Is it compatible with Google Authenticator? about libcotp HOT 5 CLOSED

Try without base32 encoding K.

from libcotp.

Good to know :)
In the meanwhile, I have released v1.0.9. This release will help to prevent such cases in the future.

from libcotp.

Hi,
yes, it's compatible with Google Authenticator. Please keep in mind that most of the times the secret a website gives you is already base32 encoded.
For example, if you go to this website you have to pass to the get_totp function the upper case letters secret written at the bottom of the page.

Thanks for the input though. I will think a way to handle such cases.
If you have any suggestion just let me know :)

from libcotp.

Hi, Thanks for replying. I have tried your library with below code, but it is not working with Google Authenticator,

#include <stdio.h>
#include <baseencode.h>
#include "cotp.h"

#define K "RJB4USNOCNWGHNEF"

int main()
{
    char *K_base32 = base32_encode(K, strlen(K)+1);
    printf( "%s\n", K_base32 );

    printf( "%s\n", get_totp( K_base32, 6, SHA1 ) );
    //printf( "%s\n", get_totp( K_base32, 6, SHA256 ) );
    //printf( "%s\n", get_totp( K_base32, 6, SHA512 ) );
}

The codes from Google Authenticator is not matching with this.
I compile with

gcc -g3 -O0 -lcrypto totp.c 1.c

root@debian7-x64:/totp# uname -a
Linux debian7-x64 3.2.0-4-amd64 #1 SMP Debian 3.2.41-2 x86_64 GNU/Linux
root@debian7-x64:/totp# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/7/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 7.2.0-6' --with-bugurl=file:///usr/share/doc/gcc-7/README.Bugs --enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr --with-gcc-major-version-only --program-suffix=-7 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie --with-system-zlib --with-target-system-zlib --enable-objc-gc=auto --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-offload-targets=nvptx-none --without-cuda-driver --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 7.2.0 (Debian 7.2.0-6)

Appreciate your help on this..

from libcotp.

@paolostivanin you are awesome. It works now!
Tried this before posting the above comment, but had a seg-fault; that turns out to be because of different issue.
Thanks a lot!!

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