1 /* vi: set sw=4 ts=4: */
4 * Functions to call the DHCP client notification scripts
6 * Russ Dill <Russ.Dill@asu.edu> July 2001
8 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
16 /* get a rough idea of how long an option will be (rounding up...) */
17 static const uint8_t len_of_option_as_string[] = {
18 [OPTION_IP] = sizeof("255.255.255.255 "),
19 [OPTION_IP_PAIR] = sizeof("255.255.255.255 ") * 2,
20 [OPTION_STATIC_ROUTES]= sizeof("255.255.255.255/32 255.255.255.255 "),
22 #if ENABLE_FEATURE_UDHCP_RFC3397
25 [OPTION_BOOLEAN] = sizeof("yes "),
26 [OPTION_U8] = sizeof("255 "),
27 [OPTION_U16] = sizeof("65535 "),
28 [OPTION_S16] = sizeof("-32768 "),
29 [OPTION_U32] = sizeof("4294967295 "),
30 [OPTION_S32] = sizeof("-2147483684 "),
34 /* note: ip is a pointer to an IP in network order, possibly misaliged */
35 static int sprint_nip(char *dest, const char *pre, const uint8_t *ip)
37 return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]);
41 /* really simple implementation, just count the bits */
42 static int mton(uint32_t mask)
45 mask = ntohl(mask); /* 111110000-like bit pattern */
54 /* Create "opt_name=opt_value" string */
55 static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_option *type_p, const char *opt_name)
57 unsigned upper_length;
58 int len, type, optlen;
65 /* option points to OPT_DATA, need to go back and get OPT_LEN */
66 len = option[OPT_LEN - OPT_DATA];
67 type = type_p->flags & TYPE_MASK;
68 optlen = dhcp_option_lengths[type];
69 upper_length = len_of_option_as_string[type] * (len / optlen);
71 dest = ret = xmalloc(upper_length + strlen(opt_name) + 2);
72 dest += sprintf(ret, "%s=", opt_name);
74 while (len >= optlen) {
77 dest += sprint_nip(dest, "", option);
81 case OPTION_IP: /* Works regardless of host byte order. */
82 dest += sprint_nip(dest, "", option);
85 dest += sprintf(dest, *option ? "yes" : "no");
88 dest += sprintf(dest, "%u", *option);
91 move_from_unaligned16(val_u16, option);
92 dest += sprintf(dest, "%u", ntohs(val_u16));
95 move_from_unaligned16(val_s16, option);
96 dest += sprintf(dest, "%d", ntohs(val_s16));
99 move_from_unaligned32(val_u32, option);
100 dest += sprintf(dest, "%lu", (unsigned long) ntohl(val_u32));
103 move_from_unaligned32(val_s32, option);
104 dest += sprintf(dest, "%ld", (long) ntohl(val_s32));
107 memcpy(dest, option, len);
109 return ret; /* Short circuit this case */
110 case OPTION_STATIC_ROUTES: {
111 /* Option binary format:
112 * mask [one byte, 0..32]
113 * ip [big endian, 0..4 bytes depending on mask]
114 * router [big endian, 4 bytes]
117 * We convert it to a string "IP/MASK ROUTER IP2/MASK2 ROUTER2"
119 const char *pfx = "";
121 while (len >= 1 + 4) { /* mask + 0-byte ip + router */
134 bytes = (mask + 7) / 8; /* 0 -> 0, 1..8 -> 1, 9..16 -> 2 etc */
135 while (--bytes >= 0) {
143 dest += sprint_nip(dest, pfx, (void*) &nip);
145 dest += sprintf(dest, "/%u ", mask);
147 dest += sprint_nip(dest, "", option);
154 #if ENABLE_FEATURE_UDHCP_RFC3397
156 /* unpack option into dest; use ret for prefix (i.e., "optname=") */
157 dest = dname_dec(option, len, ret);
162 /* error. return "optname=" string */
177 /* put all the parameters into an environment */
178 static char **fill_envp(struct dhcp_packet *packet)
183 const char *opt_name;
188 for (i = 0; dhcp_options[i].code; i++) {
189 if (get_option(packet, dhcp_options[i].code)) {
191 if (dhcp_options[i].code == DHCP_SUBNET)
192 num_options++; /* for mton */
195 if (packet->siaddr_nip)
197 temp = get_option(packet, DHCP_OPTION_OVERLOAD);
200 if (!(over & FILE_FIELD) && packet->file[0])
202 if (!(over & SNAME_FIELD) && packet->sname[0])
206 curr = envp = xzalloc(sizeof(char *) * (num_options + 3));
207 *curr = xasprintf("interface=%s", client_config.interface);
213 *curr = xmalloc(sizeof("ip=255.255.255.255"));
214 sprint_nip(*curr, "ip=", (uint8_t *) &packet->yiaddr);
217 opt_name = dhcp_option_strings;
220 temp = get_option(packet, dhcp_options[i].code);
223 *curr = xmalloc_optname_optval(temp, &dhcp_options[i], opt_name);
226 /* Fill in a subnet bits option for things like /24 */
227 if (dhcp_options[i].code == DHCP_SUBNET) {
229 move_from_unaligned32(subnet, temp);
230 *curr = xasprintf("mask=%d", mton(subnet));
234 opt_name += strlen(opt_name) + 1;
237 if (packet->siaddr_nip) {
238 *curr = xmalloc(sizeof("siaddr=255.255.255.255"));
239 sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
242 if (!(over & FILE_FIELD) && packet->file[0]) {
243 /* watch out for invalid packets */
244 packet->file[sizeof(packet->file) - 1] = '\0';
245 *curr = xasprintf("boot_file=%s", packet->file);
248 if (!(over & SNAME_FIELD) && packet->sname[0]) {
249 /* watch out for invalid packets */
250 packet->sname[sizeof(packet->sname) - 1] = '\0';
251 *curr = xasprintf("sname=%s", packet->sname);
258 /* Call a script with a par file and env vars */
259 void FAST_FUNC udhcp_run_script(struct dhcp_packet *packet, const char *name)
264 if (client_config.script == NULL)
267 envp = fill_envp(packet);
270 log1("Executing %s %s", client_config.script, name);
271 argv[0] = (char*) client_config.script;
272 argv[1] = (char*) name;
274 wait4pid(spawn(argv));
276 for (curr = envp; *curr; curr++) {