hush/networking/ifupdown.c
Natanael Copa cfcb1dac83 ifupdown: support metric for static default gw
This is useful when you have multiple ISPs with failover. It allows
setting the priority of the static gateway and makes it possible
to specify multiple static gateways.

The ubuntu ifupdown supports it.

function                                             old     new   delta
.rodata                                           116725  116797     +72
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 72/0)               Total: 72 bytes
   text    data     bss     dec     hex filename
 953343    7313    8984  969640   ecba8 busybox_old
 953415    7313    8984  969712   ecbf0 busybox_unstripped

Signed-off-by: Natanael Copa <natanael.copa@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2012-02-19 17:25:55 +01:00

1347 lines
35 KiB
C

/* vi: set sw=4 ts=4: */
/*
* ifupdown for busybox
* Copyright (c) 2002 Glenn McGrath
* 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
* (defined via CONFIG_IFUPDOWN_IFSTATE_PATH) and can be overridden by build
* configuration.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//usage:#define ifup_trivial_usage
//usage: "[-an"IF_FEATURE_IFUPDOWN_MAPPING("m")"vf] [-i FILE] IFACE..."
//usage:#define ifup_full_usage "\n\n"
//usage: " -a De/configure all interfaces automatically"
//usage: "\n -i FILE Use FILE for interface definitions"
//usage: "\n -n Print out what would happen, but don't do it"
//usage: IF_FEATURE_IFUPDOWN_MAPPING(
//usage: "\n (note: doesn't disable mappings)"
//usage: "\n -m Don't run any mappings"
//usage: )
//usage: "\n -v Print out what would happen before doing it"
//usage: "\n -f Force de/configuration"
//usage:
//usage:#define ifdown_trivial_usage
//usage: "[-an"IF_FEATURE_IFUPDOWN_MAPPING("m")"vf] [-i FILE] IFACE..."
//usage:#define ifdown_full_usage "\n\n"
//usage: " -a De/configure all interfaces automatically"
//usage: "\n -i FILE Use FILE for interface definitions"
//usage: "\n -n Print out what would happen, but don't do it"
//usage: IF_FEATURE_IFUPDOWN_MAPPING(
//usage: "\n (note: doesn't disable mappings)"
//usage: "\n -m Don't run any mappings"
//usage: )
//usage: "\n -v Print out what would happen before doing it"
//usage: "\n -f Force de/configuration"
#include "libbb.h"
/* After libbb.h, since it needs sys/types.h on some systems */
#include <sys/utsname.h>
#include <fnmatch.h>
#define MAX_OPT_DEPTH 10
#define EUNBALBRACK 10001
#define EUNDEFVAR 10002
#define EUNBALPER 10000
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
#define MAX_INTERFACE_LENGTH 10
#endif
#define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
#define debug_noise(args...) /*fprintf(stderr, args)*/
/* Forward declaration */
struct interface_defn_t;
typedef int execfn(char *command);
struct method_t {
const char *name;
int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
};
struct address_family_t {
const 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 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 n_options;
struct variable_t *option;
};
struct interfaces_file_t {
llist_t *autointerfaces;
llist_t *ifaces;
struct mapping_defn_t *mappings;
};
#define OPTION_STR "anvf" IF_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_mask32 & OPT_do_all)
#define NO_ACT (option_mask32 & OPT_no_act)
#define VERBOSE (option_mask32 & OPT_verbose)
#define FORCE (option_mask32 & OPT_force)
#define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
struct globals {
char **my_environ;
const char *startup_PATH;
char *shell;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
static const char keywords_up_down[] ALIGN1 =
"up\0"
"down\0"
"pre-up\0"
"pre-down\0"
"post-up\0"
"post-down\0"
;
#if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
static void addstr(char **bufp, const char *str, size_t str_length)
{
/* xasprintf trick will be smaller, but we are often
* called with str_length == 1 - don't want to have
* THAT much of malloc/freeing! */
char *buf = *bufp;
int len = (buf ? strlen(buf) : 0);
str_length++;
buf = xrealloc(buf, len + str_length);
/* copies at most str_length-1 chars! */
safe_strncpy(buf + len, str, str_length);
*bufp = buf;
}
static int strncmpz(const char *l, const char *r, size_t llen)
{
int i = strncmp(l, r, llen);
if (i == 0)
return - (unsigned char)r[llen];
return i;
}
static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
{
int i;
if (strncmpz(id, "iface", idlen) == 0) {
// ubuntu's ifup doesn't do this:
//static char *label_buf;
//char *result;
//free(label_buf);
//label_buf = xstrdup(ifd->iface);
// Remove virtual iface suffix
//result = strchrnul(label_buf, ':');
//*result = '\0';
//return label_buf;
return ifd->iface;
}
if (strncmpz(id, "label", idlen) == 0) {
return ifd->iface;
}
for (i = 0; i < ifd->n_options; i++) {
if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
return ifd->option[i].value;
}
}
return NULL;
}
# if ENABLE_FEATURE_IFUPDOWN_IP
static int count_netmask_bits(const char *dotted_quad)
{
// int result;
// unsigned 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;
// if ((a|b|c|d) >> 8)
// return -1; /* one of numbers is >= 256 */
// d |= (a << 24) | (b << 16) | (c << 8); /* IP */
// d = ~d; /* 11110000 -> 00001111 */
/* Shorter version */
int result;
struct in_addr ip;
unsigned d;
if (inet_aton(dotted_quad, &ip) == 0)
return -1; /* malformed dotted IP */
d = ntohl(ip.s_addr); /* IP in host order */
d = ~d; /* 11110000 -> 00001111 */
if (d & (d+1)) /* check that it is in 00001111 form */
return -1; /* no it is not */
result = 32;
while (d) {
d >>= 1;
result--;
}
return result;
}
# endif
static char *parse(const char *command, struct interface_defn_t *ifd)
{
size_t old_pos[MAX_OPT_DEPTH] = { 0 };
int okay[MAX_OPT_DEPTH] = { 1 };
int opt_depth = 1;
char *result = NULL;
while (*command) {
switch (*command) {
default:
addstr(&result, command, 1);
command++;
break;
case '\\':
if (command[1]) {
addstr(&result, command + 1, 1);
command += 2;
} else {
addstr(&result, command, 1);
command++;
}
break;
case '[':
if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
old_pos[opt_depth] = result ? strlen(result) : 0;
okay[opt_depth] = 1;
opt_depth++;
command += 2;
} else {
addstr(&result, "[", 1);
command++;
}
break;
case ']':
if (command[1] == ']' && opt_depth > 1) {
opt_depth--;
if (!okay[opt_depth]) {
result[old_pos[opt_depth]] = '\0';
}
command += 2;
} else {
addstr(&result, "]", 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) {
# if ENABLE_FEATURE_IFUPDOWN_IP
/* "hwaddress <class> <address>":
* unlike ifconfig, ip doesnt want <class>
* (usually "ether" keyword). Skip it. */
if (strncmp(command, "hwaddress", 9) == 0) {
varvalue = skip_whitespace(skip_non_whitespace(varvalue));
}
# endif
addstr(&result, varvalue, strlen(varvalue));
} else {
# if ENABLE_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) {
unsigned res;
varvalue = get_var("netmask", 7, ifd);
if (varvalue) {
res = count_netmask_bits(varvalue);
if (res > 0) {
const char *argument = utoa(res);
addstr(&result, 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(const char *command, struct interface_defn_t *ifd, execfn *exec)
{
char *out;
int ret;
out = parse(command, ifd);
if (!out) {
/* parse error? */
return 0;
}
/* out == "": parsed ok but not all needed variables known, skip */
ret = out[0] ? (*exec)(out) : 1;
free(out);
if (ret != 1) {
return 0;
}
return 1;
}
#endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
#if ENABLE_FEATURE_IFUPDOWN_IPV6
static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_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 FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_FEATURE_IFUPDOWN_IP
return execute("ip link set %iface% down", ifd, exec);
# else
return execute("ifconfig %iface% del ::1", ifd, exec);
# endif
}
static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
{
return 1;
}
static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
{
int result;
# if ENABLE_FEATURE_IFUPDOWN_IP
result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
/* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
result += execute("[[ip route add ::/0 via %gateway%]][[ prio %metric%]]", 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%[[ metric %metric%]]]]", ifd, exec);
# endif
return ((result == 3) ? 3 : 0);
}
static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_FEATURE_IFUPDOWN_IP
return execute("ip link set %iface% down", ifd, exec);
# else
return execute("ifconfig %iface% down", ifd, exec);
# endif
}
# if ENABLE_FEATURE_IFUPDOWN_IP
static int FAST_FUNC 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 FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
{
return execute("ip tunnel del %iface%", ifd, exec);
}
# endif
static const struct method_t methods6[] = {
# if ENABLE_FEATURE_IFUPDOWN_IP
{ "v4tunnel" , v4tunnel_up , v4tunnel_down , },
# endif
{ "static" , static_up6 , static_down6 , },
{ "manual" , manual_up_down6 , manual_up_down6 , },
{ "loopback" , loopback_up6 , loopback_down6 , },
};
static const struct address_family_t addr_inet6 = {
"inet6",
ARRAY_SIZE(methods6),
methods6
};
#endif /* FEATURE_IFUPDOWN_IPV6 */
#if ENABLE_FEATURE_IFUPDOWN_IPV4
static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_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 FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_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 FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
{
int result;
# if ENABLE_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%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
result += execute("[[ip route add default via %gateway% dev %iface%[[ prio %metric%]]]]", ifd, exec);
return ((result == 3) ? 3 : 0);
# else
/* ifconfig said to set iface up before it processes hw %hwaddress%,
* which then of course fails. Thus we run two separate ifconfig */
result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
ifd, exec);
result += execute("ifconfig %iface% %address% netmask %netmask%"
"[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]] ",
ifd, exec);
result += execute("[[route add default gw %gateway%[[ metric %metric%]] %iface%]]", ifd, exec);
return ((result == 3) ? 3 : 0);
# endif
}
static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
{
int result;
# if ENABLE_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); */
/* Bringing the interface down deletes the routes in itself.
Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
result = 1;
result += execute("ifconfig %iface% down", ifd, exec);
# endif
return ((result == 2) ? 2 : 0);
}
# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
struct dhcp_client_t {
const char *name;
const char *startcmd;
const char *stopcmd;
};
static const struct dhcp_client_t ext_dhcp_clients[] = {
{ "dhcpcd",
"dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
"dhcpcd -k %iface%",
},
{ "dhclient",
"dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
"kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
},
{ "pump",
"pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
"pump -i %iface% -k",
},
{ "udhcpc",
"udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %client%]]"
"[[ -s %script%]][[ %udhcpc_opts%]]",
"kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
},
};
# endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
{
unsigned i;
# if ENABLE_FEATURE_IFUPDOWN_IP
/* ip doesn't up iface when it configures it (unlike ifconfig) */
if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
return 0;
# else
/* needed if we have hwaddress on dhcp iface */
if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
return 0;
# endif
for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
if (exists_execable(ext_dhcp_clients[i].name))
return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
}
bb_error_msg("no dhcp clients found");
return 0;
}
# elif ENABLE_UDHCPC
static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
{
# if ENABLE_FEATURE_IFUPDOWN_IP
/* ip doesn't up iface when it configures it (unlike ifconfig) */
if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
return 0;
# else
/* needed if we have hwaddress on dhcp iface */
if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
return 0;
# endif
return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
"-i %iface%[[ -H %hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
ifd, exec);
}
# else
static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
execfn *exec UNUSED_PARAM)
{
return 0; /* no dhcp support */
}
# endif
# if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
{
int result = 0;
unsigned i;
for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
if (exists_execable(ext_dhcp_clients[i].name)) {
result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
if (result)
break;
}
}
if (!result)
bb_error_msg("warning: no dhcp clients found and stopped");
/* Sleep a bit, otherwise static_down tries to bring down interface too soon,
and it may come back up because udhcpc is still shutting down */
usleep(100000);
result += static_down(ifd, exec);
return ((result == 3) ? 3 : 0);
}
# elif ENABLE_UDHCPC
static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
{
int result;
result = execute(
"test -f /var/run/udhcpc.%iface%.pid && "
"kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
ifd, exec);
/* Also bring the hardware interface down since
killing the dhcp client alone doesn't do it.
This enables consecutive ifup->ifdown->ifup */
/* Sleep a bit, otherwise static_down tries to bring down interface too soon,
and it may come back up because udhcpc is still shutting down */
usleep(100000);
result += static_down(ifd, exec);
return ((result == 3) ? 3 : 0);
}
# else
static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
execfn *exec UNUSED_PARAM)
{
return 0; /* no dhcp support */
}
# endif
static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
{
return 1;
}
static int FAST_FUNC 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 FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
{
return execute("pon[[ %provider%]]", ifd, exec);
}
static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
{
return execute("poff[[ %provider%]]", ifd, exec);
}
static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
{
return execute("start-stop-daemon --start -x wvdial "
"-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
}
static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
{
return execute("start-stop-daemon --stop -x wvdial "
"-p /var/run/wvdial.%iface% -s 2", ifd, exec);
}
static const struct method_t methods[] = {
{ "manual" , manual_up_down, manual_up_down, },
{ "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",
ARRAY_SIZE(methods),
methods
};
#endif /* FEATURE_IFUPDOWN_IPV4 */
/* Returns pointer to the next word, or NULL.
* In 1st case, advances *buf to the word after this one.
*/
static char *next_word(char **buf)
{
unsigned length;
char *word;
/* Skip over leading whitespace */
word = skip_whitespace(*buf);
/* Stop on EOL */
if (*word == '\0')
return NULL;
/* Find the length of this word (can't be 0) */
length = strcspn(word, " \t\n");
/* Unless we are already at NUL, store NUL and advance */
if (word[length] != '\0')
word[length++] = '\0';
*buf = skip_whitespace(word + length);
return word;
}
static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
{
int i;
if (!name)
return NULL;
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;
if (!name)
return NULL;
/* TODO: use index_in_str_array() */
for (i = 0; i < af->n_methods; i++) {
if (strcmp(af->method[i].name, name) == 0) {
return &af->method[i];
}
}
return NULL;
}
static struct interfaces_file_t *read_interfaces(const char *filename)
{
/* Let's try to be compatible.
*
* "man 5 interfaces" says:
* Lines starting with "#" are ignored. Note that end-of-line
* comments are NOT supported, comments must be on a line of their own.
* A line may be extended across multiple lines by making
* the last character a backslash.
*
* Seen elsewhere in example config file:
* A first non-blank "#" character makes the rest of the line
* be ignored. Blank lines are ignored. Lines may be indented freely.
* A "\" character at the very end of the line indicates the next line
* should be treated as a continuation of the current one.
*/
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
struct mapping_defn_t *currmap = NULL;
#endif
struct interface_defn_t *currif = NULL;
struct interfaces_file_t *defn;
FILE *f;
char *buf;
char *first_word;
char *rest_of_line;
enum { NONE, IFACE, MAPPING } currently_processing = NONE;
defn = xzalloc(sizeof(*defn));
f = xfopen_for_read(filename);
while ((buf = xmalloc_fgetline(f)) != NULL) {
#if ENABLE_DESKTOP
/* Trailing "\" concatenates lines */
char *p;
while ((p = last_char_is(buf, '\\')) != NULL) {
*p = '\0';
rest_of_line = xmalloc_fgetline(f);
if (!rest_of_line)
break;
p = xasprintf("%s%s", buf, rest_of_line);
free(buf);
free(rest_of_line);
buf = p;
}
#endif
rest_of_line = buf;
first_word = next_word(&rest_of_line);
if (!first_word || *first_word == '#') {
free(buf);
continue; /* blank/comment line */
}
if (strcmp(first_word, "mapping") == 0) {
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
currmap = xzalloc(sizeof(*currmap));
while ((first_word = next_word(&rest_of_line)) != NULL) {
currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
currmap->match[currmap->n_matches++] = xstrdup(first_word);
}
/*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(first_word, "iface") == 0) {
static const struct address_family_t *const addr_fams[] = {
#if ENABLE_FEATURE_IFUPDOWN_IPV4
&addr_inet,
#endif
#if ENABLE_FEATURE_IFUPDOWN_IPV6
&addr_inet6,
#endif
NULL
};
char *iface_name;
char *address_family_name;
char *method_name;
llist_t *iface_list;
currif = xzalloc(sizeof(*currif));
iface_name = next_word(&rest_of_line);
address_family_name = next_word(&rest_of_line);
method_name = next_word(&rest_of_line);
if (method_name == NULL)
bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
/* ship any trailing whitespace */
rest_of_line = skip_whitespace(rest_of_line);
if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
bb_error_msg_and_die("too many parameters \"%s\"", buf);
currif->iface = xstrdup(iface_name);
currif->address_family = get_address_family(addr_fams, address_family_name);
if (!currif->address_family)
bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
currif->method = get_method(currif->address_family, method_name);
if (!currif->method)
bb_error_msg_and_die("unknown method \"%s\"", method_name);
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_and_die("duplicate interface \"%s\"", tmp->iface);
}
}
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(first_word, "auto") == 0) {
while ((first_word = next_word(&rest_of_line)) != NULL) {
/* Check the interface isnt already listed */
if (llist_find_str(defn->autointerfaces, first_word)) {
bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
}
/* Add the interface to the list */
llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
debug_noise("\nauto %s\n", first_word);
}
currently_processing = NONE;
} else {
switch (currently_processing) {
case IFACE:
if (rest_of_line[0] == '\0')
bb_error_msg_and_die("option with empty value \"%s\"", buf);
/* If not one of "up", "down",... words... */
if (index_in_strings(keywords_up_down, first_word) < 0) {
int i;
for (i = 0; i < currif->n_options; i++) {
if (strcmp(currif->option[i].name, first_word) == 0)
bb_error_msg_and_die("duplicate option \"%s\"", buf);
}
}
debug_noise("\t%s=%s\n", first_word, rest_of_line);
currif->option = xrealloc_vector(currif->option, 4, currif->n_options);
currif->option[currif->n_options].name = xstrdup(first_word);
currif->option[currif->n_options].value = xstrdup(rest_of_line);
currif->n_options++;
break;
case MAPPING:
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
if (strcmp(first_word, "script") == 0) {
if (currmap->script != NULL)
bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
currmap->script = xstrdup(next_word(&rest_of_line));
} else if (strcmp(first_word, "map") == 0) {
currmap->mapping = xrealloc_vector(currmap->mapping, 2, currmap->n_mappings);
currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
currmap->n_mappings++;
} else {
bb_error_msg_and_die("misplaced option \"%s\"", buf);
}
#endif
break;
case NONE:
default:
bb_error_msg_and_die("misplaced option \"%s\"", buf);
}
}
free(buf);
} /* while (fgets) */
if (ferror(f) != 0) {
/* ferror does NOT set errno! */
bb_error_msg_and_die("%s: I/O error", filename);
}
fclose(f);
return defn;
}
static char *setlocalenv(const char *format, const char *name, const char *value)
{
char *result;
char *dst;
char *src;
char c;
result = xasprintf(format, name, value);
for (dst = src = result; (c = *src) != '=' && c; src++) {
if (c == '-')
c = '_';
if (c >= 'a' && c <= 'z')
c -= ('a' - 'A');
if (isalnum(c) || c == '_')
*dst++ = c;
}
overlapping_strcpy(dst, src);
return result;
}
static void set_environ(struct interface_defn_t *iface, const char *mode)
{
int i;
char **pp;
if (G.my_environ != NULL) {
for (pp = G.my_environ; *pp; pp++) {
free(*pp);
}
free(G.my_environ);
}
/* note: last element will stay NULL: */
G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 6));
pp = G.my_environ;
for (i = 0; i < iface->n_options; i++) {
if (index_in_strings(keywords_up_down, iface->option[i].name) >= 0) {
continue;
}
*pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
}
*pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
*pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
*pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
*pp++ = setlocalenv("%s=%s", "MODE", mode);
if (G.startup_PATH)
*pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
}
static int doit(char *str)
{
if (option_mask32 & (OPT_no_act|OPT_verbose)) {
puts(str);
}
if (!(option_mask32 & OPT_no_act)) {
pid_t child;
int status;
fflush_all();
child = vfork();
if (child < 0) /* failure */
return 0;
if (child == 0) { /* child */
execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
_exit(127);
}
safe_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);
/* heh, we don't bother free'ing it */
return doit(buf);
}
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;
if (!execute_all(iface, "post-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, "pre-down")) return 0;
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;
}
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
static int popen2(FILE **in, FILE **out, char *command, char *param)
{
char *argv[3] = { command, param, NULL };
struct fd_pair infd, outfd;
pid_t pid;
xpiped_pair(infd);
xpiped_pair(outfd);
fflush_all();
pid = xvfork();
if (pid == 0) {
/* Child */
/* NB: close _first_, then move fds! */
close(infd.wr);
close(outfd.rd);
xmove_fd(infd.rd, 0);
xmove_fd(outfd.wr, 1);
BB_EXECVP_or_die(argv);
}
/* parent */
close(infd.rd);
close(outfd.wr);
*in = xfdopen_for_write(infd.wr);
*out = xfdopen_for_read(outfd.rd);
return pid;
}
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. Never fails. */
pid = popen2(&in, &out, map->script, physical);
/* Write mappings to stdin of mapping script. */
for (i = 0; i < map->n_mappings; i++) {
fprintf(in, "%s\n", map->mapping[i]);
}
fclose(in);
safe_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 = xmalloc_fgetline(out);
if (new_logical) {
/* 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;
}
}
fclose(out);
return logical;
}
#endif /* FEATURE_IFUPDOWN_MAPPING */
static llist_t *find_iface_state(llist_t *state_list, const char *iface)
{
unsigned 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;
}
/* read the previous state from the state file */
static llist_t *read_iface_state(void)
{
llist_t *state_list = NULL;
FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
if (state_fp) {
char *start, *end_ptr;
while ((start = xmalloc_fgets(state_fp)) != NULL) {
/* We should only need to check for a single character */
end_ptr = start + strcspn(start, " \t\n");
*end_ptr = '\0';
llist_add_to(&state_list, start);
}
fclose(state_fp);
}
return state_list;
}
int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ifupdown_main(int argc UNUSED_PARAM, char **argv)
{
int (*cmds)(struct interface_defn_t *);
struct interfaces_file_t *defn;
llist_t *target_list = NULL;
const char *interfaces = "/etc/network/interfaces";
bool any_failures = 0;
INIT_G();
G.startup_PATH = getenv("PATH");
G.shell = xstrdup(get_shell_name());
cmds = iface_down;
if (applet_name[2] == 'u') {
/* ifup command */
cmds = iface_up;
}
getopt32(argv, OPTION_STR, &interfaces);
argv += optind;
if (argv[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);
/* Create a list of interfaces to work on */
if (DO_ALL) {
target_list = defn->autointerfaces;
} else {
llist_add_to_end(&target_list, argv[0]);
}
/* Update the interfaces */
while (target_list) {
llist_t *iface_list;
struct interface_defn_t *currif;
char *iface;
char *liface;
char *pch;
bool 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) {
llist_t *state_list = read_iface_state();
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);
goto next;
}
} else {
/* ifdown */
if (!iface_state) {
bb_error_msg("interface %s not configured", iface);
goto next;
}
}
llist_free(state_list, free);
}
#if ENABLE_FEATURE_IFUPDOWN_MAPPING
if ((cmds == iface_up) && !NO_MAPPINGS) {
struct mapping_defn_t *currmap;
for (currmap = defn->mappings; currmap; currmap = currmap->next) {
int i;
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) {
bb_putchar('\n');
}
if (!okay && !FORCE) {
bb_error_msg("ignoring unknown interface %s", liface);
any_failures = 1;
} else if (!NO_ACT) {
/* update the state file */
FILE *state_fp;
llist_t *state;
llist_t *state_list = read_iface_state();
llist_t *iface_state = find_iface_state(state_list, iface);
if (cmds == iface_up && !any_failures) {
char *newiface = xasprintf("%s=%s", iface, liface);
if (!iface_state) {
llist_add_to_end(&state_list, newiface);
} else {
free(iface_state->data);
iface_state->data = newiface;
}
} else {
/* Remove an interface from state_list */
llist_unlink(&state_list, iface_state);
free(llist_pop(&iface_state));
}
/* Actually write the new state */
state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
state = state_list;
while (state) {
if (state->data) {
fprintf(state_fp, "%s\n", state->data);
}
state = state->link;
}
fclose(state_fp);
llist_free(state_list, free);
}
next:
free(iface);
free(liface);
}
return any_failures;
}