Commit Graph
6 Commits
Author SHA1 Message Date
Raito Bezarius 2d0109898a libstore/build: rewire builder's environment in presence of a global CA
Historically, Nix would support copying certificate authorities inside
the sandbox so you could use them.

In addition to that, the primitives consisting of leaking environment
variables via `impureEnvVars` and `extra-sandbox-paths` to render paths
external to the sandbox visible to the builder would also constitute a
mechanism to expose special inodes which should have no influence on the
output result, e.g. interception CAs.

Unfortunately, in nixpkgs, `lib.fetchers.proxyImpureEnvVars` set
`NIX_SSL_CERT_FILE` as an impure environment variable.

A confused user may set `ssl-cert-file` via `NIX_SSL_CERT_FILE` outside the
builder believing that this will set magically the right
`NIX_SSL_CERT_FILE` inside the sandbox, but this is not true.

The combination of impure environment variables and setting `caFile`
creates a weird interaction where `NIX_SSL_CERT_FILE` points to an
"outside the builder's world" inode *AND* `ssl-cert-file` creates
this very same certificate file in /etc/ssl/certs/ca-certificates.crt
without rewriting the environment variable.

This footgun is closed by making these two features mutually
incompatible with a warning and forcibly rewriting the SSL family of
environment variables even if it was set via impure environment
variables.

Users who truly meant to use `impureEnvVars` can obtain the right
behavior by setting `ssl-cert-file` to an empty string and will have to use
`extra-sandbox-paths`.

Users who meant to use `ssl-cert-file` will have everything work
automatically with a warning hinting at nixpkgs *fixing its own bug*,
i.e. passing `NIX_SSL_CERT_FILE` as an impure environment variable and
expecting the Nix interpreter to magically reconcile the diverging
values or expecting the user to actually do the work to render the path
visible available via `extra-sandbox-paths`.

Fixes #885.

Change-Id: I32f8b5ce20fe9b6a911768114c92f95fc886cc07
Signed-off-by: Raito Bezarius <raito@lix.systems>
2025-07-27 19:42:37 +00:00
Raito Bezarius a60c1de715 Revert "libstore: don't delete already valid outputs after build"
This reverts commit e356d54d7a
because this was insufficient to fix the critical correctness bugs.

Change-Id: I91c3e368ffd13ade6a3cebbbacdb42655796ea56
2025-06-29 21:26:01 +02:00
eldritch horrors e356d54d7a libstore: don't delete already valid outputs after build
eagerly consider outputs as not needing deletion during output
registration rather than only doing so after registration. not
waiting for registration to succeed may keep store paths alive
in the file system if registration fails for some reason; that
seem preferrable to the possibility of having another instance
of this bug. since we only leave *good* outputs around there's
not much to worry about except maybe bit of wasted disk space.

fixes #883

Change-Id: I8c22c92e39b9e203f1061278f86cde19dc4474a4
2025-06-27 15:38:53 +02:00
Alois Wohlschlager cf756fdf3c libstore/build: copy ca-certificates too
In b469c6509b, the ca-certificates file was
missed. It should be copied too so that we don't end up bind-mounting a broken
symlink.

Change-Id: Ic9b292d602eb94b0e78f77f2a27a19d24665783c
2024-05-31 07:54:18 +00:00
Théophane HufschmittandK900 07b627cc6d Merge pull request #10456 from NixOS/fixpermdeniedbind
Fix adding symlink to the sandbox paths

(cherry-picked from commit da1e977bf48cff2a635034c85e7c13878e38efc2)

Change-Id: I221c85a38180800ec6552d2e86a88df48398fad8
2024-04-11 15:43:58 +03:00
John Ericson 30dcc19d1f Put functional tests in tests/functional
I think it is bad for these reasons when `tests/` contains a mix of
functional and integration tests

 - Concepts is harder to understand, the documentation makes a good
   unit vs functional vs integration distinction, but when the
   integration tests are just two subdirs within `tests/` this is not
   clear.

 - Source filtering in the `flake.nix` is more complex. We need to
   filter out some of the dirs from `tests/`, rather than simply pick
   the dirs we want and take all of them. This is a good sign the
   structure of what we are trying to do is not matching the structure
   of the files.

With this change we have a clean:
```shell-session
$ git show 'HEAD:tests'
tree HEAD:tests

functional/
installer/
nixos/
```

(cherry picked from commit 68c81c737571794f7246db53fb4774e94fcf4b7e)
2023-12-01 12:06:43 -05:00