bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
// SPDX-License-Identifier: GPL-2.0
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|
|
/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
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|
#include <linux/skmsg.h>
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|
|
#include <linux/skbuff.h>
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#include <linux/scatterlist.h>
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|
#include <net/sock.h>
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|
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#include <net/tcp.h>
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static bool sk_msg_try_coalesce_ok(struct sk_msg *msg, int elem_first_coalesce)
|
|
|
|
{
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|
|
if (msg->sg.end > msg->sg.start &&
|
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|
|
elem_first_coalesce < msg->sg.end)
|
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|
|
return true;
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|
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|
|
if (msg->sg.end < msg->sg.start &&
|
|
|
|
(elem_first_coalesce > msg->sg.start ||
|
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|
|
elem_first_coalesce < msg->sg.end))
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|
return true;
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return false;
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|
}
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|
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int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
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|
|
|
int elem_first_coalesce)
|
|
|
|
{
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|
|
|
struct page_frag *pfrag = sk_page_frag(sk);
|
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|
int ret = 0;
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len -= msg->sg.size;
|
|
|
|
while (len > 0) {
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|
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|
struct scatterlist *sge;
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|
|
u32 orig_offset;
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|
|
int use, i;
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|
if (!sk_page_frag_refill(sk, pfrag))
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|
return -ENOMEM;
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orig_offset = pfrag->offset;
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use = min_t(int, len, pfrag->size - orig_offset);
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|
|
if (!sk_wmem_schedule(sk, use))
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|
return -ENOMEM;
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i = msg->sg.end;
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sk_msg_iter_var_prev(i);
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sge = &msg->sg.data[i];
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if (sk_msg_try_coalesce_ok(msg, elem_first_coalesce) &&
|
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|
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sg_page(sge) == pfrag->page &&
|
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|
|
sge->offset + sge->length == orig_offset) {
|
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|
sge->length += use;
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|
|
} else {
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|
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if (sk_msg_full(msg)) {
|
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ret = -ENOSPC;
|
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|
|
break;
|
|
|
|
}
|
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|
sge = &msg->sg.data[msg->sg.end];
|
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|
sg_unmark_end(sge);
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|
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sg_set_page(sge, pfrag->page, use, orig_offset);
|
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|
get_page(pfrag->page);
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sk_msg_iter_next(msg, end);
|
|
|
|
}
|
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|
sk_mem_charge(sk, use);
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msg->sg.size += use;
|
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|
|
pfrag->offset += use;
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|
len -= use;
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|
|
|
}
|
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|
return ret;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_alloc);
|
|
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|
|
2018-10-12 18:45:59 -06:00
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|
int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
|
|
|
|
u32 off, u32 len)
|
|
|
|
{
|
|
|
|
int i = src->sg.start;
|
|
|
|
struct scatterlist *sge = sk_msg_elem(src, i);
|
2019-01-15 18:42:44 -07:00
|
|
|
struct scatterlist *sgd = NULL;
|
2018-10-12 18:45:59 -06:00
|
|
|
u32 sge_len, sge_off;
|
|
|
|
|
|
|
|
while (off) {
|
|
|
|
if (sge->length > off)
|
|
|
|
break;
|
|
|
|
off -= sge->length;
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
if (i == src->sg.end && off)
|
|
|
|
return -ENOSPC;
|
|
|
|
sge = sk_msg_elem(src, i);
|
|
|
|
}
|
|
|
|
|
|
|
|
while (len) {
|
|
|
|
sge_len = sge->length - off;
|
|
|
|
if (sge_len > len)
|
|
|
|
sge_len = len;
|
2019-01-15 18:42:44 -07:00
|
|
|
|
|
|
|
if (dst->sg.end)
|
|
|
|
sgd = sk_msg_elem(dst, dst->sg.end - 1);
|
|
|
|
|
|
|
|
if (sgd &&
|
|
|
|
(sg_page(sge) == sg_page(sgd)) &&
|
|
|
|
(sg_virt(sge) + off == sg_virt(sgd) + sgd->length)) {
|
|
|
|
sgd->length += sge_len;
|
|
|
|
dst->sg.size += sge_len;
|
|
|
|
} else if (!sk_msg_full(dst)) {
|
|
|
|
sge_off = sge->offset + off;
|
|
|
|
sk_msg_page_add(dst, sg_page(sge), sge_len, sge_off);
|
|
|
|
} else {
|
|
|
|
return -ENOSPC;
|
|
|
|
}
|
|
|
|
|
2018-10-12 18:45:59 -06:00
|
|
|
off = 0;
|
|
|
|
len -= sge_len;
|
|
|
|
sk_mem_charge(sk, sge_len);
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
if (i == src->sg.end && len)
|
|
|
|
return -ENOSPC;
|
|
|
|
sge = sk_msg_elem(src, i);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_clone);
|
|
|
|
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes)
|
|
|
|
{
|
|
|
|
int i = msg->sg.start;
|
|
|
|
|
|
|
|
do {
|
|
|
|
struct scatterlist *sge = sk_msg_elem(msg, i);
|
|
|
|
|
|
|
|
if (bytes < sge->length) {
|
|
|
|
sge->length -= bytes;
|
|
|
|
sge->offset += bytes;
|
|
|
|
sk_mem_uncharge(sk, bytes);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
sk_mem_uncharge(sk, sge->length);
|
|
|
|
bytes -= sge->length;
|
|
|
|
sge->length = 0;
|
|
|
|
sge->offset = 0;
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
} while (bytes && i != msg->sg.end);
|
|
|
|
msg->sg.start = i;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_return_zero);
|
|
|
|
|
|
|
|
void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes)
|
|
|
|
{
|
|
|
|
int i = msg->sg.start;
|
|
|
|
|
|
|
|
do {
|
|
|
|
struct scatterlist *sge = &msg->sg.data[i];
|
|
|
|
int uncharge = (bytes < sge->length) ? bytes : sge->length;
|
|
|
|
|
|
|
|
sk_mem_uncharge(sk, uncharge);
|
|
|
|
bytes -= uncharge;
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
} while (i != msg->sg.end);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_return);
|
|
|
|
|
|
|
|
static int sk_msg_free_elem(struct sock *sk, struct sk_msg *msg, u32 i,
|
|
|
|
bool charge)
|
|
|
|
{
|
|
|
|
struct scatterlist *sge = sk_msg_elem(msg, i);
|
|
|
|
u32 len = sge->length;
|
|
|
|
|
|
|
|
if (charge)
|
|
|
|
sk_mem_uncharge(sk, len);
|
|
|
|
if (!msg->skb)
|
|
|
|
put_page(sg_page(sge));
|
|
|
|
memset(sge, 0, sizeof(*sge));
|
|
|
|
return len;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i,
|
|
|
|
bool charge)
|
|
|
|
{
|
|
|
|
struct scatterlist *sge = sk_msg_elem(msg, i);
|
|
|
|
int freed = 0;
|
|
|
|
|
|
|
|
while (msg->sg.size) {
|
|
|
|
msg->sg.size -= sge->length;
|
|
|
|
freed += sk_msg_free_elem(sk, msg, i, charge);
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
sk_msg_check_to_free(msg, i, msg->sg.size);
|
|
|
|
sge = sk_msg_elem(msg, i);
|
|
|
|
}
|
|
|
|
if (msg->skb)
|
|
|
|
consume_skb(msg->skb);
|
|
|
|
sk_msg_init(msg);
|
|
|
|
return freed;
|
|
|
|
}
|
|
|
|
|
|
|
|
int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg)
|
|
|
|
{
|
|
|
|
return __sk_msg_free(sk, msg, msg->sg.start, false);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_free_nocharge);
|
|
|
|
|
|
|
|
int sk_msg_free(struct sock *sk, struct sk_msg *msg)
|
|
|
|
{
|
|
|
|
return __sk_msg_free(sk, msg, msg->sg.start, true);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_free);
|
|
|
|
|
|
|
|
static void __sk_msg_free_partial(struct sock *sk, struct sk_msg *msg,
|
|
|
|
u32 bytes, bool charge)
|
|
|
|
{
|
|
|
|
struct scatterlist *sge;
|
|
|
|
u32 i = msg->sg.start;
|
|
|
|
|
|
|
|
while (bytes) {
|
|
|
|
sge = sk_msg_elem(msg, i);
|
|
|
|
if (!sge->length)
|
|
|
|
break;
|
|
|
|
if (bytes < sge->length) {
|
|
|
|
if (charge)
|
|
|
|
sk_mem_uncharge(sk, bytes);
|
|
|
|
sge->length -= bytes;
|
|
|
|
sge->offset += bytes;
|
|
|
|
msg->sg.size -= bytes;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
msg->sg.size -= sge->length;
|
|
|
|
bytes -= sge->length;
|
|
|
|
sk_msg_free_elem(sk, msg, i, charge);
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
sk_msg_check_to_free(msg, i, bytes);
|
|
|
|
}
|
|
|
|
msg->sg.start = i;
|
|
|
|
}
|
|
|
|
|
|
|
|
void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes)
|
|
|
|
{
|
|
|
|
__sk_msg_free_partial(sk, msg, bytes, true);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_free_partial);
|
|
|
|
|
|
|
|
void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
|
|
|
|
u32 bytes)
|
|
|
|
{
|
|
|
|
__sk_msg_free_partial(sk, msg, bytes, false);
|
|
|
|
}
|
|
|
|
|
|
|
|
void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len)
|
|
|
|
{
|
|
|
|
int trim = msg->sg.size - len;
|
|
|
|
u32 i = msg->sg.end;
|
|
|
|
|
|
|
|
if (trim <= 0) {
|
|
|
|
WARN_ON(trim < 0);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
sk_msg_iter_var_prev(i);
|
|
|
|
msg->sg.size = len;
|
|
|
|
while (msg->sg.data[i].length &&
|
|
|
|
trim >= msg->sg.data[i].length) {
|
|
|
|
trim -= msg->sg.data[i].length;
|
|
|
|
sk_msg_free_elem(sk, msg, i, true);
|
|
|
|
sk_msg_iter_var_prev(i);
|
|
|
|
if (!trim)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
msg->sg.data[i].length -= trim;
|
|
|
|
sk_mem_uncharge(sk, trim);
|
|
|
|
out:
|
|
|
|
/* If we trim data before curr pointer update copybreak and current
|
|
|
|
* so that any future copy operations start at new copy location.
|
|
|
|
* However trimed data that has not yet been used in a copy op
|
|
|
|
* does not require an update.
|
|
|
|
*/
|
|
|
|
if (msg->sg.curr >= i) {
|
|
|
|
msg->sg.curr = i;
|
|
|
|
msg->sg.copybreak = msg->sg.data[i].length;
|
|
|
|
}
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
msg->sg.end = i;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_trim);
|
|
|
|
|
|
|
|
int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
|
|
|
|
struct sk_msg *msg, u32 bytes)
|
|
|
|
{
|
|
|
|
int i, maxpages, ret = 0, num_elems = sk_msg_elem_used(msg);
|
|
|
|
const int to_max_pages = MAX_MSG_FRAGS;
|
|
|
|
struct page *pages[MAX_MSG_FRAGS];
|
|
|
|
ssize_t orig, copied, use, offset;
|
|
|
|
|
|
|
|
orig = msg->sg.size;
|
|
|
|
while (bytes > 0) {
|
|
|
|
i = 0;
|
|
|
|
maxpages = to_max_pages - num_elems;
|
|
|
|
if (maxpages == 0) {
|
|
|
|
ret = -EFAULT;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
copied = iov_iter_get_pages(from, pages, bytes, maxpages,
|
|
|
|
&offset);
|
|
|
|
if (copied <= 0) {
|
|
|
|
ret = -EFAULT;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
iov_iter_advance(from, copied);
|
|
|
|
bytes -= copied;
|
|
|
|
msg->sg.size += copied;
|
|
|
|
|
|
|
|
while (copied) {
|
|
|
|
use = min_t(int, copied, PAGE_SIZE - offset);
|
|
|
|
sg_set_page(&msg->sg.data[msg->sg.end],
|
|
|
|
pages[i], use, offset);
|
|
|
|
sg_unmark_end(&msg->sg.data[msg->sg.end]);
|
|
|
|
sk_mem_charge(sk, use);
|
|
|
|
|
|
|
|
offset = 0;
|
|
|
|
copied -= use;
|
|
|
|
sk_msg_iter_next(msg, end);
|
|
|
|
num_elems++;
|
|
|
|
i++;
|
|
|
|
}
|
|
|
|
/* When zerocopy is mixed with sk_msg_*copy* operations we
|
|
|
|
* may have a copybreak set in this case clear and prefer
|
|
|
|
* zerocopy remainder when possible.
|
|
|
|
*/
|
|
|
|
msg->sg.copybreak = 0;
|
|
|
|
msg->sg.curr = msg->sg.end;
|
|
|
|
}
|
|
|
|
out:
|
|
|
|
/* Revert iov_iter updates, msg will need to use 'trim' later if it
|
|
|
|
* also needs to be cleared.
|
|
|
|
*/
|
|
|
|
if (ret)
|
|
|
|
iov_iter_revert(from, msg->sg.size - orig);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_zerocopy_from_iter);
|
|
|
|
|
|
|
|
int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
|
|
|
|
struct sk_msg *msg, u32 bytes)
|
|
|
|
{
|
|
|
|
int ret = -ENOSPC, i = msg->sg.curr;
|
|
|
|
struct scatterlist *sge;
|
|
|
|
u32 copy, buf_size;
|
|
|
|
void *to;
|
|
|
|
|
|
|
|
do {
|
|
|
|
sge = sk_msg_elem(msg, i);
|
|
|
|
/* This is possible if a trim operation shrunk the buffer */
|
|
|
|
if (msg->sg.copybreak >= sge->length) {
|
|
|
|
msg->sg.copybreak = 0;
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
if (i == msg->sg.end)
|
|
|
|
break;
|
|
|
|
sge = sk_msg_elem(msg, i);
|
|
|
|
}
|
|
|
|
|
|
|
|
buf_size = sge->length - msg->sg.copybreak;
|
|
|
|
copy = (buf_size > bytes) ? bytes : buf_size;
|
|
|
|
to = sg_virt(sge) + msg->sg.copybreak;
|
|
|
|
msg->sg.copybreak += copy;
|
|
|
|
if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY)
|
|
|
|
ret = copy_from_iter_nocache(to, copy, from);
|
|
|
|
else
|
|
|
|
ret = copy_from_iter(to, copy, from);
|
|
|
|
if (ret != copy) {
|
|
|
|
ret = -EFAULT;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
bytes -= copy;
|
|
|
|
if (!bytes)
|
|
|
|
break;
|
|
|
|
msg->sg.copybreak = 0;
|
|
|
|
sk_msg_iter_var_next(i);
|
|
|
|
} while (i != msg->sg.end);
|
|
|
|
out:
|
|
|
|
msg->sg.curr = i;
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_msg_memcopy_from_iter);
|
|
|
|
|
|
|
|
static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct sock *sk = psock->sk;
|
|
|
|
int copied = 0, num_sge;
|
|
|
|
struct sk_msg *msg;
|
|
|
|
|
|
|
|
msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC);
|
|
|
|
if (unlikely(!msg))
|
|
|
|
return -EAGAIN;
|
|
|
|
if (!sk_rmem_schedule(sk, skb, skb->len)) {
|
|
|
|
kfree(msg);
|
|
|
|
return -EAGAIN;
|
|
|
|
}
|
|
|
|
|
|
|
|
sk_msg_init(msg);
|
|
|
|
num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
|
|
|
|
if (unlikely(num_sge < 0)) {
|
|
|
|
kfree(msg);
|
|
|
|
return num_sge;
|
|
|
|
}
|
|
|
|
|
|
|
|
sk_mem_charge(sk, skb->len);
|
|
|
|
copied = skb->len;
|
|
|
|
msg->sg.start = 0;
|
|
|
|
msg->sg.end = num_sge == MAX_MSG_FRAGS ? 0 : num_sge;
|
|
|
|
msg->skb = skb;
|
|
|
|
|
|
|
|
sk_psock_queue_msg(psock, msg);
|
2018-12-20 12:35:33 -07:00
|
|
|
sk_psock_data_ready(sk, psock);
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
return copied;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
|
|
|
|
u32 off, u32 len, bool ingress)
|
|
|
|
{
|
|
|
|
if (ingress)
|
|
|
|
return sk_psock_skb_ingress(psock, skb);
|
|
|
|
else
|
|
|
|
return skb_send_sock_locked(psock->sk, skb, off, len);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_backlog(struct work_struct *work)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = container_of(work, struct sk_psock, work);
|
|
|
|
struct sk_psock_work_state *state = &psock->work_state;
|
|
|
|
struct sk_buff *skb;
|
|
|
|
bool ingress;
|
|
|
|
u32 len, off;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
/* Lock sock to avoid losing sk_socket during loop. */
|
|
|
|
lock_sock(psock->sk);
|
|
|
|
if (state->skb) {
|
|
|
|
skb = state->skb;
|
|
|
|
len = state->len;
|
|
|
|
off = state->off;
|
|
|
|
state->skb = NULL;
|
|
|
|
goto start;
|
|
|
|
}
|
|
|
|
|
|
|
|
while ((skb = skb_dequeue(&psock->ingress_skb))) {
|
|
|
|
len = skb->len;
|
|
|
|
off = 0;
|
|
|
|
start:
|
|
|
|
ingress = tcp_skb_bpf_ingress(skb);
|
|
|
|
do {
|
|
|
|
ret = -EIO;
|
|
|
|
if (likely(psock->sk->sk_socket))
|
|
|
|
ret = sk_psock_handle_skb(psock, skb, off,
|
|
|
|
len, ingress);
|
|
|
|
if (ret <= 0) {
|
|
|
|
if (ret == -EAGAIN) {
|
|
|
|
state->skb = skb;
|
|
|
|
state->len = len;
|
|
|
|
state->off = off;
|
|
|
|
goto end;
|
|
|
|
}
|
|
|
|
/* Hard errors break pipe and stop xmit. */
|
|
|
|
sk_psock_report_error(psock, ret ? -ret : EPIPE);
|
|
|
|
sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
|
|
|
|
kfree_skb(skb);
|
|
|
|
goto end;
|
|
|
|
}
|
|
|
|
off += ret;
|
|
|
|
len -= ret;
|
|
|
|
} while (len);
|
|
|
|
|
|
|
|
if (!ingress)
|
|
|
|
kfree_skb(skb);
|
|
|
|
}
|
|
|
|
end:
|
|
|
|
release_sock(psock->sk);
|
|
|
|
}
|
|
|
|
|
|
|
|
struct sk_psock *sk_psock_init(struct sock *sk, int node)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = kzalloc_node(sizeof(*psock),
|
|
|
|
GFP_ATOMIC | __GFP_NOWARN,
|
|
|
|
node);
|
|
|
|
if (!psock)
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
psock->sk = sk;
|
|
|
|
psock->eval = __SK_NONE;
|
|
|
|
|
|
|
|
INIT_LIST_HEAD(&psock->link);
|
|
|
|
spin_lock_init(&psock->link_lock);
|
|
|
|
|
|
|
|
INIT_WORK(&psock->work, sk_psock_backlog);
|
|
|
|
INIT_LIST_HEAD(&psock->ingress_msg);
|
|
|
|
skb_queue_head_init(&psock->ingress_skb);
|
|
|
|
|
|
|
|
sk_psock_set_state(psock, SK_PSOCK_TX_ENABLED);
|
|
|
|
refcount_set(&psock->refcnt, 1);
|
|
|
|
|
|
|
|
rcu_assign_sk_user_data(sk, psock);
|
|
|
|
sock_hold(sk);
|
|
|
|
|
|
|
|
return psock;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_psock_init);
|
|
|
|
|
|
|
|
struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
struct sk_psock_link *link;
|
|
|
|
|
|
|
|
spin_lock_bh(&psock->link_lock);
|
|
|
|
link = list_first_entry_or_null(&psock->link, struct sk_psock_link,
|
|
|
|
list);
|
|
|
|
if (link)
|
|
|
|
list_del(&link->list);
|
|
|
|
spin_unlock_bh(&psock->link_lock);
|
|
|
|
return link;
|
|
|
|
}
|
|
|
|
|
|
|
|
void __sk_psock_purge_ingress_msg(struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
struct sk_msg *msg, *tmp;
|
|
|
|
|
|
|
|
list_for_each_entry_safe(msg, tmp, &psock->ingress_msg, list) {
|
|
|
|
list_del(&msg->list);
|
|
|
|
sk_msg_free(psock->sk, msg);
|
|
|
|
kfree(msg);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_zap_ingress(struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
__skb_queue_purge(&psock->ingress_skb);
|
|
|
|
__sk_psock_purge_ingress_msg(psock);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_link_destroy(struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
struct sk_psock_link *link, *tmp;
|
|
|
|
|
|
|
|
list_for_each_entry_safe(link, tmp, &psock->link, list) {
|
|
|
|
list_del(&link->list);
|
|
|
|
sk_psock_free_link(link);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_destroy_deferred(struct work_struct *gc)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = container_of(gc, struct sk_psock, gc);
|
|
|
|
|
|
|
|
/* No sk_callback_lock since already detached. */
|
2019-03-07 03:35:43 -07:00
|
|
|
strp_stop(&psock->parser.strp);
|
2019-01-28 02:13:35 -07:00
|
|
|
strp_done(&psock->parser.strp);
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
|
|
|
|
cancel_work_sync(&psock->work);
|
|
|
|
|
|
|
|
psock_progs_drop(&psock->progs);
|
|
|
|
|
|
|
|
sk_psock_link_destroy(psock);
|
|
|
|
sk_psock_cork_free(psock);
|
|
|
|
sk_psock_zap_ingress(psock);
|
|
|
|
|
|
|
|
if (psock->sk_redir)
|
|
|
|
sock_put(psock->sk_redir);
|
|
|
|
sock_put(psock->sk);
|
|
|
|
kfree(psock);
|
|
|
|
}
|
|
|
|
|
|
|
|
void sk_psock_destroy(struct rcu_head *rcu)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = container_of(rcu, struct sk_psock, rcu);
|
|
|
|
|
|
|
|
INIT_WORK(&psock->gc, sk_psock_destroy_deferred);
|
|
|
|
schedule_work(&psock->gc);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_psock_destroy);
|
|
|
|
|
|
|
|
void sk_psock_drop(struct sock *sk, struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
rcu_assign_sk_user_data(sk, NULL);
|
|
|
|
sk_psock_cork_free(psock);
|
2018-12-20 12:35:34 -07:00
|
|
|
sk_psock_zap_ingress(psock);
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
sk_psock_restore_proto(sk, psock);
|
|
|
|
|
|
|
|
write_lock_bh(&sk->sk_callback_lock);
|
|
|
|
if (psock->progs.skb_parser)
|
|
|
|
sk_psock_stop_strp(sk, psock);
|
|
|
|
write_unlock_bh(&sk->sk_callback_lock);
|
|
|
|
sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
|
|
|
|
|
2018-11-07 16:09:25 -07:00
|
|
|
call_rcu(&psock->rcu, sk_psock_destroy);
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_psock_drop);
|
|
|
|
|
|
|
|
static int sk_psock_map_verd(int verdict, bool redir)
|
|
|
|
{
|
|
|
|
switch (verdict) {
|
|
|
|
case SK_PASS:
|
|
|
|
return redir ? __SK_REDIRECT : __SK_PASS;
|
|
|
|
case SK_DROP:
|
|
|
|
default:
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
return __SK_DROP;
|
|
|
|
}
|
|
|
|
|
|
|
|
int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
|
|
|
|
struct sk_msg *msg)
|
|
|
|
{
|
|
|
|
struct bpf_prog *prog;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
preempt_disable();
|
|
|
|
rcu_read_lock();
|
|
|
|
prog = READ_ONCE(psock->progs.msg_parser);
|
|
|
|
if (unlikely(!prog)) {
|
|
|
|
ret = __SK_PASS;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
sk_msg_compute_data_pointers(msg);
|
|
|
|
msg->sk = sk;
|
|
|
|
ret = BPF_PROG_RUN(prog, msg);
|
|
|
|
ret = sk_psock_map_verd(ret, msg->sk_redir);
|
|
|
|
psock->apply_bytes = msg->apply_bytes;
|
|
|
|
if (ret == __SK_REDIRECT) {
|
|
|
|
if (psock->sk_redir)
|
|
|
|
sock_put(psock->sk_redir);
|
|
|
|
psock->sk_redir = msg->sk_redir;
|
|
|
|
if (!psock->sk_redir) {
|
|
|
|
ret = __SK_DROP;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
sock_hold(psock->sk_redir);
|
|
|
|
}
|
|
|
|
out:
|
|
|
|
rcu_read_unlock();
|
|
|
|
preempt_enable();
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sk_psock_msg_verdict);
|
|
|
|
|
|
|
|
static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog,
|
|
|
|
struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
skb->sk = psock->sk;
|
|
|
|
bpf_compute_data_end_sk_skb(skb);
|
|
|
|
preempt_disable();
|
|
|
|
ret = BPF_PROG_RUN(prog, skb);
|
|
|
|
preempt_enable();
|
|
|
|
/* strparser clones the skb before handing it to a upper layer,
|
|
|
|
* meaning skb_orphan has been called. We NULL sk on the way out
|
|
|
|
* to ensure we don't trigger a BUG_ON() in skb/sk operations
|
|
|
|
* later and because we are not charging the memory of this skb
|
|
|
|
* to any socket yet.
|
|
|
|
*/
|
|
|
|
skb->sk = NULL;
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct sk_psock *sk_psock_from_strp(struct strparser *strp)
|
|
|
|
{
|
|
|
|
struct sk_psock_parser *parser;
|
|
|
|
|
|
|
|
parser = container_of(strp, struct sk_psock_parser, strp);
|
|
|
|
return container_of(parser, struct sk_psock, parser);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_verdict_apply(struct sk_psock *psock,
|
|
|
|
struct sk_buff *skb, int verdict)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock_other;
|
|
|
|
struct sock *sk_other;
|
|
|
|
bool ingress;
|
|
|
|
|
|
|
|
switch (verdict) {
|
2018-12-20 12:35:32 -07:00
|
|
|
case __SK_PASS:
|
|
|
|
sk_other = psock->sk;
|
|
|
|
if (sock_flag(sk_other, SOCK_DEAD) ||
|
|
|
|
!sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) {
|
|
|
|
goto out_free;
|
|
|
|
}
|
|
|
|
if (atomic_read(&sk_other->sk_rmem_alloc) <=
|
|
|
|
sk_other->sk_rcvbuf) {
|
|
|
|
struct tcp_skb_cb *tcp = TCP_SKB_CB(skb);
|
|
|
|
|
|
|
|
tcp->bpf.flags |= BPF_F_INGRESS;
|
|
|
|
skb_queue_tail(&psock->ingress_skb, skb);
|
|
|
|
schedule_work(&psock->work);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
goto out_free;
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
case __SK_REDIRECT:
|
|
|
|
sk_other = tcp_skb_bpf_redirect_fetch(skb);
|
|
|
|
if (unlikely(!sk_other))
|
|
|
|
goto out_free;
|
|
|
|
psock_other = sk_psock(sk_other);
|
|
|
|
if (!psock_other || sock_flag(sk_other, SOCK_DEAD) ||
|
|
|
|
!sk_psock_test_state(psock_other, SK_PSOCK_TX_ENABLED))
|
|
|
|
goto out_free;
|
|
|
|
ingress = tcp_skb_bpf_ingress(skb);
|
|
|
|
if ((!ingress && sock_writeable(sk_other)) ||
|
|
|
|
(ingress &&
|
|
|
|
atomic_read(&sk_other->sk_rmem_alloc) <=
|
|
|
|
sk_other->sk_rcvbuf)) {
|
|
|
|
if (!ingress)
|
|
|
|
skb_set_owner_w(skb, sk_other);
|
|
|
|
skb_queue_tail(&psock_other->ingress_skb, skb);
|
|
|
|
schedule_work(&psock_other->work);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
/* fall-through */
|
|
|
|
case __SK_DROP:
|
|
|
|
/* fall-through */
|
|
|
|
default:
|
|
|
|
out_free:
|
|
|
|
kfree_skb(skb);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_strp_read(struct strparser *strp, struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = sk_psock_from_strp(strp);
|
|
|
|
struct bpf_prog *prog;
|
|
|
|
int ret = __SK_DROP;
|
|
|
|
|
|
|
|
rcu_read_lock();
|
|
|
|
prog = READ_ONCE(psock->progs.skb_verdict);
|
|
|
|
if (likely(prog)) {
|
|
|
|
skb_orphan(skb);
|
|
|
|
tcp_skb_bpf_redirect_clear(skb);
|
|
|
|
ret = sk_psock_bpf_run(psock, prog, skb);
|
|
|
|
ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb));
|
|
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
|
|
sk_psock_verdict_apply(psock, skb, ret);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int sk_psock_strp_read_done(struct strparser *strp, int err)
|
|
|
|
{
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int sk_psock_strp_parse(struct strparser *strp, struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock = sk_psock_from_strp(strp);
|
|
|
|
struct bpf_prog *prog;
|
|
|
|
int ret = skb->len;
|
|
|
|
|
|
|
|
rcu_read_lock();
|
|
|
|
prog = READ_ONCE(psock->progs.skb_parser);
|
|
|
|
if (likely(prog))
|
|
|
|
ret = sk_psock_bpf_run(psock, prog, skb);
|
|
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Called with socket lock held. */
|
2018-12-20 12:35:33 -07:00
|
|
|
static void sk_psock_strp_data_ready(struct sock *sk)
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
{
|
|
|
|
struct sk_psock *psock;
|
|
|
|
|
|
|
|
rcu_read_lock();
|
|
|
|
psock = sk_psock(sk);
|
|
|
|
if (likely(psock)) {
|
|
|
|
write_lock_bh(&sk->sk_callback_lock);
|
|
|
|
strp_data_ready(&psock->parser.strp);
|
|
|
|
write_unlock_bh(&sk->sk_callback_lock);
|
|
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
|
|
}
|
|
|
|
|
|
|
|
static void sk_psock_write_space(struct sock *sk)
|
|
|
|
{
|
|
|
|
struct sk_psock *psock;
|
|
|
|
void (*write_space)(struct sock *sk);
|
|
|
|
|
|
|
|
rcu_read_lock();
|
|
|
|
psock = sk_psock(sk);
|
|
|
|
if (likely(psock && sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)))
|
|
|
|
schedule_work(&psock->work);
|
|
|
|
write_space = psock->saved_write_space;
|
|
|
|
rcu_read_unlock();
|
|
|
|
write_space(sk);
|
|
|
|
}
|
|
|
|
|
|
|
|
int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
static const struct strp_callbacks cb = {
|
|
|
|
.rcv_msg = sk_psock_strp_read,
|
|
|
|
.read_sock_done = sk_psock_strp_read_done,
|
|
|
|
.parse_msg = sk_psock_strp_parse,
|
|
|
|
};
|
|
|
|
|
|
|
|
psock->parser.enabled = false;
|
|
|
|
return strp_init(&psock->parser.strp, sk, &cb);
|
|
|
|
}
|
|
|
|
|
|
|
|
void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
struct sk_psock_parser *parser = &psock->parser;
|
|
|
|
|
|
|
|
if (parser->enabled)
|
|
|
|
return;
|
|
|
|
|
|
|
|
parser->saved_data_ready = sk->sk_data_ready;
|
2018-12-20 12:35:33 -07:00
|
|
|
sk->sk_data_ready = sk_psock_strp_data_ready;
|
bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.
This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.
Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.
The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.
Joint work with John.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 18:45:58 -06:00
|
|
|
sk->sk_write_space = sk_psock_write_space;
|
|
|
|
parser->enabled = true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
|
|
|
|
{
|
|
|
|
struct sk_psock_parser *parser = &psock->parser;
|
|
|
|
|
|
|
|
if (!parser->enabled)
|
|
|
|
return;
|
|
|
|
|
|
|
|
sk->sk_data_ready = parser->saved_data_ready;
|
|
|
|
parser->saved_data_ready = NULL;
|
|
|
|
strp_stop(&parser->strp);
|
|
|
|
parser->enabled = false;
|
|
|
|
}
|