* vbulletin captcha support.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/pwntcha/trunk@414 92316355-f0b4-4df1-b90c-862c8a59935f

Makefile.am

@@ -8,6 +8,7 @@ EXTRA_DIST = \
 	ChangeLog \
 	share/font_slashdot.png \
 	share/font_phpbb.png \
+	share/font_vbulletin.png \
 	$(NULL)
 
 AUTOMAKE_OPTIONS = dist-bzip2

src/Makefile.am

@@ -11,6 +11,7 @@ pwntcha_SOURCES = \
     phpbb.c \
     scode.c \
     slashdot.c \
+    vbulletin.c \
     test.c
 
 if USE_SDL

src/common.h

@@ -24,6 +24,7 @@ void dprintf(const char *fmt, ...);
 char *decode_phpbb(struct image *img);
 char *decode_scode(struct image *img);
 char *decode_slashdot(struct image *img);
+char *decode_vbulletin(struct image *img);
 char *decode_test(struct image *img);
 
 /* image operations */

src/main.c

@@ -130,6 +130,8 @@ int main(int argc, char *argv[])
             result = decode_scode(img);
         else if(!strcmp(mode, "slashdot"))
             result = decode_slashdot(img);
+        else if(!strcmp(mode, "vbulletin"))
+            result = decode_vbulletin(img);
         else
         {
             if(img->width == 320 && img->height == 50)
@@ -148,6 +150,11 @@ int main(int argc, char *argv[])
                 dprintf("autodetected slashdot captcha\n");
                 result = decode_slashdot(img);
             }
+            else if(img->height == 61)
+            {
+                dprintf("autodetected vbulletin captcha\n");
+                result = decode_vbulletin(img);
+            }
             else
             {
                 dprintf("could not guess captcha type\n");

src/vbulletin.c

@@ -0,0 +1,141 @@
+/*
+ * vbulletin.c: decode vbulletin captchas
+ * $Id$
+ *
+ * Copyright: (c) 2005 Sam Hocevar <sam@zoy.org>
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the Do What The Fuck You Want To
+ *   Public License as published by Banlu Kemiyatorn. See
+ *   http://sam.zoy.org/projects/COPYING.WTFPL for more details.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+#include "config.h"
+#include "common.h"
+
+#define FONTNAME "share/font_vbulletin.png"
+
+/* Main function */
+char *decode_vbulletin(struct image *img)
+{
+    char all[] = "2346789ABCDEFGHJKLMNPRTWXYZ";
+    char *result;
+    struct image *tmp1, *tmp2, *tmp3, *font;
+    int limits[6] = { 26, 53, 80, 107, 134, 160 };
+    int x, y, r, g, b, i, j;
+
+    font = image_load(FONTNAME);
+    if(!font)
+    {
+        fprintf(stderr, "cannot load font %s\n", FONTNAME);
+        exit(-1);
+    }
+
+    /* vBulletin captchas have 6 characters */
+    result = malloc(7 * sizeof(char));
+    strcpy(result, "      ");
+
+    /* half the captchas are inverse video; we set them back to normal */
+    getpixel(img, 0, 0, &r, &g, &b);
+    if(r < 50)
+        tmp1 = filter_equalize(img, 128);
+    else
+        tmp1 = filter_equalize(img, -128);
+
+    /* Remove garbage around the cells */
+    for(x = 0; x < img->width; x++)
+    {
+        for(y = 0; y < 15; y++)
+            setpixel(tmp1, x, y, 255, 255, 255);
+        for(y = 45; y < img->height; y++)
+            setpixel(tmp1, x, y, 255, 255, 255);
+    }
+
+    for(x = 0; x < img->width; x++)
+    {
+        for(i = 0; i < 6; i++)
+            if(x == limits[i])
+                break;
+        if(i == 6)
+            for(y = 15; y < 45; y++)
+                setpixel(tmp1, x, y, 255, 255, 255);
+        else
+            x += 11;
+    }
+
+    tmp2 = filter_black_stuff(tmp1);
+    tmp3 = filter_black_stuff(tmp2);
+
+    /* Fill letters in gray */
+    for(x = 26; x < 172; x++)
+    {
+        getpixel(tmp3, x, 15, &r, &g, &b);
+        if(r == 0)
+            filter_flood_fill(tmp3, x, 15, 127, 0, 255);
+    }
+
+    /* Find remaining black parts and remove them */
+    for(x = 26; x < 172; x++)
+        for(y = 15; y < 45; y++)
+        {
+            getpixel(tmp3, x, y, &r, &g, &b);
+            if(r == 0)
+                filter_flood_fill(tmp3, x, y, 255, 255, 255);
+        }
+
+    /* Fill letters in black */
+    for(x = 26; x < 172; x++)
+    {
+        getpixel(tmp3, x, 44, &r, &g, &b);
+        if(r == 127)
+            filter_flood_fill(tmp3, x, 44, 0, 0, 0);
+    }
+
+    /* Find remaining gray parts and remove them */
+    for(x = 26; x < 172; x++)
+        for(y = 15; y < 45; y++)
+        {
+            getpixel(tmp3, x, y, &r, &g, &b);
+            if(r == 127)
+                filter_flood_fill(tmp3, x, y, 255, 255, 255);
+        }
+
+    /* Guess all glyphs */
+    for(i = 0; i < 6; i++)
+    {
+        struct image *new;
+        int mindist = INT_MAX, min = -1;
+        new = filter_crop(tmp3, limits[i], 15, limits[i] + 11, 45);
+        for(j = 0; j < 27; j++)
+        {
+            int dist = 0;
+            for(y = 0; y < new->height; y++)
+                for(x = 0; x < new->width; x++)
+                {
+                    int r2, g2, b2;
+                    getpixel(font, 12 * j + x, y, &r, &g, &b);
+                    getpixel(new, x, y, &r2, &g2, &b2);
+                    dist += (r - r2) * (r - r2);
+                }
+            if(dist < mindist)
+            {
+                mindist = dist;
+                min = j;
+            }
+        }
+        image_free(new);
+        result[i] = all[min];
+    }
+
+    image_free(tmp1);
+    image_free(tmp2);
+    image_free(tmp3);
+    image_free(font);
+
+    return result;
+}
+