Problem with a Crypto Library

[mpre]

Hi...
I'm new in this forum, but I like it a lot...

I've a problem with my new project, I need to do "hmac-sha1" of a part of a file and put the first 16 values of that hash in a new file...

I've found a libray on "koders" (i don't know if I can post here the link, if I can, I will post it in the next post).

But if I try to compile it, I will receive this error:

[mpre@mpre-probook e-sec_min]$ gcc e-sec_min.c -o esec
/tmp/ccn86muF.o: In function `rehash_sec':
e-sec_min.c:(.text+0x234): undefined reference to `hmac_sha1'
collect2: ld returned 1 exit status

In attachment I will put my directory where there are all the file needed by the program.

Can any of you help me to make working that function?

[grumpy]

That error message is from the linker, not the compiler. It is not finding the symbol (presumably corresponding to a function) named hmac_sha1

Try adding the name of the library to the gcc command line. Functions in third-party libraries (like the one you found on "koders") are not found by magic. Possibly read the documentation for the library for specific information on how to link against the library.

[mpre]

Thank you for the info... I never used external library befor now...
I've tried this command:

gcc e-sec_min.c hmac-sha1.c hmac.h hmac-md5.c sha1.c sha1.h md5.h md5.c memxor.h memxor.c unlocked-io.h -o esec

and something is changed... now there are an error on memxor.h:

memxor.h:29:30: error: expected ‘;’, ‘,’ or ‘)’ before ‘dest’

This is memxor.h:

#ifndef MEMXOR_H# define MEMXOR_H


#include <stddef.h>


/* Compute binary exclusive OR of memory areas DEST and SRC, putting
   the result in DEST, of length N bytes.  Returns a pointer to
   DEST. */
void *memxor (void *restrict dest, const void *restrict src, size_t n);


#endif /* MEMXOR_H */

It generate me the file "esec" but if I try to launch it i will receive:

[root@mpre-probook e-sec_min]# ./esecbash: ./esec: cannot execute binary file

What I'm doing wrong?

Thank you very mutch

[grumpy]

restrict is a keyword first introduced by the 1999 C standard. It was not supported by older versions of C, and is also not supported in C++.

The option to get gcc to support the 1999 C standard (rather than 1989 standard plus a few later corrections) is -std=c99. Bear in mind that the support in gcc for 1999 standard C is incomplete.

By the way, it is not necessary to list header files (.h extension) on the gcc command line. They are files that are #include'd by other files.

[mpre]

Thank you all for the help, now i have compiled my program.

But, now I need another little help:

I need to convert a string to hex values... Let me explane.

I've

char a[16]="123456789abcdef0"

and I need

char a[8]={0x12,0x34,0x56,0x78,0x9a,0xbc,0xde,0xf0}

How I can do this?

[memcpy]

It wouldn't be an array of char pointers, it would just be an array of chars, OR a char pointer:

char *a;
/* or */
char a[16];

[mpre]

Yes, I copyed wrong, i used

char a[16]