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udhcp: merge options.h into common.h, script.c into dhcpc.c

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2010-03-22 14:29:13 +01:00
parent 8d1144565f
commit dde8bdcc5b
11 changed files with 490 additions and 536 deletions
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376
networking/udhcp/dhcpc.c
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@ -24,7 +24,6 @@
#include "common.h"
#include "dhcpd.h"
#include "dhcpc.h"
#include "options.h"
#include <asm/types.h>
#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(_NEWLIB_VERSION)
@ -36,34 +35,278 @@
#endif
#include <linux/filter.h>
static int sockfd = -1;
#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
#define LISTEN_RAW 2
static smallint listen_mode;
/* initial state: (re)start DHCP negotiation */
#define INIT_SELECTING 0
/* discover was sent, DHCPOFFER reply received */
#define REQUESTING 1
/* select/renew was sent, DHCPACK reply received */
#define BOUND 2
/* half of lease passed, want to renew it by sending unicast renew requests */
#define RENEWING 3
/* renew requests were not answered, lease is almost over, send broadcast renew */
#define REBINDING 4
/* manually requested renew (SIGUSR1) */
#define RENEW_REQUESTED 5
/* release, possibly manually requested (SIGUSR2) */
#define RELEASED 6
static smallint state;
/* struct client_config_t client_config is in bb_common_bufsiz1 */
/* Create a random xid */
/*** Script execution code ***/
/* get a rough idea of how long an option will be (rounding up...) */
static const uint8_t len_of_option_as_string[] = {
[OPTION_IP] = sizeof("255.255.255.255 "),
[OPTION_IP_PAIR] = sizeof("255.255.255.255 ") * 2,
[OPTION_STATIC_ROUTES]= sizeof("255.255.255.255/32 255.255.255.255 "),
[OPTION_STRING] = 1,
#if ENABLE_FEATURE_UDHCP_RFC3397
[OPTION_STR1035] = 1,
#endif
[OPTION_BOOLEAN] = sizeof("yes "),
[OPTION_U8] = sizeof("255 "),
[OPTION_U16] = sizeof("65535 "),
[OPTION_S16] = sizeof("-32768 "),
[OPTION_U32] = sizeof("4294967295 "),
[OPTION_S32] = sizeof("-2147483684 "),
};
/* note: ip is a pointer to an IP in network order, possibly misaliged */
static int sprint_nip(char *dest, const char *pre, const uint8_t *ip)
{
return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]);
}
/* really simple implementation, just count the bits */
static int mton(uint32_t mask)
{
int i = 0;
mask = ntohl(mask); /* 111110000-like bit pattern */
while (mask) {
i++;
mask <<= 1;
}
return i;
}
/* Create "opt_name=opt_value" string */
static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_option *type_p, const char *opt_name)
{
unsigned upper_length;
int len, type, optlen;
uint16_t val_u16;
int16_t val_s16;
uint32_t val_u32;
int32_t val_s32;
char *dest, *ret;
/* option points to OPT_DATA, need to go back and get OPT_LEN */
len = option[OPT_LEN - OPT_DATA];
type = type_p->flags & OPTION_TYPE_MASK;
optlen = dhcp_option_lengths[type];
upper_length = len_of_option_as_string[type] * (len / optlen);
dest = ret = xmalloc(upper_length + strlen(opt_name) + 2);
dest += sprintf(ret, "%s=", opt_name);
while (len >= optlen) {
switch (type) {
case OPTION_IP_PAIR:
dest += sprint_nip(dest, "", option);
*dest++ = '/';
option += 4;
optlen = 4;
case OPTION_IP:
dest += sprint_nip(dest, "", option);
// TODO: it can be a list only if (type_p->flags & OPTION_LIST).
// Should we bail out/warn if we see multi-ip option which is
// not allowed to be such? For example, DHCP_BROADCAST...
break;
case OPTION_BOOLEAN:
dest += sprintf(dest, *option ? "yes" : "no");
break;
case OPTION_U8:
dest += sprintf(dest, "%u", *option);
break;
case OPTION_U16:
move_from_unaligned16(val_u16, option);
dest += sprintf(dest, "%u", ntohs(val_u16));
break;
case OPTION_S16:
move_from_unaligned16(val_s16, option);
dest += sprintf(dest, "%d", ntohs(val_s16));
break;
case OPTION_U32:
move_from_unaligned32(val_u32, option);
dest += sprintf(dest, "%lu", (unsigned long) ntohl(val_u32));
break;
case OPTION_S32:
move_from_unaligned32(val_s32, option);
dest += sprintf(dest, "%ld", (long) ntohl(val_s32));
break;
case OPTION_STRING:
memcpy(dest, option, len);
dest[len] = '\0';
return ret; /* Short circuit this case */
case OPTION_STATIC_ROUTES: {
/* Option binary format:
* mask [one byte, 0..32]
* ip [big endian, 0..4 bytes depending on mask]
* router [big endian, 4 bytes]
* may be repeated
*
* We convert it to a string "IP/MASK ROUTER IP2/MASK2 ROUTER2"
*/
const char *pfx = "";
while (len >= 1 + 4) { /* mask + 0-byte ip + router */
uint32_t nip;
uint8_t *p;
unsigned mask;
int bytes;
mask = *option++;
if (mask > 32)
break;
len--;
nip = 0;
p = (void*) &nip;
bytes = (mask + 7) / 8; /* 0 -> 0, 1..8 -> 1, 9..16 -> 2 etc */
while (--bytes >= 0) {
*p++ = *option++;
len--;
}
if (len < 4)
break;
/* print ip/mask */
dest += sprint_nip(dest, pfx, (void*) &nip);
pfx = " ";
dest += sprintf(dest, "/%u ", mask);
/* print router */
dest += sprint_nip(dest, "", option);
option += 4;
len -= 4;
}
return ret;
}
#if ENABLE_FEATURE_UDHCP_RFC3397
case OPTION_STR1035:
/* unpack option into dest; use ret for prefix (i.e., "optname=") */
dest = dname_dec(option, len, ret);
if (dest) {
free(ret);
return dest;
}
/* error. return "optname=" string */
return ret;
#endif
}
option += optlen;
len -= optlen;
if (len <= 0)
break;
*dest++ = ' ';
*dest = '\0';
}
return ret;
}
/* put all the parameters into the environment */
static char **fill_envp(struct dhcp_packet *packet)
{
int num_options = 0;
int i;
char **envp, **curr;
const char *opt_name;
uint8_t *temp;
uint8_t over = 0;
if (packet) {
for (i = 0; dhcp_options[i].code; i++) {
if (udhcp_get_option(packet, dhcp_options[i].code)) {
num_options++;
if (dhcp_options[i].code == DHCP_SUBNET)
num_options++; /* for mton */
}
}
if (packet->siaddr_nip)
num_options++;
temp = udhcp_get_option(packet, DHCP_OPTION_OVERLOAD);
if (temp)
over = *temp;
if (!(over & FILE_FIELD) && packet->file[0])
num_options++;
if (!(over & SNAME_FIELD) && packet->sname[0])
num_options++;
}
curr = envp = xzalloc(sizeof(char *) * (num_options + 3));
*curr = xasprintf("interface=%s", client_config.interface);
putenv(*curr++);
if (packet == NULL)
return envp;
*curr = xmalloc(sizeof("ip=255.255.255.255"));
sprint_nip(*curr, "ip=", (uint8_t *) &packet->yiaddr);
putenv(*curr++);
opt_name = dhcp_option_strings;
i = 0;
while (*opt_name) {
temp = udhcp_get_option(packet, dhcp_options[i].code);
if (!temp)
goto next;
*curr = xmalloc_optname_optval(temp, &dhcp_options[i], opt_name);
putenv(*curr++);
/* Fill in a subnet bits option for things like /24 */
if (dhcp_options[i].code == DHCP_SUBNET) {
uint32_t subnet;
move_from_unaligned32(subnet, temp);
*curr = xasprintf("mask=%d", mton(subnet));
putenv(*curr++);
}
next:
opt_name += strlen(opt_name) + 1;
i++;
}
if (packet->siaddr_nip) {
*curr = xmalloc(sizeof("siaddr=255.255.255.255"));
sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
putenv(*curr++);
}
if (!(over & FILE_FIELD) && packet->file[0]) {
/* watch out for invalid packets */
*curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file);
putenv(*curr++);
}
if (!(over & SNAME_FIELD) && packet->sname[0]) {
/* watch out for invalid packets */
*curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
putenv(*curr++);
}
return envp;
}
/* Call a script with a par file and env vars */
static void udhcp_run_script(struct dhcp_packet *packet, const char *name)
{
char **envp, **curr;
char *argv[3];
if (client_config.script == NULL)
return;
envp = fill_envp(packet);
/* call script */
log1("Executing %s %s", client_config.script, name);
argv[0] = (char*) client_config.script;
argv[1] = (char*) name;
argv[2] = NULL;
spawn_and_wait(argv);
for (curr = envp; *curr; curr++) {
log2(" %s", *curr);
bb_unsetenv(*curr);
free(*curr);
}
free(envp);
}
/*** Sending/receiving packets ***/
static ALWAYS_INLINE uint32_t random_xid(void)
{
return rand();
@ -75,16 +318,16 @@ static void init_packet(struct dhcp_packet *packet, char type)
udhcp_init_header(packet, type);
memcpy(packet->chaddr, client_config.client_mac, 6);
if (client_config.clientid)
add_option_string(packet->options, client_config.clientid);
udhcp_add_option_string(packet->options, client_config.clientid);
if (client_config.hostname)
add_option_string(packet->options, client_config.hostname);
udhcp_add_option_string(packet->options, client_config.hostname);
if (client_config.fqdn)
add_option_string(packet->options, client_config.fqdn);
udhcp_add_option_string(packet->options, client_config.fqdn);
if (type != DHCPDECLINE
&& type != DHCPRELEASE
&& client_config.vendorclass
) {
add_option_string(packet->options, client_config.vendorclass);
udhcp_add_option_string(packet->options, client_config.vendorclass);
}
}
@ -94,7 +337,7 @@ static void init_packet(struct dhcp_packet *packet, char type)
static void add_param_req_option(struct dhcp_packet *packet)
{
uint8_t c;
int end = end_option(packet->options);
int end = udhcp_end_option(packet->options);
int i, len = 0;
for (i = 0; (c = dhcp_options[i].code) != 0; i++) {
@ -148,10 +391,10 @@ static int send_discover(uint32_t xid, uint32_t requested)
init_packet(&packet, DHCPDISCOVER);
packet.xid = xid;
if (requested)
add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
udhcp_add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
/* Explicitly saying that we want RFC-compliant packets helps
* some buggy DHCP servers to NOT send bigger packets */
add_simple_option(packet.options, DHCP_MAX_SIZE, htons(576));
udhcp_add_simple_option(packet.options, DHCP_MAX_SIZE, htons(576));
add_param_req_option(&packet);
bb_info_msg("Sending discover...");
@ -169,8 +412,8 @@ static int send_select(uint32_t xid, uint32_t server, uint32_t requested)
init_packet(&packet, DHCPREQUEST);
packet.xid = xid;
add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
add_simple_option(packet.options, DHCP_SERVER_ID, server);
udhcp_add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
udhcp_add_simple_option(packet.options, DHCP_SERVER_ID, server);
add_param_req_option(&packet);
addr.s_addr = requested;
@ -204,8 +447,8 @@ static int send_decline(uint32_t xid, uint32_t server, uint32_t requested)
init_packet(&packet, DHCPDECLINE);
packet.xid = xid;
add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
add_simple_option(packet.options, DHCP_SERVER_ID, server);
udhcp_add_simple_option(packet.options, DHCP_REQUESTED_IP, requested);
udhcp_add_simple_option(packet.options, DHCP_SERVER_ID, server);
bb_info_msg("Sending decline...");
return raw_bcast_from_client_config_ifindex(&packet);
@ -221,7 +464,7 @@ static int send_release(uint32_t server, uint32_t ciaddr)
packet.xid = random_xid();
packet.ciaddr = ciaddr;
add_simple_option(packet.options, DHCP_SERVER_ID, server);
udhcp_add_simple_option(packet.options, DHCP_SERVER_ID, server);
bb_info_msg("Sending release...");
return udhcp_send_kernel_packet(&packet, ciaddr, CLIENT_PORT, server, SERVER_PORT);
@ -297,6 +540,32 @@ static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd)
return bytes - (sizeof(packet.ip) + sizeof(packet.udp));
}
/*** Main ***/
static int sockfd = -1;
#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
#define LISTEN_RAW 2
static smallint listen_mode;
/* initial state: (re)start DHCP negotiation */
#define INIT_SELECTING 0
/* discover was sent, DHCPOFFER reply received */
#define REQUESTING 1
/* select/renew was sent, DHCPACK reply received */
#define BOUND 2
/* half of lease passed, want to renew it by sending unicast renew requests */
#define RENEWING 3
/* renew requests were not answered, lease is almost over, send broadcast renew */
#define REBINDING 4
/* manually requested renew (SIGUSR1) */
#define RENEW_REQUESTED 5
/* release, possibly manually requested (SIGUSR2) */
#define RELEASED 6
static smallint state;
static int udhcp_raw_socket(int ifindex)
{
int fd;
@ -368,7 +637,6 @@ static int udhcp_raw_socket(int ifindex)
return fd;
}
/* just a little helper */
static void change_listen_mode(int new_mode)
{
log1("Entering listen mode: %s",
@ -389,7 +657,6 @@ static void change_listen_mode(int new_mode)
/* else LISTEN_NONE: sockfd stays closed */
}
/* perform a renew */
static void perform_renew(void)
{
bb_info_msg("Performing a DHCP renew");
@ -412,7 +679,6 @@ static void perform_renew(void)
}
}
/* perform a release */
static void perform_release(uint32_t requested_ip, uint32_t server_addr)
{
char buffer[sizeof("255.255.255.255")];
@ -434,16 +700,6 @@ static void perform_release(uint32_t requested_ip, uint32_t server_addr)
state = RELEASED;
}
#if BB_MMU
static void client_background(void)
{
bb_daemonize(0);
logmode &= ~LOGMODE_STDIO;
/* rewrite pidfile, as our pid is different now */
write_pidfile(client_config.pidfile);
}
#endif
static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
{
uint8_t *storage;
@ -455,6 +711,16 @@ static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
return storage;
}
#if BB_MMU
static void client_background(void)
{
bb_daemonize(0);
logmode &= ~LOGMODE_STDIO;
/* rewrite pidfile, as our pid is different now */
write_pidfile(client_config.pidfile);
}
#endif
int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int udhcpc_main(int argc UNUSED_PARAM, char **argv)
{
@ -541,7 +807,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;)
IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
client_config.interface = "eth0";
client_config.script = DEFAULT_SCRIPT;
client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
str_V = "udhcp "BB_VER;
/* Parse command line */
@ -861,7 +1127,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
continue;
}
message = get_option(&packet, DHCP_MESSAGE_TYPE);
message = udhcp_get_option(&packet, DHCP_MESSAGE_TYPE);
if (message == NULL) {
bb_error_msg("no message type option, ignoring packet");
continue;
@ -872,7 +1138,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* Must be a DHCPOFFER to one of our xid's */
if (*message == DHCPOFFER) {
/* TODO: why we don't just fetch server's IP from IP header? */
temp = get_option(&packet, DHCP_SERVER_ID);
temp = udhcp_get_option(&packet, DHCP_SERVER_ID);
if (!temp) {
bb_error_msg("no server ID in message");
continue;
@ -895,7 +1161,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
case RENEW_REQUESTED:
case REBINDING:
if (*message == DHCPACK) {
temp = get_option(&packet, DHCP_LEASE_TIME);
temp = udhcp_get_option(&packet, DHCP_LEASE_TIME);
if (!temp) {
bb_error_msg("no lease time with ACK, using 1 hour lease");
lease_seconds = 60 * 60;