Mercurial > hg > nginx
view src/event/ngx_event_udp.c @ 8077:ec1fa010c3a5
SSL: explicit session id length checking.
Session ids are not expected to be longer than 32 bytes, but this is
theoretically possible with TLSv1.3, where session ids are essentially
arbitrary and sent as session tickets. Since on 64-bit platforms we
use fixed 32-byte buffer for session ids, added an explicit length check
to make sure the buffer is large enough.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 12 Oct 2022 20:14:39 +0300 |
parents | 32b0ba4855a6 |
children | 3108d4d668e4 ce6d9cf0f567 |
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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_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, "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, "recvmsg() not ready"); return; } ngx_log_error(NGX_LOG_ALERT, ev->log, err, "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, "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_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 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->need_flush_buf = 1; 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