You can use “rsautl” to encrypt and decrypt small message files but when it comes to large files it’ll shows the error as bellow
Error:
RSA operation error
6408:error:0406D06E:rsa routines:RSA_padding_add_PKCS1_type_2:data too large for
key size:./crypto/rsa/rsa_pk1.c:151:
So it’s better to use SMIME to perform large file Encryption.
Generate private and public key pairs:
openssl req -x509 -nodes -days 1000 -newkey rsa:1024 -keyout pri.pem -out pub.pem
Encrypt Large File:
openssl smime -encrypt -aes256 -in w.txt -binary -outform DEM -out w.ssl pub.pem
Decrypt Large File:
openssl smime -decrypt -in w.ssl -binary -inform DEM -inkey pri.pem -out w.txt
Here,
w.txt is the any Large file
w.ssl is the Encrypted File
pri.pem, pub.pem is the generated private-key and public-key respectively
Thanks