Mercurial > hg > nginx-quic
view src/os/win32/ngx_wsasend_chain.c @ 8551:c35b255d80dc quic
HTTP/3: close connection on keepalive_requests * 2.
After receiving GOAWAY, client is not supposed to create new streams. However,
until client reads this frame, we allow it to create new streams, which are
gracefully rejected. To prevent client from abusing this algorithm, a new
limit is introduced. Upon reaching keepalive_requests * 2, server now closes
the entire QUIC connection claiming excessive load.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Thu, 29 Jul 2021 16:01:37 +0300 |
parents | ecf2a9002b37 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_WSABUFS 64 ngx_chain_t * ngx_wsasend_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { int rc; u_char *prev; u_long size, sent, send, prev_send; ngx_err_t err; ngx_event_t *wev; ngx_array_t vec; ngx_chain_t *cl; LPWSABUF wsabuf; WSABUF wsabufs[NGX_WSABUFS]; wev = c->write; if (!wev->ready) { return in; } /* the maximum limit size is the maximum u_long value - the page size */ if (limit == 0 || limit > (off_t) (NGX_MAX_UINT32_VALUE - ngx_pagesize)) { limit = NGX_MAX_UINT32_VALUE - ngx_pagesize; } send = 0; /* * WSABUFs must be 4-byte aligned otherwise * WSASend() will return undocumented WSAEINVAL error. */ vec.elts = wsabufs; vec.size = sizeof(WSABUF); vec.nalloc = ngx_min(NGX_WSABUFS, ngx_max_wsabufs); vec.pool = c->pool; for ( ;; ) { prev = NULL; wsabuf = NULL; prev_send = send; vec.nelts = 0; /* create the WSABUF and coalesce the neighbouring bufs */ for (cl = in; cl && send < limit; cl = cl->next) { if (ngx_buf_special(cl->buf)) { continue; } size = cl->buf->last - cl->buf->pos; if (send + size > limit) { size = (u_long) (limit - send); } if (prev == cl->buf->pos) { wsabuf->len += cl->buf->last - cl->buf->pos; } else { if (vec.nelts == vec.nalloc) { break; } wsabuf = ngx_array_push(&vec); if (wsabuf == NULL) { return NGX_CHAIN_ERROR; } wsabuf->buf = (char *) cl->buf->pos; wsabuf->len = cl->buf->last - cl->buf->pos; } prev = cl->buf->last; send += size; } sent = 0; rc = WSASend(c->fd, vec.elts, vec.nelts, &sent, 0, NULL, NULL); if (rc == -1) { err = ngx_errno; if (err == WSAEWOULDBLOCK) { ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "WSASend() not ready"); } else { wev->error = 1; ngx_connection_error(c, err, "WSASend() failed"); return NGX_CHAIN_ERROR; } } ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "WSASend: fd:%d, s:%ul", c->fd, sent); c->sent += sent; in = ngx_chain_update_sent(in, sent); if (send - prev_send != sent) { wev->ready = 0; return in; } if (send >= limit || in == NULL) { return in; } } } ngx_chain_t * ngx_overlapped_wsasend_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { int rc; u_char *prev; u_long size, send, sent; ngx_err_t err; ngx_event_t *wev; ngx_array_t vec; ngx_chain_t *cl; LPWSAOVERLAPPED ovlp; LPWSABUF wsabuf; WSABUF wsabufs[NGX_WSABUFS]; wev = c->write; if (!wev->ready) { return in; } ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "wev->complete: %d", wev->complete); if (!wev->complete) { /* post the overlapped WSASend() */ /* the maximum limit size is the maximum u_long value - the page size */ if (limit == 0 || limit > (off_t) (NGX_MAX_UINT32_VALUE - ngx_pagesize)) { limit = NGX_MAX_UINT32_VALUE - ngx_pagesize; } /* * WSABUFs must be 4-byte aligned otherwise * WSASend() will return undocumented WSAEINVAL error. */ vec.elts = wsabufs; vec.nelts = 0; vec.size = sizeof(WSABUF); vec.nalloc = ngx_min(NGX_WSABUFS, ngx_max_wsabufs); vec.pool = c->pool; send = 0; prev = NULL; wsabuf = NULL; /* create the WSABUF and coalesce the neighbouring bufs */ for (cl = in; cl && send < limit; cl = cl->next) { if (ngx_buf_special(cl->buf)) { continue; } size = cl->buf->last - cl->buf->pos; if (send + size > limit) { size = (u_long) (limit - send); } if (prev == cl->buf->pos) { wsabuf->len += cl->buf->last - cl->buf->pos; } else { if (vec.nelts == vec.nalloc) { break; } wsabuf = ngx_array_push(&vec); if (wsabuf == NULL) { return NGX_CHAIN_ERROR; } wsabuf->buf = (char *) cl->buf->pos; wsabuf->len = cl->buf->last - cl->buf->pos; } prev = cl->buf->last; send += size; } ovlp = (LPWSAOVERLAPPED) &c->write->ovlp; ngx_memzero(ovlp, sizeof(WSAOVERLAPPED)); rc = WSASend(c->fd, vec.elts, vec.nelts, &sent, 0, ovlp, NULL); wev->complete = 0; if (rc == -1) { err = ngx_errno; if (err == WSA_IO_PENDING) { ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "WSASend() posted"); wev->active = 1; return in; } else { wev->error = 1; ngx_connection_error(c, err, "WSASend() failed"); return NGX_CHAIN_ERROR; } } else if (ngx_event_flags & NGX_USE_IOCP_EVENT) { /* * if a socket was bound with I/O completion port then * GetQueuedCompletionStatus() would anyway return its status * despite that WSASend() was already complete */ wev->active = 1; return in; } ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "WSASend: fd:%d, s:%ul", c->fd, sent); } else { /* the overlapped WSASend() complete */ wev->complete = 0; wev->active = 0; if (ngx_event_flags & NGX_USE_IOCP_EVENT) { if (wev->ovlp.error) { ngx_connection_error(c, wev->ovlp.error, "WSASend() failed"); return NGX_CHAIN_ERROR; } sent = wev->available; } else { if (WSAGetOverlappedResult(c->fd, (LPWSAOVERLAPPED) &wev->ovlp, &sent, 0, NULL) == 0) { ngx_connection_error(c, ngx_socket_errno, "WSASend() or WSAGetOverlappedResult() failed"); return NGX_CHAIN_ERROR; } } } ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "WSASend ovlp: fd:%d, s:%ul", c->fd, sent); c->sent += sent; in = ngx_chain_update_sent(in, sent); if (in) { wev->ready = 0; } else { wev->ready = 1; } return in; }