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synced 2024-08-21 16:29:59 +00:00
![Daniel Borkmann](/assets/img/avatar_default.png)
Convert kTLS over to make use of sk_msg interface for plaintext and encrypted scattergather data, so it reuses all the sk_msg helpers and data structure which later on in a second step enables to glue this to BPF. This also allows to remove quite a bit of open coded helpers which are covered by the sk_msg API. Recent changes in kTLs80ece6a03a
("tls: Remove redundant vars from tls record structure") and4e6d47206c
("tls: Add support for inplace records encryption") changed the data path handling a bit; while we've kept the latter optimization intact, we had to undo the former change to better fit the sk_msg model, hence the sg_aead_in and sg_aead_out have been brought back and are linked into the sk_msg sgs. Now the kTLS record contains a msg_plaintext and msg_encrypted sk_msg each. In the original code, the zerocopy_from_iter() has been used out of TX but also RX path. For the strparser skb-based RX path, we've left the zerocopy_from_iter() in decrypt_internal() mostly untouched, meaning it has been moved into tls_setup_from_iter() with charging logic removed (as not used from RX). Given RX path is not based on sk_msg objects, we haven't pursued setting up a dummy sk_msg to call into sk_msg_zerocopy_from_iter(), but it could be an option to prusue in a later step. 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>
802 lines
18 KiB
C
802 lines
18 KiB
C
// 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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#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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{
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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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if (msg->sg.end < msg->sg.start &&
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(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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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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{
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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;
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while (len > 0) {
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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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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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if (sk_msg_full(msg)) {
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ret = -ENOSPC;
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break;
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}
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sge = &msg->sg.data[msg->sg.end];
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sg_unmark_end(sge);
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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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}
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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;
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}
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EXPORT_SYMBOL_GPL(sk_msg_alloc);
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int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
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u32 off, u32 len)
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{
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int i = src->sg.start;
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struct scatterlist *sge = sk_msg_elem(src, i);
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u32 sge_len, sge_off;
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if (sk_msg_full(dst))
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return -ENOSPC;
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while (off) {
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if (sge->length > off)
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break;
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off -= sge->length;
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sk_msg_iter_var_next(i);
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if (i == src->sg.end && off)
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return -ENOSPC;
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sge = sk_msg_elem(src, i);
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}
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while (len) {
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sge_len = sge->length - off;
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sge_off = sge->offset + off;
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if (sge_len > len)
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sge_len = len;
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off = 0;
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len -= sge_len;
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sk_msg_page_add(dst, sg_page(sge), sge_len, sge_off);
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sk_mem_charge(sk, sge_len);
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sk_msg_iter_var_next(i);
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if (i == src->sg.end && len)
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return -ENOSPC;
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sge = sk_msg_elem(src, i);
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(sk_msg_clone);
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void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes)
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{
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int i = msg->sg.start;
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do {
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struct scatterlist *sge = sk_msg_elem(msg, i);
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if (bytes < sge->length) {
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sge->length -= bytes;
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sge->offset += bytes;
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sk_mem_uncharge(sk, bytes);
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break;
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}
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sk_mem_uncharge(sk, sge->length);
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bytes -= sge->length;
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sge->length = 0;
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sge->offset = 0;
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sk_msg_iter_var_next(i);
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} while (bytes && i != msg->sg.end);
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msg->sg.start = i;
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}
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EXPORT_SYMBOL_GPL(sk_msg_return_zero);
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void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes)
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{
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int i = msg->sg.start;
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do {
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struct scatterlist *sge = &msg->sg.data[i];
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int uncharge = (bytes < sge->length) ? bytes : sge->length;
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sk_mem_uncharge(sk, uncharge);
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bytes -= uncharge;
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sk_msg_iter_var_next(i);
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} while (i != msg->sg.end);
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}
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EXPORT_SYMBOL_GPL(sk_msg_return);
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static int sk_msg_free_elem(struct sock *sk, struct sk_msg *msg, u32 i,
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bool charge)
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{
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struct scatterlist *sge = sk_msg_elem(msg, i);
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u32 len = sge->length;
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if (charge)
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sk_mem_uncharge(sk, len);
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if (!msg->skb)
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put_page(sg_page(sge));
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memset(sge, 0, sizeof(*sge));
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return len;
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}
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static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i,
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bool charge)
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{
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struct scatterlist *sge = sk_msg_elem(msg, i);
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int freed = 0;
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while (msg->sg.size) {
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msg->sg.size -= sge->length;
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freed += sk_msg_free_elem(sk, msg, i, charge);
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sk_msg_iter_var_next(i);
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sk_msg_check_to_free(msg, i, msg->sg.size);
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sge = sk_msg_elem(msg, i);
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}
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if (msg->skb)
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consume_skb(msg->skb);
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sk_msg_init(msg);
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return freed;
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}
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int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg)
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{
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return __sk_msg_free(sk, msg, msg->sg.start, false);
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}
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EXPORT_SYMBOL_GPL(sk_msg_free_nocharge);
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int sk_msg_free(struct sock *sk, struct sk_msg *msg)
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{
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return __sk_msg_free(sk, msg, msg->sg.start, true);
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}
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EXPORT_SYMBOL_GPL(sk_msg_free);
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static void __sk_msg_free_partial(struct sock *sk, struct sk_msg *msg,
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u32 bytes, bool charge)
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{
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struct scatterlist *sge;
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u32 i = msg->sg.start;
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while (bytes) {
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sge = sk_msg_elem(msg, i);
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if (!sge->length)
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break;
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if (bytes < sge->length) {
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if (charge)
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sk_mem_uncharge(sk, bytes);
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sge->length -= bytes;
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sge->offset += bytes;
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msg->sg.size -= bytes;
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break;
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}
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msg->sg.size -= sge->length;
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bytes -= sge->length;
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sk_msg_free_elem(sk, msg, i, charge);
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sk_msg_iter_var_next(i);
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sk_msg_check_to_free(msg, i, bytes);
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}
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msg->sg.start = i;
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}
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void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes)
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{
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__sk_msg_free_partial(sk, msg, bytes, true);
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}
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EXPORT_SYMBOL_GPL(sk_msg_free_partial);
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void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
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u32 bytes)
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{
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__sk_msg_free_partial(sk, msg, bytes, false);
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}
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void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len)
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{
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int trim = msg->sg.size - len;
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u32 i = msg->sg.end;
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if (trim <= 0) {
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WARN_ON(trim < 0);
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return;
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}
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sk_msg_iter_var_prev(i);
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msg->sg.size = len;
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while (msg->sg.data[i].length &&
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trim >= msg->sg.data[i].length) {
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trim -= msg->sg.data[i].length;
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sk_msg_free_elem(sk, msg, i, true);
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sk_msg_iter_var_prev(i);
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if (!trim)
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goto out;
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}
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msg->sg.data[i].length -= trim;
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sk_mem_uncharge(sk, trim);
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out:
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/* If we trim data before curr pointer update copybreak and current
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* so that any future copy operations start at new copy location.
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* However trimed data that has not yet been used in a copy op
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* does not require an update.
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*/
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if (msg->sg.curr >= i) {
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msg->sg.curr = i;
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msg->sg.copybreak = msg->sg.data[i].length;
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}
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sk_msg_iter_var_next(i);
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msg->sg.end = i;
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}
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EXPORT_SYMBOL_GPL(sk_msg_trim);
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int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
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struct sk_msg *msg, u32 bytes)
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{
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int i, maxpages, ret = 0, num_elems = sk_msg_elem_used(msg);
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const int to_max_pages = MAX_MSG_FRAGS;
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struct page *pages[MAX_MSG_FRAGS];
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ssize_t orig, copied, use, offset;
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orig = msg->sg.size;
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while (bytes > 0) {
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i = 0;
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maxpages = to_max_pages - num_elems;
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if (maxpages == 0) {
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ret = -EFAULT;
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goto out;
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}
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copied = iov_iter_get_pages(from, pages, bytes, maxpages,
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&offset);
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if (copied <= 0) {
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ret = -EFAULT;
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goto out;
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}
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iov_iter_advance(from, copied);
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bytes -= copied;
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msg->sg.size += copied;
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while (copied) {
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use = min_t(int, copied, PAGE_SIZE - offset);
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sg_set_page(&msg->sg.data[msg->sg.end],
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pages[i], use, offset);
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sg_unmark_end(&msg->sg.data[msg->sg.end]);
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sk_mem_charge(sk, use);
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offset = 0;
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copied -= use;
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sk_msg_iter_next(msg, end);
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num_elems++;
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i++;
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}
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/* When zerocopy is mixed with sk_msg_*copy* operations we
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* may have a copybreak set in this case clear and prefer
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* zerocopy remainder when possible.
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*/
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msg->sg.copybreak = 0;
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msg->sg.curr = msg->sg.end;
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}
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out:
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/* Revert iov_iter updates, msg will need to use 'trim' later if it
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* also needs to be cleared.
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*/
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if (ret)
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iov_iter_revert(from, msg->sg.size - orig);
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return ret;
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}
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EXPORT_SYMBOL_GPL(sk_msg_zerocopy_from_iter);
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int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
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struct sk_msg *msg, u32 bytes)
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{
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int ret = -ENOSPC, i = msg->sg.curr;
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struct scatterlist *sge;
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u32 copy, buf_size;
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void *to;
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do {
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sge = sk_msg_elem(msg, i);
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/* This is possible if a trim operation shrunk the buffer */
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if (msg->sg.copybreak >= sge->length) {
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msg->sg.copybreak = 0;
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sk_msg_iter_var_next(i);
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if (i == msg->sg.end)
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break;
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sge = sk_msg_elem(msg, i);
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}
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buf_size = sge->length - msg->sg.copybreak;
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copy = (buf_size > bytes) ? bytes : buf_size;
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to = sg_virt(sge) + msg->sg.copybreak;
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msg->sg.copybreak += copy;
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if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY)
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ret = copy_from_iter_nocache(to, copy, from);
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else
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ret = copy_from_iter(to, copy, from);
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if (ret != copy) {
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ret = -EFAULT;
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goto out;
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}
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bytes -= copy;
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if (!bytes)
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break;
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msg->sg.copybreak = 0;
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sk_msg_iter_var_next(i);
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} while (i != msg->sg.end);
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out:
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msg->sg.curr = i;
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return ret;
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}
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EXPORT_SYMBOL_GPL(sk_msg_memcopy_from_iter);
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static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
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{
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struct sock *sk = psock->sk;
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int copied = 0, num_sge;
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struct sk_msg *msg;
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msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC);
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if (unlikely(!msg))
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return -EAGAIN;
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if (!sk_rmem_schedule(sk, skb, skb->len)) {
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kfree(msg);
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return -EAGAIN;
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}
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sk_msg_init(msg);
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num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
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if (unlikely(num_sge < 0)) {
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kfree(msg);
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return num_sge;
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}
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sk_mem_charge(sk, skb->len);
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copied = skb->len;
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msg->sg.start = 0;
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msg->sg.end = num_sge == MAX_MSG_FRAGS ? 0 : num_sge;
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msg->skb = skb;
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sk_psock_queue_msg(psock, msg);
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sk->sk_data_ready(sk);
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return copied;
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}
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static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
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u32 off, u32 len, bool ingress)
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{
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if (ingress)
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return sk_psock_skb_ingress(psock, skb);
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else
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return skb_send_sock_locked(psock->sk, skb, off, len);
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}
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static void sk_psock_backlog(struct work_struct *work)
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{
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struct sk_psock *psock = container_of(work, struct sk_psock, work);
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struct sk_psock_work_state *state = &psock->work_state;
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struct sk_buff *skb;
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bool ingress;
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u32 len, off;
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int ret;
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/* Lock sock to avoid losing sk_socket during loop. */
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lock_sock(psock->sk);
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if (state->skb) {
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skb = state->skb;
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len = state->len;
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off = state->off;
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state->skb = NULL;
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goto start;
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}
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while ((skb = skb_dequeue(&psock->ingress_skb))) {
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len = skb->len;
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off = 0;
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start:
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ingress = tcp_skb_bpf_ingress(skb);
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do {
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ret = -EIO;
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if (likely(psock->sk->sk_socket))
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ret = sk_psock_handle_skb(psock, skb, off,
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len, ingress);
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if (ret <= 0) {
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if (ret == -EAGAIN) {
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state->skb = skb;
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state->len = len;
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state->off = off;
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goto end;
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}
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/* Hard errors break pipe and stop xmit. */
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sk_psock_report_error(psock, ret ? -ret : EPIPE);
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sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
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kfree_skb(skb);
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goto end;
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}
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off += ret;
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len -= ret;
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} while (len);
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if (!ingress)
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kfree_skb(skb);
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}
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end:
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release_sock(psock->sk);
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}
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struct sk_psock *sk_psock_init(struct sock *sk, int node)
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{
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struct sk_psock *psock = kzalloc_node(sizeof(*psock),
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GFP_ATOMIC | __GFP_NOWARN,
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node);
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if (!psock)
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return NULL;
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psock->sk = sk;
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psock->eval = __SK_NONE;
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INIT_LIST_HEAD(&psock->link);
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spin_lock_init(&psock->link_lock);
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INIT_WORK(&psock->work, sk_psock_backlog);
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INIT_LIST_HEAD(&psock->ingress_msg);
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skb_queue_head_init(&psock->ingress_skb);
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|
|
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. */
|
|
if (psock->parser.enabled)
|
|
strp_done(&psock->parser.strp);
|
|
|
|
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);
|
|
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);
|
|
|
|
call_rcu_sched(&psock->rcu, sk_psock_destroy);
|
|
}
|
|
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) {
|
|
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. */
|
|
static void sk_psock_data_ready(struct sock *sk)
|
|
{
|
|
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;
|
|
sk->sk_data_ready = sk_psock_data_ready;
|
|
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;
|
|
}
|