Wir kehren zurueck zu Kudzu, da hwinfo noch mehr Aerger macht.

[people/teissler/ipfire-2.x.git] / src / patches / sysklogd-1.4.1-caen-owl-klogd-drop-root.diff

diff -ur sysklogd-1.4.1.orig/klogd.8 sysklogd-1.4.1/klogd.8
--- sysklogd-1.4.1.orig/klogd.8	Sun Mar 11 22:35:51 2001
+++ sysklogd-1.4.1/klogd.8	Mon Oct  8 09:50:50 2001
@@ -3,8 +3,9 @@
 .\" Sun Jul 30 01:35:55 MET: Martin Schulze: Updates
 .\" Sun Nov 19 23:22:21 MET: Martin Schulze: Updates
 .\" Mon Aug 19 09:42:08 CDT 1996: Dr. G.W. Wettstein: Updates
+.\" Thu Feb 17 2000: Chris Wing: Unprivileged klogd feature
 .\"
-.TH KLOGD 8 "21 August, 1999" "Version 1.4" "Linux System Administration"
+.TH KLOGD 8 "8 October, 2001" "Version 1.4.1+CAEN/OW" "Linux System Administration"
 .SH NAME
 klogd \- Kernel Log Daemon
 .LP
@@ -17,6 +18,12 @@
 .RB [ " \-f "
 .I fname
 ]
+.RB [ " \-u "
+.I username
+]
+.RB [ " \-j "
+.I chroot_dir
+]
 .RB [ " \-iI " ]
 .RB [ " \-n " ]
 .RB [ " \-o " ]
@@ -45,6 +52,20 @@
 .TP
 .BI "\-f " file
 Log messages to the specified filename rather than to the syslog facility.
+.TP
+.BI "\-u " username
+Tells klogd to become the specified user and drop root privileges before
+starting logging.
+.TP
+.BI "\-j " chroot_dir
+Tells klogd to
+.BR chroot (2)
+into this directory after initializing.
+This option is only valid if the \-u option is also used to run klogd
+without root privileges.
+Note that the use of this option will prevent \-i and \-I from working
+unless you set up the chroot directory in such a way that klogd can still
+read the kernel module symbols.
 .TP
 .BI "\-i \-I"
 Signal the currently executing klogd daemon.  Both of these switches control
diff -ur sysklogd-1.4.1.orig/klogd.c sysklogd-1.4.1/klogd.c
--- sysklogd-1.4.1.orig/klogd.c	Sun Mar 11 22:40:10 2001
+++ sysklogd-1.4.1/klogd.c	Mon Oct  8 09:52:06 2001
@@ -258,6 +258,8 @@
 #include <stdarg.h>
 #include <paths.h>
 #include <stdlib.h>
+#include <pwd.h>
+#include <grp.h>
 #include "klogd.h"
 #include "ksyms.h"
 #ifndef TESTING
@@ -308,6 +310,9 @@
 int debugging = 0;
 int symbols_twice = 0;
 
+char *server_user = NULL;
+char *chroot_dir = NULL;
+int log_flags = 0;
 
 /* Function prototypes. */
 extern int ksyslog(int type, char *buf, int len);
@@ -528,8 +533,9 @@
 	 * First do a stat to determine whether or not the proc based
 	 * file system is available to get kernel messages from.
 	 */
-	if ( use_syscall ||
-	    ((stat(_PATH_KLOG, &sb) < 0) && (errno == ENOENT)) )
+	if (!server_user &&
+	    (use_syscall ||
+	    ((stat(_PATH_KLOG, &sb) < 0) && (errno == ENOENT))))
 	{
 	  	/* Initialize kernel logging. */
 	  	ksyslog(1, NULL, 0);
@@ -977,6 +983,27 @@
 }
 
 
+static int drop_root(void)
+{
+	struct passwd *pw;
+
+	if (!(pw = getpwnam(server_user))) return -1;
+
+	if (!pw->pw_uid) return -1;
+
+	if (chroot_dir) {
+		if (chroot(chroot_dir)) return -1;
+		if (chdir("/")) return -1;
+	}
+
+	if (setgroups(0, NULL)) return -1;
+	if (setgid(pw->pw_gid)) return -1;
+	if (setuid(pw->pw_uid)) return -1;
+
+	return 0;
+}
+
+
 int main(argc, argv)
 
 	int argc;
@@ -994,7 +1021,7 @@
 	chdir ("/");
 #endif
 	/* Parse the command-line. */
-	while ((ch = getopt(argc, argv, "c:df:iIk:nopsvx2")) != EOF)
+	while ((ch = getopt(argc, argv, "c:df:u:j:iIk:nopsvx2")) != EOF)
 		switch((char)ch)
 		{
 		    case '2':		/* Print lines with symbols twice. */
@@ -1016,6 +1043,10 @@
 		    case 'I':
 			SignalDaemon(SIGUSR2);
 			return(0);
+		    case 'j':		/* chroot 'j'ail */
+			chroot_dir = optarg;
+			log_flags |= LOG_NDELAY;
+			break;
 		    case 'k':		/* Kernel symbol file. */
 			symfile = optarg;
 			break;
@@ -1031,6 +1062,9 @@
 		    case 's':		/* Use syscall interface. */
 			use_syscall = 1;
 			break;
+		    case 'u':		/* Run as this user */
+			server_user = optarg;
+			break;
 		    case 'v':
 			printf("klogd %s.%s\n", VERSION, PATCHLEVEL);
 			exit (1);
@@ -1039,6 +1073,10 @@
 			break;
 		}
 
+	if (chroot_dir && !server_user) {
+		fputs("'-j' is only valid with '-u'", stderr);
+		exit(1);
+	}
 
 	/* Set console logging level. */
 	if ( log_level != (char *) 0 )
@@ -1136,7 +1174,7 @@
 		}
 	}
 	else
-		openlog("kernel", 0, LOG_KERN);
+		openlog("kernel", log_flags, LOG_KERN);
 
 
 	/* Handle one-shot logging. */
@@ -1161,4 +1199,9 @@
 		}
 	}
+
+	if (server_user && drop_root()) {
+		syslog(LOG_ALERT, "klogd: failed to drop root");
+		Terminate();
+	}
 
         /* The main loop. */