1 files changed, 141 insertions, 0 deletions
diff --git a/modules/pam_filter/upperLOWER/upperLOWER.c b/modules/pam_filter/upperLOWER/upperLOWER.c
new file mode 100644
index 00000000..0ede4a0d
--- /dev/null
+++ b/modules/pam_filter/upperLOWER/upperLOWER.c
@@ -0,0 +1,141 @@
+/*
+ * This is a sample filter program, for use with pam_filter (a module
+ * provided with Linux-PAM). This filter simply transposes upper and
+ * lower case letters, it is intended for demonstration purposes and
+ * it serves no purpose other than to annoy the user...
+ */
+
+#include "config.h"
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "pam_filter.h"
+#include <security/pam_modutil.h>
+
+/* ---------------------------------------------------------------- */
+
+static void do_transpose(char *buffer,int len)
+{
+     int i;
+     for (i=0; i<len; ++i) {
+	  if (islower(buffer[i])) {
+	       buffer[i] = toupper(buffer[i]);
+	  } else {
+	       buffer[i] = tolower(buffer[i]);
+	  }
+     }
+}
+
+extern char **environ;
+
+int main(int argc, char **argv UNUSED)
+{
+     char buffer[BUFSIZ];
+     fd_set readers;
+     void (*before_user)(char *,int);
+     void (*before_app)(char *,int);
+
+     openlog("upperLOWER", LOG_CONS|LOG_PID, LOG_AUTHPRIV);
+
+#ifdef DEBUG
+     {
+	  int i;
+
+	  fprintf(stderr,"environment :[\r\n");
+	  for (i=0; environ[i]; ++i) {
+	       fprintf(stderr,"-> %s\r\n",environ[i]);
+	  }
+	  fprintf(stderr,"]: end\r\n");
+     }
+#endif
+
+     if (argc != 1) {
+#ifdef DEBUG
+	  fprintf(stderr,"filter invoked as conventional executable\n");
+#else
+	  syslog(LOG_ERR, "filter invoked as conventional executable");
+#endif
+	  exit(1);
+     }
+
+     before_user = before_app = do_transpose;   /* assign filter functions */
+
+     /* enter a loop that deals with the input and output of the
+        user.. passing it to and from the application */
+
+     FD_ZERO(&readers);                    /* initialize reading mask */
+
+     for (;;) {
+
+	  FD_SET(APPOUT_FILENO, &readers);              /* wake for output */
+	  FD_SET(APPERR_FILENO, &readers);               /* wake for error */
+	  FD_SET(STDIN_FILENO, &readers);                /* wake for input */
+
+	  if ( select(APPTOP_FILE,&readers,NULL,NULL,NULL) < 0 ) {
+#ifdef DEBUG
+	       fprintf(stderr,"select failed\n");
+#else
+	       syslog(LOG_WARNING,"select failed");
+#endif
+	       break;
+	  }
+
+	  /* application errors */
+
+	  if ( FD_ISSET(APPERR_FILENO,&readers) ) {
+	       int got = pam_modutil_read(APPERR_FILENO, buffer, BUFSIZ);
+	       if (got <= 0) {
+		    break;
+	       } else {
+		    /* translate to give to real terminal */
+		    if (before_user != NULL)
+			 before_user(buffer, got);
+		    if (pam_modutil_write(STDERR_FILENO, buffer, got) != got ) {
+			 syslog(LOG_WARNING,"couldn't write %d bytes?!",got);
+			 break;
+		    }
+	       }
+	  } else if ( FD_ISSET(APPOUT_FILENO,&readers) ) {    /* app output */
+	       int got = pam_modutil_read(APPOUT_FILENO, buffer, BUFSIZ);
+	       if (got <= 0) {
+		    break;
+	       } else {
+		    /* translate to give to real terminal */
+		    if (before_user != NULL)
+			 before_user(buffer, got);
+		    if (pam_modutil_write(STDOUT_FILENO, buffer, got) != got ) {
+			 syslog(LOG_WARNING,"couldn't write %d bytes!?",got);
+			 break;
+		    }
+	       }
+	  }
+
+	  if ( FD_ISSET(STDIN_FILENO, &readers) ) {  /* user input */
+	       int got = pam_modutil_read(STDIN_FILENO, buffer, BUFSIZ);
+	       if (got < 0) {
+		    syslog(LOG_WARNING,"user input junked");
+		    break;
+	       } else if (got) {
+		    /* translate to give to application */
+		    if (before_app != NULL)
+			 before_app(buffer, got);
+		    if (pam_modutil_write(APPIN_FILENO, buffer, got) != got ) {
+			 syslog(LOG_WARNING,"couldn't pass %d bytes!?",got);
+			 break;
+		    }
+	       } else {
+		    /* nothing received -- an error? */
+		    syslog(LOG_WARNING,"user input null?");
+		    break;
+	       }
+	  }
+     }
+
+     exit(0);
+}