open-consul/agent/consul/acl_client.go
Matt Keeler 141eb60f06
Add per-agent reconnect timeouts (#8781)
This allows for client agent to be run in a more stateless manner where they may be abruptly terminated and not expected to come back. If advertising a per-agent reconnect timeout using the advertise_reconnect_timeout configuration when that agent leaves, other agents will wait only that amount of time for the agent to come back before reaping it.

This has the advantageous side effect of causing servers to deregister the node/services/checks for that agent sooner than if the global reconnect_timeout was used.
2020-10-08 15:02:19 -04:00

128 lines
4 KiB
Go

package consul
import (
"sync/atomic"
"time"
"github.com/hashicorp/consul/acl"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/lib/serf"
)
var clientACLCacheConfig *structs.ACLCachesConfig = &structs.ACLCachesConfig{
// The ACL cache configuration on client agents is more conservative than
// on the servers. It is assumed that individual client agents will have
// fewer distinct identities accessing the client than a server would
// and thus can put smaller limits on the amount of ACL caching done.
//
// Identities - number of identities/acl tokens that can be cached
Identities: 1024,
// Policies - number of unparsed ACL policies that can be cached
Policies: 128,
// ParsedPolicies - number of parsed ACL policies that can be cached
ParsedPolicies: 128,
// Authorizers - number of compiled multi-policy effective policies that can be cached
Authorizers: 256,
// Roles - number of ACL roles that can be cached
Roles: 128,
}
func (c *Client) UseLegacyACLs() bool {
return atomic.LoadInt32(&c.useNewACLs) == 0
}
func (c *Client) monitorACLMode() {
waitTime := aclModeCheckMinInterval
for {
foundServers, mode, _ := ServersGetACLMode(c, "", c.config.Datacenter)
if foundServers && mode == structs.ACLModeEnabled {
c.logger.Debug("transitioned out of legacy ACL mode")
c.updateSerfTags("acls", string(structs.ACLModeEnabled))
atomic.StoreInt32(&c.useNewACLs, 1)
return
}
select {
case <-c.shutdownCh:
return
case <-time.After(waitTime):
// do nothing
}
// calculate the amount of time to wait for the next round
waitTime = waitTime * 2
if waitTime > aclModeCheckMaxInterval {
waitTime = aclModeCheckMaxInterval
}
}
}
func (c *Client) ACLDatacenter(legacy bool) string {
// For resolution running on clients, when not in
// legacy mode the servers within the current datacenter
// must be queried first to pick up local tokens. When
// in legacy mode the clients should directly query the
// ACL Datacenter. When no ACL datacenter has been set
// then we assume that the local DC is the ACL DC
if legacy && c.config.ACLDatacenter != "" {
return c.config.ACLDatacenter
}
return c.config.Datacenter
}
func (c *Client) ResolveIdentityFromToken(token string) (bool, structs.ACLIdentity, error) {
// clients do no local identity resolution at the moment
return false, nil, nil
}
func (c *Client) ResolvePolicyFromID(policyID string) (bool, *structs.ACLPolicy, error) {
// clients do no local policy resolution at the moment
return false, nil, nil
}
func (c *Client) ResolveRoleFromID(roleID string) (bool, *structs.ACLRole, error) {
// clients do no local role resolution at the moment
return false, nil, nil
}
func (c *Client) ResolveToken(token string) (acl.Authorizer, error) {
return c.acls.ResolveToken(token)
}
func (c *Client) ResolveTokenToIdentity(token string) (structs.ACLIdentity, error) {
// not using ResolveTokenToIdentityAndAuthorizer because in this case we don't
// need to resolve the roles, policies and namespace but just want the identity
// information such as accessor id.
return c.acls.ResolveTokenToIdentity(token)
}
func (c *Client) ResolveTokenToIdentityAndAuthorizer(token string) (structs.ACLIdentity, acl.Authorizer, error) {
return c.acls.ResolveTokenToIdentityAndAuthorizer(token)
}
func (c *Client) ResolveTokenAndDefaultMeta(token string, entMeta *structs.EnterpriseMeta, authzContext *acl.AuthorizerContext) (acl.Authorizer, error) {
identity, authz, err := c.acls.ResolveTokenToIdentityAndAuthorizer(token)
if err != nil {
return nil, err
}
// Default the EnterpriseMeta based on the Tokens meta or actual defaults
// in the case of unknown identity
if identity != nil {
entMeta.Merge(identity.EnterpriseMetadata())
} else {
entMeta.Merge(structs.DefaultEnterpriseMeta())
}
// Use the meta to fill in the ACL authorization context
entMeta.FillAuthzContext(authzContext)
return authz, err
}
func (c *Client) updateSerfTags(key, value string) {
// Update the LAN serf
serf.UpdateTag(c.serf, key, value)
}