On Mon, 2020-09-07 at 20:59 -0700, Eric Biggers wrote: > On Fri, Sep 04, 2020 at 12:05:26PM -0400, Jeff Layton wrote: > > Once we allow encrypted filenames on ceph we'll end up with names that > > may have illegal characters in them (embedded '\0' or '/'), or > > characters that aren't printable. > > > > It will be safer to use strings that are printable. It turns out that the > > MDS doesn't really care about the length of filenames, so we can just > > base64 encode and decode filenames before writing and reading them. > > > > Lift the base64 implementation that's in fscrypt into lib/. Make fscrypt > > select it when it's enabled. > > > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > > --- > > fs/crypto/Kconfig | 1 + > > fs/crypto/fname.c | 64 ++------------------------------ > > include/linux/base64_fname.h | 11 ++++++ > > lib/Kconfig | 3 ++ > > lib/Makefile | 1 + > > lib/base64_fname.c | 71 ++++++++++++++++++++++++++++++++++++ > > 6 files changed, 90 insertions(+), 61 deletions(-) > > create mode 100644 include/linux/base64_fname.h > > create mode 100644 lib/base64_fname.c > > > > I'm still concerned that this functionality is too specific to belong in lib/ at > the moment, given that it's not the most commonly used variant of base64. How > about keeping these functions in fs/crypto/ for now? You can call them > fscrypt_base64_encode() and fscrypt_base64_decode() and export them for ceph to > use. > Ok, will do. > > diff --git a/lib/base64_fname.c b/lib/base64_fname.c > > new file mode 100644 > > index 000000000000..7638c45e4035 > > --- /dev/null > > +++ b/lib/base64_fname.c > > @@ -0,0 +1,71 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Modified base64 encode/decode functions, suitable for use as filename components. > > + * > > + * Originally lifted from fs/crypto/fname.c > > + * > > + * Copyright (C) 2015, Jaegeuk Kim > > + * Copyright (C) 2015, Eric Biggers > > + */ > > Please don't change the copyright statements. The original file had: > > * Copyright (C) 2015, Google, Inc. > * Copyright (C) 2015, Motorola Mobility -- Jeff Layton <jlayton@xxxxxxxxxx>
