For debugging purposes, it can be useful to be able to retrieve keys.
Add a "iw key get" command, to be able to retrieve keys when the key
index is known. A new "key" section is also introduced, in preparation
for future key-related commands.
Example retrieving a pairwise key:
iw dev wlan0 key get 0 02:02:03:04:05:06
Example retrieving a group key:
iw dev wlan0 key get 1
Note that only the outer ATTR_KEY_DATA (and seq) is reported, the
nested KEY_DATA (and seq) within ATTR_KEY is not.
Signed-off-by: Raphaël Mélotte <raphael.melotte@xxxxxxx>
---
Changes v2 -> v3:
- Check parsing of index.
- Move pairwise type before argv++ and add line break.
Changes v1 -> v2:
- Introduce a 'key' section and update commit message
- Fix documentation (and remove pairwise flag)
- Return error when MAC is invalid
- Rebase on master
keys.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 83 insertions(+)
create mode 100644 keys.c
diff --git a/keys.c b/keys.c
new file mode 100644
index 0000000..65aa426
--- /dev/null
+++ b/keys.c
@@ -0,0 +1,83 @@
+#include <errno.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/family.h>
+#include <netlink/genl/ctrl.h>
+#include <netlink/msg.h>
+#include <netlink/attr.h>
+#include "nl80211.h"
+#include "iw.h"
+
+SECTION(key);
+
+static int print_keys(struct nl_msg *msg, void *arg)
+{
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *tb[NL80211_ATTR_MAX + 1];
+
+ nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL);
+
+ if (!tb[NL80211_ATTR_KEY_IDX]) {
+ fprintf(stderr, "KEY_IDX missing!\n");
+ return NL_SKIP;
+ }
+
+ if (!tb[NL80211_ATTR_KEY_DATA]) {
+ fprintf(stderr, "ATTR_KEY_DATA missing!\n");
+ return NL_SKIP;
+ }
+
+ iw_hexdump("Key", nla_data(tb[NL80211_ATTR_KEY_DATA]),
+ nla_len(tb[NL80211_ATTR_KEY_DATA]));
+
+ if (!tb[NL80211_ATTR_KEY_SEQ]) {
+ fprintf(stderr, "ATTR_KEY_SEQ missing!\n");
+ return NL_SKIP;
+ }
+
+ iw_hexdump("Key seq", nla_data(tb[NL80211_ATTR_KEY_SEQ]),
+ nla_len(tb[NL80211_ATTR_KEY_SEQ]));
+
+ return NL_OK;
+}
+
+static int handle_get_key(struct nl80211_state *state,
+ struct nl_msg *msg, int argc, char **argv,
+ enum id_input id)
+{
+ char *end;
+ unsigned char mac[6];
+
+ /* key index */
+ if (argc) {
+ nla_put_u8(msg, NL80211_ATTR_KEY_IDX, strtoul(argv[0], &end, 10));
+ if (*end != '\0')
+ return -EINVAL;
+ argv++;
+ argc--;
+ }
+
+ /* mac */
+ if (argc) {
+ if (mac_addr_a2n(mac, argv[0]) == 0) {
+ NLA_PUT(msg, NL80211_ATTR_MAC, 6, mac);
+ nla_put_u32(msg, NL80211_ATTR_KEY_TYPE,
+ NL80211_KEYTYPE_PAIRWISE);
+ argv++;
+ argc--;
+ } else {
+ return -EINVAL;
+ }
+ } else {
+ nla_put_u32(msg, NL80211_ATTR_KEY_TYPE, NL80211_KEYTYPE_GROUP);
+ }
+
+ register_handler(print_keys, NULL);
+ return 0;
+
+ nla_put_failure:
+ return -ENOSPC;
+}
+COMMAND(key, get, "<key index> <MAC address>",
+ NL80211_CMD_GET_KEY, 0, CIB_NETDEV, handle_get_key,
+ "Retrieve a key and key sequence.\n");
--
2.38.1
