OSPF: Support of authentication trailer for OSPFv3
Implement RFC 7166, crypthographic authentication for OSPFv3 analogous to authentication used for OSPFv2.
This commit is contained in:
Ondrej Zajicek (work)
parent
f3a8cf050e
commit
4727d1db9d
7 changed files with 265 additions and 46 deletions
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@ -37,7 +37,7 @@ ospf_iface_finish(void)
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ip->passwords = get_passwords();
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if ((ip->autype == OSPF_AUTH_CRYPT) && (ip->helloint < 5))
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if (ospf_cfg_is_v2() && (ip->autype == OSPF_AUTH_CRYPT) && (ip->helloint < 5))
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log(L_WARN "Hello or poll interval less that 5 makes cryptographic authenication prone to replay attacks");
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if ((ip->autype == OSPF_AUTH_NONE) && (ip->passwords != NULL))
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@ -54,6 +54,9 @@ ospf_iface_finish(void)
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/* Set default OSPF crypto algorithms */
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if (!pass->alg && (ip->autype == OSPF_AUTH_CRYPT))
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pass->alg = ospf_cfg_is_v2() ? ALG_MD5 : ALG_HMAC_SHA256;
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if (ospf_cfg_is_v3() && ip->autype && (pass->alg < ALG_HMAC))
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cf_error("Keyed hash algorithms are not allowed, use HMAC algorithms");
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}
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}
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}
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@ -181,7 +184,7 @@ static inline void
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ospf_check_auth(void)
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{
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if (ospf_cfg_is_v3())
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cf_error("Authentication not supported in OSPFv3");
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cf_error("Plaintext authentication not supported in OSPFv3");
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}
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@ -346,8 +349,8 @@ ospf_vlink_item:
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| DEAD COUNT expr { OSPF_PATT->deadc = $3 ; if ($3<=1) cf_error("Dead count must be greater than one"); }
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| AUTHENTICATION NONE { OSPF_PATT->autype = OSPF_AUTH_NONE; }
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| AUTHENTICATION SIMPLE { OSPF_PATT->autype = OSPF_AUTH_SIMPLE; ospf_check_auth(); }
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| AUTHENTICATION CRYPTOGRAPHIC { OSPF_PATT->autype = OSPF_AUTH_CRYPT; ospf_check_auth(); }
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| password_list { ospf_check_auth(); }
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| AUTHENTICATION CRYPTOGRAPHIC { OSPF_PATT->autype = OSPF_AUTH_CRYPT; }
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| password_list
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;
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ospf_vlink_start: VIRTUAL LINK idval
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@ -396,7 +399,7 @@ ospf_iface_item:
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| NEIGHBORS '{' nbma_list '}'
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| AUTHENTICATION NONE { OSPF_PATT->autype = OSPF_AUTH_NONE; }
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| AUTHENTICATION SIMPLE { OSPF_PATT->autype = OSPF_AUTH_SIMPLE; ospf_check_auth(); }
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| AUTHENTICATION CRYPTOGRAPHIC { OSPF_PATT->autype = OSPF_AUTH_CRYPT; ospf_check_auth(); }
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| AUTHENTICATION CRYPTOGRAPHIC { OSPF_PATT->autype = OSPF_AUTH_CRYPT; }
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| RX BUFFER NORMAL { OSPF_PATT->rx_buffer = 0; }
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| RX BUFFER LARGE { OSPF_PATT->rx_buffer = OSPF_MAX_PKT_SIZE; }
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| RX BUFFER expr { OSPF_PATT->rx_buffer = $3; if (($3 < OSPF_MIN_PKT_SIZE) || ($3 > OSPF_MAX_PKT_SIZE)) cf_error("Buffer size must be in range 256-65535"); }
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@ -406,7 +409,7 @@ ospf_iface_item:
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| TTL SECURITY bool { OSPF_PATT->ttl_security = $3; }
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| TTL SECURITY TX ONLY { OSPF_PATT->ttl_security = 2; }
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| BFD bool { OSPF_PATT->bfd = $2; cf_check_bfd($2); }
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| password_list { ospf_check_auth(); }
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| password_list
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;
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pref_list:
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@ -14,7 +14,7 @@
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struct ospf_dbdes2_packet
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{
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struct ospf_packet hdr;
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union ospf_auth auth;
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union ospf_auth2 auth;
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u16 iface_mtu;
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u8 options;
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@ -38,6 +38,13 @@ struct ospf_dbdes3_packet
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};
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uint
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ospf_dbdes3_options(struct ospf_packet *pkt)
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{
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struct ospf_dbdes3_packet *ps = (void *) pkt;
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return ntohl(ps->options);
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}
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static inline uint
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ospf_dbdes_hdrlen(struct ospf_proto *p)
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{
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@ -45,7 +52,6 @@ ospf_dbdes_hdrlen(struct ospf_proto *p)
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sizeof(struct ospf_dbdes2_packet) : sizeof(struct ospf_dbdes3_packet);
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}
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static void
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ospf_dbdes_body(struct ospf_proto *p, struct ospf_packet *pkt,
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struct ospf_lsa_header **body, uint *count)
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@ -129,7 +135,7 @@ ospf_prepare_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
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else /* OSPFv3 */
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{
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struct ospf_dbdes3_packet *ps = (void *) pkt;
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ps->options = htonl(ifa->oa->options);
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ps->options = htonl(ifa->oa->options | (ifa->autype == OSPF_AUTH_CRYPT ? OPT_AT : 0));
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ps->iface_mtu = htons(iface_mtu);
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ps->padding = 0;
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ps->imms = 0; /* Will be set later */
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@ -14,7 +14,7 @@
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struct ospf_hello2_packet
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{
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struct ospf_packet hdr;
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union ospf_auth auth;
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union ospf_auth2 auth;
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u32 netmask;
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u16 helloint;
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@ -42,6 +42,13 @@ struct ospf_hello3_packet
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};
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uint
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ospf_hello3_options(struct ospf_packet *pkt)
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{
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struct ospf_hello3_packet *ps = (void *) pkt;
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return ntohl(ps->options) & 0x00FFFFFF;
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}
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void
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ospf_send_hello(struct ospf_iface *ifa, int kind, struct ospf_neighbor *dirn)
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{
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@ -86,9 +93,10 @@ ospf_send_hello(struct ospf_iface *ifa, int kind, struct ospf_neighbor *dirn)
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else
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{
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struct ospf_hello3_packet *ps = (void *) pkt;
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u32 options = ifa->oa->options | (ifa->autype == OSPF_AUTH_CRYPT ? OPT_AT : 0);
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ps->iface_id = htonl(ifa->iface_id);
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ps->options = ntohl(ifa->oa->options | (ifa->priority << 24));
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ps->options = ntohl(options | (ifa->priority << 24));
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ps->helloint = ntohs(ifa->helloint);
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ps->deadint = htons(ifa->deadint);
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ps->dr = htonl(ifa->drid);
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@ -334,7 +342,6 @@ ospf_receive_hello(struct ospf_packet *pkt, struct ospf_iface *ifa,
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n->priority = rcv_priority;
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n->iface_id = rcv_iface_id;
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/* Update inactivity timer */
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ospf_neigh_sm(n, INM_HELLOREC);
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@ -61,7 +61,10 @@ ifa_tx_hdrlen(struct ospf_iface *ifa)
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/* Relevant just for OSPFv2 */
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if (ifa->autype == OSPF_AUTH_CRYPT)
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{
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hlen += ospf_is_v2(p) ? 0 : sizeof(struct ospf_auth3);
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hlen += max_mac_length(ifa->passwords);
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}
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return hlen;
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}
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@ -137,7 +140,7 @@ ospf_sk_open(struct ospf_iface *ifa)
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goto err;
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/* 12 is an offset of the checksum in an OSPFv3 packet */
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if (ospf_is_v3(p))
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if (ospf_is_v3(p) && !ifa->autype)
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if (sk_set_ipv6_checksum(sk, 12) < 0)
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goto err;
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@ -828,6 +831,14 @@ ospf_iface_reconfigure(struct ospf_iface *ifa, struct ospf_iface_patt *new)
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{
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OSPF_TRACE(D_EVENTS, "Changing authentication type of %s", ifname);
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ifa->autype = new->autype;
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/* For OSPFv3, we need to update checksum calculation by OS */
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if (ospf_is_v3(p) && ifa->sk)
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if (sk_set_ipv6_checksum(ifa->sk, ifa->autype ? -1 : 12) < 0)
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{
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sk_log_error(ifa->sk, p->p.name);
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return 0;
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}
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}
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/* Update passwords */
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@ -84,8 +84,6 @@ ospf_neighbor_new(struct ospf_iface *ifa)
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n->pool = pool;
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n->ifa = ifa;
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add_tail(&ifa->neigh_list, NODE n);
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n->adj = 0;
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n->csn = 0;
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n->state = NEIGHBOR_DOWN;
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init_lists(p, n);
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@ -69,6 +69,9 @@
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#define MINLSARRIVAL (1 S_)
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#define LSINFINITY 0xffffff
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#define OSPF_PKT_TYPES 5 /* HELLO_P .. LSACK_P */
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#define OSPF3_CRYPTO_ID 1 /* OSPFv3 Cryptographic Protocol ID */
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#define OSPF_DEFAULT_TICK 1
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#define OSPF_DEFAULT_STUB_COST 1000
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#define OSPF_DEFAULT_ECMP_LIMIT 16
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@ -222,6 +225,7 @@ struct ospf_proto
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u8 merge_external; /* Should i merge external routes? */
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u8 asbr; /* May i originate any ext/NSSA lsa? */
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u8 ecmp; /* Maximal number of nexthops in ECMP route, or 0 */
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u64 csn64; /* Last used cryptographic sequence number */
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struct ospf_area *backbone; /* If exists */
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event *flood_event; /* Event for flooding LS updates */
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void *lsab; /* LSA buffer used when originating router LSAs */
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@ -254,8 +258,6 @@ struct ospf_area
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struct fib rtr; /* Routing tables for routers */
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};
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struct ospf_iface
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{
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node n;
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@ -387,7 +389,8 @@ struct ospf_neighbor
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struct bfd_request *bfd_req; /* BFD request, if BFD is used */
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void *ldd_buffer; /* Last database description packet */
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u32 ldd_bsize; /* Buffer size for ldd_buffer */
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u32 csn; /* Last received crypt seq number (for MD5) */
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u32 csn; /* OSPFv2: Last received crypt seq number */
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u64 csn64[OSPF_PKT_TYPES]; /* OSPFv3: Last received CSN for each type of packet */
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};
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@ -422,6 +425,7 @@ struct ospf_neighbor
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#define OSPF_AUTH_SIMPLE 1
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#define OSPF_AUTH_CRYPT 2
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#define OSPF3_AUTH_HMAC 1 /* HMAC Cryptographic Authentication */
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/* OSPF neighbor states */
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#define NEIGHBOR_DOWN 0
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@ -459,10 +463,12 @@ struct ospf_neighbor
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#define OPT_MC 0x0004 /* Related to MOSPF, not used and obsolete */
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#define OPT_N 0x0008 /* Related to NSSA */
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#define OPT_P 0x0008 /* OSPFv2, flags P and N share position, see NSSA RFC */
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#define OPT_EA 0x0010 /* OSPFv2, external attributes, not used and obsolete */
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#define OPT_L_V2 0x0010 /* OSPFv2, link-local signaling, not used */
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#define OPT_R 0x0010 /* OSPFv3, originator is active router */
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#define OPT_DC 0x0020 /* Related to demand circuits, not used */
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#define OPT_AF 0x0100 /* OSPFv3 Address Families (RFC 5838) */
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#define OPT_L_V3 0x0200 /* OSPFv3, link-local signaling */
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#define OPT_AT 0x0400 /* OSPFv3, authentication trailer */
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/* Router-LSA VEB flags are are stored together with links (OSPFv2) or options (OSPFv3) */
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#define OPT_RT_B (0x01 << 24)
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@ -489,20 +495,38 @@ struct ospf_packet
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u8 autype; /* Undefined for OSPFv3 */
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};
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struct ospf_lls
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{
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u16 checksum;
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u16 length;
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byte data[0];
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};
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struct ospf_auth_crypto
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{
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u16 zero;
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u8 keyid;
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u8 len;
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u32 csn;
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u32 csn; /* Cryptographic sequence number (32-bit) */
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};
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union ospf_auth
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union ospf_auth2
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{
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u8 password[8];
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struct ospf_auth_crypto c32;
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};
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struct ospf_auth3
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{
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u16 type; /* Authentication type (OSPF3_AUTH_*) */
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u16 length; /* Authentication trailer length (header + data) */
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u16 reserved;
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u16 sa_id; /* Security association identifier (key_id) */
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u64 csn; /* Cryptographic sequence number (64-bit) */
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byte data[0]; /* Authentication data */
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};
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/* Packet types */
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#define HELLO_P 1 /* Hello */
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#define DBDES_P 2 /* Database description */
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@ -957,7 +981,7 @@ static inline void ospf_send_to_des(struct ospf_iface *ifa)
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#endif
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static inline uint ospf_pkt_hdrlen(struct ospf_proto *p)
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{ return ospf_is_v2(p) ? (sizeof(struct ospf_packet) + sizeof(union ospf_auth)) : sizeof(struct ospf_packet); }
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{ return ospf_is_v2(p) ? (sizeof(struct ospf_packet) + sizeof(union ospf_auth2)) : sizeof(struct ospf_packet); }
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static inline void * ospf_tx_buffer(struct ospf_iface *ifa)
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{ return ifa->sk->tbuf; }
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@ -969,11 +993,13 @@ static inline void * ospf_tx_buffer(struct ospf_iface *ifa)
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void ospf_send_hello(struct ospf_iface *ifa, int kind, struct ospf_neighbor *dirn);
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void ospf_receive_hello(struct ospf_packet *pkt, struct ospf_iface *ifa, struct ospf_neighbor *n, ip_addr faddr);
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uint ospf_hello3_options(struct ospf_packet *pkt);
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/* dbdes.c */
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void ospf_send_dbdes(struct ospf_proto *p, struct ospf_neighbor *n);
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void ospf_rxmt_dbdes(struct ospf_proto *p, struct ospf_neighbor *n);
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void ospf_receive_dbdes(struct ospf_packet *pkt, struct ospf_iface *ifa, struct ospf_neighbor *n);
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uint ospf_dbdes3_options(struct ospf_packet *pkt);
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/* lsreq.c */
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void ospf_send_lsreq(struct ospf_proto *p, struct ospf_neighbor *n);
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@ -29,23 +29,24 @@ ospf_pkt_fill_hdr(struct ospf_iface *ifa, void *buf, u8 h_type)
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pkt->areaid = htonl(ifa->oa->areaid);
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pkt->checksum = 0;
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pkt->instance_id = ifa->instance_id;
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pkt->autype = ifa->autype;
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pkt->autype = ospf_is_v2(p) ? ifa->autype : 0;
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}
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/* We assume OSPFv2 in ospf_pkt_finalize() */
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static void
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ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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ospf_pkt_finalize2(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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{
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struct ospf_proto *p = ifa->oa->po;
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struct password_item *pass = NULL;
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union ospf_auth *auth = (void *) (pkt + 1);
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pkt->checksum = 0;
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pkt->autype = ifa->autype;
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bzero(auth, sizeof(union ospf_auth));
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union ospf_auth2 *auth = (void *) (pkt + 1);
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memset(auth, 0, sizeof(union ospf_auth2));
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/* Compatibility note: auth may contain anything if autype is
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none, but nonzero values do not work with Mikrotik OSPF */
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pkt->checksum = 0;
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pkt->autype = ifa->autype;
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switch (ifa->autype)
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{
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case OSPF_AUTH_SIMPLE:
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@ -60,7 +61,7 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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case OSPF_AUTH_NONE:
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{
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void *body = (void *) (auth + 1);
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uint blen = *plen - sizeof(struct ospf_packet) - sizeof(union ospf_auth);
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uint blen = *plen - sizeof(struct ospf_packet) - sizeof(union ospf_auth2);
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pkt->checksum = ipsum_calculate(pkt, sizeof(struct ospf_packet), body, blen, NULL);
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}
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break;
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@ -69,7 +70,7 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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pass = password_find(ifa->passwords, 0);
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if (!pass)
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{
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log(L_ERR "No suitable password found for authentication");
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log(L_ERR "%s: No suitable password found for authentication", p->p.name);
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return;
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}
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@ -105,8 +106,7 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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else
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memset32(auth_tail, HMAC_MAGIC, auth_len / 4);
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mac_fill(pass->alg, pass->password, pass->length,
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(byte *) pkt, *plen, auth_tail);
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mac_fill(pass->alg, pass->password, pass->length, (byte *) pkt, *plen, auth_tail);
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break;
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default:
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@ -114,13 +114,63 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen)
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}
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}
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|
||||
/* We assume OSPFv2 in ospf_pkt_checkauth() */
|
||||
static int
|
||||
ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, uint len)
|
||||
/*
|
||||
* Return an extra packet size that should be added to a final packet size
|
||||
*/
|
||||
static void
|
||||
ospf_pkt_finalize3(struct ospf_iface *ifa, struct ospf_packet *pkt, uint *plen, ip_addr src)
|
||||
{
|
||||
struct ospf_proto *p = ifa->oa->po;
|
||||
union ospf_auth *auth = (void *) (pkt + 1);
|
||||
struct ospf_auth3 *auth = (void *) ((byte *) pkt + *plen);
|
||||
|
||||
pkt->checksum = 0;
|
||||
pkt->autype = 0;
|
||||
|
||||
if (ifa->autype != OSPF_AUTH_CRYPT)
|
||||
return;
|
||||
|
||||
struct password_item *pass = password_find(ifa->passwords, 0);
|
||||
if (!pass)
|
||||
{
|
||||
log(L_ERR "%s: No suitable password found for authentication", p->p.name);
|
||||
return;
|
||||
}
|
||||
|
||||
/* FIXME: Ensure persistence */
|
||||
p->csn64++;
|
||||
|
||||
uint mac_len = mac_type_length(pass->alg);
|
||||
uint auth_len = sizeof(struct ospf_auth3) + mac_len;
|
||||
*plen += auth_len;
|
||||
|
||||
ASSERT(*plen < ifa->sk->tbsize);
|
||||
|
||||
memset(auth, 0, sizeof(struct ospf_auth3));
|
||||
auth->type = htons(OSPF3_AUTH_HMAC);
|
||||
auth->length = htons(auth_len);
|
||||
auth->reserved = 0;
|
||||
auth->sa_id = htons(pass->id);
|
||||
put_u64(&auth->csn, p->csn64);
|
||||
|
||||
/* Initialize with src IP address padded with HMAC_MAGIC */
|
||||
put_ip6(auth->data, ipa_to_ip6(src));
|
||||
memset32(auth->data + 16, HMAC_MAGIC, (mac_len - 16) / 4);
|
||||
|
||||
/* Attach OSPFv3 Cryptographic Protocol ID to the key */
|
||||
uint pass_len = pass->length + 2;
|
||||
byte *pass_key = alloca(pass_len);
|
||||
memcpy(pass_key, pass->password, pass->length);
|
||||
put_u16(pass_key + pass->length, OSPF3_CRYPTO_ID);
|
||||
|
||||
mac_fill(pass->alg, pass_key, pass_len, (byte *) pkt, *plen, auth->data);
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
ospf_pkt_checkauth2(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, uint len)
|
||||
{
|
||||
struct ospf_proto *p = ifa->oa->po;
|
||||
union ospf_auth2 *auth = (void *) (pkt + 1);
|
||||
struct password_item *pass = NULL;
|
||||
const char *err_dsc = NULL;
|
||||
uint err_val = 0;
|
||||
|
|
@ -200,6 +250,119 @@ drop:
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int
|
||||
ospf_pkt_checkauth3(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, uint len, ip_addr src)
|
||||
{
|
||||
struct ospf_proto *p = ifa->oa->po;
|
||||
const char *err_dsc = NULL;
|
||||
uint err_val = 0;
|
||||
|
||||
uint plen = ntohs(pkt->length);
|
||||
uint opts, lls_present, auth_present;
|
||||
|
||||
/*
|
||||
* When autentication is not enabled, ignore the trailer. This is different
|
||||
* from OSPFv2, but it is necessary in order to support migration modes. Note
|
||||
* that regular authenticated packets do not have valid checksum and will be
|
||||
* dropped by OS on non-authenticated ifaces.
|
||||
*/
|
||||
if (ifa->autype != OSPF_AUTH_CRYPT)
|
||||
return 1;
|
||||
|
||||
switch(pkt->type)
|
||||
{
|
||||
case HELLO_P:
|
||||
opts = ospf_hello3_options(pkt);
|
||||
lls_present = opts & OPT_L_V3;
|
||||
auth_present = opts & OPT_AT;
|
||||
break;
|
||||
|
||||
case DBDES_P:
|
||||
opts = ospf_dbdes3_options(pkt);
|
||||
lls_present = opts & OPT_L_V3;
|
||||
auth_present = opts & OPT_AT;
|
||||
break;
|
||||
|
||||
default:
|
||||
lls_present = 0;
|
||||
auth_present = n->options & OPT_AT;
|
||||
}
|
||||
|
||||
if (!auth_present)
|
||||
DROP1("missing authentication trailer");
|
||||
|
||||
if (lls_present)
|
||||
{
|
||||
if ((plen + sizeof(struct ospf_lls)) > len)
|
||||
DROP("packet length mismatch", len);
|
||||
|
||||
struct ospf_lls *lls = (void *) ((byte *) pkt + plen);
|
||||
plen += ntohs(lls->length);
|
||||
}
|
||||
|
||||
if ((plen + sizeof(struct ospf_auth3)) > len)
|
||||
DROP("packet length mismatch", len);
|
||||
|
||||
struct ospf_auth3 *auth = (void *) ((byte *) pkt + plen);
|
||||
|
||||
uint rcv_auth_type = ntohs(auth->type);
|
||||
if (rcv_auth_type != OSPF3_AUTH_HMAC)
|
||||
DROP("authentication method mismatch", rcv_auth_type);
|
||||
|
||||
uint rcv_auth_len = ntohs(auth->length);
|
||||
if (plen + rcv_auth_len > len)
|
||||
DROP("packet length mismatch", len);
|
||||
|
||||
uint rcv_key_id = ntohs(auth->sa_id);
|
||||
struct password_item *pass = password_find_by_id(ifa->passwords, rcv_key_id);
|
||||
if (!pass)
|
||||
DROP("no suitable password found", rcv_key_id);
|
||||
|
||||
uint mac_len = mac_type_length(pass->alg);
|
||||
if (rcv_auth_len != (sizeof(struct ospf_auth3) + mac_len))
|
||||
DROP("wrong authentication length", rcv_auth_len);
|
||||
|
||||
uint pt = pkt->type - 1;
|
||||
u64 rcv_csn = get_u64(&auth->csn);
|
||||
if (n && (rcv_csn <= n->csn64[pt]))
|
||||
{
|
||||
/* We want to report both new and old CSN */
|
||||
LOG_PKT_AUTH("Authentication failed for nbr %R on %s - "
|
||||
"lower sequence number (rcv %u, old %u)",
|
||||
n->rid, ifa->ifname, (uint) rcv_csn, (uint) n->csn64[pt]);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Save the received authentication data */
|
||||
byte *auth_data = alloca(mac_len);
|
||||
memcpy(auth_data, auth->data, mac_len);
|
||||
|
||||
/* Initialize with src IP address padded with HMAC_MAGIC */
|
||||
put_ip6(auth->data, ipa_to_ip6(src));
|
||||
memset32(auth->data + 16, HMAC_MAGIC, (mac_len - 16) / 4);
|
||||
|
||||
/* Attach OSPFv3 Cryptographic Protocol ID to the key */
|
||||
uint pass_len = pass->length + 2;
|
||||
byte *pass_key = alloca(pass_len);
|
||||
memcpy(pass_key, pass->password, pass->length);
|
||||
put_u16(pass_key + pass->length, OSPF3_CRYPTO_ID);
|
||||
|
||||
if (!mac_verify(pass->alg, pass_key, pass_len,
|
||||
(byte *) pkt, plen + rcv_auth_len, auth_data))
|
||||
DROP("wrong authentication code", pass->id);
|
||||
|
||||
if (n)
|
||||
n->csn64[pt] = rcv_csn;
|
||||
|
||||
return 1;
|
||||
|
||||
drop:
|
||||
LOG_PKT_AUTH("Authentication failed for nbr %R on %s - %s (%u)",
|
||||
(n ? n->rid : ntohl(pkt->routerid)), ifa->ifname, err_dsc, err_val);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* ospf_rx_hook
|
||||
* @sk: socket we received the packet.
|
||||
|
|
@ -298,12 +461,12 @@ ospf_rx_hook(sock *sk, uint len)
|
|||
|
||||
if (ospf_is_v2(p) && (pkt->autype != OSPF_AUTH_CRYPT))
|
||||
{
|
||||
uint hlen = sizeof(struct ospf_packet) + sizeof(union ospf_auth);
|
||||
uint hlen = sizeof(struct ospf_packet) + sizeof(union ospf_auth2);
|
||||
uint blen = plen - hlen;
|
||||
void *body = ((void *) pkt) + hlen;
|
||||
|
||||
if (!ipsum_verify(pkt, sizeof(struct ospf_packet), body, blen, NULL))
|
||||
DROP1("invalid checksum");
|
||||
DROP("invalid checksum", ntohs(pkt->checksum));
|
||||
}
|
||||
|
||||
/* Third, we resolve associated iface and handle vlinks. */
|
||||
|
|
@ -401,8 +564,14 @@ found:
|
|||
return 1;
|
||||
}
|
||||
|
||||
/* Check packet type here, ospf_pkt_checkauth3() expects valid values */
|
||||
if (pkt->type < HELLO_P || pkt->type > LSACK_P)
|
||||
DROP("invalid packet type", pkt->type);
|
||||
|
||||
/* ospf_pkt_checkauth() has its own error logging */
|
||||
if (ospf_is_v2(p) && !ospf_pkt_checkauth(n, ifa, pkt, len))
|
||||
if ((ospf_is_v2(p) ?
|
||||
!ospf_pkt_checkauth2(n, ifa, pkt, len) :
|
||||
!ospf_pkt_checkauth3(n, ifa, pkt, len, sk->faddr)))
|
||||
return 1;
|
||||
|
||||
switch (pkt->type)
|
||||
|
|
@ -426,9 +595,6 @@ found:
|
|||
case LSACK_P:
|
||||
ospf_receive_lsack(pkt, ifa, n);
|
||||
break;
|
||||
|
||||
default:
|
||||
DROP("invalid packet type", pkt->type);
|
||||
};
|
||||
return 1;
|
||||
|
||||
|
|
@ -472,7 +638,9 @@ ospf_send_to(struct ospf_iface *ifa, ip_addr dst)
|
|||
uint plen = ntohs(pkt->length);
|
||||
|
||||
if (ospf_is_v2(ifa->oa->po))
|
||||
ospf_pkt_finalize(ifa, pkt, &plen);
|
||||
ospf_pkt_finalize2(ifa, pkt, &plen);
|
||||
else
|
||||
ospf_pkt_finalize3(ifa, pkt, &plen, sk->saddr);
|
||||
|
||||
int done = sk_send_to(sk, plen, dst, 0);
|
||||
if (!done)
|
||||
|
|
|
|||
Loading…
Reference in a new issue