A fast way to generate new OSTree content using an existing
tree is to checkout (as hard links), add/replace files, then
call `ostree_repo_scan_hardlinks()`, then commit.
But `ostree_repo_scan_hardlinks()` scans the entire repo, which
can be slow if you have a lot of content.
All we really need is a mapping of (device,inode) -> checksum
just for the objects we checked out, then use that mapping
for commits.
This patch adds API so that callers can create a mapping via
`ostree_repo_devino_cache_new()`, then pass it to
`ostree_repo_checkout_tree_at()` which will populate it, and then
`ostree_repo_write_directory_to_mtree()` can consume it.
I plan to use this in rpm-ostree for package layering work.
Notes:
- The old `ostree_repo_scan_hardlinks()` API still works.
- I tweaked the cache to be a set with the checksum colocated with
the key, to avoid a separate malloc block per entry.
https://github.com/GNOME/ostree/pull/167
Concurrent pulls break since we're sharing the staging directory for
all transactions in the repo. This makes us use a per-transaction directory.
However, in order for resumes to work we first look for existing
staging directories and try to aquire an exclusive lock for them. If
we can't find any staging directory or they are all already locked,
then we create a new one.
https://bugzilla.gnome.org/show_bug.cgi?id=757611
ostree_repo_write_commit_with_time() converts the timestamp to
big-endian byte order.
ostree_repo_write_commit() was also doing this when calling
ostree_repo_write_commit_with_time(), resulting in a corrupted
commit object (timestamp bytes were backwards).
Recent regression in 14ffd7022a
Do not delete a .commitmeta file after removing the last metadata entry.
This way a client will pull the empty .commitmeta file and overwrite old
metadata as expected.
https://bugzilla.gnome.org/750459
Also renames OstreeRepoTrustedContentBareCommit to
OstreeRepoContentBareCommit so that it can be used by both.
This will be needed when we introduce checksum verification of objects
in static deltas.
When a commit is deleted and the repo is configured to use tombstone
commits, create one. Delete the tombstone file only if the commit is
pulled again.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
This originally was a way that we detected the case where a pull was
interrupted. Later, we added `.commitpartial` files which also cover
this case.
See also https://github.com/GNOME/ostree/pull/85
We still want to honor their existence (and unlink them) in case an
old version of ostree was in use, but I believe it's safe to stop
creating them now.
The only case where this would break is if you have a version of
ostree that predates commitpartial in your rollback history, but such
old versions are no longer in use by operating systems I support at
least.
Closes: https://github.com/GNOME/ostree/pull/100
I was hitting a bug in libguestfs/guestmount/FUSE where it blew up
with EINVAL on directories containing lots of files (more than
32000?). We really want to use prefixed subdirs just like the real
objects/ directory does.
This allows us to share more code between the paths, is more
efficient, etc.
gnome-continuous uses the ostree_repo_scan_hardlinks() mode to
avoid re-checksumming everything. However, when I ported the commit
code to use openat() and friends, this optimization was lost.
Re add it. The difference is about 15s versus 5 minutes.
When doing a pull --mirror from an archive-z2 repository into another
archive-z2 repository, currently we gunzip/checksum/gzip each content
object. The re-gzip process in particular is fairly expensive.
This does assume that the upstream content is trusted and correct.
It'd be nice in the future to do at least a CRC check, if not the full
checksum. (Could we append CRC data to the end of filez objects?)
We could also choose to only do this optimization if fetching over
TLS.
before: 1626 metadata, 20320 content objects fetched; 299634 KiB transferred in 62 seconds
after : 1626 metadata, 20320 content objects fetched; 299634 KiB transferred in 11 seconds
For future delta work where we do more interesting things than just
"tar of new objects", this lays the groundwork for doing streaming
writes into content objects.
It's also more efficient, as we avoid many intermediate allocations
and virtual calls. Just a single `g_output_stream_write_all` for the
splice case.
Conflicts:
src/libostree/ostree-repo-private.h
src/libostree/ostree-repo-static-delta-processing.c
Do not write directly to objects/ but maintain pulled files under tmp/
with a "tmpobject-$CHECKSUM.$OBJTYPE" name until they are syncfs'ed to
disk.
Move them under objects/ at ostree_repo_commit_transaction cleanup
time.
Before (test done on a local network):
$ LANG=C sudo time ./ostree --repo=repo pull origin master
0 metadata, 3 content objects fetched; 83820 KiB; 4 delta parts
fetched, transferred in 417 seconds
16.42user 6.73system 6:57.19elapsed 5%CPU (0avgtext+0avgdata
248428maxresident)k
24inputs+794472outputs (0major+233968minor)pagefaults 0swaps
After:
$ LANG=C sudo time ./ostree --repo=repo pull origin master
0 metadata, 3 content objects fetched; 83820 KiB; 4 delta parts
fetched, transferred in 9 seconds
14.70user 2.87system 0:09.99elapsed 175%CPU (0avgtext+0avgdata
256168maxresident)k
0inputs+794472outputs (0major+164333minor)pagefaults 0swaps
https://bugzilla.gnome.org/show_bug.cgi?id=728065
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
If an object already existed and we somehow tried to pull it, the
caller would still expect a returned checksum.
This appears to happen with static deltas for some reason; we might be
including duplicate metadata objects. Regardless, this is a bug that
should be fixed.
This is just an efficiency optimization. We're getting fairly close
to all of the hot code paths using `*at()`.
Note that we end up maintaining a half-duplicate code path set here,
because we still need to support commits from an arbitrary GFile *,
which in a possible common case is an OSTree commit.
I think it's worth it though.
This format is pretty much the same as the "bare" format, except the
file ownership and xattrs is not stored in the actual filesystem object, but
rather on the side in a user xattr. This means two things:
1) An unprivileged user can store such a repo independent of the types
of files in it or their xattrs. And you can later (as root)
reconstruct the real filesystem tree with ownership. Although you
can't do that using hardlink-sharing. This also means ostree
fsck does a full verification.
2) Such a repository can be checked out with user-mode (checkout -U)
as an unprivileged user using hardlinks for space sharing.
Additionally, symlinks are stored as regular files (with the content
being the symlink target) because user xattrs are not supported on
symlinks. We know at checkout time if the file is a symlink because
the original st_mode is stored in the xattr metadata.
https://bugzilla.gnome.org/show_bug.cgi?id=741125
Some package systems need to be run as root, so the process linking to
libostree may also be root. However, it's reasonable to have the
target repository be owned by a uid other than root.
This patch makes it Just Work by chowning the file content to match.
Note this only operates on archive-z2 repositories, because you can't
usefully serve bare repositories via HTTP.
https://bugzilla.gnome.org/show_bug.cgi?id=738954
We were using unsigned size when we should have been using signed,
this means we basically weren't checking for errors on write...ouch.
Luckily if we e.g. hit ENOSPC during a pull, the checksums wouldn't
match and we'd return an error anyways. However when writing an
object, we'd end up silently ignoring it =/
https://bugzilla.gnome.org/show_bug.cgi?id=732020
If fetching GPG-signed commits over plain HTTP, a MitM attacker can
fill up the drive of targets by simply returning an enormous stream
for the commit object.
Related to this, an attacker can also cause OSTree to perform large
memory allocations by returning enormous GVariants in the metadata.
This helps close that attack by limiting all metadata objects to 10
MiB, so the initial fetch will be truncated.
But now the attack is only slightly more difficult as the attacker
will have to return a correctly formed commit object, then return a
large stream of < 10 MiB dirmeta/dirtree objects.
https://bugzilla.gnome.org/show_bug.cgi?id=725921
The current "transaction" symlink was introduced to fix issues with
interrupted pulls; normally we assume that if we have a metadata
object, we also have all objects to which it refers.
There used to be a "summary" which had all the available refs, but I
deleted it because it wasn't really used, and was still racy despite
the transaction bits.
We still want the pull process to use the transaction link, so don't
delete the APIs, just relax the restriction on object writing, and
introduce a new ostree_repo_set_ref_immediate().
This is a bit more efficient in that we're not walking full paths, and
it helps avoid security/reliability issues if an attacker (or just a
misbehaving process) has the ability to mutate paths in the middle.
Colin Walters
Alexander Larsson
Matthew Barnes
Giuseppe Scrivano
Cosimo Cecchi
Daniel Svensson