In 2013, I wrote "Cryptohash benchmarks 90 to 101% faster than external
hashers". Re-benchmarking today, I found cryptonite's sha256 consistently
outperformed coreutils by 10% for large files. Tested 10 mb, 100 mb, 1 gb
files with both sha256 and sha512. And for smaller files, the external
process startup time swamps the hash time.
Perhaps cryptonite has improved. Or it could just do better on my
current CPU Intel(R) Pentium(R) CPU 4410Y @ 1.50GHz). Anyway, even if cryptonite
is slower in some situations, seems likely it would only be marginally slower;
it's got the same class of highly optimised C code under the hood as coreutils.
The main difference between the two sha256 implementations seems to be
how much of the inner loop they unroll..
This commit was sponsored by Henrik Riomar on Patreon.
* migrate: Fix bug in migration between eg SHA256 and SHA256E,
that caused the extension to be included in SHA256 keys,
and omitted from SHA256E keys.
(Bug introduced in version 6.20170214)
* migrate: Check for above bug when migrating from SHA256 to SHA256
(and same for SHA1 to SHA1 etc), and remove the extension that should
not be in the SHA256 key.
* fsck: Detect and warn when keys need an upgrade, either to fix up
from the above migrate bug, or to add missing size information
(a long ago transition), or because of a few other past key related
bugs.
This commit was sponsored by Henrik Riomar on Patreon.
Some blake hash varieties were not yet available in that version.
Rather than tracking exact details of what cryptonite supported when,
disable blake unless using a current cryptonite.
There are a lot of different variants and sizes, I suppose we might as well
export all the common ones.
Bump dep to cryptonite to 0.16, earlier versions lacked BLAKE2 support.
Even android has 0.16 or newer.
On Debian, Blake2bp_512 is buggy, so I have omitted it for now.
http://bugs.debian.org/892855
This commit was sponsored by andrea rota.
Do not treat parts of the filename that contain punctuation or other
non-alphanumeric characters as extensions. Before, such characters were
filtered out.
Note that in 45308ec78b "foo.ba__________r"
was munged to ".bar" and so incorrectly treated as an extension. That was
fixed by changing the filter order, but not allowing punctuation seems a
better fix.
This assumes that extensions containing punctuation are rare. "_" seems the
most likely character; I used it in ikiwiki "._comment" files. But I can't
recall seeing it anywhere else. It certianly seems that no commonly used
extensions contain punctuation. If git-annex doesn't treat "._comment"
as an extension, it's not likely to break software that expects to see that
extension like some software expects to see .epub or .mp3.
This commit was sponsored by Jack Hill on Patreon.
This avoids warnings from stack about the module not being listed in the
cabal file. So, the generated file is also renamed to Build/SysConfig.
Note that the setup program seems to be cached despite these changes; I
had to cabal clean to get cabal to update it so that Build/SysConfig was
written.
This commit was sponsored by Jochen Bartl on Patreon.
To work around the problem that the external special remote protocol does
not support keys containing spaces.
This commit was sponsored by Denis Dzyubenko on Patreon.
Cryptonite is faster and allocates less, and I want to get rid of
MissingH use.
Note that the new dependency on memory is free; it's a dependency of
cryptonite.
This commit was supported by the NSF-funded DataLad project.
Where before the "name" of a key and a backend was a string, this makes
it a concrete data type.
This is groundwork for allowing some varieties of keys to be disabled
in file2key, so git-annex won't use them at all.
Benchmarks ran in my big repo:
old git-annex info:
real 0m3.338s
user 0m3.124s
sys 0m0.244s
new git-annex info:
real 0m3.216s
user 0m3.024s
sys 0m0.220s
new git-annex find:
real 0m7.138s
user 0m6.924s
sys 0m0.252s
old git-annex find:
real 0m7.433s
user 0m7.240s
sys 0m0.232s
Surprising result; I'd have expected it to be slower since it now parses
all the key varieties. But, the parser is very simple and perhaps
sharing KeyVarieties uses less memory or something like that.
This commit was supported by the NSF-funded DataLad project.
Turns out that Data.List.Utils.split is slow and makes a lot of
allocations. Here's a much simpler single character splitter that behaves
the same (even in wacky corner cases) while running in half the time and
75% the allocations.
As well as being an optimisation, this helps move toward eliminating use of
missingh.
(Data.List.Split.splitOn is nearly as slow as Data.List.Utils.split and
allocates even more.)
I have not benchmarked the effect on git-annex, but would not be surprised
to see some parsing of eg, large streams from git commands run twice as
fast, and possibly in less memory.
This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.
Fixes a minor fd leak, never more than 1 in normal use,
which broke the test suite when I tried to write to
a file that was still open for a previous hashing.
sideAction is for things not generally related to the current action being
performed. And, it adds a newline after the side action. This was not the
right thing to use for stuff like "checksum", where doing a checksum is
part of the git annex get process, and indeed we want it to display
"(checksum...) ok"
While cryptohash has SHA3 support, it has not been updated for the final
version of the spec. Note that cryptonite has not been ported to all arches
that cryptohash builds on yet.
This way, if a system's sha1sum etc is broken, it will be tried if
git-annex was built to use it, but at least it will fall back to using
internal hashing when it fails.
A side benefit of this is that hashFile consistently throws an IOError if
the file is unable to be read. In particular, if the disk is failing with
IO errors, and external hash command is used, it used to throw a user error
with the error message from externalSHA. Now, the external hash command
will fail, that message will be printed as a warning, and it'll fall back
to the internal hash command. If the disk IO error is not intermittent, it
will re-occur, and so an IOError will be thrown.
Of course, this can mean it reads a file twice, but only in edge cases.
This is especially useful because the caller doesn't need to generate valid
url keys, which involves some escaping of characters, and may involve
taking a md5sum of the url if it's too long.
Avoid using fileSize which maxes out at just 2 gb on Windows.
Instead, use hFileSize, which doesn't have a bounded size.
Fixes support for files > 2 gb on Windows.
Note that the InodeCache code only needs to compare a file size,
so it doesn't matter it the file size wraps. So it has been
left as-is. This was necessary both to avoid invalidating existing inode
caches, and because the code passed FileStatus around and would have become
more expensive if it called getFileSize.
This commit was sponsored by Christian Dietrich.
This fixes all instances of " \t" in the code base. Most common case
seems to be after a "where" line; probably vim copied the two space layout
of that line.
Done as a background task while listening to episode 2 of the Type Theory
podcast.
This only performs some basic tests so far; no testing of chunking or
resuming. Also, the existing encryption type of the remote is used; it
would be good later to derive an encrypted and a non-encrypted version of
the remote and test them both.
This commit was sponsored by Joseph Liu.
Needed for resuming from chunks.
Url keys are considered not stable. I considered treating url keys with a
known size as stable, but just don't feel that is enough information.
Added new fields for chunk number, and chunk size. These will not appear
in normal keys ever, but will be used for chunked data stored on special
remotes.
This commit was sponsored by Jouni K Seppanen.
Note that the hash backends were made to stop printing a (checksum..)
message as part of this, since it showed up without a file when deciding
whether to act on a file. Should have probably removed that message a while
ago anyway, I suppose.
FAT has a lot of characters it does not allow in filenames, like ? and *
It's probably the worst offender, but other filesystems also have
limitiations.
In 2011, I made keyFile escape : to handle FAT, but missed the other
characters. It also turns out that when I did that, I was also living
dangerously; any existing keys that contained a : had their object
location change. Oops.
So, adding new characters to escape to keyFile is out. Well, it would be
possible to make keyFile behave differently on a per-filesystem basis, but
this would be a real nightmare to get right. Consider that a rsync special
remote uses keyFile to determine the filenames to use, and we don't know
the underlying filesystem on the rsync server..
Instead, I have gone for a solution that is backwards compatable and
simple. Its only downside is that already generated URL and WORM keys
might not be able to be stored on FAT or some other filesystem that
dislikes a character used in the key. (In this case, the user can just
migrate the problem keys to a checksumming backend. If this became a big
problem, fsck could be made to detect these and suggest a migration.)
Going forward, new keys that are created will escape all characters that
are likely to cause problems. And if some filesystem comes along that's
even worse than FAT (seems unlikely, but here it is 2013, and people are
still using FAT!), additional characters can be added to the set that are
escaped without difficulty.
(Also, made WORM limit the part of the filename that is embedded in the key,
to deal with filesystem filename length limits. This could have already
been a problem, but is more likely now, since the escaping of the filename
can make it longer.)
This commit was sponsored by Ian Downes
SHA3 is still waiting for final standardization.
Although this is looking less likely given
https://www.cdt.org/blogs/joseph-lorenzo-hall/2409-nist-sha-3
In the meantime, cryptohash implements skein, and it's used by some of the
haskell ecosystem (for yesod sessions, IIRC), so this implementation is
likely to continue working. Also, I've talked with the cryprohash author
and he's a reasonable guy.
It makes sense to have an alternate high security hash, in case some
horrible attack is found against SHA2 tomorrow, or in case SHA3 comes out
and worst fears are realized.
I'd also like to support using skein for HMAC. But no hurry there and
a new version of cryptohash has much nicer HMAC code, so I will probably
wait until I can use that version.
