rescue'ing OpenSSL errors

[Robert]

Hi! I'm having some issues with the OpenSSL library:

I'm trying to rescue whatever errors the library wants to throw,
however, it's not working:

def encrypt
require 'openssl'
begin
aes = OpenSSL::Cipher::Cipher.new('AES-128-CBC')
aes.encrypt('SOME_KEY')
cipher = aes.update(password)
cipher << aes.final
return cipher
rescue
return false
end
end

Now I go into irb:

require 'encrypt'

encrypt('test') # -> gives encrypted output
encrypt('') # -> gives error "evp_enc.c(332): OpenSSL internal error,
assertion failed: inl > 0 \n Abort trap"

Seems like I can't rescue that because the error comes from a C
library. Is that right?


Are there any solutions to this, except, for example, checking that
"not password.empty?" ?




Thanks, Rob

 

[Edward Faulkner]

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Seems like I can't rescue that because the error comes from a C =20
library. Is that right?

By default, rescue only catches exceptions that are derived from
StandardError (not Exception). It's possible that OpenSSL is raising
an exception derived directly from Exception.

Try using "rescue Exception" instead of just "rescue".

regards,
Ed

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[Robert]

Hello Edward,

thanks about pointing that out. Another thing learned

However, it does not work. It still throws that same error (and also
quits irb).

Anyway, for me that's not a problem anymore, because I just added:
raise ArgumentError if password.empty?
to my script. But I'm still curious why a "rescue Exception" doesn't
work here -- if anyone knows, that'd be cool


roob

 

[Toby DiPasquale]

Hello Edward,

thanks about pointing that out. Another thing learned

However, it does not work. It still throws that same error (and also
quits irb).

Anyway, for me that's not a problem anymore, because I just added:
raise ArgumentError if password.empty?
to my script. But I'm still curious why a "rescue Exception" doesn't
work here -- if anyone knows, that'd be cool

Your clue is the last part of the error. It appears as if the OpenSSL
library has generated a SIGABRT. Try this:

require 'encrypt'
trap( "ABRT") { puts "abort trapped... dumping out" }
encrypt( 'test')
encrypt( '')

See if that works.