1 /* vi: set sw=4 ts=4: */
3 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
5 * Licensed under GPLv2, see file LICENSE in this source tree.
9 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
10 unsigned dhcp_verbose;
13 const uint8_t MAC_BCAST_ADDR[6] ALIGN2 = {
14 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
17 #if ENABLE_UDHCPC || ENABLE_UDHCPD
18 /* Supported options are easily added here.
19 * See RFC2132 for more options.
20 * OPTION_REQ: these options are requested by udhcpc (unless -o).
22 const struct dhcp_optflag dhcp_optflags[] = {
24 { OPTION_IP | OPTION_REQ, 0x01 }, /* DHCP_SUBNET */
25 { OPTION_S32 , 0x02 }, /* DHCP_TIME_OFFSET */
26 { OPTION_IP | OPTION_LIST | OPTION_REQ, 0x03 }, /* DHCP_ROUTER */
27 // { OPTION_IP | OPTION_LIST , 0x04 }, /* DHCP_TIME_SERVER */
28 // { OPTION_IP | OPTION_LIST , 0x05 }, /* DHCP_NAME_SERVER */
29 { OPTION_IP | OPTION_LIST | OPTION_REQ, 0x06 }, /* DHCP_DNS_SERVER */
30 // { OPTION_IP | OPTION_LIST , 0x07 }, /* DHCP_LOG_SERVER */
31 // { OPTION_IP | OPTION_LIST , 0x08 }, /* DHCP_COOKIE_SERVER */
32 { OPTION_IP | OPTION_LIST , 0x09 }, /* DHCP_LPR_SERVER */
33 { OPTION_STRING_HOST | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME */
34 { OPTION_U16 , 0x0d }, /* DHCP_BOOT_SIZE */
35 { OPTION_STRING_HOST | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME */
36 { OPTION_IP , 0x10 }, /* DHCP_SWAP_SERVER */
37 { OPTION_STRING , 0x11 }, /* DHCP_ROOT_PATH */
38 { OPTION_U8 , 0x17 }, /* DHCP_IP_TTL */
39 { OPTION_U16 , 0x1a }, /* DHCP_MTU */
40 //TODO: why do we request DHCP_BROADCAST? Can't we assume that
41 //in the unlikely case it is different from typical N.N.255.255,
42 //server would let us know anyway?
43 { OPTION_IP | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST */
44 { OPTION_IP_PAIR | OPTION_LIST , 0x21 }, /* DHCP_ROUTES */
45 { OPTION_STRING_HOST , 0x28 }, /* DHCP_NIS_DOMAIN */
46 { OPTION_IP | OPTION_LIST , 0x29 }, /* DHCP_NIS_SERVER */
47 { OPTION_IP | OPTION_LIST | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER */
48 { OPTION_IP | OPTION_LIST , 0x2c }, /* DHCP_WINS_SERVER */
49 { OPTION_U32 , 0x33 }, /* DHCP_LEASE_TIME */
50 { OPTION_IP , 0x36 }, /* DHCP_SERVER_ID */
51 { OPTION_STRING , 0x38 }, /* DHCP_ERR_MESSAGE */
52 //TODO: must be combined with 'sname' and 'file' handling:
53 { OPTION_STRING_HOST , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
54 { OPTION_STRING , 0x43 }, /* DHCP_BOOT_FILE */
55 //TODO: not a string, but a set of LASCII strings:
56 // { OPTION_STRING , 0x4D }, /* DHCP_USER_CLASS */
57 { OPTION_STRING , 0x64 }, /* DHCP_PCODE */
58 { OPTION_STRING , 0x65 }, /* DHCP_TCODE */
59 #if ENABLE_FEATURE_UDHCP_RFC3397
60 { OPTION_DNS_STRING | OPTION_LIST , 0x77 }, /* DHCP_DOMAIN_SEARCH */
61 { OPTION_SIP_SERVERS , 0x78 }, /* DHCP_SIP_SERVERS */
63 { OPTION_STATIC_ROUTES | OPTION_LIST , 0x79 }, /* DHCP_STATIC_ROUTES */
64 #if ENABLE_FEATURE_UDHCP_8021Q
65 { OPTION_U16 , 0x84 }, /* DHCP_VLAN_ID */
66 { OPTION_U8 , 0x85 }, /* DHCP_VLAN_PRIORITY */
68 { OPTION_STRING , 0xd1 }, /* DHCP_PXE_CONF_FILE */
69 { OPTION_STRING , 0xd2 }, /* DHCP_PXE_PATH_PREFIX */
70 { OPTION_U32 , 0xd3 }, /* DHCP_REBOOT_TIME */
71 { OPTION_6RD , 0xd4 }, /* DHCP_6RD */
72 { OPTION_STATIC_ROUTES | OPTION_LIST , 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
73 { OPTION_STRING , 0xfc }, /* DHCP_WPAD */
75 /* Options below have no match in dhcp_option_strings[],
76 * are not passed to dhcpc scripts, and cannot be specified
77 * with "option XXX YYY" syntax in dhcpd config file.
78 * These entries are only used internally by udhcp[cd]
79 * to correctly encode options into packets.
82 { OPTION_IP , 0x32 }, /* DHCP_REQUESTED_IP */
83 { OPTION_U8 , 0x35 }, /* DHCP_MESSAGE_TYPE */
84 { OPTION_U16 , 0x39 }, /* DHCP_MAX_SIZE */
85 //looks like these opts will work just fine even without these defs:
86 // { OPTION_STRING , 0x3c }, /* DHCP_VENDOR */
87 // /* not really a string: */
88 // { OPTION_STRING , 0x3d }, /* DHCP_CLIENT_ID */
89 { 0, 0 } /* zeroed terminating entry */
92 /* Used for converting options from incoming packets to env variables
93 * for udhcpc script, and for setting options for udhcpd via
94 * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
96 /* Must match dhcp_optflags[] order */
97 const char dhcp_option_strings[] ALIGN1 =
98 "subnet" "\0" /* DHCP_SUBNET */
99 "timezone" "\0" /* DHCP_TIME_OFFSET */
100 "router" "\0" /* DHCP_ROUTER */
101 // "timesrv" "\0" /* DHCP_TIME_SERVER */
102 // "namesrv" "\0" /* DHCP_NAME_SERVER */
103 "dns" "\0" /* DHCP_DNS_SERVER */
104 // "logsrv" "\0" /* DHCP_LOG_SERVER */
105 // "cookiesrv" "\0" /* DHCP_COOKIE_SERVER */
106 "lprsrv" "\0" /* DHCP_LPR_SERVER */
107 "hostname" "\0" /* DHCP_HOST_NAME */
108 "bootsize" "\0" /* DHCP_BOOT_SIZE */
109 "domain" "\0" /* DHCP_DOMAIN_NAME */
110 "swapsrv" "\0" /* DHCP_SWAP_SERVER */
111 "rootpath" "\0" /* DHCP_ROOT_PATH */
112 "ipttl" "\0" /* DHCP_IP_TTL */
113 "mtu" "\0" /* DHCP_MTU */
114 "broadcast" "\0" /* DHCP_BROADCAST */
115 "routes" "\0" /* DHCP_ROUTES */
116 "nisdomain" "\0" /* DHCP_NIS_DOMAIN */
117 "nissrv" "\0" /* DHCP_NIS_SERVER */
118 "ntpsrv" "\0" /* DHCP_NTP_SERVER */
119 "wins" "\0" /* DHCP_WINS_SERVER */
120 "lease" "\0" /* DHCP_LEASE_TIME */
121 "serverid" "\0" /* DHCP_SERVER_ID */
122 "message" "\0" /* DHCP_ERR_MESSAGE */
123 "tftp" "\0" /* DHCP_TFTP_SERVER_NAME*/
124 "bootfile" "\0" /* DHCP_BOOT_FILE */
125 // "userclass" "\0" /* DHCP_USER_CLASS */
126 "tzstr" "\0" /* DHCP_PCODE */
127 "tzdbstr" "\0" /* DHCP_TCODE */
128 #if ENABLE_FEATURE_UDHCP_RFC3397
129 "search" "\0" /* DHCP_DOMAIN_SEARCH */
130 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
131 // is not handled yet by "string->option" conversion code:
132 "sipsrv" "\0" /* DHCP_SIP_SERVERS */
134 "staticroutes" "\0" /* DHCP_STATIC_ROUTES */
135 #if ENABLE_FEATURE_UDHCP_8021Q
136 "vlanid" "\0" /* DHCP_VLAN_ID */
137 "vlanpriority" "\0" /* DHCP_VLAN_PRIORITY */
139 "pxeconffile" "\0" /* DHCP_PXE_CONF_FILE */
140 "pxepathprefix" "\0" /* DHCP_PXE_PATH_PREFIX */
141 "reboottime" "\0" /* DHCP_REBOOT_TIME */
142 "ip6rd" "\0" /* DHCP_6RD */
143 "msstaticroutes" "\0" /* DHCP_MS_STATIC_ROUTES*/
144 "wpad" "\0" /* DHCP_WPAD */
148 /* Lengths of the option types in binary form.
150 * udhcp_str2optset: to determine how many bytes to allocate.
151 * xmalloc_optname_optval: to estimate string length
152 * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
153 * is the number of elements, multiply it by one element's string width
154 * (len_of_option_as_string[opt_type]) and you know how wide string you need.
156 const uint8_t dhcp_option_lengths[] ALIGN1 = {
158 [OPTION_IP_PAIR] = 8,
159 // [OPTION_BOOLEAN] = 1,
160 [OPTION_STRING] = 1, /* ignored by udhcp_str2optset */
161 [OPTION_STRING_HOST] = 1, /* ignored by udhcp_str2optset */
162 #if ENABLE_FEATURE_UDHCP_RFC3397
163 [OPTION_DNS_STRING] = 1, /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
164 [OPTION_SIP_SERVERS] = 1,
171 /* Just like OPTION_STRING, we use minimum length here */
172 [OPTION_STATIC_ROUTES] = 5,
173 [OPTION_6RD] = 12, /* ignored by udhcp_str2optset */
174 /* The above value was chosen as follows:
175 * len_of_option_as_string[] for this option is >60: it's a string of the form
176 * "32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 ".
177 * Each additional ipv4 address takes 4 bytes in binary option and appends
178 * another "255.255.255.255 " 16-byte string. We can set [OPTION_6RD] = 4
179 * but this severely overestimates string length: instead of 16 bytes,
180 * it adds >60 for every 4 bytes in binary option.
181 * We cheat and declare here that option is in units of 12 bytes.
182 * This adds more than 60 bytes for every three ipv4 addresses - more than enough.
183 * (Even 16 instead of 12 should work, but let's be paranoid).
188 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
189 static void log_option(const char *pfx, const uint8_t *opt)
191 if (dhcp_verbose >= 2) {
192 char buf[256 * 2 + 2];
193 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
194 bb_error_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
198 # define log_option(pfx, opt) ((void)0)
201 unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings)
203 int n = index_in_strings(option_strings, name);
215 d = buf = xzalloc(s - option_strings);
217 while (!(*s == '\0' && s[1] == '\0')) {
218 *d++ = (*s == '\0' ? ' ' : *s);
221 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
225 /* Get an option with bounds checking (warning, result is not aligned) */
226 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
233 FILE_FIELD101 = FILE_FIELD * 0x101,
234 SNAME_FIELD101 = SNAME_FIELD * 0x101,
237 /* option bytes: [code][len][data1][data2]..[dataLEN] */
238 optionptr = packet->options;
239 rem = sizeof(packet->options);
243 bb_error_msg("bad packet, malformed option field");
247 /* DHCP_PADDING and DHCP_END have no [len] byte */
248 if (optionptr[OPT_CODE] == DHCP_PADDING) {
253 if (optionptr[OPT_CODE] == DHCP_END) {
254 if ((overload & FILE_FIELD101) == FILE_FIELD) {
255 /* can use packet->file, and didn't look at it yet */
256 overload |= FILE_FIELD101; /* "we looked at it" */
257 optionptr = packet->file;
258 rem = sizeof(packet->file);
261 if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
262 /* can use packet->sname, and didn't look at it yet */
263 overload |= SNAME_FIELD101; /* "we looked at it" */
264 optionptr = packet->sname;
265 rem = sizeof(packet->sname);
272 goto complain; /* complain and return NULL */
273 len = 2 + optionptr[OPT_LEN];
276 goto complain; /* complain and return NULL */
278 if (optionptr[OPT_CODE] == code) {
279 if (optionptr[OPT_LEN] == 0) {
280 /* So far no valid option with length 0 known.
281 * Having this check means that searching
282 * for DHCP_MESSAGE_TYPE need not worry
283 * that returned pointer might be unsafe
286 goto complain; /* complain and return NULL */
288 log_option("option found", optionptr);
289 return optionptr + OPT_DATA;
292 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
294 overload |= optionptr[OPT_DATA];
300 /* log3 because udhcpc uses it a lot - very noisy */
301 log3("option 0x%02x not found", code);
305 uint8_t* FAST_FUNC udhcp_get_option32(struct dhcp_packet *packet, int code)
307 uint8_t *r = udhcp_get_option(packet, code);
309 if (r[-OPT_DATA + OPT_LEN] != 4)
315 /* Return the position of the 'end' option (no bounds checking) */
316 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
320 while (optionptr[i] != DHCP_END) {
321 if (optionptr[i] != DHCP_PADDING)
322 i += optionptr[i + OPT_LEN] + OPT_DATA-1;
328 /* Add an option (supplied in binary form) to the options.
329 * Option format: [code][len][data1][data2]..[dataLEN]
331 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
334 uint8_t *optionptr = packet->options;
335 unsigned end = udhcp_end_option(optionptr);
337 len = OPT_DATA + addopt[OPT_LEN];
338 /* end position + (option code/length + addopt length) + end option */
339 if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
340 //TODO: learn how to use overflow option if we exhaust packet->options[]
341 bb_error_msg("option 0x%02x did not fit into the packet",
345 log_option("adding option", addopt);
346 memcpy(optionptr + end, addopt, len);
347 optionptr[end + len] = DHCP_END;
350 #if ENABLE_UDHCPC || ENABLE_UDHCPD
351 /* Add an one to four byte option to a packet */
352 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
354 const struct dhcp_optflag *dh;
356 for (dh = dhcp_optflags; dh->code; dh++) {
357 if (dh->code == code) {
358 uint8_t option[6], len;
360 option[OPT_CODE] = code;
361 len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
362 option[OPT_LEN] = len;
364 data <<= 8 * (4 - len);
365 /* Assignment is unaligned! */
366 move_to_unaligned32(&option[OPT_DATA], data);
367 udhcp_add_binary_option(packet, option);
372 bb_error_msg("can't add option 0x%02x", code);
376 /* Find option 'code' in opt_list */
377 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
379 while (opt_list && opt_list->data[OPT_CODE] < code)
380 opt_list = opt_list->next;
382 if (opt_list && opt_list->data[OPT_CODE] == code)
387 /* Parse string to IP in network order */
388 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
390 len_and_sockaddr *lsa;
392 lsa = host_and_af2sockaddr(str, 0, AF_INET);
395 /* arg maybe unaligned */
396 move_to_unaligned32((uint32_t*)arg, lsa->u.sin.sin_addr.s_addr);
402 * Parse string option representation to binary form and add it to opt_list.
403 * Called to parse "udhcpc -x OPTNAME:OPTVAL"
404 * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
406 /* helper: add an option to the opt_list */
408 #define attach_option(opt_list, optflag, buffer, length, dhcpv6) \
409 attach_option(opt_list, optflag, buffer, length)
411 static NOINLINE void attach_option(
412 struct option_set **opt_list,
413 const struct dhcp_optflag *optflag,
418 IF_NOT_UDHCPC6(bool dhcpv6 = 0;)
419 struct option_set *existing;
420 char *allocated = NULL;
422 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
424 allocated = xstrdup(buffer); /* more than enough */
425 end = hex2bin(allocated, buffer, 255);
427 bb_error_msg_and_die("malformed hex string '%s'", buffer);
428 length = end - allocated;
431 #if ENABLE_FEATURE_UDHCP_RFC3397
432 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
433 /* reuse buffer and length for RFC1035-formatted string */
434 allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
438 existing = udhcp_find_option(*opt_list, optflag->code);
440 struct option_set *new, **curr;
442 /* make a new option */
443 log2("attaching option %02x to list", optflag->code);
444 new = xmalloc(sizeof(*new));
446 new->data = xmalloc(length + OPT_DATA);
447 new->data[OPT_CODE] = optflag->code;
448 new->data[OPT_LEN] = length;
449 memcpy(new->data + OPT_DATA, buffer, length);
451 new->data = xmalloc(length + D6_OPT_DATA);
452 new->data[D6_OPT_CODE] = optflag->code >> 8;
453 new->data[D6_OPT_CODE + 1] = optflag->code & 0xff;
454 new->data[D6_OPT_LEN] = length >> 8;
455 new->data[D6_OPT_LEN + 1] = length & 0xff;
456 memcpy(new->data + D6_OPT_DATA, buffer,
461 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
462 curr = &(*curr)->next;
469 if (optflag->flags & OPTION_LIST) {
472 /* add it to an existing option */
473 log2("attaching option %02x to existing member of list", optflag->code);
474 old_len = existing->data[OPT_LEN];
475 if (old_len + length < 255) {
476 /* actually 255 is ok too, but adding a space can overlow it */
478 existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
479 // So far dhcp_optflags[] has no OPTION_STRING[_HOST] | OPTION_LIST items
481 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING
482 || (optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING_HOST
484 /* add space separator between STRING options in a list */
485 existing->data[OPT_DATA + old_len] = ' ';
490 memcpy(existing->data + OPT_DATA + old_len, buffer, length);
491 existing->data[OPT_LEN] = old_len + length;
492 } /* else, ignore the data, we could put this in a second option in the future */
493 } /* else, ignore the new data */
499 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg,
500 const struct dhcp_optflag *optflags, const char *option_strings,
503 struct option_set **opt_list = arg;
506 const struct dhcp_optflag *optflag;
507 struct dhcp_optflag userdef_optflag;
510 /* IP_PAIR needs 8 bytes, STATIC_ROUTES needs 9 max */
511 char buffer[9] ALIGNED(4);
512 uint16_t *result_u16 = (uint16_t *) buffer;
513 uint32_t *result_u32 = (uint32_t *) buffer;
515 /* Cheat, the only *const* str possible is "" */
516 str = (char *) const_str;
517 opt = strtok(str, " \t=:");
521 optcode = bb_strtou(opt, NULL, 0);
522 if (!errno && optcode < 255) {
523 /* Raw (numeric) option code.
524 * Initially assume binary (hex-str), but if "str" or 'str'
525 * is seen later, switch to STRING.
527 userdef_optflag.flags = OPTION_BIN;
528 userdef_optflag.code = optcode;
529 optflag = &userdef_optflag;
531 optflag = &optflags[udhcp_option_idx(opt, option_strings)];
534 /* Loop to handle OPTION_LIST case, else execute just once */
540 if (optflag->flags == OPTION_BIN) {
541 val = strtok(NULL, ""); /* do not split "'q w e'" */
544 val = strtok(NULL, ", \t");
548 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
550 opt = buffer; /* new meaning for variable opt */
552 switch (optflag->flags & OPTION_TYPE_MASK) {
554 retval = udhcp_str2nip(val, buffer);
557 retval = udhcp_str2nip(val, buffer);
558 val = strtok(NULL, ", \t/-");
562 retval = udhcp_str2nip(val, buffer + 4);
566 case OPTION_STRING_HOST:
567 #if ENABLE_FEATURE_UDHCP_RFC3397
568 case OPTION_DNS_STRING:
570 length = strnlen(val, 254);
576 // case OPTION_BOOLEAN: {
577 // static const char no_yes[] ALIGN1 = "no\0yes\0";
578 // buffer[0] = retval = index_in_strings(no_yes, val);
579 // retval++; /* 0 - bad; 1: "no" 2: "yes" */
583 buffer[0] = bb_strtou32(val, NULL, 0);
584 retval = (errno == 0);
586 /* htonX are macros in older libc's, using temp var
587 * in code below for safety */
588 /* TODO: use bb_strtoX? */
590 uint32_t tmp = bb_strtou32(val, NULL, 0);
591 *result_u16 = htons(tmp);
592 retval = (errno == 0 /*&& tmp < 0x10000*/);
595 // case OPTION_S16: {
596 // long tmp = bb_strtoi32(val, NULL, 0);
597 // *result_u16 = htons(tmp);
598 // retval = (errno == 0);
602 uint32_t tmp = bb_strtou32(val, NULL, 0);
603 *result_u32 = htonl(tmp);
604 retval = (errno == 0);
608 int32_t tmp = bb_strtoi32(val, NULL, 0);
609 *result_u32 = htonl(tmp);
610 retval = (errno == 0);
613 case OPTION_STATIC_ROUTES: {
614 /* Input: "a.b.c.d/m" */
615 /* Output: mask(1 byte),pfx(0-4 bytes),gw(4 bytes) */
617 char *slash = strchr(val, '/');
620 retval = udhcp_str2nip(val, buffer + 1);
621 buffer[0] = mask = bb_strtou(slash + 1, NULL, 10);
622 val = strtok(NULL, ", \t/-");
623 if (!val || mask > 32 || errno)
626 length = ((mask + 7) >> 3) + 5;
627 retval = udhcp_str2nip(val, buffer + (length - 4));
633 /* Raw (numeric) option code. Is it a string? */
634 if (val[0] == '"' || val[0] == '\'') {
636 char *end = last_char_is(val + 1, delim);
640 userdef_optflag.flags = OPTION_STRING;
641 goto case_OPTION_STRING;
644 /* No: hex-str option, handled in attach_option() */
653 attach_option(opt_list, optflag, opt, length, dhcpv6);
654 } while (retval && (optflag->flags & OPTION_LIST));
659 /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */
660 int FAST_FUNC sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip)
662 char hexstrbuf[16 * 2];
663 bin2hex(hexstrbuf, (void*)ip, 16);
664 return sprintf(dest, /* "%s" */
665 "%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s",