- djm@cvs.openbsd.org 2010/01/30 02:54:53

[openssh.git] / monitor_fdpass.c

diff --git a/monitor_fdpass.c b/monitor_fdpass.c
index 7785535bb8e9583aae07dc16b7b8fb2c53903911..7eb6f5c6e1f3ffe7a561a0bd48ef65d9deccadb0 100644 (file)
--- a/monitor_fdpass.c
+++ b/monitor_fdpass.c
@@ -1,3 +1,4 @@
+/* $OpenBSD: monitor_fdpass.c,v 1.19 2010/01/12 00:58:25 djm Exp $ */
 /*
  * Copyright 2001 Niels Provos <provos@citi.umich.edu>
  * All rights reserved.
@@ -24,63 +25,158 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: monitor_fdpass.c,v 1.1 2002/03/18 17:27:22 provos Exp $");
 
+#include <sys/types.h>
+#include <sys/socket.h>
 #include <sys/uio.h>
+#ifdef HAVE_SYS_UN_H
+#include <sys/un.h>
+#endif
+
+#include <errno.h>
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
+#include <string.h>
+#include <stdarg.h>
 
 #include "log.h"
 #include "monitor_fdpass.h"
 
-void
-mm_send_fd(int socket, int fd)
+int
+mm_send_fd(int sock, int fd)
 {
+#if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR))
        struct msghdr msg;
-       char tmp[CMSG_SPACE(sizeof(int))];
+#ifndef HAVE_ACCRIGHTS_IN_MSGHDR
+       union {
+               struct cmsghdr hdr;
+               char buf[CMSG_SPACE(sizeof(int))];
+       } cmsgbuf;
        struct cmsghdr *cmsg;
+#endif
        struct iovec vec;
-       char ch;
+       char ch = '\0';
+       ssize_t n;
+       struct pollfd pfd;
 
        memset(&msg, 0, sizeof(msg));
-       msg.msg_control = (caddr_t)tmp;
-       msg.msg_controllen = CMSG_LEN(sizeof(int));
+#ifdef HAVE_ACCRIGHTS_IN_MSGHDR
+       msg.msg_accrights = (caddr_t)&fd;
+       msg.msg_accrightslen = sizeof(fd);
+#else
+       msg.msg_control = (caddr_t)&cmsgbuf.buf;
+       msg.msg_controllen = sizeof(cmsgbuf.buf);
        cmsg = CMSG_FIRSTHDR(&msg);
        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
        cmsg->cmsg_level = SOL_SOCKET;
        cmsg->cmsg_type = SCM_RIGHTS;
        *(int *)CMSG_DATA(cmsg) = fd;
+#endif
 
        vec.iov_base = &ch;
        vec.iov_len = 1;
        msg.msg_iov = &vec;
        msg.msg_iovlen = 1;
 
-       if (sendmsg(socket, &msg, 0) == -1)
-               fatal("%s: sendmsg(%d)", __FUNCTION__, fd);
+       pfd.fd = sock;
+       pfd.events = POLLOUT;
+       while ((n = sendmsg(sock, &msg, 0)) == -1 &&
+           (errno == EAGAIN || errno == EINTR)) {
+               debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno));
+               (void)poll(&pfd, 1, -1);
+       }
+       if (n == -1) {
+               error("%s: sendmsg(%d): %s", __func__, fd,
+                   strerror(errno));
+               return -1;
+       }
+
+       if (n != 1) {
+               error("%s: sendmsg: expected sent 1 got %ld",
+                   __func__, (long)n);
+               return -1;
+       }
+       return 0;
+#else
+       error("%s: file descriptor passing not supported", __func__);
+       return -1;
+#endif
 }
 
 int
-mm_receive_fd(int socket)
+mm_receive_fd(int sock)
 {
+#if defined(HAVE_RECVMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR))
        struct msghdr msg;
-       char tmp[CMSG_SPACE(sizeof(int))];
+#ifndef HAVE_ACCRIGHTS_IN_MSGHDR
+       union {
+               struct cmsghdr hdr;
+               char buf[CMSG_SPACE(sizeof(int))];
+       } cmsgbuf;
        struct cmsghdr *cmsg;
+#endif
        struct iovec vec;
+       ssize_t n;
        char ch;
+       int fd;
+       struct pollfd pfd;
 
        memset(&msg, 0, sizeof(msg));
        vec.iov_base = &ch;
        vec.iov_len = 1;
        msg.msg_iov = &vec;
        msg.msg_iovlen = 1;
-       msg.msg_control = tmp;
-       msg.msg_controllen = sizeof(tmp);
+#ifdef HAVE_ACCRIGHTS_IN_MSGHDR
+       msg.msg_accrights = (caddr_t)&fd;
+       msg.msg_accrightslen = sizeof(fd);
+#else
+       msg.msg_control = &cmsgbuf.buf;
+       msg.msg_controllen = sizeof(cmsgbuf.buf);
+#endif
+
+       pfd.fd = sock;
+       pfd.events = POLLIN;
+       while ((n = recvmsg(sock, &msg, 0)) == -1 &&
+           (errno == EAGAIN || errno == EINTR)) {
+               debug3("%s: recvmsg: %s", __func__, strerror(errno));
+               (void)poll(&pfd, 1, -1);
+       }
+       if (n == -1) {
+               error("%s: recvmsg: %s", __func__, strerror(errno));
+               return -1;
+       }
 
-       if (recvmsg(socket, &msg, 0) == -1)
-               fatal("%s: recvmsg", __FUNCTION__);
+       if (n != 1) {
+               error("%s: recvmsg: expected received 1 got %ld",
+                   __func__, (long)n);
+               return -1;
+       }
 
+#ifdef HAVE_ACCRIGHTS_IN_MSGHDR
+       if (msg.msg_accrightslen != sizeof(fd)) {
+               error("%s: no fd", __func__);
+               return -1;
+       }
+#else
        cmsg = CMSG_FIRSTHDR(&msg);
-       if (cmsg->cmsg_type != SCM_RIGHTS)
-               fatal("%s: expected type %d got %d", __FUNCTION__,
+       if (cmsg == NULL) {
+               error("%s: no message header", __func__);
+               return -1;
+       }
+
+#ifndef BROKEN_CMSG_TYPE
+       if (cmsg->cmsg_type != SCM_RIGHTS) {
+               error("%s: expected type %d got %d", __func__,
                    SCM_RIGHTS, cmsg->cmsg_type);
-       return (*(int *)CMSG_DATA(cmsg));
+               return -1;
+       }
+#endif
+       fd = (*(int *)CMSG_DATA(cmsg));
+#endif
+       return fd;
+#else
+       error("%s: file descriptor passing not supported", __func__);
+       return -1;
+#endif
 }