From 72cbc106d95fb18892c739f128d29d4f54179771 Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Wed, 16 Jul 2014 21:55:42 +0200 Subject: [PATCH] Remove quadratic complexity from openvpn_base64_decode() Every four input characters, openvpn_base64_decode called token_decode, which in turn called strlen() on the remaining input. This means that base64 decoding in openvpn had quadratic complexity. All we really need to know is whether the token is complete, so replace the check to check just that, and make the complexity linear wrt the input length. Signed-off-by: Steffan Karger Acked-by: Gert Doering Message-Id: <5408494D.7050407@fox-it.com> URL: http://article.gmane.org/gmane.network.openvpn.devel/9016 Signed-off-by: Gert Doering (cherry picked from commit 25e1ec71dd150e803c0a25308c193fea124c7b7a) --- src/openvpn/base64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/openvpn/base64.c b/src/openvpn/base64.c index bb89aae38..7dccec299 100644 --- a/src/openvpn/base64.c +++ b/src/openvpn/base64.c @@ -110,7 +110,7 @@ token_decode(const char *token) int i; unsigned int val = 0; int marker = 0; - if (strlen(token) < 4) + if (!token[0] || !token[1] || !token[2] || !token[3]) return DECODE_ERROR; for (i = 0; i < 4; i++) { val *= 64; -- 2.47.3