only. Default: disabled.
<tag>password <m/string/</tag>
- Use this password for MD5 authentication of BGP sessions. Default: no
- authentication. Password has to be set by external utility
- (e.g. setkey(8)) on BSD systems.
+ Use this password for MD5 authentication of BGP sessions (RFC 2385).
+ When used on BSD systems, see also <cf/setkey/ option below. Default:
+ no authentication.
+
+ <tag>setkey <m/switch/</tag>
+ On BSD systems, keys for TCP MD5 authentication are stored in the global
+ SA/SP database, which can be accessed by external utilities (e.g.
+ setkey(8)). BIRD configures security associations in the SA/SP database
+ automatically based on <cf/password/ options (see above), this option
+ allows to disable automatic updates by BIRD when manual configuration by
+ external utilities is preferred. Note that automatic SA/SP database
+ updates are currently implemented only for FreeBSD. Passwords have to be
+ set manually by an external utility on NetBSD and OpenBSD. Default:
+ enabled (ignored on non-FreeBSD).
<tag>passive <m/switch/</tag>
Standard BGP behavior is both initiating outgoing connections and
int sk_setup_broadcast(sock *s);
int sk_set_ttl(sock *s, int ttl); /* Set transmit TTL for given socket */
int sk_set_min_ttl(sock *s, int ttl); /* Set minimal accepted TTL for given socket */
-int sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd);
+int sk_set_md5_auth(sock *s, ip_addr local, ip_addr remote, struct iface *ifa, char *passwd, int setkey);
int sk_set_ipv6_checksum(sock *s, int offset);
int sk_set_icmp6_filter(sock *s, int p1, int p2);
void sk_log_error(sock *s, const char *p);
bgp_counter++;
if (p->cf->password)
- if (sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, p->cf->password) < 0)
+ if (sk_set_md5_auth(bgp_listen_sk, p->cf->source_addr, p->cf->remote_ip,
+ p->cf->iface, p->cf->password, p->cf->setkey) < 0)
{
sk_log_error(bgp_listen_sk, p->p.name);
bgp_close(p, 0);
bgp_counter--;
if (p->cf->password && apply_md5)
- if (sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, NULL) < 0)
+ if (sk_set_md5_auth(bgp_listen_sk, p->cf->source_addr, p->cf->remote_ip,
+ p->cf->iface, NULL, p->cf->setkey) < 0)
sk_log_error(bgp_listen_sk, p->p.name);
if (!bgp_counter)
int add_path; /* Use ADD-PATH extension [draft] */
int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */
int gr_mode; /* Graceful restart mode (BGP_GR_*) */
+ int setkey; /* Set MD5 password to system SA/SP database */
unsigned gr_time; /* Graceful restart timeout */
unsigned connect_delay_time; /* Minimum delay between connect attempts */
unsigned connect_retry_time; /* Timeout for connect attempts */
INTERPRET, COMMUNITIES, BGP_ORIGINATOR_ID, BGP_CLUSTER_LIST, IGP,
TABLE, GATEWAY, DIRECT, RECURSIVE, MED, TTL, SECURITY, DETERMINISTIC,
SECONDARY, ALLOW, BFD, ADD, PATHS, RX, TX, GRACEFUL, RESTART, AWARE,
- CHECK, LINK, PORT, EXTENDED, MESSAGES)
+ CHECK, LINK, PORT, EXTENDED, MESSAGES, SETKEY)
CF_GRAMMAR
BGP_CFG->default_local_pref = 100;
BGP_CFG->gr_mode = BGP_GR_AWARE;
BGP_CFG->gr_time = 120;
+ BGP_CFG->setkey = 1;
}
;
| bgp_proto CAPABILITIES bool ';' { BGP_CFG->capabilities = $3; }
| bgp_proto ADVERTISE IPV4 bool ';' { BGP_CFG->advertise_ipv4 = $4; }
| bgp_proto PASSWORD text ';' { BGP_CFG->password = $3; }
+ | bgp_proto SETKEY bool ';' { BGP_CFG->setkey = $3; }
| bgp_proto ROUTE LIMIT expr ';' {
this_proto->in_limit = cfg_allocz(sizeof(struct proto_limit));
this_proto->in_limit->limit = $4;
krt-sock.Y
krt-sys.h
sysio.h
+setkey.h
--- /dev/null
+/*
+ * BIRD -- Manipulation the IPsec SA/SP database using setkey(8) utility
+ *
+ * (c) 2016 CZ.NIC z.s.p.o.
+ */
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <net/pfkeyv2.h>
+#include <netipsec/ipsec.h>
+
+#include "nest/bird.h"
+#include "lib/unix.h"
+
+
+/*
+ * Open a socket for manage the IPsec SA/SP database entries
+ */
+static int
+setkey_open_socket(void)
+{
+ int s = socket(PF_KEY, SOCK_RAW, PF_KEY_V2);
+ if (s < 0)
+ {
+ log(L_ERR "SETKEY: socket: %m");
+ return -1;
+ }
+
+ return s;
+}
+
+static int
+setkey_send(struct sadb_msg *msg, uint len)
+{
+ int s = setkey_open_socket();
+ if (s < 0)
+ return -1;
+
+ if (msg->sadb_msg_type == SADB_ADD)
+ {
+ /* Delete possible current key in the IPsec SA/SP database */
+ msg->sadb_msg_type = SADB_DELETE;
+ send(s, msg, len, 0);
+ msg->sadb_msg_type = SADB_ADD;
+ }
+
+ if (send(s, msg, len, 0) < 0)
+ {
+ log(L_ERR "SETKEY: send: %m");
+ close(s);
+ return -1;
+ }
+
+ close(s);
+ return 0;
+}
+
+/*
+ * Perform setkey(8)-like operation for set the password for TCP MD5 Signature.
+ * Could be called with SABD_ADD or SADB_DELETE argument. Note that SADB_ADD
+ * argument is internally processed as a pair of SADB_ADD and SADB_DELETE
+ * operations to implement replace.
+ */
+static int
+setkey_md5(sockaddr *src, sockaddr *dst, char *passwd, uint type)
+{
+ uint passwd_len = passwd ? strlen(passwd) : 0;
+
+ uint total =
+ sizeof(struct sadb_msg) +
+ sizeof(struct sadb_key) + PFKEY_ALIGN8(passwd_len) +
+ sizeof(struct sadb_sa) +
+ sizeof(struct sadb_x_sa2) +
+ sizeof(struct sadb_address) + PFKEY_ALIGN8(src->sa.sa_len) +
+ sizeof(struct sadb_address) + PFKEY_ALIGN8(dst->sa.sa_len);
+
+ char *buf = alloca(total);
+ char *pos = buf;
+ uint len;
+
+ memset(buf, 0, total);
+
+ struct sadb_msg *msg = (void *) pos;
+ len = sizeof(struct sadb_msg);
+ msg->sadb_msg_version = PF_KEY_V2;
+ msg->sadb_msg_type = type;
+ msg->sadb_msg_satype = SADB_X_SATYPE_TCPSIGNATURE;
+ msg->sadb_msg_len = 0; /* Fix it later */
+ msg->sadb_msg_pid = getpid();
+ pos += len;
+
+ /* Set authentication algorithm and password */
+ struct sadb_key *key = (void *) pos;
+ len = sizeof(struct sadb_key) + PFKEY_ALIGN8(passwd_len);
+ key->sadb_key_len = PFKEY_UNIT64(len);
+ key->sadb_key_exttype = SADB_EXT_KEY_AUTH;
+ key->sadb_key_bits = passwd_len * 8;
+ memcpy(pos + sizeof(struct sadb_key), passwd, passwd_len);
+ pos += len;
+
+ struct sadb_sa *sa = (void *) pos;
+ len = sizeof(struct sadb_sa);
+ sa->sadb_sa_len = PFKEY_UNIT64(len);
+ sa->sadb_sa_exttype = SADB_EXT_SA;
+ sa->sadb_sa_spi = htonl((u32) TCP_SIG_SPI);
+ sa->sadb_sa_auth = SADB_X_AALG_TCP_MD5;
+ sa->sadb_sa_encrypt = SADB_EALG_NONE;
+ sa->sadb_sa_flags = SADB_X_EXT_CYCSEQ;
+ pos += len;
+
+ struct sadb_x_sa2 *sa2 = (void *) pos;
+ len = sizeof(struct sadb_x_sa2);
+ sa2->sadb_x_sa2_len = PFKEY_UNIT64(len);
+ sa2->sadb_x_sa2_exttype = SADB_X_EXT_SA2;
+ sa2->sadb_x_sa2_mode = IPSEC_MODE_ANY;
+ pos += len;
+
+ /* Set source address */
+ struct sadb_address *saddr = (void *) pos;
+ len = sizeof(struct sadb_address) + PFKEY_ALIGN8(src->sa.sa_len);
+ saddr->sadb_address_len = PFKEY_UNIT64(len);
+ saddr->sadb_address_exttype = SADB_EXT_ADDRESS_SRC;
+ saddr->sadb_address_proto = IPSEC_ULPROTO_ANY;
+ saddr->sadb_address_prefixlen = MAX_PREFIX_LENGTH;
+ memcpy(pos + sizeof(struct sadb_address), &src->sa, src->sa.sa_len);
+ pos += len;
+
+ /* Set destination address */
+ struct sadb_address *daddr = (void *) pos;
+ len = sizeof(struct sadb_address) + PFKEY_ALIGN8(dst->sa.sa_len);
+ daddr->sadb_address_len = PFKEY_UNIT64(len);
+ daddr->sadb_address_exttype = SADB_EXT_ADDRESS_DST;
+ daddr->sadb_address_proto = IPSEC_ULPROTO_ANY;
+ daddr->sadb_address_prefixlen = MAX_PREFIX_LENGTH;
+ memcpy(pos + sizeof(struct sadb_address), &dst->sa, dst->sa.sa_len);
+ pos += len;
+
+ len = pos - buf;
+ msg->sadb_msg_len = PFKEY_UNIT64(len);
+
+ return setkey_send(msg, len);
+}
+
+/*
+ * Manipulation with the IPsec SA/SP database
+ */
+static int
+sk_set_md5_in_sasp_db(sock *s, ip_addr local, ip_addr remote, struct iface *ifa, char *passwd)
+{
+ sockaddr src, dst;
+ sockaddr_fill(&src, s->af, local, ifa, 0);
+ sockaddr_fill(&dst, s->af, remote, ifa, 0);
+
+ if (passwd && *passwd)
+ {
+ int len = strlen(passwd);
+ if (len > TCP_KEYLEN_MAX)
+ ERR_MSG("The password for TCP MD5 Signature is too long");
+
+ if (setkey_md5(&src, &dst, passwd, SADB_ADD) < 0)
+ ERR_MSG("Cannot add TCP-MD5 password into the IPsec SA/SP database");
+ }
+ else
+ {
+ if (setkey_md5(&src, &dst, NULL, SADB_DELETE) < 0)
+ ERR_MSG("Cannot delete TCP-MD5 password from the IPsec SA/SP database");
+ }
+ return 0;
+}
#ifndef TCP_KEYLEN_MAX
#define TCP_KEYLEN_MAX 80
#endif
+
#ifndef TCP_SIG_SPI
#define TCP_SIG_SPI 0x1000
#endif
-/*
- * FIXME: Passwords has to be set by setkey(8) command. This is the same
- * behaviour like Quagga. We need to add code for SA/SP entries
- * management.
- */
+#if defined(__FreeBSD__)
+#define USE_MD5SIG_SETKEY
+#include "lib/setkey.h"
+#endif
int
-sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
+sk_set_md5_auth(sock *s, ip_addr local, ip_addr remote, struct iface *ifa, char *passwd, int setkey UNUSED)
{
- int enable = 0;
-
- if (passwd && *passwd)
- {
- int len = strlen(passwd);
- enable = TCP_SIG_SPI;
-
- if (len > TCP_KEYLEN_MAX)
- ERR_MSG("MD5 password too long");
- }
+#ifdef USE_MD5SIG_SETKEY
+ if (setkey)
+ if (sk_set_md5_in_sasp_db(s, local, remote, ifa, passwd) < 0)
+ return -1;
+#endif
+ int enable = (passwd && *passwd) ? TCP_SIG_SPI : 0;
if (setsockopt(s->fd, IPPROTO_TCP, TCP_MD5SIG, &enable, sizeof(enable)) < 0)
{
if (errno == ENOPROTOOPT)
*/
int
-sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
+sk_set_md5_auth(sock *s, ip_addr local UNUSED, ip_addr remote, struct iface *ifa, char *passwd, int setkey UNUSED)
{
struct tcp_md5sig md5;
memset(&md5, 0, sizeof(md5));
- sockaddr_fill((sockaddr *) &md5.tcpm_addr, s->af, a, ifa, 0);
+ sockaddr_fill((sockaddr *) &md5.tcpm_addr, s->af, remote, ifa, 0);
if (passwd)
{
int len = strlen(passwd);
if (len > TCP_MD5SIG_MAXKEYLEN)
- ERR_MSG("MD5 password too long");
+ ERR_MSG("The password for TCP MD5 Signature is too long");
md5.tcpm_keylen = len;
memcpy(&md5.tcpm_key, passwd, len);
/**
* sk_set_md5_auth - add / remove MD5 security association for given socket
* @s: socket
- * @a: IP address of the other side
+ * @local: IP address of local side
+ * @remote: IP address of remote side
* @ifa: Interface for link-local IP address
- * @passwd: password used for MD5 authentication
+ * @passwd: Password used for MD5 authentication
+ * @setkey: Update also system SA/SP database
*
- * In TCP MD5 handling code in kernel, there is a set of pairs (address,
- * password) used to choose password according to address of the other side.
- * This function is useful for listening socket, for active sockets it is enough
- * to set s->password field.
+ * In TCP MD5 handling code in kernel, there is a set of security associations
+ * used for choosing password and other authentication parameters according to
+ * the local and remote address. This function is useful for listening socket,
+ * for active sockets it may be enough to set s->password field.
*
* When called with passwd != NULL, the new pair is added,
* When called with passwd == NULL, the existing pair is removed.
*
+ * Note that while in Linux, the MD5 SAs are specific to socket, in BSD they are
+ * stored in global SA/SP database (but the behavior also must be enabled on
+ * per-socket basis). In case of multiple sockets to the same neighbor, the
+ * socket-specific state must be configured for each socket while global state
+ * just once per src-dst pair. The @setkey argument controls whether the global
+ * state (SA/SP database) is also updated.
+ *
* Result: 0 for success, -1 for an error.
*/
int
-sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
+sk_set_md5_auth(sock *s, ip_addr local, ip_addr remote, struct iface *ifa, char *passwd, int setkey)
{ DUMMY; }
#endif
}
if (s->password)
- if (sk_set_md5_auth(s, s->daddr, s->iface, s->password) < 0)
+ if (sk_set_md5_auth(s, s->saddr, s->daddr, s->iface, s->password, 0) < 0)
goto err;
switch (s->type)