tvl-depot/tvix/store-go/pathinfo.go
Florian Klink 9118dc8a50 refactor(tvix/store): move deriver field into narinfo submessage
This information is present in the .narinfo files, it should have gone
there.

Change-Id: Ib43d0cf30c2795bf1fe77c46646174353ade0458
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9794
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: Connor Brewster <cbrewster@hey.com>
Tested-by: BuildkiteCI
2023-10-22 17:04:37 +00:00

99 lines
3.4 KiB
Go

package storev1
import (
"bytes"
"crypto/sha256"
"encoding/base64"
"fmt"
"github.com/nix-community/go-nix/pkg/storepath"
)
// Validate performs some checks on the PathInfo struct, returning either the
// StorePath of the root node, or an error.
func (p *PathInfo) Validate() (*storepath.StorePath, error) {
// ensure References has the right number of bytes.
for i, reference := range p.GetReferences() {
if len(reference) != storepath.PathHashSize {
return nil, fmt.Errorf("invalid length of digest at position %d, expected %d, got %d", i, storepath.PathHashSize, len(reference))
}
}
// If there's a Narinfo field populated..
if narInfo := p.GetNarinfo(); narInfo != nil {
// ensure the NarSha256 digest has the correct length.
if len(narInfo.GetNarSha256()) != sha256.Size {
return nil, fmt.Errorf("invalid number of bytes for NarSha256: expected %d, got %d", sha256.Size, len(narInfo.GetNarSha256()))
}
// ensure the number of references matches len(References).
if len(narInfo.GetReferenceNames()) != len(p.GetReferences()) {
return nil, fmt.Errorf("inconsistent number of references: %d (references) vs %d (narinfo)", len(narInfo.GetReferenceNames()), len(p.GetReferences()))
}
// for each ReferenceName…
for i, referenceName := range narInfo.GetReferenceNames() {
// ensure it parses to a store path
storePath, err := storepath.FromString(referenceName)
if err != nil {
return nil, fmt.Errorf("invalid ReferenceName at position %d: %w", i, err)
}
// ensure the digest matches the one at References[i]
if !bytes.Equal(p.GetReferences()[i], storePath.Digest) {
return nil, fmt.Errorf(
"digest in ReferenceName at position %d does not match digest in PathInfo, expected %s, got %s",
i,
base64.StdEncoding.EncodeToString(p.GetReferences()[i]),
base64.StdEncoding.EncodeToString(storePath.Digest),
)
}
}
// If the Deriver field is populated, ensure it parses to a StorePath.
// We can't check for it to *not* end with .drv, as the .drv files produced by
// recursive Nix end with multiple .drv suffixes, and only one is popped when
// converting to this field.
if deriver := narInfo.GetDeriver(); deriver != nil {
deriverStorePath := storepath.StorePath{
Name: string(deriver.GetName()),
Digest: deriver.GetDigest(),
}
if err := deriverStorePath.Validate(); err != nil {
return nil, fmt.Errorf("invalid deriver field: %w", err)
}
}
}
// ensure there is a (root) node present
rootNode := p.GetNode()
if rootNode == nil {
return nil, fmt.Errorf("root node must be set")
}
if err := rootNode.Validate(); err != nil {
return nil, fmt.Errorf("root node failed validation: %w", err)
}
// for all three node types, ensure the name properly parses to a store path.
// This is a stricter check as the ones already performed in the rootNode.Validate() call.
var rootNodeName []byte
if node := rootNode.GetDirectory(); node != nil {
rootNodeName = node.GetName()
} else if node := rootNode.GetFile(); node != nil {
rootNodeName = node.GetName()
} else if node := rootNode.GetSymlink(); node != nil {
rootNodeName = node.GetName()
} else {
// already caught by rootNode.Validate()
panic("unreachable")
}
storePath, err := storepath.FromString(string(rootNodeName))
if err != nil {
return nil, fmt.Errorf("unable to parse root node name %s as StorePath: %w", rootNodeName, err)
}
return storePath, nil
}