Files

274 lines
10 KiB
Go

package notifier
import (
"context"
"encoding/base64"
"encoding/json"
"errors"
"fmt"
"github.com/grafana/grafana/pkg/infra/log"
"github.com/grafana/grafana/pkg/services/ngalert/api/tooling/definitions"
"github.com/grafana/grafana/pkg/services/ngalert/notifier/channels_config"
"github.com/grafana/grafana/pkg/services/ngalert/store"
"github.com/grafana/grafana/pkg/services/secrets"
)
// Crypto allows decryption of Alertmanager Configuration and encryption of arbitrary payloads.
type Crypto interface {
LoadSecureSettings(ctx context.Context, orgId int64, receivers []*definitions.PostableApiReceiver) error
Encrypt(ctx context.Context, payload []byte, opt secrets.EncryptionOptions) ([]byte, error)
Decrypt(ctx context.Context, payload []byte) ([]byte, error)
EncryptExtraConfigs(ctx context.Context, config *definitions.PostableUserConfig) error
DecryptExtraConfigs(ctx context.Context, config *definitions.PostableUserConfig) error
getDecryptedSecret(r *definitions.PostableGrafanaReceiver, key string) (string, error)
ProcessSecureSettings(ctx context.Context, orgId int64, recvs []*definitions.PostableApiReceiver) error
}
// alertmanagerCrypto implements decryption of Alertmanager configuration and encryption of arbitrary payloads based on Grafana's encryptions.
type alertmanagerCrypto struct {
secrets secrets.Service
configs configurationStore
log log.Logger
}
func NewCrypto(secrets secrets.Service, configs configurationStore, log log.Logger) Crypto {
return &alertmanagerCrypto{
secrets: secrets,
configs: configs,
log: log,
}
}
// ProcessSecureSettings encrypts new secure settings and loads existing secure settings from the database.
func (c *alertmanagerCrypto) ProcessSecureSettings(ctx context.Context, orgId int64, recvs []*definitions.PostableApiReceiver) error {
// First, we encrypt the new or updated secure settings. Then, we load the existing secure settings from the database
// and add back any that weren't updated.
// We perform these steps in this order to ensure the hash of the secure settings remains stable when no secure
// settings were modified.
if err := EncryptReceiverConfigs(recvs, func(ctx context.Context, payload []byte) ([]byte, error) {
return c.Encrypt(ctx, payload, secrets.WithoutScope())
}); err != nil {
return fmt.Errorf("failed to encrypt receivers: %w", err)
}
if err := c.LoadSecureSettings(ctx, orgId, recvs); err != nil {
return err
}
return nil
}
// EncryptReceiverConfigs encrypts all SecureSettings in the given receivers.
func EncryptReceiverConfigs(c []*definitions.PostableApiReceiver, encrypt definitions.EncryptFn) error {
return encryptReceiverConfigs(c, encrypt, true)
}
func EncryptReceiverConfigSettings(c []*definitions.PostableApiReceiver, encrypt definitions.EncryptFn) error {
return encryptReceiverConfigs(c, encrypt, false)
}
// encryptReceiverConfigs encrypts all SecureSettings in the given receivers.
// encryptExisting determines whether to encrypt existing secure settings.
func encryptReceiverConfigs(c []*definitions.PostableApiReceiver, encrypt definitions.EncryptFn, encryptExisting bool) error {
// encrypt secure settings for storing them in DB
for _, r := range c {
switch r.Type() {
case definitions.GrafanaReceiverType:
for _, gr := range r.GrafanaManagedReceivers {
if encryptExisting {
for k, v := range gr.SecureSettings {
encryptedData, err := encrypt(context.Background(), []byte(v))
if err != nil {
return fmt.Errorf("failed to encrypt secure settings: %w", err)
}
gr.SecureSettings[k] = base64.StdEncoding.EncodeToString(encryptedData)
}
}
if len(gr.Settings) > 0 {
// We need to parse the settings to check for secret keys. If we find any, we encrypt them and
// store them in SecureSettings. This can happen from incorrect configuration or when an integration
// definition is updated to make a field secure.
settings := make(map[string]any)
if err := json.Unmarshal(gr.Settings, &settings); err != nil {
return fmt.Errorf("integration '%s' of receiver '%s' has settings that cannot be parsed as JSON: %w", gr.Type, gr.Name, err)
}
secretKeys, err := channels_config.GetSecretKeysForContactPointType(gr.Type)
if err != nil {
return fmt.Errorf("failed to get secret keys for contact point type %s: %w", gr.Type, err)
}
secureSettings := gr.SecureSettings
if secureSettings == nil {
secureSettings = make(map[string]string)
}
settingsChanged := false
secureSettingsChanged := false
for _, secretKey := range secretKeys {
settingsValue, ok := settings[secretKey]
if !ok {
continue
}
// Secrets should not be stored in settings regardless.
delete(settings, secretKey)
settingsChanged = true
// If the secret is already encrypted, we don't need to encrypt it again.
if _, ok := secureSettings[secretKey]; ok {
continue
}
if strVal, isString := settingsValue.(string); isString {
encrypted, err := encrypt(context.Background(), []byte(strVal))
if err != nil {
return fmt.Errorf("failed to encrypt secure settings: %w", err)
}
secureSettings[secretKey] = base64.StdEncoding.EncodeToString(encrypted)
secureSettingsChanged = true
}
}
// Defensive checks to limit the risk of unintentional edge case changes in this legacy API.
if settingsChanged {
// If we removed any secret keys from settings, we need to save the updated settings.
jsonBytes, err := json.Marshal(settings)
if err != nil {
return err
}
gr.Settings = jsonBytes
}
if secureSettingsChanged {
// If we added any secure settings, we need to save the updated secure settings.
gr.SecureSettings = secureSettings
}
}
}
default:
}
}
return nil
}
// LoadSecureSettings adds the corresponding unencrypted secrets stored to the list of input receivers.
func (c *alertmanagerCrypto) LoadSecureSettings(ctx context.Context, orgId int64, receivers []*definitions.PostableApiReceiver) error {
// Get the last known working configuration.
amConfig, err := c.configs.GetLatestAlertmanagerConfiguration(ctx, orgId)
if err != nil {
// If we don't have a configuration there's nothing for us to know and we should just continue saving the new one.
if !errors.Is(err, store.ErrNoAlertmanagerConfiguration) {
return fmt.Errorf("failed to get latest configuration: %w", err)
}
}
currentReceiverMap := make(map[string]*definitions.PostableGrafanaReceiver)
if amConfig != nil {
currentConfig, err := Load([]byte(amConfig.AlertmanagerConfiguration))
// If the current config is un-loadable, treat it as if it never existed. Providing a new, valid config should be able to "fix" this state.
if err != nil {
c.log.Warn("Last known alertmanager configuration was invalid. Overwriting...")
} else {
// First we encrypt the secure settings in the existing configuration.
// This is done to ensure that any secure settings incorrectly stored in Settings are encrypted and moved to
// SecureSettings. This can happen if an integration definition is updated to make a field secure.
if err := EncryptReceiverConfigSettings(currentConfig.AlertmanagerConfig.Receivers, func(ctx context.Context, payload []byte) ([]byte, error) {
return c.Encrypt(ctx, payload, secrets.WithoutScope())
}); err != nil {
return fmt.Errorf("failed to encrypt receivers: %w", err)
}
currentReceiverMap = currentConfig.GetGrafanaReceiverMap()
}
}
// Copy the previously known secure settings.
for i, r := range receivers {
for j, gr := range r.GrafanaManagedReceivers {
if gr.UID == "" { // new receiver
continue
}
cgmr, ok := currentReceiverMap[gr.UID]
if !ok {
// It tries to update a receiver that didn't previously exist
return UnknownReceiverError{UID: gr.UID}
}
// Frontend sends only the secure settings that have to be updated
// Therefore we have to copy from the last configuration only those secure settings not included in the request
for key, encryptedValue := range cgmr.SecureSettings {
_, ok := gr.SecureSettings[key]
if !ok {
if receivers[i].PostableGrafanaReceivers.GrafanaManagedReceivers[j].SecureSettings == nil {
receivers[i].PostableGrafanaReceivers.GrafanaManagedReceivers[j].SecureSettings = make(map[string]string, len(cgmr.SecureSettings))
}
receivers[i].PostableGrafanaReceivers.GrafanaManagedReceivers[j].SecureSettings[key] = encryptedValue
}
}
}
}
return nil
}
func (c *alertmanagerCrypto) getDecryptedSecret(r *definitions.PostableGrafanaReceiver, key string) (string, error) {
storedValue, ok := r.SecureSettings[key]
if !ok {
return "", nil
}
decodeValue, err := base64.StdEncoding.DecodeString(storedValue)
if err != nil {
return "", err
}
decryptedValue, err := c.secrets.Decrypt(context.Background(), decodeValue)
if err != nil {
return "", err
}
return string(decryptedValue), nil
}
// Encrypt delegates encryption to secrets.Service.
func (c *alertmanagerCrypto) Encrypt(ctx context.Context, payload []byte, opt secrets.EncryptionOptions) ([]byte, error) {
return c.secrets.Encrypt(ctx, payload, opt)
}
func (c *alertmanagerCrypto) Decrypt(ctx context.Context, payload []byte) ([]byte, error) {
return c.secrets.Decrypt(ctx, payload)
}
func (c *alertmanagerCrypto) EncryptExtraConfigs(ctx context.Context, config *definitions.PostableUserConfig) error {
for i := range config.ExtraConfigs {
encryptedValue, err := c.secrets.Encrypt(ctx, []byte(config.ExtraConfigs[i].AlertmanagerConfig), secrets.WithoutScope())
if err != nil {
return fmt.Errorf("failed to encrypt extra configuration: %w", err)
}
config.ExtraConfigs[i].AlertmanagerConfig = base64.StdEncoding.EncodeToString(encryptedValue)
}
return nil
}
func (c *alertmanagerCrypto) DecryptExtraConfigs(ctx context.Context, config *definitions.PostableUserConfig) error {
for i := range config.ExtraConfigs {
encryptedValue, err := base64.StdEncoding.DecodeString(config.ExtraConfigs[i].AlertmanagerConfig)
if err != nil {
return fmt.Errorf("failed to base64 decode extra configuration: %w", err)
}
decryptedValue, err := c.secrets.Decrypt(ctx, encryptedValue)
if err != nil {
return fmt.Errorf("failed to decrypt extra configuration: %w", err)
}
config.ExtraConfigs[i].AlertmanagerConfig = string(decryptedValue)
}
return nil
}