| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package ntpd |
| 4 | |
| 5 | import ( |
| 6 | "net" |
| 7 | "time" |
| 8 | |
| 9 | "github.com/facebook/time/ntp/control" |
| 10 | ) |
| 11 | |
| 12 | type ntpConn interface { |
| 13 | systemInfo() (map[string]string, error) |
| 14 | peerInfo(id uint16) (map[string]string, error) |
| 15 | peerIDs() ([]uint16, error) |
| 16 | close() |
| 17 | } |
| 18 | |
| 19 | func newNTPClient(c Config) (ntpConn, error) { |
| 20 | conn, err := net.DialTimeout("udp", c.Address, c.Timeout.Duration()) |
| 21 | if err != nil { |
| 22 | return nil, err |
| 23 | } |
| 24 | |
| 25 | client := &ntpClient{ |
| 26 | conn: conn, |
| 27 | timeout: c.Timeout.Duration(), |
| 28 | client: &control.NTPClient{Connection: conn}, |
| 29 | } |
| 30 | |
| 31 | return client, nil |
| 32 | } |
| 33 | |
| 34 | type ntpClient struct { |
| 35 | conn net.Conn |
| 36 | timeout time.Duration |
| 37 | client *control.NTPClient |
| 38 | } |
| 39 | |
| 40 | func (c *ntpClient) systemInfo() (map[string]string, error) { |
| 41 | return c.peerInfo(0) |
| 42 | } |
| 43 | |
| 44 | func (c *ntpClient) peerInfo(id uint16) (map[string]string, error) { |
| 45 | msg := &control.NTPControlMsgHead{ |
| 46 | VnMode: control.MakeVnMode(2, control.Mode), |
| 47 | REMOp: control.OpReadVariables, |
| 48 | AssociationID: id, |
| 49 | } |
| 50 | |
| 51 | if err := c.conn.SetDeadline(time.Now().Add(c.timeout)); err != nil { |
| 52 | return nil, err |
| 53 | } |
| 54 | |
| 55 | resp, err := c.client.Communicate(msg) |
| 56 | if err != nil { |
| 57 | return nil, err |
| 58 | } |
| 59 | |
| 60 | return resp.GetAssociationInfo() |
| 61 | } |
| 62 | |
| 63 | func (c *ntpClient) peerIDs() ([]uint16, error) { |
| 64 | msg := &control.NTPControlMsgHead{ |
| 65 | VnMode: control.MakeVnMode(2, control.Mode), |
| 66 | REMOp: control.OpReadStatus, |
| 67 | } |
| 68 | |
| 69 | if err := c.conn.SetDeadline(time.Now().Add(c.timeout)); err != nil { |
| 70 | return nil, err |
| 71 | } |
| 72 | |
| 73 | resp, err := c.client.Communicate(msg) |
| 74 | if err != nil { |
| 75 | return nil, err |
| 76 | } |
| 77 | |
| 78 | peers, err := resp.GetAssociations() |
| 79 | if err != nil { |
| 80 | return nil, err |
| 81 | } |
| 82 | |
| 83 | var ids []uint16 |
| 84 | for id := range peers { |
| 85 | ids = append(ids, id) |
| 86 | } |
| 87 | |
| 88 | return ids, nil |
| 89 | } |
| 90 | |
| 91 | func (c *ntpClient) close() { |
| 92 | if c.conn != nil { |
| 93 | _ = c.conn.Close() |
| 94 | c.conn = nil |
| 95 | } |
| 96 | } |