1. struct nlattr *attr[NFQA_MAX+1] must be initialized.
Otherwise, attr[FOO] might be non-null after parsing
even if that attribute isn't present in the message.
2. mnl_attr_get_payload will never return NULL (if the
attribute is NULL, it returns MNL_ATTR_HDRLEN.)
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
examples/nf-queue.c | 26 ++++++++++++++------------
1 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/examples/nf-queue.c b/examples/nf-queue.c
index 4d56751..3d64386 100644
--- a/examples/nf-queue.c
+++ b/examples/nf-queue.c
@@ -31,12 +31,11 @@ nfq_hdr_put(char *buf, int type, uint32_t queue_num)
return nlh;
}
-static int
+static void
nfq_send_verdict(int queue_num, uint32_t id)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
- int ret;
nlh = nfq_hdr_put(buf, NFQNL_MSG_VERDICT, queue_num);
nfq_nlmsg_verdict_put(nlh, id, NF_ACCEPT);
@@ -45,16 +44,15 @@ nfq_send_verdict(int queue_num, uint32_t id)
perror("mnl_socket_send");
exit(EXIT_FAILURE);
}
-
- return ret;
}
static int queue_cb(const struct nlmsghdr *nlh, void *data)
{
struct nfqnl_msg_packet_hdr *ph = NULL;
- struct nlattr *attr[NFQA_MAX+1];
+ struct nlattr *attr[NFQA_MAX+1] = {};
uint32_t id = 0;
struct nfgenmsg *nfg;
+ uint16_t plen;
if (nfq_nlmsg_parse(nlh, attr) < 0) {
perror("problems parsing");
@@ -63,18 +61,22 @@ static int queue_cb(const struct nlmsghdr *nlh, void *data)
nfg = mnl_nlmsg_get_payload(nlh);
- ph = (struct nfqnl_msg_packet_hdr *)
- mnl_attr_get_payload(attr[NFQA_PACKET_HDR]);
- if (ph == NULL) {
- perror("problems retrieving metaheader");
+ if (attr[NFQA_PACKET_HDR] == NULL) {
+ fputs("metaheader not set\n", stderr);
return MNL_CB_ERROR;
}
- id = ntohl(ph->packet_id);
+ ph = mnl_attr_get_payload(attr[NFQA_PACKET_HDR]);
- printf("packet received (id=%u hw=0x%04x hook=%u)\n",
- id, ntohs(ph->hw_protocol), ph->hook);
+ plen = mnl_attr_get_payload_len(attr[NFQA_PAYLOAD]);
+ /* void *payload = mnl_attr_get_payload(attr[NFQA_PAYLOAD]); */
+
+ id = ntohl(ph->packet_id);
+ printf("packet received (id=%u hw=0x%04x hook=%u, payload len %u)\n",
+ id, ntohs(ph->hw_protocol), ph->hook, plen);
+ puts("sleep 10 seconds");
+ sleep(10);
nfq_send_verdict(ntohs(nfg->res_id), id);
return MNL_CB_OK;
--
1.7.8.6
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
