nfqws: fix nfq recv result and error handling

This commit is contained in:
bol-van 2024-12-07 20:51:29 +03:00
parent 4e5caf4087
commit c802069a11

View File

@ -152,50 +152,62 @@ static int nfq_cb(struct nfq_q_handle *qh, struct nfgenmsg *nfmsg, struct nfq_da
DLOG("packet: id=%d pass unmodified\n", id);
return nfq_set_verdict2(qh, id, NF_ACCEPT, mark, 0, NULL);
}
static int nfq_main(void)
bool nfq_deinit(struct nfq_handle **h,struct nfq_q_handle **qh)
{
struct nfq_handle *h = NULL;
struct nfq_q_handle *qh = NULL;
int fd,rv;
uint8_t buf[16384] __attribute__((aligned));
if (*qh)
{
DLOG_CONDUP("unbinding from queue %u\n", params.qnum);
nfq_destroy_queue(*qh);
*qh = NULL;
}
if (*h)
{
DLOG_CONDUP("closing library handle\n");
nfq_close(*h);
*h = NULL;
}
}
bool nfq_init(struct nfq_handle **h,struct nfq_q_handle **qh)
{
nfq_deinit(h,qh);
DLOG_CONDUP("opening library handle\n");
h = nfq_open();
if (!h) {
*h = nfq_open();
if (!*h) {
DLOG_PERROR("nfq_open()");
goto exiterr;
}
DLOG_CONDUP("unbinding existing nf_queue handler for AF_INET (if any)\n");
if (nfq_unbind_pf(h, AF_INET) < 0) {
if (nfq_unbind_pf(*h, AF_INET) < 0) {
DLOG_PERROR("nfq_unbind_pf()");
goto exiterr;
}
DLOG_CONDUP("binding nfnetlink_queue as nf_queue handler for AF_INET\n");
if (nfq_bind_pf(h, AF_INET) < 0) {
if (nfq_bind_pf(*h, AF_INET) < 0) {
DLOG_PERROR("nfq_bind_pf()");
goto exiterr;
}
DLOG_CONDUP("binding this socket to queue '%u'\n", params.qnum);
qh = nfq_create_queue(h, params.qnum, &nfq_cb, &params);
*qh = nfq_create_queue(*h, params.qnum, &nfq_cb, &params);
if (!qh) {
DLOG_PERROR("nfq_create_queue()");
goto exiterr;
}
DLOG_CONDUP("setting copy_packet mode\n");
if (nfq_set_mode(qh, NFQNL_COPY_PACKET, 0xffff) < 0) {
if (nfq_set_mode(*qh, NFQNL_COPY_PACKET, 0xffff) < 0) {
DLOG_PERROR("can't set packet_copy mode");
goto exiterr;
}
if (nfq_set_queue_maxlen(qh, Q_MAXLEN) < 0) {
if (nfq_set_queue_maxlen(*qh, Q_MAXLEN) < 0) {
DLOG_PERROR("can't set queue maxlen");
goto exiterr;
}
// accept packets if they cant be handled
if (nfq_set_queue_flags(qh, NFQA_CFG_F_FAIL_OPEN , NFQA_CFG_F_FAIL_OPEN))
if (nfq_set_queue_flags(*qh, NFQA_CFG_F_FAIL_OPEN , NFQA_CFG_F_FAIL_OPEN))
{
DLOG_ERR("can't set queue flags. its OK on linux <3.6\n");
// dot not fail. not supported on old linuxes <3.6
@ -205,6 +217,25 @@ static int nfq_main(void)
if (!rawsend_preinit(params.bind_fix4,params.bind_fix6))
goto exiterr;
// increase socket buffer size. on slow systems reloading hostlist can take a while.
// if too many unhandled packets are received its possible to get "no buffer space available" error
if (!set_socket_buffers(nfq_fd(*h),Q_RCVBUF/2,Q_SNDBUF/2))
goto exiterr;
return true;
exiterr:
nfq_deinit(h,qh);
return false;
}
static int nfq_main(void)
{
uint8_t buf[16384] __attribute__((aligned));
struct nfq_handle *h = NULL;
struct nfq_q_handle *qh = NULL;
int fd,e;
ssize_t rd;
#ifndef __CYGWIN__
sec_harden();
@ -216,36 +247,30 @@ static int nfq_main(void)
pre_desync();
fd = nfq_fd(h);
nfq_init(&h,&qh);
// increase socket buffer size. on slow systems reloading hostlist can take a while.
// if too many unhandled packets are received its possible to get "no buffer space available" error
if (!set_socket_buffers(fd,Q_RCVBUF/2,Q_SNDBUF/2))
goto exiterr;
fd = nfq_fd(h);
do
{
while ((rv = recv(fd, buf, sizeof(buf), 0)) > 0)
while ((rd = recv(fd, buf, sizeof(buf), 0)) >= 0)
{
int r = nfq_handle_packet(h, (char *)buf, rv);
if (rd)
{
int r = nfq_handle_packet(h, (char *)buf, (int)rd);
if (r) DLOG_ERR("nfq_handle_packet error %d\n", r);
}
DLOG_ERR("recv: errno %d\n",errno);
else
DLOG("recv from nfq returned 0 !\n");
}
e=errno;
DLOG_ERR("recv: recv=%zd errno %d\n",rd,e);
errno=e;
DLOG_PERROR("recv");
// do not fail on ENOBUFS
} while(errno==ENOBUFS);
DLOG_CONDUP("unbinding from queue %u\n", params.qnum);
nfq_destroy_queue(qh);
nfq_deinit(&h,&qh);
#ifdef INSANE
/* normally, applications SHOULD NOT issue this command, since
* it detaches other programs/sockets from AF_INET, too ! */
DLOG_CONDUP("unbinding from AF_INET\n");
nfq_unbind_pf(h, AF_INET);
#endif
DLOG_CONDUP("closing library handle\n");
nfq_close(h);
return 0;
exiterr: