X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/putty/blobdiff_plain/0c2986d033e11b811c34221a1fd4db3c9bc095e5..b8957e432baa265e13e3acc12faefd92c60c8a5f:/puttygen.c

diff --git a/puttygen.c b/puttygen.c
index 46815d6f..4fae90cd 100644
--- a/puttygen.c
+++ b/puttygen.c
@@ -5,10 +5,8 @@
 #include <windows.h>
 #include <commctrl.h>
 #include <time.h>
-#ifndef NO_SECURITY
-#include <aclapi.h>
-#endif
 #include <stdio.h>
+#include <stdlib.h>
 
 #define PUTTY_DO_GLOBALS
 
@@ -20,11 +18,6 @@
 
 #define DEFAULT_KEYSIZE 1024
 
-/*
- * TODO:
- *  - test the generated keys for actual working-RSA-key-hood
- */
-
 /* ----------------------------------------------------------------------
  * Progress report code. This is really horrible :-)
  */
@@ -322,13 +315,15 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
     static const char generating_msg[] =
         "Please wait while a key is generated...";
     static const char entropy_msg[] =
-        "Please move the mouse in this window to generate randomness";
+        "Please generate some randomness by moving the mouse over the blank area.";
     struct MainDlgState *state;
 
     switch (msg) {
       case WM_INITDIALOG:
         state = malloc(sizeof(*state));
         state->generation_thread_exists = FALSE;
+        state->collecting_entropy = FALSE;
+        state->entropy = NULL;
         state->key_exists = FALSE;
         SetWindowLong(hwnd, GWL_USERDATA, (LONG)state);
         {
@@ -370,9 +365,9 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
             staticbtn(&cp, "Save the generated key to a new file",
                       IDC_SAVESTATIC, "&Save", IDC_SAVE);
             endbox(&cp);
-            beginbox(&cp, "Actions",
-                     IDC_BOX_ACTIONS, IDC_BOXT_ACTIONS);
-            staticedit(&cp, "Length of generated keys in &bits:",
+            beginbox(&cp, "Parameters",
+                     IDC_BOX_PARAMS, IDC_BOXT_PARAMS);
+            staticedit(&cp, "Number of &bits in a generated key:",
 		       IDC_BITSSTATIC, IDC_BITS, 20);
             endbox(&cp);
         }
@@ -392,7 +387,9 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
 	return 1;
       case WM_MOUSEMOVE:
         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
-        if (state->collecting_entropy) {
+        if (state->collecting_entropy &&
+            state->entropy &&
+            state->entropy_got < state->entropy_required) {
             state->entropy[state->entropy_got++] = lParam;
             state->entropy[state->entropy_got++] = GetMessageTime();
             SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS,
@@ -407,6 +404,7 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
                 random_add_heavynoise(state->entropy, state->entropy_size);
                 memset(state->entropy, 0, state->entropy_size);
                 free(state->entropy);
+                state->collecting_entropy = FALSE;
 
                 SetDlgItemText(hwnd, IDC_GENERATING, generating_msg);
                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETRANGE, 0,
@@ -428,7 +426,6 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
                     free(params);
                 } else {
                     state->generation_thread_exists = TRUE;
-                    state->collecting_entropy = FALSE;
                 }
             }
         }
@@ -476,16 +473,18 @@ static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
 
                 /*
                  * My brief statistical tests on mouse movements
-                 * suggest that there are about 5 bits of
-                 * randomness in the x position, 5 in the y
+                 * suggest that there are about 2.5 bits of
+                 * randomness in the x position, 2.5 in the y
                  * position, and 1.7 in the message time, making
-                 * 11.7 bits of unpredictability per mouse
-                 * movement. However, other people have told me
-                 * it's far less than that, so I'm going to be
-                 * stupidly cautious and knock that down to a nice
-                 * round 4.
+                 * 5.7 bits of unpredictability per mouse movement.
+                 * However, other people have told me it's far less
+                 * than that, so I'm going to be stupidly cautious
+                 * and knock that down to a nice round 2. With this
+                 * method, we require two words per mouse movement,
+                 * so with 2 bits per mouse movement we expect 2
+                 * bits every 2 words.
                  */
-                state->entropy_required = (state->keysize / 4) * 2;
+                state->entropy_required = (state->keysize/2) * 2;
                 state->entropy_got = 0;
                 state->entropy_size = (state->entropy_required *
                                        sizeof(*state->entropy));