/* * DEBUG: section 12 Internet Cache Protocol (ICP) * AUTHOR: Duane Wessels * * SQUID Web Proxy Cache http://www.squid-cache.org/ * ---------------------------------------------------------- * * Squid is the result of efforts by numerous individuals from * the Internet community; see the CONTRIBUTORS file for full * details. Many organizations have provided support for Squid's * development; see the SPONSORS file for full details. Squid is * Copyrighted (C) 2001 by the Regents of the University of * California; see the COPYRIGHT file for full details. Squid * incorporates software developed and/or copyrighted by other * sources; see the CREDITS file for full details. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA. * */ /** \defgroup ServerProtocolICPInternal2 ICPv2 Internals \ingroup ServerProtocolICPAPI */ #include "squid.h" #include "Store.h" #include "comm.h" #include "ICP.h" #include "HttpRequest.h" #include "acl/FilledChecklist.h" #include "acl/Acl.h" #include "AccessLogEntry.h" #include "wordlist.h" #include "SquidTime.h" #include "SwapDir.h" #include "icmp/net_db.h" #include "ip/IpAddress.h" #include "ip/tools.h" #include "rfc1738.h" /// \ingroup ServerProtocolICPInternal2 static void icpLogIcp(const IpAddress &, log_type, int, const char *, int); /// \ingroup ServerProtocolICPInternal2 static void icpHandleIcpV2(int, IpAddress &, char *, int); /// \ingroup ServerProtocolICPInternal2 static void icpCount(void *, int, size_t, int); /** \ingroup ServerProtocolICPInternal2 * IcpQueueHead is global so comm_incoming() knows whether or not * to call icpUdpSendQueue. */ static icpUdpData *IcpQueueHead = NULL; /// \ingroup ServerProtocolICPInternal2 static icpUdpData *IcpQueueTail = NULL; /// \ingroup ServerProtocolICPInternal2 IpAddress theOutICPAddr; /* icp_common_t */ _icp_common_t::_icp_common_t() : opcode(ICP_INVALID), version(0), length(0), reqnum(0), flags(0), pad(0), shostid(0) {} _icp_common_t::_icp_common_t(char *buf, unsigned int len) { if (len < sizeof(_icp_common_t)) { /* mark as invalid */ length = len + 1; return; } xmemcpy(this, buf, sizeof(icp_common_t)); /* * Convert network order sensitive fields */ length = ntohs(length); reqnum = ntohl(reqnum); flags = ntohl(flags); pad = ntohl(pad); } icp_opcode _icp_common_t::getOpCode() const { if (opcode > (char)ICP_END) return ICP_INVALID; return (icp_opcode)opcode; } /* ICPState */ ICPState::ICPState(icp_common_t &aHeader, HttpRequest *aRequest): header(aHeader), request(HTTPMSGLOCK(aRequest)), fd(-1), url(NULL) {} ICPState::~ICPState() { safe_free(url); HTTPMSGUNLOCK(request); } /* End ICPState */ /* ICP2State */ /// \ingroup ServerProtocolICPInternal2 class ICP2State : public ICPState, public StoreClient { public: ICP2State(icp_common_t & aHeader, HttpRequest *aRequest): ICPState(aHeader, aRequest),rtt(0),src_rtt(0),flags(0) {} ~ICP2State(); void created(StoreEntry * newEntry); int rtt; int src_rtt; u_int32_t flags; }; ICP2State::~ICP2State() {} void ICP2State::created(StoreEntry *newEntry) { StoreEntry *entry = newEntry->isNull () ? NULL : newEntry; debugs(12, 5, "icpHandleIcpV2: OPCODE " << icp_opcode_str[header.opcode]); icp_opcode codeToSend; if (icpCheckUdpHit(entry, request)) { codeToSend = ICP_HIT; } else { #if USE_ICMP if (Config.onoff.test_reachability && rtt == 0) { if ((rtt = netdbHostRtt(request->GetHost())) == 0) netdbPingSite(request->GetHost()); } #endif /* USE_ICMP */ if (icpGetCommonOpcode() != ICP_ERR) codeToSend = icpGetCommonOpcode(); else if (Config.onoff.test_reachability && rtt == 0) codeToSend = ICP_MISS_NOFETCH; else codeToSend = ICP_MISS; } icpCreateAndSend(codeToSend, flags, url, header.reqnum, src_rtt, fd, from); delete this; } /* End ICP2State */ /// \ingroup ServerProtocolICPInternal2 static void icpLogIcp(const IpAddress &caddr, log_type logcode, int len, const char *url, int delay) { AccessLogEntry al; if (LOG_TAG_NONE == logcode) return; if (LOG_ICP_QUERY == logcode) return; clientdbUpdate(caddr, logcode, PROTO_ICP, len); if (!Config.onoff.log_udp) return; al.icp.opcode = ICP_QUERY; al.url = url; al.cache.caddr = caddr; al.cache.replySize = len; al.cache.code = logcode; al.cache.msec = delay; accessLogLog(&al, NULL); } /// \ingroup ServerProtocolICPInternal2 void icpUdpSendQueue(int fd, void *unused) { icpUdpData *q; int x; int delay; while ((q = IcpQueueHead) != NULL) { delay = tvSubUsec(q->queue_time, current_time); /* increment delay to prevent looping */ x = icpUdpSend(fd, q->address, (icp_common_t *) q->msg, q->logcode, ++delay); IcpQueueHead = q->next; safe_free(q); if (x < 0) break; } } _icp_common_t * _icp_common_t::createMessage( icp_opcode opcode, int flags, const char *url, int reqnum, int pad) { char *buf = NULL; icp_common_t *headerp = NULL; char *urloffset = NULL; int buf_len; buf_len = sizeof(icp_common_t) + strlen(url) + 1; if (opcode == ICP_QUERY) buf_len += sizeof(u_int32_t); buf = (char *) xcalloc(buf_len, 1); headerp = (icp_common_t *) (void *) buf; headerp->opcode = (char) opcode; headerp->version = ICP_VERSION_CURRENT; headerp->length = (u_int16_t) htons(buf_len); headerp->reqnum = htonl(reqnum); headerp->flags = htonl(flags); headerp->pad = htonl(pad); theOutICPAddr.GetInAddr( *((struct in_addr*)&headerp->shostid) ); urloffset = buf + sizeof(icp_common_t); if (opcode == ICP_QUERY) urloffset += sizeof(u_int32_t); xmemcpy(urloffset, url, strlen(url)); return (icp_common_t *)buf; } int icpUdpSend(int fd, const IpAddress &to, icp_common_t * msg, log_type logcode, int delay) { icpUdpData *queue; int x; int len; len = (int) ntohs(msg->length); debugs(12, 5, "icpUdpSend: FD " << fd << " sending " << icp_opcode_str[msg->opcode] << ", " << len << " bytes to " << to); x = comm_udp_sendto(fd, to, msg, len); if (x >= 0) { /* successfully written */ icpLogIcp(to, logcode, len, (char *) (msg + 1), delay); icpCount(msg, SENT, (size_t) len, delay); safe_free(msg); } else if (0 == delay) { /* send failed, but queue it */ queue = (icpUdpData *) xcalloc(1, sizeof(icpUdpData)); queue->address = to; queue->msg = msg; queue->len = (int) ntohs(msg->length); queue->queue_time = current_time; queue->logcode = logcode; if (IcpQueueHead == NULL) { IcpQueueHead = queue; IcpQueueTail = queue; } else if (IcpQueueTail == IcpQueueHead) { IcpQueueTail = queue; IcpQueueHead->next = queue; } else { IcpQueueTail->next = queue; IcpQueueTail = queue; } commSetSelect(fd, COMM_SELECT_WRITE, icpUdpSendQueue, NULL, 0); statCounter.icp.replies_queued++; } else { /* don't queue it */ statCounter.icp.replies_dropped++; } return x; } int icpCheckUdpHit(StoreEntry * e, HttpRequest * request) { if (e == NULL) return 0; if (!e->validToSend()) return 0; if (Config.onoff.icp_hit_stale) return 1; if (refreshCheckICP(e, request)) return 0; return 1; } /** * This routine selects an ICP opcode for ICP misses. * \retval ICP_ERR no opcode selected here \retval ICP_MISS_NOFETCH store is rebuilding, no fetch is possible yet */ icp_opcode icpGetCommonOpcode() { /* if store is rebuilding, return a UDP_MISS_NOFETCH */ if ((StoreController::store_dirs_rebuilding && opt_reload_hit_only) || hit_only_mode_until > squid_curtime) { return ICP_MISS_NOFETCH; } return ICP_ERR; } log_type icpLogFromICPCode(icp_opcode opcode) { if (opcode == ICP_ERR) return LOG_UDP_INVALID; if (opcode == ICP_DENIED) return LOG_UDP_DENIED; if (opcode == ICP_HIT) return LOG_UDP_HIT; if (opcode == ICP_MISS) return LOG_UDP_MISS; if (opcode == ICP_MISS_NOFETCH) return LOG_UDP_MISS_NOFETCH; fatal("expected ICP opcode\n"); return LOG_UDP_INVALID; } void icpCreateAndSend(icp_opcode opcode, int flags, char const *url, int reqnum, int pad, int fd, const IpAddress &from) { icp_common_t *reply = _icp_common_t::createMessage(opcode, flags, url, reqnum, pad); icpUdpSend(fd, from, reply, icpLogFromICPCode(opcode), 0); } void icpDenyAccess(IpAddress &from, char *url, int reqnum, int fd) { debugs(12, 2, "icpDenyAccess: Access Denied for " << from << " by " << AclMatchedName << "."); if (clientdbCutoffDenied(from)) { /* * count this DENIED query in the clientdb, even though * we're not sending an ICP reply... */ clientdbUpdate(from, LOG_UDP_DENIED, PROTO_ICP, 0); } else { icpCreateAndSend(ICP_DENIED, 0, url, reqnum, 0, fd, from); } } int icpAccessAllowed(IpAddress &from, HttpRequest * icp_request) { /* absent an explicit allow, we deny all */ if (!Config.accessList.icp) return 0; ACLFilledChecklist checklist(Config.accessList.icp, icp_request, NULL); checklist.src_addr = from; checklist.my_addr.SetNoAddr(); int result = checklist.fastCheck(); return result; } char const * icpGetUrlToSend(char *url) { if (strpbrk(url, w_space)) return rfc1738_escape(url); else return url; } HttpRequest * icpGetRequest(char *url, int reqnum, int fd, IpAddress &from) { if (strpbrk(url, w_space)) { url = rfc1738_escape(url); icpCreateAndSend(ICP_ERR, 0, rfc1738_escape(url), reqnum, 0, fd, from); return NULL; } HttpRequest *result; if ((result = HttpRequest::CreateFromUrl(url)) == NULL) icpCreateAndSend(ICP_ERR, 0, url, reqnum, 0, fd, from); return result; } static void doV2Query(int fd, IpAddress &from, char *buf, icp_common_t header) { int rtt = 0; int src_rtt = 0; u_int32_t flags = 0; /* We have a valid packet */ char *url = buf + sizeof(icp_common_t) + sizeof(u_int32_t); HttpRequest *icp_request = icpGetRequest(url, header.reqnum, fd, from); if (!icp_request) return; HTTPMSGLOCK(icp_request); if (!icpAccessAllowed(from, icp_request)) { icpDenyAccess(from, url, header.reqnum, fd); HTTPMSGUNLOCK(icp_request); return; } #if USE_ICMP if (header.flags & ICP_FLAG_SRC_RTT) { rtt = netdbHostRtt(icp_request->GetHost()); int hops = netdbHostHops(icp_request->GetHost()); src_rtt = ((hops & 0xFFFF) << 16) | (rtt & 0xFFFF); if (rtt) flags |= ICP_FLAG_SRC_RTT; } #endif /* USE_ICMP */ /* The peer is allowed to use this cache */ ICP2State *state = new ICP2State (header, icp_request); state->fd = fd; state->from = from; state->url = xstrdup (url); state->flags = flags; state->rtt = rtt; state->src_rtt = src_rtt; StoreEntry::getPublic (state, url, METHOD_GET); HTTPMSGUNLOCK(icp_request); } void _icp_common_t::handleReply(char *buf, IpAddress &from) { if (neighbors_do_private_keys && reqnum == 0) { debugs(12, 0, "icpHandleIcpV2: Neighbor " << from << " returned reqnum = 0"); debugs(12, 0, "icpHandleIcpV2: Disabling use of private keys"); neighbors_do_private_keys = 0; } char *url = buf + sizeof(icp_common_t); debugs(12, 3, "icpHandleIcpV2: " << icp_opcode_str[opcode] << " from " << from << " for '" << url << "'"); const cache_key *key = icpGetCacheKey(url, (int) reqnum); /* call neighborsUdpAck even if ping_status != PING_WAITING */ neighborsUdpAck(key, this, from); } static void icpHandleIcpV2(int fd, IpAddress &from, char *buf, int len) { if (len <= 0) { debugs(12, 3, "icpHandleIcpV2: ICP message is too small"); return; } icp_common_t header(buf, len); /* * Length field should match the number of bytes read */ if (len != header.length) { debugs(12, 3, "icpHandleIcpV2: ICP message is too small"); return; } switch (header.opcode) { case ICP_QUERY: /* We have a valid packet */ doV2Query(fd, from, buf, header); break; case ICP_HIT: case ICP_DECHO: case ICP_MISS: case ICP_DENIED: case ICP_MISS_NOFETCH: header.handleReply(buf, from); break; case ICP_INVALID: case ICP_ERR: break; default: debugs(12, 0, "icpHandleIcpV2: UNKNOWN OPCODE: " << header.opcode << " from " << from); break; } } #ifdef ICP_PKT_DUMP static void icpPktDump(icp_common_t * pkt) { IpAddress a; debugs(12, 9, "opcode: " << std::setw(3) << pkt->opcode << " " << icp_opcode_str[pkt->opcode]); debugs(12, 9, "version: "<< std::left << std::setw(8) << pkt->version); debugs(12, 9, "length: "<< std::left << std::setw(8) << ntohs(pkt->length)); debugs(12, 9, "reqnum: "<< std::left << std::setw(8) << ntohl(pkt->reqnum)); debugs(12, 9, "flags: "<< std::left << std::hex << std::setw(8) << ntohl(pkt->flags)); a = (struct in_addr)pkt->shostid; debugs(12, 9, "shostid: " << a ); debugs(12, 9, "payload: " << (char *) pkt + sizeof(icp_common_t)); } #endif void icpHandleUdp(int sock, void *data) { int *N = &incoming_sockets_accepted; IpAddress from; LOCAL_ARRAY(char, buf, SQUID_UDP_SO_RCVBUF); int len; int icp_version; int max = INCOMING_ICP_MAX; commSetSelect(sock, COMM_SELECT_READ, icpHandleUdp, NULL, 0); while (max--) { len = comm_udp_recvfrom(sock, buf, SQUID_UDP_SO_RCVBUF - 1, 0, from); if (len == 0) break; if (len < 0) { if (ignoreErrno(errno)) break; #ifdef _SQUID_LINUX_ /* Some Linux systems seem to set the FD for reading and then * return ECONNREFUSED when sendto() fails and generates an ICMP * port unreachable message. */ /* or maybe an EHOSTUNREACH "No route to host" message */ if (errno != ECONNREFUSED && errno != EHOSTUNREACH) #endif debugs(50, 1, "icpHandleUdp: FD " << sock << " recvfrom: " << xstrerror()); break; } (*N)++; icpCount(buf, RECV, (size_t) len, 0); buf[len] = '\0'; debugs(12, 4, "icpHandleUdp: FD " << sock << ": received " << (unsigned long int)len << " bytes from " << from); #ifdef ICP_PACKET_DUMP icpPktDump(buf); #endif if ((size_t) len < sizeof(icp_common_t)) { debugs(12, 4, "icpHandleUdp: Ignoring too-small UDP packet"); break; } icp_version = (int) buf[1]; /* cheat! */ if (icp_version == ICP_VERSION_2) icpHandleIcpV2(sock, from, buf, len); else if (icp_version == ICP_VERSION_3) icpHandleIcpV3(sock, from, buf, len); else debugs(12, 1, "WARNING: Unused ICP version " << icp_version << " received from " << from); } } void icpConnectionsOpen(void) { u_int16_t port; IpAddress addr; struct addrinfo *xai = NULL; int x; wordlist *s; if ((port = Config.Port.icp) <= 0) return; enter_suid(); addr = Config.Addrs.udp_incoming; addr.SetPort(port); if (!Ip::EnableIpv6 && !addr.SetIPv4()) { debugs(12, DBG_CRITICAL, "ERROR: IPv6 is disabled. " << addr << " is not an IPv4 address."); fatal("ICP port cannot be opened."); } /* split-stack for now requires default IPv4-only ICP */ if (Ip::EnableIpv6&IPV6_SPECIAL_SPLITSTACK && addr.IsAnyAddr()) { addr.SetIPv4(); } theInIcpConnection = comm_open_listener(SOCK_DGRAM, IPPROTO_UDP, addr, COMM_NONBLOCKING, "ICP Socket"); leave_suid(); if (theInIcpConnection < 0) fatal("Cannot open ICP Port"); commSetSelect(theInIcpConnection, COMM_SELECT_READ, icpHandleUdp, NULL, 0); for (s = Config.mcast_group_list; s; s = s->next) ipcache_nbgethostbyname(s->key, mcastJoinGroups, NULL); debugs(12, 1, "Accepting ICP messages at " << addr << ", FD " << theInIcpConnection << "."); addr.SetEmpty(); // clear for next use. addr = Config.Addrs.udp_outgoing; if ( !addr.IsNoAddr() ) { enter_suid(); addr.SetPort(port); if (!Ip::EnableIpv6 && !addr.SetIPv4()) { debugs(49, DBG_CRITICAL, "ERROR: IPv6 is disabled. " << addr << " is not an IPv4 address."); fatal("ICP port cannot be opened."); } /* split-stack for now requires default IPv4-only ICP */ if (Ip::EnableIpv6&IPV6_SPECIAL_SPLITSTACK && addr.IsAnyAddr()) { addr.SetIPv4(); } theOutIcpConnection = comm_open_listener(SOCK_DGRAM, IPPROTO_UDP, addr, COMM_NONBLOCKING, "ICP Port"); leave_suid(); if (theOutIcpConnection < 0) fatal("Cannot open Outgoing ICP Port"); commSetSelect(theOutIcpConnection, COMM_SELECT_READ, icpHandleUdp, NULL, 0); debugs(12, 1, "Outgoing ICP messages on port " << addr.GetPort() << ", FD " << theOutIcpConnection << "."); fd_note(theOutIcpConnection, "Outgoing ICP socket"); fd_note(theInIcpConnection, "Incoming ICP socket"); } else { theOutIcpConnection = theInIcpConnection; } theOutICPAddr.SetEmpty(); theOutICPAddr.InitAddrInfo(xai); x = getsockname(theOutIcpConnection, xai->ai_addr, &xai->ai_addrlen); if (x < 0) debugs(50, 1, "theOutIcpConnection FD " << theOutIcpConnection << ": getsockname: " << xstrerror()); else theOutICPAddr = *xai; theOutICPAddr.FreeAddrInfo(xai); } /** * icpConnectionShutdown only closes the 'in' socket if it is * different than the 'out' socket. */ void icpConnectionShutdown(void) { if (theInIcpConnection < 0) return; if (theInIcpConnection != theOutIcpConnection) { debugs(12, 1, "FD " << theInIcpConnection << " Closing ICP connection"); comm_close(theInIcpConnection); } /** * Here we set 'theInIcpConnection' to -1 even though the ICP 'in' * and 'out' sockets might be just one FD. This prevents this * function from executing repeatedly. When we are really ready to * exit or restart, main will comm_close the 'out' descriptor. */ theInIcpConnection = -1; /** * Normally we only write to the outgoing ICP socket, but * we also have a read handler there to catch messages sent * to that specific interface. During shutdown, we must * disable reading on the outgoing socket. */ assert(theOutIcpConnection > -1); commSetSelect(theOutIcpConnection, COMM_SELECT_READ, NULL, NULL, 0); } void icpConnectionClose(void) { icpConnectionShutdown(); if (theOutIcpConnection > -1) { debugs(12, 1, "FD " << theOutIcpConnection << " Closing ICP connection"); comm_close(theOutIcpConnection); theOutIcpConnection = -1; } } static void icpCount(void *buf, int which, size_t len, int delay) { icp_common_t *icp = (icp_common_t *) buf; if (len < sizeof(*icp)) return; if (SENT == which) { statCounter.icp.pkts_sent++; kb_incr(&statCounter.icp.kbytes_sent, len); if (ICP_QUERY == icp->opcode) { statCounter.icp.queries_sent++; kb_incr(&statCounter.icp.q_kbytes_sent, len); } else { statCounter.icp.replies_sent++; kb_incr(&statCounter.icp.r_kbytes_sent, len); /* this is the sent-reply service time */ statHistCount(&statCounter.icp.reply_svc_time, delay); } if (ICP_HIT == icp->opcode) statCounter.icp.hits_sent++; } else if (RECV == which) { statCounter.icp.pkts_recv++; kb_incr(&statCounter.icp.kbytes_recv, len); if (ICP_QUERY == icp->opcode) { statCounter.icp.queries_recv++; kb_incr(&statCounter.icp.q_kbytes_recv, len); } else { statCounter.icp.replies_recv++; kb_incr(&statCounter.icp.r_kbytes_recv, len); /* statCounter.icp.query_svc_time set in clientUpdateCounters */ } if (ICP_HIT == icp->opcode) statCounter.icp.hits_recv++; } } #define N_QUERIED_KEYS 8192 #define N_QUERIED_KEYS_MASK 8191 static cache_key queried_keys[N_QUERIED_KEYS][SQUID_MD5_DIGEST_LENGTH]; int icpSetCacheKey(const cache_key * key) { static int reqnum = 0; if (++reqnum < 0) reqnum = 1; storeKeyCopy(queried_keys[reqnum & N_QUERIED_KEYS_MASK], key); return reqnum; } const cache_key * icpGetCacheKey(const char *url, int reqnum) { if (neighbors_do_private_keys && reqnum) return queried_keys[reqnum & N_QUERIED_KEYS_MASK]; return storeKeyPublic(url, METHOD_GET); }