bugs...

[Zack Weinberg <zack@rabi.phys.columbia.edu>]

The script I just posted has a silly bug, insert a space after the
-u in "cvs diff -u" (inside the string).

The patch for SCM_CREDS also has some silly bugs.  A corrected version
is appended.

Finally, the Makefile patches I posted weeks ago have a number of
bugs; I will produce revised versions soon.  (These are the Makeconfig
and `make dist' changes.)

zw

1998-07-02 13:45 -0400  Zack Weinberg  <zack@rabi.phys.columbia.edu>

	BSD-style SCM_CREDS support.

	* sysdeps/unix/sysv/linux/socket.h: Define struct cmsgcred and
	SCM_CREDS.
	* sysdeps/unix/sysv/linux/sendmsg.c: New file.  Convert user
	visible SCM_CREDS packet to what the kernel wants.
	* sysdeps/unix/sysv/linux/recvmsg.c: New file.  Convert
	SCM_CREDS packet output by kernel to what users want.

	* sysdeps/unix/sysv/linux/sendmsg.S: Moved to...
	* sysdeps/unix/sysv/linux/__sendmsg.S: here.
	* sysdeps/unix/sysv/linux/recvmsg.S: Moved to...
	* sysdeps/unix/sysv/linux/__recvmsg.S: here.

	* sysdeps/unix/sysv/linux/Makefile [subdir=socket]: Add
	__sendmsg and __recvmsg to sysdep_routines.
	* sysdeps/unix/sysv/linux/Dist: Add __sendmsg.S and __recvmsg.S.

============================================================
Index: sysdeps/unix/sysv/linux/Makefile
--- sysdeps/unix/sysv/linux/Makefile	1998/06/30 12:18:07	1.79
+++ sysdeps/unix/sysv/linux/Makefile	1998/07/02 17:39:31
@@ -58,7 +58,7 @@
 sysdep_headers += net/if.h net/if_ppp.h net/ppp-comp.h \
 		  net/ppp_defs.h net/if_arp.h net/route.h net/ethernet.h \
 		  net/if_slip.h net/if_packet.h
-sysdep_routines += cmsg_nxthdr sa_len
+sysdep_routines += cmsg_nxthdr sa_len __sendmsg __recvmsg
 endif
 
 ifeq ($(subdir),sunrpc)
============================================================
Index: sysdeps/unix/sysv/linux/bits/socket.h
--- sysdeps/unix/sysv/linux/bits/socket.h	1998/05/15 09:06:14	1.17
+++ sysdeps/unix/sysv/linux/bits/socket.h	1998/07/02 17:39:31
@@ -222,12 +222,31 @@
    <linux/socket.h>.  */
 enum
   {
-    SCM_RIGHTS = 0x01,		/* Data array contains access rights.  */
+    SCM_RIGHTS = 0x01,		/* Transfer file descriptors.  */
 #define SCM_RIGHTS SCM_RIGHTS
-    __SCM_CREDENTIALS = 0x02,	/* Data array is `struct ucred'.  */
-    __SCM_CONNECT = 0x03	/* Data array is `struct scm_connect'.  */
+    SCM_CREDS = 0x02,		/* bsd-compatible credentials passing   */
+#define SCM_CREDS SCM_CREDS
+    __SCM_CONNECT = 0x03,	/* Data array is `struct scm_connect'.  */
+
   };
 
+#ifdef __USE_BSD /* ??? */
+
+/* User visible structure for SCM_CREDS message
+   (chosen for BSD source compatibility) */
+
+#define CMGROUP_MAX 16  /* Linux does not provide this info, so it doesn't
+			   matter... use what bsd does. */
+struct cmsgcred
+{
+    pid_t   cmcred_pid;             /* PID of sending process */
+    uid_t   cmcred_uid;             /* real UID of sending process */
+    uid_t   cmcred_euid;            /* effective UID of sending process */
+    gid_t   cmcred_gid;             /* real GID of sending process */
+    short   cmcred_ngroups;         /* number or groups */
+    gid_t   cmcred_groups[CMGROUP_MAX];     /* groups */
+};
+#endif
 
 /* Get socket manipulation related informations from kernel headers.  */
 #include <asm/socket.h>
============================================================
Index: sysdeps/unix/sysv/linux/recvmsg.c
--- sysdeps/unix/sysv/linux/recvmsg.c	created
+++ sysdeps/unix/sysv/linux/recvmsg.c	Wed Jul  1 08:50:27 1998	1.1
@@ -0,0 +1,91 @@
+/* Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sys/socket.h>
+#include <errno.h>
+#include <string.h>
+
+#include <asm/posix_types.h>
+
+/* The kernel expects this structure in SCM_CREDS messages.
+ * Note: sizeof(struct __kernel_ucred) <= sizeof(struct cmsgcred) must hold.
+ */
+struct __kernel_ucred
+{
+    __kernel_pid_t pid;
+    __kernel_uid_t uid;
+    __kernel_gid_t gid;
+};
+
+extern int __recvmsg (int, struct msghdr *, int);
+
+int
+recvmsg (fd, message, flags)
+     int fd;
+     struct msghdr *message;
+     int flags;
+{
+  struct cmsghdr *cm;
+  int ret;
+
+
+  /* Must check for space first. */
+  cm = CMSG_FIRSTHDR (message);
+  while (cm)
+    {
+      if (cm->cmsg_type == SCM_CREDS)
+	{
+	  if (cm->cmsg_len < CMSG_SPACE (sizeof (struct cmsgcred)))
+	    {
+	      __set_errno (EINVAL);
+	      return -1;
+	    }
+	}
+      cm = CMSG_NXTHDR (message, cm);
+    }
+
+
+  ret = __recvmsg (fd, message, flags);
+
+  if (ret == -1)
+    return ret;
+
+  /* Postprocess the message control block for SCM_CREDS. */
+  cm = CMSG_FIRSTHDR (message);
+  while (cm)
+    {
+      if (cm->cmsg_type == SCM_CREDS)
+	{
+	  struct cmsgcred *c = (struct cmsgcred *) CMSG_DATA (cm);
+	  struct __kernel_ucred u;
+	  int i;
+	  memcpy (&u, CMSG_DATA (cm), sizeof (struct __kernel_ucred));
+
+	  c->cmcred_pid = u.pid;
+	  c->cmcred_uid = u.uid;
+	  c->cmcred_gid = u.gid;
+
+	  c->cmcred_euid = -1;
+	  c->cmcred_ngroups = 0;
+	  for (i = 0; i < CMGROUP_MAX; i++)
+	    c->cmcred_groups[i] = -1;
+	}
+      cm = CMSG_NXTHDR (message, cm);
+    }
+  return ret;
+}
============================================================
Index: sysdeps/unix/sysv/linux/__recvmsg.S
--- sysdeps/unix/sysv/linux/__recvmsg.S	created
+++ sysdeps/unix/sysv/linux/__recvmsg.S	Thu Jul  2 13:25:41 1998	1.1
@@ -0,0 +1,5 @@
+#define	socket	__recvmsg
+#define	__socket __libc_recvmsg
+#define SOCKOP___recvmsg SOCKOP_recvmsg
+#define	NARGS	3
+#include <socket.S>
============================================================
Index: sysdeps/unix/sysv/linux/sendmsg.c
--- sysdeps/unix/sysv/linux/sendmsg.c	created
+++ sysdeps/unix/sysv/linux/sendmsg.c	Wed Jul  1 09:00:08 1998	1.1
@@ -0,0 +1,91 @@
+/* Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sys/socket.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <asm/posix_types.h>
+
+/* The kernel expects this structure in SCM_CREDS messages.
+ * Note: sizeof(struct __kernel_ucred) <= sizeof(struct cmsgcred) must hold.
+ */
+struct __kernel_ucred
+{
+    __kernel_pid_t pid;
+    __kernel_uid_t uid;
+    __kernel_gid_t gid;
+};
+
+extern int __sendmsg (int, const struct msghdr *, int);
+
+/* Send a message described by MESSAGE on socket FD.
+   Returns the number of bytes sent, or -1 for errors.  */
+int
+sendmsg (fd, message, flags)
+     int fd;
+     const struct msghdr *message;
+     int flags;
+{
+  struct cmsghdr *cm;
+  struct cmsgcred *cc;
+  struct __kernel_ucred *u;
+  pid_t pid;
+
+  /* Preprocess the message control block for SCM_CREDS. */
+  cm = CMSG_FIRSTHDR (message);
+  while (cm)
+    {
+      if (cm->cmsg_type == SCM_CREDS)
+	{
+	  if (cm->cmsg_len < CMSG_SPACE (sizeof (struct cmsgcred)))
+	    {
+	      __set_errno (EINVAL);
+	      return -1;
+	    }
+
+	  u = (struct __kernel_ucred *) CMSG_DATA (cm);
+	  cc = (struct cmsgcred *) CMSG_DATA(cm);
+	  /* Linux expects the calling process to pass in
+	     its credentials, and sanity checks them.
+	     You can send real, effective, or set- uid and gid.
+	     If the user hasn't filled in the buffer, we default to
+	     real uid and gid. */
+	  pid = getpid ();
+	  if (cc->cmcred_pid != pid)
+	  {
+	      u->pid = pid;
+	      u->uid = getuid ();
+	      u->gid = getgid ();
+	  }
+	  else
+	  {
+	      struct __kernel_ucred v;
+	      v.pid = cc->cmcred_pid;
+	      v.uid = cc->cmcred_uid;
+	      v.gid = cc->cmcred_gid;
+	      u->pid = v.pid;
+	      u->uid = v.uid;
+	      u->gid = v.gid;
+	  }
+	}
+      cm = CMSG_NXTHDR ((struct msghdr *)message, cm);
+    }
+
+  return __sendmsg (fd, message, flags);
+}
============================================================
Index: sysdeps/unix/sysv/linux/__sendmsg.S
--- sysdeps/unix/sysv/linux/__sendmsg.S	created
+++ sysdeps/unix/sysv/linux/__sendmsg.S	Thu Jul  2 13:25:21 1998	1.1
@@ -0,0 +1,6 @@
+#define	socket	__sendmsg
+#define	__socket __libc_sendmsg
+#define SOCKOP___sendmsg SOCKOP_sendmsg
+#define	NARGS	3
+#include <socket.S>
+
============================================================
Index: sysdeps/unix/sysv/linux/sendmsg.S
--- sysdeps/unix/sysv/linux/sendmsg.S	Tue Jun 30 22:12:54 1998	1.4
+++ sysdeps/unix/sysv/linux/sendmsg.S	removed
@@ -1,5 +0,0 @@
-#define	socket	sendmsg
-#define	__socket __libc_sendmsg
-#define	NARGS	3
-#include <socket.S>
-weak_alias (__libc_sendmsg, __sendmsg)
============================================================
Index: sysdeps/unix/sysv/linux/recvmsg.S
--- sysdeps/unix/sysv/linux/recvmsg.S	Tue Jun 30 22:12:54 1998	1.4
+++ sysdeps/unix/sysv/linux/recvmsg.S	removed
@@ -1,5 +0,0 @@
-#define	socket	recvmsg
-#define	__socket __libc_recvmsg
-#define	NARGS	3
-#include <socket.S>
-weak_alias (__libc_recvmsg, __recvmsg)
============================================================
Index: sysdeps/unix/sysv/linux/Dist
--- sysdeps/unix/sysv/linux/Dist	1998/05/08 15:01:39	1.50
+++ sysdeps/unix/sysv/linux/Dist	1998/07/02 17:45:34
@@ -74,3 +74,5 @@
 sys/vt.h
 xstatconv.c
 getdents64.c
+__sendmsg.S
+__recvmsg.S