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Computer Security Exam Professors M. Carminati & S. Zanero Milan, 17/07/2018 Last (family) Name ____________________________ First (given) Name ____________________________ Matricola or Codice Persona ____________________________ Have you done any challenges/homework, even partially? [ ] Yes [ ] No Professor [ ] Carminati [ ] Zanero Instructions ● The exam is composed of 13 pages. Check that you have all of them ● Just as a cross check, tell us whether you have completed the homeworks, by putting an "X" mark appropriately. ● The exam is "closed books". Please put away in a non-suspicious place (i.e. not below the desk) any notebook, or similar. You will be expelled if, at any time, if you do not follow this rule. ● You are not allowed to communicate with other students, and you will be expelled from the exam if you do. ● Shut down and store electronic devices. They will be subject to inspection if found and you may be expelled if you are found using one. ● Please answer within the allowed space. Schemes are good, short answers are recommended. ● You can write in pen or pencil, any color, but ​ avoid writing in red ​ . ● No extra paper is allowed. ● The answers should be written exclusively in the space provided below the questions. READ CAREFULLY ​ ALL THE POINTS ​ OF EACH QUESTION ​ BEFORE ​ WRITING YOUR ​ ANSWER SOLUTION Answer provided in this solution MUST BE CONSIDERED ONLY AS A HINT for the correct answer, and they are not necessarily complete. Page 1 of 13 Computer Security Exam - 17/07/2018 - Professors M. Carminati & S. Zanero Question 1 ( 10 points ) Consider the C program below. 00 ​ #include <stdio.h> 01 #include <stdlib.h> 02 #include <string.h> 03 04 int ​ guess(char *user) { 05 ​ struct ​ { 06 ​ int ​ n; 08 ​ char ​ usr[16]; 09 ​ char ​ buf[16]; 10 } s;…