diff --git a/.travis.yml b/.travis.yml
index 21260a8..0be4bde 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,7 +4,9 @@ python:
   - 2.7
 before_install:
   - sudo apt-get update -qq
-  - sudo apt-get install -qq build-essential libssl-dev swig libevent-dev python-gevent python-m2crypto
-  - pip install gevent m2crypto
+  - sudo apt-get install -qq build-essential libssl-dev swig libevent-dev python-gevent python-m2crypto python-numpy
+  - pip install gevent m2crypto salsa20
 script:
-  - python test.py
+  - python test.py -c test/table.json
+  - python test.py -c test/aes.json
+  - python test.py -c test/salsa20.json
diff --git a/README.md b/README.md
index c541a90..356bc57 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ Install Shadowsocks.
 
 #### Debian / Ubuntu:
 
-    apt-get install python-gevent python-m2crypto
+    apt-get install python-pip python-gevent python-m2crypto
     pip install shadowsocks
 
 #### CentOS:
@@ -94,6 +94,20 @@ You can use args to override settings from `config.json`.
     ssserver -p server_port -k password -m bf-cfb
     ssserver -c /etc/shadowsocks/config.json
 
+Salsa20
+-------
+
+Salsa20 is a fast stream cipher.
+
+Use "salsa20-ctr" in shadowsocks.json.
+
+And install these packages:
+
+#### Debian / Ubuntu:
+
+    apt-get install python-numpy
+    pip install salsa20
+
 Wiki
 ----
 
diff --git a/config.json b/config.json
index 5c9656b..026ed38 100644
--- a/config.json
+++ b/config.json
@@ -4,7 +4,7 @@
     "local_port":1080,
     "password":"barfoo!",
     "timeout":300,
-    "method":"table",
+    "method":"aes-256-cfb",
     "local_address":"127.0.0.1",
     "fast_open":false
 }
diff --git a/shadowsocks/encrypt.py b/shadowsocks/encrypt.py
index fcaad99..267565c 100644
--- a/shadowsocks/encrypt.py
+++ b/shadowsocks/encrypt.py
@@ -151,7 +151,8 @@ class Encryptor(object):
         if m:
             key, iv_ = EVP_BytesToKey(password, m[0], m[1])
             if iv is None:
-                iv = iv_[:m[1]]
+                iv = iv_
+            iv = iv[:m[1]]
             if op == 1:
                 self.cipher_iv = iv[:m[1]]  # this iv is for cipher not decipher
             if method != 'salsa20-ctr':
diff --git a/test.py b/test.py
index e2b6f16..130aee4 100755
--- a/test.py
+++ b/test.py
@@ -82,9 +82,9 @@ decrypt_table = string.maketrans(encrypt_table, string.maketrans('', ''))
 for i in range(0, 256):
     assert(target2[0][i] == ord(encrypt_table[i]))
     assert(target2[1][i] == ord(decrypt_table[i]))
-p1 = Popen(['python', 'shadowsocks/server.py', '-c', 'test/config.json'], shell=False, bufsize=0, stdin=PIPE, 
+p1 = Popen(['python', 'shadowsocks/server.py', '-c', sys.argv[-1]], shell=False, bufsize=0, stdin=PIPE, 
     stdout=PIPE, stderr=PIPE, close_fds=True)
-p2 = Popen(['python', 'shadowsocks/local.py', '-c', 'test/config.json'], shell=False, bufsize=0, stdin=PIPE,
+p2 = Popen(['python', 'shadowsocks/local.py', '-c', sys.argv[-1]], shell=False, bufsize=0, stdin=PIPE,
     stdout=PIPE, stderr=PIPE, close_fds=True)
 p3 = None
 
diff --git a/test/config.json b/test/aes.json
similarity index 100%
rename from test/config.json
rename to test/aes.json
diff --git a/test/salsa20.json b/test/salsa20.json
new file mode 100644
index 0000000..8035f06
--- /dev/null
+++ b/test/salsa20.json
@@ -0,0 +1,10 @@
+{
+    "server":"127.0.0.1",
+    "server_port":8388,
+    "local_port":1080,
+    "password":"barfoo!",
+    "timeout":300,
+    "method":"salsa20-ctr",
+    "local_address":"127.0.0.1",
+    "fast_open":false
+}
diff --git a/test/table.json b/test/table.json
new file mode 100644
index 0000000..4b1c984
--- /dev/null
+++ b/test/table.json
@@ -0,0 +1,10 @@
+{
+    "server":"127.0.0.1",
+    "server_port":8388,
+    "local_port":1080,
+    "password":"barfoo!",
+    "timeout":300,
+    "method":"table",
+    "local_address":"127.0.0.1",
+    "fast_open":false
+}