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4083 commits

Author SHA1 Message Date
Eelco Dolstra c4d7c76b64
Recursive Nix support
This allows Nix builders to call Nix to build derivations, with some
limitations.

Example:

  let nixpkgs = fetchTarball channel:nixos-18.03; in

  with import <nixpkgs> {};

  runCommand "foo"
    {
      buildInputs = [ nix jq ];
      NIX_PATH = "nixpkgs=${nixpkgs}";
    }
    ''
      hello=$(nix-build -E '(import <nixpkgs> {}).hello.overrideDerivation (args: { name = "hello-3.5"; })')

      $hello/bin/hello

      mkdir -p $out/bin
      ln -s $hello/bin/hello $out/bin/hello

      nix path-info -r --json $hello | jq .
    ''

This derivation makes a recursive Nix call to build GNU Hello and
symlinks it from its $out, i.e.

  # ll ./result/bin/
  lrwxrwxrwx 1 root root 63 Jan  1  1970 hello -> /nix/store/s0awxrs71gickhaqdwxl506hzccb30y5-hello-3.5/bin/hello

  # nix-store -qR ./result
  /nix/store/hwwqshlmazzjzj7yhrkyjydxamvvkfd3-glibc-2.26-131
  /nix/store/s0awxrs71gickhaqdwxl506hzccb30y5-hello-3.5
  /nix/store/sgmvvyw8vhfqdqb619bxkcpfn9lvd8ss-foo

This is implemented as follows:

* Before running the outer builder, Nix creates a Unix domain socket
  '.nix-socket' in the builder's temporary directory and sets
  $NIX_REMOTE to point to it. It starts a thread to process
  connections to this socket. (Thus you don't need to have nix-daemon
  running.)

* The daemon thread uses a wrapper store (RestrictedStore) to keep
  track of paths added through recursive Nix calls, to implement some
  restrictions (see below), and to do some censorship (e.g. for
  purity, queryPathInfo() won't return impure information such as
  signatures and timestamps).

* After the build finishes, the output paths are scanned for
  references to the paths added through recursive Nix calls (in
  addition to the inputs closure). Thus, in the example above, $out
  has a reference to $hello.

The main restriction on recursive Nix calls is that they cannot do
arbitrary substitutions. For example, doing

  nix-store -r /nix/store/kmwd1hq55akdb9sc7l3finr175dajlby-hello-2.10

is forbidden unless /nix/store/kmwd... is in the inputs closure or
previously built by a recursive Nix call. This is to prevent
irreproducible derivations that have hidden dependencies on
substituters or the current store contents. Building a derivation is
fine, however, and Nix will use substitutes if available. In other
words, the builder has to present proof that it knows how to build a
desired store path from scratch by constructing a derivation graph for
that path.

Probably we should also disallow instantiating/building fixed-output
derivations (specifically, those that access the network, but
currently we have no way to mark fixed-output derivations that don't
access the network). Otherwise sandboxed derivations can bypass
sandbox restrictions and access the network.

When sandboxing is enabled, we make paths appear in the sandbox of the
builder by entering the mount namespace of the builder and
bind-mounting each path. This is tricky because we do a pivot_root()
in the builder to change the root directory of its mount namespace,
and thus the host /nix/store is not visible in the mount namespace of
the builder. To get around this, just before doing pivot_root(), we
branch a second mount namespace that shares its /nix/store mountpoint
with the parent.

Recursive Nix currently doesn't work on macOS in sandboxed mode
(because we can't change the sandbox policy of a running build) and in
non-root mode (because setns() barfs).
2019-11-06 00:52:38 +01:00
Eelco Dolstra d823381c0a
Merge branch 'fix/nix-doctor-output' of https://github.com/bhipple/nix 2019-11-05 16:04:40 +01:00
Eelco Dolstra 852554bb16
Merge branch 'nix-repl-e' of https://github.com/zimbatm/nix 2019-11-05 11:20:53 +01:00
Eelco Dolstra 1b600ecd14
Don't use SOCK_CLOEXEC on macOS
https://hydra.nixos.org/build/105428308
2019-11-05 10:25:09 +01:00
Eelco Dolstra f5a46ef0b1
Merge pull request #3202 from kraem/master
Update nix eval --help msg to not include deprecated command
2019-11-04 09:34:30 +01:00
Harald van Dijk c935ad3f02
Fix progress bar when nix-prefetch-url is piped.
The intent of the code was that if the window size cannot be determined,
it would be treated as having the maximum possible size. Because of a
missing assignment, it was actually treated as having a width of 0.

The reason the width could not be determined was because it was obtained
from stdout, not stderr, even though the printing was done to stderr.

This commit addresses both issues.
2019-11-03 21:46:59 +00:00
kraem dcd7a26063
Update nix eval --help msg to not include deprecated command 2019-11-03 18:47:28 +01:00
ng0 b811bd2172 include netinet/in.h in src/nix/main.cc
Fixes #3186
2019-11-01 14:09:42 +00:00
Eelco Dolstra 6bff1aa46d
Merge pull request #3182 from bhipple/fixup/comments
Minor updates to inline comments
2019-10-31 14:14:35 +01:00
Benjamin Hipple 80d5ec6ff4 Minor updates to inline comments
Add missing docstring on InstallableCommand. Also, some of these were wrapped
when they're right next to a line longer than the unwrapped line, so we can just
unwrap them to save vertical space.
2019-10-31 05:56:37 -04:00
Will Dietz 0e9b72e097 minor: fix mismatch of struct/class forward decl of 'Source'
Fixes the following warning and the indicate potential issue:

src/libstore/worker-protocol.hh:66:1: warning: class 'Source' was previously declared as a struct; this is valid, but may result in linker errors
under the Microsoft C++ ABI [-Wmismatched-tags]

(cherry picked from commit 6e1bb04870b1b723282d32182af286646f13bf3c)
2019-10-30 14:39:01 -05:00
Eelco Dolstra e5319a87ce
queryPathInfoUncached(): Return const ValidPathInfo 2019-10-29 13:53:04 +01:00
Eelco Dolstra 992a2ad475
Move addToStoreFromDump to Store 2019-10-29 13:38:24 +01:00
Eelco Dolstra 05819d013f
Don't create a Store in processConnection() 2019-10-29 13:36:19 +01:00
Eelco Dolstra 63b99af85a
Move Unix domain socket creation to libutil
Also drop multithread-unfriendly hacks like doing a temporary
chmod/umask.
2019-10-29 13:30:51 +01:00
Eelco Dolstra 2d37e88319
Move most of the daemon implementation to libstore 2019-10-29 13:25:33 +01:00
Eelco Dolstra 95c727caef
Remove the check against concurrent builds in the same process 2019-10-29 12:43:20 +01:00
Jonas Chevalier 9a25059656
findDerivationFilename: add FIXME 2019-10-28 21:40:02 +01:00
Jonas Chevalier d407f4d15f
nix repl: also handle lambda edit 2019-10-28 21:37:22 +01:00
Jonas Chevalier 3774fe55fd
editorFor: take a pos object instead 2019-10-28 21:36:34 +01:00
Jonas Chevalier ec448f8bb6
libexpr: findDerivationFilename return Pos instead of tuple 2019-10-28 21:29:54 +01:00
Eelco Dolstra f7ce80f90a
Factor out linkOrCopy() 2019-10-27 18:19:13 +01:00
Eelco Dolstra f1c0b2c0e1
Add O(1)-memory copyPath() function 2019-10-27 18:18:58 +01:00
Eelco Dolstra 3913afdd69
Simplification 2019-10-27 18:00:09 +01:00
Eelco Dolstra 0e459d79a6
Merge branch 'issue-3147-inNixShell-arg' of https://github.com/hercules-ci/nix 2019-10-27 17:10:19 +01:00
Robert Hensing 9d612c393a Add inNixShell = true to nix-shell auto-call
This is an alternative to the IN_NIX_SHELL environment variable,
allowing the expression to adapt itself to nix-shell without
triggering those adaptations when used as a dependency of another
shell.

Closes #3147
2019-10-27 13:16:02 +01:00
Eelco Dolstra e012384fe9
Merge branch 'tojson-tostring-fix' of https://github.com/mayflower/nix 2019-10-27 12:18:35 +01:00
Robin Gloster e583df5280
builtins.toJSON: fix __toString usage 2019-10-27 10:15:51 +01:00
Jonas Chevalier 59c7249769
libexpr: add findDerivationFilename
extract the derivation to filename:lineno heuristic
2019-10-23 17:21:16 +02:00
Jonas Chevalier 207a537343
libutil: add editorFor heuristic 2019-10-23 16:48:28 +02:00
Jonas Chevalier 73ff84f6a8
nix repl: add :edit command
This allows to have a repl-centric workflow to working on nixpkgs.

Usage:

    :edit <package> - heuristic that find the package file path

    :edit <path> - just open the editor on the file path

Once invoked, `nix repl` will open $EDITOR on that file path. Once the
editor exits, `nix repl` will automatically reload itself.
2019-10-23 16:09:42 +02:00
Eelco Dolstra 629b9b0049 Mark content-addressable paths with references as experimental 2019-10-21 18:05:31 +02:00
Eelco Dolstra e68736936a nix make-content-addressable: Add examples 2019-10-21 17:58:17 +02:00
Eelco Dolstra d77970fde7 Fix build 2019-10-21 17:49:16 +02:00
Eelco Dolstra 0abb3ad537 Allow content-addressable paths to have references
This adds a command 'nix make-content-addressable' that rewrites the
specified store paths into content-addressable paths. The advantage of
such paths is that 1) they can be imported without signatures; 2) they
can enable deduplication in cases where derivation changes do not
cause output changes (apart from store path hashes).

For example,

  $ nix make-content-addressable -r nixpkgs.cowsay
  rewrote '/nix/store/g1g31ah55xdia1jdqabv1imf6mcw0nb1-glibc-2.25-49' to '/nix/store/48jfj7bg78a8n4f2nhg269rgw1936vj4-glibc-2.25-49'
  ...
  rewrote '/nix/store/qbi6rzpk0bxjw8lw6azn2mc7ynnn455q-cowsay-3.03+dfsg1-16' to '/nix/store/iq6g2x4q62xp7y7493bibx0qn5w7xz67-cowsay-3.03+dfsg1-16'

We can then copy the resulting closure to another store without
signatures:

  $ nix copy --trusted-public-keys '' ---to ~/my-nix /nix/store/iq6g2x4q62xp7y7493bibx0qn5w7xz67-cowsay-3.03+dfsg1-16

In order to support self-references in content-addressable paths,
these paths are hashed "modulo" self-references, meaning that
self-references are zeroed out during hashing. Somewhat annoyingly,
this means that the NAR hash stored in the Nix database is no longer
necessarily equal to the output of "nix hash-path"; for
content-addressable paths, you need to pass the --modulo flag:

  $ nix path-info --json /nix/store/iq6g2x4q62xp7y7493bibx0qn5w7xz67-cowsay-3.03+dfsg1-16  | jq -r .[].narHash
  sha256:0ri611gdilz2c9rsibqhsipbfs9vwcqvs811a52i2bnkhv7w9mgw

  $ nix hash-path --type sha256 --base32 /nix/store/iq6g2x4q62xp7y7493bibx0qn5w7xz67-cowsay-3.03+dfsg1-16
  1ggznh07khq0hz6id09pqws3a8q9pn03ya3c03nwck1kwq8rclzs

  $ nix hash-path --type sha256 --base32 /nix/store/iq6g2x4q62xp7y7493bibx0qn5w7xz67-cowsay-3.03+dfsg1-16 --modulo iq6g2x4q62xp7y7493bibx0qn5w7xz67
  0ri611gdilz2c9rsibqhsipbfs9vwcqvs811a52i2bnkhv7w9mgw
2019-10-21 17:47:24 +02:00
Eelco Dolstra aabf5c86c9
Add experimental-features setting
Experimental features are now opt-in. There is currently one
experimental feature: "nix-command" (which enables the "nix"
command. This will allow us to merge experimental features more
quickly, without committing to supporting them indefinitely.

Typical usage:

$ nix build --experimental-features 'nix-command flakes' nixpkgs#hello

(cherry picked from commit 8e478c2341,
without the "flakes" feature)
2019-10-21 13:34:44 +02:00
Eelco Dolstra 389a2cebed
SourceExprCommand::getSourceExpr(): Allocate more space
Fixes #3140.
2019-10-21 13:14:39 +02:00
Eelco Dolstra 906d56a96b
ssh-ng: Don't set CPU affinity on the remote
Fixes #3138.
2019-10-11 18:49:46 +02:00
Eelco Dolstra 95cf23ee7c
nix verify: Fix uninitialized variable 2019-10-10 15:03:01 +02:00
Eelco Dolstra c3aaf3b8da
nix-env: Ignore failures creating ~/.nix-profile and ~/.nix-defexpr
https://hydra.nixos.org/build/102803093
2019-10-10 09:14:05 +02:00
Eelco Dolstra bda64a2b0f
Doh
https://hydra.nixos.org/build/102803044
2019-10-10 00:12:30 +02:00
Eelco Dolstra 20eec802ff
Force per-user group to a known value 2019-10-09 23:35:02 +02:00
Eelco Dolstra d7bae5680f
Go back to 755 permission on per-user directories
700 is pointless since the store is world-readable anyway. And
per-user/root/channels must be world-readable.
2019-10-09 23:35:02 +02:00
Eelco Dolstra c9159f86cc
nix-env: Create ~/.nix-defexpr automatically 2019-10-09 23:35:02 +02:00
Eelco Dolstra 9348f9291e
nix-env: Create ~/.nix-profile automatically 2019-10-09 23:35:01 +02:00
Eelco Dolstra 5a303093dc
Remove world-writability from per-user directories
'nix-daemon' now creates subdirectories for users when they first
connect.

Fixes #509 (CVE-2019-17365).
Should also fix #3127.
2019-10-09 23:34:48 +02:00
Eelco Dolstra 4331eeb13d
Filter ANSI escape sequences in -L output
Otherwise, builds like NixOS VM tests may leave the terminal in a
weird state and do resets.
2019-10-09 23:25:06 +02:00
Eelco Dolstra 55bba8e4f5
Make std::uncaught_exception warning less noisy 2019-10-09 23:04:11 +02:00
Eelco Dolstra 926d3e5bb0
Fix Bison 2.4 warning 2019-10-09 22:57:37 +02:00
Eelco Dolstra 99b73fb507
OCD performance fix: {find,count}+insert => insert 2019-10-09 16:06:29 +02:00