From 4795f4c737e59587d05d6eced2c86d3fc50ad42d Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 21 Jun 2013 13:23:52 +0200 Subject: conntrack: labels: skip labels with non-alnum characters Can always lift this restriction later but for now enforce strict label naming. This is mainly to make sure that e.g. using conntrack ... -o xml,connlabels will output the expected format, without nasty surprises. Signed-off-by: Florian Westphal --- src/conntrack/labels.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) (limited to 'src/conntrack/labels.c') diff --git a/src/conntrack/labels.c b/src/conntrack/labels.c index 7393c42..7dfb780 100644 --- a/src/conntrack/labels.c +++ b/src/conntrack/labels.c @@ -1,3 +1,4 @@ +#include #include #include "internal/internal.h" @@ -184,6 +185,30 @@ static struct nfct_labelmap *map_alloc(void) return map; } +/* + * We will only accept alpha numerical labels; else + * parses might choke on output when label named + * "foo;<&bar" exists. ASCII machines only. + * + * Avoids libc isalnum() etc. to avoid issues with locale + * settings. + */ +static bool label_is_sane(const char *label) +{ + for (;*label; label++) { + if (*label >= 'a' && *label <= 'z') + continue; + if (*label >= 'A' && *label <= 'Z') + continue; + if (*label >= '0' && *label <= '9') + continue; + if (*label == ' ' || *label == '-') + continue; + return false; + } + return true; +} + struct nfct_labelmap *__labelmap_new(const char *name) { struct nfct_labelmap *map; @@ -219,7 +244,8 @@ struct nfct_labelmap *__labelmap_new(const char *name) end = trim_label(end); if (!end) continue; - if (map_insert(map, end, bit) == 0) { + + if (label_is_sane(end) && map_insert(map, end, bit) == 0) { added++; if (maxbit < bit) maxbit = bit; -- cgit v1.2.3