about summary refs log tree commit diff
path: root/tvix/nix-compat/src/store_path
diff options
context:
space:
mode:
authorFlorian Klink <flokli@flokli.de>2023-08-19T20·01+0200
committerflokli <flokli@flokli.de>2023-08-20T22·19+0000
commit0193f07642db752c3e14e02064c02b0fd1cc060b (patch)
tree85130551dd210f650bc66b4a1dc2d612bbaa5e0c /tvix/nix-compat/src/store_path
parent4017039595fc85c02c8c313b73073220954b9f5a (diff)
refactor(tvix/nix-compat/nixhash): validate digest lengths r/6512
There was a NixHash::new() before, which didn't perform any validation
of the digest length. We had some length validation when parsing nix
hashes or SRI hashes, but some places didn't perform validation and/or
constructed the struct directly.

Replace NixHash::new() with a
`impl TryFrom<(HashAlgo, Vec<u8>)> for NixHash`,  which does do this
validation, and update constructing code to use that, rather than
populating structs directly. In some rare cases where we're sure the
digest length is correct we still populate the struct manually.

Fixes b/291.

Change-Id: I7a323c5b18d94de0ec15e391b3e7586df42f4229
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9109
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Diffstat (limited to 'tvix/nix-compat/src/store_path')
-rw-r--r--tvix/nix-compat/src/store_path/utils.rs16
1 files changed, 14 insertions, 2 deletions
diff --git a/tvix/nix-compat/src/store_path/utils.rs b/tvix/nix-compat/src/store_path/utils.rs
index 26f6e0085c9d..201d98cce460 100644
--- a/tvix/nix-compat/src/store_path/utils.rs
+++ b/tvix/nix-compat/src/store_path/utils.rs
@@ -54,7 +54,13 @@ pub fn build_text_path<S: AsRef<str>, I: IntoIterator<Item = S>, C: AsRef<[u8]>>
                 let hasher = Sha256::new_with_prefix(content);
                 hasher.finalize()
             };
-            NixHash::new(crate::nixhash::HashAlgo::Sha256, content_digest.to_vec())
+
+            // We populate the struct directly, as we know the sha256 digest has the
+            // right size.
+            NixHash {
+                algo: crate::nixhash::HashAlgo::Sha256,
+                digest: content_digest.to_vec(),
+            }
         },
         name,
     )
@@ -100,7 +106,13 @@ pub fn build_regular_ca_path<S: AsRef<str>, I: IntoIterator<Item = S>>(
                         hasher.update(":");
                         hasher.finalize()
                     };
-                    NixHash::new(crate::nixhash::HashAlgo::Sha256, content_digest.to_vec())
+
+                    // We don't use [NixHash::from_algo_and_digest], as we know [Sha256] has
+                    // the right digest size.
+                    NixHash {
+                        algo: crate::nixhash::HashAlgo::Sha256,
+                        digest: content_digest.to_vec(),
+                    }
                 },
                 name,
             )