Mercurial > hg > nginx-quic
view src/event/ngx_event_udp.c @ 8472:aa5f8825f24d
Resolver: fixed label types handling in ngx_resolver_copy().
Previously, anything with any of the two high bits set were interpreted
as compression pointers. This is incorrect, as RFC 1035 clearly states
that "The 10 and 01 combinations are reserved for future use". Further,
the 01 combination is actually allocated for EDNS extended label type
(see RFC 2671 and RFC 6891), not really used though.
Fix is to reject unrecognized label types rather than misinterpreting
them as compression pointers.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 25 May 2021 15:17:41 +0300 |
parents | fdc3d40979b0 |
children | 7f95010f10b7 0f6cc8f73744 |
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #if !(NGX_WIN32) struct ngx_udp_connection_s { ngx_rbtree_node_t node; ngx_connection_t *connection; ngx_buf_t *buffer; }; static void ngx_close_accepted_udp_connection(ngx_connection_t *c); static ssize_t ngx_udp_shared_recv(ngx_connection_t *c, u_char *buf, size_t size); static ngx_int_t ngx_insert_udp_connection(ngx_connection_t *c); static ngx_connection_t *ngx_lookup_udp_connection(ngx_listening_t *ls, struct sockaddr *sockaddr, socklen_t socklen, struct sockaddr *local_sockaddr, socklen_t local_socklen); void ngx_event_recvmsg(ngx_event_t *ev) { ssize_t n; 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; static u_char buffer[65535]; #if (NGX_HAVE_MSGHDR_MSG_CONTROL) #if (NGX_HAVE_IP_RECVDSTADDR) u_char msg_control[CMSG_SPACE(sizeof(struct in_addr))]; #elif (NGX_HAVE_IP_PKTINFO) u_char msg_control[CMSG_SPACE(sizeof(struct in_pktinfo))]; #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) u_char msg_control6[CMSG_SPACE(sizeof(struct in6_pktinfo))]; #endif #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, "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_MSGHDR_MSG_CONTROL) if (ls->wildcard) { #if (NGX_HAVE_IP_RECVDSTADDR || NGX_HAVE_IP_PKTINFO) if (ls->sockaddr->sa_family == AF_INET) { msg.msg_control = &msg_control; msg.msg_controllen = sizeof(msg_control); } #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) if (ls->sockaddr->sa_family == AF_INET6) { msg.msg_control = &msg_control6; msg.msg_controllen = sizeof(msg_control6); } #endif } #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, "recvmsg() not ready"); return; } ngx_log_error(NGX_LOG_ALERT, ev->log, err, "recvmsg() failed"); return; } #if (NGX_HAVE_MSGHDR_MSG_CONTROL) if (msg.msg_flags & (MSG_TRUNC|MSG_CTRUNC)) { ngx_log_error(NGX_LOG_ALERT, ev->log, 0, "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 (socklen == 0) { /* * on Linux recvmsg() returns zero msg_namelen * when receiving packets from unbound AF_UNIX sockets */ socklen = sizeof(struct sockaddr); ngx_memzero(&sa, sizeof(struct sockaddr)); sa.sockaddr.sa_family = ls->sockaddr->sa_family; } local_sockaddr = ls->sockaddr; local_socklen = ls->socklen; #if (NGX_HAVE_MSGHDR_MSG_CONTROL) 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_HAVE_IP_RECVDSTADDR) if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_RECVDSTADDR && local_sockaddr->sa_family == AF_INET) { struct in_addr *addr; struct sockaddr_in *sin; addr = (struct in_addr *) CMSG_DATA(cmsg); sin = (struct sockaddr_in *) local_sockaddr; sin->sin_addr = *addr; break; } #elif (NGX_HAVE_IP_PKTINFO) if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO && local_sockaddr->sa_family == AF_INET) { struct in_pktinfo *pkt; struct sockaddr_in *sin; pkt = (struct in_pktinfo *) CMSG_DATA(cmsg); sin = (struct sockaddr_in *) local_sockaddr; sin->sin_addr = pkt->ipi_addr; break; } #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) if (cmsg->cmsg_level == IPPROTO_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO && local_sockaddr->sa_family == AF_INET6) { struct in6_pktinfo *pkt6; struct sockaddr_in6 *sin6; pkt6 = (struct in6_pktinfo *) CMSG_DATA(cmsg); sin6 = (struct sockaddr_in6 *) local_sockaddr; sin6->sin6_addr = pkt6->ipi6_addr; break; } #endif } } #endif c = ngx_lookup_udp_connection(ls, sockaddr, socklen, 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, "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; rev = c->read; c->udp->buffer = &buf; 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_close_accepted_udp_connection(c); return; } c->sockaddr = ngx_palloc(c->pool, socklen); if (c->sockaddr == NULL) { ngx_close_accepted_udp_connection(c); return; } ngx_memcpy(c->sockaddr, sockaddr, socklen); log = ngx_palloc(c->pool, sizeof(ngx_log_t)); if (log == NULL) { ngx_close_accepted_udp_connection(c); return; } *log = ls->log; c->recv = ngx_udp_shared_recv; c->send = ngx_udp_send; c->send_chain = ngx_udp_send_chain; 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_close_accepted_udp_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_close_accepted_udp_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_close_accepted_udp_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_close_accepted_udp_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 recvmsg: %V fd:%d n:%z", c->number, &addr, c->fd, n); } } #endif if (ngx_insert_udp_connection(c) != NGX_OK) { ngx_close_accepted_udp_connection(c); return; } 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_close_accepted_udp_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 ssize_t ngx_udp_shared_recv(ngx_connection_t *c, u_char *buf, size_t size) { ssize_t n; ngx_buf_t *b; if (c->udp == NULL || c->udp->buffer == NULL) { return NGX_AGAIN; } b = c->udp->buffer; n = ngx_min(b->last - b->pos, (ssize_t) size); ngx_memcpy(buf, b->pos, n); c->udp->buffer = NULL; c->read->ready = 0; c->read->active = 1; return n; } void ngx_udp_rbtree_insert_value(ngx_rbtree_node_t *temp, ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel) { ngx_int_t rc; ngx_connection_t *c, *ct; ngx_rbtree_node_t **p; ngx_udp_connection_t *udp, *udpt; for ( ;; ) { if (node->key < temp->key) { p = &temp->left; } else if (node->key > temp->key) { p = &temp->right; } else { /* node->key == temp->key */ udp = (ngx_udp_connection_t *) node; c = udp->connection; udpt = (ngx_udp_connection_t *) temp; ct = udpt->connection; rc = ngx_cmp_sockaddr(c->sockaddr, c->socklen, ct->sockaddr, ct->socklen, 1); if (rc == 0 && c->listening->wildcard) { rc = ngx_cmp_sockaddr(c->local_sockaddr, c->local_socklen, ct->local_sockaddr, ct->local_socklen, 1); } p = (rc < 0) ? &temp->left : &temp->right; } if (*p == sentinel) { break; } temp = *p; } *p = node; node->parent = temp; node->left = sentinel; node->right = sentinel; ngx_rbt_red(node); } static ngx_int_t ngx_insert_udp_connection(ngx_connection_t *c) { uint32_t hash; ngx_pool_cleanup_t *cln; ngx_udp_connection_t *udp; if (c->udp) { return NGX_OK; } udp = ngx_pcalloc(c->pool, sizeof(ngx_udp_connection_t)); if (udp == NULL) { return NGX_ERROR; } udp->connection = c; ngx_crc32_init(hash); ngx_crc32_update(&hash, (u_char *) c->sockaddr, c->socklen); if (c->listening->wildcard) { ngx_crc32_update(&hash, (u_char *) c->local_sockaddr, c->local_socklen); } ngx_crc32_final(hash); udp->node.key = hash; cln = ngx_pool_cleanup_add(c->pool, 0); if (cln == NULL) { return NGX_ERROR; } cln->data = c; cln->handler = ngx_delete_udp_connection; ngx_rbtree_insert(&c->listening->rbtree, &udp->node); c->udp = udp; return NGX_OK; } void ngx_delete_udp_connection(void *data) { ngx_connection_t *c = data; if (c->udp == NULL) { return; } ngx_rbtree_delete(&c->listening->rbtree, &c->udp->node); c->udp = NULL; } static ngx_connection_t * ngx_lookup_udp_connection(ngx_listening_t *ls, struct sockaddr *sockaddr, socklen_t socklen, 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_udp_connection_t *udp; #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"); return NULL; } } #endif node = ls->rbtree.root; sentinel = ls->rbtree.sentinel; ngx_crc32_init(hash); ngx_crc32_update(&hash, (u_char *) sockaddr, socklen); if (ls->wildcard) { ngx_crc32_update(&hash, (u_char *) local_sockaddr, local_socklen); } ngx_crc32_final(hash); while (node != sentinel) { if (hash < node->key) { node = node->left; continue; } if (hash > node->key) { node = node->right; continue; } /* hash == node->key */ udp = (ngx_udp_connection_t *) node; c = udp->connection; rc = ngx_cmp_sockaddr(sockaddr, socklen, c->sockaddr, c->socklen, 1); if (rc == 0 && ls->wildcard) { rc = ngx_cmp_sockaddr(local_sockaddr, local_socklen, c->local_sockaddr, c->local_socklen, 1); } if (rc == 0) { return c; } node = (rc < 0) ? node->left : node->right; } return NULL; } #else void ngx_delete_udp_connection(void *data) { return; } #endif