Mercurial > hg > nginx
view src/event/ngx_event_connect.c @ 7119:fef61d26da39
Fixed buffer overread with unix sockets after accept().
Some OSes (notably macOS, NetBSD, and Solaris) allow unix socket addresses
larger than struct sockaddr_un. Moreover, some of them (macOS, Solaris)
return socklen of the socket address before it was truncated to fit the
buffer provided. As such, on these systems socklen must not be used without
additional check that it is within the buffer provided.
Appropriate checks added to ngx_event_accept() (after accept()),
ngx_event_recvmsg() (after recvmsg()), and ngx_set_inherited_sockets()
(after getsockname()).
We also obtain socket addresses via getsockname() in
ngx_connection_local_sockaddr(), but it does not need any checks as
it is only used for INET and INET6 sockets (as there can be no
wildcard unix sockets).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 04 Oct 2017 21:19:33 +0300 |
parents | 56fc55e32f23 |
children | 8b70d4caa505 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_event_connect.h> #if (NGX_HAVE_TRANSPARENT_PROXY) static ngx_int_t ngx_event_connect_set_transparent(ngx_peer_connection_t *pc, ngx_socket_t s); #endif ngx_int_t ngx_event_connect_peer(ngx_peer_connection_t *pc) { int rc, type; #if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT || NGX_LINUX) in_port_t port; #endif ngx_int_t event; ngx_err_t err; ngx_uint_t level; ngx_socket_t s; ngx_event_t *rev, *wev; ngx_connection_t *c; rc = pc->get(pc, pc->data); if (rc != NGX_OK) { return rc; } type = (pc->type ? pc->type : SOCK_STREAM); s = ngx_socket(pc->sockaddr->sa_family, type, 0); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, pc->log, 0, "%s socket %d", (type == SOCK_STREAM) ? "stream" : "dgram", s); if (s == (ngx_socket_t) -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, ngx_socket_n " failed"); return NGX_ERROR; } c = ngx_get_connection(s, pc->log); if (c == NULL) { if (ngx_close_socket(s) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, ngx_close_socket_n "failed"); } return NGX_ERROR; } c->type = type; if (pc->rcvbuf) { if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, (const void *) &pc->rcvbuf, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(SO_RCVBUF) failed"); goto failed; } } if (ngx_nonblocking(s) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, ngx_nonblocking_n " failed"); goto failed; } if (pc->local) { #if (NGX_HAVE_TRANSPARENT_PROXY) if (pc->transparent) { if (ngx_event_connect_set_transparent(pc, s) != NGX_OK) { goto failed; } } #endif #if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT || NGX_LINUX) port = ngx_inet_get_port(pc->local->sockaddr); #endif #if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT) if (pc->sockaddr->sa_family != AF_UNIX && port == 0) { static int bind_address_no_port = 1; if (bind_address_no_port) { if (setsockopt(s, IPPROTO_IP, IP_BIND_ADDRESS_NO_PORT, (const void *) &bind_address_no_port, sizeof(int)) == -1) { err = ngx_socket_errno; if (err != NGX_EOPNOTSUPP && err != NGX_ENOPROTOOPT) { ngx_log_error(NGX_LOG_ALERT, pc->log, err, "setsockopt(IP_BIND_ADDRESS_NO_PORT) " "failed, ignored"); } else { bind_address_no_port = 0; } } } } #endif #if (NGX_LINUX) if (pc->type == SOCK_DGRAM && port != 0) { int reuse_addr = 1; if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const void *) &reuse_addr, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(SO_REUSEADDR) failed"); goto failed; } } #endif if (bind(s, pc->local->sockaddr, pc->local->socklen) == -1) { ngx_log_error(NGX_LOG_CRIT, pc->log, ngx_socket_errno, "bind(%V) failed", &pc->local->name); goto failed; } } if (type == SOCK_STREAM) { c->recv = ngx_recv; c->send = ngx_send; c->recv_chain = ngx_recv_chain; c->send_chain = ngx_send_chain; c->sendfile = 1; if (pc->sockaddr->sa_family == AF_UNIX) { c->tcp_nopush = NGX_TCP_NOPUSH_DISABLED; c->tcp_nodelay = NGX_TCP_NODELAY_DISABLED; #if (NGX_SOLARIS) /* Solaris's sendfilev() supports AF_NCA, AF_INET, and AF_INET6 */ c->sendfile = 0; #endif } } else { /* type == SOCK_DGRAM */ c->recv = ngx_udp_recv; c->send = ngx_send; c->send_chain = ngx_udp_send_chain; } c->log_error = pc->log_error; rev = c->read; wev = c->write; rev->log = pc->log; wev->log = pc->log; pc->connection = c; c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1); if (ngx_add_conn) { if (ngx_add_conn(c) == NGX_ERROR) { goto failed; } } ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connect to %V, fd:%d #%uA", pc->name, s, c->number); rc = connect(s, pc->sockaddr, pc->socklen); if (rc == -1) { err = ngx_socket_errno; if (err != NGX_EINPROGRESS #if (NGX_WIN32) /* Winsock returns WSAEWOULDBLOCK (NGX_EAGAIN) */ && err != NGX_EAGAIN #endif ) { if (err == NGX_ECONNREFUSED #if (NGX_LINUX) /* * Linux returns EAGAIN instead of ECONNREFUSED * for unix sockets if listen queue is full */ || err == NGX_EAGAIN #endif || err == NGX_ECONNRESET || err == NGX_ENETDOWN || err == NGX_ENETUNREACH || err == NGX_EHOSTDOWN || err == NGX_EHOSTUNREACH) { level = NGX_LOG_ERR; } else { level = NGX_LOG_CRIT; } ngx_log_error(level, c->log, err, "connect() to %V failed", pc->name); ngx_close_connection(c); pc->connection = NULL; return NGX_DECLINED; } } if (ngx_add_conn) { if (rc == -1) { /* NGX_EINPROGRESS */ return NGX_AGAIN; } ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected"); wev->ready = 1; return NGX_OK; } if (ngx_event_flags & NGX_USE_IOCP_EVENT) { ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, ngx_socket_errno, "connect(): %d", rc); if (ngx_blocking(s) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, ngx_blocking_n " failed"); goto failed; } /* * FreeBSD's aio allows to post an operation on non-connected socket. * NT does not support it. * * TODO: check in Win32, etc. As workaround we can use NGX_ONESHOT_EVENT */ rev->ready = 1; wev->ready = 1; return NGX_OK; } if (ngx_event_flags & NGX_USE_CLEAR_EVENT) { /* kqueue */ event = NGX_CLEAR_EVENT; } else { /* select, poll, /dev/poll */ event = NGX_LEVEL_EVENT; } if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) { goto failed; } if (rc == -1) { /* NGX_EINPROGRESS */ if (ngx_add_event(wev, NGX_WRITE_EVENT, event) != NGX_OK) { goto failed; } return NGX_AGAIN; } ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected"); wev->ready = 1; return NGX_OK; failed: ngx_close_connection(c); pc->connection = NULL; return NGX_ERROR; } #if (NGX_HAVE_TRANSPARENT_PROXY) static ngx_int_t ngx_event_connect_set_transparent(ngx_peer_connection_t *pc, ngx_socket_t s) { int value; value = 1; #if defined(SO_BINDANY) if (setsockopt(s, SOL_SOCKET, SO_BINDANY, (const void *) &value, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(SO_BINDANY) failed"); return NGX_ERROR; } #else switch (pc->local->sockaddr->sa_family) { case AF_INET: #if defined(IP_TRANSPARENT) if (setsockopt(s, IPPROTO_IP, IP_TRANSPARENT, (const void *) &value, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(IP_TRANSPARENT) failed"); return NGX_ERROR; } #elif defined(IP_BINDANY) if (setsockopt(s, IPPROTO_IP, IP_BINDANY, (const void *) &value, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(IP_BINDANY) failed"); return NGX_ERROR; } #endif break; #if (NGX_HAVE_INET6) case AF_INET6: #if defined(IPV6_TRANSPARENT) if (setsockopt(s, IPPROTO_IPV6, IPV6_TRANSPARENT, (const void *) &value, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(IPV6_TRANSPARENT) failed"); return NGX_ERROR; } #elif defined(IPV6_BINDANY) if (setsockopt(s, IPPROTO_IPV6, IPV6_BINDANY, (const void *) &value, sizeof(int)) == -1) { ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno, "setsockopt(IPV6_BINDANY) failed"); return NGX_ERROR; } #endif break; #endif /* NGX_HAVE_INET6 */ } #endif /* SO_BINDANY */ return NGX_OK; } #endif ngx_int_t ngx_event_get_peer(ngx_peer_connection_t *pc, void *data) { return NGX_OK; }