filters: migrate from luacrypto to luaossl

luaossl has no upstream anymore and doesn't support OpenSSL 1.1,
whereas luaossl is quite active.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 19 insertions, 12 deletions

@@ -1,8 +1,8 @@
 -- This script may be used with the auth-filter. Be sure to configure it as you wish.
 --
 -- Requirements:
---      luacrypto >= 0.3
---      <http://mkottman.github.io/luacrypto/>
+--      luaossl
+--      <http://25thandclement.com/~william/projects/luaossl.html>
 --      lualdap >= 1.2
 --      <https://git.zx2c4.com/lualdap/about/>
 --      luaposix
@@ -10,9 +10,9 @@
 --
 local sysstat = require("posix.sys.stat")
 local unistd = require("posix.unistd")
-local crypto = require("crypto")
 local lualdap = require("lualdap")
-
+local rand = require("openssl.rand")
+local hmac = require("openssl.hmac")
 
 --
 --
@@ -226,6 +226,13 @@ function get_cookie(cookies, name)
         return string.match(cookies, ";" .. name .. "=(.-);")
 end
 
+function tohex(b)
+        local x = ""
+        for i = 1, #b do
+                x = x .. string.format("%.2x", string.byte(b, i))
+        end
+        return x
+end
 
 --
 --
@@ -243,12 +250,12 @@ function get_secret()
         local secret_file = io.open(secret_filename, "r")
         if secret_file == nil then
                 local old_umask = sysstat.umask(63)
-                local temporary_filename = secret_filename .. ".tmp." .. crypto.hex(crypto.rand.bytes(16))
+                local temporary_filename = secret_filename .. ".tmp." .. tohex(rand.bytes(16))
                 local temporary_file = io.open(temporary_filename, "w")
                 if temporary_file == nil then
                         os.exit(177)
                 end
-                temporary_file:write(crypto.hex(crypto.rand.bytes(32)))
+                temporary_file:write(tohex(rand.bytes(32)))
                 temporary_file:close()
                 unistd.link(temporary_filename, secret_filename) -- Intentionally fails in the case that another process is doing the same.
                 unistd.unlink(temporary_filename)
@@ -273,7 +280,7 @@ function validate_value(expected_field, cookie)
         local field = ""
         local expiration = 0
         local salt = ""
-        local hmac = ""
+        local chmac = ""
 
         if cookie == nil or cookie:len() < 3 or cookie:sub(1, 1) == "|" then
                 return nil
@@ -292,19 +299,19 @@ function validate_value(expected_field, cookie)
                 elseif i == 3 then
                         salt = component
                 elseif i == 4 then
-                        hmac = component
+                        chmac = component
                 else
                         break
                 end
                 i = i + 1
         end
 
-        if hmac == nil or hmac:len() == 0 then
+        if chmac == nil or chmac:len() == 0 then
                 return nil
         end
 
         -- Lua hashes strings, so these comparisons are time invariant.
-        if hmac ~= crypto.hmac.digest("sha256", field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt, get_secret()) then
+        if chmac ~= tohex(hmac.new(get_secret(), "sha256"):final(field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt)) then
                 return nil
         end
 
@@ -325,11 +332,11 @@ function secure_value(field, value, expiration)
         end
 
         local authstr = ""
-        local salt = crypto.hex(crypto.rand.bytes(16))
+        local salt = tohex(rand.bytes(16))
         value = url_encode(value)
         field = url_encode(field)
         authstr = field .. "|" .. value .. "|" .. tostring(expiration) .. "|" .. salt
-        authstr = authstr .. "|" .. crypto.hmac.digest("sha256", authstr, get_secret())
+        authstr = authstr .. "|" .. tohex(hmac.new(get_secret(), "sha256"):final(authstr))
         return authstr
 end