lwip: Add LwIP-based TCP/IP translator

* Makefile (prog-subdirs): Add lwip.
* config.make.in (HAVE_LIBLWIP, liblwip_CFLAGS, liblwip_LIBS): Define
variables.
* configure.ac: Check for liblwip.
* lwip/: New directory.

1 files changed, 573 insertions, 0 deletions

diff --git a/lwip/port/netif/hurdethif.c b/lwip/port/netif/hurdethif.c
new file mode 100644
index 00000000..bcf2e4dd
--- /dev/null
+++ b/lwip/port/netif/hurdethif.c
@@ -0,0 +1,573 @@
+/*
+   Copyright (C) 1995, 1996, 1998, 1999, 2000, 2002, 2007, 2017
+     Free Software Foundation, Inc.
+
+   Written by Michael I. Bushnell, p/BSG.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with the GNU Hurd.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/* Ethernet devices module */
+
+#include <netif/hurdethif.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <pthread.h>
+#include <error.h>
+#include <device/device.h>
+#include <device/net_status.h>
+#include <net/if.h>
+#include <net/if_arp.h>
+
+#include <lwip/opt.h>
+#include <lwip/def.h>
+#include <lwip/mem.h>
+#include <lwip/pbuf.h>
+#include <lwip/stats.h>
+#include <lwip/snmp.h>
+#include <lwip/ethip6.h>
+#include <lwip/etharp.h>
+
+/* Get the MAC address from an array of int */
+#define GET_HWADDR_BYTE(x,n)  (((char*)x)[n])
+
+static short ether_filter[] = {
+#ifdef NETF_IN
+  /* We have to tell the packet filtering code that we're interested in
+     incoming packets.  */
+  NETF_IN,			/* Header.  */
+#endif
+  NETF_PUSHLIT | NETF_NOP,
+  1
+};
+
+static int ether_filter_len = sizeof (ether_filter) / sizeof (short);
+
+static struct bpf_insn bpf_ether_filter[] = {
+  {NETF_IN | NETF_BPF, 0, 0, 0},	/* Header. */
+  {BPF_LD | BPF_H | BPF_ABS, 0, 0, 12},	/* Load Ethernet type */
+  {BPF_JMP | BPF_JEQ | BPF_K, 2, 0, 0x0806},	/* Accept ARP */
+  {BPF_JMP | BPF_JEQ | BPF_K, 1, 0, 0x0800},	/* Accept IPv4 */
+  {BPF_JMP | BPF_JEQ | BPF_K, 0, 1, 0x86DD},	/* Accept IPv6 */
+  /*
+   * And return an amount of bytes equal to:
+   * MSS + IP and transport headers length + Ethernet header length
+   */
+  {BPF_RET | BPF_K, 0, 0, TCP_MSS + 0x28 + PBUF_LINK_HLEN},
+  {BPF_RET | BPF_K, 0, 0, 0},	/* Or discard it all */
+};
+
+static int bpf_ether_filter_len = sizeof (bpf_ether_filter) / sizeof (short);
+
+/* Bucket and class for the incoming data */
+struct port_bucket *etherport_bucket;
+struct port_class *etherread_class;
+
+/* Thread for the incoming data */
+static pthread_t input_thread;
+
+/* Get the device flags */
+static error_t
+hurdethif_device_get_flags (struct netif *netif, uint16_t * flags)
+{
+  error_t err = 0;
+  size_t count;
+  struct net_status status;
+  hurdethif *ethif;
+
+  memset (&status, 0, sizeof (struct net_status));
+
+  ethif = netif_get_state (netif);
+  count = NET_STATUS_COUNT;
+  err = device_get_status (ethif->ether_port,
+			   NET_STATUS, (dev_status_t) & status, &count);
+  if (err == D_INVALID_OPERATION)
+    {
+      /*
+       * eth-multiplexer doesn't support setting flags.
+       * We must ignore D_INVALID_OPERATION.
+       */
+      error (0, 0, "%s: hardware doesn't support getting flags.\n",
+	     ethif->devname);
+      err = 0;
+    }
+  else if (err)
+    error (0, err, "%s: Cannot get hardware flags", ethif->devname);
+  else
+    *flags = status.flags;
+
+  return err;
+}
+
+/* Set the device flags */
+static error_t
+hurdethif_device_set_flags (struct netif *netif, uint16_t flags)
+{
+  error_t err = 0;
+  hurdethif *ethif;
+  int sflags;
+
+  sflags = flags;
+  ethif = netif_get_state (netif);
+
+  if (ethif->ether_port == MACH_PORT_NULL)
+    /* The device is closed */
+    return 0;
+
+  err = device_set_status (ethif->ether_port, NET_FLAGS, &sflags, 1);
+  if (err == D_INVALID_OPERATION)
+    {
+      /*
+       * eth-multiplexer doesn't support setting flags.
+       * We must ignore D_INVALID_OPERATION.
+       */
+      error (0, 0, "%s: hardware doesn't support setting flags.\n",
+	     ethif->devname);
+      err = 0;
+    }
+  else if (err)
+    error (0, err, "%s: Cannot set hardware flags", ethif->devname);
+  else
+    ethif->flags = flags;
+
+  return err;
+}
+
+/* Use the device interface to access the device */
+static error_t
+hurdethif_device_open (struct netif *netif)
+{
+  error_t err = ERR_OK;
+  device_t master_device;
+  hurdethif *ethif = netif_get_state (netif);
+
+  if (ethif->ether_port != MACH_PORT_NULL)
+    {
+      error (0, 0, "Already opened: %s", ethif->devname);
+      return -1;
+    }
+
+  err = ports_create_port (etherread_class, etherport_bucket,
+			   sizeof (struct port_info), &ethif->readpt);
+  if (err)
+    {
+      error (0, err, "ports_create_port on %s", ethif->devname);
+    }
+  else
+    {
+      ethif->readptname = ports_get_right (ethif->readpt);
+      mach_port_insert_right (mach_task_self (), ethif->readptname,
+			      ethif->readptname, MACH_MSG_TYPE_MAKE_SEND);
+
+      mach_port_set_qlimit (mach_task_self (), ethif->readptname,
+			    MACH_PORT_QLIMIT_MAX);
+
+      master_device = file_name_lookup (ethif->devname, O_RDWR, 0);
+      if (master_device != MACH_PORT_NULL)
+	{
+	  /* The device name here is the path of a device file.  */
+	  err = device_open (master_device, D_WRITE | D_READ,
+			     "eth", &ethif->ether_port);
+	  mach_port_deallocate (mach_task_self (), master_device);
+	  if (err)
+	    error (0, err, "device_open on %s", ethif->devname);
+	  else
+	    {
+	      err = device_set_filter (ethif->ether_port, ethif->readptname,
+				       MACH_MSG_TYPE_MAKE_SEND, 0,
+				       (filter_array_t) bpf_ether_filter,
+				       bpf_ether_filter_len);
+	      if (err)
+		error (0, err, "device_set_filter on %s", ethif->devname);
+	    }
+	}
+      else
+	{
+	  /* No, perhaps a Mach device?  */
+	  int file_errno = errno;
+	  err = get_privileged_ports (0, &master_device);
+	  if (err)
+	    {
+	      error (0, file_errno, "file_name_lookup %s", ethif->devname);
+	      error (0, err, "and cannot get device master port");
+	    }
+	  else
+	    {
+	      err = device_open (master_device, D_WRITE | D_READ,
+				 ethif->devname, &ethif->ether_port);
+	      mach_port_deallocate (mach_task_self (), master_device);
+	      if (err)
+		{
+		  error (0, file_errno, "file_name_lookup %s",
+			 ethif->devname);
+		  error (0, err, "device_open(%s)", ethif->devname);
+		}
+	      else
+		{
+		  err =
+		    device_set_filter (ethif->ether_port, ethif->readptname,
+				       MACH_MSG_TYPE_MAKE_SEND, 0,
+				       (filter_array_t) ether_filter,
+				       ether_filter_len);
+		  if (err)
+		    error (0, err, "device_set_filter on %s", ethif->devname);
+		}
+	    }
+	}
+    }
+
+  return err;
+}
+
+/* Destroy our link to the device */
+static error_t
+hurdethif_device_close (struct netif *netif)
+{
+  hurdethif *ethif = netif_get_state (netif);
+
+  if (ethif->ether_port == MACH_PORT_NULL)
+    {
+      error (0, 0, "Already closed: %s", ethif->devname);
+      return -1;
+    }
+
+  mach_port_deallocate (mach_task_self (), ethif->readptname);
+  ethif->readptname = MACH_PORT_NULL;
+  ports_destroy_right (ethif->readpt);
+  ethif->readpt = NULL;
+  device_close (ethif->ether_port);
+  mach_port_deallocate (mach_task_self (), ethif->ether_port);
+  ethif->ether_port = MACH_PORT_NULL;
+
+  return ERR_OK;
+}
+
+/*
+ * Called from lwip when outgoing data is ready
+ */
+static error_t
+hurdethif_output (struct netif *netif, struct pbuf *p)
+{
+  error_t err;
+  hurdethif *ethif = netif_get_state (netif);
+  int count;
+  uint8_t tried;
+
+  if (p->tot_len != p->len)
+    /* Drop the packet */
+    return ERR_OK;
+
+  tried = 0;
+  /* Send the data from the pbuf to the interface, one pbuf at a
+     time. The size of the data in each pbuf is kept in the ->len
+     variable. */
+  do
+    {
+      tried++;
+      err = device_write (ethif->ether_port, D_NOWAIT, 0,
+			  p->payload, p->len, &count);
+      if (err)
+	{
+	  if (tried == 2)
+	    /* Too many tries, abort */
+	    break;
+
+	  if (err == EMACH_SEND_INVALID_DEST || err == EMIG_SERVER_DIED)
+	    {
+	      /* Device probably just died, try to reopen it.  */
+	      hurdethif_device_close (netif);
+	      hurdethif_device_open (netif);
+	    }
+	}
+      else if (count != p->len)
+	/* Incomplete package sent, reattempt */
+	err = -1;
+    }
+  while (err);
+
+  return ERR_OK;
+}
+
+/*
+ * Called from the demuxer when incoming data is ready
+ */
+void
+hurdethif_input (struct netif *netif, struct net_rcv_msg *msg)
+{
+  struct pbuf *p, *q;
+  uint16_t len;
+  uint16_t off;
+  uint16_t next_read;
+
+  /* Get the size of the whole packet */
+  len = PBUF_LINK_HLEN
+    + msg->packet_type.msgt_number - sizeof (struct packet_header);
+
+  /* Allocate an empty pbuf chain for the data */
+  p = pbuf_alloc (PBUF_RAW, len, PBUF_POOL);
+
+  if (p)
+    {
+      /*
+       * Iterate to fill the pbuf chain.
+       * 
+       * First read the Ethernet header from msg->header. Then read the
+       * payload from msg->packet
+       */
+      q = p;
+      off = 0;
+      do
+	{
+	  if (off < PBUF_LINK_HLEN)
+	    {
+	      /* We still haven't ended copying the header */
+	      next_read = (off + q->len) > PBUF_LINK_HLEN ?
+		(PBUF_LINK_HLEN - off) : q->len;
+	      memcpy (q->payload, msg->header + off, next_read);
+
+	      if ((off + q->len) > PBUF_LINK_HLEN)
+		memcpy (q->payload + PBUF_LINK_HLEN,
+			msg->packet + sizeof (struct packet_header),
+			q->len - next_read);
+	    }
+	  else
+	    /* The header is copyied yet */
+	    memcpy (q->payload, msg->packet +
+		    sizeof (struct packet_header) + off - PBUF_LINK_HLEN,
+		    q->len);
+
+	  off += q->len;
+
+	  /* q->tot_len == q->len means this was the last pbuf in the chain */
+	  if (q->tot_len == q->len)
+	    break;
+	  else
+	    q = q->next;
+	}
+      while (1);
+
+      /* Pass the pbuf chain to he input function */
+      if (netif->input (p, netif) != ERR_OK)
+	{
+	  LWIP_DEBUGF (NETIF_DEBUG, ("hurdethif_input: IP input error\n"));
+	  pbuf_free (p);
+	  p = NULL;
+	}
+    }
+}
+
+/* Demux incoming RPCs from the device */
+int
+hurdethif_demuxer (mach_msg_header_t * inp, mach_msg_header_t * outp)
+{
+  struct net_rcv_msg *msg = (struct net_rcv_msg *) inp;
+  struct netif *netif;
+  mach_port_t local_port;
+
+  if (inp->msgh_id != NET_RCV_MSG_ID)
+    return 0;
+
+  if (MACH_MSGH_BITS_LOCAL (inp->msgh_bits) ==
+      MACH_MSG_TYPE_PROTECTED_PAYLOAD)
+    {
+      struct port_info *pi = ports_lookup_payload (NULL,
+						   inp->msgh_protected_payload,
+						   NULL);
+      if (pi)
+	{
+	  local_port = pi->port_right;
+	  ports_port_deref (pi);
+	}
+      else
+	local_port = MACH_PORT_NULL;
+    }
+  else
+    local_port = inp->msgh_local_port;
+
+  for (netif = netif_list; netif; netif = netif->next)
+    if (local_port == netif_get_state (netif)->readptname)
+      break;
+
+  if (!netif)
+    {
+      if (inp->msgh_remote_port != MACH_PORT_NULL)
+	mach_port_deallocate (mach_task_self (), inp->msgh_remote_port);
+      return 1;
+    }
+
+  hurdethif_input (netif, msg);
+
+  return 1;
+}
+
+/*
+ * Update the interface's MTU and the BPF filter
+ */
+static error_t
+hurdethif_device_update_mtu (struct netif *netif, uint32_t mtu)
+{
+  error_t err = 0;
+
+  netif->mtu = mtu;
+
+  bpf_ether_filter[5].k = mtu + PBUF_LINK_HLEN;
+
+  return err;
+}
+
+/*
+ * Release all resources of this netif.
+ *
+ * Returns 0 on success.
+ */
+static error_t
+hurdethif_device_terminate (struct netif *netif)
+{
+  /* Free the hook */
+  free (netif_get_state (netif)->devname);
+  free (netif_get_state (netif));
+
+  return 0;
+}
+
+/*
+ * Initializes a single device.
+ * 
+ * The module must be initialized before calling this function.
+ */
+error_t
+hurdethif_device_init (struct netif * netif)
+{
+  error_t err;
+  size_t count = 2;
+  int net_address[2];
+  device_t ether_port;
+  hurdethif *ethif;
+
+  /*
+   * Replace the hook by a new one with the proper size.
+   * The old one is in the stack and will be removed soon.
+   */
+  ethif = calloc (1, sizeof (hurdethif));
+  if (!ethif)
+    {
+      LWIP_DEBUGF (NETIF_DEBUG, ("hurdethif_init: out of memory\n"));
+      return ERR_MEM;
+    }
+  memcpy (ethif, netif_get_state (netif), sizeof (struct ifcommon));
+  netif->state = ethif;
+
+  /* Interface type */
+  ethif->type = ARPHRD_ETHER;
+
+  /* Set callbacks */
+  netif->output = etharp_output;
+  netif->output_ip6 = ethip6_output;
+  netif->linkoutput = hurdethif_output;
+
+  ethif->open = hurdethif_device_open;
+  ethif->close = hurdethif_device_close;
+  ethif->terminate = hurdethif_device_terminate;
+  ethif->update_mtu = hurdethif_device_update_mtu;
+  ethif->change_flags = hurdethif_device_set_flags;
+
+  /* ---- Hardware initialization ---- */
+
+  /* We need the device to be opened to configure it */
+  err = hurdethif_device_open (netif);
+  if (err)
+    return err;
+
+  /* Get the MAC address */
+  ether_port = netif_get_state (netif)->ether_port;
+  err = device_get_status (ether_port, NET_ADDRESS, net_address, &count);
+  if (err)
+    error (0, err, "%s: Cannot get hardware Ethernet address",
+	   netif_get_state (netif)->devname);
+  else if (count * sizeof (int) >= ETHARP_HWADDR_LEN)
+    {
+      net_address[0] = ntohl (net_address[0]);
+      net_address[1] = ntohl (net_address[1]);
+
+      /* Set MAC hardware address length */
+      netif->hwaddr_len = ETHARP_HWADDR_LEN;
+
+      /* Set MAC hardware address */
+      netif->hwaddr[0] = GET_HWADDR_BYTE (net_address, 0);
+      netif->hwaddr[1] = GET_HWADDR_BYTE (net_address, 1);
+      netif->hwaddr[2] = GET_HWADDR_BYTE (net_address, 2);
+      netif->hwaddr[3] = GET_HWADDR_BYTE (net_address, 3);
+      netif->hwaddr[4] = GET_HWADDR_BYTE (net_address, 4);
+      netif->hwaddr[5] = GET_HWADDR_BYTE (net_address, 5);
+    }
+  else
+    error (0, 0, "%s: Invalid Ethernet address",
+	   netif_get_state (netif)->devname);
+
+  /* Maximum transfer unit: MSS + IP header size + TCP header size */
+  netif->mtu = TCP_MSS + 20 + 20;
+
+  /* Enable Ethernet multicasting */
+  hurdethif_device_get_flags (netif, &netif_get_state (netif)->flags);
+  netif_get_state (netif)->flags |=
+    IFF_UP | IFF_RUNNING | IFF_BROADCAST | IFF_ALLMULTI;
+  hurdethif_device_set_flags (netif, netif_get_state (netif)->flags);
+
+  /*
+   * Up the link, set the interface type to NETIF_FLAG_ETHARP
+   * and enable other features.
+   */
+  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP
+    | NETIF_FLAG_IGMP | NETIF_FLAG_MLD6;
+
+  return ERR_OK;
+}
+
+static void *
+hurdethif_input_thread (void *arg)
+{
+  ports_manage_port_operations_one_thread (etherport_bucket,
+					   hurdethif_demuxer, 0);
+
+  return 0;
+}
+
+/*
+ * Init the thread for the incoming data.
+ *
+ * This function should be called once.
+ */
+error_t
+hurdethif_module_init ()
+{
+  error_t err;
+  etherport_bucket = ports_create_bucket ();
+  etherread_class = ports_create_class (0, 0);
+
+  err = pthread_create (&input_thread, 0, hurdethif_input_thread, 0);
+  if (!err)
+    pthread_detach (input_thread);
+  else
+    {
+      errno = err;
+      perror ("pthread_create");
+    }
+
+  return err;
+}