/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include <sys/queue.h> #include <sys/types.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/un.h> #include <sys/uio.h> #include <net/if.h> #include <net/if_dl.h> #include <net/if_types.h> #include <net/ethernet.h> #include <netinet/in.h> #include <netinet/ip6.h> #include <netinet/icmp6.h> #include <netinet6/in6_var.h> #include <netinet6/nd6.h> #include <arpa/inet.h> #include <fcntl.h> #include <errno.h> #include <inttypes.h> #include <netdb.h> #include <unistd.h> #include <string.h> #include <stdarg.h> #include <stdio.h> #include <stdlib.h> #include <stdarg.h> #include <syslog.h> #include <time.h> #include <err.h> #include "pathnames.h" #include "rtadvd.h" #include "if.h" #include "timer_subr.h" #include "timer.h" #include "control.h" #include "control_client.h" #define RA_IFSTATUS_INACTIVE 0 #define RA_IFSTATUS_RA_RECV 1 #define RA_IFSTATUS_RA_SEND 2 static int vflag = LOG_ERR; static void usage(void); static int action_propset(char *); static int action_propget(char *, struct ctrl_msg_pl *); static int action_plgeneric(int, char *, char *); static int action_enable(int, char **); static int action_disable(int, char **); static int action_reload(int, char **); static int action_echo(int, char **); static int action_version(int, char **); static int action_shutdown(int, char **); static int action_show(int, char **); static int action_show_prefix(struct prefix *); static int action_show_rtinfo(struct rtinfo *); static int action_show_rdnss(void *); static int action_show_dnssl(void *); static int csock_client_open(struct sockinfo *); static size_t dname_labeldec(char *, size_t, const char *); static void mysyslog(int, const char *, ...); static const char *rtpref_str[] = { "medium", /* 00 */ "high", /* 01 */ "rsv", /* 10 */ "low" /* 11 */ }; static struct dispatch_table { const char *dt_comm; int (*dt_act)(int, char **); } dtable[] = { { "show", action_show }, { "reload", action_reload }, { "shutdown", action_shutdown }, { "enable", action_enable }, { "disable", action_disable }, { NULL, NULL }, { "echo", action_echo }, { "version", action_version }, { NULL, NULL }, }; static char errmsgbuf[1024]; static char *errmsg = NULL; static void mysyslog(int priority, const char * restrict fmt, ...) { va_list ap; if (vflag >= priority) { va_start(ap, fmt); vfprintf(stderr, fmt, ap); fprintf(stderr, "\n"); va_end(ap); } } static void usage(void) { int i; for (i = 0; (size_t)i < sizeof(dtable)/sizeof(dtable[0]); i++) { if (dtable[i].dt_comm == NULL) break; printf("%s\n", dtable[i].dt_comm); } exit(1); } int main(int argc, char *argv[]) { int i; int ch; int (*action)(int, char **) = NULL; int error; while ((ch = getopt(argc, argv, "Dv")) != -1) { switch (ch) { case 'D': vflag = LOG_DEBUG; break; case 'v': vflag++; break; default: usage(); } } argc -= optind; argv += optind; if (argc == 0) usage(); for (i = 0; (size_t)i < sizeof(dtable)/sizeof(dtable[0]); i++) { if (dtable[i].dt_comm == NULL || strcmp(dtable[i].dt_comm, argv[0]) == 0) { action = dtable[i].dt_act; break; } } if (action == NULL) usage(); error = (dtable[i].dt_act)(--argc, ++argv); if (error) { fprintf(stderr, "%s failed", dtable[i].dt_comm); if (errmsg != NULL) fprintf(stderr, ": %s", errmsg); fprintf(stderr, ".\n"); } return (error); } static int csock_client_open(struct sockinfo *s) { struct sockaddr_un sun; if ((s->si_fd = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) err(1, "cannot open control socket."); memset(&sun, 0, sizeof(sun)); sun.sun_family = AF_UNIX; sun.sun_len = sizeof(sun); strlcpy(sun.sun_path, s->si_name, sizeof(sun.sun_path)); if (connect(s->si_fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) err(1, "connect: %s", s->si_name); mysyslog(LOG_DEBUG, "<%s> connected to %s", __func__, sun.sun_path); return (0); } static int action_plgeneric(int action, char *plstr, char *buf) { struct ctrl_msg_hdr *cm; struct ctrl_msg_pl cp; struct sockinfo *s; char *msg; char *p; char *q; s = &ctrlsock; csock_client_open(s); cm = (struct ctrl_msg_hdr *)buf; msg = (char *)buf + sizeof(*cm); cm->cm_version = CM_VERSION; cm->cm_type = action; cm->cm_len = sizeof(*cm); if (plstr != NULL) { memset(&cp, 0, sizeof(cp)); p = strchr(plstr, ':'); q = strchr(plstr, '='); if (p != NULL && q != NULL && p > q) return (1); if (p == NULL) { /* No : */ cp.cp_ifname = NULL; cp.cp_key = plstr; } else if (p == plstr) { /* empty */ cp.cp_ifname = NULL; cp.cp_key = plstr + 1; } else { *p++ = '\0'; cp.cp_ifname = plstr; cp.cp_key = p; } if (q == NULL) cp.cp_val = NULL; else { *q++ = '\0'; cp.cp_val = q; } cm->cm_len += cm_pl2bin(msg, &cp); mysyslog(LOG_DEBUG, "<%s> key=%s, val_len=%d, ifname=%s", __func__,cp.cp_key, cp.cp_val_len, cp.cp_ifname); } return (cm_handler_client(s->si_fd, CM_STATE_MSG_DISPATCH, buf)); } static int action_propget(char *argv, struct ctrl_msg_pl *cp) { int error; struct ctrl_msg_hdr *cm; char buf[CM_MSG_MAXLEN]; char *msg; memset(cp, 0, sizeof(*cp)); cm = (struct ctrl_msg_hdr *)buf; msg = (char *)buf + sizeof(*cm); error = action_plgeneric(CM_TYPE_REQ_GET_PROP, argv, buf); if (error || cm->cm_len <= sizeof(*cm)) return (1); cm_bin2pl(msg, cp); mysyslog(LOG_DEBUG, "<%s> type=%d, len=%d", __func__, cm->cm_type, cm->cm_len); mysyslog(LOG_DEBUG, "<%s> key=%s, val_len=%d, ifname=%s", __func__,cp->cp_key, cp->cp_val_len, cp->cp_ifname); return (0); } static int action_propset(char *argv) { char buf[CM_MSG_MAXLEN]; return (action_plgeneric(CM_TYPE_REQ_SET_PROP, argv, buf)); } static int action_disable(int argc, char **argv) { char *action_argv; char argv_disable[IFNAMSIZ + sizeof(":disable=")]; int i; int error; if (argc < 1) return (1); error = 0; for (i = 0; i < argc; i++) { sprintf(argv_disable, "%s:disable=", argv[i]); action_argv = argv_disable; error += action_propset(action_argv); } return (error); } static int action_enable(int argc, char **argv) { char *action_argv; char argv_enable[IFNAMSIZ + sizeof(":enable=")]; int i; int error; if (argc < 1) return (1); error = 0; for (i = 0; i < argc; i++) { sprintf(argv_enable, "%s:enable=", argv[i]); action_argv = argv_enable; error += action_propset(action_argv); } return (error); } static int action_reload(int argc, char **argv) { char *action_argv; char argv_reload[IFNAMSIZ + sizeof(":reload=")]; int i; int error; if (argc == 0) { action_argv = strdup(":reload="); return (action_propset(action_argv)); } error = 0; for (i = 0; i < argc; i++) { sprintf(argv_reload, "%s:reload=", argv[i]); action_argv = argv_reload; error += action_propset(action_argv); } return (error); } static int action_echo(int argc __unused, char **argv __unused) { char *action_argv; action_argv = strdup("echo"); return (action_propset(action_argv)); } static int action_shutdown(int argc __unused, char **argv __unused) { char *action_argv; action_argv = strdup("shutdown"); return (action_propset(action_argv)); } /* XXX */ static int action_version(int argc __unused, char **argv __unused) { char *action_argv; struct ctrl_msg_pl cp; int error; action_argv = strdup(":version="); error = action_propget(action_argv, &cp); if (error) return (error); printf("version=%s\n", cp.cp_val); return (0); } static int action_show(int argc, char **argv) { char *action_argv; char argv_ifilist[sizeof(":ifilist=")] = ":ifilist="; char argv_ifi[IFNAMSIZ + sizeof(":ifi=")]; char argv_rai[IFNAMSIZ + sizeof(":rai=")]; char argv_rti[IFNAMSIZ + sizeof(":rti=")]; char argv_pfx[IFNAMSIZ + sizeof(":pfx=")]; char argv_ifi_ra_timer[IFNAMSIZ + sizeof(":ifi_ra_timer=")]; char argv_rdnss[IFNAMSIZ + sizeof(":rdnss=")]; char argv_dnssl[IFNAMSIZ + sizeof(":dnssl=")]; char ssbuf[SSBUFLEN]; struct timespec now, ts0, ts; struct ctrl_msg_pl cp; struct ifinfo *ifi; TAILQ_HEAD(, ifinfo) ifl = TAILQ_HEAD_INITIALIZER(ifl); char *endp; char *p; int error; int i; int len; if (argc == 0) { action_argv = argv_ifilist; error = action_propget(action_argv, &cp); if (error) return (error); p = cp.cp_val; endp = p + cp.cp_val_len; while (p < endp) { ifi = malloc(sizeof(*ifi)); if (ifi == NULL) return (1); memset(ifi, 0, sizeof(*ifi)); strcpy(ifi->ifi_ifname, p); ifi->ifi_ifindex = if_nametoindex(ifi->ifi_ifname); TAILQ_INSERT_TAIL(&ifl, ifi, ifi_next); p += strlen(ifi->ifi_ifname) + 1; } } else { for (i = 0; i < argc; i++) { ifi = malloc(sizeof(*ifi)); if (ifi == NULL) return (1); memset(ifi, 0, sizeof(*ifi)); strcpy(ifi->ifi_ifname, argv[i]); ifi->ifi_ifindex = if_nametoindex(ifi->ifi_ifname); if (ifi->ifi_ifindex == 0) { sprintf(errmsgbuf, "invalid interface %s", ifi->ifi_ifname); errmsg = errmsgbuf; return (1); } TAILQ_INSERT_TAIL(&ifl, ifi, ifi_next); } } clock_gettime(CLOCK_REALTIME_FAST, &now); clock_gettime(CLOCK_MONOTONIC_FAST, &ts); TS_SUB(&now, &ts, &ts0); TAILQ_FOREACH(ifi, &ifl, ifi_next) { struct ifinfo *ifi_s; struct rtadvd_timer *rat; struct rainfo *rai; struct rtinfo *rti; struct prefix *pfx; int c; int ra_ifstatus; sprintf(argv_ifi, "%s:ifi=", ifi->ifi_ifname); action_argv = argv_ifi; error = action_propget(action_argv, &cp); if (error) return (error); ifi_s = (struct ifinfo *)cp.cp_val; if (!(ifi_s->ifi_persist) && vflag < LOG_NOTICE) continue; printf("%s: flags=<", ifi->ifi_ifname); c = 0; if (ifi_s->ifi_ifindex == 0) c += printf("NONEXISTENT"); else c += printf("%s", (ifi_s->ifi_flags & IFF_UP) ? "UP" : "DOWN"); switch (ifi_s->ifi_state) { case IFI_STATE_CONFIGURED: c += printf("%s%s", (c) ? "," : "", "CONFIGURED"); break; case IFI_STATE_TRANSITIVE: c += printf("%s%s", (c) ? "," : "", "TRANSITIVE"); break; } if (ifi_s->ifi_persist) c += printf("%s%s", (c) ? "," : "", "PERSIST"); printf(">"); ra_ifstatus = RA_IFSTATUS_INACTIVE; if ((ifi_s->ifi_flags & IFF_UP) && ((ifi_s->ifi_state == IFI_STATE_CONFIGURED) || (ifi_s->ifi_state == IFI_STATE_TRANSITIVE))) { /* * RA_RECV: ND6_IFF_ACCEPT_RTADV * RA_SEND: ip6.forwarding */ if (ifi_s->ifi_nd_flags & ND6_IFF_ACCEPT_RTADV) ra_ifstatus = RA_IFSTATUS_RA_RECV; else if (getinet6sysctl(IPV6CTL_FORWARDING)) ra_ifstatus = RA_IFSTATUS_RA_SEND; else ra_ifstatus = RA_IFSTATUS_INACTIVE; } c = 0; printf(" status=<"); if (ra_ifstatus == RA_IFSTATUS_INACTIVE) printf("%s%s", (c) ? "," : "", "INACTIVE"); else if (ra_ifstatus == RA_IFSTATUS_RA_RECV) printf("%s%s", (c) ? "," : "", "RA_RECV"); else if (ra_ifstatus == RA_IFSTATUS_RA_SEND) printf("%s%s", (c) ? "," : "", "RA_SEND"); printf("> "); switch (ifi_s->ifi_state) { case IFI_STATE_CONFIGURED: case IFI_STATE_TRANSITIVE: break; default: printf("\n"); continue; } printf("mtu %d\n", ifi_s->ifi_phymtu); sprintf(argv_rai, "%s:rai=", ifi->ifi_ifname); action_argv = argv_rai; error = action_propget(action_argv, &cp); if (error) continue; rai = (struct rainfo *)cp.cp_val; printf("\tDefaultLifetime: %s", sec2str(rai->rai_lifetime, ssbuf)); if (ra_ifstatus != RA_IFSTATUS_RA_SEND && rai->rai_lifetime == 0) printf(" (RAs will be sent with zero lifetime)"); printf("\n"); printf("\tMinAdvInterval/MaxAdvInterval: "); printf("%s/", sec2str(rai->rai_mininterval, ssbuf)); printf("%s\n", sec2str(rai->rai_maxinterval, ssbuf)); if (rai->rai_linkmtu) printf("\tAdvLinkMTU: %d", rai->rai_linkmtu); else printf("\tAdvLinkMTU: <none>"); printf(", "); printf("Flags: "); if (rai->rai_managedflg || rai->rai_otherflg) { printf("%s", rai->rai_managedflg ? "M" : ""); printf("%s", rai->rai_otherflg ? "O" : ""); } else printf("<none>"); printf(", "); printf("Preference: %s\n", rtpref_str[(rai->rai_rtpref >> 3) & 0xff]); printf("\tReachableTime: %s, ", sec2str(rai->rai_reachabletime, ssbuf)); printf("RetransTimer: %s, " "CurHopLimit: %d\n", sec2str(rai->rai_retranstimer, ssbuf), rai->rai_hoplimit); printf("\tAdvIfPrefixes: %s\n", rai->rai_advifprefix ? "yes" : "no"); /* RA timer */ rat = NULL; if (ifi_s->ifi_ra_timer != NULL) { sprintf(argv_ifi_ra_timer, "%s:ifi_ra_timer=", ifi->ifi_ifname); action_argv = argv_ifi_ra_timer; error = action_propget(action_argv, &cp); if (error) return (error); rat = (struct rtadvd_timer *)cp.cp_val; } printf("\tNext RA send: "); if (rat == NULL) printf("never\n"); else { ts.tv_sec = rat->rat_tm.tv_sec + ts0.tv_sec; printf("%s", ctime(&ts.tv_sec)); } printf("\tLast RA send: "); if (ifi_s->ifi_ra_lastsent.tv_sec == 0) printf("never\n"); else { ts.tv_sec = ifi_s->ifi_ra_lastsent.tv_sec + ts0.tv_sec; printf("%s", ctime(&ts.tv_sec)); } if (rai->rai_clockskew) printf("\tClock skew: %" PRIu16 "sec\n", rai->rai_clockskew); if (vflag < LOG_WARNING) continue; /* route information */ sprintf(argv_rti, "%s:rti=", ifi->ifi_ifname); action_argv = argv_rti; error = action_propget(action_argv, &cp); if (error) return (error); rti = (struct rtinfo *)cp.cp_val; len = cp.cp_val_len / sizeof(*rti); if (len > 0) { printf("\tRoute Info:\n"); for (i = 0; i < len; i++) action_show_rtinfo(&rti[i]); } /* prefix information */ sprintf(argv_pfx, "%s:pfx=", ifi->ifi_ifname); action_argv = argv_pfx; error = action_propget(action_argv, &cp); if (error) continue; pfx = (struct prefix *)cp.cp_val; len = cp.cp_val_len / sizeof(*pfx); if (len > 0) { printf("\tPrefixes (%d):\n", len); for (i = 0; i < len; i++) action_show_prefix(&pfx[i]); } /* RDNSS information */ sprintf(argv_rdnss, "%s:rdnss=", ifi->ifi_ifname); action_argv = argv_rdnss; error = action_propget(action_argv, &cp); if (error) continue; len = *((uint16_t *)cp.cp_val); if (len > 0) { printf("\tRDNSS entries:\n"); action_show_rdnss(cp.cp_val); } /* DNSSL information */ sprintf(argv_dnssl, "%s:dnssl=", ifi->ifi_ifname); action_argv = argv_dnssl; error = action_propget(action_argv, &cp); if (error) continue; len = *((uint16_t *)cp.cp_val); if (len > 0) { printf("\tDNSSL entries:\n"); action_show_dnssl(cp.cp_val); } if (vflag < LOG_NOTICE) continue; printf("\n"); printf("\tCounters\n" "\t RA burst counts: %" PRIu16 " (interval: %s)\n" "\t RS wait counts: %" PRIu16 "\n", ifi_s->ifi_burstcount, sec2str(ifi_s->ifi_burstinterval, ssbuf), ifi_s->ifi_rs_waitcount); printf("\tOutputs\n" "\t RA: %" PRIu64 "\n", ifi_s->ifi_raoutput); printf("\tInputs\n" "\t RA: %" PRIu64 " (normal)\n" "\t RA: %" PRIu64 " (inconsistent)\n" "\t RS: %" PRIu64 "\n", ifi_s->ifi_rainput, ifi_s->ifi_rainconsistent, ifi_s->ifi_rsinput); printf("\n"); #if 0 /* Not implemented yet */ printf("\tReceived RAs:\n"); #endif } return (0); } static int action_show_rtinfo(struct rtinfo *rti) { char ntopbuf[INET6_ADDRSTRLEN]; char ssbuf[SSBUFLEN]; printf("\t %s/%d (pref: %s, ltime: %s)\n", inet_ntop(AF_INET6, &rti->rti_prefix, ntopbuf, sizeof(ntopbuf)), rti->rti_prefixlen, rtpref_str[0xff & (rti->rti_rtpref >> 3)], (rti->rti_ltime == ND6_INFINITE_LIFETIME) ? "infinity" : sec2str(rti->rti_ltime, ssbuf)); return (0); } static int action_show_prefix(struct prefix *pfx) { char ntopbuf[INET6_ADDRSTRLEN]; char ssbuf[SSBUFLEN]; struct timespec now; clock_gettime(CLOCK_MONOTONIC_FAST, &now); printf("\t %s/%d", inet_ntop(AF_INET6, &pfx->pfx_prefix, ntopbuf, sizeof(ntopbuf)), pfx->pfx_prefixlen); printf(" ("); switch (pfx->pfx_origin) { case PREFIX_FROM_KERNEL: printf("KERNEL"); break; case PREFIX_FROM_CONFIG: printf("CONFIG"); break; case PREFIX_FROM_DYNAMIC: printf("DYNAMIC"); break; } printf(","); printf(" vltime=%s", (pfx->pfx_validlifetime == ND6_INFINITE_LIFETIME) ? "infinity" : sec2str(pfx->pfx_validlifetime, ssbuf)); if (pfx->pfx_vltimeexpire > 0) printf("(expire: %s)", ((long)pfx->pfx_vltimeexpire > now.tv_sec) ? sec2str(pfx->pfx_vltimeexpire - now.tv_sec, ssbuf) : "0"); printf(","); printf(" pltime=%s", (pfx->pfx_preflifetime == ND6_INFINITE_LIFETIME) ? "infinity" : sec2str(pfx->pfx_preflifetime, ssbuf)); if (pfx->pfx_pltimeexpire > 0) printf("(expire %s)", ((long)pfx->pfx_pltimeexpire > now.tv_sec) ? sec2str(pfx->pfx_pltimeexpire - now.tv_sec, ssbuf) : "0"); printf(","); printf(" flags="); if (pfx->pfx_onlinkflg || pfx->pfx_autoconfflg) { printf("%s", pfx->pfx_onlinkflg ? "L" : ""); printf("%s", pfx->pfx_autoconfflg ? "A" : ""); } else printf("<none>"); if (pfx->pfx_timer) { struct timespec *rest; rest = rtadvd_timer_rest(pfx->pfx_timer); if (rest) { /* XXX: what if not? */ printf(" expire=%s", sec2str(rest->tv_sec, ssbuf)); } } printf(")\n"); return (0); } static int action_show_rdnss(void *msg) { struct rdnss *rdn; struct rdnss_addr *rda; uint16_t *rdn_cnt; uint16_t *rda_cnt; int i; int j; char *p; uint32_t ltime; char ntopbuf[INET6_ADDRSTRLEN]; char ssbuf[SSBUFLEN]; p = msg; rdn_cnt = (uint16_t *)p; p += sizeof(*rdn_cnt); if (*rdn_cnt > 0) { for (i = 0; i < *rdn_cnt; i++) { rdn = (struct rdnss *)p; ltime = rdn->rd_ltime; p += sizeof(*rdn); rda_cnt = (uint16_t *)p; p += sizeof(*rda_cnt); if (*rda_cnt > 0) for (j = 0; j < *rda_cnt; j++) { rda = (struct rdnss_addr *)p; printf("\t %s (ltime=%s)\n", inet_ntop(AF_INET6, &rda->ra_dns, ntopbuf, sizeof(ntopbuf)), sec2str(ltime, ssbuf)); p += sizeof(*rda); } } } return (0); } static int action_show_dnssl(void *msg) { struct dnssl *dns; struct dnssl_addr *dna; uint16_t *dns_cnt; uint16_t *dna_cnt; int i; int j; char *p; uint32_t ltime; char hbuf[NI_MAXHOST]; char ssbuf[SSBUFLEN]; p = msg; dns_cnt = (uint16_t *)p; p += sizeof(*dns_cnt); if (*dns_cnt > 0) { for (i = 0; i < *dns_cnt; i++) { dns = (struct dnssl *)p; ltime = dns->dn_ltime; p += sizeof(*dns); dna_cnt = (uint16_t *)p; p += sizeof(*dna_cnt); if (*dna_cnt > 0) for (j = 0; j < *dna_cnt; j++) { dna = (struct dnssl_addr *)p; dname_labeldec(hbuf, sizeof(hbuf), dna->da_dom); printf("\t %s (ltime=%s)\n", hbuf, sec2str(ltime, ssbuf)); p += sizeof(*dna); } } } return (0); } /* Decode domain name label encoding in RFC 1035 Section 3.1 */ static size_t dname_labeldec(char *dst, size_t dlen, const char *src) { size_t len; const char *src_origin; const char *src_last; const char *dst_origin; src_origin = src; src_last = strchr(src, '\0'); dst_origin = dst; memset(dst, '\0', dlen); while (src && (len = (uint8_t)(*src++) & 0x3f) && (src + len) <= src_last) { if (dst != dst_origin) *dst++ = '.'; mysyslog(LOG_DEBUG, "<%s> labellen = %zd", __func__, len); memcpy(dst, src, len); src += len; dst += len; } *dst = '\0'; return (src - src_origin); }