/** * Copyright (C) 2012-2014 Steven Barth * Copyright (C) 2017-2018 Hans Dedecker * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License v2 as published by * the Free Software Foundation. * * 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. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include "odhcp6c.h" static const char hexdigits[] = "0123456789abcdef"; static const int8_t hexvals[] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -2, -1, -1, -2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, }; static char action[16] = ""; static char *argv[4] = {NULL, NULL, action, NULL}; static volatile pid_t running = 0; static time_t started; static void script_sighandle(int signal) { if (signal == SIGCHLD) { pid_t child; while ((child = waitpid(-1, NULL, WNOHANG)) > 0) if (running == child) running = 0; } } int script_init(const char *path, const char *ifname) { argv[0] = (char*)path; argv[1] = (char*)ifname; signal(SIGCHLD, script_sighandle); return 0; } ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src) { size_t c; for (c = 0; c < len && src[0] && src[1]; ++c) { int8_t x = (int8_t)*src++; int8_t y = (int8_t)*src++; if (x < 0 || (x = hexvals[x]) < 0 || y < 0 || (y = hexvals[y]) < 0) return -1; dst[c] = x << 4 | y; while (((int8_t)*src) < 0 || (*src && hexvals[(uint8_t)*src] < 0)) src++; } return c; } static void script_hexlify(char *dst, const uint8_t *src, size_t len) { for (size_t i = 0; i < len; ++i) { *dst++ = hexdigits[src[i] >> 4]; *dst++ = hexdigits[src[i] & 0x0f]; } *dst = 0; } static void ipv6_to_env(const char *name, const struct in6_addr *addr, size_t cnt) { size_t buf_len = strlen(name); char *buf = realloc(NULL, cnt * INET6_ADDRSTRLEN + buf_len + 2); memcpy(buf, name, buf_len); buf[buf_len++] = '='; for (size_t i = 0; i < cnt; ++i) { inet_ntop(AF_INET6, &addr[i], &buf[buf_len], INET6_ADDRSTRLEN); buf_len += strlen(&buf[buf_len]); buf[buf_len++] = ' '; } if (buf[buf_len - 1] == ' ') buf_len--; buf[buf_len] = '\0'; putenv(buf); } static void fqdn_to_env(const char *name, const uint8_t *fqdn, size_t len) { size_t buf_len = strlen(name); size_t buf_size = len + buf_len + 2; const uint8_t *fqdn_end = fqdn + len; char *buf = realloc(NULL, len + buf_len + 2); memcpy(buf, name, buf_len); buf[buf_len++] = '='; while (fqdn < fqdn_end) { int l = dn_expand(fqdn, fqdn_end, fqdn, &buf[buf_len], buf_size - buf_len); if (l <= 0) break; fqdn += l; buf_len += strlen(&buf[buf_len]); buf[buf_len++] = ' '; } if (buf[buf_len - 1] == ' ') buf_len--; buf[buf_len] = '\0'; putenv(buf); } static void bin_to_env(uint8_t *opts, size_t len) { uint8_t *oend = opts + len, *odata; uint16_t otype, olen; dhcpv6_for_each_option(opts, oend, otype, olen, odata) { char *buf = realloc(NULL, 14 + (olen * 2)); size_t buf_len = 0; snprintf(buf, 14, "OPTION_%hu=", otype); buf_len += strlen(buf); script_hexlify(&buf[buf_len], odata, olen); putenv(buf); } } enum entry_type { ENTRY_ADDRESS, ENTRY_HOST, ENTRY_ROUTE, ENTRY_PREFIX }; static void entry_to_env(const char *name, const void *data, size_t len, enum entry_type type) { size_t buf_len = strlen(name); const struct odhcp6c_entry *e = data; // Worst case: ENTRY_PREFIX with iaid != 1 and exclusion const size_t max_entry_len = (INET6_ADDRSTRLEN-1 + 5 + 22 + 15 + 10 + INET6_ADDRSTRLEN-1 + 11 + 1); char *buf = realloc(NULL, buf_len + 2 + (len / sizeof(*e)) * max_entry_len); memcpy(buf, name, buf_len); buf[buf_len++] = '='; for (size_t i = 0; i < len / sizeof(*e); ++i) { inet_ntop(AF_INET6, &e[i].target, &buf[buf_len], INET6_ADDRSTRLEN); buf_len += strlen(&buf[buf_len]); if (type != ENTRY_HOST) { snprintf(&buf[buf_len], 6, "/%"PRIu16, e[i].length); buf_len += strlen(&buf[buf_len]); if (type == ENTRY_ROUTE) { buf[buf_len++] = ','; if (!IN6_IS_ADDR_UNSPECIFIED(&e[i].router)) { inet_ntop(AF_INET6, &e[i].router, &buf[buf_len], INET6_ADDRSTRLEN); buf_len += strlen(&buf[buf_len]); } snprintf(&buf[buf_len], 23, ",%u,%u", e[i].valid, e[i].priority); buf_len += strlen(&buf[buf_len]); } else { snprintf(&buf[buf_len], 23, ",%u,%u", e[i].preferred, e[i].valid); buf_len += strlen(&buf[buf_len]); } if (type == ENTRY_PREFIX && ntohl(e[i].iaid) != 1) { snprintf(&buf[buf_len], 16, ",class=%08x", ntohl(e[i].iaid)); buf_len += strlen(&buf[buf_len]); } if (type == ENTRY_PREFIX && e[i].priority) { // priority and router are abused for prefix exclusion snprintf(&buf[buf_len], 11, ",excluded="); buf_len += strlen(&buf[buf_len]); inet_ntop(AF_INET6, &e[i].router, &buf[buf_len], INET6_ADDRSTRLEN); buf_len += strlen(&buf[buf_len]); snprintf(&buf[buf_len], 12, "/%u", e[i].priority); buf_len += strlen(&buf[buf_len]); } } buf[buf_len++] = ' '; } if (buf[buf_len - 1] == ' ') buf_len--; buf[buf_len] = '\0'; putenv(buf); } static void search_to_env(const char *name, const uint8_t *start, size_t len) { size_t buf_len = strlen(name); char *buf = realloc(NULL, buf_len + 2 + len); char *c = mempcpy(buf, name, buf_len); *c++ = '='; for (struct odhcp6c_entry *e = (struct odhcp6c_entry*)start; (uint8_t*)e < &start[len] && (uint8_t*)odhcp6c_next_entry(e) <= &start[len]; e = odhcp6c_next_entry(e)) { c = mempcpy(c, e->auxtarget, e->auxlen); *c++ = ' '; } if (c[-1] == ' ') c--; *c = '\0'; putenv(buf); } static void int_to_env(const char *name, int value) { size_t len = 13 + strlen(name); char *buf = realloc(NULL, len); snprintf(buf, len, "%s=%d", name, value); putenv(buf); } static void s46_to_env_portparams(const uint8_t *data, size_t len, FILE *fp) { uint8_t *odata; uint16_t otype, olen; dhcpv6_for_each_option(data, &data[len], otype, olen, odata) { if (otype == DHCPV6_OPT_S46_PORTPARAMS && olen == sizeof(struct dhcpv6_s46_portparams)) { struct dhcpv6_s46_portparams *params = (void*)odata; fprintf(fp, "offset=%d,psidlen=%d,psid=%d,", params->offset, params->psid_len, ntohs(params->psid)); } } } static void s46_to_env(enum odhcp6c_state state, const uint8_t *data, size_t len) { const char *name = (state == STATE_S46_MAPE) ? "MAPE" : (state == STATE_S46_MAPT) ? "MAPT" : "LW4O6"; if (len == 0) return; char *str; size_t strsize; FILE *fp = open_memstream(&str, &strsize); fputs(name, fp); fputc('=', fp); const char *type = (state == STATE_S46_MAPE) ? "map-e" : (state == STATE_S46_MAPT) ? "map-t" : "lw4o6"; uint8_t *odata; uint16_t otype, olen; dhcpv6_for_each_option(data, &data[len], otype, olen, odata) { struct dhcpv6_s46_rule *rule = (struct dhcpv6_s46_rule*)odata; struct dhcpv6_s46_v4v6bind *bind = (struct dhcpv6_s46_v4v6bind*)odata; if (state != STATE_S46_LW && otype == DHCPV6_OPT_S46_RULE && olen >= sizeof(struct dhcpv6_s46_rule)) { char buf4[INET_ADDRSTRLEN]; char buf6[INET6_ADDRSTRLEN]; struct in6_addr in6 = IN6ADDR_ANY_INIT; size_t prefix6len = rule->prefix6_len; prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1; if (prefix6len > sizeof(in6) || olen < sizeof(struct dhcpv6_s46_rule) + prefix6len) continue; memcpy(&in6, rule->ipv6_prefix, prefix6len); inet_ntop(AF_INET, &rule->ipv4_prefix, buf4, sizeof(buf4)); inet_ntop(AF_INET6, &in6, buf6, sizeof(buf6)); if (rule->flags & 1) fputs("fmr,", fp); fprintf(fp, "type=%s,ealen=%d,prefix4len=%d,prefix6len=%d,ipv4prefix=%s,ipv6prefix=%s,", type, rule->ea_len, rule->prefix4_len, rule->prefix6_len, buf4, buf6); s46_to_env_portparams(&rule->ipv6_prefix[prefix6len], olen - sizeof(*rule) - prefix6len, fp); dhcpv6_for_each_option(data, &data[len], otype, olen, odata) { if (state != STATE_S46_MAPT && otype == DHCPV6_OPT_S46_BR && olen == sizeof(struct in6_addr)) { inet_ntop(AF_INET6, odata, buf6, sizeof(buf6)); fprintf(fp, "br=%s,", buf6); } else if (state == STATE_S46_MAPT && otype == DHCPV6_OPT_S46_DMR && olen >= sizeof(struct dhcpv6_s46_dmr)) { struct dhcpv6_s46_dmr *dmr = (struct dhcpv6_s46_dmr*)odata; memset(&in6, 0, sizeof(in6)); size_t prefix6len = dmr->dmr_prefix6_len; prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1; if (prefix6len > sizeof(in6) || olen < sizeof(struct dhcpv6_s46_dmr) + prefix6len) continue; memcpy(&in6, dmr->dmr_ipv6_prefix, prefix6len); inet_ntop(AF_INET6, &in6, buf6, sizeof(buf6)); fprintf(fp, "dmr=%s/%d,", buf6, dmr->dmr_prefix6_len); } } fputc(' ', fp); } else if (state == STATE_S46_LW && otype == DHCPV6_OPT_S46_V4V6BIND && olen >= sizeof(struct dhcpv6_s46_v4v6bind)) { char buf4[INET_ADDRSTRLEN]; char buf6[INET6_ADDRSTRLEN]; struct in6_addr in6 = IN6ADDR_ANY_INIT; size_t prefix6len = bind->bindprefix6_len; prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1; if (prefix6len > sizeof(in6) || olen < sizeof(struct dhcpv6_s46_v4v6bind) + prefix6len) continue; memcpy(&in6, bind->bind_ipv6_prefix, prefix6len); inet_ntop(AF_INET, &bind->ipv4_address, buf4, sizeof(buf4)); inet_ntop(AF_INET6, &in6, buf6, sizeof(buf6)); fprintf(fp, "type=%s,prefix4len=32,prefix6len=%d,ipv4prefix=%s,ipv6prefix=%s,", type, bind->bindprefix6_len, buf4, buf6); s46_to_env_portparams(&bind->bind_ipv6_prefix[prefix6len], olen - sizeof(*bind) - prefix6len, fp); dhcpv6_for_each_option(data, &data[len], otype, olen, odata) { if (otype == DHCPV6_OPT_S46_BR && olen == sizeof(struct in6_addr)) { inet_ntop(AF_INET6, odata, buf6, sizeof(buf6)); fprintf(fp, "br=%s,", buf6); } } fputc(' ', fp); } } fclose(fp); putenv(str); } void script_call(const char *status, int delay, bool resume) { time_t now = odhcp6c_get_milli_time() / 1000; bool running_script = false; if (running) { time_t diff = now - started; kill(running, SIGTERM); if (diff > delay) delay -= diff; else delay = 0; running_script = true; } if (resume || !running_script || !action[0]) strncpy(action, status, sizeof(action) - 1); pid_t pid = fork(); if (pid > 0) { running = pid; started = now; if (!resume) action[0] = 0; } else if (pid == 0) { size_t dns_len, search_len, custom_len, sntp_ip_len, ntp_ip_len, ntp_dns_len; size_t sip_ip_len, sip_fqdn_len, aftr_name_len, cer_len, addr_len; size_t s46_mapt_len, s46_mape_len, s46_lw_len, passthru_len; signal(SIGTERM, SIG_DFL); if (delay > 0) { sleep(delay); odhcp6c_expire(); } struct in6_addr *addr = odhcp6c_get_state(STATE_SERVER_ADDR, &addr_len); struct in6_addr *dns = odhcp6c_get_state(STATE_DNS, &dns_len); uint8_t *search = odhcp6c_get_state(STATE_SEARCH, &search_len); uint8_t *custom = odhcp6c_get_state(STATE_CUSTOM_OPTS, &custom_len); struct in6_addr *sntp = odhcp6c_get_state(STATE_SNTP_IP, &sntp_ip_len); struct in6_addr *ntp = odhcp6c_get_state(STATE_NTP_IP, &ntp_ip_len); uint8_t *ntp_dns = odhcp6c_get_state(STATE_NTP_FQDN, &ntp_dns_len); struct in6_addr *sip = odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len); uint8_t *sip_fqdn = odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len); uint8_t *aftr_name = odhcp6c_get_state(STATE_AFTR_NAME, &aftr_name_len); struct in6_addr *cer = odhcp6c_get_state(STATE_CER, &cer_len); uint8_t *s46_mapt = odhcp6c_get_state(STATE_S46_MAPT, &s46_mapt_len); uint8_t *s46_mape = odhcp6c_get_state(STATE_S46_MAPE, &s46_mape_len); uint8_t *s46_lw = odhcp6c_get_state(STATE_S46_LW, &s46_lw_len); uint8_t *passthru = odhcp6c_get_state(STATE_PASSTHRU, &passthru_len); size_t prefix_len, address_len, ra_pref_len, ra_route_len, ra_dns_len, ra_search_len; uint8_t *prefix = odhcp6c_get_state(STATE_IA_PD, &prefix_len); uint8_t *address = odhcp6c_get_state(STATE_IA_NA, &address_len); uint8_t *ra_pref = odhcp6c_get_state(STATE_RA_PREFIX, &ra_pref_len); uint8_t *ra_route = odhcp6c_get_state(STATE_RA_ROUTE, &ra_route_len); uint8_t *ra_dns = odhcp6c_get_state(STATE_RA_DNS, &ra_dns_len); uint8_t *ra_search = odhcp6c_get_state(STATE_RA_SEARCH, &ra_search_len); ipv6_to_env("SERVER", addr, addr_len / sizeof(*addr)); ipv6_to_env("RDNSS", dns, dns_len / sizeof(*dns)); ipv6_to_env("SNTP_IP", sntp, sntp_ip_len / sizeof(*sntp)); ipv6_to_env("NTP_IP", ntp, ntp_ip_len / sizeof(*ntp)); fqdn_to_env("NTP_FQDN", ntp_dns, ntp_dns_len); ipv6_to_env("SIP_IP", sip, sip_ip_len / sizeof(*sip)); fqdn_to_env("DOMAINS", search, search_len); fqdn_to_env("SIP_DOMAIN", sip_fqdn, sip_fqdn_len); fqdn_to_env("AFTR", aftr_name, aftr_name_len); ipv6_to_env("CER", cer, cer_len / sizeof(*cer)); s46_to_env(STATE_S46_MAPE, s46_mape, s46_mape_len); s46_to_env(STATE_S46_MAPT, s46_mapt, s46_mapt_len); s46_to_env(STATE_S46_LW, s46_lw, s46_lw_len); bin_to_env(custom, custom_len); if (odhcp6c_is_bound()) { entry_to_env("PREFIXES", prefix, prefix_len, ENTRY_PREFIX); entry_to_env("ADDRESSES", address, address_len, ENTRY_ADDRESS); } entry_to_env("RA_ADDRESSES", ra_pref, ra_pref_len, ENTRY_ADDRESS); entry_to_env("RA_ROUTES", ra_route, ra_route_len, ENTRY_ROUTE); entry_to_env("RA_DNS", ra_dns, ra_dns_len, ENTRY_HOST); search_to_env("RA_DOMAINS", ra_search, ra_search_len); int_to_env("RA_HOPLIMIT", ra_get_hoplimit()); int_to_env("RA_MTU", ra_get_mtu()); int_to_env("RA_REACHABLE", ra_get_reachable()); int_to_env("RA_RETRANSMIT", ra_get_retransmit()); char *buf = malloc(10 + passthru_len * 2); strncpy(buf, "PASSTHRU=", 10); script_hexlify(&buf[9], passthru, passthru_len); putenv(buf); execv(argv[0], argv); _exit(128); } }