configmap.go

/*
Copyright IBM Corp. 2017 All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

                 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package configtx

import (
	"fmt"
	"strings"

	cb "github.com/hyperledger/fabric/protos/common"

	"github.com/golang/protobuf/proto"
)

const (
	GroupPrefix  = "[Groups] "
	ValuePrefix  = "[Values] "
	PolicyPrefix = "[Policy] " // The plurarility doesn't match, but, it makes the logs much easier being the same length as "Groups" and "Values"

	PathSeparator = "/"

	// Hacky fix constants, used in recurseConfigMap
	hackyFixOrdererCapabilities = "[Values] /Channel/Orderer/Capabilities"
	hackyFixNewModPolicy        = "Admins"
)

// MapConfig is intended to be called outside this file
// it takes a ConfigGroup and generates a map of fqPath to comparables (or error on invalid keys)
func MapConfig(channelGroup *cb.ConfigGroup, rootGroupKey string) (map[string]comparable, error) {
	result := make(map[string]comparable)
	if channelGroup != nil {
		err := recurseConfig(result, []string{rootGroupKey}, channelGroup)
		if err != nil {
			return nil, err
		}
	}
	return result, nil
}

// addToMap is used only internally by MapConfig
func addToMap(cg comparable, result map[string]comparable) error {
	var fqPath string

	switch {
	case cg.ConfigGroup != nil:
		fqPath = GroupPrefix
	case cg.ConfigValue != nil:
		fqPath = ValuePrefix
	case cg.ConfigPolicy != nil:
		fqPath = PolicyPrefix
	}

	if err := validateConfigID(cg.key); err != nil {
		return fmt.Errorf("Illegal characters in key: %s", fqPath)
	}

	if len(cg.path) == 0 {
		fqPath += PathSeparator + cg.key
	} else {
		fqPath += PathSeparator + strings.Join(cg.path, PathSeparator) + PathSeparator + cg.key
	}

	logger.Debugf("Adding to config map: %s", fqPath)

	result[fqPath] = cg

	return nil
}

// recurseConfig is used only internally by MapConfig
func recurseConfig(result map[string]comparable, path []string, group *cb.ConfigGroup) error {
	if err := addToMap(comparable{key: path[len(path)-1], path: path[:len(path)-1], ConfigGroup: group}, result); err != nil {
		return err
	}

	for key, group := range group.Groups {
		nextPath := make([]string, len(path)+1)
		copy(nextPath, path)
		nextPath[len(nextPath)-1] = key
		if err := recurseConfig(result, nextPath, group); err != nil {
			return err
		}
	}

	for key, value := range group.Values {
		if err := addToMap(comparable{key: key, path: path, ConfigValue: value}, result); err != nil {
			return err
		}
	}

	for key, policy := range group.Policies {
		if err := addToMap(comparable{key: key, path: path, ConfigPolicy: policy}, result); err != nil {
			return err
		}
	}

	return nil
}

// configMapToConfig is intended to be called from outside this file
// It takes a configMap and converts it back into a *cb.ConfigGroup structure
func configMapToConfig(configMap map[string]comparable, rootGroupKey string) (*cb.ConfigGroup, error) {
	rootPath := PathSeparator + rootGroupKey
	return recurseConfigMap(rootPath, configMap)
}

// recurseConfigMap is used only internally by configMapToConfig
// Note, this function no longer mutates the cb.Config* entries within configMap
func recurseConfigMap(path string, configMap map[string]comparable) (*cb.ConfigGroup, error) {
	groupPath := GroupPrefix + path
	group, ok := configMap[groupPath]
	if !ok {
		return nil, fmt.Errorf("Missing group at path: %s", groupPath)
	}

	if group.ConfigGroup == nil {
		return nil, fmt.Errorf("ConfigGroup not found at group path: %s", groupPath)
	}

	newConfigGroup := cb.NewConfigGroup()
	proto.Merge(newConfigGroup, group.ConfigGroup)

	for key, _ := range group.Groups {
		updatedGroup, err := recurseConfigMap(path+PathSeparator+key, configMap)
		if err != nil {
			return nil, err
		}
		newConfigGroup.Groups[key] = updatedGroup
	}

	for key, _ := range group.Values {
		valuePath := ValuePrefix + path + PathSeparator + key
		value, ok := configMap[valuePath]
		if !ok {
			return nil, fmt.Errorf("Missing value at path: %s", valuePath)
		}
		if value.ConfigValue == nil {
			return nil, fmt.Errorf("ConfigValue not found at value path: %s", valuePath)
		}
		newConfigGroup.Values[key] = proto.Clone(value.ConfigValue).(*cb.ConfigValue)
	}

	for key, _ := range group.Policies {
		policyPath := PolicyPrefix + path + PathSeparator + key
		policy, ok := configMap[policyPath]
		if !ok {
			return nil, fmt.Errorf("Missing policy at path: %s", policyPath)
		}
		if policy.ConfigPolicy == nil {
			return nil, fmt.Errorf("ConfigPolicy not found at policy path: %s", policyPath)
		}
		newConfigGroup.Policies[key] = proto.Clone(policy.ConfigPolicy).(*cb.ConfigPolicy)
		logger.Debugf("Setting policy for key %s to %+v", key, group.Policies[key])
	}

	// This is a really very hacky fix to facilitate upgrading channels which were constructed
	// using the channel generation from v1.0 with bugs FAB-5309, and FAB-6080.
	// In summary, these channels were constructed with a bug which left mod_policy unset in some cases.
	// If mod_policy is unset, it's impossible to modify the element, and current code disallows
	// unset mod_policy values.  This hack 'fixes' existing config with empty mod_policy values.
	// If the capabilities framework is on, it sets any unset mod_policy to 'Admins'.
	// This code needs to sit here until validation of v1.0 chains is deprecated from the codebase.
	if _, ok := configMap[hackyFixOrdererCapabilities]; ok {
		// Hacky fix constants, used in recurseConfigMap
		if newConfigGroup.ModPolicy == "" {
			logger.Debugf("Performing upgrade of group %s empty mod_policy", groupPath)
			newConfigGroup.ModPolicy = hackyFixNewModPolicy
		}

		for key, value := range newConfigGroup.Values {
			if value.ModPolicy == "" {
				logger.Debugf("Performing upgrade of value %s empty mod_policy", ValuePrefix+path+PathSeparator+key)
				value.ModPolicy = hackyFixNewModPolicy
			}
		}

		for key, policy := range newConfigGroup.Policies {
			if policy.ModPolicy == "" {
				logger.Debugf("Performing upgrade of policy %s empty mod_policy", PolicyPrefix+path+PathSeparator+key)

				policy.ModPolicy = hackyFixNewModPolicy
			}
		}
	}

	return newConfigGroup, nil
}