busybox/networking/ifupdown.c

1305 lines
32 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 the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include <sys/utsname.h>
#include <fnmatch.h>
#include <getopt.h>
#include "libbb.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 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);
int (*down)(struct interface_defn_t *ifd, execfn *e);
};
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 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;
};
#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_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)
static char **my_environ;
static const char *startup_PATH;
#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 -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) {
char *result;
static char label_buf[20];
safe_strncpy(label_buf, ifd->iface, sizeof(label_buf));
result = strchr(label_buf, ':');
if (result) {
*result = '\0';
}
return label_buf;
}
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) {
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
#if ENABLE_FEATURE_IFUPDOWN_IPV6
static int 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 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 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%]][[ address %hwaddress%]] %iface% up", ifd, exec);
/* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
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)
{
#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 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[] = {
#if ENABLE_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",
ARRAY_SIZE(methods6),
methods6
};
#endif /* FEATURE_IFUPDOWN_IPV6 */
#if ENABLE_FEATURE_IFUPDOWN_IPV4
static int 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 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 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%]][[ address %hwaddress%]] %iface% up", ifd, exec);
result += execute("[[ip route add default via %gateway% dev %iface%]]", 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% %iface%]]", ifd, exec);
return ((result == 3) ? 3 : 0);
#endif
}
static int 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);
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 %clientid%]][[ -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 -R -n -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
"kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
},
};
#endif /* ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
{
#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
int i;
#if ENABLE_FEATURE_IFUPDOWN_IP
/* ip doesn't up iface when it configures it (unlike ifconfig) */
if (!execute("ip link set %iface% 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_APP_UDHCPC
#if ENABLE_FEATURE_IFUPDOWN_IP
/* ip doesn't up iface when it configures it (unlike ifconfig) */
if (!execute("ip link set %iface% up", ifd, exec))
return 0;
#endif
return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
"-i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
ifd, exec);
#else
return 0; /* no dhcp support */
#endif
}
static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
{
#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
int i;
for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
if (exists_execable(ext_dhcp_clients[i].name))
return execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
}
bb_error_msg("no dhcp clients found, using static interface shutdown");
return static_down(ifd, exec);
#elif ENABLE_APP_UDHCPC
return execute("kill "
"`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
#else
return 0; /* no dhcp support */
#endif
}
static int manual_up_down(struct interface_defn_t *ifd, execfn *exec)
{
return 1;
}
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("start-stop-daemon --start -x wvdial "
"-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
}
static int 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 /* if ENABLE_FEATURE_IFUPDOWN_IPV4 */
static char *next_word(char **buf)
{
unsigned short length;
char *word;
if (!buf || !*buf || !**buf) {
return NULL;
}
/* Skip over leading whitespace */
word = skip_whitespace(*buf);
/* 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;
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;
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)
{
if (string == NULL)
return NULL;
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)
{
#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 *firstword;
char *buf;
enum { NONE, IFACE, MAPPING } currently_processing = NONE;
defn = xzalloc(sizeof(struct interfaces_file_t));
f = xfopen(filename, "r");
while ((buf = xmalloc_getline(f)) != NULL) {
char *buf_ptr = buf;
firstword = next_word(&buf_ptr);
if (firstword == NULL) {
free(buf);
continue; /* blank line */
}
if (strcmp(firstword, "mapping") == 0) {
#if ENABLE_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[] = {
#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(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 */
buf_ptr = skip_whitespace(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:
#if ENABLE_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) {
/* 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 *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 (my_environ != NULL) {
for (ppch = my_environ; *ppch; ppch++) {
free(*ppch);
*ppch = NULL;
}
free(my_environ);
}
my_environ = xzalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
environend = my_environ;
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_mask32 & (OPT_no_act|OPT_verbose)) {
puts(str);
}
if (!(option_mask32 & OPT_no_act)) {
pid_t child;
int status;
fflush(NULL);
child = fork();
switch (child) {
case -1: /* failure */
return 0;
case 0: /* child */
execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, NULL, my_environ);
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);
/* 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;
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;
}
#if ENABLE_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]);
BB_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 = 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 /* 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;
}
/* read the previous state from the state file */
static llist_t *read_iface_state(void)
{
llist_t *state_list = NULL;
FILE *state_fp = fopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "r");
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);
int ifupdown_main(int argc, char **argv)
{
int (*cmds)(struct interface_defn_t *) = NULL;
struct interfaces_file_t *defn;
llist_t *target_list = NULL;
const char *interfaces = "/etc/network/interfaces";
bool any_failures = 0;
cmds = iface_down;
if (applet_name[2] == 'u') {
/* ifup command */
cmds = iface_up;
}
getopt32(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) {
return EXIT_FAILURE;
}
startup_PATH = getenv("PATH");
if (!startup_PATH) startup_PATH = "";
/* Create a list of interfaces to work on */
if (DO_ALL) {
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;
bool okay = 0;
unsigned 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);
continue;
}
} else {
/* ifdown */
if (!iface_state) {
bb_error_msg("interface %s not configured", iface);
continue;
}
}
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) {
char * const 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 state_list */
llist_unlink(&state_list, iface_state);
free(llist_pop(&iface_state));
}
/* Actually write the new state */
state_fp = xfopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "w");
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);
}
}
return any_failures;
}