add captcha validation (realperson lib)

cgi-bin/comex_merci_pour_les_infos.py.cgi

@@ -12,13 +12,40 @@ __status__    = "Test"
 
 from cgi         import FieldStorage
 from traceback   import format_tb
+from ctypes      import c_int
 
 # debug
 import cgitb
 cgitb.enable()
 
 
+########### SUBS ###########
+def re_hash(userinput, salt=""):
+    """
+    Build the captcha's verification hash server side
+    (my rewrite of keith-wood.name/realPerson.html python's version)
+    """
+    hashk = 5381
+
+    value = userinput.upper() + salt
+    for i, char in enumerate(value):
+
+        hashk = c_int( ((hashk << 5) + hashk + ord(char)) & 0xFFFFFFFF ).value
+        # bitwise masks 0xFFFFFFFF to go back to int32 each time
+        # c_int( previous ).value to go from unsigned ints to c signed ints each time
+
+        # debug iterations
+        # print(i, hashk, '<br/>')
+
+    return hashk
+
+
+########### MAIN ###########
 if __name__ == "__main__":
+    # any response must have this
+    print("Content-type: text/html")
+    print()  # blank line <=> end of headers
+
     # reception: the cgi library gets vars from html form within received http POST
     this_data = FieldStorage()
 
@@ -39,21 +66,31 @@ if __name__ == "__main__":
         keywordsss  = this_data['keywords'].value   # single string but ','-separated
         # keywordzzz = this_data.getlist(keywords)   # array
 
-        # todo
+        #  --------- todo ------>8--------------
         # institution = this_data[].value
 
         # optional
         # picture = form["user_picture"]
         # if picture.file & picture.filename:
         #     picture_bytes = picture.value
+        # --------------------->8---------------
+
+        # for captcha validation -----------------------------------------------
+        form_accepted = False
+        captcha_userinput = this_data['my-captcha'].value
+        captcha_verifhash = int(this_data['my-captchaHash'].value)
+        captcha_userhash = re_hash(captcha_userinput)
+        form_accepted = (captcha_userhash == captcha_verifhash)
+        # ----------------------------------------------------------------------
 
-        # response
-        print("Content-type: text/html")
-        print()  # blank line <=> end of headers
 
+        # debug data keys
+        # print([k for k in this_data])
+
+        # show received values
         print("<TITLE>CGI script output</TITLE>")
-        print([k for k in this_data])
-        #
+
+        print("<p style='font-family:Calibri, sans-serif; font-size:80%'")
         print('<br>first_name:',first_name)
         print('<br>midle_name:',middle_name)
         print('<br>last_name:',last_name)
@@ -62,19 +99,16 @@ if __name__ == "__main__":
         print('<br>country:',country)
         print('<br>jobtitle:',jobtitle)
         print('<br>keywords:',keywordsss)
+        print('<br>captcha is correct ?:',form_accepted)
         # print('instituton:',institution)
 
     except KeyError as kerrr:
-        print("Content-type: text/html")
-        print()  # blank line <=> end of headers
         print("<h3>Your form was empty</h3")
         print("<p style='font-family:monospace; font-size:80%'")
         print("<br/>".join(format_tb(kerrr.__traceback__)))
         print("</p>")
 
     except Exception as errr:
-        print("Content-type: text/html")
-        print()  # blank line <=> end of headers
         print("<h3>There was an error:</h3")
         print("<p style='font-family:monospace; font-size:80%'")
         print("<br/>".join(format_tb(errr.__traceback__)))