With the advent of nfq_run_cb() and pktb_populate(),
there is no longer ever a buffer tacked on the end of a struct pktbuff.
Now that struct pktbuff is purely a buffer descriptor, there seems little
point in keeping it opaque so expose it.
Some code simplification ensues: the new callback function prototype only
differs from the old one in having 1 extra arg being available free space.
An application creates a struct pktbuff instance by just declaring it.
pktb_populate() zeroises pktb because it's no longer guaranteed zero.
As before, no new doxygen documentation until function prototypes are agreed,
but examples/nf-queue.c is updated.
Signed-off-by: Duncan Roe <duncan_roe@xxxxxxxxxxxxxxx>
---
v3: New patch
examples/nf-queue.c | 6 +++---
include/libnetfilter_queue/callback.h | 2 +-
include/libnetfilter_queue/pktbuff.h | 13 ++++++++++++-
src/extra/callback.c | 4 +---
src/extra/pktbuff.c | 1 +
src/internal.h | 14 +-------------
6 files changed, 19 insertions(+), 21 deletions(-)
diff --git a/examples/nf-queue.c b/examples/nf-queue.c
index 4074e5a..f330b97 100644
--- a/examples/nf-queue.c
+++ b/examples/nf-queue.c
@@ -49,11 +49,12 @@ nfq_send_verdict(int queue_num, uint32_t id)
}
static int queue_cb(const struct nlmsghdr *nlh, void *data,
- struct pkt_buff *supplied_pktb, size_t supplied_extra)
+ size_t supplied_extra)
{
struct nfqnl_msg_packet_hdr *ph = NULL;
struct nlattr *attr[NFQA_MAX+1] = {};
struct pkt_buff *pktb;
+ struct pkt_buff pkt_b;
uint32_t id = 0, skbinfo;
struct nfgenmsg *nfg;
uint8_t *payload;
@@ -77,8 +78,7 @@ static int queue_cb(const struct nlmsghdr *nlh, void *data,
plen = mnl_attr_get_payload_len(attr[NFQA_PAYLOAD]);
payload = mnl_attr_get_payload(attr[NFQA_PAYLOAD]);
- pktb = pktb_populate(supplied_pktb, AF_INET, payload, plen,
- supplied_extra);
+ pktb = pktb_populate(&pkt_b, AF_INET, payload, plen, supplied_extra);
skbinfo = attr[NFQA_SKB_INFO] ? ntohl(mnl_attr_get_u32(attr[NFQA_SKB_INFO])) : 0;
diff --git a/include/libnetfilter_queue/callback.h b/include/libnetfilter_queue/callback.h
index 27bfe31..756cb38 100644
--- a/include/libnetfilter_queue/callback.h
+++ b/include/libnetfilter_queue/callback.h
@@ -4,7 +4,7 @@
struct nlattr;
struct pkt_buff;
-typedef int (*nfq_cb_t)(const struct nlmsghdr *nlh, void *data, struct pkt_buff *pktb, size_t extra);
+typedef int (*nfq_cb_t)(const struct nlmsghdr *nlh, void *data, size_t extra);
int nfq_cb_run(const void *buf, size_t buflen, size_t bufcap, unsigned int portid, nfq_cb_t cb_data, void *data);
diff --git a/include/libnetfilter_queue/pktbuff.h b/include/libnetfilter_queue/pktbuff.h
index 33829cc..7ad7cb1 100644
--- a/include/libnetfilter_queue/pktbuff.h
+++ b/include/libnetfilter_queue/pktbuff.h
@@ -1,7 +1,18 @@
#ifndef _PKTBUFF_H_
#define _PKTBUFF_H_
-struct pkt_buff;
+struct pkt_buff {
+ uint8_t *mac_header;
+ uint8_t *network_header;
+ uint8_t *transport_header;
+
+ uint8_t *data;
+
+ uint32_t len;
+ uint32_t data_len;
+
+ bool mangled;
+};
struct pkt_buff *pktb_alloc(int family, void *data, size_t len, size_t extra);
void pktb_free(struct pkt_buff *pktb);
diff --git a/src/extra/callback.c b/src/extra/callback.c
index dee6fc2..23e88f7 100644
--- a/src/extra/callback.c
+++ b/src/extra/callback.c
@@ -31,10 +31,9 @@ struct data_carrier
static int local_cb(const struct nlmsghdr *nlh, void *data)
{
- struct pkt_buff pktb_instance = { };
struct data_carrier *d = (struct data_carrier *)data;
- return d->cb_func(nlh, d->data, &pktb_instance, d->bufcap - d->buflen);
+ return d->cb_func(nlh, d->data, d->bufcap - d->buflen);
}
EXPORT_SYMBOL int nfq_cb_run(const void *buf, size_t buflen, size_t bufcap,
@@ -54,6 +53,5 @@ EXPORT_SYMBOL int nfq_cb_run(const void *buf, size_t buflen, size_t bufcap,
return MNL_CB_ERROR;
}
-
return mnl_cb_run(buf, buflen, 0, portid, local_cb, &dc);
}
diff --git a/src/extra/pktbuff.c b/src/extra/pktbuff.c
index 86d8fe6..ae3e454 100644
--- a/src/extra/pktbuff.c
+++ b/src/extra/pktbuff.c
@@ -125,6 +125,7 @@ EXPORT_SYMBOL
struct pkt_buff *pktb_populate(struct pkt_buff *pktb, int family, void *data,
size_t len, size_t extra)
{
+ memset(pktb, 0, sizeof *pktb);
pktb_setup_metadata(pktb, data, len, extra);
if (__pktb_setup(family, pktb) < 0)
pktb = NULL;
diff --git a/src/internal.h b/src/internal.h
index ae849d6..6adf3d1 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -4,6 +4,7 @@
#include "config.h"
#include <stdint.h>
#include <stdbool.h>
+#include <libnetfilter_queue/pktbuff.h>
#ifdef HAVE_VISIBILITY_HIDDEN
# define EXPORT_SYMBOL __attribute__((visibility("default")))
#else
@@ -18,19 +19,6 @@ uint16_t nfq_checksum_tcpudp_ipv4(struct iphdr *iph, uint16_t protonum);
uint16_t nfq_checksum_tcpudp_ipv6(struct ip6_hdr *ip6h, void *transport_hdr,
uint16_t protonum);
-struct pkt_buff {
- uint8_t *mac_header;
- uint8_t *network_header;
- uint8_t *transport_header;
-
- uint8_t *data;
-
- uint32_t len;
- uint32_t data_len;
-
- bool mangled;
-};
-
static inline uint8_t *pktb_tail(struct pkt_buff *pktb)
{
return pktb->data + pktb->len;
--
2.17.5
