Mercurial > hg > nginx
view src/event/quic/ngx_event_quic_udp.c @ 9153:8f7e6d8c061e
QUIC: use last client dcid to receive initial packets.
Previously, original dcid was used to receive initial client packets in case
server initial response was lost. However, last dcid should be used instead.
These two are the same unless retry is used. In case of retry, client resends
initial packet with a new dcid, that is different from the original dcid. If
server response is lost, the client resends this packet again with the same
dcid. This is shown in RFC 9000, 7.3. Authenticating Connection IDs, Figure 8.
The issue manifested itself with creating multiple server sessions in response
to each post-retry client initial packet, if server response is lost.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Wed, 30 Aug 2023 11:09:21 +0400 |
parents | 68fa4b86ed46 |
children |
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_event_quic_connection.h> static void ngx_quic_close_accepted_connection(ngx_connection_t *c); static ngx_connection_t *ngx_quic_lookup_connection(ngx_listening_t *ls, ngx_str_t *key, struct sockaddr *local_sockaddr, socklen_t local_socklen); void ngx_quic_recvmsg(ngx_event_t *ev) { ssize_t n; ngx_str_t key; ngx_buf_t buf; ngx_log_t *log; ngx_err_t err; socklen_t socklen, local_socklen; ngx_event_t *rev, *wev; struct iovec iov[1]; struct msghdr msg; ngx_sockaddr_t sa, lsa; struct sockaddr *sockaddr, *local_sockaddr; ngx_listening_t *ls; ngx_event_conf_t *ecf; ngx_connection_t *c, *lc; ngx_quic_socket_t *qsock; static u_char buffer[NGX_QUIC_MAX_UDP_PAYLOAD_SIZE]; #if (NGX_HAVE_ADDRINFO_CMSG) u_char msg_control[CMSG_SPACE(sizeof(ngx_addrinfo_t))]; #endif if (ev->timedout) { if (ngx_enable_accept_events((ngx_cycle_t *) ngx_cycle) != NGX_OK) { return; } ev->timedout = 0; } ecf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_event_core_module); if (!(ngx_event_flags & NGX_USE_KQUEUE_EVENT)) { ev->available = ecf->multi_accept; } lc = ev->data; ls = lc->listening; ev->ready = 0; ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "quic recvmsg on %V, ready: %d", &ls->addr_text, ev->available); do { ngx_memzero(&msg, sizeof(struct msghdr)); iov[0].iov_base = (void *) buffer; iov[0].iov_len = sizeof(buffer); msg.msg_name = &sa; msg.msg_namelen = sizeof(ngx_sockaddr_t); msg.msg_iov = iov; msg.msg_iovlen = 1; #if (NGX_HAVE_ADDRINFO_CMSG) if (ls->wildcard) { msg.msg_control = &msg_control; msg.msg_controllen = sizeof(msg_control); ngx_memzero(&msg_control, sizeof(msg_control)); } #endif n = recvmsg(lc->fd, &msg, 0); if (n == -1) { err = ngx_socket_errno; if (err == NGX_EAGAIN) { ngx_log_debug0(NGX_LOG_DEBUG_EVENT, ev->log, err, "quic recvmsg() not ready"); return; } ngx_log_error(NGX_LOG_ALERT, ev->log, err, "quic recvmsg() failed"); return; } #if (NGX_HAVE_ADDRINFO_CMSG) if (msg.msg_flags & (MSG_TRUNC|MSG_CTRUNC)) { ngx_log_error(NGX_LOG_ALERT, ev->log, 0, "quic recvmsg() truncated data"); continue; } #endif sockaddr = msg.msg_name; socklen = msg.msg_namelen; if (socklen > (socklen_t) sizeof(ngx_sockaddr_t)) { socklen = sizeof(ngx_sockaddr_t); } #if (NGX_HAVE_UNIX_DOMAIN) if (sockaddr->sa_family == AF_UNIX) { struct sockaddr_un *saun = (struct sockaddr_un *) sockaddr; if (socklen <= (socklen_t) offsetof(struct sockaddr_un, sun_path) || saun->sun_path[0] == '\0') { ngx_log_debug0(NGX_LOG_DEBUG_EVENT, ngx_cycle->log, 0, "unbound unix socket"); goto next; } } #endif local_sockaddr = ls->sockaddr; local_socklen = ls->socklen; #if (NGX_HAVE_ADDRINFO_CMSG) if (ls->wildcard) { struct cmsghdr *cmsg; ngx_memcpy(&lsa, local_sockaddr, local_socklen); local_sockaddr = &lsa.sockaddr; for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = CMSG_NXTHDR(&msg, cmsg)) { if (ngx_get_srcaddr_cmsg(cmsg, local_sockaddr) == NGX_OK) { break; } } } #endif if (ngx_quic_get_packet_dcid(ev->log, buffer, n, &key) != NGX_OK) { goto next; } c = ngx_quic_lookup_connection(ls, &key, local_sockaddr, local_socklen); if (c) { #if (NGX_DEBUG) if (c->log->log_level & NGX_LOG_DEBUG_EVENT) { ngx_log_handler_pt handler; handler = c->log->handler; c->log->handler = NULL; ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "quic recvmsg: fd:%d n:%z", c->fd, n); c->log->handler = handler; } #endif ngx_memzero(&buf, sizeof(ngx_buf_t)); buf.pos = buffer; buf.last = buffer + n; buf.start = buf.pos; buf.end = buffer + sizeof(buffer); qsock = ngx_quic_get_socket(c); ngx_memcpy(&qsock->sockaddr, sockaddr, socklen); qsock->socklen = socklen; c->udp->buffer = &buf; rev = c->read; rev->ready = 1; rev->active = 0; rev->handler(rev); if (c->udp) { c->udp->buffer = NULL; } rev->ready = 0; rev->active = 1; goto next; } #if (NGX_STAT_STUB) (void) ngx_atomic_fetch_add(ngx_stat_accepted, 1); #endif ngx_accept_disabled = ngx_cycle->connection_n / 8 - ngx_cycle->free_connection_n; c = ngx_get_connection(lc->fd, ev->log); if (c == NULL) { return; } c->shared = 1; c->type = SOCK_DGRAM; c->socklen = socklen; #if (NGX_STAT_STUB) (void) ngx_atomic_fetch_add(ngx_stat_active, 1); #endif c->pool = ngx_create_pool(ls->pool_size, ev->log); if (c->pool == NULL) { ngx_quic_close_accepted_connection(c); return; } c->sockaddr = ngx_palloc(c->pool, NGX_SOCKADDRLEN); if (c->sockaddr == NULL) { ngx_quic_close_accepted_connection(c); return; } ngx_memcpy(c->sockaddr, sockaddr, socklen); log = ngx_palloc(c->pool, sizeof(ngx_log_t)); if (log == NULL) { ngx_quic_close_accepted_connection(c); return; } *log = ls->log; c->log = log; c->pool->log = log; c->listening = ls; if (local_sockaddr == &lsa.sockaddr) { local_sockaddr = ngx_palloc(c->pool, local_socklen); if (local_sockaddr == NULL) { ngx_quic_close_accepted_connection(c); return; } ngx_memcpy(local_sockaddr, &lsa, local_socklen); } c->local_sockaddr = local_sockaddr; c->local_socklen = local_socklen; c->buffer = ngx_create_temp_buf(c->pool, n); if (c->buffer == NULL) { ngx_quic_close_accepted_connection(c); return; } c->buffer->last = ngx_cpymem(c->buffer->last, buffer, n); rev = c->read; wev = c->write; rev->active = 1; wev->ready = 1; rev->log = log; wev->log = log; /* * TODO: MT: - ngx_atomic_fetch_add() * or protection by critical section or light mutex * * TODO: MP: - allocated in a shared memory * - ngx_atomic_fetch_add() * or protection by critical section or light mutex */ c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1); c->start_time = ngx_current_msec; #if (NGX_STAT_STUB) (void) ngx_atomic_fetch_add(ngx_stat_handled, 1); #endif if (ls->addr_ntop) { c->addr_text.data = ngx_pnalloc(c->pool, ls->addr_text_max_len); if (c->addr_text.data == NULL) { ngx_quic_close_accepted_connection(c); return; } c->addr_text.len = ngx_sock_ntop(c->sockaddr, c->socklen, c->addr_text.data, ls->addr_text_max_len, 0); if (c->addr_text.len == 0) { ngx_quic_close_accepted_connection(c); return; } } #if (NGX_DEBUG) { ngx_str_t addr; u_char text[NGX_SOCKADDR_STRLEN]; ngx_debug_accepted_connection(ecf, c); if (log->log_level & NGX_LOG_DEBUG_EVENT) { addr.data = text; addr.len = ngx_sock_ntop(c->sockaddr, c->socklen, text, NGX_SOCKADDR_STRLEN, 1); ngx_log_debug4(NGX_LOG_DEBUG_EVENT, log, 0, "*%uA quic recvmsg: %V fd:%d n:%z", c->number, &addr, c->fd, n); } } #endif log->data = NULL; log->handler = NULL; ls->handler(c); next: if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) { ev->available -= n; } } while (ev->available); } static void ngx_quic_close_accepted_connection(ngx_connection_t *c) { ngx_free_connection(c); c->fd = (ngx_socket_t) -1; if (c->pool) { ngx_destroy_pool(c->pool); } #if (NGX_STAT_STUB) (void) ngx_atomic_fetch_add(ngx_stat_active, -1); #endif } static ngx_connection_t * ngx_quic_lookup_connection(ngx_listening_t *ls, ngx_str_t *key, struct sockaddr *local_sockaddr, socklen_t local_socklen) { uint32_t hash; ngx_int_t rc; ngx_connection_t *c; ngx_rbtree_node_t *node, *sentinel; ngx_quic_socket_t *qsock; if (key->len == 0) { return NULL; } node = ls->rbtree.root; sentinel = ls->rbtree.sentinel; hash = ngx_crc32_long(key->data, key->len); while (node != sentinel) { if (hash < node->key) { node = node->left; continue; } if (hash > node->key) { node = node->right; continue; } /* hash == node->key */ qsock = (ngx_quic_socket_t *) node; rc = ngx_memn2cmp(key->data, qsock->sid.id, key->len, qsock->sid.len); c = qsock->udp.connection; if (rc == 0 && ls->wildcard) { rc = ngx_cmp_sockaddr(local_sockaddr, local_socklen, c->local_sockaddr, c->local_socklen, 1); } if (rc == 0) { c->udp = &qsock->udp; return c; } node = (rc < 0) ? node->left : node->right; } return NULL; }