From 1d3deac2884002ed2dc64b44ddb133f3ad75766e Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 26 Apr 2013 10:21:17 +0200 Subject: examples/nf-queue: receive large gso packets Signed-off-by: Florian Westphal --- examples/nf-queue.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/examples/nf-queue.c b/examples/nf-queue.c index 6641a24..1f465ad 100644 --- a/examples/nf-queue.c +++ b/examples/nf-queue.c @@ -51,7 +51,7 @@ static int queue_cb(const struct nlmsghdr *nlh, void *data) { struct nfqnl_msg_packet_hdr *ph = NULL; struct nlattr *attr[NFQA_MAX+1] = {}; - uint32_t id = 0; + uint32_t id = 0, skbinfo; struct nfgenmsg *nfg; uint16_t plen; @@ -72,10 +72,32 @@ static int queue_cb(const struct nlmsghdr *nlh, void *data) plen = mnl_attr_get_payload_len(attr[NFQA_PAYLOAD]); /* void *payload = mnl_attr_get_payload(attr[NFQA_PAYLOAD]); */ + skbinfo = attr[NFQA_SKB_INFO] ? ntohl(mnl_attr_get_u32(attr[NFQA_SKB_INFO])) : 0; + + if (attr[NFQA_CAP_LEN]) { + uint32_t orig_len = ntohl(mnl_attr_get_u32(attr[NFQA_CAP_LEN])); + if (orig_len != plen) + printf("truncated "); + } + + if (skbinfo & NFQA_SKB_GSO) + printf("GSO "); + id = ntohl(ph->packet_id); - printf("packet received (id=%u hw=0x%04x hook=%u, payload len %u)\n", + printf("packet received (id=%u hw=0x%04x hook=%u, payload len %u", id, ntohs(ph->hw_protocol), ph->hook, plen); + /* + * ip/tcp checksums are not yet valid, e.g. due to GRO/GSO. + * The application should behave as if the checksums are correct. + * + * If these packets are later forwarded/sent out, the checksums will + * be corrected by kernel/hardware. + */ + if (skbinfo & NFQA_SKB_CSUMNOTREADY) + printf(", checksum not ready"); + puts(")"); + nfq_send_verdict(ntohs(nfg->res_id), id); return MNL_CB_OK; @@ -141,6 +163,9 @@ int main(int argc, char *argv[]) nlh = nfq_hdr_put(buf, NFQNL_MSG_CONFIG, queue_num); nfq_nlmsg_cfg_put_params(nlh, NFQNL_COPY_PACKET, 0xffff); + mnl_attr_put_u32(nlh, NFQA_CFG_FLAGS, htonl(NFQA_CFG_F_GSO)); + mnl_attr_put_u32(nlh, NFQA_CFG_MASK, htonl(NFQA_CFG_F_GSO)); + if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { perror("mnl_socket_send"); exit(EXIT_FAILURE); -- cgit v1.2.3