├── ModernOverflowTargets.pdf ├── BreakingAddressSanitizer.pdf ├── 3.cpp ├── todo ├── adjecent.cpp └── leak.cpp ├── 4.cpp ├── heartbleed.cpp ├── 1.cpp ├── Makefile ├── impossible.cpp ├── todo.cpp ├── integerOverflowDetectionAssmbly.c ├── 2.cpp ├── 6.cpp ├── README.md ├── 5.cpp └── LICENSE /ModernOverflowTargets.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ewimberley/AdvancedMemoryChallenges/HEAD/ModernOverflowTargets.pdf -------------------------------------------------------------------------------- /BreakingAddressSanitizer.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ewimberley/AdvancedMemoryChallenges/HEAD/BreakingAddressSanitizer.pdf -------------------------------------------------------------------------------- /3.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | int a(char* buff2){ 5 | char buff[10]; 6 | scanf("%s", buff); 7 | system(buff2); 8 | } 9 | 10 | int main(){ 11 | char buff2[10] = "dir"; 12 | a(buff2); 13 | } 14 | -------------------------------------------------------------------------------- /todo/adjecent.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | int a(){ 5 | char buff[10]; 6 | char buff2[4] = "dir"; 7 | scanf(buff, "%s"); 8 | system(buff2); 9 | } 10 | 11 | int main(){ 12 | a(); 13 | } 14 | -------------------------------------------------------------------------------- /todo/leak.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | class Test{ 5 | public: 6 | 7 | Test(){ 8 | format[0] = '%'; 9 | format[1] = 's'; 10 | format[2] = '\n'; 11 | format[3] = '\0'; 12 | 13 | buffer2[0] = 'b'; 14 | buffer2[1] = '\0'; 15 | 16 | secret[0] = '1'; 17 | secret[1] = '3'; 18 | secret[2] = '3'; 19 | secret[3] = '7'; 20 | secret[4] = '\0'; 21 | } 22 | 23 | void a(){ 24 | while(true){ 25 | scanf("%s", buffer); 26 | printf(format, buffer2); 27 | } 28 | } 29 | 30 | private: 31 | char buffer[10]; 32 | char format[10]; 33 | char buffer2[10]; 34 | char secret[10]; 35 | }; 36 | 37 | int main(){ 38 | Test aTest = Test(); 39 | aTest.a(); 40 | } 41 | -------------------------------------------------------------------------------- /4.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | int a(){ 5 | int position = 0; 6 | char in; 7 | char buff2[10] = "dir"; 8 | char buff[10]; 9 | printf("buff position: %p\n", buff); 10 | printf("buff2 position: %p\n", buff2); 11 | scanf("%d\n", &position); 12 | if(position < 0){ 13 | printf("nice try...\n"); 14 | exit(1); 15 | } 16 | position = position*2; 17 | in = 0; 18 | while(position < 10 && in != '\n'){ 19 | scanf("%c", &in); 20 | buff[position] = in; 21 | printf("%d\n", position); 22 | position++; 23 | } 24 | //scanf("%s", buff); 25 | printf("buff: %s\n", buff); 26 | printf("buff2: %s\n", buff2); 27 | system(buff2); 28 | } 29 | 30 | int main(){ 31 | a(); 32 | } 33 | -------------------------------------------------------------------------------- /heartbleed.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | #include 4 | 5 | int main(){ 6 | int messageLength = 0; 7 | char in; 8 | char message[10]; 9 | char secret[10] = "isASecret"; 10 | char response[30]; 11 | printf("Type a message length:"); 12 | scanf("%d", &messageLength); 13 | printf("Type a message:"); 14 | scanf("\n"); 15 | int i; 16 | for(i = 0; i < messageLength && i < 10; i++){ 17 | scanf("%c", &in); 18 | message[i] = in; 19 | } 20 | 21 | //memcpy(&response, &message, messageLength); 22 | for(int i = 0; i < messageLength && i < 30; i++){ 23 | response[i] = message[i]; 24 | } 25 | 26 | //printf("Your message was:"); 27 | //printf("%10c\n", message); 28 | printf("Your response is:"); 29 | for(int i = 0; i < messageLength && i < 30; i++){ 30 | printf("%c", response[i]); 31 | } 32 | printf("\n"); 33 | } 34 | -------------------------------------------------------------------------------- /1.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | /** 5 | * An object that contains two character arrays, one determined by the user, and one that contains a shell command. 6 | */ 7 | class Test{ 8 | public: 9 | 10 | /** 11 | * Set the command buffer to the command "ls". 12 | */ 13 | Test(){ 14 | command[0] = 'l'; 15 | command[1] = 's'; 16 | command[2] = '\0'; 17 | } 18 | 19 | /** 20 | * Read a string from standard input, then execute the command in the command character array. 21 | */ 22 | void a(){ 23 | scanf("%s", buffer); //read from standard input until null byte 24 | system(command); //execute the command in the command character array 25 | } 26 | 27 | private: 28 | char buffer[10]; //stores a 10 character string 29 | char command[10]; //stores a 10 character command passed to the 30 | }; 31 | 32 | int main(){ 33 | //this object is stored on the stack 34 | Test aTest = Test(); 35 | aTest.a(); 36 | } 37 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | all: 2 | g++ -I./ -g -o 1.bin -fstack-protector-all 1.cpp 3 | g++ -I./ -g -o 2.bin -fstack-protector-all 2.cpp 4 | g++ -I./ -g -o 3.bin -fstack-protector-all 3.cpp 5 | 6 | #Note: this only works on systems that have g++ 4.8 or higher as default 7 | g++ -I./ -g -o 4.bin -fsanitize=address 4.cpp 8 | g++ -I./ -g -o impossible.bin -ftrapv -fsanitize=address impossible.cpp 9 | g++ -I./ -g -o 5.bin -fstack-protector-all 5.cpp 10 | g++ -I./ -g -o 6.bin -fsanitize=address 6.cpp 11 | g++ -I./ -g -o todo.bin -fsanitize=address todo.cpp 12 | 13 | #If you don't have g++ 4.8 or higher as default, use this instead: 14 | #g++-4.8 -I./ -g -o 4.bin -fsanitize=address 4.cpp 15 | #g++-4.8 -I./ -g -o impossible.bin -ftrapv -fsanitize=address impossible.cpp 16 | #g++-4.8 -I./ -g -o 5.bin -fstack-protector-all 5.cpp 17 | #g++-4.8 -I./ -g -o 6.bin -fsanitize=address 6.cpp 18 | #g++-4.8 -I./ -g -o todo.bin -fsanitize=address todo.cpp 19 | clean: 20 | rm -f *.bin *.o *.so *_expanded.cpp 21 | -------------------------------------------------------------------------------- /impossible.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | #include 4 | 5 | void handler(int sig) 6 | { 7 | printf("nice try, must be less than 10...\n"); 8 | } 9 | 10 | int a(){ 11 | long position = 0; 12 | char in; 13 | char buff2[10] = "dir"; 14 | char buff[10]; 15 | printf("buff position: %p\n", buff); 16 | printf("buff2 position: %p\n", buff2); 17 | scanf("%ld", &position); 18 | printf("position: %ld\n", position); 19 | if(position < 0){ 20 | printf("nice try, must be more than 0...\n"); 21 | exit(1); 22 | } 23 | position = position*2; 24 | printf("position*2: %ld\n", position); 25 | in = 0; 26 | while(position < 10 && in != '\n'){ 27 | scanf("%c", &in); 28 | buff[position] = in; 29 | printf("%d\n", position); 30 | position++; 31 | } 32 | //scanf("%s", buff); 33 | printf("buff: %s\n", buff); 34 | printf("buff2: %s\n", buff2); 35 | system(buff2); 36 | } 37 | 38 | int main(){ 39 | signal(SIGABRT, &handler); 40 | a(); 41 | return 0; 42 | } 43 | -------------------------------------------------------------------------------- /todo.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | /** 5 | * A class that contains a character array, provides a method for reading standard input into it. 6 | */ 7 | class Test{ 8 | public: 9 | 10 | Test(){ 11 | } 12 | 13 | /** 14 | * Scan a string into the character array. 15 | */ 16 | void a(){ 17 | printf("Input position:"); 18 | scanf("%d", &position); 19 | if(position > 9) 20 | position = 9; 21 | if(position < 0) 22 | position = 0; 23 | printf("Input a string:"); 24 | scanf("%s", &buffer); 25 | printf("You entered string: %s\n", buffer); 26 | } 27 | 28 | char buffer[10]; 29 | int position; 30 | }; 31 | 32 | int a(){ 33 | int things[10]; 34 | printf("things addr:%p\n", &things); 35 | for(int i = 0; i < 10; i++){ 36 | things[i] = i; 37 | } 38 | int input = -1; 39 | while(input != 0){ 40 | Test* aTest = new Test(); 41 | aTest->a(); 42 | printf("Input value:"); 43 | scanf("%d", &input); 44 | printf("Setting index %d (%p) to %d\n", aTest->position, things + aTest->position, input); 45 | things[aTest->position] = input; 46 | } 47 | } 48 | 49 | int main(){ 50 | a(); 51 | } 52 | -------------------------------------------------------------------------------- /integerOverflowDetectionAssmbly.c: -------------------------------------------------------------------------------- 1 | #include "stdafx.h" 2 | #include "stdio.h" 3 | #include "stdlib.h" 4 | 5 | /* 6 | * Note: this version may only work in Visual Studio. 7 | * It would be nice to get it working in gcc, but jno didn't seem to have an effect. 8 | * Maybe an instruction ordering problem? Does something reset the overflow bit in the flag register? 9 | */ 10 | 11 | int a(){ 12 | int position = 0; 13 | char in; 14 | char vuln[10] = "dir"; 15 | char buff[10] = "dir"; 16 | 17 | printf("vuln position: %p\n", buff); 18 | printf("buff position: %p\n", vuln); 19 | 20 | scanf_s("%d\n", &position); 21 | if (position < 0){ 22 | printf("nice try...\n"); 23 | exit(1); 24 | } 25 | 26 | position = position * 2; 27 | __asm 28 | { 29 | jno NO_OVERFLOW; 30 | jmp abort 31 | NO_OVERFLOW : 32 | } 33 | 34 | in = 0; 35 | while (position < 9){ 36 | printf("%p\n", &vuln[position]); 37 | vuln[position] = getchar(); 38 | position++; 39 | } 40 | 41 | printf("vuln: %s\n", buff); 42 | printf("buff: %s\n", vuln); 43 | 44 | system(buff); 45 | return 0; 46 | } 47 | 48 | int _tmain(int argc, _TCHAR* argv[]){ 49 | a(); 50 | return 0; 51 | } 52 | -------------------------------------------------------------------------------- /2.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | /** 5 | * A class that contains a character array, provides a method for reading standard input into it. 6 | */ 7 | class Test{ 8 | public: 9 | 10 | /** 11 | * Scan a string into the character array. 12 | */ 13 | void a(){ 14 | scanf("%s", buffer); 15 | } 16 | 17 | private: 18 | char buffer[10]; 19 | }; 20 | 21 | /** 22 | * A class that provides a method to execute a command. 23 | */ 24 | class Command{ 25 | public: 26 | 27 | Command(){ 28 | command[0] = 'l'; 29 | command[1] = 's'; 30 | command[2] = '\0'; 31 | } 32 | 33 | /** 34 | * Execute the command in the character array. 35 | */ 36 | void a(){ 37 | system(command); 38 | } 39 | 40 | private: 41 | char command[10]; 42 | }; 43 | 44 | int main(){ 45 | //put some objects in the heap 46 | Test* aTest = new Test(); 47 | Command* c1 = new Command(); 48 | Command* c2 = new Command(); 49 | Command* c3 = new Command(); 50 | Command* c4 = new Command(); 51 | //read from the standard input 52 | aTest->a(); 53 | //execute some commands 54 | c2->a(); 55 | delete c2; 56 | c3->a(); 57 | delete c3; 58 | c4->a(); 59 | delete c4; 60 | delete aTest; 61 | delete c1; 62 | } 63 | -------------------------------------------------------------------------------- /6.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | 4 | /** 5 | * A class that contains a character array, provides a method for reading standard input into it. 6 | */ 7 | class Test{ 8 | public: 9 | 10 | Test(){ 11 | } 12 | 13 | /** 14 | * Scan a string into the character array. 15 | */ 16 | void a(){ 17 | printf("Input position:"); 18 | scanf("%d", &position); 19 | if(position > 9) 20 | position = 9; 21 | if(position < 0) 22 | position = 0; 23 | printf("Input a string:"); 24 | scanf("%s", &buffer); 25 | printf("You entered string: %s\n", buffer); 26 | } 27 | 28 | char buffer[10]; 29 | int position; 30 | }; 31 | 32 | int a(){ 33 | int things[10]; 34 | printf("things addr:%p\n", &things); 35 | for(int i = 0; i < 10; i++){ 36 | things[i] = i; 37 | } 38 | int input = -1; 39 | while(input != 0){ 40 | Test* aTest = new Test(); 41 | aTest->a(); 42 | printf("Input value:"); 43 | scanf("%d", &input); 44 | printf("Setting index %d (%p) to %d\n", aTest->position, things + aTest->position, input); 45 | things[aTest->position] = input; 46 | } 47 | } 48 | 49 | int main(){ 50 | char command[10] = "ls"; 51 | printf("command addr:%p\n", &command); 52 | a(); 53 | system(command); 54 | } 55 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | AdvancedMemoryChallenges 2 | ======================== 3 | 4 | Advanced buffer overflow and memory corruption challenges. 5 | 6 | INSTRUCTIONS: 7 | 8 | 1. Install gcc 4.8 or above (I recommend a late version of Ubuntu. I haven't really tested these on CentOS, but they should work. All other systems and all bets are off.) 9 | 2. Run the command "make" in the main project directory 10 | 3. Try to get each program to pop a shell (or change the control flow to your advantage in some way) 11 | without modifying the source code. You can try to execute some shell code, but that's the old boring 12 | way to do things. Look for something else. 13 | 4. Profit? 14 | 15 | For some spoilers read: 16 | 17 | http://packetstormsecurity.com/files/121751/Modern-Overflow-Targets.html 18 | 19 | or 20 | 21 | http://packetstormsecurity.com/files/123977/Bypassing-AddressSanitizer.html 22 | 23 | ---------------------------------------------------------------------------------- 24 | Spoilers below! 25 | ---------------------------------------------------------------------------------- 26 | ---------------------------------------------------------------------------------- 27 | ---------------------------------------------------------------------------------- 28 | ---------------------------------------------------------------------------------- 29 | ---------------------------------------------------------------------------------- 30 | ---------------------------------------------------------------------------------- 31 | ---------------------------------------------------------------------------------- 32 | 33 | Hints and Challenge Description 34 | 35 | 36 | 1. Stack Objects - Did you know you could put objects on the stack? -fstack-protector-all prevents you from writing over the stored instruction pointer, but that doesn't mean it prevents *all* buffer overflows on the stack. Just don't write over the canary... 37 | 38 | 2. Heap Objects - Overflowing is a little bit different on the heap. Metadata checks will test the linked list pointers used to maintain allocations. If you free/delete after a heap overflow on modern clib you're likely to get a segfault. 39 | 40 | 3. Canary Conundrums - Oh no! The target is on the other side of a canary from the vulnerable buffer! When function a returns there's bound to be a segfault. If function a returns... 41 | 42 | 4. Integer Behavior - Hmm, it looks like there's some careful sanitization on that integer input. How does that ALU thing work again? Plus, this was compiled with AddressSanitizer. One wrong byte and it'll be a segfault. 43 | 44 | 5. Heap Havoc - In the real world the heap is constantly changing. Challenge number 2 is pretty trivial compared to this one. 45 | 46 | 6. AddressSanitizer Woes - AddressSanitizer is extremely carefully thought out. It was very challenging to balance improved security without breaking backwards compatibility. Sometimes, all it takes is a few corrupted bytes to pop a shell. That's good, because AddressSanitizer doesn't give you all that many bytes to work with. 47 | 48 | More to come later... 49 | -------------------------------------------------------------------------------- /5.cpp: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | #include 4 | 5 | //Logic flows like water, 6 | //powerful and swift. 7 | //If you are not careful 8 | //friend you just might find: 9 | //logic turns against you, 10 | //seeping through a rift. 11 | 12 | //To complete this challenge, be like water and find the cracks. 13 | //Note: if you are trying this on a system that doesn't have heap metadata protection, it won't be much fun. 14 | 15 | /** 16 | * A class that contains a character array, provides a method for reading standard input into it. 17 | */ 18 | class Test{ 19 | public: 20 | 21 | Test(){ 22 | printf("Making a new test...\n"); 23 | } 24 | 25 | /** 26 | * Scan a string into the character array. 27 | */ 28 | void a(){ 29 | printf("Reading string...\n"); 30 | scanf("%s", buffer); 31 | } 32 | 33 | private: 34 | char buffer[10]; 35 | }; 36 | 37 | /** 38 | * A class that provides a method to execute a command. 39 | */ 40 | class Command{ 41 | public: 42 | 43 | Command(){ 44 | printf("Making a new command...\n"); 45 | command[0] = 'l'; 46 | command[1] = 's'; 47 | command[2] = '\0'; 48 | } 49 | 50 | /** 51 | * Execute the command in the character array. 52 | */ 53 | void a(){ 54 | printf("Running shell command %s\n", command); 55 | system(command); 56 | } 57 | 58 | private: 59 | char command[10]; 60 | }; 61 | 62 | class Fluff{ 63 | char fluff[128]; 64 | }; 65 | 66 | int main(){ 67 | 68 | char action[32]; 69 | Test* tests[10]; 70 | int onTest = 0; 71 | int setTest = 0; 72 | Command* commands[10]; 73 | int onCommand = 0; 74 | int runCommand = 0; 75 | Fluff* someFluff[5]; 76 | int onFluff = 0; 77 | 78 | do { 79 | scanf("%31s", action); 80 | printf("running action %s\n", action); 81 | //make a new test 82 | if(strcmp("newtest", action) == 0){ 83 | if(onTest < 10){ 84 | tests[onTest] = new Test(); 85 | onTest++; 86 | } 87 | } 88 | //make a new command, also add some fluff 89 | else if(strcmp("newcommand", action) == 0){ 90 | if(onFluff < 5){ 91 | someFluff[onFluff] = new Fluff(); 92 | onFluff++; 93 | } 94 | if(onCommand < 10){ 95 | commands[onCommand] = new Command(); 96 | onCommand++; 97 | } 98 | } 99 | //set the value of any test, get rid of some fluff 100 | else if(strcmp("settest", action) == 0){ 101 | printf("Number of tests:%d Set test number:", onTest); 102 | scanf("%d", &setTest); 103 | if(setTest >= 0 && setTest < onTest){ 104 | tests[setTest]->a(); 105 | } 106 | if(onFluff < 5 && someFluff[onFluff] != NULL){ 107 | delete someFluff[onFluff]; 108 | } 109 | } 110 | //run any command 111 | else if(strcmp("runcommand", action) == 0){ 112 | printf("Number of commands:%d Run command number:", onCommand); 113 | scanf("%d", &runCommand); 114 | if(runCommand >= 0 && runCommand < onCommand){ 115 | commands[runCommand]->a(); 116 | } 117 | } 118 | 119 | } while(strcmp("quit",action) != 0); 120 | 121 | //cleanup 122 | for(int i = 0; i < 10; i++){ 123 | delete commands[i]; 124 | } 125 | for(int i = 0; i < 10; i++){ 126 | delete tests[i]; 127 | } 128 | } 129 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 2, June 1991 3 | 4 | Copyright (C) 1989, 1991 Free Software Foundation, Inc., 5 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 6 | Everyone is permitted to copy and distribute verbatim copies 7 | of this license document, but changing it is not allowed. 8 | 9 | Preamble 10 | 11 | The licenses for most software are designed to take away your 12 | freedom to share and change it. By contrast, the GNU General Public 13 | License is intended to guarantee your freedom to share and change free 14 | software--to make sure the software is free for all its users. This 15 | General Public License applies to most of the Free Software 16 | Foundation's software and to any other program whose authors commit to 17 | using it. (Some other Free Software Foundation software is covered by 18 | the GNU Lesser General Public License instead.) You can apply it to 19 | your programs, too. 20 | 21 | When we speak of free software, we are referring to freedom, not 22 | price. Our General Public Licenses are designed to make sure that you 23 | have the freedom to distribute copies of free software (and charge for 24 | this service if you wish), that you receive source code or can get it 25 | if you want it, that you can change the software or use pieces of it 26 | in new free programs; and that you know you can do these things. 27 | 28 | To protect your rights, we need to make restrictions that forbid 29 | anyone to deny you these rights or to ask you to surrender the rights. 30 | These restrictions translate to certain responsibilities for you if you 31 | distribute copies of the software, or if you modify it. 32 | 33 | For example, if you distribute copies of such a program, whether 34 | gratis or for a fee, you must give the recipients all the rights that 35 | you have. You must make sure that they, too, receive or can get the 36 | source code. And you must show them these terms so they know their 37 | rights. 38 | 39 | We protect your rights with two steps: (1) copyright the software, and 40 | (2) offer you this license which gives you legal permission to copy, 41 | distribute and/or modify the software. 42 | 43 | Also, for each author's protection and ours, we want to make certain 44 | that everyone understands that there is no warranty for this free 45 | software. If the software is modified by someone else and passed on, we 46 | want its recipients to know that what they have is not the original, so 47 | that any problems introduced by others will not reflect on the original 48 | authors' reputations. 49 | 50 | Finally, any free program is threatened constantly by software 51 | patents. We wish to avoid the danger that redistributors of a free 52 | program will individually obtain patent licenses, in effect making the 53 | program proprietary. To prevent this, we have made it clear that any 54 | patent must be licensed for everyone's free use or not licensed at all. 55 | 56 | The precise terms and conditions for copying, distribution and 57 | modification follow. 58 | 59 | GNU GENERAL PUBLIC LICENSE 60 | TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 61 | 62 | 0. This License applies to any program or other work which contains 63 | a notice placed by the copyright holder saying it may be distributed 64 | under the terms of this General Public License. The "Program", below, 65 | refers to any such program or work, and a "work based on the Program" 66 | means either the Program or any derivative work under copyright law: 67 | that is to say, a work containing the Program or a portion of it, 68 | either verbatim or with modifications and/or translated into another 69 | language. (Hereinafter, translation is included without limitation in 70 | the term "modification".) Each licensee is addressed as "you". 71 | 72 | Activities other than copying, distribution and modification are not 73 | covered by this License; they are outside its scope. The act of 74 | running the Program is not restricted, and the output from the Program 75 | is covered only if its contents constitute a work based on the 76 | Program (independent of having been made by running the Program). 77 | Whether that is true depends on what the Program does. 78 | 79 | 1. You may copy and distribute verbatim copies of the Program's 80 | source code as you receive it, in any medium, provided that you 81 | conspicuously and appropriately publish on each copy an appropriate 82 | copyright notice and disclaimer of warranty; keep intact all the 83 | notices that refer to this License and to the absence of any warranty; 84 | and give any other recipients of the Program a copy of this License 85 | along with the Program. 86 | 87 | You may charge a fee for the physical act of transferring a copy, and 88 | you may at your option offer warranty protection in exchange for a fee. 89 | 90 | 2. You may modify your copy or copies of the Program or any portion 91 | of it, thus forming a work based on the Program, and copy and 92 | distribute such modifications or work under the terms of Section 1 93 | above, provided that you also meet all of these conditions: 94 | 95 | a) You must cause the modified files to carry prominent notices 96 | stating that you changed the files and the date of any change. 97 | 98 | b) You must cause any work that you distribute or publish, that in 99 | whole or in part contains or is derived from the Program or any 100 | part thereof, to be licensed as a whole at no charge to all third 101 | parties under the terms of this License. 102 | 103 | c) If the modified program normally reads commands interactively 104 | when run, you must cause it, when started running for such 105 | interactive use in the most ordinary way, to print or display an 106 | announcement including an appropriate copyright notice and a 107 | notice that there is no warranty (or else, saying that you provide 108 | a warranty) and that users may redistribute the program under 109 | these conditions, and telling the user how to view a copy of this 110 | License. (Exception: if the Program itself is interactive but 111 | does not normally print such an announcement, your work based on 112 | the Program is not required to print an announcement.) 113 | 114 | These requirements apply to the modified work as a whole. If 115 | identifiable sections of that work are not derived from the Program, 116 | and can be reasonably considered independent and separate works in 117 | themselves, then this License, and its terms, do not apply to those 118 | sections when you distribute them as separate works. But when you 119 | distribute the same sections as part of a whole which is a work based 120 | on the Program, the distribution of the whole must be on the terms of 121 | this License, whose permissions for other licensees extend to the 122 | entire whole, and thus to each and every part regardless of who wrote it. 123 | 124 | Thus, it is not the intent of this section to claim rights or contest 125 | your rights to work written entirely by you; rather, the intent is to 126 | exercise the right to control the distribution of derivative or 127 | collective works based on the Program. 128 | 129 | In addition, mere aggregation of another work not based on the Program 130 | with the Program (or with a work based on the Program) on a volume of 131 | a storage or distribution medium does not bring the other work under 132 | the scope of this License. 133 | 134 | 3. You may copy and distribute the Program (or a work based on it, 135 | under Section 2) in object code or executable form under the terms of 136 | Sections 1 and 2 above provided that you also do one of the following: 137 | 138 | a) Accompany it with the complete corresponding machine-readable 139 | source code, which must be distributed under the terms of Sections 140 | 1 and 2 above on a medium customarily used for software interchange; or, 141 | 142 | b) Accompany it with a written offer, valid for at least three 143 | years, to give any third party, for a charge no more than your 144 | cost of physically performing source distribution, a complete 145 | machine-readable copy of the corresponding source code, to be 146 | distributed under the terms of Sections 1 and 2 above on a medium 147 | customarily used for software interchange; or, 148 | 149 | c) Accompany it with the information you received as to the offer 150 | to distribute corresponding source code. (This alternative is 151 | allowed only for noncommercial distribution and only if you 152 | received the program in object code or executable form with such 153 | an offer, in accord with Subsection b above.) 154 | 155 | The source code for a work means the preferred form of the work for 156 | making modifications to it. For an executable work, complete source 157 | code means all the source code for all modules it contains, plus any 158 | associated interface definition files, plus the scripts used to 159 | control compilation and installation of the executable. However, as a 160 | special exception, the source code distributed need not include 161 | anything that is normally distributed (in either source or binary 162 | form) with the major components (compiler, kernel, and so on) of the 163 | operating system on which the executable runs, unless that component 164 | itself accompanies the executable. 165 | 166 | If distribution of executable or object code is made by offering 167 | access to copy from a designated place, then offering equivalent 168 | access to copy the source code from the same place counts as 169 | distribution of the source code, even though third parties are not 170 | compelled to copy the source along with the object code. 171 | 172 | 4. You may not copy, modify, sublicense, or distribute the Program 173 | except as expressly provided under this License. Any attempt 174 | otherwise to copy, modify, sublicense or distribute the Program is 175 | void, and will automatically terminate your rights under this License. 176 | However, parties who have received copies, or rights, from you under 177 | this License will not have their licenses terminated so long as such 178 | parties remain in full compliance. 179 | 180 | 5. You are not required to accept this License, since you have not 181 | signed it. However, nothing else grants you permission to modify or 182 | distribute the Program or its derivative works. These actions are 183 | prohibited by law if you do not accept this License. Therefore, by 184 | modifying or distributing the Program (or any work based on the 185 | Program), you indicate your acceptance of this License to do so, and 186 | all its terms and conditions for copying, distributing or modifying 187 | the Program or works based on it. 188 | 189 | 6. Each time you redistribute the Program (or any work based on the 190 | Program), the recipient automatically receives a license from the 191 | original licensor to copy, distribute or modify the Program subject to 192 | these terms and conditions. You may not impose any further 193 | restrictions on the recipients' exercise of the rights granted herein. 194 | You are not responsible for enforcing compliance by third parties to 195 | this License. 196 | 197 | 7. If, as a consequence of a court judgment or allegation of patent 198 | infringement or for any other reason (not limited to patent issues), 199 | conditions are imposed on you (whether by court order, agreement or 200 | otherwise) that contradict the conditions of this License, they do not 201 | excuse you from the conditions of this License. If you cannot 202 | distribute so as to satisfy simultaneously your obligations under this 203 | License and any other pertinent obligations, then as a consequence you 204 | may not distribute the Program at all. For example, if a patent 205 | license would not permit royalty-free redistribution of the Program by 206 | all those who receive copies directly or indirectly through you, then 207 | the only way you could satisfy both it and this License would be to 208 | refrain entirely from distribution of the Program. 209 | 210 | If any portion of this section is held invalid or unenforceable under 211 | any particular circumstance, the balance of the section is intended to 212 | apply and the section as a whole is intended to apply in other 213 | circumstances. 214 | 215 | It is not the purpose of this section to induce you to infringe any 216 | patents or other property right claims or to contest validity of any 217 | such claims; this section has the sole purpose of protecting the 218 | integrity of the free software distribution system, which is 219 | implemented by public license practices. Many people have made 220 | generous contributions to the wide range of software distributed 221 | through that system in reliance on consistent application of that 222 | system; it is up to the author/donor to decide if he or she is willing 223 | to distribute software through any other system and a licensee cannot 224 | impose that choice. 225 | 226 | This section is intended to make thoroughly clear what is believed to 227 | be a consequence of the rest of this License. 228 | 229 | 8. If the distribution and/or use of the Program is restricted in 230 | certain countries either by patents or by copyrighted interfaces, the 231 | original copyright holder who places the Program under this License 232 | may add an explicit geographical distribution limitation excluding 233 | those countries, so that distribution is permitted only in or among 234 | countries not thus excluded. In such case, this License incorporates 235 | the limitation as if written in the body of this License. 236 | 237 | 9. The Free Software Foundation may publish revised and/or new versions 238 | of the General Public License from time to time. Such new versions will 239 | be similar in spirit to the present version, but may differ in detail to 240 | address new problems or concerns. 241 | 242 | Each version is given a distinguishing version number. If the Program 243 | specifies a version number of this License which applies to it and "any 244 | later version", you have the option of following the terms and conditions 245 | either of that version or of any later version published by the Free 246 | Software Foundation. If the Program does not specify a version number of 247 | this License, you may choose any version ever published by the Free Software 248 | Foundation. 249 | 250 | 10. If you wish to incorporate parts of the Program into other free 251 | programs whose distribution conditions are different, write to the author 252 | to ask for permission. For software which is copyrighted by the Free 253 | Software Foundation, write to the Free Software Foundation; we sometimes 254 | make exceptions for this. Our decision will be guided by the two goals 255 | of preserving the free status of all derivatives of our free software and 256 | of promoting the sharing and reuse of software generally. 257 | 258 | NO WARRANTY 259 | 260 | 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 261 | FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 262 | OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 263 | PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 264 | OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 265 | MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 266 | TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 267 | PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 268 | REPAIR OR CORRECTION. 269 | 270 | 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 271 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 272 | REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 273 | INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 274 | OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 275 | TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 276 | YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 277 | PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 278 | POSSIBILITY OF SUCH DAMAGES. 279 | 280 | END OF TERMS AND CONDITIONS 281 | 282 | How to Apply These Terms to Your New Programs 283 | 284 | If you develop a new program, and you want it to be of the greatest 285 | possible use to the public, the best way to achieve this is to make it 286 | free software which everyone can redistribute and change under these terms. 287 | 288 | To do so, attach the following notices to the program. It is safest 289 | to attach them to the start of each source file to most effectively 290 | convey the exclusion of warranty; and each file should have at least 291 | the "copyright" line and a pointer to where the full notice is found. 292 | 293 | Advanced buffer overflow and memory corruption challenges 294 | Copyright (C) 2013 Eric Wimberley 295 | 296 | This program is free software; you can redistribute it and/or modify 297 | it under the terms of the GNU General Public License as published by 298 | the Free Software Foundation; either version 2 of the License, or 299 | (at your option) any later version. 300 | 301 | This program is distributed in the hope that it will be useful, 302 | but WITHOUT ANY WARRANTY; without even the implied warranty of 303 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 304 | GNU General Public License for more details. 305 | 306 | You should have received a copy of the GNU General Public License along 307 | with this program; if not, write to the Free Software Foundation, Inc., 308 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 309 | 310 | Also add information on how to contact you by electronic and paper mail. 311 | 312 | If the program is interactive, make it output a short notice like this 313 | when it starts in an interactive mode: 314 | 315 | Gnomovision version 69, Copyright (C) year name of author 316 | Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 317 | This is free software, and you are welcome to redistribute it 318 | under certain conditions; type `show c' for details. 319 | 320 | The hypothetical commands `show w' and `show c' should show the appropriate 321 | parts of the General Public License. Of course, the commands you use may 322 | be called something other than `show w' and `show c'; they could even be 323 | mouse-clicks or menu items--whatever suits your program. 324 | 325 | You should also get your employer (if you work as a programmer) or your 326 | school, if any, to sign a "copyright disclaimer" for the program, if 327 | necessary. Here is a sample; alter the names: 328 | 329 | Yoyodyne, Inc., hereby disclaims all copyright interest in the program 330 | `Gnomovision' (which makes passes at compilers) written by James Hacker. 331 | 332 | {signature of Ty Coon}, 1 April 1989 333 | Ty Coon, President of Vice 334 | 335 | This General Public License does not permit incorporating your program into 336 | proprietary programs. If your program is a subroutine library, you may 337 | consider it more useful to permit linking proprietary applications with the 338 | library. If this is what you want to do, use the GNU Lesser General 339 | Public License instead of this License. 340 | --------------------------------------------------------------------------------