Mercurial > hg > nginx
view src/os/unix/ngx_udp_sendmsg_chain.c @ 9236:d9a52ebb9b00
Mail: max_commands directive.
The directive specifies the maximum number of commands allowed during
authentication, after which the connection is closed. The default
limit is 1000, which is not expected to affect any well-behaving clients,
since authentication usually requires at most several commands, though
will effectively stop malicious clients from flooding the server with
with commands.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Sat, 30 Mar 2024 05:05:53 +0300 |
parents | af5adec171b4 |
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> static ngx_chain_t *ngx_udp_output_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *in, ngx_log_t *log); static ssize_t ngx_sendmsg_vec(ngx_connection_t *c, ngx_iovec_t *vec); ngx_chain_t * ngx_udp_unix_sendmsg_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { ssize_t n; off_t send; ngx_chain_t *cl; ngx_event_t *wev; ngx_iovec_t vec; struct iovec iovs[NGX_IOVS_PREALLOCATE]; wev = c->write; if (!wev->ready) { return in; } #if (NGX_HAVE_KQUEUE) if ((ngx_event_flags & NGX_USE_KQUEUE_EVENT) && wev->pending_eof) { (void) ngx_connection_error(c, wev->kq_errno, "kevent() reported about an closed connection"); wev->error = 1; return NGX_CHAIN_ERROR; } #endif /* the maximum limit size is the maximum size_t value - the page size */ if (limit == 0 || limit > (off_t) (NGX_MAX_SIZE_T_VALUE - ngx_pagesize)) { limit = NGX_MAX_SIZE_T_VALUE - ngx_pagesize; } send = 0; vec.iovs = iovs; vec.nalloc = NGX_IOVS_PREALLOCATE; for ( ;; ) { /* create the iovec and coalesce the neighbouring bufs */ cl = ngx_udp_output_chain_to_iovec(&vec, in, c->log); if (cl == NGX_CHAIN_ERROR) { return NGX_CHAIN_ERROR; } if (cl && cl->buf->in_file) { ngx_log_error(NGX_LOG_ALERT, c->log, 0, "file buf in sendmsg " "t:%d r:%d f:%d %p %p-%p %p %O-%O", cl->buf->temporary, cl->buf->recycled, cl->buf->in_file, cl->buf->start, cl->buf->pos, cl->buf->last, cl->buf->file, cl->buf->file_pos, cl->buf->file_last); ngx_debug_point(); return NGX_CHAIN_ERROR; } if (cl == in) { return in; } send += vec.size; n = ngx_sendmsg_vec(c, &vec); if (n == NGX_ERROR) { return NGX_CHAIN_ERROR; } if (n == NGX_AGAIN) { wev->ready = 0; return in; } c->sent += n; in = ngx_chain_update_sent(in, n); if (send >= limit || in == NULL) { return in; } } } static ngx_chain_t * ngx_udp_output_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *in, ngx_log_t *log) { size_t total, size; u_char *prev; ngx_uint_t n, flush; ngx_chain_t *cl; struct iovec *iov; cl = in; iov = NULL; prev = NULL; total = 0; n = 0; flush = 0; for ( /* void */ ; in && !flush; in = in->next) { if (in->buf->flush || in->buf->last_buf) { flush = 1; } if (ngx_buf_special(in->buf)) { continue; } if (in->buf->in_file) { break; } if (!ngx_buf_in_memory(in->buf)) { ngx_log_error(NGX_LOG_ALERT, log, 0, "bad buf in output chain " "t:%d r:%d f:%d %p %p-%p %p %O-%O", in->buf->temporary, in->buf->recycled, in->buf->in_file, in->buf->start, in->buf->pos, in->buf->last, in->buf->file, in->buf->file_pos, in->buf->file_last); ngx_debug_point(); return NGX_CHAIN_ERROR; } size = in->buf->last - in->buf->pos; if (prev == in->buf->pos) { iov->iov_len += size; } else { if (n == vec->nalloc) { ngx_log_error(NGX_LOG_ALERT, log, 0, "too many parts in a datagram"); return NGX_CHAIN_ERROR; } iov = &vec->iovs[n++]; iov->iov_base = (void *) in->buf->pos; iov->iov_len = size; } prev = in->buf->pos + size; total += size; } if (!flush) { #if (NGX_SUPPRESS_WARN) vec->size = 0; vec->count = 0; #endif return cl; } /* zero-sized datagram; pretend to have at least 1 iov */ if (n == 0) { iov = &vec->iovs[n++]; iov->iov_base = NULL; iov->iov_len = 0; } vec->count = n; vec->size = total; return in; } static ssize_t ngx_sendmsg_vec(ngx_connection_t *c, ngx_iovec_t *vec) { struct msghdr msg; #if (NGX_HAVE_ADDRINFO_CMSG) struct cmsghdr *cmsg; u_char msg_control[CMSG_SPACE(sizeof(ngx_addrinfo_t))]; #endif ngx_memzero(&msg, sizeof(struct msghdr)); if (c->socklen) { msg.msg_name = c->sockaddr; msg.msg_namelen = c->socklen; } msg.msg_iov = vec->iovs; msg.msg_iovlen = vec->count; #if (NGX_HAVE_ADDRINFO_CMSG) if (c->listening && c->listening->wildcard && c->local_sockaddr) { msg.msg_control = msg_control; msg.msg_controllen = sizeof(msg_control); ngx_memzero(msg_control, sizeof(msg_control)); cmsg = CMSG_FIRSTHDR(&msg); msg.msg_controllen = ngx_set_srcaddr_cmsg(cmsg, c->local_sockaddr); } #endif return ngx_sendmsg(c, &msg, 0); } #if (NGX_HAVE_ADDRINFO_CMSG) size_t ngx_set_srcaddr_cmsg(struct cmsghdr *cmsg, struct sockaddr *local_sockaddr) { size_t len; #if (NGX_HAVE_IP_SENDSRCADDR) struct in_addr *addr; struct sockaddr_in *sin; #elif (NGX_HAVE_IP_PKTINFO) struct in_pktinfo *pkt; struct sockaddr_in *sin; #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) struct in6_pktinfo *pkt6; struct sockaddr_in6 *sin6; #endif #if (NGX_HAVE_IP_SENDSRCADDR) || (NGX_HAVE_IP_PKTINFO) if (local_sockaddr->sa_family == AF_INET) { cmsg->cmsg_level = IPPROTO_IP; #if (NGX_HAVE_IP_SENDSRCADDR) cmsg->cmsg_type = IP_SENDSRCADDR; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr)); len = CMSG_SPACE(sizeof(struct in_addr)); sin = (struct sockaddr_in *) local_sockaddr; addr = (struct in_addr *) CMSG_DATA(cmsg); *addr = sin->sin_addr; #elif (NGX_HAVE_IP_PKTINFO) cmsg->cmsg_type = IP_PKTINFO; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo)); len = CMSG_SPACE(sizeof(struct in_pktinfo)); sin = (struct sockaddr_in *) local_sockaddr; pkt = (struct in_pktinfo *) CMSG_DATA(cmsg); ngx_memzero(pkt, sizeof(struct in_pktinfo)); pkt->ipi_spec_dst = sin->sin_addr; #endif return len; } #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) if (local_sockaddr->sa_family == AF_INET6) { cmsg->cmsg_level = IPPROTO_IPV6; cmsg->cmsg_type = IPV6_PKTINFO; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); len = CMSG_SPACE(sizeof(struct in6_pktinfo)); sin6 = (struct sockaddr_in6 *) local_sockaddr; pkt6 = (struct in6_pktinfo *) CMSG_DATA(cmsg); ngx_memzero(pkt6, sizeof(struct in6_pktinfo)); pkt6->ipi6_addr = sin6->sin6_addr; return len; } #endif return 0; } ngx_int_t ngx_get_srcaddr_cmsg(struct cmsghdr *cmsg, struct sockaddr *local_sockaddr) { #if (NGX_HAVE_IP_RECVDSTADDR) struct in_addr *addr; struct sockaddr_in *sin; #elif (NGX_HAVE_IP_PKTINFO) struct in_pktinfo *pkt; struct sockaddr_in *sin; #endif #if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO) struct in6_pktinfo *pkt6; struct sockaddr_in6 *sin6; #endif #if (NGX_HAVE_IP_RECVDSTADDR) if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_RECVDSTADDR && local_sockaddr->sa_family == AF_INET) { addr = (struct in_addr *) CMSG_DATA(cmsg); sin = (struct sockaddr_in *) local_sockaddr; sin->sin_addr = *addr; return NGX_OK; } #elif (NGX_HAVE_IP_PKTINFO) if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO && local_sockaddr->sa_family == AF_INET) { pkt = (struct in_pktinfo *) CMSG_DATA(cmsg); sin = (struct sockaddr_in *) local_sockaddr; sin->sin_addr = pkt->ipi_addr; return NGX_OK; } #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) { pkt6 = (struct in6_pktinfo *) CMSG_DATA(cmsg); sin6 = (struct sockaddr_in6 *) local_sockaddr; sin6->sin6_addr = pkt6->ipi6_addr; return NGX_OK; } #endif return NGX_DECLINED; } #endif ssize_t ngx_sendmsg(ngx_connection_t *c, struct msghdr *msg, int flags) { ssize_t n; ngx_err_t err; #if (NGX_DEBUG) size_t size; ngx_uint_t i; #endif eintr: n = sendmsg(c->fd, msg, flags); if (n == -1) { err = ngx_errno; switch (err) { case NGX_EAGAIN: ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "sendmsg() not ready"); return NGX_AGAIN; case NGX_EINTR: ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "sendmsg() was interrupted"); goto eintr; default: c->write->error = 1; ngx_connection_error(c, err, "sendmsg() failed"); return NGX_ERROR; } } #if (NGX_DEBUG) for (i = 0, size = 0; i < (size_t) msg->msg_iovlen; i++) { size += msg->msg_iov[i].iov_len; } ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "sendmsg: %z of %uz", n, size); #endif return n; }