Introduce ID0 logging.

Stay as the invoking uid as much as possible.
Execution as a normal user is still forbidden for now,
so these changes are pretty ineffective.
The next commit will implement the modifications suggested
on -hackers a number of days ago.

1 files changed, 145 insertions, 0 deletions

diff --git a/usr.sbin/ppp/id.c b/usr.sbin/ppp/id.c
new file mode 100644
index 0000000..c37e5fe
--- /dev/null
+++ b/usr.sbin/ppp/id.c
@@ -0,0 +1,145 @@
+/*
+ * $Id: defs.c,v 1.1 1997/10/26 01:02:30 brian Exp $
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sysexits.h>
+#include <unistd.h>
+
+#include "mbuf.h"
+#include "log.h"
+#include "main.h"
+#ifdef __OpenBSD__
+#include <util.h>
+#else
+#include <libutil.h>
+#endif
+#include "id.h"
+
+static int uid;
+static int gid;
+static int euid;
+static int egid;
+
+void
+ID0init()
+{
+  uid = getuid();
+  gid = getgid();
+  euid = geteuid();
+  egid = getegid();
+}
+
+static void
+ID0setuser()
+{
+  if (setreuid(euid, uid) == -1) {
+    LogPrintf(LogERROR, "ID0setuser: Unable to setreuid!\n");
+    Cleanup(EX_NOPERM);
+  }
+}
+
+uid_t
+ID0realuid()
+{
+  return uid;
+}
+
+static void
+ID0set0()
+{
+  if (setreuid(uid, euid) == -1) {
+    LogPrintf(LogERROR, "ID0set0: Unable to setreuid!\n");
+    Cleanup(EX_NOPERM);
+  }
+}
+
+int
+ID0ioctl(int fd, unsigned long req, void *arg)
+{
+  int ret;
+
+  ID0set0();
+  ret = ioctl(fd, req, arg);
+  LogPrintf(LogID0, "%d = ioctl(%d, %d, %p)\n", ret, fd, req, arg);
+  ID0setuser();
+  return ret;
+}
+
+int
+ID0unlink(const char *name)
+{
+  int ret;
+
+  ID0set0();
+  ret = unlink(name);
+  LogPrintf(LogID0, "%d = unlink(\"%s\")\n", ret, name);
+  ID0setuser();
+  return ret;
+}
+
+int
+ID0socket(int domain, int type, int protocol)
+{
+  int ret;
+
+  ID0set0();
+  ret = socket(domain, type, protocol);
+  LogPrintf(LogID0, "%d = socket(%d, %d, %d)\n", ret, domain, type, protocol);
+  ID0setuser();
+  return ret;
+}
+
+FILE *
+ID0fopen(const char *path, const char *mode)
+{
+  FILE *ret;
+
+  ID0set0();
+  ret = fopen(path, mode);
+  LogPrintf(LogID0, "%p = fopen(\"%s\", \"%s\")\n", ret, path, mode);
+  ID0setuser();
+  return ret;
+}
+
+int
+ID0open(const char *path, int flags)
+{
+  int ret;
+
+  ID0set0();
+  ret = open(path, flags);
+  LogPrintf(LogID0, "%d = open(\"%s\", %d)\n", ret, path, flags);
+  ID0setuser();
+  return ret;
+}
+
+int
+ID0uu_lock(const char *ttyname)
+{
+  int ret;
+
+  ID0set0();
+  ret = uu_lock(ttyname);
+  LogPrintf(LogID0, "%d = uu_lock(\"%s\")\n", ret, ttyname);
+  ID0setuser();
+  return ret;
+}
+
+int
+ID0uu_unlock(const char *ttyname)
+{
+  int ret;
+
+  ID0set0();
+  ret = uu_unlock(ttyname);
+  LogPrintf(LogID0, "%d = uu_unlock(\"%s\")\n", ret, ttyname);
+  ID0setuser();
+  return ret;
+}