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Entropy builder finger dragging UI?
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How would one implement an entropy builder with a UI where you drag your finger (like Magic Text.py) until enough x,y coordinates are recorded to build a 256bit hash?
www.bitaddress.com does so with JavaScript but it's over my head.Thanks!
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@SimCityWok
I didn't try this out but maybe here's a start@Webmaster4o is very good with Javascript, maybe he can see exactly how they do it on that website.
import ui import hashlib #Here is a code example from 'http://pythoncentral.io/hashing-strings-with-python/' : hash_object = hashlib.sha256(b'Hello World') hex_dig = hash_object.hexdigest() print hex_dig class TouchHash(ui.View): def __init__(self): self.flex = 'WH' self.name = 'Swipe around to generate a hash' self.complete = False self.hash = '' self.textview = ui.TextView() self.textview.touch_enabled = False self.textview.editable = False self.textview.flex = 'WH' self.add_subview(self.textview) self.present() def do_hash_generation(self, location): #do what is necessary to generate your hash, when complete (100%) do self.complete=True #use the hashlib module???? (included and has documentation on pythonista) #I've never used this. If you want it like that website, my guess is that they string together coordinate information #from the touches and then generate a hash from that. @Webmaster4o may be able to decipher what they are doing. He's pro with JS. self.hash = '' #update it self.textview.text = self.hash #show the text in the textview if self.complete: #print or return the hash self.close() #close the view def touch_began(self, touch): #touch.location provides a 2-tuple (x,y) coordinate. self.do_hash_generation(touch.location) def touch_moved(self, touch): self.do_hash_generation(touch.location) def touch_ended(self, touch): self.do_hash_generation(touch.location) hash = TouchHash() -
Updated with @JonB 's suggestions from below.
import ui import hashlib import clipboard class TouchHash(ui.View): def __init__(self): self.flex = 'WH' self.name = 'Swipe/Touch around to generate a hash' self.hash = hashlib.sha256() self.count = 0 self.textview = ui.TextView() self.textview.touch_enabled = False self.textview.editable = False self.textview.flex = 'WH' self.add_subview(self.textview) self.present() def do_hash_generation(self, location, prev_location, timestamp): if self.count < 100: self.hash.update('{}{}{}{:15f}'.format(location[0],location[1],prev_location,timestamp)) self.count += 1 self.name = str(self.count) + '% complete' self.textview.text = 'Hash: ' + self.hash.hexdigest() #show the text in the textview elif self.count == 100: print self.hash.hexdigest() clipboard.set(self.hash.hexdigest()) self.close() #close the view def touch_began(self, touch): self.do_hash_generation(touch.location, touch.prev_location, touch.timestamp) def touch_moved(self, touch): self.do_hash_generation(touch.location, touch.prev_location, touch.timestamp) def touch_ended(self, touch): #do nothing so that user can touch random spots pass hash = TouchHash() -
I think you want to use .update on your sha256 object each time the touch moves, Then call .digest to get the answer, maybe on touch ended.
Also, I would combine together location, prev_location, and the timestamp i.e something like
update('{}{}{:15f}'.format(t.location,t.prev_location,t.timestamp))
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@ccc said:
https://forum.omz-software.com/topic/2988/dragging-finger-around-screen-to-build-entropy
I'd forgotten I'd asked that.
The answers this time are great though
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Is there a way to have a horizontal bar fill up as the percentage rises?
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Give this a try... Just learned a little bit about doing ui.Path the other day from @Webmaster4o (thanks again btw!). Maybe there's a better way actually accomplish this in code... Not sure!
Now it doesn't automatically close the view at the end. It gives a hud_alert and copies the hash to clipboard.
Because the view is presented without the title bar, you need to swipe down with two fingers to close it.
import ui import hashlib import clipboard import console class TouchHash(ui.View): def __init__(self): self.flex = 'WH' self.hash = hashlib.sha256() self.background_color = 1 self.count = 0 self.hash_label = ui.Label() self.hash_label.font = ('<system>', 8) self.hash_label.alignment = 1 self.hash_label.text_color = 1 self.pr_bar_w = 350 self.add_subview(self.hash_label) self.present(hide_title_bar=True) def do_hash_generation(self, location, prev_location, timestamp): if self.count < 100: self.hash.update('{}{}{}{:15f}'.format(location[0],location[1],prev_location,timestamp)) self.hash_label.text = self.hash.hexdigest() #show the text in the textview self.set_needs_display() elif self.count == 100: clipboard.set(self.hash.hexdigest()) console.hud_alert('Hash on Clipboard') self.count += 1 def touch_began(self, touch): if self.count < 101: self.do_hash_generation(touch.location, touch.prev_location, touch.timestamp) def touch_moved(self, touch): if self.count < 101: self.do_hash_generation(touch.location, touch.prev_location, touch.timestamp) def touch_ended(self, touch): #do nothing so that user can touch random spots pass def draw(self): self.cx, self.cy = self.center self.p_frame = ui.Path.rounded_rect(self.cx-self.pr_bar_w/2,self.cy-35/2,self.pr_bar_w,35, 5) ui.set_color(0.7) self.p_frame.stroke() self.p_bar = ui.Path.rounded_rect(self.cx-self.pr_bar_w/2,self.cy-35/2,self.pr_bar_w*(self.count/100.0),35, 5) ui.set_color('#dd6676') self.p_bar.fill() self.hash_label.frame = (self.cx-self.pr_bar_w/2, self.cy-35/2, self.pr_bar_w, 35) hash = TouchHash() -
One final query....
If I wanted to implement this, how would I change the class code?def make(bits=256): assert bits in (256, 512) hashes = [] for hsh in range(int(bits//256)): myhash = TouchHash() hashes.append(myhash) return "".join(hashes)
