1
0
Fork 0
mirror of https://github.com/warmcat/libwebsockets.git synced 2025-03-16 00:00:07 +01:00
libwebsockets/lib/plat/windows/windows-spawn.c

576 lines
14 KiB
C
Raw Permalink Normal View History

/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010 - 2020 Andy Green <andy@warmcat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include "private-lib-core.h"
#include <tchar.h>
#include <stdio.h>
#include <strsafe.h>
void
lws_spawn_timeout(struct lws_sorted_usec_list *sul)
{
struct lws_spawn_piped *lsp = lws_container_of(sul,
struct lws_spawn_piped, sul);
lwsl_warn("%s: spawn exceeded timeout, killing\n", __func__);
lws_spawn_piped_kill_child_process(lsp);
}
2020-05-04 07:24:58 +01:00
void
lws_spawn_sul_reap(struct lws_sorted_usec_list *sul)
{
struct lws_spawn_piped *lsp = lws_container_of(sul,
struct lws_spawn_piped, sul_reap);
lwsl_notice("%s: reaping spawn after last stdpipe, tries left %d\n",
__func__, lsp->reap_retry_budget);
if (!lws_spawn_reap(lsp) && !lsp->pipes_alive) {
if (--lsp->reap_retry_budget) {
lws_sul_schedule(lsp->info.vh->context, lsp->info.tsi,
&lsp->sul_reap, lws_spawn_sul_reap,
250 * LWS_US_PER_MS);
} else {
lwsl_err("%s: Unable to reap lsp %p, killing\n",
__func__, lsp);
lsp->reap_retry_budget = 20;
lws_spawn_piped_kill_child_process(lsp);
}
}
2020-05-04 07:24:58 +01:00
}
static struct lws *
lws_create_basic_wsi(struct lws_context *context, int tsi,
const struct lws_role_ops *ops)
{
2020-11-16 19:32:58 +00:00
struct lws_context_per_thread *pt = &context->pt[tsi];
struct lws *new_wsi;
if (!context->vhost_list)
return NULL;
if ((unsigned int)context->pt[tsi].fds_count ==
context->fd_limit_per_thread - 1) {
lwsl_err("no space for new conn\n");
return NULL;
}
lws_context_lock(context, __func__);
2021-06-26 17:24:19 +01:00
new_wsi = __lws_wsi_create_with_role(context, tsi, ops, NULL);
lws_context_unlock(context);
if (new_wsi == NULL) {
lwsl_err("Out of memory for new connection\n");
return NULL;
}
new_wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
/* initialize the instance struct */
lws_role_transition(new_wsi, 0, LRS_ESTABLISHED, ops);
new_wsi->hdr_parsing_completed = 0;
new_wsi->position_in_fds_table = LWS_NO_FDS_POS;
/*
* these can only be set once the protocol is known
* we set an unestablished connection's protocol pointer
* to the start of the defauly vhost supported list, so it can look
* for matching ones during the handshake
*/
new_wsi->user_space = NULL;
new_wsi->desc.sockfd = LWS_SOCK_INVALID;
return new_wsi;
}
void
lws_spawn_piped_destroy(struct lws_spawn_piped **_lsp)
{
struct lws_spawn_piped *lsp = *_lsp;
struct lws *wsi;
int n;
if (!lsp)
return;
for (n = 0; n < 3; n++) {
if (lsp->pipe_fds[n][!!(n == 0)]) {
CloseHandle(lsp->pipe_fds[n][n == 0]);
lsp->pipe_fds[n][n == 0] = NULL;
}
for (n = 0; n < 3; n++) {
if (lsp->stdwsi[n]) {
lwsl_notice("%s: closing stdwsi %d\n", __func__, n);
wsi = lsp->stdwsi[n];
lsp->stdwsi[n]->desc.filefd = NULL;
lsp->stdwsi[n] = NULL;
lws_set_timeout(wsi, 1, LWS_TO_KILL_SYNC);
}
}
}
lws_dll2_remove(&lsp->dll);
lws_sul_cancel(&lsp->sul);
lws_sul_cancel(&lsp->sul_reap);
lws_sul_cancel(&lsp->sul_poll);
lwsl_warn("%s: deleting lsp\n", __func__);
lws_free_set_NULL((*_lsp));
}
int
lws_spawn_reap(struct lws_spawn_piped *lsp)
{
void *opaque = lsp->info.opaque;
lsp_cb_t cb = lsp->info.reap_cb;
struct _lws_siginfo_t lsi;
lws_usec_t acct[4];
DWORD ex;
if (!lsp->child_pid)
return 0;
if (!GetExitCodeProcess(lsp->child_pid, &ex)) {
lwsl_notice("%s: GetExitCodeProcess failed\n", __func__);
return 0;
}
/* nonzero = success */
if (ex == STILL_ACTIVE) {
lwsl_notice("%s: still active\n", __func__);
return 0;
}
/* mark the earliest time we knew he had gone */
if (!lsp->reaped) {
lsp->reaped = lws_now_usecs();
/*
* Switch the timeout to restrict the amount of grace time
* to drain stdwsi
*/
lws_sul_schedule(lsp->info.vh->context, lsp->info.tsi,
&lsp->sul, lws_spawn_timeout,
5 * LWS_US_PER_SEC);
}
/*
* Stage finalizing our reaction to the process going down until the
* stdwsi flushed whatever is in flight and all noticed they were
* closed. For that reason, each stdwsi close must call lws_spawn_reap
* to check if that was the last one and we can proceed with the reap.
*/
if (!lsp->ungraceful && lsp->pipes_alive) {
lwsl_notice("%s: stdwsi alive, not reaping\n", __func__);
return 0;
}
/* we reached the reap point, no need for timeout wait */
lws_sul_cancel(&lsp->sul);
/*
* All the stdwsi went down, nothing more is coming... it's over
* Collect the final information and then reap the dead process
*/
lsi.retcode = 0x10000 | (int)ex;
lwsl_notice("%s: process exit 0x%x\n", __func__, lsi.retcode);
lsp->child_pid = NULL;
/* destroy the lsp itself first (it's freed and plsp set NULL */
if (lsp->info.plsp)
lws_spawn_piped_destroy(lsp->info.plsp);
/* then do the parent callback informing it's destroyed */
memset(acct, 0, sizeof(acct));
if (cb)
cb(opaque, acct, &lsi, 0);
lwsl_notice("%s: completed reap\n", __func__);
return 1; /* was reaped */
}
int
lws_spawn_piped_kill_child_process(struct lws_spawn_piped *lsp)
{
if (!lsp->child_pid)
return 1;
lsp->ungraceful = 1; /* don't wait for flushing, just kill it */
if (lws_spawn_reap(lsp))
/* that may have invalidated lsp */
return 0;
lwsl_warn("%s: calling TerminateProcess on child pid\n", __func__);
TerminateProcess(lsp->child_pid, 252);
lws_spawn_reap(lsp);
/* that may have invalidated lsp */
return 0;
}
static void
windows_pipe_poll_hack(lws_sorted_usec_list_t *sul)
{
struct lws_spawn_piped *lsp = lws_container_of(sul,
struct lws_spawn_piped, sul_poll);
struct lws *wsi, *wsi1;
DWORD br;
char c;
/*
* Do it first, we know lsp exists and if it's destroyed inbetweentimes,
* it will already have cancelled this
*/
lws_sul_schedule(lsp->context, 0, &lsp->sul_poll,
windows_pipe_poll_hack, 50 * LWS_US_PER_MS);
wsi = lsp->stdwsi[LWS_STDOUT];
wsi1 = lsp->stdwsi[LWS_STDERR];
if (wsi && lsp->pipe_fds[LWS_STDOUT][0] != NULL) {
if (!PeekNamedPipe(lsp->pipe_fds[LWS_STDOUT][0], &c, 1, &br,
NULL, NULL)) {
lwsl_notice("%s: stdout pipe errored\n", __func__);
CloseHandle(lsp->stdwsi[LWS_STDOUT]->desc.filefd);
lsp->pipe_fds[LWS_STDOUT][0] = NULL;
lsp->stdwsi[LWS_STDOUT]->desc.filefd = NULL;
lsp->stdwsi[LWS_STDOUT] = NULL;
lws_set_timeout(wsi, 1, LWS_TO_KILL_SYNC);
if (lsp->stdwsi[LWS_STDIN]) {
lwsl_notice("%s: closing stdin from stdout close\n",
__func__);
CloseHandle(lsp->stdwsi[LWS_STDIN]->desc.filefd);
wsi = lsp->stdwsi[LWS_STDIN];
lsp->stdwsi[LWS_STDIN]->desc.filefd = NULL;
lsp->stdwsi[LWS_STDIN] = NULL;
lsp->pipe_fds[LWS_STDIN][1] = NULL;
lws_set_timeout(wsi, 1, LWS_TO_KILL_SYNC);
}
/*
* lsp may be destroyed by here... if we wanted to
* handle a still-extant stderr we'll get it next time
*/
return;
} else
if (br)
fakewsi: replace with smaller substructure Currently we always reserve a fakewsi per pt so events that don't have a related actual wsi, like vhost-protocol-init or vhost cert init via protocol callback can make callbacks that look reasonable to user protocol handler code expecting a valid wsi every time. This patch splits out stuff that user callbacks often unconditionally expect to be in a wsi, like context pointer, vhost pointer etc into a substructure, which is composed into struct lws at the top of it. Internal references (struct lws is opaque, so there are only internal references) are all updated to go via the substructre, the compiler should make that a NOP. Helpers are added when fakewsi is used and referenced. If not PLAT_FREERTOS, we continue to provide a full fakewsi in the pt as before, although the helpers improve consistency by zeroing down the substructure. There is a huge amount of user code out there over the last 10 years that did not always have the minimal examples to follow, some of it does some unexpected things. If it is PLAT_FREERTOS, that is a newer thing in lws and users have the benefit of being able to follow the minimal examples' approach. For PLAT_FREERTOS we don't reserve the fakewsi in the pt any more, saving around 800 bytes. The helpers then create a struct lws_a (the substructure) on the stack, zero it down (but it is only like 4 pointers) and prepare it with whatever we know like the context. Then we cast it to a struct lws * and use it in the user protocol handler call. In this case, the remainder of the struct lws is undefined. However the amount of old protocol handlers that might touch things outside of the substructure in PLAT_FREERTOS is very limited compared to legacy lws user code and the saving is significant on constrained devices. User handlers should not be touching everything in a wsi every time anyway, there are several cases where there is no valid wsi to do the call with. Dereference of things outside the substructure should only happen when the callback reason shows there is a valid wsi bound to the activity (as in all the minimal examples).
2020-07-19 08:33:46 +01:00
wsi->a.protocol->callback(wsi,
LWS_CALLBACK_RAW_RX_FILE,
NULL, NULL, 0);
}
/*
* lsp may have been destroyed above
*/
if (wsi1 && lsp->pipe_fds[LWS_STDERR][0]) {
if (!PeekNamedPipe(lsp->pipe_fds[LWS_STDERR][0], &c, 1, &br,
NULL, NULL)) {
lwsl_notice("%s: stderr pipe errored\n", __func__);
CloseHandle(wsi1->desc.filefd);
/*
* Assume is stderr still extant on entry, lsp can't
* have been destroyed by stdout/stdin processing
*/
lsp->stdwsi[LWS_STDERR]->desc.filefd = NULL;
lsp->stdwsi[LWS_STDERR] = NULL;
lsp->pipe_fds[LWS_STDERR][0] = NULL;
lws_set_timeout(wsi1, 1, LWS_TO_KILL_SYNC);
/*
* lsp may have been destroyed above
*/
} else
if (br)
wsi1->a.protocol->callback(wsi1,
LWS_CALLBACK_RAW_RX_FILE,
NULL, NULL, 0);
}
}
/*
* Deals with spawning a subprocess and executing it securely with stdin/out/err
* diverted into pipes
*/
struct lws_spawn_piped *
lws_spawn_piped(const struct lws_spawn_piped_info *i)
{
const struct lws_protocols *pcol = i->vh->context->vhost_list->protocols;
struct lws_context *context = i->vh->context;
struct lws_spawn_piped *lsp;
PROCESS_INFORMATION pi;
SECURITY_ATTRIBUTES sa;
char cli[300], *p;
STARTUPINFO si;
int n;
if (i->protocol_name)
pcol = lws_vhost_name_to_protocol(i->vh, i->protocol_name);
if (!pcol) {
lwsl_err("%s: unknown protocol %s\n", __func__,
i->protocol_name ? i->protocol_name : "default");
return NULL;
}
lsp = lws_zalloc(sizeof(*lsp), __func__);
if (!lsp) {
lwsl_err("%s: OOM\n", __func__);
return NULL;
}
/* wholesale take a copy of info */
lsp->info = *i;
lsp->context = context;
lsp->reap_retry_budget = 20;
/*
* Prepare the stdin / out / err pipes
*/
for (n = 0; n < 3; n++) {
lsp->pipe_fds[n][0] = NULL;
lsp->pipe_fds[n][1] = NULL;
}
/* create pipes for [stdin|stdout] and [stderr] */
memset(&sa, 0, sizeof(sa));
sa.nLength = sizeof(SECURITY_ATTRIBUTES);
sa.bInheritHandle = TRUE; /* inherit the pipes */
sa.lpSecurityDescriptor = NULL;
for (n = 0; n < 3; n++) {
DWORD waitmode = PIPE_NOWAIT;
if (!CreatePipe(&lsp->pipe_fds[n][0], &lsp->pipe_fds[n][1],
&sa, 0)) {
lwsl_err("%s: CreatePipe() failed\n", __func__);
goto bail1;
}
SetNamedPipeHandleState(lsp->pipe_fds[1][0], &waitmode, NULL, NULL);
SetNamedPipeHandleState(lsp->pipe_fds[2][0], &waitmode, NULL, NULL);
/* don't inherit the pipe side that belongs to the parent */
if (!SetHandleInformation(&lsp->pipe_fds[n][!n],
HANDLE_FLAG_INHERIT, 0)) {
lwsl_err("%s: SetHandleInformation() failed\n", __func__);
//goto bail1;
}
}
/* create wsis for each stdin/out/err fd */
for (n = 0; n < 3; n++) {
lsp->stdwsi[n] = lws_create_basic_wsi(i->vh->context, i->tsi,
i->ops ? i->ops : &role_ops_raw_file);
if (!lsp->stdwsi[n]) {
lwsl_err("%s: unable to create lsp stdwsi\n", __func__);
goto bail2;
}
2021-06-26 17:24:19 +01:00
__lws_lc_tag(i->vh->context, &i->vh->context->lcg[LWSLCG_WSI],
&lsp->stdwsi[n]->lc, "nspawn-stdwsi-%d", n);
lsp->stdwsi[n]->lsp_channel = n;
lws_vhost_bind_wsi(i->vh, lsp->stdwsi[n]);
lsp->stdwsi[n]->a.protocol = pcol;
lsp->stdwsi[n]->a.opaque_user_data = i->opaque;
lsp->stdwsi[n]->desc.filefd = lsp->pipe_fds[n][!n];
lsp->stdwsi[n]->file_desc = 1;
lwsl_debug("%s: lsp stdwsi %p: pipe idx %d -> fd %d / %d\n",
__func__, lsp->stdwsi[n], n,
lsp->pipe_fds[n][!!(n == 0)],
lsp->pipe_fds[n][!(n == 0)]);
#if 0
/* read side is 0, stdin we want the write side, others read */
lsp->stdwsi[n]->desc.filefd = lsp->pipe_fds[n][!!(n == 0)];
if (fcntl(lsp->pipe_fds[n][!!(n == 0)], F_SETFL, O_NONBLOCK) < 0) {
lwsl_err("%s: setting NONBLOCK failed\n", __func__);
goto bail2;
}
#endif
}
for (n = 0; n < 3; n++)
if (i->opt_parent) {
lsp->stdwsi[n]->parent = i->opt_parent;
lsp->stdwsi[n]->sibling_list = i->opt_parent->child_list;
i->opt_parent->child_list = lsp->stdwsi[n];
}
lwsl_notice("%s: pipe handles in %p, out %p, err %p\n", __func__,
lsp->stdwsi[LWS_STDIN]->desc.sockfd,
lsp->stdwsi[LWS_STDOUT]->desc.sockfd,
lsp->stdwsi[LWS_STDERR]->desc.sockfd);
/*
* Windows nonblocking pipe handling is a mess that is unable
* to interoperate with WSA-based wait as far as I can tell.
*
* Let's set up a sul to poll the pipes and synthesize the
* protocol callbacks if anything coming.
*/
lws_sul_schedule(context, 0, &lsp->sul_poll, windows_pipe_poll_hack,
50 * LWS_US_PER_MS);
/*
* Windows wants a single string commandline
*/
p = cli;
n = 0;
while (i->exec_array[n]) {
lws_strncpy(p, i->exec_array[n],
sizeof(cli) - lws_ptr_diff(p, cli));
if (sizeof(cli) - lws_ptr_diff(p, cli) < 4)
break;
p += strlen(p);
*p++ = ' ';
*p = '\0';
n++;
}
puts(cli);
memset(&pi, 0, sizeof(pi));
memset(&si, 0, sizeof(si));
si.cb = sizeof(STARTUPINFO);
si.hStdInput = lsp->pipe_fds[LWS_STDIN][0];
si.hStdOutput = lsp->pipe_fds[LWS_STDOUT][1];
si.hStdError = lsp->pipe_fds[LWS_STDERR][1];
si.dwFlags = STARTF_USESTDHANDLES | CREATE_NO_WINDOW;
si.wShowWindow = TRUE;
if (!CreateProcess(NULL, cli, NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi)) {
lwsl_err("%s: CreateProcess failed 0x%x\n", __func__,
(unsigned long)GetLastError());
goto bail3;
}
lsp->child_pid = pi.hProcess;
lwsl_notice("%s: lsp %p spawned PID %d\n", __func__, lsp, lsp->child_pid);
lws_sul_schedule(context, i->tsi, &lsp->sul, lws_spawn_timeout,
i->timeout_us ? i->timeout_us : 300 * LWS_US_PER_SEC);
/*
* close: stdin:r, stdout:w, stderr:w
*/
for (n = 0; n < 3; n++)
CloseHandle(lsp->pipe_fds[n][n != 0]);
lsp->pipes_alive = 3;
lsp->created = lws_now_usecs();
if (i->owner)
lws_dll2_add_head(&lsp->dll, i->owner);
if (i->timeout_us)
lws_sul_schedule(context, i->tsi, &lsp->sul,
lws_spawn_timeout, i->timeout_us);
return lsp;
bail3:
lws_sul_cancel(&lsp->sul_poll);
while (--n >= 0)
__remove_wsi_socket_from_fds(lsp->stdwsi[n]);
bail2:
for (n = 0; n < 3; n++)
if (lsp->stdwsi[n])
__lws_free_wsi(lsp->stdwsi[n]);
bail1:
for (n = 0; n < 3; n++) {
if (lsp->pipe_fds[n][0] >= 0)
CloseHandle(lsp->pipe_fds[n][0]);
if (lsp->pipe_fds[n][1] >= 0)
CloseHandle(lsp->pipe_fds[n][1]);
}
lws_free(lsp);
lwsl_err("%s: failed\n", __func__);
return NULL;
}
void
2020-05-04 07:24:58 +01:00
lws_spawn_stdwsi_closed(struct lws_spawn_piped *lsp, struct lws *wsi)
{
2020-05-04 07:24:58 +01:00
int n;
assert(lsp);
lsp->pipes_alive--;
lwsl_debug("%s: pipes alive %d\n", __func__, lsp->pipes_alive);
2020-05-04 07:24:58 +01:00
if (!lsp->pipes_alive)
lws_sul_schedule(lsp->info.vh->context, lsp->info.tsi,
&lsp->sul_reap, lws_spawn_sul_reap, 1);
for (n = 0; n < 3; n++)
if (lsp->stdwsi[n] == wsi)
lsp->stdwsi[n] = NULL;
}
int
lws_spawn_get_stdfd(struct lws *wsi)
{
return wsi->lsp_channel;
}