summary refs log tree commit diff
diff options
context:
space:
mode:
authorJason A. Donenfeld <Jason@zx2c4.com>2014-01-16 19:47:35 +0100
committerJason A. Donenfeld <Jason@zx2c4.com>2014-01-16 19:47:35 +0100
commitdf00ab1096868b3cffe563c48de5572f78b50392 (patch)
treee58f6e5dbc25e06f96b3b59bc8349b7cf75e7677
parentb826537cb4aa2358027ffcb1dd6a87274734e962 (diff)
auth: lua string comparisons are time invariant
By default, strings are compared by hash, so we can remove this comment.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
-rw-r--r--filters/simple-authentication.lua4
1 files changed, 2 insertions, 2 deletions
diff --git a/filters/simple-authentication.lua b/filters/simple-authentication.lua
index 5935d08..5c4f074 100644
--- a/filters/simple-authentication.lua
+++ b/filters/simple-authentication.lua
@@ -45,7 +45,7 @@ function authenticate_post()
 
 	redirect_to(redirect)
 
-	-- TODO: Implement time invariant string comparison function to mitigate timing attack.
+	-- Lua hashes strings, so these comparisons are time invariant.
 	if password == nil or password ~= post["password"] then
 		set_cookie("cgitauth", "")
 	else
@@ -222,7 +222,7 @@ function validate_value(cookie)
 		return nil
 	end
 
-	-- TODO: implement time invariant comparison to prevent against timing attack.
+	-- Lua hashes strings, so these comparisons are time invariant.
 	if hmac ~= crypto.hmac.digest("sha1", value .. "|" .. tostring(expiration) .. "|" .. salt, secret) then
 		return nil
 	end