Segmentation fault around MD5 code - c

Question

While I am running this md5 code, it is taking maximum 64 characters length of input at run time. Whenever I am giving more than 64 characters, it is showing
Inconsistency detected by ld.so: dl-fini.c: 205: _dl_fini: Assertion ns != 0 || i == nloaded failed!
I need to hash nearly 10kb of input (only string). Do I need to change anything in the header file? Can anyone tell me solution please?
md5.h
#ifndef HEADER_MD5_H
#define HEADER_MD5_H
#include <openssl/e_os2.h>
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifdef OPENSSL_NO_MD5
#error MD5 is disabled.
#endif
/*
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* ! MD5_LONG has to be at least 32 bits wide. If it's wider, then !
* ! MD5_LONG_LOG2 has to be defined along. !
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
*/
#if defined(__LP64__)
#define MD5_LONG unsigned long
#elif defined(OPENSSL_SYS_CRAY) || defined(__ILP64__)
#define MD5_LONG unsigned long
#define MD5_LONG_LOG2 3
/*
* _CRAY note. I could declare short, but I have no idea what impact
* does it have on performance on none-T3E machines. I could declare
* int, but at least on C90 sizeof(int) can be chosen at compile time.
* So I've chosen long...
* <appro#fy.chalmers.se>
*/
#else
#define MD5_LONG unsigned long
#endif
#define MD5_CBLOCK 64
#define MD5_LBLOCK (MD5_CBLOCK/2)
#define MD5_DIGEST_LENGTH 16
typedef struct MD5state_st
{
MD5_LONG A,B,C,D;
MD5_LONG Nl,Nh;
MD5_LONG data[MD5_LBLOCK];
unsigned int num;
} MD5_CTX;
#ifdef OPENSSL_FIPS
int private_MD5_Init(MD5_CTX *c);
#endif
int MD5_Init(MD5_CTX *c);
int MD5_Update(MD5_CTX *c, const void *data, size_t len);
int MD5_Final(unsigned char *md, MD5_CTX *c);
unsigned char *MD5(const unsigned char *d, size_t n, unsigned char *md);
void MD5_Transform(MD5_CTX *c, const unsigned char *b);
#ifdef __cplusplus
}
#endif
#endif
md5.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "md5.h"
char *pt(char *, int );
int main(int argc, char **argv)
{
char *in;
char *out;
printf("ENter the string\n");
scanf("%[^\n]s",in);
size_t len; //unsigned long len; size_t len;
len = printf("len is %d\n",strlen(in));
out = pt(in, len);
printf("MD5 is\t: %s\n", out);
free(out);
//return 0;
}
char *pt(char *str, int length)
{
int n;
MD5_CTX c;
unsigned char digest[16];
char *output = (char*)malloc(33);
MD5_Init(&c);
MD5_Update(&c, str, length);
MD5_Final(digest, &c);
for (n = 0; n < 16; ++n)
{
sprintf(&output[n*2], "%02x", (unsigned int)digest[n]);
}
return output;
}

Answer 1

Problem 1
For this statement:
scanf("%[^\n]s",in);
When I compile it using the -Wall flag, I get the warning:
warning: 'in' is used uninitialized in this function [-Wuninitialized]
scanf("%[^\n]s",in);
^
As you see, in is not pointing to any location in your memory, so you first need to allocate some memory either with an array or malloc():
char in[500]; //or a higher value
char *out;
printf("Enter the string\n");
scanf("%499[^\n]s", in);
printf("\nin = .%s.\n", in);
or
char *in;
char *out;
in = malloc(500); //or a higher value
printf("Enter the string\n");
scanf("%499[^\n]s", in);
printf("\nin = .%s.\n", in);
Possible problem 2
You are assigning the return from printf() to the variable len.
len = printf("len is %d\n",strlen(in));
Return value printf:
Upon successful return, it returns the number of characters printed (excluding the null byte used to end output to strings).
Assuming you want the variable len to contain the length of the string in and not the number of characters printed by printf("len is %d\n",strlen(in)), you might want to assign the return from strlen() first:
len = strlen(in);
printf("len is %d\n", len);