--- 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);