diff --git a/Cargo.lock b/Cargo.lock
index 1aa2f9c..6cfb63a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -428,7 +428,7 @@ version = "0.1.0"
 dependencies = [
  "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "proptest 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proptest 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "ring 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1101,7 +1101,7 @@ dependencies = [
 
 [[package]]
 name = "proptest"
-version = "0.8.3"
+version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bit-set 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1112,7 +1112,7 @@ dependencies = [
  "quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex-syntax 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rusty-fork 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rusty-fork 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1300,13 +1300,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rusty-fork"
-version = "0.2.0"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "fnv 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "wait-timeout 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wait-timeout 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1935,7 +1935,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "wait-timeout"
-version = "0.1.5"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.42 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2146,7 +2146,7 @@ dependencies = [
 "checksum pkg-config 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)" = "110d5ee3593dbb73f56294327fe5668bcc997897097cbc76b51e7aed3f52452f"
 "checksum pretty_env_logger 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "26d3bc10ef768a4e8eae257706926f17c76b48b6efc65335cfce12527e7348d6"
 "checksum proc-macro2 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "effdb53b25cdad54f8f48843d67398f7ef2e14f12c1b4cb4effc549a6462a4d6"
-"checksum proptest 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3e22d80dbb4e76f01beabba9a2ee7c8de2e25b7a92b57702760216c4742b76e8"
+"checksum proptest 0.8.7 (registry+https://github.com/rust-lang/crates.io-index)" = "926d0604475349f463fe44130aae73f2294b5309ab2ca0310b998bd334ef191f"
 "checksum pulldown-cmark 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d6fdf85cda6cadfae5428a54661d431330b312bc767ddbc57adbedc24da66e32"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
@@ -2167,7 +2167,7 @@ dependencies = [
 "checksum resolv-conf 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c62bd95a41841efdf7fca2ae9951e64a8d8eae7e5da196d8ce489a2241491a92"
 "checksum ring 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "6f7d28b30a72c01b458428e0ae988d4149c20d902346902be881e3edc4bb325c"
 "checksum rustc-demangle 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "76d7ba1feafada44f2d38eed812bd2489a03c0f5abb975799251518b68848649"
-"checksum rusty-fork 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ea98d8d2644fd8b4946a2be90e8c6dc52b652e03079c46e134d9815062b9082d"
+"checksum rusty-fork 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "3dd93264e10c577503e926bd1430193eeb5d21b059148910082245309b424fae"
 "checksum ryu 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "b96a9549dc8d48f2c283938303c4b5a77aa29bfbc5b54b084fb1630408899a8f"
 "checksum safemem 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e27a8b19b835f7aea908818e871f5cc3a5a186550c30773be987e155e8163d8f"
 "checksum same-file 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "cfb6eded0b06a0b512c8ddbcf04089138c9b4362c2f696f3c3d76039d68f3637"
@@ -2241,7 +2241,7 @@ dependencies = [
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum version_check 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "7716c242968ee87e5542f8021178248f267f295a5c4803beae8b8b7fd9bc6051"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
-"checksum wait-timeout 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "b9f3bf741a801531993db6478b95682117471f76916f5e690dd8d45395b09349"
+"checksum wait-timeout 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9f200f5b12eb75f8c1ed65abd4b2db8a6e1b138a20de009dacee265a2498f3f6"
 "checksum walkdir 2.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "63636bd0eb3d00ccb8b9036381b526efac53caf112b7783b730ab3f8e44da369"
 "checksum want 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "a05d9d966753fa4b5c8db73fcab5eed4549cfe0e1e4e66911e5564a0085c35d1"
 "checksum widestring 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7157704c2e12e3d2189c507b7482c52820a16dfa4465ba91add92f266667cadb"
diff --git a/crypto/Cargo.toml b/crypto/Cargo.toml
index 6a25ea7..9e46613 100644
--- a/crypto/Cargo.toml
+++ b/crypto/Cargo.toml
@@ -10,4 +10,4 @@ hex = "0.3.2"
 ring = "0.12.1"
 
 [dev-dependencies]
-proptest = "0.8.1"
\ No newline at end of file
+proptest = "0.8.7"
\ No newline at end of file