جلسه چهارم پایتون برای هکر های قانونی دوره مقدماتی پاییز ۹۲

در این جلسه به بررسی ساختار های شرطی و حلقه ها در پایتون پرداختیم

Transcript

1. Python for ethical hackers Mohammad reza Kamalifard kamalifard@datasec.ir
2. Python language essentials Module 1: Introduction to Python and Setting up an Environment for Programing Part 4 : Conditional Statements
3. if Statement Like if in other languages but second if called elif if test_condition1: do stuff do stuff elif test_condition2: do stuff do stuff elif test_condition3: do stuff do stuff else: do stuff
4. Python Indentation • Python uses whitespace indentation, rather than curly braces or keywords, to delimit blocks; a feature also termed the off-side rule. • An increase in indentation comes after certain statements; a decrease in indentation signifies the end of the current block.
5. C, C++ #include <iostream> using namespace std; int main(){ cout<<"Hello, World!"; return 0; }
6. C, C++ #include <iostream> using namespace std;int main() {cout<<"Hello,World!";return 0;}
7. Indentation if name == 'ali': print 'Your name is ali' Print ‘Always print this line‘ • 4 space • Tab • Google use 2 space • We use 4 space (PEP 8)
9. $ vim if_statement.py #!/usr/bin/env python name = raw_input('Please Enter Your name! : ') if name == 'reza': print 'You are reza' print 'And a course instructor' elif name == 'Arman': print 'You are Arman' print 'And a student' else: print 'I don\'t know you‘ ~ ~ ~
10. $ chmod a+x if_statement.py $ ./if_statement.py Please Enter Your name! : reza You are reza And a course instructor $ $ ./if_statement.py Please Enter Your name! : ali I don’t know you $ $ ./if_statement.py Please Enter Your name! : Arman You are Arman And a student $
11. While Loops while statement_is_true: do stuff do stuff break : get out if innermost loop continue : start the next pass of the innermost pass : do nothing, placeholder
12. $ vim while_statement.py #!/usr/bin/env python age = int(raw_input('Please Enter Your age ? : ')) while age > 10: print 'You age is grater than 10' ~ ~ ~
13. $ chmod a+x while_statement.py $ ./ while_statement.py Please Enter Your age ? : 23 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10 You age is grater than 10
14. $ vim while_statement.py #!/usr/bin/env python age = 20 while age > 10: age = int(raw_input('Please Enter Your age ? : ')) print 'You age is grater than 10' ~ ~ ~
15. $ chmod a+x while_statement.py $ ./ while_statement.py Please Enter Your age ? : 23 You age is grater than 10 Please Enter Your age ? : 15 You age is grater than 10 Please Enter Your age ? : 18 You age is grater than 10 Please Enter Your age ? : 8 You age is grater than 10 $
16. $ vim while_statement.py #!/usr/bin/env python age = 20 while age > 10: age = int(raw_input('Please Enter Your age ? : ')) if age > 10: print 'Your age is grater than 10' elif age < 10: print 'Your age is smaller than 10' else: print 'Your age is equal to 10' ~ ~
17. $ chmod a+x while_statement.py $ ./ while_statement.py Please Enter Your age ? : 23 You age is grater than 10 Please Enter Your age ? : 15 You age is grater than 10 Please Enter Your age ? : 8 You age is smaller than 10 $ $ ./ while_statement.py Please Enter Your age ? : 17 You age is grater than 10 Please Enter Your age ? : 10 You age is equal to 10 $
18. For Loops for item in object: do stuff do stuff for item in [1, 2, 3] for item in ['a', 2, '3'] for (x,y) in [('reza', 23), ('mohammad', 25)]
19. >>> for item in [1, 2, 3]: ... print item ... 1 2 3
20. item is a name can be anything >>> names = ['Reza', 'Majid', 'Sara', 'Iman'] >>> names ['Reza', 'Majid', 'Sara', 'Iman'] >>> for name in names: ... print name ... Reza Majid Sara Iman >>>
21. >>> info = [('Reza', 23), ('Sara', 20), ('Shayan', 30), ('AmirAli', 21)] >>> info [('Reza', 23), ('Sara', 20), ('Shayan', 30), ('AmirAli', 21)] >>> for (name, age) in info: ... print 'Your name is : %s and Your age is %d' % (name, age) ... Your name is : Reza and Your age is 23 Your name is : Sara and Your age is 20 Your name is : Shayan and Your age is 30 Your name is : AmirAli and Your age is 21 >>>
22. Emulating C style for loops C style loops : for(i=0; i<10; i++) for(i=0; i<10; i++){ cout<<i<<','; } 0,1,2,3,4,5,6,7,8,9,
23. range() range(lower, upper, step) create a list for use range(n) – [0,...,n-1] >>> range(10) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] >>>
24.  References SPSE securitytube training by Vivek Ramachandran SANS Python for Pentesters (SEC573) Violent python Security Power Tools python-course.eu ----------------------------- http://www.tutorialspoint.com/python/python_loops.htm http://www.python-course.eu/blocks.php http://www.python-course.eu/loops.php http://www.python-course.eu/for_loop.php
25. This work is licensed under the Creative Commons Attribution-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nd/3.0/ Copyright 2013 Mohammad Reza Kamalifard All rights reserved. Go to Kamalifard.ir/pysec101 to Download Slides and Course martials .