diff options
Diffstat (limited to 'lib/udp.c')
| -rw-r--r-- | lib/udp.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/lib/udp.c b/lib/udp.c new file mode 100644 index 0000000..911616d --- /dev/null +++ b/lib/udp.c @@ -0,0 +1,179 @@ +/* Copyright 2011 NORDUnet A/S. All rights reserved. + See the file COPYING for licensing information. */ + +#if defined HAVE_CONFIG_H +#include <config.h> +#endif + +#include <assert.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <event2/event.h> +#include <radsec/radsec.h> +#include <radsec/radsec-impl.h> +#include "debug.h" +#include "event.h" +#include "compat.h" +#include "udp.h" + +/* Send one packet, the first in queue. */ +static int +_send (struct rs_connection *conn, int fd) +{ + ssize_t r = 0; + struct rs_packet *pkt = conn->out_queue; + + assert (pkt->rpkt); + assert (pkt->rpkt->data); + + /* Send. */ + r = compat_send (fd, pkt->rpkt->data, pkt->rpkt->data_len, 0); + if (r == -1) + { + int sockerr = evutil_socket_geterror (pkt->conn->fd); + if (sockerr != EAGAIN) + return rs_err_conn_push_fl (pkt->conn, RSE_SOCKERR, __FILE__, __LINE__, + "%d: send: %d (%s)", fd, sockerr, + evutil_socket_error_to_string (sockerr)); + } + + assert (r == pkt->rpkt->data_len); + /* Unlink the packet. */ + conn->out_queue = pkt->next; + + /* If there are more packets in queue, add the write event again. */ + if (pkt->conn->out_queue) + { + r = event_add (pkt->conn->wev, NULL); + if (r < 0) + return rs_err_conn_push_fl (pkt->conn, RSE_EVENT, __FILE__, __LINE__, + "event_add: %s", evutil_gai_strerror (r)); + rs_debug (("%s: re-adding the write event\n", __func__)); + } + + return RSE_OK; +} + +/* Callback for conn->wev and conn->rev. FIXME: Rename. + + USER_DATA contains connection for EV_READ and a packet for + EV_WRITE. This is because we don't have a connect/establish entry + point at the user level -- send implies connect so when we're + connected we need the packet to send. */ +static void +_evcb (evutil_socket_t fd, short what, void *user_data) +{ + rs_debug (("%s: fd=%d what =", __func__, fd)); + if (what & EV_TIMEOUT) rs_debug ((" TIMEOUT")); + if (what & EV_READ) rs_debug ((" READ")); + if (what & EV_WRITE) rs_debug ((" WRITE")); + rs_debug (("\n")); + + if (what & EV_READ) + { + /* Read a single UDP packet and stick it in USER_DATA. */ + /* TODO: Verify that unsolicited packets are dropped. */ + struct rs_packet *pkt = (struct rs_packet *) user_data; + ssize_t r = 0; + + assert (pkt); + assert (pkt->conn); + + pkt->rpkt->data = rs_malloc (pkt->conn->ctx, 4096); + if (pkt->rpkt->data == NULL) + { + rs_err_conn_push_fl (pkt->conn, RSE_NOMEM, __FILE__, __LINE__, NULL); + return; + } + r = compat_recv (fd, pkt->rpkt->data, 4096, MSG_TRUNC); + if (r == -1) + { + int sockerr = evutil_socket_geterror (pkt->conn->fd); + if (sockerr == EAGAIN) + { + /* FIXME: Really shouldn't happen since we've been told + that fd is readable! */ + rs_debug (("%s: EAGAIN reading UDP packet -- wot?")); + return; + } + + /* Hard error. */ + rs_err_conn_push_fl (pkt->conn, RSE_SOCKERR, __FILE__, __LINE__, + "%d: recv: %d (%s)", fd, sockerr, + evutil_socket_error_to_string (sockerr)); + event_del (pkt->conn->tev); + return; + } + event_del (pkt->conn->tev); + if (r < 20 || r > 4096) /* Short or long packet. */ + { + rs_err_conn_push (pkt->conn, RSE_INVALID_PKT, + "invalid packet length: %d", + pkt->rpkt->data_len); + return; + } + pkt->rpkt->data_len = (pkt->rpkt->data[2] << 8) + pkt->rpkt->data[3]; + if (!rad_packet_ok (pkt->rpkt, 0)) + { + rs_err_conn_push_fl (pkt->conn, RSE_FR, __FILE__, __LINE__, + "invalid packet: %s", fr_strerror ()); + return; + } + /* Hand over message to user. This changes ownership of pkt. + Don't touch it afterwards -- it might have been freed. */ + if (pkt->conn->callbacks.received_cb) + pkt->conn->callbacks.received_cb (pkt, pkt->conn->user_data); + } + else if (what & EV_WRITE) + { + struct rs_packet *pkt = (struct rs_packet *) user_data; + assert (pkt); + assert (pkt->conn); + + if (!pkt->conn->is_connected) + event_on_connect (pkt->conn, pkt); + + if (pkt->conn->out_queue) + if (_send (pkt->conn, fd) == RSE_OK) + if (pkt->conn->callbacks.sent_cb) + pkt->conn->callbacks.sent_cb (pkt->conn->user_data); + } + +#if defined (DEBUG) + if (what & EV_TIMEOUT) + rs_debug (("%s: timeout on UDP event, shouldn't happen\n", __func__)); +#endif +} + +int +udp_init (struct rs_connection *conn, struct rs_packet *pkt) +{ + assert (!conn->bev); + + conn->rev = event_new (conn->evb, conn->fd, EV_READ|EV_PERSIST, _evcb, NULL); + conn->wev = event_new (conn->evb, conn->fd, EV_WRITE, _evcb, NULL); + if (!conn->rev || !conn->wev) + { + if (conn->rev) + event_free (conn->rev); + /* ENOMEM _or_ EINVAL but EINVAL only if we use EV_SIGNAL, at + least for now (libevent-2.0.5). */ + return rs_err_conn_push_fl (conn, RSE_NOMEM, __FILE__, __LINE__, NULL); + } + return RSE_OK; +} + +int +udp_init_retransmit_timer (struct rs_connection *conn) +{ + assert (conn); + + if (conn->tev) + event_free (conn->tev); + conn->tev = evtimer_new (conn->evb, event_retransmit_timeout_cb, conn); + if (!conn->tev) + return rs_err_conn_push_fl (conn, RSE_EVENT, __FILE__, __LINE__, + "evtimer_new"); + + return RSE_OK; +} |