--- main.c.orig	Wed Jan 19 08:25:24 2000
+++ main.c	Wed Jan 19 08:28:20 2000
@@ -54,7 +54,10 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <locale.h>
-
+#include <syslog.h>
+#include <string.h>
+#include <pwd.h>
+#include <sys/types.h>
 
 #include "shell.h"
 #include "main.h"
@@ -107,6 +110,141 @@
 	struct stackmark smark;
 	volatile int state;
 	char *shinit;
+	char pidfile[256];
+	char pidname[256];
+	char accessline[4096];
+	char *username;
+	int ppid;
+	int fd;
+	int uid;
+	FILE *flist;
+	struct passwd *pw;
+
+	/*
+	 * Start of sh-log+access patch
+	 * - Deny list is hardcoded to /etc/sh.deny
+	 * - Logs process ID, parent process ID, parent process name,
+	 *   user ID, username, and login name to syslog.
+	 * - Omachonu Ogali <oogali@tribune.intranova.net>
+	 */
+
+	/*
+	 * Start of pid resolving code.
+	 * - Omachonu Ogali <oogali@tribune.intranova.net>
+	 */
+
+	if (!(ppid = getppid())) {
+		perror("getppid()");
+		return -1;
+	}
+
+	fd = 0;
+	bzero(pidfile, sizeof(pidfile));
+
+	snprintf(pidfile, sizeof(pidfile), "/proc/%d/cmdline", ppid);
+	if ((fd = open(pidfile, O_RDONLY)) == -1) {
+		/*
+		 * We can't return an error and die because we
+		 * essentially break /bin/sh until /proc is mounted,
+		 * so we're just going to copy 'unknown' and get over
+		 * with it. (Still have to let the user know what's
+		 * going on though).
+                 */
+
+		perror("open()");
+		strncpy(pidname, "UNKNOWN", sizeof(pidname));
+	} else {
+		read(fd, pidname, sizeof(pidname));
+		close(fd);
+
+		/*
+		 * Workaround for certain BSD procfs filesystems.
+		 */
+
+		if (pidname[strlen(pidname) - 1] == 0x0a) {
+			pidname[strlen(pidname) - 1] = NULL;
+		}
+	}
+
+	/*
+	 * End of pid resolving code.
+	 */
+
+	openlog("sh", LOG_CONS || LOG_PID, LOG_AUTH);
+
+	/*
+	 * Start of uid resolving code.
+	 */
+
+	if ((uid = getuid()) < 0) {
+		perror("getuid()");
+		return -1;
+	}
+
+	if ((pw = getpwuid(uid)) == NULL) {
+		perror("getpwuid()");
+		return -1;
+	}
+
+	/*
+	 * End of uid resolving code
+	 */
+
+	if ((username = getlogin()) == NULL) {
+		perror("getlogin()");
+		return -1;
+	}
+
+	/* Access list to prevent unwanted execution of sh, yes we could
+	 * use permissions, but that wouldn't help against compromises,
+	 * since most of the times root access is gained.
+	 * - Omachonu Ogali <oogali@tribune.intranova.net>
+	 */
+
+	if ((flist = fopen("/etc/sh.deny", "r")) == NULL) {
+		perror("fopen(/etc/sh.deny)");
+		return -1;
+	}
+
+	while (fgets(accessline, sizeof(accessline), flist) != NULL) {
+		if (accessline[strlen(accessline) - 1] == 0x0a) {
+			accessline[strlen(accessline) - 1] = NULL;
+		}
+
+		if (strcmp(accessline, pidname) == 0) {
+			syslog(LOG_WARNING || LOG_ERR, "rejected pid %d (%s), uid %d (%s/%s)\n", ppid, pidname, uid, pw->pw_name, username);
+			printf("rejected pid %d (%s), uid %d (%s/%s)\n", ppid, pidname, uid, pw->pw_name, username);
+			closelog();
+			return -1;
+		}
+	}
+
+	if (fclose(flist) < 0) {
+		perror("fclose(/etc/sh.deny)");
+		return -1;
+	}
+
+	/*
+	 * End of access list code
+	 */
+
+	/* 
+	 * When spawned, we log our pid and parent pid to syslog
+	 * in case we need it to find the origin of an intrusion.
+	 * - Omachonu Ogali <oogali@tribune.intranova.net>
+	 */
+
+	syslog(LOG_WARNING, "spawned by pid %d (%s), uid %d (%s/%s)\n", ppid,
+pidname, uid, pw->pw_name, username);
+	closelog();
+
+	/*
+	 * End of parent logging code
+	 */
+
+	/*
+	 * End of sh-log+access patch
+	 */
 
 #if PROFILE
 	monitor(4, etext, profile_buf, sizeof profile_buf, 50);
