tuntap driver imported from http://jungerl.sourceforge.net/.

Makefile

@@ -0,0 +1,2 @@
+include ../../support/subdir.mk
+

README

@@ -0,0 +1,3 @@
+
+Copy of the tuntap Erlang driver from Jungerl, by Luke Gorrie.
+

c_src/Makefile

@@ -0,0 +1,23 @@
+include ../../../support/include.mk
+
+CFLAGS += -I $(ERL_C_INCLUDE_DIR) -I../../../support
+
+TUN_DRV_SO = ../priv/tun_drv.so
+TUNCTL = ../priv/tunctl
+
+all: $(TUN_DRV_SO) $(TUNCTL)
+
+$(TUN_DRV_SO): tun_drv.o
+	ld -G -o $@ $<
+
+tun_drv.o: tun_drv.c
+	$(CC) $(CFLAGS) -o $@ -c -fpic $(ERL_INCLUDE) $<
+
+$(TUNCTL): tunctl.c
+	$(CC) $(CFLAGS) -o $@ $<
+
+clean:
+	-rm $(TUN_DRV_SO) $(TUNCTL)
+
+.INTERMEDIATE: tun_drv.o
+

c_src/tun_drv.c

@@ -0,0 +1,247 @@
+/* Tunnel device linked-in driver.
+   See /usr/src/linux/Documentation/networking/tuntap.txt
+
+   Written by Luke Gorrie <luke@bluetail.com> in November 2001, and
+   updated in February 2003 to support TAP interfaces and the new
+   Erlang driver interface. */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <assert.h>
+
+#include <linux/if_tun.h>
+
+#include "erl_driver.h"
+
+#define REPLY_ERROR 0
+#define REPLY_OK    1
+
+#define REQUEST_GET_DEVICE 0
+#define REQUEST_ACTIVE     2
+
+#define ACTIVE_FALSE 0
+#define ACTIVE_TRUE  1
+#define ACTIVE_ONCE  2
+
+/* Generous buffer size for reading single ethernet frames.
+
+   FIXME: Do we need to worry about bigger packets, e.g. if we have a
+   giant MTU in 'tap' or receive pre-defragmented IP packets in
+   'tun'? */
+#define TUNNEL_BUF_SIZE 2048
+
+/*
+ *
+ * Helpers
+ *
+ */
+
+/* parse driver argument string: "tunnel_drv <tun|tap> [device_name]" */
+static int parse_args(char *str, int *mode, char *dev_name, int max_name_len)
+{
+    /* skip to start of first argument */
+    for (; *str != ' '; str++) { if (*str == '\0') return 0; }
+    for (; *str == ' '; str++) { if (*str == '\0') return 0; }
+
+    /* looking at "tun" or "tap" - parse and move over */
+    if (strncmp(str, "tun", 3) == 0) {
+        *mode = IFF_TUN;
+    } else if (strncmp(str, "tap", 3) == 0) {
+        *mode = IFF_TAP;
+    } else {
+        return 0;
+    }
+    str += 3;
+    /* optional device name - skip any whitespace, then copy */
+    while (*str == ' ') str++;
+    strncpy(dev_name, str, max_name_len);
+
+    return 1;
+}
+
+/* make a tunnel interface */
+static int make_if(int mode, char *dev) {
+    struct ifreq ifr;
+    int fd, err;
+
+    if ((fd = open("/dev/net/tun", O_RDWR | O_NONBLOCK)) < 0) return -1;
+
+    memset(&ifr, 0, sizeof(ifr));
+    ifr.ifr_flags = mode | IFF_NO_PI;
+    if( *dev )
+        strncpy(ifr.ifr_name, dev, IFNAMSIZ);
+
+    if( (err = ioctl(fd, TUNSETIFF, (void *) &ifr)) < 0 ){
+        close(fd);
+        return err;
+    }
+    strcpy(dev, ifr.ifr_name);
+    return fd;
+}
+
+
+/*
+ *
+ * erl_driver interface
+ *
+ */
+
+struct tun_state {
+    ErlDrvPort port;
+    int fd;
+    char dev[IFNAMSIZ];
+    char buf[TUNNEL_BUF_SIZE];
+    int active;
+};
+
+static int ctl_reply(int rep, char *buf, int len, char **rbuf, int rsize)
+{
+    char* ptr;
+
+    if ((len+1) > rsize) {
+	ptr = (char *)sys_alloc(len+1);
+        assert(ptr);
+	*rbuf = ptr;
+    }
+    else
+	ptr = *rbuf;
+    *ptr++ = rep;
+    memcpy(ptr, buf, len);
+    return len+1;
+}
+
+static void set_input(struct tun_state *state, int flag)
+{
+    driver_select(state->port, (ErlDrvEvent)state->fd, DO_READ, flag);
+}
+
+static int tun_ctl(ErlDrvData data,
+                   unsigned int cmd,
+                   char *buf,
+                   int len,
+                   char **rbuf,
+                   int rsize)
+{
+    struct tun_state *state = (struct tun_state *)data;
+    int read_len;
+    switch (cmd) {
+    case REQUEST_GET_DEVICE:
+        return ctl_reply(REPLY_OK, state->dev, strlen(state->dev), rbuf, rsize);
+    case REQUEST_ACTIVE:
+        state->active = (int)*buf;
+        switch (state->active) {
+        case ACTIVE_FALSE:
+            set_input(state, 0);
+            break;
+        case ACTIVE_TRUE:
+            set_input(state, 1);
+            break;
+        case ACTIVE_ONCE:
+            /* optimization: try to read a packet immediately if it
+               exists, to avoid going back to select() */
+            read_len = read(state->fd, state->buf, TUNNEL_BUF_SIZE);
+            if (read_len > 0) {
+                /* got a packet */
+                driver_output(state->port, state->buf, read_len);
+                state->active = ACTIVE_FALSE;
+                set_input(state, 0);
+            } else {
+                /* no packet available yet  */
+                set_input(state, 1);
+            }
+            break;
+        default:
+            assert(0);
+        }
+        return ctl_reply(REPLY_OK, "", 0, rbuf, rsize);
+    default:
+        return ctl_reply(REPLY_ERROR, "", 0, rbuf, rsize);
+    }
+}
+
+static void tun_output(ErlDrvData data, char* buf, int len)
+{
+    struct tun_state *state = (struct tun_state *)data;
+    if (write(state->fd, buf, len) < 0)
+	driver_failure_posix(state->port, errno);
+}
+
+static void tun_input(ErlDrvData data, ErlDrvEvent nil)
+{
+    struct tun_state *state = (struct tun_state *)data;
+    int len;
+
+    len = read(state->fd, state->buf, TUNNEL_BUF_SIZE);
+    if (len > 0) {
+        driver_output(state->port, state->buf, len);
+    }
+    if (state->active == ACTIVE_ONCE) {
+        state->active = ACTIVE_FALSE;
+        set_input(state, 0);
+    }
+}
+
+static void tun_stop(ErlDrvData data)
+{
+    struct tun_state *state = (struct tun_state *)data;
+    set_input(state, 0);
+    close(state->fd);
+    sys_free(state);
+}
+
+static ErlDrvData tun_start(ErlDrvPort port, char *args)
+{
+    struct tun_state *state;
+    int fd;
+
+    int mode;
+    char dev_name[IFNAMSIZ];
+
+    state = (struct tun_state*) sys_alloc(sizeof(struct tun_state));
+    if (state == NULL) {
+        errno = ENOMEM;         /* appropriate to set errno? */
+        return ERL_DRV_ERROR_ERRNO;
+    }
+
+    if (!parse_args(args, &mode, state->dev, IFNAMSIZ - 1)) {
+        return ERL_DRV_ERROR_BADARG;
+    }
+
+    fd = make_if(mode, state->dev);
+    if (fd < 0) {
+        return ERL_DRV_ERROR_GENERAL;
+    }
+    state->port = port;
+    state->fd = fd;
+    state->active = ACTIVE_FALSE;
+    set_input(state, 0);
+
+    return (ErlDrvData)state;
+}
+
+static int tun_init(void)
+{
+    return 0;
+}
+
+ErlDrvEntry tun_driver_entry;
+
+ErlDrvEntry *driver_init(void)
+{
+    memset(&tun_driver_entry, 0, sizeof(tun_driver_entry));
+    tun_driver_entry.init = tun_init;
+    tun_driver_entry.start = tun_start;
+    tun_driver_entry.stop = tun_stop;
+    tun_driver_entry.ready_input = tun_input;
+    tun_driver_entry.control = tun_ctl;
+    tun_driver_entry.output = tun_output;
+    tun_driver_entry.driver_name = "tun_drv";
+    return &tun_driver_entry;
+}
+

c_src/tunctl.c

@@ -0,0 +1,112 @@
+/* Copyright 2002 Jeff Dike
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <pwd.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <linux/if_tun.h>
+
+static void Usage(char *name)
+{
+  fprintf(stderr, "Create: %s [-b] [-u owner] [-t device-name] "
+	  "[-f tun-clone-device]\n", name);
+  fprintf(stderr, "Delete: %s -d device-name [-f tun-clone-device]\n\n", 
+	  name);
+  fprintf(stderr, "The default tun clone device is /dev/net/tun - some systems"
+	  " use\n/dev/misc/net/tun instead\n\n");
+  fprintf(stderr, "-b will result in brief output (just the device name)\n");
+  exit(1);
+}
+
+int main(int argc, char **argv)
+{
+  struct ifreq ifr;
+  struct passwd *pw;
+  long owner = geteuid();
+  int tap_fd, opt, delete = 0, brief = 0;
+  char *tun = "", *file = "/dev/net/tun", *name = argv[0], *end;
+
+  while((opt = getopt(argc, argv, "bd:f:t:u:")) > 0){
+    switch(opt) {
+      case 'b':
+        brief = 1;
+        break;
+      case 'd':
+        delete = 1;
+	tun = optarg;
+        break;
+      case 'f':
+	file = optarg;
+	break;
+      case 'u':
+	pw = getpwnam(optarg);
+	if(pw != NULL){
+	  owner = pw->pw_uid;
+	  break;
+	}
+        owner = strtol(optarg, &end, 0);
+	if(*end != '\0'){
+	  fprintf(stderr, "'%s' is neither a username nor a numeric uid.\n",
+		  optarg);
+	  Usage(name);
+	}
+        break;
+      case 't':
+        tun = optarg;
+        break;
+      case 'h':
+      default:
+        Usage(name);
+    }
+  }
+
+  argv += optind;
+  argc -= optind;
+
+  if(argc > 0)
+    Usage(name);
+
+  if((tap_fd = open(file, O_RDWR)) < 0){
+    perror("opening tun device");
+    exit(1);
+  }
+
+  memset(&ifr, 0, sizeof(ifr));
+
+  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+  strncpy(ifr.ifr_name, tun, sizeof(ifr.ifr_name) - 1);
+  if(ioctl(tap_fd, TUNSETIFF, (void *) &ifr) < 0){
+    perror("TUNSETIFF");
+    exit(1);
+  }
+
+  if(delete){
+    if(ioctl(tap_fd, TUNSETPERSIST, 0) < 0){
+      perror("TUNSETPERSIST");
+      exit(1);
+    }    
+    printf("Set '%s' nonpersistent\n", ifr.ifr_name);
+  }
+  else {
+    if(ioctl(tap_fd, TUNSETPERSIST, 1) < 0){
+      perror("TUNSETPERSIST");
+      exit(1);
+    }
+    if(ioctl(tap_fd, TUNSETOWNER, owner) < 0){
+      perror("TUNSETPERSIST");
+      exit(1);
+    } 
+    if(brief)
+      printf("%s\n", ifr.ifr_name);
+    else printf("Set '%s' persistent and owned by uid %ld\n", ifr.ifr_name, 
+		owner);
+  }
+  return(0);
+}

doc/short-desc

@@ -0,0 +1 @@
+Linux "Universal TUN/TAP device" driver