busybox/networking/ifupdown.c
Denis Vlasenko 06b543b217 ifupdown: make dhcp start/stop scripts user configurable
in /etc/network/interfaces. Patch author is Gabriel L. Somlo <somlo@cmu.edu>
2006-09-28 22:31:51 +00:00

1249 lines
30 KiB
C

/* vi: set sw=4 ts=4: */
/*
* ifupdown for busybox
* Copyright (c) 2002 Glenn McGrath <bug1@iinet.net.au>
* Copyright (c) 2003-2004 Erik Andersen <andersen@codepoet.org>
*
* Based on ifupdown v 0.6.4 by Anthony Towns
* Copyright (c) 1999 Anthony Towns <aj@azure.humbug.org.au>
*
* Changes to upstream version
* Remove checks for kernel version, assume kernel version 2.2.0 or better.
* Lines in the interfaces file cannot wrap.
* To adhere to the FHS, the default state file is /var/run/ifstate.
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include "busybox.h"
#include <sys/utsname.h>
#include <fnmatch.h>
#include <getopt.h>
#define MAX_OPT_DEPTH 10
#define EUNBALBRACK 10001
#define EUNDEFVAR 10002
#define EUNBALPER 10000
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
#define MAX_INTERFACE_LENGTH 10
#endif
#define debug_noise(fmt, args...)
/* Forward declaration */
struct interface_defn_t;
typedef int (execfn)(char *command);
struct method_t
{
char *name;
int (*up)(struct interface_defn_t *ifd, execfn *e);
int (*down)(struct interface_defn_t *ifd, execfn *e);
};
struct address_family_t
{
char *name;
int n_methods;
const struct method_t *method;
};
struct mapping_defn_t
{
struct mapping_defn_t *next;
int max_matches;
int n_matches;
char **match;
char *script;
int max_mappings;
int n_mappings;
char **mapping;
};
struct variable_t
{
char *name;
char *value;
};
struct interface_defn_t
{
const struct address_family_t *address_family;
const struct method_t *method;
char *iface;
int max_options;
int n_options;
struct variable_t *option;
};
struct interfaces_file_t
{
llist_t *autointerfaces;
llist_t *ifaces;
struct mapping_defn_t *mappings;
};
static unsigned option_mask;
#define OPTION_STR "anvf" USE_FEATURE_IFUPDOWN_MAPPING("m") "i:"
enum {
OPT_do_all = 0x1,
OPT_no_act = 0x2,
OPT_verbose = 0x4,
OPT_force = 0x8,
OPT_no_mappings = 0x10,
};
#define DO_ALL (option_mask & OPT_do_all)
#define NO_ACT (option_mask & OPT_no_act)
#define VERBOSE (option_mask & OPT_verbose)
#define FORCE (option_mask & OPT_force)
#define NO_MAPPINGS (option_mask & OPT_no_mappings)
static char **__myenviron;
static char *startup_PATH;
#if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
static unsigned int count_bits(unsigned int a)
{
unsigned int result;
result = (a & 0x55) + ((a >> 1) & 0x55);
result = (result & 0x33) + ((result >> 2) & 0x33);
return ((result & 0x0F) + ((result >> 4) & 0x0F));
}
static int count_netmask_bits(char *dotted_quad)
{
unsigned int result, a, b, c, d;
/* Found a netmask... Check if it is dotted quad */
if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
return -1;
result = count_bits(a);
result += count_bits(b);
result += count_bits(c);
result += count_bits(d);
return (int)result;
}
#endif
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, struct interface_defn_t *ifd)
{
int i;
if (strncmpz(id, "iface", idlen) == 0) {
char *result;
static char label_buf[20];
strncpy(label_buf, ifd->iface, 19);
label_buf[19]=0;
result = strchr(label_buf, ':');
if (result) {
*result=0;
}
return label_buf;
} else if (strncmpz(id, "label", 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, struct interface_defn_t *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, strlen(varvalue));
} else {
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
/* Sigh... Add a special case for 'ip' to convert from
* dotted quad to bit count style netmasks. */
if (strncmp(command, "bnmask", 6)==0) {
int res;
varvalue = get_var("netmask", 7, ifd);
if (varvalue && (res=count_netmask_bits(varvalue)) > 0) {
char argument[255];
sprintf(argument, "%d", res);
addstr(&result, &len, &pos, argument, strlen(argument));
command = nextpercent + 1;
break;
}
}
#endif
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;
}
/* execute() returns 1 for success and 0 for failure */
static int execute(char *command, struct interface_defn_t *ifd, execfn *exec)
{
char *out;
int ret;
out = parse(command, ifd);
if (!out) {
return 0;
}
ret = (*exec)(out);
free(out);
if (ret != 1) {
return 0;
}
return 1;
}
#endif
#ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
static int loopback_up6(struct interface_defn_t *ifd, execfn *exec)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
int result;
result = execute("ip addr add ::1 dev %iface%", ifd, exec);
result += execute("ip link set %iface% up", ifd, exec);
return ((result == 2) ? 2 : 0);
#else
return execute("ifconfig %iface% add ::1", ifd, exec);
#endif
}
static int loopback_down6(struct interface_defn_t *ifd, execfn *exec)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
return execute("ip link set %iface% down", ifd, exec);
#else
return execute("ifconfig %iface% del ::1", ifd, exec);
#endif
}
static int static_up6(struct interface_defn_t *ifd, execfn *exec)
{
int result;
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
result = execute("ip addr add %address%/%netmask% dev %iface% [[label %label%]]", ifd, exec);
result += execute("ip link set [[mtu %mtu%]] [[address %hwaddress%]] %iface% up", ifd, exec);
result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
#else
result = execute("ifconfig %iface% [[media %media%]] [[hw %hwaddress%]] [[mtu %mtu%]] up", ifd, exec);
result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
result += execute("[[ route -A inet6 add ::/0 gw %gateway% ]]", ifd, exec);
#endif
return ((result == 3) ? 3 : 0);
}
static int static_down6(struct interface_defn_t *ifd, execfn *exec)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
return execute("ip link set %iface% down", ifd, exec);
#else
return execute("ifconfig %iface% down", ifd, exec);
#endif
}
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
static int v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
{
int result;
result = execute("ip tunnel add %iface% mode sit remote "
"%endpoint% [[local %local%]] [[ttl %ttl%]]", ifd, exec);
result += execute("ip link set %iface% up", ifd, exec);
result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
return ((result == 4) ? 4 : 0);
}
static int v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
{
return execute("ip tunnel del %iface%", ifd, exec);
}
#endif
static const struct method_t methods6[] = {
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
{ "v4tunnel", v4tunnel_up, v4tunnel_down, },
#endif
{ "static", static_up6, static_down6, },
{ "loopback", loopback_up6, loopback_down6, },
};
static const struct address_family_t addr_inet6 = {
"inet6",
sizeof(methods6) / sizeof(struct method_t),
methods6
};
#endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
#ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
static int loopback_up(struct interface_defn_t *ifd, execfn *exec)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
int result;
result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
result += execute("ip link set %iface% up", ifd, exec);
return ((result == 2) ? 2 : 0);
#else
return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
#endif
}
static int loopback_down(struct interface_defn_t *ifd, execfn *exec)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
int result;
result = execute("ip addr flush dev %iface%", ifd, exec);
result += execute("ip link set %iface% down", ifd, exec);
return ((result == 2) ? 2 : 0);
#else
return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
#endif
}
static int static_up(struct interface_defn_t *ifd, execfn *exec)
{
int result;
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
result = execute("ip addr add %address%/%bnmask% [[broadcast %broadcast%]] "
"dev %iface% [[peer %pointopoint%]] [[label %label%]]", ifd, exec);
result += execute("ip link set [[mtu %mtu%]] [[address %hwaddress%]] %iface% up", ifd, exec);
result += execute("[[ ip route add default via %gateway% dev %iface% ]]", ifd, exec);
return ((result == 3) ? 3 : 0);
#else
result = execute("ifconfig %iface% %address% netmask %netmask% "
"[[broadcast %broadcast%]] [[pointopoint %pointopoint%]] "
"[[media %media%]] [[mtu %mtu%]] [[hw %hwaddress%]] up",
ifd, exec);
result += execute("[[ route add default gw %gateway% %iface% ]]", ifd, exec);
return ((result == 2) ? 2 : 0);
#endif
}
static int static_down(struct interface_defn_t *ifd, execfn *exec)
{
int result;
#ifdef CONFIG_FEATURE_IFUPDOWN_IP
result = execute("ip addr flush dev %iface%", ifd, exec);
result += execute("ip link set %iface% down", ifd, exec);
#else
result = execute("[[ route del default gw %gateway% %iface% ]]", ifd, exec);
result += execute("ifconfig %iface% down", ifd, exec);
#endif
return ((result == 2) ? 2 : 0);
}
static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
{
int i;
for (i = 0; i < ifd->n_options; i++) {
if (strcmp(ifd->option[i].name, "dhcp-start-cmd") == 0) {
return execute(ifd->option[i].value, ifd, exec);
}
}
if (execute("udhcpc -n -p /var/run/udhcpc.%iface%.pid -i "
"%iface% [[-H %hostname%]] [[-c %clientid%]]", ifd, exec)) return 1;
if (execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]", ifd, exec)) return 1;
if (execute("dhclient -pf /var/run/dhclient.%iface%.pid %iface%", ifd, exec)) return 1;
if (execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] "
"[[-l %leasetime%]] %iface%", ifd, exec)) return 1;
return 0;
}
static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
{
int i;
for (i = 0; i < ifd->n_options; i++) {
if (strcmp(ifd->option[i].name, "dhcp-stop-cmd") == 0) {
return execute(ifd->option[i].value, ifd, exec);
}
}
/* SIGUSR2 forces udhcpc to release the current lease and go inactive,
* and SIGTERM causes udhcpc to exit. Signals are queued and processed
* sequentially so we don't need to sleep */
if (execute("kill -USR2 `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec)
|| execute("kill -TERM `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec))
return 1;
if (execute("pump -i %iface% -k", ifd, exec)) return 1;
if (execute("kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null", ifd, exec)) return 1;
if (execute("dhcpcd -k %iface%", ifd, exec)) return 1;
return static_down(ifd, exec);
}
static int bootp_up(struct interface_defn_t *ifd, execfn *exec)
{
return execute("bootpc [[--bootfile %bootfile%]] --dev %iface% "
"[[--server %server%]] [[--hwaddr %hwaddr%]] "
"--returniffail --serverbcast", ifd, exec);
}
static int ppp_up(struct interface_defn_t *ifd, execfn *exec)
{
return execute("pon [[%provider%]]", ifd, exec);
}
static int ppp_down(struct interface_defn_t *ifd, execfn *exec)
{
return execute("poff [[%provider%]]", ifd, exec);
}
static int wvdial_up(struct interface_defn_t *ifd, execfn *exec)
{
return execute("/sbin/start-stop-daemon --start -x /usr/bin/wvdial "
"-p /var/run/wvdial.%iface% -b -m -- [[ %provider% ]]", ifd, exec);
}
static int wvdial_down(struct interface_defn_t *ifd, execfn *exec)
{
return execute("/sbin/start-stop-daemon --stop -x /usr/bin/wvdial "
"-p /var/run/wvdial.%iface% -s 2", ifd, exec);
}
static const struct method_t methods[] = {
{ "wvdial", wvdial_up, wvdial_down, },
{ "ppp", ppp_up, ppp_down, },
{ "static", static_up, static_down, },
{ "bootp", bootp_up, static_down, },
{ "dhcp", dhcp_up, dhcp_down, },
{ "loopback", loopback_up, loopback_down, },
};
static const struct address_family_t addr_inet = {
"inet",
sizeof(methods) / sizeof(struct method_t),
methods
};
#endif /* ifdef CONFIG_FEATURE_IFUPDOWN_IPV4 */
static char *next_word(char **buf)
{
unsigned short length;
char *word;
if ((buf == NULL) || (*buf == NULL) || (**buf == '\0')) {
return NULL;
}
/* Skip over leading whitespace */
word = *buf;
while (isspace(*word)) {
++word;
}
/* Skip over comments */
if (*word == '#') {
return NULL;
}
/* Find the length of this word */
length = strcspn(word, " \t\n");
if (length == 0) {
return NULL;
}
*buf = word + length;
/*DBU:[dave@cray.com] if we are already at EOL dont't increment beyond it */
if (**buf) {
**buf = '\0';
(*buf)++;
}
return word;
}
static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
{
int i;
for (i = 0; af[i]; i++) {
if (strcmp(af[i]->name, name) == 0) {
return af[i];
}
}
return NULL;
}
static const struct method_t *get_method(const struct address_family_t *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 const llist_t *find_list_string(const llist_t *list, const char *string)
{
while (list) {
if (strcmp(list->data, string) == 0) {
return list;
}
list = list->link;
}
return NULL;
}
static struct interfaces_file_t *read_interfaces(const char *filename)
{
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
struct mapping_defn_t *currmap = NULL;
#endif
struct interface_defn_t *currif = NULL;
struct interfaces_file_t *defn;
FILE *f;
char *firstword;
char *buf;
enum { NONE, IFACE, MAPPING } currently_processing = NONE;
defn = xzalloc(sizeof(struct interfaces_file_t));
f = xfopen(filename, "r");
while ((buf = bb_get_chomped_line_from_file(f)) != NULL) {
char *buf_ptr = buf;
firstword = next_word(&buf_ptr);
if (firstword == NULL) {
free(buf);
continue; /* blank line */
}
if (strcmp(firstword, "mapping") == 0) {
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
currmap = xzalloc(sizeof(struct mapping_defn_t));
while ((firstword = next_word(&buf_ptr)) != NULL) {
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;
{
struct mapping_defn_t **where = &defn->mappings;
while (*where != NULL) {
where = &(*where)->next;
}
*where = currmap;
currmap->next = NULL;
}
debug_noise("Added mapping\n");
#endif
currently_processing = MAPPING;
} else if (strcmp(firstword, "iface") == 0) {
static const struct address_family_t *const addr_fams[] = {
#ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
&addr_inet,
#endif
#ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
&addr_inet6,
#endif
NULL
};
char *iface_name;
char *address_family_name;
char *method_name;
llist_t *iface_list;
currif = xzalloc(sizeof(struct interface_defn_t));
iface_name = next_word(&buf_ptr);
address_family_name = next_word(&buf_ptr);
method_name = next_word(&buf_ptr);
if (buf_ptr == NULL) {
bb_error_msg("too few parameters for line \"%s\"", buf);
return NULL;
}
/* ship any trailing whitespace */
while (isspace(*buf_ptr)) {
++buf_ptr;
}
if (buf_ptr[0] != '\0') {
bb_error_msg("too many parameters \"%s\"", buf);
return NULL;
}
currif->iface = xstrdup(iface_name);
currif->address_family = get_address_family(addr_fams, address_family_name);
if (!currif->address_family) {
bb_error_msg("unknown address type \"%s\"", address_family_name);
return NULL;
}
currif->method = get_method(currif->address_family, method_name);
if (!currif->method) {
bb_error_msg("unknown method \"%s\"", method_name);
return NULL;
}
for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
if ((strcmp(tmp->iface, currif->iface) == 0) &&
(tmp->address_family == currif->address_family)) {
bb_error_msg("duplicate interface \"%s\"", tmp->iface);
return NULL;
}
}
llist_add_to_end(&(defn->ifaces), (char*)currif);
debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
currently_processing = IFACE;
} else if (strcmp(firstword, "auto") == 0) {
while ((firstword = next_word(&buf_ptr)) != NULL) {
/* Check the interface isnt already listed */
if (find_list_string(defn->autointerfaces, firstword)) {
bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
}
/* Add the interface to the list */
llist_add_to_end(&(defn->autointerfaces), xstrdup(firstword));
debug_noise("\nauto %s\n", firstword);
}
currently_processing = NONE;
} else {
switch (currently_processing) {
case IFACE:
{
int i;
if (strlen(buf_ptr) == 0) {
bb_error_msg("option with empty value \"%s\"", buf);
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) {
bb_error_msg("duplicate option \"%s\"", buf);
return NULL;
}
}
}
}
if (currif->n_options >= currif->max_options) {
struct variable_t *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(buf_ptr);
if (!currif->option[currif->n_options].name) {
perror(filename);
return NULL;
}
if (!currif->option[currif->n_options].value) {
perror(filename);
return NULL;
}
debug_noise("\t%s=%s\n", currif->option[currif->n_options].name,
currif->option[currif->n_options].value);
currif->n_options++;
break;
case MAPPING:
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
if (strcmp(firstword, "script") == 0) {
if (currmap->script != NULL) {
bb_error_msg("duplicate script in mapping \"%s\"", buf);
return NULL;
} else {
currmap->script = xstrdup(next_word(&buf_ptr));
}
} 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(next_word(&buf_ptr));
currmap->n_mappings++;
} else {
bb_error_msg("misplaced option \"%s\"", buf);
return NULL;
}
#endif
break;
case NONE:
default:
bb_error_msg("misplaced option \"%s\"", buf);
return NULL;
}
}
free(buf);
}
if (ferror(f) != 0) {
bb_perror_msg_and_die("%s", filename);
}
fclose(f);
return defn;
}
static char *setlocalenv(char *format, const char *name, const char *value)
{
char *result;
char *here;
char *there;
result = xasprintf(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, strlen(there) + 1);
return result;
}
static void set_environ(struct interface_defn_t *iface, const char *mode)
{
char **environend;
int i;
const int n_env_entries = iface->n_options + 5;
char **ppch;
if (__myenviron != NULL) {
for (ppch = __myenviron; *ppch; ppch++) {
free(*ppch);
*ppch = NULL;
}
free(__myenviron);
}
__myenviron = xzalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
environend = __myenviron;
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++) = setlocalenv("%s=%s", "IFACE", iface->iface);
*(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
*(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
*(environend++) = setlocalenv("%s=%s", "MODE", mode);
*(environend++) = setlocalenv("%s=%s", "PATH", startup_PATH);
}
static int doit(char *str)
{
if (option_mask & (OPT_no_act|OPT_verbose)) {
puts(str);
}
if (!(option_mask & OPT_no_act)) {
pid_t child;
int status;
fflush(NULL);
switch (child = fork()) {
case -1: /* failure */
return 0;
case 0: /* child */
execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, NULL, __myenviron);
exit(127);
}
waitpid(child, &status, 0);
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
return 0;
}
}
return 1;
}
static int execute_all(struct interface_defn_t *ifd, const char *opt)
{
int i;
char *buf;
for (i = 0; i < ifd->n_options; i++) {
if (strcmp(ifd->option[i].name, opt) == 0) {
if (!doit(ifd->option[i].value)) {
return 0;
}
}
}
buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
if (doit(buf) != 1) {
return 0;
}
return 1;
}
static int check(char *str) {
return str != NULL;
}
static int iface_up(struct interface_defn_t *iface)
{
if (!iface->method->up(iface,check)) return -1;
set_environ(iface, "start");
if (!execute_all(iface, "pre-up")) return 0;
if (!iface->method->up(iface, doit)) return 0;
if (!execute_all(iface, "up")) return 0;
return 1;
}
static int iface_down(struct interface_defn_t *iface)
{
if (!iface->method->down(iface,check)) return -1;
set_environ(iface, "stop");
if (!execute_all(iface, "down")) return 0;
if (!iface->method->down(iface, doit)) return 0;
if (!execute_all(iface, "post-down")) return 0;
return 1;
}
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
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 char *run_mapping(char *physical, struct mapping_defn_t * map)
{
FILE *in, *out;
int i, status;
pid_t pid;
char *logical = xstrdup(physical);
/* Run the mapping script. */
pid = popen2(&in, &out, map->script, physical, NULL);
/* popen2() returns 0 on failure. */
if (pid == 0)
return logical;
/* Write mappings to stdin of mapping script. */
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 the mapping script exited successfully, try to
* grab a line of output and use that as the name of the
* logical interface. */
char *new_logical = (char *)xmalloc(MAX_INTERFACE_LENGTH);
if (fgets(new_logical, MAX_INTERFACE_LENGTH, out)) {
/* If we are able to read a line of output from the script,
* remove any trailing whitespace and use this value
* as the name of the logical interface. */
char *pch = new_logical + strlen(new_logical) - 1;
while (pch >= new_logical && isspace(*pch))
*(pch--) = '\0';
free(logical);
logical = new_logical;
} else {
/* If we are UNABLE to read a line of output, discard our
* freshly allocated memory. */
free(new_logical);
}
}
fclose(out);
return logical;
}
#endif /* CONFIG_FEATURE_IFUPDOWN_MAPPING */
static llist_t *find_iface_state(llist_t *state_list, const char *iface)
{
unsigned short iface_len = strlen(iface);
llist_t *search = state_list;
while (search) {
if ((strncmp(search->data, iface, iface_len) == 0) &&
(search->data[iface_len] == '=')) {
return search;
}
search = search->link;
}
return NULL;
}
int ifupdown_main(int argc, char **argv)
{
static const char statefile[] = "/var/run/ifstate";
int (*cmds)(struct interface_defn_t *) = NULL;
struct interfaces_file_t *defn;
llist_t *state_list = NULL;
llist_t *target_list = NULL;
const char *interfaces = "/etc/network/interfaces";
int any_failures = 0;
int i;
if (bb_applet_name[2] == 'u') {
/* ifup command */
cmds = iface_up;
} else {
/* ifdown command */
cmds = iface_down;
}
option_mask = bb_getopt_ulflags(argc, argv, OPTION_STR, &interfaces);
if (argc - optind > 0) {
if (DO_ALL) bb_show_usage();
} else
if (!DO_ALL) bb_show_usage();
debug_noise("reading %s file:\n", interfaces);
defn = read_interfaces(interfaces);
debug_noise("\ndone reading %s\n\n", interfaces);
if (!defn) {
exit(EXIT_FAILURE);
}
startup_PATH = getenv("PATH");
if (!startup_PATH) startup_PATH = "";
/* Create a list of interfaces to work on */
if (DO_ALL) {
if (cmds == iface_up) {
target_list = defn->autointerfaces;
} else {
/* iface_down */
const llist_t *list = state_list;
while (list) {
llist_add_to_end(&target_list, xstrdup(list->data));
list = list->link;
}
target_list = defn->autointerfaces;
}
} else {
llist_add_to_end(&target_list, argv[optind]);
}
/* Update the interfaces */
while (target_list) {
llist_t *iface_list;
struct interface_defn_t *currif;
char *iface;
char *liface;
char *pch;
int okay = 0;
int cmds_ret;
iface = xstrdup(target_list->data);
target_list = target_list->link;
pch = strchr(iface, '=');
if (pch) {
*pch = '\0';
liface = xstrdup(pch + 1);
} else {
liface = xstrdup(iface);
}
if (!FORCE) {
const llist_t *iface_state = find_iface_state(state_list, iface);
if (cmds == iface_up) {
/* ifup */
if (iface_state) {
bb_error_msg("interface %s already configured", iface);
continue;
}
} else {
/* ifdown */
if (iface_state) {
bb_error_msg("interface %s not configured", iface);
continue;
}
}
}
#ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
if ((cmds == iface_up) && !NO_MAPPINGS) {
struct mapping_defn_t *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) {
printf("Running mapping script %s on %s\n", currmap->script, liface);
}
liface = run_mapping(iface, currmap);
break;
}
}
}
#endif
iface_list = defn->ifaces;
while (iface_list) {
currif = (struct interface_defn_t *) iface_list->data;
if (strcmp(liface, currif->iface) == 0) {
char *oldiface = currif->iface;
okay = 1;
currif->iface = iface;
debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
/* Call the cmds function pointer, does either iface_up() or iface_down() */
cmds_ret = cmds(currif);
if (cmds_ret == -1) {
bb_error_msg("don't seem to have all the variables for %s/%s",
liface, currif->address_family->name);
any_failures += 1;
} else if (cmds_ret == 0) {
any_failures += 1;
}
currif->iface = oldiface;
}
iface_list = iface_list->link;
}
if (VERBOSE) {
puts("");
}
if (!okay && !FORCE) {
bb_error_msg("ignoring unknown interface %s", liface);
any_failures += 1;
} else {
llist_t *iface_state = find_iface_state(state_list, iface);
if (cmds == iface_up) {
char *newiface = xasprintf("%s=%s", iface, liface);
if (iface_state == NULL) {
llist_add_to_end(&state_list, newiface);
} else {
free(iface_state->data);
iface_state->data = newiface;
}
} else {
/* Remove an interface from the linked list */
free(llist_pop(&iface_state));
}
}
}
/* Actually write the new state */
if (!NO_ACT) {
FILE *state_fp = NULL;
state_fp = xfopen(statefile, "w");
while (state_list) {
if (state_list->data) {
fputs(state_list->data, state_fp);
fputc('\n', state_fp);
}
state_list = state_list->link;
}
fclose(state_fp);
}
if (any_failures)
return 1;
return 0;
}