I'm having troubles using libcrypto in a shared library. Here is what I
did:
1. I'm on RedHat 7.2
2. I installed OpenSSL by "./config shared" and got
/usr/local/ssl/lib/libcrypto.so
3. I wrote a sample library calling EVA functions (the library source
attached below - decrypt.c)
4. I compiled the decrypt.c as follows:
gcc -fpic -c decrypt.c -o decrypt.o -I/usr/local/ssl/include
gcc -shared decrypt.o -o libdecrypt.so -L/usr/local/ssl/lib
-lcrypto
5. I added current and the OpenSSL directories to the library
path:
LD_LIBRARY_PATH=$(pwd):/usr/local/ssl/lib
When I try to run the testlib program (source attached below) the
program fails on dlopen()
Could someone please advise, what am I doing wrong?
Thanks in advance
// decrypt.c
#include "testlib.h"
#include <stdio.h>
#include
<openssl/evp.h>
#include <fcntl.h>
int test_decrypt(){
int > int encfd;
unsigned char
outbuf[1032];
int olen, tlen, n;
char
inbuff[1032];
EVP_CIPHER_CTX ctx;
unsigned char
key[16];
unsigned char iv[8];
char *encfile =
"blowfish_enc";
memset (&key, 0, 16);
memset (&iv, 0,
8);
strcpy(key,"1234567890123456");
strcpy(iv,"12345678");
if ((encfd = open (encfile,
O_RDONLY)) == -1) {
return onerr;
}
memset (&inbuff, 0, sizeof(inbuff));
if ((n = read
(encfd, inbuff, sizeof(inbuff))) == -1) {
close(encfd);
return
onerr;
}
close (encfd);
EVP_CIPHER_CTX_init (&ctx);
EVP_DecryptInit
(&ctx, EVP_bf_cbc (), key, iv);
memset (&outbuf, 0, sizeof(outbuf));
if
(EVP_DecryptUpdate (&ctx, outbuf, &olen, inbuff, n) != 1)
{
return onerr;
}
if (EVP_DecryptFinal
(&ctx, outbuf + olen, &tlen) != 1) {
return
onerr;
}
olen += tlen;
printf("Output: %s", outbuf);
return 0;
}
// testlib.c
#include <stdio.h>
#include <stdlib.h>
#include
<unistd.h>
#include <dlfcn.h>
int main(int argc, char **argv)
{
void
*handle;
int (*test_decrypt)(void);
char *c;
handle = dlopen("libdecrypt.so", 1);
c =
dlerror();
if(c)
{
fprintf(stderr, "couldnt
open library\n");
abort();
}
test_decrypt =
dlsym(handle, "test_decrypt");
c =
dlerror();
if(c)
{
fprintf(stderr, "couldnt
get function
symbol\n");
abort();
}
test_decrypt();
dlclose(handle);
return
0;
}
