libtomcrypt usage benchmarking - c

Question

I wanted to compare AES algorithm performance from libtomcrypt in Windows and Ubuntu by creating a benchmark-like file, but I have got errors while coding it. Please help me. Below is my file for comparing:
Compare.c:
`#include <time.h> `
#include <tomcrypt.h>
#define MIN_TIME 10.0
#define MIN_ITERS 20 `
double test_rijndael_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey) {
int iterations = 0;
clock_t start;
double elapsed=0.0;
int out;
start=clock();
do{
out = rijndael_ecb_encrypt(pt, ct, skey);
iterations++;
elapsed=(clock()-start)/(double)CLOCKS_PER_SEC;
} while(elapsed<MIN_TIME || iterations<MIN_ITERS);
elapsed=1000.0*elapsed/iterations;
printf("%s \n",pt);
printf("%s \n",skey->data);
printf("%s \n",ct);
printf("iterations: %8d \n",iterations);
printf("%8.2lf ms per iteration \n",elapsed);
printf("out: %d \n",out);
return elapsed;
}
int main() {
unsigned char pt[22]="-K4)<i50~'APg2fa7DiV";
unsigned char ct[22];
unsigned char key[16]="EDB1C6D13FC72";
symmetric_key *skey;
int err;
double tout1;
printf("%x",sizeof(pt));
printf("%l",sizeof(key));
if((err=rijndael_setup(key,16,0,skey))!=CRYPT_OK) {
printf("%s",error_to_string(err));
return -1;
}
tout1=test_rijndael_ecb_encrypt(pt,ct,skey);
printf("%s \n",ct);
printf("%f",tout1);
return 0;
}
But when I compile this it shows runtime errors as:
gcc -o "TestC" ./src/TestC.o
./src/TestC.o: In function `test_rijndael_ecb_encrypt':
/home/anvesh/workspace/TestC/Debug/../src/TestC.c:27: undefined reference to `rijndael_ecb_encrypt'
./src/TestC.o: In function `test_rijndael_ecb_decrypt':
/home/anvesh/workspace/TestC/Debug/../src/TestC.c:53: undefined reference to `rijndael_ecb_decrypt'
./src/TestC.o: In function `main':
/home/anvesh/workspace/TestC/Debug/../src/TestC.c:82: undefined reference to `rijndael_setup'
/home/anvesh/workspace/TestC/Debug/../src/TestC.c:83: undefined reference to `error_to_string'
collect2: error: ld returned 1 exit status
make: *** [TestC] Error 1
Where did I go wrong?

Answer 1

You forgot to link with tomcrypt library. Compile with -ltomcrypt to link the library:
gcc file.c -ltomcrypt