debian compatable ifup and ifdown commands

5 files changed, 1478 insertions, 0 deletions

diff --git a/include/applets.h b/include/applets.h
index e41a48996..2de9c9909 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -239,6 +239,12 @@
 #ifdef CONFIG_IFCONFIG
         APPLET(ifconfig, ifconfig_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
 #endif
+#ifdef CONFIG_IFUPDOWN
+        APPLET(ifdown, ifupdown_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
+#endif
+#ifdef CONFIG_IFUPDOWN
+        APPLET(ifup, ifupdown_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_INIT
         APPLET(init, init_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
 #endif
diff --git a/include/usage.h b/include/usage.h
index 1d22806f1..2d20722a9 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -807,6 +807,34 @@
         USAGE_IFCONFIG_MII("\t[mem_start <NN>]  [io_addr <NN>]  [irq <NN>]\n") \
         "\t[up|down] ..."
 
+#define ifup_trivial_usage \
+        "<-ahinv> <ifaces...>"
+#define ifup_full_usage \
+        "Usage: ifup <options> <ifaces...>\n\n" \
+        "Options:\n" \
+        "\t-h, --help\t\tthis help\n" \
+        "\t-a, --all\t\tde/configure all interfaces automatically\n" \
+        "\t-i, --interfaces FILE\tuse FILE for interface definitions\n" \
+    "\t-n, --no-act\t\tprint out what would happen, but don't do it\n" \
+        "\t\t\t\t(note that this option doesn't disable mappings)\n" \
+    "\t-v, --verbose\t\tprint out what would happen before doing it\n" \
+        "\t--no-mappings\t\tdon't run any mappings\n" \
+        "\t--force\t\t\tforce de/configuration\n"
+
+#define ifdown_trivial_usage \
+        "<-ahinv> <ifaces...>"
+#define ifdown_full_usage \
+        "Usage: ifdown <options> <ifaces...>\n\n" \
+        "Options:\n" \
+        "\t-h, --help\t\tthis help\n" \
+        "\t-a, --all\t\tde/configure all interfaces automatically\n" \
+        "\t-i, --interfaces FILE\tuse FILE for interface definitions\n" \
+    "\t-n, --no-act\t\tprint out what would happen, but don't do it\n" \
+        "\t\t\t\t(note that this option doesn't disable mappings)\n" \
+    "\t-v, --verbose\t\tprint out what would happen before doing it\n" \
+        "\t--no-mappings\t\tdon't run any mappings\n" \
+        "\t--force\t\t\tforce de/configuration\n"
+        
 #define init_trivial_usage \
         ""
 #define init_full_usage \
diff --git a/networking/Makefile.in b/networking/Makefile.in
index d6c8592d2..743990bb6 100644
--- a/networking/Makefile.in
+++ b/networking/Makefile.in
@@ -25,6 +25,7 @@ endif
 NETWORKING-y:=
 NETWORKING-$(CONFIG_HOSTNAME)           += hostname.o
 NETWORKING-$(CONFIG_IFCONFIG)           += ifconfig.o
+NETWORKING-$(CONFIG_IFUPDOWN)           += ifupdown.o
 NETWORKING-$(CONFIG_NC)                 += nc.o
 NETWORKING-$(CONFIG_NETSTAT)            += netstat.o
 NETWORKING-$(CONFIG_NSLOOKUP)           += nslookup.o
diff --git a/networking/config.in b/networking/config.in
index bc14940d5..09b2b5c6f 100644
--- a/networking/config.in
+++ b/networking/config.in
@@ -16,6 +16,12 @@ if [ "$CONFIG_IFCONFIG" = "y" ]; then
     bool '  Enable option "hw" (ether only)'                                            CONFIG_FEATURE_IFCONFIG_HW 
     bool '  Set the broadcast automatically'                                    CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 fi
+bool 'ifupdown'     CONFIG_IFUPDOWN
+if [ "$CONFIG_IFUPDOWN" = "y" ]; then
+    bool '  Enable support for IPv4'    CONFIG_FEATURE_IFUPDOWN_IPV4
+    bool '  Enable support for IPv6 (requires ip command)' CONFIG_FEATURE_IFUPDOWN_IPV6
+    bool '  Enable support for IPX (requires ipx_interface command)' CONFIG_FEATURE_IFUPDOWN_IPX
+fi
 bool 'nc'           CONFIG_NC
 bool 'netstat'      CONFIG_NETSTAT
 bool 'nslookup'     CONFIG_NSLOOKUP
diff --git a/networking/ifupdown.c b/networking/ifupdown.c
new file mode 100644
index 000000000..f56842dc7
--- /dev/null
+++ b/networking/ifupdown.c
@@ -0,0 +1,1437 @@
+/*
+ *  ifupdown for busybox
+ *  Based on ifupdown by Anthony Towns
+ *  Copyright (c) 1999 Anthony Towns <aj@azure.humbug.org.au>
+ *
+ *  Remove checks for kernel version, assume kernel version 2.2.0 or better
+ *
+ *  This program 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 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program 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 this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <sys/wait.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <fnmatch.h>
+#include <getopt.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "busybox.h"
+#include "config.h"
+
+#define IFUPDOWN_VERSION "0.6.4"
+
+typedef struct interface_defn interface_defn;
+
+typedef int (execfn)(char *command);
+typedef int (command_set)(interface_defn *ifd, execfn *e);
+
+typedef struct method {
+        char *name;
+        command_set *up;
+        command_set *down;
+} method;
+
+typedef struct address_family {
+        char *name;
+        int n_methods;
+        method *method;
+} address_family;
+
+typedef struct mapping_defn {
+        struct mapping_defn *next;
+
+        int max_matches;
+        int n_matches;
+        char **match;
+
+        char *script;
+
+        int max_mappings;
+        int n_mappings;
+        char **mapping;
+} mapping_defn;
+
+typedef struct variable {
+        char *name;
+        char *value;
+} variable;
+
+struct interface_defn {
+        struct interface_defn *next;
+
+        char *iface;
+        address_family *address_family;
+        method *method;
+
+        int automatic;
+
+        int max_options;
+        int n_options;
+        variable *option;
+};
+
+typedef struct interfaces_file {
+        int max_autointerfaces;
+        int n_autointerfaces;
+        char **autointerfaces;
+
+        interface_defn *ifaces;
+        mapping_defn *mappings;
+} interfaces_file;
+
+#define MAX_OPT_DEPTH 10
+#define EUNBALBRACK 10001
+#define EUNDEFVAR   10002
+#define MAX_VARNAME    32
+#define EUNBALPER   10000
+
+static int no_act = 0;
+static int verbose = 0;
+static char **environ = NULL;
+
+static int execable(char *program)
+{
+        struct stat buf;
+        if (0 == stat(program, &buf)) {
+                if (S_ISREG(buf.st_mode) && (S_IXUSR & buf.st_mode)) {
+                        return(1);
+                }
+        }
+        return(0);
+}
+
+static void addstr(char **buf, size_t *len, size_t *pos, char *str, size_t str_length)
+{
+        if (*pos + str_length >= *len) {
+                char *newbuf;
+
+                newbuf = xrealloc(*buf, *len * 2 + str_length + 1);
+                *buf = newbuf;
+                *len = *len * 2 + str_length + 1;
+        }
+
+        while (str_length-- >= 1) {
+                (*buf)[(*pos)++] = *str;
+                str++;
+        }
+        (*buf)[*pos] = '\0';
+}
+
+static int strncmpz(char *l, char *r, size_t llen)
+{
+        int i = strncmp(l, r, llen);
+
+        if (i == 0) {
+                return(-r[llen]);
+        } else {
+                return(i);
+        }
+}
+
+static char *get_var(char *id, size_t idlen, interface_defn *ifd)
+{
+        int i;
+
+        if (strncmpz(id, "iface", idlen) == 0) {
+                return (ifd->iface);
+        } else {
+                for (i = 0; i < ifd->n_options; i++) {
+                        if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
+                                return (ifd->option[i].value);
+                        }
+                }
+        }
+
+        return(NULL);
+}
+
+static char *parse(char *command, interface_defn *ifd)
+{
+
+        char *result = NULL;
+        size_t pos = 0, len = 0;
+        size_t old_pos[MAX_OPT_DEPTH] = { 0 };
+        int okay[MAX_OPT_DEPTH] = { 1 };
+        int opt_depth = 1;
+
+        while (*command) {
+                switch (*command) {
+
+                default:
+                        addstr(&result, &len, &pos, command, 1);
+                        command++;
+                        break;
+                case '\\':
+                        if (command[1]) {
+                                addstr(&result, &len, &pos, command + 1, 1);
+                                command += 2;
+                        } else {
+                                addstr(&result, &len, &pos, command, 1);
+                                command++;
+                        }
+                        break;
+                case '[':
+                        if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
+                                old_pos[opt_depth] = pos;
+                                okay[opt_depth] = 1;
+                                opt_depth++;
+                                command += 2;
+                        } else {
+                                addstr(&result, &len, &pos, "[", 1);
+                                command++;
+                        }
+                        break;
+                case ']':
+                        if (command[1] == ']' && opt_depth > 1) {
+                                opt_depth--;
+                                if (!okay[opt_depth]) {
+                                        pos = old_pos[opt_depth];
+                                        result[pos] = '\0';
+                                }
+                                command += 2;
+                        } else {
+                                addstr(&result, &len, &pos, "]", 1);
+                                command++;
+                        }
+                        break;
+                case '%':
+                {
+                        char *nextpercent;
+                        char *varvalue;
+
+                        command++;
+                        nextpercent = strchr(command, '%');
+                        if (!nextpercent) {
+                                errno = EUNBALPER;
+                                free(result);
+                                return (NULL);
+                        }
+
+                        varvalue = get_var(command, nextpercent - command, ifd);
+
+                        if (varvalue) {
+                                addstr(&result, &len, &pos, varvalue, xstrlen(varvalue));
+                        } else {
+                                okay[opt_depth - 1] = 0;
+                        }
+
+                        command = nextpercent + 1;
+                }
+                        break;
+                }
+        }
+
+        if (opt_depth > 1) {
+                errno = EUNBALBRACK;
+                free(result);
+                return(NULL);
+        }
+
+        if (!okay[0]) {
+                errno = EUNDEFVAR;
+                free(result);
+                return(NULL);
+        }
+
+        return(result);
+}
+
+static int execute(char *command, interface_defn *ifd, execfn *exec)
+{
+        char *out;
+        int ret;
+
+        out = parse(command, ifd);
+        if (!out) {
+                return(0);
+        }
+
+        ret = (*exec) (out);
+
+        free(out);
+        return(ret);
+}
+
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPX
+static int static_up_ipx(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ipx_interface add %iface% %frame% %netnum%", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int static_down_ipx(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ipx_interface del %iface% %frame%", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int dynamic_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ipx_interface add %iface% %frame%", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int dynamic_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ipx_interface del %iface% %frame%", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static method methods_ipx[] = {
+        { "dynamic", dynamic_up, dynamic_down, },
+        { "static", static_up_ipx, static_down_ipx, },
+};
+
+address_family addr_ipx = {
+        "ipx",
+        sizeof(methods_ipx) / sizeof(struct method),
+        methods_ipx
+};
+#endif /* IFUP_FEATURE_IPX */
+
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
+static int loopback_up6(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% add ::1", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int loopback_down6(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% del ::1", ifd, exec))
+                return(0);
+        }
+        return(1);
+}
+
+static int static_up6(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% [[media %media%]] [[hw %hwaddress%]] [[mtu %mtu%]] up", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("ifconfig %iface% add %address%/%netmask%", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("[[ route -A inet6 add ::/0 gw %gateway% ]]", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int static_down6(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% down", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int v4tunnel_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ip tunnel add %iface% mode sit remote %endpoint% [[local %local%]] [[ttl %ttl%]]", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("ip link set %iface% up", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int v4tunnel_down(interface_defn * ifd, execfn * exec)
+{
+        if (!execute("ip tunnel del %iface%", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static method methods6[] = {
+        { "v4tunnel", v4tunnel_up, v4tunnel_down, },
+        { "static", static_up6, static_down6, },
+        { "loopback", loopback_up6, loopback_down6, },
+};
+
+address_family addr_inet6 = {
+        "inet6",
+        sizeof(methods6) / sizeof(struct method),
+        methods6
+};
+#endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
+
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
+static int loopback_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% 127.0.0.1 up", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int loopback_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% down", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int static_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig %iface% %address% netmask %netmask% [[broadcast %broadcast%]]    [[pointopoint %pointopoint%]] [[media %media%]] [[mtu %mtu%]]   [[hw %hwaddress%]] up",
+                 ifd, exec)) {
+                return(0);
+        }
+        if (!execute("[[ route add default gw %gateway% %iface% ]]", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int static_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("[[ route del default gw %gateway% %iface% ]]", ifd, exec)) {
+                return(0);
+        }
+        if (!execute("ifconfig %iface% down", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int dhcp_up(interface_defn *ifd, execfn *exec)
+{
+        if (execable("/sbin/dhclient")) {
+                if (!execute("dhclient -pf /var/run/dhclient.%iface%.pid %iface%", ifd, exec)) {
+                        return(0);
+                }
+        } else if (execable("/sbin/pump")) {
+                if (!execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]", ifd, exec)) {
+                        return(0);
+                }
+        } else if (execable("/sbin/udhcpc")) {
+                if (!execute("udhcpc -n -p /var/run/udhcpc.%iface%.pid -i %iface% [[-H %hostname%]] [[-c %clientid%]]", ifd, exec)) {
+                        return 0;
+                }
+        } else if (execable("/sbin/dhcpcd")) {
+                if (!execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] [[-l %leasetime%]] %iface%", ifd, exec)) {
+                        return(0);
+                }
+        }
+        return(1);
+}
+
+static int dhcp_down(interface_defn *ifd, execfn *exec)
+{
+        if (execable("/sbin/dhclient")) {
+                if (!execute("cat /var/run/dhclient.%iface%.pid | xargs -i kill -TERM {}", ifd, exec)) {
+                        return(0);
+                }
+        } else if (execable("/sbin/pump")) {
+                if (!execute("pump -i %iface% -k", ifd, exec)) {
+                        return(0);
+                }
+        } else if (execable("/sbin/udhcpc")) {
+                if (!execute("cat /var/run/udhcpc.%iface%.pid | xargs -i kill -TERM {}", ifd, exec)) {
+                        return(0);
+                }
+        } else if (execable("/sbin/dhcpcd")) {
+                if (!execute("dhcpcd -k %iface%", ifd, exec)) {
+                        return(0);
+                }
+        }
+        if (!execute("ifconfig %iface% down", ifd, exec)) {
+                return(0);
+        }
+        return(1);
+}
+
+static int bootp_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("bootpc [[--bootfile %bootfile%]] --dev %iface% [[--server %server%]]            [[--hwaddr %hwaddr%]] --returniffail --serverbcast", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static int bootp_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("ifconfig down %iface%", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static int ppp_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("pon [[%provider%]]", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static int ppp_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("poff [[%provider%]]", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static int wvdial_up(interface_defn *ifd, execfn *exec)
+{
+        if (!execute("/sbin/start-stop-daemon --start -x /usr/bin/wvdial -p /var/run/wvdial.%iface% -b -m -- [[ %provider% ]]", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static int wvdial_down(interface_defn *ifd, execfn *exec)
+{
+        if (!execute ("/sbin/start-stop-daemon --stop -x /usr/bin/wvdial -p /var/run/wvdial.%iface% -s 2", ifd, exec)) {
+                return 0;
+        }
+        return 1;
+}
+
+static method methods[] = {
+        { "wvdial", wvdial_up, wvdial_down, },
+        { "ppp", ppp_up, ppp_down, },
+        { "static", static_up, static_down, },
+        { "bootp", bootp_up, bootp_down, },
+        { "dhcp", dhcp_up, dhcp_down, },
+        { "loopback", loopback_up, loopback_down, },
+};
+
+address_family addr_inet = {
+        "inet",
+        sizeof(methods) / sizeof(struct method),
+        methods
+};
+
+#endif  /* ifdef CONFIG_FEATURE_IFUPDOWN_IPV4 */
+
+static char *next_word(char *buf, char *word, int maxlen)
+{
+        if (!buf)
+                return NULL;
+        if (!*buf)
+                return NULL;
+
+        while (!isspace(*buf) && *buf) {
+                if (maxlen-- > 1)
+                        *word++ = *buf;
+                buf++;
+        }
+        if (maxlen > 0) {
+                *word = '\0';
+        }
+
+        while (isspace(*buf) && *buf) {
+                buf++;
+        }
+
+        return buf;
+}
+
+static address_family *get_address_family(address_family *af[], char *name)
+{
+        int i;
+
+        for (i = 0; af[i]; i++) {
+                if (strcmp(af[i]->name, name) == 0) {
+                        return af[i];
+                }
+        }
+        return NULL;
+}
+
+static method *get_method(address_family *af, char *name)
+{
+        int i;
+
+        for (i = 0; i < af->n_methods; i++) {
+                if (strcmp(af->method[i].name, name) == 0) {
+                        return &af->method[i];
+                }
+        }
+        return(NULL);
+}
+
+static int duplicate_if(interface_defn *ifa, interface_defn *ifb)
+{
+        if (strcmp(ifa->iface, ifb->iface) != 0) {
+                return(0);
+        }
+        if (ifa->address_family != ifb->address_family) {
+                return(0);
+        }
+        return(1);
+}
+
+static int get_line(char **result, size_t * result_len, FILE * f, int *line)
+{
+        size_t pos;
+
+        do {
+                pos = 0;
+                do {
+                        if (*result_len - pos < 10) {
+                                char *newstr = xrealloc(*result, *result_len * 2 + 80);
+                                *result = newstr;
+                                *result_len = *result_len * 2 + 80;
+                        }
+
+                        if (!fgets(*result + pos, *result_len - pos, f)) {
+                                if (ferror(f) == 0 && pos == 0)
+                                        return 0;
+                                if (ferror(f) != 0)
+                                        return 0;
+                        }
+                        pos += xstrlen(*result + pos);
+                } while (pos == *result_len - 1 && (*result)[pos - 1] != '\n');
+
+                if (pos != 0 && (*result)[pos - 1] == '\n') {
+                        (*result)[--pos] = '\0';
+                }
+
+                (*line)++;
+                {
+                        int first = 0;
+
+                        while (isspace((*result)[first]) && (*result)[first]) {
+                                first++;
+                        }
+
+                        memmove(*result, *result + first, pos - first + 1);
+                        pos -= first;
+                }
+        } while ((*result)[0] == '#');
+
+        while ((*result)[pos - 1] == '\\') {
+                (*result)[--pos] = '\0';
+                do {
+                        if (*result_len - pos < 10) {
+                                char *newstr = xrealloc(*result, *result_len * 2 + 80);
+                                *result = newstr;
+                                *result_len = *result_len * 2 + 80;
+                        }
+
+                        if (!fgets(*result + pos, *result_len - pos, f)) {
+                                if (ferror(f) == 0 && pos == 0)
+                                        return 0;
+                                if (ferror(f) != 0)
+                                        return 0;
+                        }
+                        pos += xstrlen(*result + pos);
+                } while (pos == *result_len - 1 && (*result)[pos - 1] != '\n');
+
+                if (pos != 0 && (*result)[pos - 1] == '\n') {
+                        (*result)[--pos] = '\0';
+                }
+                (*line)++;
+        }
+
+        while (isspace((*result)[pos - 1])) {   /* remove trailing whitespace */
+                pos--;
+        }
+        (*result)[pos] = '\0';
+
+        return 1;
+}
+
+static interfaces_file *read_interfaces(char *filename)
+{
+        interface_defn *currif = NULL;
+        interfaces_file *defn;
+        mapping_defn *currmap = NULL;
+        FILE *f;
+        char firstword[80];
+        char *buf = NULL;
+        char *rest;
+        int line;
+        size_t buf_len = 0;
+
+        enum { NONE, IFACE, MAPPING } currently_processing = NONE;
+
+        defn = xmalloc(sizeof(interfaces_file));
+        defn->max_autointerfaces = defn->n_autointerfaces = 0;
+        defn->autointerfaces = NULL;
+        defn->mappings = NULL;
+        defn->ifaces = NULL;
+        f = fopen(filename, "r");
+        if (f == NULL) {
+                return NULL;
+        }
+        line = 0;
+
+        while (get_line(&buf, &buf_len, f, &line)) {
+                rest = next_word(buf, firstword, 80);
+                if (rest == NULL) {
+                        continue;       /* blank line */
+                }
+
+                if (strcmp(firstword, "mapping") == 0) {
+
+                        currmap = xmalloc(sizeof(mapping_defn));
+                        currmap->max_matches = 0;
+                        currmap->n_matches = 0;
+                        currmap->match = NULL;
+
+                        while ((rest = next_word(rest, firstword, 80))) {
+                                if (currmap->max_matches == currmap->n_matches) {
+                                        currmap->max_matches = currmap->max_matches * 2 + 1;
+                                        currmap->match = xrealloc(currmap->match, sizeof(currmap->match) * currmap->max_matches);
+                                }
+
+                                currmap->match[currmap->n_matches++] = xstrdup(firstword);
+                        }
+                        currmap->max_mappings = 0;
+                        currmap->n_mappings = 0;
+                        currmap->mapping = NULL;
+                        currmap->script = NULL;
+                        {
+                                mapping_defn **where = &defn->mappings;
+                                while (*where != NULL) {
+                                        where = &(*where)->next;
+                                }
+                                *where = currmap;
+                                currmap->next = NULL;
+                        }
+                        currently_processing = MAPPING;
+                } else if (strcmp(firstword, "iface") == 0) {
+                        {
+                                char iface_name[80];
+                                char address_family_name[80];
+                                char method_name[80];
+                                address_family *addr_fams[] = {
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
+                                        &addr_inet,
+#endif
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
+                                        &addr_inet6,
+#endif
+#ifdef CONFIG_FEATURE_IFUPDOWN_IPX
+                                        &addr_ipx,
+#endif
+                                        NULL
+                                };
+
+                                currif = xmalloc(sizeof(interface_defn));
+
+                                rest = next_word(rest, iface_name, 80);
+                                rest = next_word(rest, address_family_name, 80);
+                                rest = next_word(rest, method_name, 80);
+
+                                if (rest == NULL) {
+                                        error_msg("%s:%d: too few parameters for iface line", filename, line);
+                                        return NULL;
+                                }
+
+                                if (rest[0] != '\0') {
+                                        error_msg("%s:%d: too many parameters for iface line", filename, line);
+                                        return NULL;
+                                }
+
+                                currif->iface = xstrdup(iface_name);
+
+                                currif->address_family = get_address_family(addr_fams, address_family_name);
+                                if (!currif->address_family) {
+                                        error_msg("%s:%d: unknown address type", filename, line);
+                                        return NULL;
+                                }
+
+                                currif->method = get_method(currif->address_family, method_name);
+                                if (!currif->method) {
+                                        error_msg("%s:%d: unknown method", filename, line);
+                                        return NULL;
+                                }
+
+                                currif->automatic = 1;
+                                currif->max_options = 0;
+                                currif->n_options = 0;
+                                currif->option = NULL;
+
+
+                                {
+                                        interface_defn **where = &defn->ifaces;
+
+                                        while (*where != NULL) {
+                                                if (duplicate_if(*where, currif)) {
+                                                        error_msg("%s:%d: duplicate interface", filename, line);
+                                                        return NULL;
+                                                }
+                                                where = &(*where)->next;
+                                        }
+
+                                        *where = currif;
+                                        currif->next = NULL;
+                                }
+                        }
+                        currently_processing = IFACE;
+                } else if (strcmp(firstword, "auto") == 0) {
+                        while ((rest = next_word(rest, firstword, 80))) {
+                                int i;
+
+                                for (i = 0; i < defn->n_autointerfaces; i++) {
+                                        if (strcmp(firstword, defn->autointerfaces[i]) == 0) {
+                                                perror_msg("%s:%d: interface declared auto twice", filename, line);
+                                                return NULL;
+                                        }
+                                }
+
+                                if (defn->n_autointerfaces == defn->max_autointerfaces) {
+                                        char **tmp;
+
+                                        defn->max_autointerfaces *= 2;
+                                        defn->max_autointerfaces++;
+                                        tmp = xrealloc(defn->autointerfaces, sizeof(*tmp) * defn->max_autointerfaces);
+                                        defn->autointerfaces = tmp;
+                                }
+
+                                defn->autointerfaces[defn->n_autointerfaces] = xstrdup(firstword);
+                                defn->n_autointerfaces++;
+                        }
+                        currently_processing = NONE;
+                } else {
+                        switch (currently_processing) {
+                        case IFACE:
+                        {
+                                int i;
+
+                                if (xstrlen(rest) == 0) {
+                                        error_msg("%s:%d: option with empty value", filename, line);
+                                        return NULL;
+                                }
+
+                                if (strcmp(firstword, "up") != 0
+                                        && strcmp(firstword, "down") != 0
+                                        && strcmp(firstword, "pre-up") != 0
+                                        && strcmp(firstword, "post-down") != 0) {
+                                        for (i = 0; i < currif->n_options; i++) {
+                                                if (strcmp(currif->option[i].name, firstword) == 0) {
+                                                        error_msg("%s:%d: duplicate option", filename, line);
+                                                        return NULL;
+                                                }
+                                        }
+                                }
+                        }
+                                if (currif->n_options >= currif->max_options) {
+                                        variable *opt;
+
+                                        currif->max_options = currif->max_options + 10;
+                                        opt = xrealloc(currif->option, sizeof(*opt) * currif->max_options);
+                                        currif->option = opt;
+                                }
+                                currif->option[currif->n_options].name = xstrdup(firstword);
+                                currif->option[currif->n_options].value = xstrdup(rest);
+                                if (!currif->option[currif->n_options].name) {
+                                        perror(filename);
+                                        return NULL;
+                                }
+                                if (!currif->option[currif->n_options].value) {
+                                        perror(filename);
+                                        return NULL;
+                                }
+                                currif->n_options++;
+                                break;
+                        case MAPPING:
+                                if (strcmp(firstword, "script") == 0) {
+                                        if (currmap->script != NULL) {
+                                                error_msg("%s:%d: duplicate script in mapping", filename, line);
+                                                return NULL;
+                                        } else {
+                                                currmap->script = xstrdup(rest);
+                                        }
+                                } else if (strcmp(firstword, "map") == 0) {
+                                        if (currmap->max_mappings == currmap->n_mappings) {
+                                                currmap->max_mappings = currmap->max_mappings * 2 + 1;
+                                                currmap->mapping = xrealloc(currmap->mapping, sizeof(char *) * currmap->max_mappings);
+                                        }
+                                        currmap->mapping[currmap->n_mappings] = xstrdup(rest);
+                                        currmap->n_mappings++;
+                                } else {
+                                        error_msg("%s:%d: misplaced option", filename, line);
+                                        return NULL;
+                                }
+                                break;
+                        case NONE:
+                        default:
+                                error_msg("%s:%d: misplaced option", filename, line);
+                                return NULL;
+                        }
+                }
+        }
+        if (ferror(f) != 0) {
+                perror_msg("%s", filename);
+                return NULL;
+        }
+        fclose(f);
+        line = -1;
+
+        return defn;
+}
+
+static int check(char *str)
+{
+        return (str != NULL);
+}
+
+static char *setlocalenv(char *format, char *name, char *value)
+{
+        char *result;
+        char *here;
+        char *there;
+
+        result = xmalloc(xstrlen(format) + xstrlen(name) + xstrlen(value) + 1);
+
+        sprintf(result, format, name, value);
+
+        for (here = there = result; *there != '=' && *there; there++) {
+                if (*there == '-')
+                        *there = '_';
+                if (isalpha(*there))
+                        *there = toupper(*there);
+
+                if (isalnum(*there) || *there == '_') {
+                        *here = *there;
+                        here++;
+                }
+        }
+        memmove(here, there, xstrlen(there) + 1);
+
+        return result;
+}
+
+static void set_environ(interface_defn *iface, char *mode)
+{
+        char **environend;
+        int i;
+        const int n_env_entries = iface->n_options + 5;
+        char **ppch;
+
+        if (environ != NULL) {
+                for (ppch = environ; *ppch; ppch++) {
+                        free(*ppch);
+                        *ppch = NULL;
+                }
+                free(environ);
+                environ = NULL;
+        }
+        environ = xmalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
+        environend = environ;
+        *environend = NULL;
+
+        for (i = 0; i < iface->n_options; i++) {
+                if (strcmp(iface->option[i].name, "up") == 0
+                        || strcmp(iface->option[i].name, "down") == 0
+                        || strcmp(iface->option[i].name, "pre-up") == 0
+                        || strcmp(iface->option[i].name, "post-down") == 0) {
+                        continue;
+                }
+                *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
+                *environend = NULL;
+        }
+
+        *(environend++) = setlocalenv("%s=%s", "IFACE", iface->iface);
+        *environend = NULL;
+        *(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
+        *environend = NULL;
+        *(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
+        *environend = NULL;
+        *(environend++) = setlocalenv("%s=%s", "MODE", mode);
+        *environend = NULL;
+        *(environend++) = setlocalenv("%s=%s", "PATH", "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin");
+        *environend = NULL;
+}
+
+static int doit(char *str)
+{
+        if (verbose || no_act) {
+                error_msg("%s", str);
+        }
+        if (!no_act) {
+                pid_t child;
+                int status;
+
+                fflush(NULL);
+                switch (child = fork()) {
+                case -1:                /* failure */
+                        return 0;
+                case 0:         /* child */
+                        execle("/bin/sh", "/bin/sh", "-c", str, NULL, environ);
+                        exit(127);
+                default:                /* parent */
+                }
+                waitpid(child, &status, 0);
+                if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
+                        return 0;
+                }
+        }
+        return (1);
+}
+
+static int execute_all(interface_defn *ifd, execfn *exec, char *opt)
+{
+        int i;
+        char buf[100];
+
+        for (i = 0; i < ifd->n_options; i++) {
+                if (strcmp(ifd->option[i].name, opt) == 0) {
+                        if (!(*exec) (ifd->option[i].value)) {
+                                return 0;
+                        }
+                }
+        }
+
+        sprintf(buf, "run-parts /etc/network/if-%s.d", opt);
+        (*exec) (buf);
+
+        return (1);
+}
+
+static int iface_up(interface_defn *iface)
+{
+        if (!iface->method->up(iface, check)) {
+                return (-1);
+        }
+
+        set_environ(iface, "start");
+        if (!execute_all(iface, doit, "pre-up")) {
+                return (0);
+        }
+        if (!iface->method->up(iface, doit)) {
+                return (0);
+        }
+        if (!execute_all(iface, doit, "up")) {
+                return (0);
+        }
+
+        return (1);
+}
+
+static int iface_down(interface_defn *iface)
+{
+        if (!iface->method->down(iface, check)) {
+                return (-1);
+        }
+        set_environ(iface, "stop");
+        if (!execute_all(iface, doit, "down")) {
+                return (0);
+        }
+        if (!iface->method->down(iface, doit)) {
+                return (0);
+        }
+        if (!execute_all(iface, doit, "post-down")) {
+                return (0);
+        }
+        return (1);
+}
+
+static int popen2(FILE **in, FILE **out, char *command, ...)
+{
+        va_list ap;
+        char *argv[11] = { command };
+        int argc;
+        int infd[2], outfd[2];
+        pid_t pid;
+
+        argc = 1;
+        va_start(ap, command);
+        while ((argc < 10) && (argv[argc] = va_arg(ap, char *))) {
+                argc++;
+        }
+        argv[argc] = NULL;      /* make sure */
+        va_end(ap);
+
+        if (pipe(infd) != 0) {
+                return 0;
+        }
+
+        if (pipe(outfd) != 0) {
+                close(infd[0]);
+                close(infd[1]);
+                return 0;
+        }
+
+        fflush(NULL);
+        switch (pid = fork()) {
+        case -1:                        /* failure */
+                close(infd[0]);
+                close(infd[1]);
+                close(outfd[0]);
+                close(outfd[1]);
+                return 0;
+        case 0:                 /* child */
+                dup2(infd[0], 0);
+                dup2(outfd[1], 1);
+                close(infd[0]);
+                close(infd[1]);
+                close(outfd[0]);
+                close(outfd[1]);
+                execvp(command, argv);
+                exit(127);
+        default:                        /* parent */
+                *in = fdopen(infd[1], "w");
+                *out = fdopen(outfd[0], "r");
+                close(infd[0]);
+                close(outfd[1]);
+                return pid;
+        }
+        /* unreached */
+}
+
+static int run_mapping(char *physical, char *logical, int len, mapping_defn * map)
+{
+        FILE *in, *out;
+        int i, status;
+        pid_t pid;
+
+
+        pid = popen2(&in, &out, map->script, physical, NULL);
+        if (pid == 0) {
+                return 0;
+        }
+        for (i = 0; i < map->n_mappings; i++) {
+                fprintf(in, "%s\n", map->mapping[i]);
+        }
+        fclose(in);
+        waitpid(pid, &status, 0);
+        if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
+                if (fgets(logical, len, out)) {
+                        char *pch = logical + xstrlen(logical) - 1;
+
+                        while (pch >= logical && isspace(*pch))
+                                *(pch--) = '\0';
+                }
+        }
+        fclose(out);
+
+        return 1;
+}
+
+static int lookfor_iface(char **ifaces, int n_ifaces, char *iface)
+{
+        int i;
+
+        for (i = 0; i < n_ifaces; i++) {
+                if (strncmp(iface, ifaces[i], xstrlen(iface)) == 0) {
+                        if (ifaces[i][xstrlen(iface)] == '=') {
+                                return i;
+                        }
+                }
+        }
+
+        return(-1);
+}
+
+static void add_to_state(char ***ifaces, int *n_ifaces, int *max_ifaces, char *new_iface)
+{
+        if (*max_ifaces == *n_ifaces) {
+                *max_ifaces = (*max_ifaces * 2) + 1;
+                *ifaces = xrealloc(*ifaces, sizeof(**ifaces) * *max_ifaces);
+        }
+
+        (*ifaces)[(*n_ifaces)++] = new_iface;
+}
+
+extern int ifupdown_main(int argc, char **argv)
+{
+        int (*cmds) (interface_defn *) = NULL;
+        struct option long_opts[] = {
+                {"help", no_argument, NULL, 'h'},
+                {"verbose", no_argument, NULL, 'v'},
+                {"all", no_argument, NULL, 'a'},
+                {"interfaces", required_argument, NULL, 'i'},
+                {"no-act", no_argument, NULL, 'n'},
+                {"no-mappings", no_argument, NULL, 1},
+                {"force", no_argument, NULL, 2},
+                {0, 0, 0, 0}
+        };
+        interfaces_file *defn;
+        FILE *state_fp = NULL;
+        char **target_iface = NULL;
+        char **state = NULL;    /* list of iface=liface */
+        char *interfaces = "/etc/network/interfaces";
+        char *statefile = "/etc/network/ifstate";
+
+        int do_all = 0;
+        int run_mappings = 1;
+        int force = 0;
+        int n_target_ifaces = 0;
+        int n_state = 0;
+        int max_state = 0;
+        int i;
+
+        if (applet_name[2] == 'u') {
+                /* ifup command */
+                cmds = iface_up;
+        } else {
+                /* ifdown command */
+                cmds = iface_down;
+        }
+
+        while ((i = getopt_long(argc, argv, "i:hvna", long_opts, NULL)) != EOF) {
+                switch (i) {
+                case 'i':
+                        interfaces = xstrdup(optarg);
+                        break;
+                case 'v':
+                        verbose = 1;
+                        break;
+                case 'a':
+                        do_all = 1;
+                        break;
+                case 'n':
+                        no_act = 1;
+                        break;
+                case 1:
+                        run_mappings = 0;
+                        break;
+                case 2:
+                        force = 1;
+                        break;
+                default:
+                        show_usage();
+                        break;
+                }
+        }
+
+        if (argc - optind > 0) {
+                if (do_all) {
+                        show_usage();
+                }
+        } else {
+                if (!do_all) {
+                        show_usage();
+                }
+        }                       
+
+        defn = read_interfaces(interfaces);
+        if (!defn) {
+                error_msg_and_die("couldn't read interfaces file \"%s\"", interfaces);
+        }
+
+        state_fp = fopen(statefile, no_act ? "r" : "a+");
+        if (state_fp == NULL && !no_act) {
+                perror_msg_and_die("failed to open statefile %s", statefile);
+        }
+
+        if (state_fp != NULL) {
+                char buf[80];
+                char *p;
+
+                if (!no_act) {
+                        int flags;
+                        struct flock lock;
+                        const int state_fd = fileno(state_fp);
+                        
+                        flags = fcntl(state_fd, F_GETFD);
+                        if ((flags < 0) || (fcntl(state_fd, F_SETFD, flags | FD_CLOEXEC) < 0)) {
+                                perror_msg_and_die("failed to set FD_CLOEXEC on statefile %s", statefile);
+                        }
+
+                        lock.l_type = F_WRLCK;
+                        lock.l_whence = SEEK_SET;
+                        lock.l_start = 0;
+                        lock.l_len = 0;
+
+                        if (fcntl(state_fd, F_SETLKW, &lock) < 0) {
+                                perror_msg_and_die("failed to lock statefile %s", statefile);
+                        }
+                }
+
+                rewind(state_fp);
+                while ((p = fgets(buf, sizeof buf, state_fp)) != NULL) {
+                        char *pch;
+
+                        pch = buf + xstrlen(buf) - 1;
+                        while (pch > buf && isspace(*pch)) {
+                                pch--;
+                        }
+                        *(pch + 1) = '\0';
+
+                        pch = buf;
+                        while (isspace(*pch)) {
+                                pch++;
+                        }
+
+                        add_to_state(&state, &n_state, &max_state, xstrdup(pch));
+                }
+        }
+
+        if (do_all) {
+                if (cmds == iface_up) {
+                        target_iface = defn->autointerfaces;
+                        n_target_ifaces = defn->n_autointerfaces;
+                } else if (cmds == iface_down) {
+                        target_iface = state;
+                        n_target_ifaces = n_state;
+                }
+        } else {
+                target_iface = argv + optind;
+                n_target_ifaces = argc - optind;
+        }
+
+
+        for (i = 0; i < n_target_ifaces; i++) {
+                interface_defn *currif;
+                char iface[80];
+                char liface[80];
+                char *pch;
+                int okay = 0;
+
+                strncpy(iface, target_iface[i], sizeof(iface));
+                iface[sizeof(iface) - 1] = '\0';
+
+                if ((pch = strchr(iface, '='))) {
+                        *pch = '\0';
+                        strncpy(liface, pch + 1, sizeof(liface));
+                        liface[sizeof(liface) - 1] = '\0';
+                } else {
+                        strncpy(liface, iface, sizeof(liface));
+                        liface[sizeof(liface) - 1] = '\0';
+                }
+                if (!force) {
+                        int already_up = lookfor_iface(state, n_state, iface);;
+
+                        if (cmds == iface_up) {
+                                /* ifup */
+                                if (already_up != -1) {
+                                        error_msg("interface %s already configured", iface);
+                                        continue;
+                                }
+                        } else {
+                                /* ifdown */
+                                if (already_up == -1) {
+                                        error_msg("interface %s not configured", iface);
+                                        continue;
+                                }
+                                strncpy(liface, strchr(state[already_up], '=') + 1, 80);
+                                liface[79] = 0;
+                        }
+                }
+
+                if ((cmds == iface_up) && run_mappings) {
+                        mapping_defn *currmap;
+
+                        for (currmap = defn->mappings; currmap; currmap = currmap->next) {
+
+                                for (i = 0; i < currmap->n_matches; i++) {
+                                        if (fnmatch(currmap->match[i], liface, 0) != 0)
+                                                continue;
+                                        if (verbose) {
+                                                error_msg("Running mapping script %s on %s", currmap->script, liface);
+                                        }
+                                        run_mapping(iface, liface, sizeof(liface), currmap);
+                                        break;
+                                }
+                        }
+                }
+
+
+                for (currif = defn->ifaces; currif; currif = currif->next) {
+                        if (strcmp(liface, currif->iface) == 0) {
+                                char *oldiface = currif->iface;
+
+                                okay = 1;
+
+                                currif->iface = iface;
+
+                                if (verbose) {
+                                        error_msg("Configuring interface %s=%s (%s)", iface, liface, currif->address_family->name);
+                                }
+
+                                switch (cmds(currif)) {
+                                case -1:
+                                        printf
+                                                ("Don't seem to be have all the variables for %s/%s.\n",
+                                                 liface, currif->address_family->name);
+                                        break;
+                                case 0:
+                                        /* this wasn't entirely successful, should it be added to
+                                         *      the state file?
+                                         */
+                                case 1:
+                                        /* successful */
+                                }
+                                currif->iface = oldiface;
+                        }
+                }
+
+                if (!okay && !force) {
+                        error_msg("Ignoring unknown interface %s=%s.", iface, liface);
+                } else {
+                        int already_up = lookfor_iface(state, n_state, iface);
+
+                        if (cmds == iface_up) {
+                                char *newiface = xmalloc(xstrlen(iface) + 1 + xstrlen(liface) + 1);
+                                sprintf(newiface, "%s=%s", iface, liface);
+                                if (already_up == -1) {
+                                        add_to_state(&state, &n_state, &max_state, newiface);
+                                } else {
+                                        free(state[already_up]);
+                                        state[already_up] = newiface;
+                                }
+                        } else if (cmds == iface_down) {
+                                if (already_up != -1) {
+                                        state[already_up] = state[--n_state];
+                                }
+                        }
+                }
+                if (state_fp != NULL && !no_act) {
+                        if (ftruncate(fileno(state_fp), 0) < 0) {
+                                error_msg_and_die("failed to truncate statefile %s: %s", statefile, strerror(errno));
+                        }
+
+                        rewind(state_fp);
+                        for (i = 0; i < n_state; i++) {
+                                fputs(state[i], state_fp);
+                                fputc('\n', state_fp);
+                        }
+                        fflush(state_fp);
+                }
+        }
+
+        if (state_fp != NULL) {
+                fclose(state_fp);
+                state_fp = NULL;
+        }
+
+        return 0;
+}