/* script.c
*
- * Functions to call the DHCP client notification scripts
+ * Functions to call the DHCP client notification scripts
*
* Russ Dill <Russ.Dill@asu.edu> July 2001
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include <string.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/wait.h>
-#include <errno.h>
+#include "common.h"
#include "options.h"
#include "dhcpd.h"
#include "dhcpc.h"
-#include "packet.h"
-#include "options.h"
-#include "debug.h"
-
-#include "config.h"
/* get a rough idea of how long an option will be (rounding up...) */
-static int max_option_length[] = {
+static const int max_option_length[] = {
[OPTION_IP] = sizeof("255.255.255.255 "),
[OPTION_IP_PAIR] = sizeof("255.255.255.255 ") * 2,
[OPTION_STRING] = 1,
};
-static int upper_length(int length, struct dhcp_option *option)
+static inline int upper_length(int length, int opt_index)
{
- return max_option_length[option->flags & TYPE_MASK] *
- (length / option_lengths[option->flags & TYPE_MASK]);
+ return max_option_length[opt_index] *
+ (length / option_lengths[opt_index]);
}
-static int sprintip(char *dest, char *pre, unsigned char *ip) {
- return sprintf(dest, "%s%d.%d.%d.%d ", pre, ip[0], ip[1], ip[2], ip[3]);
-}
-
-#ifdef CONFIG_FEATURE_UDHCPC_IP
-/* convert a netmask (255.255.255.0) into the length (24) */
-static int inet_ntom (const char *src, short *dst)
+static int sprintip(char *dest, char *pre, uint8_t *ip)
{
- in_addr_t mask, num;
-
- mask = ntohl(*(unsigned int *)src);
-
- for (num = mask; num & 1; num >>= 1);
-
- if (num != 0 && mask != 0)
- {
- for (num = ~mask; num & 1; num >>= 1);
- if (num)
- return 0;
- }
-
- for (num = 0; mask; mask <<= 1)
- num++;
+ return sprintf(dest, "%s%d.%d.%d.%d", pre, ip[0], ip[1], ip[2], ip[3]);
+}
- *dst = num;
- return 1;
+/* really simple implementation, just count the bits */
+static int mton(struct in_addr *mask)
+{
+ int i;
+ unsigned long bits = ntohl(mask->s_addr);
+ /* too bad one can't check the carry bit, etc in c bit
+ * shifting */
+ for (i = 0; i < 32 && !((bits >> i) & 1); i++);
+ return 32 - i;
}
-static int sprintprefix(char *dest, char *pre, unsigned char *ip) {
- short sdest = 0;
- inet_ntom(ip, &sdest);
- return sprintf(dest, "%s%hd ", pre, sdest);
-}
-#endif
/* Fill dest with the text of option 'option'. */
-static void fill_options(char *dest, unsigned char *option, struct dhcp_option *type_p)
+static void fill_options(char *dest, uint8_t *option, struct dhcp_option *type_p)
{
int type, optlen;
- u_int16_t val_u16;
+ uint16_t val_u16;
int16_t val_s16;
- u_int32_t val_u32;
+ uint32_t val_u32;
int32_t val_s32;
int len = option[OPT_LEN - 2];
*(dest++) = '/';
option += 4;
optlen = 4;
-#ifndef CONFIG_FEATURE_UDHCPC_IP
case OPTION_IP: /* Works regardless of host byte order. */
-#endif
dest += sprintip(dest, "", option);
- break;
-#ifdef CONFIG_FEATURE_UDHCPC_IP
- case OPTION_IP: /* Works regardless of host byte order. */
- if (type_p->flags & OPTION_PREFIX) {
- dest += sprintprefix(dest, "", option);
- } else {
- dest += sprintip(dest, "", option);
- }
- break;
-#endif
+ break;
case OPTION_BOOLEAN:
- dest += sprintf(dest, *option ? "yes " : "no ");
+ dest += sprintf(dest, *option ? "yes" : "no");
break;
case OPTION_U8:
- dest += sprintf(dest, "%u ", *option);
+ dest += sprintf(dest, "%u", *option);
break;
case OPTION_U16:
memcpy(&val_u16, option, 2);
- dest += sprintf(dest, "%u ", ntohs(val_u16));
+ dest += sprintf(dest, "%u", ntohs(val_u16));
break;
case OPTION_S16:
memcpy(&val_s16, option, 2);
- dest += sprintf(dest, "%d ", ntohs(val_s16));
+ dest += sprintf(dest, "%d", ntohs(val_s16));
break;
case OPTION_U32:
memcpy(&val_u32, option, 4);
- dest += sprintf(dest, "%lu ", (unsigned long) ntohl(val_u32));
+ dest += sprintf(dest, "%lu", (unsigned long) ntohl(val_u32));
break;
case OPTION_S32:
memcpy(&val_s32, option, 4);
- dest += sprintf(dest, "%ld ", (long) ntohl(val_s32));
+ dest += sprintf(dest, "%ld", (long) ntohl(val_s32));
break;
case OPTION_STRING:
memcpy(dest, option, len);
option += optlen;
len -= optlen;
if (len <= 0) break;
+ dest += sprintf(dest, " ");
}
}
-static char *find_env(const char *prefix, char *defaultstr)
-{
- extern char **environ;
- char **ptr;
- const int len = strlen(prefix);
-
- for (ptr = environ; *ptr != NULL; ptr++) {
- if (strncmp(prefix, *ptr, len) == 0)
- return *ptr;
- }
- return defaultstr;
-}
-
-
-/* put all the paramaters into an environment */
+/* put all the parameters into an environment */
static char **fill_envp(struct dhcpMessage *packet)
{
int num_options = 0;
int i, j;
char **envp;
- unsigned char *temp;
+ uint8_t *temp;
+ struct in_addr subnet;
char over = 0;
if (packet == NULL)
num_options = 0;
else {
- for (i = 0; options[i].code; i++)
- if (get_option(packet, options[i].code))
+ for (i = 0; dhcp_options[i].code; i++)
+ if (get_option(packet, dhcp_options[i].code)) {
num_options++;
+ if (dhcp_options[i].code == DHCP_SUBNET)
+ num_options++; /* for mton */
+ }
if (packet->siaddr) num_options++;
if ((temp = get_option(packet, DHCP_OPTION_OVER)))
over = *temp;
if (!(over & FILE_FIELD) && packet->file[0]) num_options++;
- if (!(over & SNAME_FIELD) && packet->sname[0]) num_options++;
+ if (!(over & SNAME_FIELD) && packet->sname[0]) num_options++;
}
-
- envp = xmalloc((num_options + 5) * sizeof(char *));
- envp[0] = xmalloc(sizeof("interface=") + strlen(client_config.interface));
- sprintf(envp[0], "interface=%s", client_config.interface);
- envp[1] = find_env("PATH", "PATH=/bin:/usr/bin:/sbin:/usr/sbin");
- envp[2] = find_env("HOME", "HOME=/");
- if (packet == NULL) {
- envp[3] = NULL;
- return envp;
- }
+ envp = xzalloc(sizeof(char *) * (num_options + 5));
+ j = 0;
+ envp[j++] = bb_xasprintf("interface=%s", client_config.interface);
+ envp[j++] = bb_xasprintf("PATH=%s",
+ getenv("PATH") ? : "/bin:/usr/bin:/sbin:/usr/sbin");
+ envp[j++] = bb_xasprintf("HOME=%s", getenv("HOME") ? : "/");
+
+ if (packet == NULL) return envp;
- envp[3] = xmalloc(sizeof("ip=255.255.255.255"));
- sprintip(envp[3], "ip=", (unsigned char *) &packet->yiaddr);
- for (i = 0, j = 4; options[i].code; i++) {
- if ((temp = get_option(packet, options[i].code))) {
- envp[j] = xmalloc(upper_length(temp[OPT_LEN - 2], &options[i]) + strlen(options[i].name) + 2);
- fill_options(envp[j], temp, &options[i]);
- j++;
+ envp[j] = xmalloc(sizeof("ip=255.255.255.255"));
+ sprintip(envp[j++], "ip=", (uint8_t *) &packet->yiaddr);
+
+
+ for (i = 0; dhcp_options[i].code; i++) {
+ if (!(temp = get_option(packet, dhcp_options[i].code)))
+ continue;
+ envp[j] = xmalloc(upper_length(temp[OPT_LEN - 2],
+ dhcp_options[i].flags & TYPE_MASK) + strlen(dhcp_options[i].name) + 2);
+ fill_options(envp[j++], temp, &dhcp_options[i]);
+
+ /* Fill in a subnet bits option for things like /24 */
+ if (dhcp_options[i].code == DHCP_SUBNET) {
+ memcpy(&subnet, temp, 4);
+ envp[j++] = bb_xasprintf("mask=%d", mton(&subnet));
}
}
if (packet->siaddr) {
envp[j] = xmalloc(sizeof("siaddr=255.255.255.255"));
- sprintip(envp[j++], "siaddr=", (unsigned char *) &packet->siaddr);
+ sprintip(envp[j++], "siaddr=", (uint8_t *) &packet->siaddr);
}
if (!(over & FILE_FIELD) && packet->file[0]) {
/* watch out for invalid packets */
packet->file[sizeof(packet->file) - 1] = '\0';
- envp[j] = xmalloc(sizeof("boot_file=") + strlen(packet->file));
- sprintf(envp[j++], "boot_file=%s", packet->file);
+ envp[j++] = bb_xasprintf("boot_file=%s", packet->file);
}
if (!(over & SNAME_FIELD) && packet->sname[0]) {
/* watch out for invalid packets */
packet->sname[sizeof(packet->sname) - 1] = '\0';
- envp[j] = xmalloc(sizeof("sname=") + strlen(packet->sname));
- sprintf(envp[j++], "sname=%s", packet->sname);
- }
- envp[j] = NULL;
+ envp[j++] = bb_xasprintf("sname=%s", packet->sname);
+ }
return envp;
}
/* Call a script with a par file and env vars */
-void run_script(struct dhcpMessage *packet, const char *name)
+void udhcp_run_script(struct dhcpMessage *packet, const char *name)
{
int pid;
- char **envp;
+ char **envp, **curr;
if (client_config.script == NULL)
return;
+ DEBUG(LOG_INFO, "vforking and execle'ing %s", client_config.script);
+
+ envp = fill_envp(packet);
/* call script */
- pid = fork();
+ pid = vfork();
if (pid) {
waitpid(pid, NULL, 0);
+ for (curr = envp; *curr; curr++) free(*curr);
+ free(envp);
return;
} else if (pid == 0) {
- envp = fill_envp(packet);
-
/* close fd's? */
-
+
/* exec script */
- DEBUG(LOG_INFO, "execle'ing %s", client_config.script);
execle(client_config.script, client_config.script,
name, NULL, envp);
- LOG(LOG_ERR, "script %s failed: %s",
- client_config.script, strerror(errno));
+ LOG(LOG_ERR, "script %s failed: %m", client_config.script);
exit(1);
- }
+ }
}
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