[PATCH] Handle preshared CKN sizes from 1 to 32 octets

[Jaap Keuter]

IEEE802.1X-2010 section 9.3.1 states that the CKN comprises of 1 to 32
octets, and no further restrictions are placed on it. Therefore change
the code reading the preshared CKN so that these sizes are accepted.

Signed-off-by: Jaap Keuter <jaap.keuter at xs4all.nl>
---
 wpa_supplicant/config.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/wpa_supplicant/config.c b/wpa_supplicant/config.c
index 9ef11d86d..a4ff7f998 100644
--- a/wpa_supplicant/config.c
+++ b/wpa_supplicant/config.c
@@ -1898,8 +1898,16 @@ static int wpa_config_parse_mka_ckn(const struct parse_data *data,
 				    struct wpa_ssid *ssid, int line,
 				    const char *value)
 {
-	if (hexstr2bin(value, ssid->mka_ckn, MACSEC_CKN_LEN) ||
-	    value[MACSEC_CKN_LEN * 2] != '\0') {
+	size_t ckn_str_len = os_strlen(value);
+
+	if (ckn_str_len == 0 || (ckn_str_len & 1) == 1 ||
+		ckn_str_len > MACSEC_CKN_LEN * 2) {
+		wpa_printf(MSG_ERROR, "Line %d: Invalid size MKA-CKN '%s'.",
+			   line, value);
+		return -1;
+	}
+
+	if (hexstr2bin(value, ssid->mka_ckn, ckn_str_len / 2)) {
 		wpa_printf(MSG_ERROR, "Line %d: Invalid MKA-CKN '%s'.",
 			   line, value);
 		return -1;
-- 
2.11.0