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authorDenys Vlasenko2010-03-22 14:29:13 +0100
committerDenys Vlasenko2010-03-22 14:29:13 +0100
commitdde8bdcc5bd6f25157ca5364b2991c837f1ef364 (patch)
treed1947e02af92db440b8f8b9e16659ff8568d7e62 /networking/udhcp/dhcpc.c
parent8d1144565fd01576b72eac65ce4686405f98829e (diff)
downloadbusybox-dde8bdcc5bd6f25157ca5364b2991c837f1ef364.zip
busybox-dde8bdcc5bd6f25157ca5364b2991c837f1ef364.tar.gz
udhcp: merge options.h into common.h, script.c into dhcpc.c
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'networking/udhcp/dhcpc.c')
-rw-r--r--networking/udhcp/dhcpc.c370
1 files changed, 318 insertions, 52 deletions
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index e79feb7..7587509 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -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>
+/* struct client_config_t client_config is in bb_common_bufsiz1 */
-static int sockfd = -1;
-#define LISTEN_NONE 0
-#define LISTEN_KERNEL 1
-#define LISTEN_RAW 2
-static smallint listen_mode;
+/*** Script execution code ***/
-/* 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;
+/* 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]);
+}
-/* struct client_config_t client_config is in bb_common_bufsiz1 */
+/* 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);
+}
-/* Create a random xid */
+/*** 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;