1 files changed, 85 insertions, 0 deletions
diff --git a/try-from.c b/try-from.c
new file mode 100644
index 0000000..925e144
--- /dev/null
+++ b/try-from.c
@@ -0,0 +1,85 @@
+ /*
+  * This program can be called via a remote shell command to find out if the
+  * hostname and address are properly recognized, if username lookup works,
+  * and (SysV only) if the TLI on top of IP heuristics work.
+  * 
+  * Example: "rsh host /some/where/try-from".
+  * 
+  * Diagnostics are reported through syslog(3) and redirected to stderr.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+static char sccsid[] = "@(#) try-from.c 1.2 94/12/28 17:42:55";
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <string.h>
+
+#ifdef TLI
+#include <sys/tiuser.h>
+#include <stropts.h>
+#endif
+
+#ifndef STDIN_FILENO
+#define	STDIN_FILENO	0
+#endif
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+int     allow_severity = SEVERITY;	/* run-time adjustable */
+int     deny_severity = LOG_WARNING;	/* ditto */
+
+main(argc, argv)
+int     argc;
+char  **argv;
+{
+    struct request_info request;
+    char    buf[BUFSIZ];
+    char   *cp;
+
+    /*
+     * Simplify the process name, just like tcpd would.
+     */
+    if ((cp = strrchr(argv[0], '/')) != 0)
+	argv[0] = cp + 1;
+
+    /*
+     * Turn on the "IP-underneath-TLI" detection heuristics.
+     */
+#ifdef TLI
+    if (ioctl(0, I_FIND, "timod") == 0)
+	ioctl(0, I_PUSH, "timod");
+#endif /* TLI */
+
+    /*
+     * Look up the endpoint information.
+     */
+    request_init(&request, RQ_DAEMON, argv[0], RQ_FILE, STDIN_FILENO, 0);
+    (void) fromhost(&request);
+
+    /*
+     * Show some results. Name and address information is looked up when we
+     * ask for it.
+     */
+
+#define EXPAND(str) percent_x(buf, sizeof(buf), str, &request)
+
+    puts(EXPAND("client address  (%%a): %a"));
+    puts(EXPAND("client hostname (%%n): %n"));
+    puts(EXPAND("client username (%%u): %u"));
+    puts(EXPAND("client info     (%%c): %c"));
+    puts(EXPAND("server address  (%%A): %A"));
+    puts(EXPAND("server hostname (%%N): %N"));
+    puts(EXPAND("server process  (%%d): %d"));
+    puts(EXPAND("server info     (%%s): %s"));
+
+    return (0);
+}