Enforce and document file hash requirement for MCPB packages (#368)

## Summary
Implements mandatory file hash validation for MCPB (MCP Bundle) packages
to ensure file integrity and security.

## Changes
- **Validator enforcement**: MCPB packages now require `file_sha256`
field at publish time
- **Test coverage**: Updated all MCPB test cases to include valid
SHA-256 hashes
- **Documentation**: Updated publisher guide and schema to reflect hash
requirement
- **Error handling**: Clear error message when hash is missing

## Security Impact
This ensures the complete security workflow for MCPB packages:
1. Authors generate and provide SHA-256 hashes when publishing
2. Registry validates hash is present (but doesn't verify content)
3. MCP clients validate hash matches downloaded file before installation

Fixes #351
This commit is contained in:
adam jones 2025-09-08 11:38:25 -07:00 • committed by GitHub
commit 8f5e17d0fe
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
3 changed files with 72 additions and 24 deletions

View file

@ -13,6 +13,11 @@ import (
)
func ValidateMCPB(ctx context.Context, pkg model.Package, _ string) error {
// MCPB packages must include a file hash for integrity verification
if pkg.FileSHA256 == "" {
return fmt.Errorf("MCPB package must include a file_sha256 hash for integrity verification")
}
err := validateMCPBUrl(pkg.Identifier)
if err != nil {
return err

View file

@ -16,6 +16,7 @@ func TestValidateMCPB(t *testing.T) {
name string
packageName string
serverName string
fileSHA256 string
expectError bool
errorMessage string
}{
@ -23,18 +24,29 @@ func TestValidateMCPB(t *testing.T) {
name: "valid MCPB package should pass",
packageName: "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb",
serverName: "io.github.domdomegg/airtable-mcp-server",
fileSHA256: "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce",
expectError: false,
},
{
name: "valid MCPB package should pass",
packageName: "https://github.com/microsoft/playwright-mcp/releases/download/v0.0.36/playwright-mcp-extension-v0.0.36.zip",
serverName: "com.microsoft/playwright-mcp",
fileSHA256: "abc123ef4567890abcdef1234567890abcdef1234567890abcdef1234567890",
expectError: false,
},
{
name: "valid MCPB package with .mcpb extension should fail accessibility check",
name: "MCPB package without file hash should fail",
packageName: "https://github.com/example/server/releases/download/v1.0.0/server.mcpb",
serverName: "com.example/test",
fileSHA256: "",
expectError: true,
errorMessage: "must include a file_sha256 hash for integrity verification",
},
{
name: "non-existent .mcpb package should fail accessibility check",
packageName: "https://github.com/example/server/releases/download/v1.0.0/server.mcpb",
serverName: "com.example/test",
fileSHA256: "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce",
expectError: true,
errorMessage: "not publicly accessible",
},
@ -42,6 +54,7 @@ func TestValidateMCPB(t *testing.T) {
name: "invalid URL without mcp anywhere should fail",
packageName: "https://github.com/example/server/releases/download/v1.0.0/server.tar.gz",
serverName: "com.example/test",
fileSHA256: "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce",
expectError: true,
errorMessage: "URL must contain 'mcp'",
},
@ -49,6 +62,7 @@ func TestValidateMCPB(t *testing.T) {
name: "invalid URL format should fail",
packageName: "not://a valid url for mcpb!",
serverName: "com.example/test",
fileSHA256: "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce",
expectError: true,
errorMessage: "invalid MCPB package URL",
},
@ -56,6 +70,7 @@ func TestValidateMCPB(t *testing.T) {
name: "non-existent file should fail accessibility check",
packageName: "https://github.com/nonexistent/repo/releases/download/v1.0.0/mcp-server.tar.gz",
serverName: "com.example/test",
fileSHA256: "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce",
expectError: true,
errorMessage: "not publicly accessible",
},
@ -66,6 +81,7 @@ func TestValidateMCPB(t *testing.T) {
pkg := model.Package{
RegistryType: model.RegistryTypeMCPB,
Identifier: tt.packageName,
FileSHA256: tt.fileSHA256,
}
err := registries.ValidateMCPB(ctx, pkg, tt.serverName)

View file

@ -1189,33 +1189,37 @@ func TestValidate_RegistryTypesAndUrls(t *testing.T) {
baseURL string
identifier string
version string
fileSHA256 string
expectError bool
}{
// Valid registry types (should pass)
{"valid_npm", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeNPM, model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", false},
{"valid_npm", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeNPM, "", "airtable-mcp-server", "1.7.2", false},
{"valid_pypi", "io.github.domdomegg/time-mcp-pypi", model.RegistryTypePyPI, model.RegistryURLPyPI, "time-mcp-pypi", "1.0.1", false},
{"valid_pypi", "io.github.domdomegg/time-mcp-pypi", model.RegistryTypePyPI, "", "time-mcp-pypi", "1.0.1", false},
{"valid_oci", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeOCI, model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", false},
{"valid_nuget", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", false},
{"valid_nuget", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, "", "TimeMcpServer", "1.0.2", false},
{"valid_mcpb_github", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeMCPB, model.RegistryURLGitHub, "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", false},
{"valid_mcpb_github", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeMCPB, "", "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", false},
{"valid_mcpb_gitlab", "io.gitlab.fforster/gitlab-mcp", model.RegistryTypeMCPB, model.RegistryURLGitLab, "https://gitlab.com/fforster/gitlab-mcp/-/releases/v1.31.0/downloads/gitlab-mcp_1.31.0_Linux_x86_64.tar.gz", "1.31.0", false}, // this is not actually a valid mcpb, but it's the closest I can get for testing for now
{"valid_mcpb_gitlab", "io.gitlab.fforster/gitlab-mcp", model.RegistryTypeMCPB, "", "https://gitlab.com/fforster/gitlab-mcp/-/releases/v1.31.0/downloads/gitlab-mcp_1.31.0_Linux_x86_64.tar.gz", "1.31.0", false}, // this is not actually a valid mcpb, but it's the closest I can get for testing for now
{"valid_npm", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeNPM, model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", "", false},
{"valid_npm", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeNPM, "", "airtable-mcp-server", "1.7.2", "", false},
{"valid_pypi", "io.github.domdomegg/time-mcp-pypi", model.RegistryTypePyPI, model.RegistryURLPyPI, "time-mcp-pypi", "1.0.1", "", false},
{"valid_pypi", "io.github.domdomegg/time-mcp-pypi", model.RegistryTypePyPI, "", "time-mcp-pypi", "1.0.1", "", false},
{"valid_oci", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeOCI, model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", "", false},
{"valid_nuget", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", "", false},
{"valid_nuget", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, "", "TimeMcpServer", "1.0.2", "", false},
{"valid_mcpb_github", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeMCPB, model.RegistryURLGitHub, "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce", false},
{"valid_mcpb_github", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeMCPB, "", "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", "fe333e598595000ae021bd27117db32ec69af6987f507ba7a63c90638ff633ce", false},
{"valid_mcpb_gitlab", "io.gitlab.fforster/gitlab-mcp", model.RegistryTypeMCPB, model.RegistryURLGitLab, "https://gitlab.com/fforster/gitlab-mcp/-/releases/v1.31.0/downloads/gitlab-mcp_1.31.0_Linux_x86_64.tar.gz", "1.31.0", "abc123ef4567890abcdef1234567890abcdef1234567890abcdef1234567890", false}, // this is not actually a valid mcpb, but it's the closest I can get for testing for now
{"valid_mcpb_gitlab", "io.gitlab.fforster/gitlab-mcp", model.RegistryTypeMCPB, "", "https://gitlab.com/fforster/gitlab-mcp/-/releases/v1.31.0/downloads/gitlab-mcp_1.31.0_Linux_x86_64.tar.gz", "1.31.0", "abc123ef4567890abcdef1234567890abcdef1234567890abcdef1234567890", false}, // this is not actually a valid mcpb, but it's the closest I can get for testing for now
// Test MCPB without file hash (should fail)
{"invalid_mcpb_no_hash", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeMCPB, model.RegistryURLGitHub, "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", "", true},
// Invalid registry types (should fail)
{"invalid_maven", "io.github.domdomegg/airtable-mcp-server", "maven", model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", true},
{"invalid_cargo", "io.github.domdomegg/time-mcp-pypi", "cargo", model.RegistryURLPyPI, "time-mcp-pypi", "1.0.1", true},
{"invalid_gem", "io.github.domdomegg/airtable-mcp-server", "gem", model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", true},
{"invalid_unknown", "io.github.domdomegg/time-mcp-server", "unknown", model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", true},
{"invalid_blank", "io.github.domdomegg/time-mcp-server", "", model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", true},
{"invalid_docker", "io.github.domdomegg/airtable-mcp-server", "docker", model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", true}, // should be oci
{"invalid_github", "io.github.domdomegg/airtable-mcp-server", "github", model.RegistryURLGitHub, "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", true}, // should be mcpb
{"invalid_maven", "io.github.domdomegg/airtable-mcp-server", "maven", model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", "", true},
{"invalid_cargo", "io.github.domdomegg/time-mcp-pypi", "cargo", model.RegistryURLPyPI, "time-mcp-pypi", "1.0.1", "", true},
{"invalid_gem", "io.github.domdomegg/airtable-mcp-server", "gem", model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", "", true},
{"invalid_unknown", "io.github.domdomegg/time-mcp-server", "unknown", model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", "", true},
{"invalid_blank", "io.github.domdomegg/time-mcp-server", "", model.RegistryURLNuGet, "TimeMcpServer", "1.0.2", "", true},
{"invalid_docker", "io.github.domdomegg/airtable-mcp-server", "docker", model.RegistryURLDocker, "domdomegg/airtable-mcp-server", "1.7.2", "", true}, // should be oci
{"invalid_github", "io.github.domdomegg/airtable-mcp-server", "github", model.RegistryURLGitHub, "https://github.com/domdomegg/airtable-mcp-server/releases/download/v1.7.2/airtable-mcp-server.mcpb", "1.7.2", "", true}, // should be mcpb
{"invalid_mix_1", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, model.RegistryURLNPM, "TimeMcpServer", "1.0.2", true},
{"invalid_mix_2", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeOCI, model.RegistryURLNPM, "domdomegg/airtable-mcp-server", "1.7.2", true},
{"invalid_mix_3", "io.github.domdomegg/airtable-mcp-server", model.RegistryURLNPM, model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", true},
{"invalid_mix_1", "io.github.domdomegg/time-mcp-server", model.RegistryTypeNuGet, model.RegistryURLNPM, "TimeMcpServer", "1.0.2", "", true},
{"invalid_mix_2", "io.github.domdomegg/airtable-mcp-server", model.RegistryTypeOCI, model.RegistryURLNPM, "domdomegg/airtable-mcp-server", "1.7.2", "", true},
{"invalid_mix_3", "io.github.domdomegg/airtable-mcp-server", model.RegistryURLNPM, model.RegistryURLNPM, "airtable-mcp-server", "1.7.2", "", true},
}
for _, tc := range testCases {
@ -1237,6 +1241,7 @@ func TestValidate_RegistryTypesAndUrls(t *testing.T) {
RegistryType: tc.registryType,
RegistryBaseURL: tc.baseURL,
Version: tc.version,
FileSHA256: tc.fileSHA256,
Transport: model.Transport{
Type: "stdio",
},