Restructure code, moving most code out of packet.c

Also, move copyright notice out of COPYING and into every file.

1 files changed, 276 insertions, 0 deletions

diff --git a/lib/tcp.c b/lib/tcp.c
new file mode 100644
index 0000000..2e641f6
--- /dev/null
+++ b/lib/tcp.c
@@ -0,0 +1,276 @@
+/* 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 <event2/event.h>
+#include <event2/bufferevent.h>
+#if defined (RS_ENABLE_TLS)
+#include <event2/bufferevent_ssl.h>
+#include <openssl/err.h>
+#endif
+#include <radsec/radsec.h>
+#include <radsec/radsec-impl.h>
+#include "tcp.h"
+#include "packet.h"
+#include "debug.h"
+#include "event.h"
+
+#if defined (DEBUG)
+#include <event2/buffer.h>
+#endif
+
+static int
+_close_conn (struct rs_connection **connp)
+{
+  int r;
+  assert (connp);
+  assert (*connp);
+  r = rs_conn_destroy (*connp);
+  if (!r)
+    *connp = NULL;
+  return r;
+}
+
+/* Read one RADIUS packet header.  Return !0 on error.  A return value
+   of 0 means that we need more data.  */
+static int
+_read_header (struct rs_packet *pkt)
+{
+  size_t n = 0;
+
+  n = bufferevent_read (pkt->conn->bev, pkt->hdr, RS_HEADER_LEN);
+  if (n == RS_HEADER_LEN)
+    {
+      pkt->hdr_read_flag = 1;
+      pkt->rpkt->data_len = (pkt->hdr[2] << 8) + pkt->hdr[3];
+      if (pkt->rpkt->data_len < 20 || pkt->rpkt->data_len > 4096)
+	{
+	  _close_conn (&pkt->conn);
+	  return rs_err_conn_push (pkt->conn, RSE_INVALID_PKT,
+				   "invalid packet length: %d",
+				   pkt->rpkt->data_len);
+	}
+      pkt->rpkt->data = rs_malloc (pkt->conn->ctx, pkt->rpkt->data_len);
+      if (!pkt->rpkt->data)
+	{
+	  _close_conn (&pkt->conn);
+	  return rs_err_conn_push_fl (pkt->conn, RSE_NOMEM, __FILE__, __LINE__,
+				      NULL);
+	}
+      memcpy (pkt->rpkt->data, pkt->hdr, RS_HEADER_LEN);
+      bufferevent_setwatermark (pkt->conn->bev, EV_READ,
+				pkt->rpkt->data_len - RS_HEADER_LEN, 0);
+      rs_debug (("%s: packet header read, total pkt len=%d\n",
+		 __func__, pkt->rpkt->data_len));
+    }
+  else if (n < 0)
+    {
+      rs_debug (("%s: buffer frozen while reading header\n", __func__));
+    }
+  else	    /* Error: libevent gave us less than the low watermark. */
+    {
+      _close_conn (&pkt->conn);
+      return rs_err_conn_push_fl (pkt->conn, RSE_INTERNAL, __FILE__, __LINE__,
+				  "got %d octets reading header", n);
+    }
+
+  return 0;
+}
+
+static int
+_read_packet (struct rs_packet *pkt)
+{
+  size_t n = 0;
+
+  rs_debug (("%s: trying to read %d octets of packet data\n", __func__,
+	     pkt->rpkt->data_len - RS_HEADER_LEN));
+
+  n = bufferevent_read (pkt->conn->bev,
+			pkt->rpkt->data + RS_HEADER_LEN,
+			pkt->rpkt->data_len - RS_HEADER_LEN);
+
+  rs_debug (("%s: read %ld octets of packet data\n", __func__, n));
+
+  if (n == pkt->rpkt->data_len - RS_HEADER_LEN)
+    {
+      bufferevent_disable (pkt->conn->bev, EV_READ);
+      rs_debug (("%s: complete packet read\n", __func__));
+      pkt->hdr_read_flag = 0;
+      memset (pkt->hdr, 0, sizeof(*pkt->hdr));
+
+      /* Checks done by rad_packet_ok:
+	 - lenghts (FIXME: checks really ok for tcp?)
+	 - invalid code field
+	 - attribute lengths >= 2
+	 - attribute sizes adding up correctly  */
+      if (!rad_packet_ok (pkt->rpkt, 0) != 0)
+	{
+	  _close_conn (&pkt->conn);
+	  return rs_err_conn_push_fl (pkt->conn, RSE_FR, __FILE__, __LINE__,
+				      "invalid packet: %s", fr_strerror ());
+	}
+
+      /* TODO: Verify that reception of an unsolicited response packet
+	 results in connection being closed.  */
+
+      /* If we have a request to match this response against, verify
+	 and decode the response.  */
+      if (pkt->original)
+	{
+	  /* Verify header and message authenticator.  */
+	  if (rad_verify (pkt->rpkt, pkt->original->rpkt,
+			  pkt->conn->active_peer->secret))
+	    {
+	      _close_conn (&pkt->conn);
+	      return rs_err_conn_push_fl (pkt->conn, RSE_FR, __FILE__, __LINE__,
+					  "rad_verify: %s", fr_strerror ());
+	    }
+
+	  /* Decode and decrypt.  */
+	  if (rad_decode (pkt->rpkt, pkt->original->rpkt,
+			  pkt->conn->active_peer->secret))
+	    {
+	      _close_conn (&pkt->conn);
+	      return rs_err_conn_push_fl (pkt->conn, RSE_FR, __FILE__, __LINE__,
+					  "rad_decode: %s", fr_strerror ());
+	    }
+	}
+
+#if defined (DEBUG)
+      /* Find out what happens if there's data left in the buffer.  */
+      {
+	size_t rest = 0;
+	rest = evbuffer_get_length (bufferevent_get_input (pkt->conn->bev));
+	if (rest)
+	  rs_debug (("%s: returning with %d octets left in buffer\n", __func__,
+		     rest));
+      }
+#endif
+
+      /* Hand over message to user, 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 (n < 0)		/* Buffer frozen.  */
+    rs_debug (("%s: buffer frozen when reading packet\n", __func__));
+  else				/* Short packet.  */
+    rs_debug (("%s: waiting for another %d octets\n", __func__,
+	       pkt->rpkt->data_len - RS_HEADER_LEN - n));
+
+  return 0;
+}
+
+/* Read callback for TCP.
+
+   Read exactly one RADIUS message from BEV and store it in struct
+   rs_packet passed in CTX (hereby called 'pkt').
+
+   Verify the received packet against pkt->original, if !NULL.
+
+   Inform upper layer about successful reception of valid RADIUS
+   message by invoking conn->callbacks.recevied_cb(), if !NULL.  */
+void
+tcp_read_cb (struct bufferevent *bev, void *user_data)
+{
+  struct rs_packet *pkt = (struct rs_packet *) user_data;
+
+  assert (pkt);
+  assert (pkt->conn);
+  assert (pkt->rpkt);
+
+  pkt->rpkt->sockfd = pkt->conn->fd;
+  pkt->rpkt->vps = NULL;
+
+  if (!pkt->hdr_read_flag)
+    if (_read_header (pkt))
+      return;
+  _read_packet (pkt);
+}
+
+void
+tcp_event_cb (struct bufferevent *bev, short events, void *user_data)
+{
+  struct rs_packet *pkt = (struct rs_packet *) user_data;
+  struct rs_connection *conn = NULL;
+  struct rs_peer *p = NULL;
+  int sockerr = 0;
+#if defined (RS_ENABLE_TLS)
+  unsigned long tlserr = 0;
+#endif
+
+  assert (pkt);
+  assert (pkt->conn);
+  assert (pkt->conn->active_peer);
+  conn = pkt->conn;
+  p = conn->active_peer;
+
+  conn->is_connecting = 0;
+  if (events & BEV_EVENT_CONNECTED)
+    {
+      event_on_connect (conn, pkt);
+    }
+  else if (events & BEV_EVENT_EOF)
+    {
+      event_on_disconnect (conn);
+    }
+  else if (events & BEV_EVENT_TIMEOUT)
+    {
+      rs_debug (("%s: %p times out on %s\n", __func__, p,
+		 (events & BEV_EVENT_READING) ? "read" : "write"));
+      rs_err_conn_push_fl (pkt->conn, RSE_TIMEOUT_IO, __FILE__, __LINE__, NULL);
+    }
+  else if (events & BEV_EVENT_ERROR)
+    {
+      sockerr = evutil_socket_geterror (conn->active_peer->fd);
+      if (sockerr == 0)	/* FIXME: True that errno == 0 means closed? */
+	{
+	  event_on_disconnect (conn);
+	}
+      else
+	{
+	  rs_debug (("%s: %d: %d (%s)\n", __func__, conn->fd, sockerr,
+		     evutil_socket_error_to_string (sockerr)));
+	  rs_err_conn_push_fl (pkt->conn, RSE_SOCKERR, __FILE__, __LINE__,
+			       "%d: %d (%s)", conn->fd, sockerr,
+			       evutil_socket_error_to_string (sockerr));
+	}
+#if defined (RS_ENABLE_TLS)
+      if (conn->tls_ssl)	/* FIXME: correct check?  */
+	{
+	  for (tlserr = bufferevent_get_openssl_error (conn->bev);
+	       tlserr;
+	       tlserr = bufferevent_get_openssl_error (conn->bev))
+	    {
+	      rs_debug (("%s: openssl error: %s\n", __func__,
+			 ERR_error_string (tlserr, NULL)));
+	      rs_err_conn_push_fl (pkt->conn, RSE_SSLERR, __FILE__, __LINE__,
+				   ERR_error_string (tlserr, NULL));
+	    }
+	}
+#endif	/* RS_ENABLE_TLS */
+      event_loopbreak (conn);
+    }
+
+#if defined (DEBUG)
+  if (events & BEV_EVENT_ERROR && events != BEV_EVENT_ERROR)
+    rs_debug (("%s: BEV_EVENT_ERROR and more: 0x%x\n", __func__, events));
+#endif
+}
+
+void
+tcp_write_cb (struct bufferevent *bev, void *ctx)
+{
+  struct rs_packet *pkt = (struct rs_packet *) ctx;
+
+  assert (pkt);
+  assert (pkt->conn);
+
+  if (pkt->conn->callbacks.sent_cb)
+    pkt->conn->callbacks.sent_cb (pkt->conn->user_data);
+}
+