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@amlweems
Created January 27, 2015 17:32
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ghost.c
/*
* Qualys test program to check for presence of GHOST vulnerability
* For more info: http://www.openwall.com/lists/oss-security/2015/01/27/9
*/
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#define CANARY "in_the_coal_mine"
struct {
char buffer[1024];
char canary[sizeof(CANARY)];
} temp = { "buffer", CANARY };
int main(void) {
struct hostent resbuf;
struct hostent *result;
int herrno;
int retval;
/*** strlen (name) = size_needed - sizeof (*host_addr) - sizeof (*h_addr_ptrs) - 1; ***/
size_t len = sizeof(temp.buffer) - 16*sizeof(unsigned char) - 2*sizeof(char *) - 1;
char name[sizeof(temp.buffer)];
memset(name, '0', len);
name[len] = '\0';
retval = gethostbyname_r(name, &resbuf, temp.buffer, sizeof(temp.buffer), &result, &herrno);
if (strcmp(temp.canary, CANARY) != 0) {
puts("vulnerable");
exit(EXIT_SUCCESS);
}
if (retval == ERANGE) {
puts("not vulnerable");
exit(EXIT_SUCCESS);
}
puts("should not happen");
exit(EXIT_FAILURE);
}
@xsuperbug
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Ubuntu EGLIBC 2.19-0ubuntu6.3 >> not vulnerable

@ejangi
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ejangi commented Jan 28, 2015

Mac 10.10.2 returns errors, so I'm assuming there's no glibc at all...

gistfile1.c:30:12: warning: implicit declaration of function 'gethostbyname_r' is invalid in
      C99 [-Wimplicit-function-declaration]
  retval = gethostbyname_r(name, &resbuf, temp.buffer, sizeof(temp.buffer), &result, &herrno);
           ^
1 warning generated.
Undefined symbols for architecture x86_64:
  "_gethostbyname_r", referenced from:
      _main in gistfile1-00b79d.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

@flaviocysne
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By reading this post I think that gethostbyname and gethostbyname2 should be the equivalent to gethostbyname_r, on MacOS

@flaviocysne
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(Ubuntu EGLIBC 2.15-0ubuntu10.10) 2.15 >> not vulnarable

@flaviocysne
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$ uname -a
Linux xxxxx 2.6.18-348.6.1.el5xen #1 SMP Tue May 21 16:10:52 EDT 2013 x86_64 x86_64 x86_64 GNU/Linux

$ ldd --version
ldd (GNU libc) 2.5

$ gcc --version
gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-52)

VULNARABLE

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