{"id":572,"date":"2013-11-05T23:31:46","date_gmt":"2013-11-05T23:31:46","guid":{"rendered":"http:\/\/www.gironsec.com\/blog\/?p=572"},"modified":"2013-11-05T23:31:46","modified_gmt":"2013-11-05T23:31:46","slug":"i","status":"publish","type":"post","link":"https:\/\/www.gironsec.com\/blog\/2013\/11\/i\/","title":{"rendered":"I <3 C"},"content":{"rendered":"

I love C. It was my first language I learned. Any other security professional will tell you, C is the bomb, but on the same token, a source for a lot of head ache.<\/p>\n

To anyone out there aspiring to be a security professional, get to know C and assembly. C lets you inline assembly which makes it awesome. The key is to practice your programming and practice often. Its too easy to forget. <\/p>\n

<\/p>\n

\n
#include <windows.h><\/span>\r\n#include <stdio.h><\/span>\r\nchar<\/span> *<\/span>ppt<\/span>(char<\/span> *<\/span>);\r\nlong<\/span> GetFS<\/span>(FILE<\/span> *<\/span>);\r\nint<\/span> main<\/span>(int<\/span> argc, char<\/span> *<\/span>argv[])\r\n{\r\n\tif<\/span>(argc <<\/span> 3<\/span>)\r\n\t{\r\n\tprintf("Usage is %s filename xorcount"<\/span>,argv[0<\/span>]); \r\n\treturn<\/span> 0<\/span>;\r\n\t}\r\n\tconst<\/span> int<\/span> xorcount =<\/span> atoi(argv[2<\/span>]);\r\n\tchar<\/span> *<\/span>derp =<\/span> ppt(argv[1<\/span>]);\r\n\tFILE<\/span>  *<\/span>pFile =<\/span> fopen ( argv[1<\/span>] , "rb"<\/span> );\r\n\tunsigned<\/span> int<\/span> fsg =<\/span> GetFS(pFile);\r\n\tfclose(pFile);\r\n\tint<\/span> x;\r\n\tfor<\/span>(x=<\/span>0<\/span>;x<<\/span>fsg;x++<\/span>)\r\n\t{\r\n\t\tint<\/span> vg =<\/span> derp[x];\r\n\t\t\r\n\t\t__asm<\/span>\r\n\t\t{\r\n\t\t\tmov eax,xorcount\r\n\t\t\txor vg,eax\r\n\t\t}\r\n\t\tprintf("Hex pos: %d <\/span>\\t<\/span>Hex Value: %2X<\/span>\\t<\/span>Ascii Char Value: %c<\/span>\\t<\/span>Xor'd value of char: %d<\/span>\\r\\n<\/span>"<\/span>,x,derp[x],derp[x],vg);\r\n\t\tvg=<\/span>0<\/span>;\r\n\t}\r\n\t__asm<\/span>\r\n\t{\r\n\tsar fsg,3<\/span>\r\n\t}\r\n\tprintf("File size shifted right 3: %i <\/span>\\r\\n<\/span>"<\/span>,fsg);\r\n\t__asm<\/span>\r\n\t{\r\n\tsal fsg,3<\/span>\r\n\tmov eax,1024<\/span>\r\n\tcrc32 eax,fsg\r\n\t}\r\n\tprintf("File size shifted left 3: %i <\/span>\\r\\n<\/span>"<\/span>,fsg);\r\n}\r\nchar<\/span>*<\/span> ppt<\/span>(char<\/span> *<\/span>filename) \/\/ load file into buffer and return<\/span>\r\n{\r\n  FILE<\/span> *<\/span> pFile;\r\n  long<\/span> lSize;\r\n  char<\/span> *<\/span> buffer;\r\n  size_t<\/span> result;\r\n  pFile =<\/span> fopen ( filename , "rb"<\/span> );\r\n  if<\/span> (pFile==<\/span>NULL<\/span>) {fputs ("File error"<\/span>,stderr); exit (1<\/span>);}\r\n  fseek (pFile , 0<\/span> , SEEK_END);\r\n  lSize =<\/span> ftell (pFile);\r\n  rewind (pFile);\r\n  buffer =<\/span> (char<\/span>*<\/span>) malloc (sizeof<\/span>(char<\/span>)*<\/span>lSize);\r\n  if<\/span> (buffer ==<\/span> NULL<\/span>) {fputs ("Memory error"<\/span>,stderr); exit (2<\/span>);}\r\n  result =<\/span> fread (buffer,1<\/span>,lSize,pFile);\r\n  if<\/span> (result !=<\/span> lSize) {fputs ("Reading error"<\/span>,stderr); exit (3<\/span>);}\r\n  fclose (pFile);\r\n  return<\/span> buffer;\r\n}\r\nlong<\/span> GetFS<\/span>(FILE<\/span> *<\/span>lol) \/\/ get file size<\/span>\r\n{\r\n  long<\/span> lSize =<\/span> 0<\/span>;\r\n  fseek (lol , 0<\/span> , SEEK_END);\r\n  lSize =<\/span> ftell (lol);\r\n  rewind (lol);\r\n  return<\/span> lSize;\r\n}\r\n<\/pre>\n<\/div>\n
This is kind of a filler post. I just feel like updating the blog with something. On that note, I’m split on what i want to do next. Was thinking of making a segway into hardware hacking for a little while as I had a project in mind, but we shall see. \"iwHX6\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
I love C. It was my first language I learned. Any other security professional will tell you, C is the bomb, but on the same token, a source for a lot of head ache. To anyone out there aspiring to be a security professional, get to know C and assembly. C lets you inline assembly […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/posts\/572"}],"collection":[{"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/comments?post=572"}],"version-history":[{"count":1,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/posts\/572\/revisions"}],"predecessor-version":[{"id":574,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/posts\/572\/revisions\/574"}],"wp:attachment":[{"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/media?parent=572"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/categories?post=572"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gironsec.com\/blog\/wp-json\/wp\/v2\/tags?post=572"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}