AES Encryption Error: Unknown symbol crypto_alloc_base

barunparichha · 02-05-2012, 11:25 PM

aesTest.c

Code:

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/crypto.h>
#define ALG_CCMP_KEY_LEN 16
    int init_module(void)
    {
        struct crypto_cipher *tfm;
        const u8 key[16]= "my key";
        u8 in[20] ="I Love India";
        u8 encrypted[200];
        u8 decrypted[200];
        printk(KERN_INFO ">>>>>>>>aesModule Insmoded>>>>>>>>\n");
        printk(KERN_INFO ">>>>>>>>Plain:%s \n",in);
        tfm = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);

        //if (!IS_ERR(tfm))
                crypto_cipher_setkey(tfm, key, ALG_CCMP_KEY_LEN);

        crypto_cipher_encrypt_one(tfm, encrypted, in);
        printk(KERN_INFO ">>>>Encrypted :%s \n",encrypted);
        crypto_cipher_decrypt_one(tfm, decrypted, encrypted);
        printk(KERN_INFO ">>>>Decrypted :%s \n ",decrypted);


        return 0;
    }

    void cleanup_module(void)
    {
        printk(KERN_INFO ">>>>>>>>aesModule Removed>>>>>>>>\n");
    }

Makefile

Code:

obj-m += aesTest.o

all:
        make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules

clean:
        make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean

Error found:

Code:

#insmod aesTest.ko
aesTest: Unknown symbol crypto_alloc_base
insmod: error inserting 'aesTest.ko': -1 Unknown symbol in module

Any help will be appreciated.
With Thanks,
Barun

barunparichha · 02-06-2012, 11:45 PM

I resolved this issue by adding below code to the end of the module.

Code:

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Barun code for aes encryption test");
MODULE_AUTHOR("Barun Parichha<barun.parichha@gmail.com>");
MODULE_ALIAS("test");

Reason for this error:
http://docs.blackfin.uclinux.org/ker...g/ch09s02.html
symbols exported with EXPORT_SYMBOL(), can only be seen by modules with a MODULE_LICENSE() that specifies a GPL compatible license.

Regards,
Barun