* [PATCH bpf-next v2 01/11] bpf: adding bpf_xdp_adjust_tail helper
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 16:56 ` Alexei Starovoitov
2018-04-18 4:29 ` [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail Nikita V. Shirokov
` (10 subsequent siblings)
11 siblings, 1 reply; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann; +Cc: netdev, Nikita V. Shirokov
Adding new bpf helper which would allow us to manipulate
xdp's data_end pointer, and allow us to reduce packet's size
indended use case: to generate ICMP messages from XDP context,
where such message would contain truncated original packet.
---
include/uapi/linux/bpf.h | 10 +++++++++-
net/core/filter.c | 29 ++++++++++++++++++++++++++++-
2 files changed, 37 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index c5ec89732a8d..9a2d1a04eb24 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -755,6 +755,13 @@ union bpf_attr {
* @addr: pointer to struct sockaddr to bind socket to
* @addr_len: length of sockaddr structure
* Return: 0 on success or negative error code
+ *
+ * int bpf_xdp_adjust_tail(xdp_md, delta)
+ * Adjust the xdp_md.data_end by delta. Only shrinking of packet's
+ * size is supported.
+ * @xdp_md: pointer to xdp_md
+ * @delta: A negative integer to be added to xdp_md.data_end
+ * Return: 0 on success or negative on error
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -821,7 +828,8 @@ union bpf_attr {
FN(msg_apply_bytes), \
FN(msg_cork_bytes), \
FN(msg_pull_data), \
- FN(bind),
+ FN(bind), \
+ FN(xdp_adjust_tail),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/net/core/filter.c b/net/core/filter.c
index a374b8560bc4..29318598fd60 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2725,6 +2725,30 @@ static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
.arg2_type = ARG_ANYTHING,
};
+BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
+{
+ void *data_end = xdp->data_end + offset;
+
+ /* only shrinking is allowed for now. */
+ if (unlikely(offset >= 0))
+ return -EINVAL;
+
+ if (unlikely(data_end < xdp->data + ETH_HLEN))
+ return -EINVAL;
+
+ xdp->data_end = data_end;
+
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
+ .func = bpf_xdp_adjust_tail,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+};
+
BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
{
void *meta = xdp->data_meta + offset;
@@ -3074,7 +3098,8 @@ bool bpf_helper_changes_pkt_data(void *func)
func == bpf_l4_csum_replace ||
func == bpf_xdp_adjust_head ||
func == bpf_xdp_adjust_meta ||
- func == bpf_msg_pull_data)
+ func == bpf_msg_pull_data ||
+ func == bpf_xdp_adjust_tail)
return true;
return false;
@@ -3888,6 +3913,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_xdp_redirect_proto;
case BPF_FUNC_redirect_map:
return &bpf_xdp_redirect_map_proto;
+ case BPF_FUNC_xdp_adjust_tail:
+ return &bpf_xdp_adjust_tail_proto;
default:
return bpf_base_func_proto(func_id);
}
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 01/11] bpf: adding bpf_xdp_adjust_tail helper Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 12:48 ` Jesper Dangaard Brouer
2018-04-18 4:29 ` [PATCH bpf-next v2 03/11] bpf: make mlx4 " Nikita V. Shirokov
` (9 subsequent siblings)
11 siblings, 1 reply; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, David S. Miller
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for generic XDP we need to reflect this packet's length change by
adjusting skb's tail pointer
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
net/core/dev.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 969462ebb296..11c789231a03 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3996,9 +3996,9 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
struct bpf_prog *xdp_prog)
{
struct netdev_rx_queue *rxqueue;
+ void *orig_data, *orig_data_end;
u32 metalen, act = XDP_DROP;
struct xdp_buff xdp;
- void *orig_data;
int hlen, off;
u32 mac_len;
@@ -4037,6 +4037,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
xdp.data_meta = xdp.data;
xdp.data_end = xdp.data + hlen;
xdp.data_hard_start = skb->data - skb_headroom(skb);
+ orig_data_end = xdp.data_end;
orig_data = xdp.data;
rxqueue = netif_get_rxqueue(skb);
@@ -4051,6 +4052,13 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
__skb_push(skb, -off);
skb->mac_header += off;
+ /* check if bpf_xdp_adjust_tail was used. it can only "shrink"
+ * pckt.
+ */
+ off = orig_data_end - xdp.data_end;
+ if (off != 0)
+ skb_set_tail_pointer(skb, xdp.data_end - xdp.data);
+
switch (act) {
case XDP_REDIRECT:
case XDP_TX:
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 ` [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail Nikita V. Shirokov
@ 2018-04-18 12:48 ` Jesper Dangaard Brouer
2018-04-18 4:48 ` Nikita V. Shirokov
0 siblings, 1 reply; 18+ messages in thread
From: Jesper Dangaard Brouer @ 2018-04-18 12:48 UTC (permalink / raw)
To: Nikita V. Shirokov
Cc: brouer, Alexei Starovoitov, Daniel Borkmann, David S. Miller ,
netdev
On Tue, 17 Apr 2018 21:29:42 -0700
"Nikita V. Shirokov" <tehnerd@tehnerd.com> wrote:
> w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
> well (only "decrease" of pointer's location is going to be supported).
> changing of this pointer will change packet's size.
> for generic XDP we need to reflect this packet's length change by
> adjusting skb's tail pointer
>
> Acked-by: Alexei Starovoitov <ast@kernel.org>
You are missing your own Signed-off-by: line on all of the patches.
BTW, thank you for working on this! It have been on my todo-list for a
while now!
_After_ this patchset, I would like to see adding support for
"increasing" the data_end location to create a larger packet. For that
we should likely add a data_hard_end pointer. This, would also be
helpful in cpu_map_build_skb() to know the data_hard_end, to determine
the frame size (as some driver doesn't use PAGE_SIZE frames, ixgbe).
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail
2018-04-18 12:48 ` Jesper Dangaard Brouer
@ 2018-04-18 4:48 ` Nikita V. Shirokov
0 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:48 UTC (permalink / raw)
To: Jesper Dangaard Brouer
Cc: Alexei Starovoitov, Daniel Borkmann, David S. Miller , netdev
On Wed, Apr 18, 2018 at 02:48:18PM +0200, Jesper Dangaard Brouer wrote:
> On Tue, 17 Apr 2018 21:29:42 -0700
> "Nikita V. Shirokov" <tehnerd@tehnerd.com> wrote:
>
> > w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
> > well (only "decrease" of pointer's location is going to be supported).
> > changing of this pointer will change packet's size.
> > for generic XDP we need to reflect this packet's length change by
> > adjusting skb's tail pointer
> >
> > Acked-by: Alexei Starovoitov <ast@kernel.org>
>
> You are missing your own Signed-off-by: line on all of the patches.
>
yeah, somehow lost it between v1 and v2 :) thanks !
> BTW, thank you for working on this! It have been on my todo-list for a
> while now!
>
> _After_ this patchset, I would like to see adding support for
> "increasing" the data_end location to create a larger packet. For that
> we should likely add a data_hard_end pointer. This, would also be
> helpful in cpu_map_build_skb() to know the data_hard_end, to determine
> the frame size (as some driver doesn't use PAGE_SIZE frames, ixgbe).
>
yeah, increasing the size would be nice to have, but will require more
thinking / rework on drivers side (as you pointed out it's not as easy
as "every driver have at least PAGE_SIZE of data available for xdp".).
will add to my TODO
>
> --
> Best regards,
> Jesper Dangaard Brouer
> MSc.CS, Principal Kernel Engineer at Red Hat
> LinkedIn: http://www.linkedin.com/in/brouer
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH bpf-next v2 03/11] bpf: make mlx4 compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 01/11] bpf: adding bpf_xdp_adjust_tail helper Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 02/11] bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 10:53 ` Tariq Toukan
2018-04-18 4:29 ` [PATCH bpf-next v2 04/11] bpf: make bnxt " Nikita V. Shirokov
` (8 subsequent siblings)
11 siblings, 1 reply; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Tariq Toukan
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for mlx4 driver we will just calculate packet's length unconditionally
(the same way as it's already being done in mlx5)
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 5c613c6663da..efc55feddc5c 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -775,8 +775,8 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
act = bpf_prog_run_xdp(xdp_prog, &xdp);
+ length = xdp.data_end - xdp.data;
if (xdp.data != orig_data) {
- length = xdp.data_end - xdp.data;
frags[0].page_offset = xdp.data -
xdp.data_hard_start;
va = xdp.data;
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH bpf-next v2 03/11] bpf: make mlx4 compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 ` [PATCH bpf-next v2 03/11] bpf: make mlx4 " Nikita V. Shirokov
@ 2018-04-18 10:53 ` Tariq Toukan
0 siblings, 0 replies; 18+ messages in thread
From: Tariq Toukan @ 2018-04-18 10:53 UTC (permalink / raw)
To: Nikita V. Shirokov, Alexei Starovoitov, Daniel Borkmann,
Tariq Toukan
Cc: netdev
On 18/04/2018 7:29 AM, Nikita V. Shirokov wrote:
> w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
> well (only "decrease" of pointer's location is going to be supported).
> changing of this pointer will change packet's size.
> for mlx4 driver we will just calculate packet's length unconditionally
> (the same way as it's already being done in mlx5)
>
> Acked-by: Alexei Starovoitov <ast@kernel.org>
> ---
> drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> index 5c613c6663da..efc55feddc5c 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
> @@ -775,8 +775,8 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
>
> act = bpf_prog_run_xdp(xdp_prog, &xdp);
>
> + length = xdp.data_end - xdp.data;
> if (xdp.data != orig_data) {
> - length = xdp.data_end - xdp.data;
> frags[0].page_offset = xdp.data -
> xdp.data_hard_start;
> va = xdp.data;
>
Acked-by: Tariq Toukan <tariqt@mellanox.com>
Thanks.
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH bpf-next v2 04/11] bpf: make bnxt compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (2 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 03/11] bpf: make mlx4 " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 05/11] bpf: make cavium thunder " Nikita V. Shirokov
` (7 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Michael Chan
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for bnxt driver we will just calculate packet's length unconditionally
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 1389ab5e05df..1f0e872d0667 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -113,10 +113,10 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
if (tx_avail != bp->tx_ring_size)
*event &= ~BNXT_RX_EVENT;
+ *len = xdp.data_end - xdp.data;
if (orig_data != xdp.data) {
offset = xdp.data - xdp.data_hard_start;
*data_ptr = xdp.data_hard_start + offset;
- *len = xdp.data_end - xdp.data;
}
switch (act) {
case XDP_PASS:
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 05/11] bpf: make cavium thunder compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (3 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 04/11] bpf: make bnxt " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 06/11] bpf: make netronome nfp " Nikita V. Shirokov
` (6 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Robert Richter,
Sunil Goutham
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for cavium's thunder driver we will just calculate packet's length
unconditionally
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
drivers/net/ethernet/cavium/thunder/nicvf_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
index 707db3304396..7135db45927e 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
@@ -538,9 +538,9 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
action = bpf_prog_run_xdp(prog, &xdp);
rcu_read_unlock();
+ len = xdp.data_end - xdp.data;
/* Check if XDP program has changed headers */
if (orig_data != xdp.data) {
- len = xdp.data_end - xdp.data;
offset = orig_data - xdp.data;
dma_addr -= offset;
}
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 06/11] bpf: make netronome nfp compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (4 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 05/11] bpf: make cavium thunder " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 07/11] bpf: make tun " Nikita V. Shirokov
` (5 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Jakub Kicinski
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for nfp driver we will just calculate packet's length unconditionally
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 1eb6549f2a54..d9111c077699 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1722,7 +1722,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
act = bpf_prog_run_xdp(xdp_prog, &xdp);
- pkt_len -= xdp.data - orig_data;
+ pkt_len = xdp.data_end - xdp.data;
pkt_off += xdp.data - orig_data;
switch (act) {
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 07/11] bpf: make tun compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (5 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 06/11] bpf: make netronome nfp " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 08/11] bpf: make virtio " Nikita V. Shirokov
` (4 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Jason Wang, David S. Miller,
Michael S. Tsirkin
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for tun driver we need to adjust XDP_PASS handling by recalculating
length of the packet if it was passed to the TCP/IP stack
(in case if after xdp's prog run data_end pointer was adjusted)
Reviewed-by: Jason Wang <jasowang@redhat.com>
---
drivers/net/tun.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 1e58be152d5c..901351a6ed21 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1696,6 +1696,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
return NULL;
case XDP_PASS:
delta = orig_data - xdp.data;
+ len = xdp.data_end - xdp.data;
break;
default:
bpf_warn_invalid_xdp_action(act);
@@ -1716,7 +1717,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
}
skb_reserve(skb, pad - delta);
- skb_put(skb, len + delta);
+ skb_put(skb, len);
get_page(alloc_frag->page);
alloc_frag->offset += buflen;
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 08/11] bpf: make virtio compatible w/ bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (6 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 07/11] bpf: make tun " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 09/11] bpf: making bpf_prog_test run aware of possible data_end ptr change Nikita V. Shirokov
` (3 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann,
Michael S. Tsirkin mst @ redhat . com , Jason Wang
Cc: netdev, Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for virtio driver we need to adjust XDP_PASS handling by recalculating
length of the packet if it was passed to the TCP/IP stack
Reviewed-by: Jason Wang <jasowang@redhat.com>
---
drivers/net/virtio_net.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 01694e26f03e..779a4f798522 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -606,6 +606,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
case XDP_PASS:
/* Recalculate length in case bpf program changed it */
delta = orig_data - xdp.data;
+ len = xdp.data_end - xdp.data;
break;
case XDP_TX:
xdpf = convert_to_xdp_frame(&xdp);
@@ -642,7 +643,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
goto err;
}
skb_reserve(skb, headroom - delta);
- skb_put(skb, len + delta);
+ skb_put(skb, len);
if (!delta) {
buf += header_offset;
memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
@@ -757,6 +758,10 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
offset = xdp.data -
page_address(xdp_page) - vi->hdr_len;
+ /* recalculate len if xdp.data or xdp.data_end were
+ * adjusted
+ */
+ len = xdp.data_end - xdp.data;
/* We can only create skb based on xdp_page. */
if (unlikely(xdp_page != page)) {
rcu_read_unlock();
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 09/11] bpf: making bpf_prog_test run aware of possible data_end ptr change
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (7 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 08/11] bpf: make virtio " Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 10/11] bpf: adding tests for bpf_xdp_adjust_tail Nikita V. Shirokov
` (2 subsequent siblings)
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann; +Cc: netdev, Nikita V. Shirokov
after introduction of bpf_xdp_adjust_tail helper packet length
could be changed not only if xdp->data pointer has been changed
but xdp->data_end as well. making bpf_prog_test_run aware of this
possibility
---
net/bpf/test_run.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 2ced48662c1f..68c3578343b4 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -170,7 +170,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
xdp.rxq = &rxqueue->xdp_rxq;
retval = bpf_test_run(prog, &xdp, repeat, &duration);
- if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN)
+ if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN ||
+ xdp.data_end != xdp.data + size)
size = xdp.data_end - xdp.data;
ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration);
kfree(data);
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 10/11] bpf: adding tests for bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (8 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 09/11] bpf: making bpf_prog_test run aware of possible data_end ptr change Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 4:29 ` [PATCH bpf-next v2 11/11] bpf: add bpf_xdp_adjust_tail sample prog Nikita V. Shirokov
2018-04-18 12:37 ` [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Daniel Borkmann
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann; +Cc: netdev, Nikita V. Shirokov
adding selftests for bpf_xdp_adjust_tail helper. in this synthetic test
we are testing that 1) if data_end < data helper will return EINVAL
2) for normal use case packet's length would be reduced.
---
tools/include/uapi/linux/bpf.h | 10 +++++++-
tools/testing/selftests/bpf/Makefile | 2 +-
tools/testing/selftests/bpf/bpf_helpers.h | 3 +++
tools/testing/selftests/bpf/test_adjust_tail.c | 30 ++++++++++++++++++++++++
tools/testing/selftests/bpf/test_progs.c | 32 ++++++++++++++++++++++++++
5 files changed, 75 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/bpf/test_adjust_tail.c
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 9d07465023a2..56bf493ba7ed 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -755,6 +755,13 @@ union bpf_attr {
* @addr: pointer to struct sockaddr to bind socket to
* @addr_len: length of sockaddr structure
* Return: 0 on success or negative error code
+ *
+ * int bpf_xdp_adjust_tail(xdp_md, delta)
+ * Adjust the xdp_md.data_end by delta. Only shrinking of packet's
+ * size is supported.
+ * @xdp_md: pointer to xdp_md
+ * @delta: A negative integer to be added to xdp_md.data_end
+ * Return: 0 on success or negative on error
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -821,7 +828,8 @@ union bpf_attr {
FN(msg_apply_bytes), \
FN(msg_cork_bytes), \
FN(msg_pull_data), \
- FN(bind),
+ FN(bind), \
+ FN(xdp_adjust_tail),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 0a315ddabbf4..3e819dc70bee 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -31,7 +31,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \
test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \
sample_map_ret0.o test_tcpbpf_kern.o test_stacktrace_build_id.o \
- sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o
+ sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o
# Order correspond to 'make run_tests' order
TEST_PROGS := test_kmod.sh \
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index d8223d99f96d..50c607014b22 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -96,6 +96,9 @@ static int (*bpf_msg_pull_data)(void *ctx, int start, int end, int flags) =
(void *) BPF_FUNC_msg_pull_data;
static int (*bpf_bind)(void *ctx, void *addr, int addr_len) =
(void *) BPF_FUNC_bind;
+static int (*bpf_xdp_adjust_tail)(void *ctx, int offset) =
+ (void *) BPF_FUNC_xdp_adjust_tail;
+
/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
diff --git a/tools/testing/selftests/bpf/test_adjust_tail.c b/tools/testing/selftests/bpf/test_adjust_tail.c
new file mode 100644
index 000000000000..4cd5e860c903
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_adjust_tail.c
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * Copyright (c) 2018 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include "bpf_helpers.h"
+
+int _version SEC("version") = 1;
+
+SEC("xdp_adjust_tail")
+int _xdp_adjust_tail(struct xdp_md *xdp)
+{
+ void *data_end = (void *)(long)xdp->data_end;
+ void *data = (void *)(long)xdp->data;
+ int offset = 0;
+
+ if (data_end - data == 54)
+ offset = 256;
+ else
+ offset = 20;
+ if (bpf_xdp_adjust_tail(xdp, 0 - offset))
+ return XDP_DROP;
+ return XDP_TX;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index faadbe233966..eedda98d7bb1 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -166,6 +166,37 @@ static void test_xdp(void)
bpf_object__close(obj);
}
+static void test_xdp_adjust_tail(void)
+{
+ const char *file = "./test_adjust_tail.o";
+ struct bpf_object *obj;
+ char buf[128];
+ __u32 duration, retval, size;
+ int err, prog_fd;
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
+ if (err) {
+ error_cnt++;
+ return;
+ }
+
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
+ buf, &size, &retval, &duration);
+
+ CHECK(err || errno || retval != XDP_DROP,
+ "ipv4", "err %d errno %d retval %d size %d\n",
+ err, errno, retval, size);
+
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v6, sizeof(pkt_v6),
+ buf, &size, &retval, &duration);
+ CHECK(err || errno || retval != XDP_TX || size != 54,
+ "ipv6", "err %d errno %d retval %d size %d\n",
+ err, errno, retval, size);
+ bpf_object__close(obj);
+}
+
+
+
#define MAGIC_VAL 0x1234
#define NUM_ITER 100000
#define VIP_NUM 5
@@ -1177,6 +1208,7 @@ int main(void)
{
test_pkt_access();
test_xdp();
+ test_xdp_adjust_tail();
test_l4lb_all();
test_xdp_noinline();
test_tcp_estats();
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* [PATCH bpf-next v2 11/11] bpf: add bpf_xdp_adjust_tail sample prog
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (9 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 10/11] bpf: adding tests for bpf_xdp_adjust_tail Nikita V. Shirokov
@ 2018-04-18 4:29 ` Nikita V. Shirokov
2018-04-18 12:37 ` [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Daniel Borkmann
11 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:29 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann; +Cc: netdev, Nikita V. Shirokov
adding bpf's sample program which is using bpf_xdp_adjust_tail helper
by generating ICMPv4 "packet to big" message if ingress packet's size is
bigger then 600 bytes
---
samples/bpf/Makefile | 4 +
samples/bpf/xdp_adjust_tail_kern.c | 152 ++++++++++++++++++++++++++++++
samples/bpf/xdp_adjust_tail_user.c | 142 ++++++++++++++++++++++++++++
tools/testing/selftests/bpf/bpf_helpers.h | 2 +
4 files changed, 300 insertions(+)
create mode 100644 samples/bpf/xdp_adjust_tail_kern.c
create mode 100644 samples/bpf/xdp_adjust_tail_user.c
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 4d6a6edd4bf6..aa8c392e2e52 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -44,6 +44,7 @@ hostprogs-y += xdp_monitor
hostprogs-y += xdp_rxq_info
hostprogs-y += syscall_tp
hostprogs-y += cpustat
+hostprogs-y += xdp_adjust_tail
# Libbpf dependencies
LIBBPF := ../../tools/lib/bpf/bpf.o ../../tools/lib/bpf/nlattr.o
@@ -95,6 +96,7 @@ xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o
xdp_rxq_info-objs := bpf_load.o $(LIBBPF) xdp_rxq_info_user.o
syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o
cpustat-objs := bpf_load.o $(LIBBPF) cpustat_user.o
+xdp_adjust_tail-objs := bpf_load.o $(LIBBPF) xdp_adjust_tail_user.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
@@ -148,6 +150,7 @@ always += xdp_rxq_info_kern.o
always += xdp2skb_meta_kern.o
always += syscall_tp_kern.o
always += cpustat_kern.o
+always += xdp_adjust_tail_kern.o
HOSTCFLAGS += -I$(objtree)/usr/include
HOSTCFLAGS += -I$(srctree)/tools/lib/
@@ -193,6 +196,7 @@ HOSTLOADLIBES_xdp_monitor += -lelf
HOSTLOADLIBES_xdp_rxq_info += -lelf
HOSTLOADLIBES_syscall_tp += -lelf
HOSTLOADLIBES_cpustat += -lelf
+HOSTLOADLIBES_xdp_adjust_tail += -lelf
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
diff --git a/samples/bpf/xdp_adjust_tail_kern.c b/samples/bpf/xdp_adjust_tail_kern.c
new file mode 100644
index 000000000000..411fdb21f8bc
--- /dev/null
+++ b/samples/bpf/xdp_adjust_tail_kern.c
@@ -0,0 +1,152 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * Copyright (c) 2018 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program shows how to use bpf_xdp_adjust_tail() by
+ * generating ICMPv4 "packet to big" (unreachable/ df bit set frag needed
+ * to be more preice in case of v4)" where receiving packets bigger then
+ * 600 bytes.
+ */
+#define KBUILD_MODNAME "foo"
+#include <uapi/linux/bpf.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/icmp.h>
+#include "bpf_helpers.h"
+
+#define DEFAULT_TTL 64
+#define MAX_PCKT_SIZE 600
+#define ICMP_TOOBIG_SIZE 98
+#define ICMP_TOOBIG_PAYLOAD_SIZE 92
+
+struct bpf_map_def SEC("maps") icmpcnt = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(__u32),
+ .value_size = sizeof(__u64),
+ .max_entries = 1,
+};
+
+static __always_inline void count_icmp(void)
+{
+ u64 key = 0;
+ u64 *icmp_count;
+
+ icmp_count = bpf_map_lookup_elem(&icmpcnt, &key);
+ if (icmp_count)
+ *icmp_count += 1;
+}
+
+static __always_inline void swap_mac(void *data, struct ethhdr *orig_eth)
+{
+ struct ethhdr *eth;
+
+ eth = data;
+ memcpy(eth->h_source, orig_eth->h_dest, ETH_ALEN);
+ memcpy(eth->h_dest, orig_eth->h_source, ETH_ALEN);
+ eth->h_proto = orig_eth->h_proto;
+}
+
+static __always_inline __u16 csum_fold_helper(__u32 csum)
+{
+ return ~((csum & 0xffff) + (csum >> 16));
+}
+
+static __always_inline void ipv4_csum(void *data_start, int data_size,
+ __u32 *csum)
+{
+ *csum = bpf_csum_diff(0, 0, data_start, data_size, *csum);
+ *csum = csum_fold_helper(*csum);
+}
+
+static __always_inline int send_icmp4_too_big(struct xdp_md *xdp)
+{
+ int headroom = (int)sizeof(struct iphdr) + (int)sizeof(struct icmphdr);
+
+ if (bpf_xdp_adjust_head(xdp, 0 - headroom))
+ return XDP_DROP;
+ void *data = (void *)(long)xdp->data;
+ void *data_end = (void *)(long)xdp->data_end;
+
+ if (data + (ICMP_TOOBIG_SIZE + headroom) > data_end)
+ return XDP_DROP;
+
+ struct iphdr *iph, *orig_iph;
+ struct icmphdr *icmp_hdr;
+ struct ethhdr *orig_eth;
+ __u32 csum = 0;
+ __u64 off = 0;
+
+ orig_eth = data + headroom;
+ swap_mac(data, orig_eth);
+ off += sizeof(struct ethhdr);
+ iph = data + off;
+ off += sizeof(struct iphdr);
+ icmp_hdr = data + off;
+ off += sizeof(struct icmphdr);
+ orig_iph = data + off;
+ icmp_hdr->type = ICMP_DEST_UNREACH;
+ icmp_hdr->code = ICMP_FRAG_NEEDED;
+ icmp_hdr->un.frag.mtu = htons(MAX_PCKT_SIZE-sizeof(struct ethhdr));
+ icmp_hdr->checksum = 0;
+ ipv4_csum(icmp_hdr, ICMP_TOOBIG_PAYLOAD_SIZE, &csum);
+ icmp_hdr->checksum = csum;
+ iph->ttl = DEFAULT_TTL;
+ iph->daddr = orig_iph->saddr;
+ iph->saddr = orig_iph->daddr;
+ iph->version = 4;
+ iph->ihl = 5;
+ iph->protocol = IPPROTO_ICMP;
+ iph->tos = 0;
+ iph->tot_len = htons(
+ ICMP_TOOBIG_SIZE + headroom - sizeof(struct ethhdr));
+ iph->check = 0;
+ csum = 0;
+ ipv4_csum(iph, sizeof(struct iphdr), &csum);
+ iph->check = csum;
+ count_icmp();
+ return XDP_TX;
+}
+
+
+static __always_inline int handle_ipv4(struct xdp_md *xdp)
+{
+ void *data_end = (void *)(long)xdp->data_end;
+ void *data = (void *)(long)xdp->data;
+ int pckt_size = data_end - data;
+ int offset;
+
+ if (pckt_size > MAX_PCKT_SIZE) {
+ offset = pckt_size - ICMP_TOOBIG_SIZE;
+ if (bpf_xdp_adjust_tail(xdp, 0 - offset))
+ return XDP_PASS;
+ return send_icmp4_too_big(xdp);
+ }
+ return XDP_PASS;
+}
+
+SEC("xdp_icmp")
+int _xdp_icmp(struct xdp_md *xdp)
+{
+ void *data_end = (void *)(long)xdp->data_end;
+ void *data = (void *)(long)xdp->data;
+ struct ethhdr *eth = data;
+ __u16 h_proto;
+
+ if (eth + 1 > data_end)
+ return XDP_DROP;
+
+ h_proto = eth->h_proto;
+
+ if (h_proto == htons(ETH_P_IP))
+ return handle_ipv4(xdp);
+ else
+ return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c
new file mode 100644
index 000000000000..f621a541b574
--- /dev/null
+++ b/samples/bpf/xdp_adjust_tail_user.c
@@ -0,0 +1,142 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * Copyright (c) 2018 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/bpf.h>
+#include <linux/if_link.h>
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+#include <arpa/inet.h>
+#include <netinet/ether.h>
+#include <unistd.h>
+#include <time.h>
+#include "bpf_load.h"
+#include "libbpf.h"
+#include "bpf_util.h"
+
+#define STATS_INTERVAL_S 2U
+
+static int ifindex = -1;
+static __u32 xdp_flags;
+
+static void int_exit(int sig)
+{
+ if (ifindex > -1)
+ bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
+ exit(0);
+}
+
+/* simple "icmp packet too big sent" counter
+ */
+static void poll_stats(unsigned int kill_after_s)
+{
+ time_t started_at = time(NULL);
+ __u64 value = 0;
+ int key = 0;
+
+
+ while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
+ sleep(STATS_INTERVAL_S);
+
+ assert(bpf_map_lookup_elem(map_fd[0], &key, &value) == 0);
+
+ printf("icmp \"packet too big\" sent: %10llu pkts\n", value);
+ }
+}
+
+static void usage(const char *cmd)
+{
+ printf("Start a XDP prog which send ICMP \"packet too big\" \n"
+ "messages if ingress packet is bigger then MAX_SIZE bytes\n");
+ printf("Usage: %s [...]\n", cmd);
+ printf(" -i <ifindex> Interface Index\n");
+ printf(" -T <stop-after-X-seconds> Default: 0 (forever)\n");
+ printf(" -S use skb-mode\n");
+ printf(" -N enforce native mode\n");
+ printf(" -h Display this help\n");
+}
+
+int main(int argc, char **argv)
+{
+ unsigned char opt_flags[256] = {};
+ unsigned int kill_after_s = 0;
+ const char *optstr = "i:T:SNh";
+ struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+ char filename[256];
+ int opt;
+ int i;
+
+
+ for (i = 0; i < strlen(optstr); i++)
+ if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
+ opt_flags[(unsigned char)optstr[i]] = 1;
+
+ while ((opt = getopt(argc, argv, optstr)) != -1) {
+
+ switch (opt) {
+ case 'i':
+ ifindex = atoi(optarg);
+ break;
+ case 'T':
+ kill_after_s = atoi(optarg);
+ break;
+ case 'S':
+ xdp_flags |= XDP_FLAGS_SKB_MODE;
+ break;
+ case 'N':
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+ break;
+ default:
+ usage(argv[0]);
+ return 1;
+ }
+ opt_flags[opt] = 0;
+ }
+
+ for (i = 0; i < strlen(optstr); i++) {
+ if (opt_flags[(unsigned int)optstr[i]]) {
+ fprintf(stderr, "Missing argument -%c\n", optstr[i]);
+ usage(argv[0]);
+ return 1;
+ }
+ }
+
+ if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+ perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
+ return 1;
+ }
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+ if (load_bpf_file(filename)) {
+ printf("%s", bpf_log_buf);
+ return 1;
+ }
+
+ if (!prog_fd[0]) {
+ printf("load_bpf_file: %s\n", strerror(errno));
+ return 1;
+ }
+
+ signal(SIGINT, int_exit);
+ signal(SIGTERM, int_exit);
+
+ if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
+ printf("link set xdp fd failed\n");
+ return 1;
+ }
+
+ poll_stats(kill_after_s);
+
+ bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 50c607014b22..9271576bdc8f 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -132,6 +132,8 @@ static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flag
(void *) BPF_FUNC_l3_csum_replace;
static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
(void *) BPF_FUNC_l4_csum_replace;
+static int (*bpf_csum_diff)(void *from, int from_size, void *to, int to_size, int seed) =
+ (void *) BPF_FUNC_csum_diff;
static int (*bpf_skb_under_cgroup)(void *ctx, void *map, int index) =
(void *) BPF_FUNC_skb_under_cgroup;
static int (*bpf_skb_change_head)(void *, int len, int flags) =
--
2.15.1
^ permalink raw reply related [flat|nested] 18+ messages in thread* Re: [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail
2018-04-18 4:29 [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Nikita V. Shirokov
` (10 preceding siblings ...)
2018-04-18 4:29 ` [PATCH bpf-next v2 11/11] bpf: add bpf_xdp_adjust_tail sample prog Nikita V. Shirokov
@ 2018-04-18 12:37 ` Daniel Borkmann
2018-04-18 4:44 ` Nikita V. Shirokov
11 siblings, 1 reply; 18+ messages in thread
From: Daniel Borkmann @ 2018-04-18 12:37 UTC (permalink / raw)
To: Nikita V. Shirokov, Alexei Starovoitov; +Cc: netdev
On 04/18/2018 06:29 AM, Nikita V. Shirokov wrote:
> In this patch series i'm add new bpf helper which allow to manupulate
> xdp's data_end pointer. right now only "shrinking" (reduce packet's size
> by moving pointer) is supported (and i see no use case for "growing").
> Main use case for such helper is to be able to generate controll (ICMP)
> messages from XDP context. such messages usually contains first N bytes
> from original packets as a payload, and this is exactly what this helper
> would allow us to do (see patch 3 for sample program, where we generate
> ICMP "packet too big" message). This helper could be usefull for load
> balancing applications where after additional encapsulation, resulting
> packet could be bigger then interface MTU.
> Aside from new helper this patch series contains minor changes in device
> drivers (for ones which requires), so they would recal packet's length
> not only when head pointer was adjusted, but if tail's one as well.
The whole set doesn't have any SoBs from you which is mandatory before
applying anything. Please add.
Thanks,
Daniel
> v1->v2:
> * fixed kbuild warning
> * made offset eq 0 invalid for xdp_bpf_adjust_tail
> * splitted bpf_prog_test_run fix and selftests in sep commits
> * added SPDX licence where applicable
> * some reshuffling in patches order (tests now in the end)
>
>
> Nikita V. Shirokov (11):
> bpf: making bpf_prog_test run aware of possible data_end ptr change
> bpf: adding tests for bpf_xdp_adjust_tail
> bpf: adding bpf_xdp_adjust_tail helper
> bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail
> bpf: make mlx4 compatible w/ bpf_xdp_adjust_tail
> bpf: make bnxt compatible w/ bpf_xdp_adjust_tail
> bpf: make cavium thunder compatible w/ bpf_xdp_adjust_tail
> bpf: make netronome nfp compatible w/ bpf_xdp_adjust_tail
> bpf: make tun compatible w/ bpf_xdp_adjust_tail
> bpf: make virtio compatible w/ bpf_xdp_adjust_tail
> bpf: add bpf_xdp_adjust_tail sample prog
>
> drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 2 +-
> drivers/net/ethernet/cavium/thunder/nicvf_main.c | 2 +-
> drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +-
> .../net/ethernet/netronome/nfp/nfp_net_common.c | 2 +-
> drivers/net/tun.c | 3 +-
> drivers/net/virtio_net.c | 7 +-
> include/uapi/linux/bpf.h | 10 +-
> net/bpf/test_run.c | 3 +-
> net/core/dev.c | 10 +-
> net/core/filter.c | 29 +++-
> samples/bpf/Makefile | 4 +
> samples/bpf/xdp_adjust_tail_kern.c | 152 +++++++++++++++++++++
> samples/bpf/xdp_adjust_tail_user.c | 142 +++++++++++++++++++
> tools/include/uapi/linux/bpf.h | 10 +-
> tools/testing/selftests/bpf/Makefile | 2 +-
> tools/testing/selftests/bpf/bpf_helpers.h | 5 +
> tools/testing/selftests/bpf/test_adjust_tail.c | 30 ++++
> tools/testing/selftests/bpf/test_progs.c | 32 +++++
> 18 files changed, 435 insertions(+), 12 deletions(-)
> create mode 100644 samples/bpf/xdp_adjust_tail_kern.c
> create mode 100644 samples/bpf/xdp_adjust_tail_user.c
> create mode 100644 tools/testing/selftests/bpf/test_adjust_tail.c
>
^ permalink raw reply [flat|nested] 18+ messages in thread* Re: [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail
2018-04-18 12:37 ` [PATCH bpf-next v2 00/11] introduction of bpf_xdp_adjust_tail Daniel Borkmann
@ 2018-04-18 4:44 ` Nikita V. Shirokov
0 siblings, 0 replies; 18+ messages in thread
From: Nikita V. Shirokov @ 2018-04-18 4:44 UTC (permalink / raw)
To: Daniel Borkmann; +Cc: Alexei Starovoitov, netdev
On Wed, Apr 18, 2018 at 02:37:40PM +0200, Daniel Borkmann wrote:
> On 04/18/2018 06:29 AM, Nikita V. Shirokov wrote:
> > In this patch series i'm add new bpf helper which allow to manupulate
> > xdp's data_end pointer. right now only "shrinking" (reduce packet's size
> > by moving pointer) is supported (and i see no use case for "growing").
> > Main use case for such helper is to be able to generate controll (ICMP)
> > messages from XDP context. such messages usually contains first N bytes
> > from original packets as a payload, and this is exactly what this helper
> > would allow us to do (see patch 3 for sample program, where we generate
> > ICMP "packet too big" message). This helper could be usefull for load
> > balancing applications where after additional encapsulation, resulting
> > packet could be bigger then interface MTU.
> > Aside from new helper this patch series contains minor changes in device
> > drivers (for ones which requires), so they would recal packet's length
> > not only when head pointer was adjusted, but if tail's one as well.
>
> The whole set doesn't have any SoBs from you which is mandatory before
> applying anything. Please add.
>
sorry about that, somehow lost it between v1 and v2 ;)
> Thanks,
> Daniel
>
> > v1->v2:
> > * fixed kbuild warning
> > * made offset eq 0 invalid for xdp_bpf_adjust_tail
> > * splitted bpf_prog_test_run fix and selftests in sep commits
> > * added SPDX licence where applicable
> > * some reshuffling in patches order (tests now in the end)
> >
> >
> > Nikita V. Shirokov (11):
> > bpf: making bpf_prog_test run aware of possible data_end ptr change
> > bpf: adding tests for bpf_xdp_adjust_tail
> > bpf: adding bpf_xdp_adjust_tail helper
> > bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail
> > bpf: make mlx4 compatible w/ bpf_xdp_adjust_tail
> > bpf: make bnxt compatible w/ bpf_xdp_adjust_tail
> > bpf: make cavium thunder compatible w/ bpf_xdp_adjust_tail
> > bpf: make netronome nfp compatible w/ bpf_xdp_adjust_tail
> > bpf: make tun compatible w/ bpf_xdp_adjust_tail
> > bpf: make virtio compatible w/ bpf_xdp_adjust_tail
> > bpf: add bpf_xdp_adjust_tail sample prog
> >
> > drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 2 +-
> > drivers/net/ethernet/cavium/thunder/nicvf_main.c | 2 +-
> > drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +-
> > .../net/ethernet/netronome/nfp/nfp_net_common.c | 2 +-
> > drivers/net/tun.c | 3 +-
> > drivers/net/virtio_net.c | 7 +-
> > include/uapi/linux/bpf.h | 10 +-
> > net/bpf/test_run.c | 3 +-
> > net/core/dev.c | 10 +-
> > net/core/filter.c | 29 +++-
> > samples/bpf/Makefile | 4 +
> > samples/bpf/xdp_adjust_tail_kern.c | 152 +++++++++++++++++++++
> > samples/bpf/xdp_adjust_tail_user.c | 142 +++++++++++++++++++
> > tools/include/uapi/linux/bpf.h | 10 +-
> > tools/testing/selftests/bpf/Makefile | 2 +-
> > tools/testing/selftests/bpf/bpf_helpers.h | 5 +
> > tools/testing/selftests/bpf/test_adjust_tail.c | 30 ++++
> > tools/testing/selftests/bpf/test_progs.c | 32 +++++
> > 18 files changed, 435 insertions(+), 12 deletions(-)
> > create mode 100644 samples/bpf/xdp_adjust_tail_kern.c
> > create mode 100644 samples/bpf/xdp_adjust_tail_user.c
> > create mode 100644 tools/testing/selftests/bpf/test_adjust_tail.c
> >
>
^ permalink raw reply [flat|nested] 18+ messages in thread