X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=secnet.git;a=blobdiff_plain;f=site.c;h=a35bb049ab9ff724ed6c2aa8c8f273cab9331695;hp=2012c4a2a78376ac7bfb240fdedcdc38eec8b49e;hb=29ec8ffe50c96d8d54129d53fed33382f6ad4892;hpb=15efc8b65dfe32c10b2bbb93769973f1191ea815 diff --git a/site.c b/site.c index 2012c4a..a35bb04 100644 --- a/site.c +++ b/site.c @@ -41,6 +41,7 @@ #define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */ #define DEFAULT_MOBILE_PEERS_MAX 3 /* send at most this many copies (default) */ +#define DEFAULT_STATIC_PEERS_MAX 3 /* retain at most this many peer addresses */ /* Each site can be in one of several possible states. */ @@ -144,9 +145,6 @@ static struct flagstr log_event_table[]={ /* Details of "mobile peer" semantics: - | Note: this comment is wishful thinking right now. It will be - | implemented in subsequent commits. - - We use the same data structure for the different configurations, but manage it with different algorithms. @@ -220,8 +218,6 @@ static struct flagstr log_event_table[]={ */ -#define MAX_MOBILE_PEERS_MAX 5 /* send at most this many copies, compiled max */ - typedef struct { struct timeval last; struct comm_addr addr; @@ -231,7 +227,7 @@ typedef struct { /* configuration information */ /* runtime information */ int npeers; - transport_peer peers[MAX_MOBILE_PEERS_MAX]; + transport_peer peers[MAX_PEER_ADDRS]; } transport_peers; /* Basic operations on transport peer address sets */ @@ -249,7 +245,8 @@ static void transport_data_msgok(struct site *st, const struct comm_addr *a); * resolve completing (or being determined not to be relevant) or an * incoming PROD; if we are the responder, as a result of the MSG1. */ static bool_t transport_compute_setupinit_peers(struct site *st, - const struct comm_addr *configured_addr /* 0 if none or not found */, + const struct comm_addr *configured_addrs /* 0 if none or not found */, + int n_configured_addrs /* 0 if none or not found */, const struct comm_addr *incoming_packet_addr /* 0 if none */); /* Called if we are the responder in a key setup, when the resolve @@ -260,9 +257,9 @@ static bool_t transport_compute_setupinit_peers(struct site *st, * setup is done (either completed or not) and only the data peers are * relevant */ static void transport_resolve_complete(struct site *st, - const struct comm_addr *a); + const struct comm_addr *addrs, int naddrs); static void transport_resolve_complete_tardy(struct site *st, - const struct comm_addr *ca_use); + const struct comm_addr *addrs, int naddrs); static void transport_xmit(struct site *st, transport_peers *peers, struct buffer_if *buf, bool_t candebug); @@ -285,7 +282,7 @@ struct site { bool_t local_mobile, peer_mobile; /* Mobile client support */ int32_t transport_peers_max; string_t tunname; /* localname<->remotename by default, used in logs */ - string_t address; /* DNS name for bootstrapping, optional */ + cstring_t *addresses; /* DNS name or address(es) for bootstrapping, optional */ int remoteport; /* Port for bootstrapping, optional */ uint32_t mtu_target; struct netlink_if *netlink; @@ -320,7 +317,9 @@ struct site { uint32_t state; uint64_t now; /* Most recently seen time */ bool_t allow_send_prod; - bool_t resolving; + int resolving_count; + int resolving_n_results; + struct comm_addr resolving_results[MAX_PEER_ADDRS]; /* The currently established session */ struct data_key current; @@ -435,6 +434,7 @@ static bool_t initiate_key_setup(struct site *st, cstring_t reason, const struct comm_addr *prod_hint); static void enter_state_run(struct site *st); static bool_t enter_state_resolve(struct site *st); +static void decrement_resolving_count(struct site *st, int by); static bool_t enter_new_state(struct site *st,uint32_t next); static void enter_state_wait(struct site *st); static void activate_new_key(struct site *st); @@ -1195,30 +1195,56 @@ static bool_t send_msg(struct site *st) } } -static void site_resolve_callback(void *sst, struct in_addr *address) +static void site_resolve_callback(void *sst, const struct comm_addr *addrs, + int naddrs, const char *address, + const char *failwhy) { struct site *st=sst; - struct comm_addr ca_buf, *ca_use; - - st->resolving=False; - - if (address) { - FILLZERO(ca_buf); - ca_buf.comm=st->comms[0]; - ca_buf.sin.sin_family=AF_INET; - ca_buf.sin.sin_port=htons(st->remoteport); - ca_buf.sin.sin_addr=*address; - ca_use=&ca_buf; - slog(st,LOG_STATE,"resolution of %s completed: %s", - st->address, comm_addr_to_string(ca_use));; + + if (!naddrs) { + slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy); } else { - slog(st,LOG_ERROR,"resolution of %s failed",st->address); - ca_use=0; + slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s", + address, naddrs, comm_addr_to_string(&addrs[0]));; + + int n_tocopy = MIN(st->transport_peers_max - st->resolving_n_results, + naddrs); + memcpy(st->resolving_results + st->resolving_n_results, + addrs, + sizeof(st->resolving_results[0]) * n_tocopy); + st->resolving_n_results += naddrs; + } + + decrement_resolving_count(st,1); +} + +static void decrement_resolving_count(struct site *st, int by) +{ + assert(st->resolving_count>0); + st->resolving_count-=by; + + if (st->resolving_count) + return; + + /* OK, we are done with them all. Handle combined results. */ + + const struct comm_addr *addrs=st->resolving_results; + int naddrs=st->resolving_n_results; + + if (naddrs) { + slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s", + naddrs, comm_addr_to_string(&addrs[0]));; + if (st->resolving_n_results > st->transport_peers_max) { + slog(st,LOG_STATE,"resolution of supplied addresses/names" + " yielded too many results (%d > %d), some ignored", + st->resolving_n_results, st->transport_peers_max); + st->resolving_n_results=st->transport_peers_max; + } } switch (st->state) { case SITE_RESOLVE: - if (transport_compute_setupinit_peers(st,ca_use,0)) { + if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) { enter_new_state(st,SITE_SENTMSG1); } else { /* Can't figure out who to try to to talk to */ @@ -1230,38 +1256,36 @@ static void site_resolve_callback(void *sst, struct in_addr *address) case SITE_SENTMSG1: case SITE_SENTMSG2: case SITE_SENTMSG3: case SITE_SENTMSG4: case SITE_SENTMSG5: - if (ca_use) { + if (naddrs) { /* We start using the address immediately for data too. * It's best to store it in st->peers now because we might * go via SENTMSG5, WAIT, and a MSG0, straight into using * the new key (without updating the data peer addrs). */ - transport_resolve_complete(st,ca_use); + transport_resolve_complete(st,addrs,naddrs); } else if (st->local_mobile) { /* We can't let this rest because we may have a peer * address which will break in the future. */ - slog(st,LOG_SETUP_INIT,"resolution of %s failed: " - "abandoning key exchange",st->address); + slog(st,LOG_SETUP_INIT,"resolution failed: " + "abandoning key exchange"); enter_state_wait(st); } else { - slog(st,LOG_SETUP_INIT,"resolution of %s failed: " + slog(st,LOG_SETUP_INIT,"resolution failed: " " continuing to use source address of peer's packets" - " for key exchange and ultimately data", - st->address); + " for key exchange and ultimately data"); } break; case SITE_RUN: - if (ca_use) { - slog(st,LOG_SETUP_INIT,"resolution of %s completed tardily," - " updating peer address(es)",st->address); - transport_resolve_complete_tardy(st,ca_use); + if (naddrs) { + slog(st,LOG_SETUP_INIT,"resolution completed tardily," + " updating peer address(es)"); + transport_resolve_complete_tardy(st,addrs,naddrs); } else if (st->local_mobile) { /* Not very good. We should queue (another) renegotiation * so that we can update the peer address. */ st->key_renegotiate_time=st->now+st->wait_timeout; } else { - slog(st,LOG_SETUP_INIT,"resolution of %s failed: " - " continuing to use source address of peer's packets", - st->address); + slog(st,LOG_SETUP_INIT,"resolution failed: " + " continuing to use source address of peer's packets"); } break; case SITE_WAIT: @@ -1277,10 +1301,10 @@ static bool_t initiate_key_setup(struct site *st, cstring_t reason, /* Reentrancy hazard: can call enter_new_state/enter_state_* */ if (st->state!=SITE_RUN) return False; slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason); - if (st->address) { - slog(st,LOG_SETUP_INIT,"resolving peer address"); + if (st->addresses) { + slog(st,LOG_SETUP_INIT,"resolving peer address(es)"); return enter_state_resolve(st); - } else if (transport_compute_setupinit_peers(st,0,prod_hint)) { + } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) { return enter_new_state(st,SITE_SENTMSG1); } slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer"); @@ -1359,7 +1383,7 @@ static void set_link_quality(struct site *st) quality=LINK_QUALITY_UP; else if (st->state==SITE_WAIT || st->state==SITE_STOP) quality=LINK_QUALITY_DOWN; - else if (st->address) + else if (st->addresses) quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS; else if (transport_peers_valid(&st->peers)) quality=LINK_QUALITY_DOWN_STALE_ADDRESS; @@ -1389,22 +1413,35 @@ static bool_t ensure_resolving(struct site *st) { /* Reentrancy hazard: may call site_resolve_callback and hence * enter_new_state, enter_state_* and generate_msg*. */ - if (st->resolving) + if (st->resolving_count) return True; - assert(st->address); + assert(st->addresses); /* resolver->request might reentrantly call site_resolve_callback - * which will clear st->resolving, so we need to set it beforehand - * rather than afterwards; also, it might return False, in which - * case we have to clear ->resolving again. */ - st->resolving=True; - bool_t ok = st->resolver->request(st->resolver->st,st->address, - site_resolve_callback,st); - if (!ok) - st->resolving=False; - - return ok; + * which will decrement st->resolving, so we need to increment it + * twice beforehand to prevent decrement from thinking we're + * finished, and decrement it ourselves. Alternatively if + * everything fails then there are no callbacks due and we simply + * set it to 0 and return false.. */ + st->resolving_count+=2; + const char **addrp=st->addresses; + const char *address; + bool_t anyok=False; + for (; (address=*addrp++); ) { + bool_t ok = st->resolver->request(st->resolver->st,address, + st->remoteport,st->comms[0], + site_resolve_callback,st); + if (ok) + st->resolving_count++; + anyok|=ok; + } + if (!anyok) { + st->resolving_count=0; + return False; + } + decrement_resolving_count(st,2); + return True; } static bool_t enter_state_resolve(struct site *st) @@ -1679,11 +1716,11 @@ static bool_t site_incoming(void *sst, struct buffer_if *buf, if (st->state==SITE_RUN || st->state==SITE_RESOLVE || st->state==SITE_WAIT) { /* We should definitely process it */ - transport_compute_setupinit_peers(st,0,source); + transport_compute_setupinit_peers(st,0,0,source); if (process_msg1(st,buf,source,&named_msg)) { slog(st,LOG_SETUP_INIT,"key setup initiated by peer"); bool_t entered=enter_new_state(st,SITE_SENTMSG2); - if (entered && st->address && st->local_mobile) + if (entered && st->addresses && st->local_mobile) /* We must do this as the very last thing, because the resolver callback might reenter us. */ ensure_resolving(st); @@ -1943,8 +1980,8 @@ static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc); st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc); - st->address=dict_read_string(dict, "address", False, "site", loc); - if (st->address) + st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0); + if (st->addresses) st->remoteport=dict_read_number(dict,"port",True,"site",loc,0); else st->remoteport=0; st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc); @@ -1967,12 +2004,14 @@ static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, st->mobile_peer_expiry= dict_read_number( dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY); - st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number( - dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX); + const char *peerskey= st->peer_mobile + ? "mobile-peers-max" : "static-peers-max"; + st->transport_peers_max= dict_read_number( + dict,peerskey,False,"site",loc,DEFAULT_MOBILE_PEERS_MAX); if (st->transport_peers_max<1 || - st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) { - cfgfatal(loc,"site","mobile-peers-max must be in range 1.." - STRING(MAX_MOBILE_PEERS_MAX) "\n"); + st->transport_peers_max>=MAX_PEER_ADDRS) { + cfgfatal(loc,"site", "%s must be in range 1.." + STRING(MAX_PEER_ADDRS) "\n", peerskey); } if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2) @@ -1989,7 +2028,7 @@ static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, st->log_events=string_list_to_word(dict_lookup(dict,"log-events"), log_event_table,"site"); - st->resolving=False; + st->resolving_count=0; st->allow_send_prod=0; st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5, @@ -2092,13 +2131,9 @@ static void transport_peers_debug(struct site *st, transport_peers *dst, } } -static int transport_peer_compar(const void *av, const void *bv) { - const transport_peer *a=av; - const transport_peer *b=bv; - /* put most recent first in the array */ - if (timercmp(&a->last, &b->last, <)) return +1; - if (timercmp(&a->last, &b->last, >)) return -11; - return 0; +static bool_t transport_addrs_equal(const struct comm_addr *a, + const struct comm_addr *b) { + return !memcmp(a,b,sizeof(*a)); } static void transport_peers_expire(struct site *st, transport_peers *peers) { @@ -2114,73 +2149,105 @@ static void transport_peers_expire(struct site *st, transport_peers *peers) { transport_peers_debug(st,peers,"expire", 0,0,0); } -static void transport_record_peer(struct site *st, transport_peers *peers, - const struct comm_addr *addr, const char *m) { - int slot, changed=0; +static bool_t transport_peer_record_one(struct site *st, transport_peers *peers, + const struct comm_addr *ca, + const struct timeval *tv) { + /* returns false if output is full */ + int search; - for (slot=0; slotnpeers; slot++) - if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr))) - goto found; + if (peers->npeers > st->transport_peers_max) + return 0; - changed=1; - if (peers->npeers==st->transport_peers_max) - slot=st->transport_peers_max-1; - else - slot=peers->npeers++; + for (search=0; searchnpeers; search++) + if (transport_addrs_equal(&peers->peers[search].addr, ca)) + return 1; - found: - peers->peers[slot].addr=*addr; - peers->peers[slot].last=*tv_now; + peers->peers[peers->npeers].addr = *ca; + peers->peers[peers->npeers].last = *tv; + peers->npeers++; + return 1; +} - if (peers->npeers>1) - qsort(peers->peers, peers->npeers, - sizeof(*peers->peers), transport_peer_compar); +static void transport_record_peers(struct site *st, transport_peers *peers, + const struct comm_addr *addrs, int naddrs, + const char *m) { + /* We add addrs into peers. The new entries end up at the front + * and displace entries towards the end (perhaps even off the end). + * Any existing matching entries are moved up to the front. + * Caller must first call transport_peers_expire. */ - if (changed || peers->npeers!=1) - transport_peers_debug(st,peers,m, 1,addr,0); - transport_peers_expire(st, peers); + if (naddrs==1 && peers->npeers>=1 && + transport_addrs_equal(&addrs[0], &peers->peers[0].addr)) { + /* optimisation, also avoids debug for trivial updates */ + peers->peers[0].last = *tv_now; + return; + } + + int old_npeers=peers->npeers; + transport_peers old_peers[old_npeers]; + memcpy(old_peers,peers->peers,sizeof(old_npeers)); + + peers->npeers=0; + int i; + for (i=0; ipeers[i]; + if (!transport_peer_record_one(st,peers, &old->addr, &old->last)) + break; + } + + transport_peers_debug(st,peers,m, naddrs,addrs,0); } static bool_t transport_compute_setupinit_peers(struct site *st, - const struct comm_addr *configured_addr /* 0 if none or not found */, + const struct comm_addr *configured_addrs /* 0 if none or not found */, + int n_configured_addrs /* 0 if none or not found */, const struct comm_addr *incoming_packet_addr /* 0 if none */) { - - if (!configured_addr && !incoming_packet_addr && + if (!n_configured_addrs && !incoming_packet_addr && !transport_peers_valid(&st->peers)) return False; slog(st,LOG_SETUP_INIT, - "using:%s%s %d old peer address(es)", - configured_addr ? " configured address;" : "", + "using:%d configured addr(s);%s %d old peer addrs(es)", + n_configured_addrs, incoming_packet_addr ? " incoming packet address;" : "", st->peers.npeers); - /* Non-mobile peers have st->peers.npeers==0 or ==1, since they - * have transport_peers_max==1. The effect is that this code - * always uses the configured address if supplied, or otherwise - * the address of the incoming PROD, or the existing data peer if - * one exists; this is as desired. */ + /* Non-mobile peers try addresses until one is plausible. The + * effect is that this code always tries first the configured + * address if supplied, or otherwise the address of the incoming + * PROD, or finally the existing data peer if one exists; this is + * as desired. */ transport_peers_copy(st,&st->setup_peers,&st->peers); + transport_peers_expire(st,&st->setup_peers); if (incoming_packet_addr) - transport_record_peer(st,&st->setup_peers,incoming_packet_addr, - "incoming"); + transport_record_peers(st,&st->setup_peers, + incoming_packet_addr,1, "incoming"); - if (configured_addr) - transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit"); + if (n_configured_addrs) + transport_record_peers(st,&st->setup_peers, + configured_addrs,n_configured_addrs, "setupinit"); assert(transport_peers_valid(&st->setup_peers)); return True; } static void transport_setup_msgok(struct site *st, const struct comm_addr *a) { - if (st->peer_mobile) - transport_record_peer(st,&st->setup_peers,a,"setupmsg"); + if (st->peer_mobile) { + transport_peers_expire(st,&st->setup_peers); + transport_record_peers(st,&st->setup_peers,a,1,"setupmsg"); + } } static void transport_data_msgok(struct site *st, const struct comm_addr *a) { - if (st->peer_mobile) - transport_record_peer(st,&st->peers,a,"datamsg"); + if (st->peer_mobile) { + transport_peers_expire(st,&st->setup_peers); + transport_record_peers(st,&st->peers,a,1,"datamsg"); + } } static int transport_peers_valid(transport_peers *peers) { @@ -2199,14 +2266,19 @@ static void transport_peers_copy(struct site *st, transport_peers *dst, } static void transport_resolve_complete(struct site *st, - const struct comm_addr *ca_use) { - transport_record_peer(st,&st->peers,ca_use,"resolved data"); - transport_record_peer(st,&st->setup_peers,ca_use,"resolved setup"); + const struct comm_addr *addrs, + int naddrs) { + transport_peers_expire(st,&st->peers); + transport_record_peers(st,&st->peers,addrs,naddrs,"resolved data"); + transport_peers_expire(st,&st->setup_peers); + transport_record_peers(st,&st->setup_peers,addrs,naddrs,"resolved setup"); } static void transport_resolve_complete_tardy(struct site *st, - const struct comm_addr *ca_use) { - transport_record_peer(st,&st->peers,ca_use,"resolved tardily"); + const struct comm_addr *addrs, + int naddrs) { + transport_peers_expire(st,&st->peers); + transport_record_peers(st,&st->peers,addrs,naddrs,"resolved tardily"); } static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io, @@ -2229,7 +2301,7 @@ void transport_xmit(struct site *st, transport_peers *peers, int slot; transport_peers_expire(st, peers); unsigned failed=0; /* bitmask */ - assert(MAX_MOBILE_PEERS_MAX < sizeof(unsigned)*CHAR_BIT); + assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT); int nfailed=0; for (slot=0; slotnpeers; slot++) {