
@@ -1043,8 +1045,8 @@ batch@0.5.3:
   resolved "http://registry.npm.taobao.org/batch/download/batch-0.5.3.tgz#3f3414f380321743bfc1042f9a83ff1d5824d464"
 
 bcrypt-pbkdf@^1.0.0:
-  version "1.0.1"
-  resolved "http://registry.npm.taobao.org/bcrypt-pbkdf/download/bcrypt-pbkdf-1.0.1.tgz#63bc5dcb61331b92bc05fd528953c33462a06f8d"
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/bcrypt-pbkdf/-/bcrypt-pbkdf-1.0.2.tgz#a4301d389b6a43f9b67ff3ca11a3f6637e360e9e"
   dependencies:
     tweetnacl "^0.14.3"
 
@@ -1573,7 +1575,7 @@ csurf@~1.8.3:
 
 dashdash@^1.12.0:
   version "1.14.1"
-  resolved "http://registry.npm.taobao.org/dashdash/download/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
+  resolved "https://registry.yarnpkg.com/dashdash/-/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
   dependencies:
     assert-plus "^1.0.0"
 
@@ -1717,10 +1719,11 @@ duplexer3@^0.1.4:
   resolved "http://registry.npm.taobao.org/duplexer3/download/duplexer3-0.1.4.tgz#ee01dd1cac0ed3cbc7fdbea37dc0a8f1ce002ce2"
 
 ecc-jsbn@~0.1.1:
-  version "0.1.1"
-  resolved "http://registry.npm.taobao.org/ecc-jsbn/download/ecc-jsbn-0.1.1.tgz#0fc73a9ed5f0d53c38193398523ef7e543777505"
+  version "0.1.2"
+  resolved "https://registry.yarnpkg.com/ecc-jsbn/-/ecc-jsbn-0.1.2.tgz#3a83a904e54353287874c564b7549386849a98c9"
   dependencies:
     jsbn "~0.1.0"
+    safer-buffer "^2.1.0"
 
 ecdsa-sig-formatter@1.0.9:
   version "1.0.9"
@@ -2311,7 +2314,7 @@ getenv@^0.7.0:
 
 getpass@^0.1.1:
   version "0.1.7"
-  resolved "http://registry.npm.taobao.org/getpass/download/getpass-0.1.7.tgz#5eff8e3e684d569ae4cb2b1282604e8ba62149fa"
+  resolved "https://registry.yarnpkg.com/getpass/-/getpass-0.1.7.tgz#5eff8e3e684d569ae4cb2b1282604e8ba62149fa"
   dependencies:
     assert-plus "^1.0.0"
 
@@ -3203,7 +3206,7 @@ js-yaml@^3.7.0:
 
 jsbn@~0.1.0:
   version "0.1.1"
-  resolved "http://registry.npm.taobao.org/jsbn/download/jsbn-0.1.1.tgz#a5e654c2e5a2deb5f201d96cefbca80c0ef2f513"
+  resolved "https://registry.yarnpkg.com/jsbn/-/jsbn-0.1.1.tgz#a5e654c2e5a2deb5f201d96cefbca80c0ef2f513"
 
 jsdom@^9.12.0:
   version "9.12.0"
@@ -4961,6 +4964,10 @@ safe-json-stringify@~1:
   version "1.0.4"
   resolved "http://registry.npm.taobao.org/safe-json-stringify/download/safe-json-stringify-1.0.4.tgz#81a098f447e4bbc3ff3312a243521bc060ef5911"
 
+safer-buffer@^2.0.2, safer-buffer@^2.1.0, safer-buffer@~2.1.0:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/safer-buffer/-/safer-buffer-2.1.2.tgz#44fa161b0187b9549dd84bb91802f9bd8385cd6a"
+
 sane@^2.0.0:
   version "2.2.0"
   resolved "http://registry.npm.taobao.org/sane/download/sane-2.2.0.tgz#d6d2e2fcab00e3d283c93b912b7c3a20846f1d56"
@@ -5226,17 +5233,17 @@ sprintf-js@~1.0.2:
   resolved "http://registry.npm.taobao.org/sprintf-js/download/sprintf-js-1.0.3.tgz#04e6926f662895354f3dd015203633b857297e2c"
 
 sshpk@^1.7.0:
-  version "1.13.1"
-  resolved "http://registry.npm.taobao.org/sshpk/download/sshpk-1.13.1.tgz#512df6da6287144316dc4c18fe1cf1d940739be3"
+  version "1.16.1"
+  resolved "https://registry.yarnpkg.com/sshpk/-/sshpk-1.16.1.tgz#fb661c0bef29b39db40769ee39fa70093d6f6877"
   dependencies:
     asn1 "~0.2.3"
     assert-plus "^1.0.0"
-    dashdash "^1.12.0"
-    getpass "^0.1.1"
-  optionalDependencies:
     bcrypt-pbkdf "^1.0.0"
+    dashdash "^1.12.0"
     ecc-jsbn "~0.1.1"
+    getpass "^0.1.1"
     jsbn "~0.1.0"
+    safer-buffer "^2.0.2"
     tweetnacl "~0.14.0"
 
 stack-trace@0.0.9:
@@ -5561,7 +5568,7 @@ tunnel-agent@^0.6.0:
 
 tweetnacl@^0.14.3, tweetnacl@~0.14.0:
   version "0.14.5"
-  resolved "http://registry.npm.taobao.org/tweetnacl/download/tweetnacl-0.14.5.tgz#5ae68177f192d4456269d108afa93ff8743f4f64"
+  resolved "https://registry.yarnpkg.com/tweetnacl/-/tweetnacl-0.14.5.tgz#5ae68177f192d4456269d108afa93ff8743f4f64"
 
 type-check@~0.3.2:
   version "0.3.2"