feat: checksum pinning (#2223)

taskfile/ast/include.go

@@ -24,6 +24,7 @@ type (
 		AdvancedImport bool
 		Vars           *Vars
 		Flatten        bool
+		Checksum       string
 	}
 	// Includes is an ordered map of namespaces to includes.
 	Includes struct {
@@ -165,6 +166,7 @@ func (include *Include) UnmarshalYAML(node *yaml.Node) error {
 			Aliases  []string
 			Excludes []string
 			Vars     *Vars
+			Checksum string
 		}
 		if err := node.Decode(&includedTaskfile); err != nil {
 			return errors.NewTaskfileDecodeError(err, node)
@@ -178,6 +180,7 @@ func (include *Include) UnmarshalYAML(node *yaml.Node) error {
 		include.AdvancedImport = true
 		include.Vars = includedTaskfile.Vars
 		include.Flatten = includedTaskfile.Flatten
+		include.Checksum = includedTaskfile.Checksum
 		return nil
 	}
 
@@ -200,5 +203,7 @@ func (include *Include) DeepCopy() *Include {
 		AdvancedImport: include.AdvancedImport,
 		Vars:           include.Vars.DeepCopy(),
 		Flatten:        include.Flatten,
+		Aliases:        deepcopy.Slice(include.Aliases),
+		Checksum:       include.Checksum,
 	}
 }

taskfile/node.go

@@ -17,6 +17,8 @@ type Node interface {
 	Parent() Node
 	Location() string
 	Dir() string
+	Checksum() string
+	Verify(checksum string) bool
 	ResolveEntrypoint(entrypoint string) (string, error)
 	ResolveDir(dir string) (string, error)
 }

taskfile/node_base.go

@@ -7,8 +7,9 @@ type (
 	// designed to be embedded in other node types so that this boilerplate code
 	// does not need to be repeated.
 	baseNode struct {
-		parent Node
-		dir    string
+		parent   Node
+		dir      string
+		checksum string
 	}
 )
 
@@ -32,6 +33,12 @@ func WithParent(parent Node) NodeOption {
 	}
 }
 
+func WithChecksum(checksum string) NodeOption {
+	return func(node *baseNode) {
+		node.checksum = checksum
+	}
+}
+
 func (node *baseNode) Parent() Node {
 	return node.parent
 }
@@ -39,3 +46,11 @@ func (node *baseNode) Parent() Node {
 func (node *baseNode) Dir() string {
 	return node.dir
 }
+
+func (node *baseNode) Checksum() string {
+	return node.checksum
+}
+
+func (node *baseNode) Verify(checksum string) bool {
+	return node.checksum == "" || node.checksum == checksum
+}

taskfile/reader.go

@@ -250,6 +250,7 @@ func (r *Reader) include(ctx context.Context, node Node) error {
 				AdvancedImport: include.AdvancedImport,
 				Excludes:       include.Excludes,
 				Vars:           include.Vars,
+				Checksum:       include.Checksum,
 			}
 			if err := cache.Err(); err != nil {
 				return err
@@ -267,6 +268,7 @@ func (r *Reader) include(ctx context.Context, node Node) error {
 
 			includeNode, err := NewNode(entrypoint, include.Dir, r.insecure,
 				WithParent(node),
+				WithChecksum(include.Checksum),
 			)
 			if err != nil {
 				if include.Optional {
@@ -362,7 +364,24 @@ func (r *Reader) readNodeContent(ctx context.Context, node Node) ([]byte, error)
 	if node, isRemote := node.(RemoteNode); isRemote {
 		return r.readRemoteNodeContent(ctx, node)
 	}
-	return node.Read()
+
+	// Read the Taskfile
+	b, err := node.Read()
+	if err != nil {
+		return nil, err
+	}
+
+	// If the given checksum doesn't match the sum pinned in the Taskfile
+	checksum := checksum(b)
+	if !node.Verify(checksum) {
+		return nil, &errors.TaskfileDoesNotMatchChecksum{
+			URI:              node.Location(),
+			ExpectedChecksum: node.Checksum(),
+			ActualChecksum:   checksum,
+		}
+	}
+
+	return b, nil
 }
 
 func (r *Reader) readRemoteNodeContent(ctx context.Context, node RemoteNode) ([]byte, error) {
@@ -427,17 +446,29 @@ func (r *Reader) readRemoteNodeContent(ctx context.Context, node RemoteNode) ([]
 	}
 
 	r.debugf("found remote file at %q\n", node.Location())
-	checksum := checksum(downloadedBytes)
-	prompt := cache.ChecksumPrompt(checksum)
 
-	// Prompt the user if required
-	if prompt != "" {
-		if err := func() error {
-			r.promptMutex.Lock()
-			defer r.promptMutex.Unlock()
-			return r.promptf(prompt, node.Location())
-		}(); err != nil {
-			return nil, &errors.TaskfileNotTrustedError{URI: node.Location()}
+	// If the given checksum doesn't match the sum pinned in the Taskfile
+	checksum := checksum(downloadedBytes)
+	if !node.Verify(checksum) {
+		return nil, &errors.TaskfileDoesNotMatchChecksum{
+			URI:              node.Location(),
+			ExpectedChecksum: node.Checksum(),
+			ActualChecksum:   checksum,
+		}
+	}
+
+	// If there is no manual checksum pin, run the automatic checks
+	if node.Checksum() == "" {
+		// Prompt the user if required
+		prompt := cache.ChecksumPrompt(checksum)
+		if prompt != "" {
+			if err := func() error {
+				r.promptMutex.Lock()
+				defer r.promptMutex.Unlock()
+				return r.promptf(prompt, node.Location())
+			}(); err != nil {
+				return nil, &errors.TaskfileNotTrustedError{URI: node.Location()}
+			}
 		}
 	}