/
sessionmanager.go
68 lines (52 loc) · 1.3 KB
/
sessionmanager.go
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package snmp
import (
"net"
)
// A SessionManager listens on a UDP port and manages SNMP sessions.
type SessionManager struct {
sessions map[string]*Session
conn *net.UDPConn
}
// NewSessionManager creates a new SessionManager and starts
// listening on a UDP port.
func NewSessionManager() (*SessionManager, error) {
// Listen on a socket
conn, err := net.ListenUDP("udp", nil)
if err != nil {
return nil, err
}
s := &SessionManager{
sessions: map[string]*Session{},
conn: conn,
}
go s.handleDatagrams()
return s, nil
}
// handleDatagrams sends incoming datagrams to the
// corresponding sessions.
func (s *SessionManager) handleDatagrams() error {
for {
b := make([]byte, 1500)
n, addr, err := s.conn.ReadFromUDP(b)
if err != nil {
return err
}
key := addr.String()
sess, present := s.sessions[key]
if !present {
continue
}
sess.inbound <- b[:n]
}
}
// NewSession creates a new SNMP v3 session using "authPriv" mode with
// SHA authentication and AES encryption.
func (s *SessionManager) NewSession(address, user, authPassphrase, privPassphrase string) (*Session, error) {
sess, err := newSession(address, user, authPassphrase, privPassphrase)
if err != nil {
return nil, err
}
sess.conn = s.conn
s.sessions[sess.addr.String()] = sess
return sess, nil
}