the max size of ifle of openssl encrypt with

[yangk]

Hi all
Do you the max size of file that can be encrypted with openssl 0.9.8k?

Thanks!

[kobylka]

Hello yangk!

The SSL protocol is part of the Application Layer, thus it lies on top of the rest of the protocol. In case of TCP/IP if a large file is to be transmitted to another end it will take care of fragmentation (split the "file" up into smaller pieces) so don't worry about file size transmission since this is the task of the underlying protocols.


Kind regards,

Kobylka

[Steven Schweda]

> [...] the underlying protocols.

Not relevant?

I assume that you mean something like the
(non-network-related) scheme described at:

http://www.openssl.org/docs/apps/enc.html

You'd need to see how your "openssl 0.9.8k"
was built, but I'd expect the builders to
enable large-file support where it is
available, so I'd guess that you probably
have nothing to worry about.

My advice would be to run a test on a file
bigger than 2GB, and on a file bigger than
4GB, and see what happens. If those work,
then I'd expect no problems related to file
size (until your disks fill).

As usual, the answer might depend on the
properties of the system on which you're
running this software, about which we know
nothing. A problem report or question which
lacks "uname -a" output generally isn't worth
much.

[yangk]

Hi

I use the command to encrypt files, just like
openssl enc -blowfish -e -in infile -out outfile

So I just want to know the max size of infile, and I also do some tests to encrypt files bigger than 2GB and 4GB :
1.openssl enc -blowfish -e -in 2gbfile -out 2gbfile.enc
2.openssl enc -blowfish -e -in 4gbfile -out 4gbfile.enc

It seems that the above tests can work fine.

So does it mean that it has no max size of file to be encrypted.
Thanks!

[yangk]

hi Steven Schweda

my machine is HP-UX B.11.11 U 9000/800

[Steven Schweda]

> So does it mean that it has no max size of
> file to be encrypted.

It's not proof, but it's pretty good
evidence. It would be even better if you can
make output files which are also large (>2GB
or >4GB).

> my machine is HP-UX B.11.11 U 9000/800

So the OS itself should have no problems
dealing with large files.

[yangk]

hi Steven Schweda,

Is there any macro defined to limit the max size of files to be encrypted?

And the file after encrypted is a little bigger.

[kobylka]

Hi!

I think I totally missed the question about the file size in my first post...

Just to add some info, in any openssl supported HP-UX version with large file support openssl will always be compiled by default with large file support.

> Do you the max size of file that can be encrypted with openssl 0.9.8k?

If what you need is to limit the size of the file passed to the openssl utility you could easily add the necessary code and recompile.


Kind regards,

Kobylka

[Steven Schweda · Accepted solution]

> Is there any macro defined to limit the max
> size of files to be encrypted?

I doubt it. Why would there be one?

> And the file after encrypted is a little
> bigger.

If the program can read and write large
files (>2GB and >4GB), then I would not
expect any file-size-related problems (until
you fill a disk, or run into some OS or
file-system limit).

The big change (years ago) was from a 32-bit
value for file size/offset to a 64-bit value.
A program which is using 32-bit values should
see a sign change at 2GB and/or an overflow
at 4GB. If you don't see problems at these
file sizes, then there's no reason to expect
size-related problems at any (reasonable)
file size.

[yangk]

Hi Steven Schweda

Thank you very much! I have already figure
out this problem. It is just due to the limit of OS.