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 <fw@xxxxxxxxx>
---
I've split this into a separate patch since it has noting
to do with the nfct_snprintf change.
src/conntrack/labels.c | 28 +++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)
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 <stdbool.h>
#include <stdint.h>
#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;
--
1.8.1.5
--
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