#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
+#include <arpa/inet.h>
#include <netinet/in.h>
#include <net/if.h>
static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
- const uint8_t transaction[3], enum dhcpv6_msg type);
+ const uint8_t transaction[3], enum dhcpv6_msg type,
+ const struct in6_addr *daddr);
static int dhcpv6_parse_ia(void *opt, void *end);
const void *status_msg, const int len,
bool handled_status_codes[_DHCPV6_Status_Max],
int *ret);
+static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand);
+static void dhcpv6_clear_all_server_cand(void);
static reply_handler dhcpv6_handle_reply;
static reply_handler dhcpv6_handle_advert;
static int request_prefix = -1;
static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
static bool accept_reconfig = false;
+// Server unicast address
+static struct in6_addr server_addr = IN6ADDR_ANY_INIT;
// Reconfigure key
static uint8_t reconf_key[16];
-
int init_dhcpv6(const char *ifname, int request_pd, int sol_timeout)
{
request_prefix = request_pd;
dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+ if (sock < 0)
+ return -1;
// Detect interface
struct ifreq ifr;
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
- if (ioctl(sock, SIOCGIFINDEX, &ifr))
+ if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
return -1;
ifindex = ifr.ifr_ifindex;
size_t client_id_len;
odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
if (client_id_len == 0) {
- ioctl(sock, SIOCGIFHWADDR, &ifr);
uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
DHCPV6_DUID_LLADDR, 0, 1};
- memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
+
+ if (ioctl(sock, SIOCGIFHWADDR, &ifr) >= 0)
+ memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
struct ifreq ifs[100], *ifp, *ifend;
// If our interface doesn't have an address...
ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
for (ifp = ifc.ifc_req; ifp < ifend &&
- !memcmp(&duid[8], zero, 6); ifp++) {
+ !memcmp(&duid[8], zero, ETHER_ADDR_LEN); ifp++) {
memcpy(ifr.ifr_name, ifp->ifr_name,
sizeof(ifr.ifr_name));
- ioctl(sock, SIOCGIFHWADDR, &ifr);
+ if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0)
+ continue;
+
memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
ETHER_ADDR_LEN);
}
htons(DHCPV6_OPT_SIP_SERVER_A),
htons(DHCPV6_OPT_DNS_SERVERS),
htons(DHCPV6_OPT_DNS_DOMAIN),
+ htons(DHCPV6_OPT_UNICAST),
htons(DHCPV6_OPT_NTP_SERVER),
- htons(DHCPV6_OPT_SIP_SERVER_A),
htons(DHCPV6_OPT_AFTR_NAME),
htons(DHCPV6_OPT_PD_EXCLUDE),
#ifdef EXT_PREFIX_CLASS
};
odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
-
// Configure IPv6-options
int val = 1;
setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
+ setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val));
val = 0;
setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val));
setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
.sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
- if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)))
+ if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0)
return -1;
return 0;
0, ALL_DHCPV6_RELAYS, ifindex};
struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
- sendmsg(sock, &msg, 0);
+ switch (type) {
+ case DHCPV6_MSG_REQUEST:
+ case DHCPV6_MSG_RENEW:
+ case DHCPV6_MSG_RELEASE:
+ case DHCPV6_MSG_DECLINE:
+ if (!IN6_IS_ADDR_UNSPECIFIED(&server_addr) &&
+ odhcp6c_addr_in_scope(&server_addr)) {
+ srv.sin6_addr = server_addr;
+ if (!IN6_IS_ADDR_LINKLOCAL(&server_addr))
+ srv.sin6_scope_id = 0;
+ }
+ break;
+ default:
+ break;
+ }
+
+ if (sendmsg(sock, &msg, 0) < 0) {
+ char in6_str[INET6_ADDRSTRLEN];
+
+ syslog(LOG_ERR, "Failed to send DHCPV6 message to %s (%s)",
+ inet_ntop(AF_INET6, (const void *)&srv.sin6_addr,
+ in6_str, sizeof(in6_str)), strerror(errno));
+ }
}
int dhcpv6_request(enum dhcpv6_msg type)
{
- uint8_t buf[1536], rc = 0;
+ uint8_t rc = 0;
uint64_t timeout = UINT32_MAX;
struct dhcpv6_retx *retx = &dhcpv6_retx[type];
// Built and send package
if (type != DHCPV6_MSG_UNKNOWN) {
- syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)",
- retx->name, (unsigned long long)elapsed, rc);
+ if (type != DHCPV6_MSG_SOLICIT)
+ syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)",
+ retx->name, (unsigned long long)elapsed, rc);
dhcpv6_send(type, trid, elapsed / 10);
rc++;
}
// Receive rounds
- for (; len < 0 && round_start < round_end;
+ for (; len < 0 && (round_start < round_end);
round_start = odhcp6c_get_milli_time()) {
+ uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+ struct iovec iov = {buf, sizeof(buf)};
+ struct msghdr msg = {NULL, 0, &iov, 1,
+ cmsg_buf, sizeof(cmsg_buf), 0};
+ struct in6_pktinfo *pktinfo = NULL;
+
// Check for pending signal
if (odhcp6c_signal_process())
return -1;
&timeout, sizeof(timeout));
// Receive cycle
- len = recv(sock, buf, sizeof(buf), 0);
+ len = recvmsg(sock, &msg, 0);
+ if (len < 0)
+ continue;
+
+ for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
+ ch = CMSG_NXTHDR(&msg, ch)) {
+ if (ch->cmsg_level == SOL_IPV6 &&
+ ch->cmsg_type == IPV6_PKTINFO) {
+ pktinfo = (struct in6_pktinfo *)CMSG_DATA(ch);
+ break;
+ }
+ }
+
+ if (pktinfo == NULL) {
+ len = -1;
+ continue;
+ }
- if (!dhcpv6_response_is_valid(buf, len, trid, type))
+ if (!dhcpv6_response_is_valid(buf, len, trid,
+ type, &pktinfo->ipi6_addr)) {
len = -1;
+ continue;
+ }
- if (len > 0) {
- uint8_t *opt = &buf[4];
- uint8_t *opt_end = opt + len - 4;
+ uint8_t *opt = &buf[4];
+ uint8_t *opt_end = opt + len - 4;
- round_start = odhcp6c_get_milli_time();
- elapsed = round_start - start;
- syslog(LOG_NOTICE, "Got a valid reply after "
- "%llums", (unsigned long long)elapsed);
+ round_start = odhcp6c_get_milli_time();
+ elapsed = round_start - start;
+ syslog(LOG_NOTICE, "Got a valid reply after "
+ "%llums", (unsigned long long)elapsed);
- if (retx->handler_reply)
- len = retx->handler_reply(
- type, rc, opt, opt_end);
+ if (retx->handler_reply)
+ len = retx->handler_reply(type, rc, opt, opt_end);
- if (len > 0 && round_end - round_start > 1000)
- round_end = 1000 + round_start;
- }
+ if (len > 0 && round_end - round_start > 1000)
+ round_end = 1000 + round_start;
}
// Allow
return len;
}
-
+// Message validation checks according to RFC3315 chapter 15
static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
- const uint8_t transaction[3], enum dhcpv6_msg type)
+ const uint8_t transaction[3], enum dhcpv6_msg type,
+ const struct in6_addr *daddr)
{
const struct dhcpv6_header *rep = buf;
if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
return false;
}
- uint8_t *end = ((uint8_t*)buf) + len, *odata;
+ uint8_t *end = ((uint8_t*)buf) + len, *odata,
+ rcmsg = DHCPV6_MSG_UNKNOWN;
uint16_t otype, olen;
- bool clientid_ok = false, serverid_ok = false, rcauth_ok = false;
+ bool clientid_ok = false, serverid_ok = false, rcauth_ok = false,
+ ia_present = false, options_valid = true;
size_t client_id_len, server_id_len;
void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
clientid_ok = (olen + 4U == client_id_len) && !memcmp(
&odata[-4], client_id, client_id_len);
} else if (otype == DHCPV6_OPT_SERVERID) {
- serverid_ok = (olen + 4U == server_id_len) && !memcmp(
- &odata[-4], server_id, server_id_len);
+ if (server_id_len)
+ serverid_ok = (olen + 4U == server_id_len) && !memcmp(
+ &odata[-4], server_id, server_id_len);
+ else
+ serverid_ok = true;
} else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
sizeof(struct dhcpv6_auth_reconfigure)) {
struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
md5_finish(&md5, hash);
rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
+ } else if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1) {
+ rcmsg = odata[0];
+ } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) {
+ ia_present = true;
+ if (olen < sizeof(struct dhcpv6_ia_hdr))
+ options_valid = false;
+ }
+ else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) ||
+ (otype == DHCPV6_OPT_PD_EXCLUDE)) {
+ // Options are not allowed on global level
+ options_valid = false;
}
}
- if (rep->msg_type == DHCPV6_MSG_RECONF && !rcauth_ok)
+ if (!options_valid)
return false;
- return clientid_ok && (serverid_ok || server_id_len == 0);
+ if (type == DHCPV6_MSG_INFO_REQ && ia_present)
+ return false;
+
+ if (rep->msg_type == DHCPV6_MSG_RECONF) {
+ if ((rcmsg != DHCPV6_MSG_RENEW && rcmsg != DHCPV6_MSG_INFO_REQ) ||
+ (rcmsg == DHCPV6_MSG_INFO_REQ && ia_present) ||
+ !rcauth_ok || IN6_IS_ADDR_MULTICAST(daddr))
+ return false;
+ }
+
+ return clientid_ok && serverid_ok;
}
static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc,
const void *opt, const void *end)
{
- // TODO: should verify the reconfigure message
uint16_t otype, olen;
uint8_t *odata, msg = DHCPV6_MSG_RENEW;
dhcpv6_for_each_option(opt, end, otype, olen, odata)
{
uint16_t olen, otype;
uint8_t *odata, pref = 0;
- struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, NULL, NULL, 0, 0};
+ struct dhcpv6_server_cand cand = {false, false, 0, 0, {0},
+ IN6ADDR_ANY_INIT, NULL, NULL, 0, 0};
bool have_na = false;
int have_pd = 0;
} else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
cand.preference >= 0) {
cand.preference = pref = odata[0];
+ } else if (otype == DHCPV6_OPT_UNICAST && olen == sizeof(cand.server_addr)) {
+ cand.server_addr = *(struct in6_addr *)odata;
} else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
cand.wants_reconfigure = true;
} else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
if (cand.duid_len > 0) {
cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
- odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
- }
-
- if (orig == DHCPV6_MSG_SOLICIT) {
- odhcp6c_clear_state(STATE_IA_NA);
- odhcp6c_clear_state(STATE_IA_PD);
+ dhcpv6_add_server_cand(&cand);
}
return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
static int dhcpv6_commit_advert(void)
{
- size_t cand_len;
- struct dhcpv6_server_cand *c = NULL, *cand =
- odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
-
- bool retry = false;
- for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
- if (cand[i].has_noaddravail)
- retry = true; // We want to try again
-
- if (!c || c->preference < cand[i].preference)
- c = &cand[i];
- }
-
- if (retry && na_mode == IA_MODE_TRY) {
- // We give it a second try without the IA_NA
- na_mode = IA_MODE_NONE;
- return dhcpv6_request(DHCPV6_MSG_SOLICIT);
- }
-
- if (c) {
- uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID),
- htons(c->duid_len)};
- odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
- odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
- accept_reconfig = c->wants_reconfigure;
- if (c->ia_na_len)
- odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
- if (c->ia_pd_len)
- odhcp6c_add_state(STATE_IA_PD, c->ia_pd, c->ia_pd_len);
- }
-
- for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
- free(cand[i].ia_na);
- free(cand[i].ia_pd);
- }
- odhcp6c_clear_state(STATE_SERVER_CAND);
-
- if (!c)
- return -1;
- else if ((request_prefix && c->ia_pd_len) || (na_mode != IA_MODE_NONE && c->ia_na_len))
- return DHCPV6_STATEFUL;
- else
- return DHCPV6_STATELESS;
+ return dhcpv6_promote_server_cand();
}
const void *opt, const void *end)
{
dhcpv6_handle_advert(orig, rc, opt, end);
- if (dhcpv6_commit_advert() < 0) {
- dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
+ if (dhcpv6_commit_advert() < 0)
return -1;
- }
return dhcpv6_handle_reply(orig, rc, opt, end);
}
continue;
dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
+ } else if (otype == DHCPV6_OPT_UNICAST && olen == sizeof(server_addr)) {
+ server_addr = *(struct in6_addr *)odata;
} else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
uint8_t *mdata = (olen > 2) ? &odata[2] : NULL;
uint16_t mlen = (olen > 2) ? olen - 2 : 0;
ret = -1;
break;
+ case DHCPV6_MSG_REQUEST:
+ // All server candidates can be cleared if not yet bound
+ if (!odhcp6c_is_bound())
+ dhcpv6_clear_all_server_cand();
+
default :
break;
}
}
}
- else if (ret > 0)
+ else if (ret > 0) {
+ // All server candidates can be cleared if not yet bound
+ if (!odhcp6c_is_bound())
+ dhcpv6_clear_all_server_cand();
+
t1 = refresh;
+ }
return ret;
}
break;
case DHCPV6_UseMulticast:
- // TODO handle multicast status code
+ switch(orig) {
+ case DHCPV6_MSG_REQUEST:
+ case DHCPV6_MSG_RENEW:
+ case DHCPV6_MSG_RELEASE:
+ case DHCPV6_MSG_DECLINE:
+ // Message needs to be retransmitted according to RFC3315 chapter 18.1.8
+ server_addr = in6addr_any;
+ *ret = 0;
+ break;
+ default:
+ break;
+ }
break;
case DHCPV6_NoAddrsAvail:
break;
}
}
+
+static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand)
+{
+ size_t cand_len, i;
+ struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
+
+ // Remove identical duid server candidate
+ for (i = 0; i < cand_len / sizeof(*c); ++i) {
+ if (cand->duid_len == c[i].duid_len &&
+ !memcmp(cand->duid, c[i].duid, cand->duid_len)) {
+ free(c[i].ia_na);
+ free(c[i].ia_pd);
+ odhcp6c_remove_state(STATE_SERVER_CAND, i * sizeof(*c), sizeof(*c));
+ break;
+ }
+ }
+
+ for (i = 0, c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
+ i < cand_len / sizeof(*c); ++i) {
+ if (c[i].preference < cand->preference)
+ break;
+ }
+
+ odhcp6c_insert_state(STATE_SERVER_CAND, i * sizeof(*c), cand, sizeof(*cand));
+}
+
+static void dhcpv6_clear_all_server_cand(void)
+{
+ size_t cand_len, i;
+ struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
+
+ // Server candidates need deep delete for IA_NA/IA_PD
+ for (i = 0; i < cand_len / sizeof(*c); ++i) {
+ if (c[i].ia_na)
+ free(c[i].ia_na);
+ if (c[i].ia_pd)
+ free(c[i].ia_pd);
+ }
+ odhcp6c_clear_state(STATE_SERVER_CAND);
+}
+
+int dhcpv6_promote_server_cand(void)
+{
+ size_t cand_len;
+ struct dhcpv6_server_cand *cand = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
+ uint16_t hdr[2];
+ int ret = DHCPV6_STATELESS;
+
+ // Clear lingering candidate state info
+ odhcp6c_clear_state(STATE_SERVER_ID);
+ odhcp6c_clear_state(STATE_IA_NA);
+ odhcp6c_clear_state(STATE_IA_PD);
+
+ if (!cand_len)
+ return -1;
+
+ if (cand->has_noaddravail && na_mode == IA_MODE_TRY) {
+ na_mode = IA_MODE_NONE;
+ return dhcpv6_request(DHCPV6_MSG_SOLICIT);
+ }
+
+ hdr[0] = htons(DHCPV6_OPT_SERVERID);
+ hdr[1] = htons(cand->duid_len);
+ odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
+ odhcp6c_add_state(STATE_SERVER_ID, cand->duid, cand->duid_len);
+ accept_reconfig = cand->wants_reconfigure;
+ if (cand->ia_na_len) {
+ odhcp6c_add_state(STATE_IA_NA, cand->ia_na, cand->ia_na_len);
+ free(cand->ia_na);
+ if (na_mode != IA_MODE_NONE)
+ ret = DHCPV6_STATEFUL;
+ }
+ if (cand->ia_pd_len) {
+ odhcp6c_add_state(STATE_IA_PD, cand->ia_pd, cand->ia_pd_len);
+ free(cand->ia_pd);
+ if (request_prefix)
+ ret = DHCPV6_STATEFUL;
+ }
+
+ odhcp6c_remove_state(STATE_SERVER_CAND, 0, sizeof(*cand));
+
+ return ret;
+}
projects / odhcp6c.git / blobdiff