/* * $Id: icp_v2.c,v 1.72 2006/06/25 15:53:14 serassio Exp $ * * DEBUG: section 12 Internet Cache Protocol * 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. * */ #include "squid.h" static void icpLogIcp(struct in_addr, log_type, int, const char *, int); static void icpHandleIcpV2(int, struct sockaddr_in, char *, int); static void icpCount(void *, int, size_t, int); /* * IcpQueueHead is global so comm_incoming() knows whether or not * to call icpUdpSendQueue. */ static icpUdpData *IcpQueueTail = NULL; static void icpLogIcp(struct in_addr 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; memset(&al, '\0', sizeof(al)); al.icp.opcode = ICP_QUERY; al.url = url; al.cache.caddr = caddr; al.cache.size = len; al.cache.code = logcode; al.cache.msec = delay; accessLogLog(&al, NULL); } 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, q->msg, q->logcode, ++delay); IcpQueueHead = q->next; safe_free(q); if (x < 0) break; } } void * icpCreateMessage( 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_num32); buf = xcalloc(buf_len, 1); headerp = (icp_common_t *) (void *) buf; headerp->opcode = (char) opcode; headerp->version = ICP_VERSION_CURRENT; headerp->length = (u_short) htons(buf_len); headerp->reqnum = htonl(reqnum); headerp->flags = htonl(flags); headerp->pad = htonl(pad); headerp->shostid = theOutICPAddr.s_addr; urloffset = buf + sizeof(icp_common_t); if (opcode == ICP_QUERY) urloffset += sizeof(u_num32); xmemcpy(urloffset, url, strlen(url)); return buf; } int icpUdpSend(int fd, const struct sockaddr_in *to, icp_common_t * msg, log_type logcode, int delay) { icpUdpData *queue; int x; int len; len = (int) ntohs(msg->length); debug(12, 5) ("icpUdpSend: FD %d sending %s, %d bytes to %s:%d\n", fd, icp_opcode_str[msg->opcode], len, inet_ntoa(to->sin_addr), ntohs(to->sin_port)); x = comm_udp_sendto(fd, to, sizeof(*to), msg, len); if (x >= 0) { /* successfully written */ icpLogIcp(to->sin_addr, 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 = 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, request_t * request) { if (e == NULL) return 0; if (!storeEntryValidToSend(e)) return 0; if (Config.onoff.icp_hit_stale) return 1; if (refreshCheckICP(e, request)) return 0; return 1; } static void icpHandleIcpV2(int fd, struct sockaddr_in from, char *buf, int len) { icp_common_t header; StoreEntry *entry = NULL; char *url = NULL; const cache_key *key; request_t *icp_request = NULL; int allow = 0; aclCheck_t checklist; icp_common_t *reply; int src_rtt = 0; u_num32 flags = 0; int rtt = 0; int hops = 0; xmemcpy(&header, buf, sizeof(icp_common_t)); /* * Only these fields need to be converted */ header.length = ntohs(header.length); header.reqnum = ntohl(header.reqnum); header.flags = ntohl(header.flags); header.pad = ntohl(header.pad); /* * Length field should match the number of bytes read */ if (len != header.length) { debug(12, 3) ("icpHandleIcpV2: ICP message is too small\n"); return; } switch (header.opcode) { case ICP_QUERY: /* We have a valid packet */ url = buf + sizeof(icp_common_t) + sizeof(u_num32); if (strpbrk(url, w_space)) { url = rfc1738_escape(url); reply = icpCreateMessage(ICP_ERR, 0, url, header.reqnum, 0); icpUdpSend(fd, &from, reply, LOG_UDP_INVALID, 0); break; } if ((icp_request = urlParse(METHOD_GET, url)) == NULL) { reply = icpCreateMessage(ICP_ERR, 0, url, header.reqnum, 0); icpUdpSend(fd, &from, reply, LOG_UDP_INVALID, 0); break; } memset(&checklist, '\0', sizeof(checklist)); checklist.src_addr = from.sin_addr; checklist.my_addr = no_addr; checklist.request = icp_request; allow = aclCheckFast(Config.accessList.icp, &checklist); if (!allow) { debug(12, 2) ("icpHandleIcpV2: Access Denied for %s by %s.\n", inet_ntoa(from.sin_addr), AclMatchedName); if (clientdbCutoffDenied(from.sin_addr)) { /* * count this DENIED query in the clientdb, even though * we're not sending an ICP reply... */ clientdbUpdate(from.sin_addr, LOG_UDP_DENIED, PROTO_ICP, 0); } else { reply = icpCreateMessage(ICP_DENIED, 0, url, header.reqnum, 0); icpUdpSend(fd, &from, reply, LOG_UDP_DENIED, 0); } break; } if (header.flags & ICP_FLAG_SRC_RTT) { rtt = netdbHostRtt(icp_request->host); hops = netdbHostHops(icp_request->host); src_rtt = ((hops & 0xFFFF) << 16) | (rtt & 0xFFFF); if (rtt) flags |= ICP_FLAG_SRC_RTT; } /* The peer is allowed to use this cache */ entry = storeGetPublic(url, METHOD_GET); debug(12, 5) ("icpHandleIcpV2: OPCODE %s\n", icp_opcode_str[header.opcode]); if (icpCheckUdpHit(entry, icp_request)) { reply = icpCreateMessage(ICP_HIT, flags, url, header.reqnum, src_rtt); icpUdpSend(fd, &from, reply, LOG_UDP_HIT, 0); break; } if (Config.onoff.test_reachability && rtt == 0) { if ((rtt = netdbHostRtt(icp_request->host)) == 0) netdbPingSite(icp_request->host); } /* if store is rebuilding, return a UDP_HIT, but not a MISS */ if (store_dirs_rebuilding && opt_reload_hit_only) { reply = icpCreateMessage(ICP_MISS_NOFETCH, flags, url, header.reqnum, src_rtt); icpUdpSend(fd, &from, reply, LOG_UDP_MISS_NOFETCH, 0); } else if (hit_only_mode_until > squid_curtime) { reply = icpCreateMessage(ICP_MISS_NOFETCH, flags, url, header.reqnum, src_rtt); icpUdpSend(fd, &from, reply, LOG_UDP_MISS_NOFETCH, 0); } else if (Config.onoff.test_reachability && rtt == 0) { reply = icpCreateMessage(ICP_MISS_NOFETCH, flags, url, header.reqnum, src_rtt); icpUdpSend(fd, &from, reply, LOG_UDP_MISS_NOFETCH, 0); } else { reply = icpCreateMessage(ICP_MISS, flags, url, header.reqnum, src_rtt); icpUdpSend(fd, &from, reply, LOG_UDP_MISS, 0); } break; case ICP_HIT: #if ALLOW_SOURCE_PING case ICP_SECHO: #endif case ICP_DECHO: case ICP_MISS: case ICP_DENIED: case ICP_MISS_NOFETCH: if (neighbors_do_private_keys && header.reqnum == 0) { debug(12, 0) ("icpHandleIcpV2: Neighbor %s returned reqnum = 0\n", inet_ntoa(from.sin_addr)); debug(12, 0) ("icpHandleIcpV2: Disabling use of private keys\n"); neighbors_do_private_keys = 0; } url = buf + sizeof(icp_common_t); debug(12, 3) ("icpHandleIcpV2: %s from %s for '%s'\n", icp_opcode_str[header.opcode], inet_ntoa(from.sin_addr), url); key = icpGetCacheKey(url, (int) header.reqnum); /* call neighborsUdpAck even if ping_status != PING_WAITING */ neighborsUdpAck(key, &header, &from); break; case ICP_INVALID: case ICP_ERR: break; default: debug(12, 0) ("icpHandleIcpV2: UNKNOWN OPCODE: %d from %s\n", header.opcode, inet_ntoa(from.sin_addr)); break; } if (icp_request) requestDestroy(icp_request); } #ifdef ICP_PKT_DUMP static void icpPktDump(icp_common_t * pkt) { struct in_addr a; debug(12, 9) ("opcode: %3d %s\n", (int) pkt->opcode, icp_opcode_str[pkt->opcode]); debug(12, 9) ("version: %-8d\n", (int) pkt->version); debug(12, 9) ("length: %-8d\n", (int) ntohs(pkt->length)); debug(12, 9) ("reqnum: %-8d\n", ntohl(pkt->reqnum)); debug(12, 9) ("flags: %-8x\n", ntohl(pkt->flags)); a.s_addr = pkt->shostid; debug(12, 9) ("shostid: %s\n", inet_ntoa(a)); debug(12, 9) ("payload: %s\n", (char *) pkt + sizeof(icp_common_t)); } #endif void icpHandleUdp(int sock, void *data) { int *N = &incoming_sockets_accepted; struct sockaddr_in from; socklen_t from_len; 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--) { from_len = sizeof(from); memset(&from, '\0', from_len); statCounter.syscalls.sock.recvfroms++; len = recvfrom(sock, buf, SQUID_UDP_SO_RCVBUF - 1, 0, (struct sockaddr *) &from, &from_len); 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 debug(12, 1) ("icpHandleUdp: FD %d recvfrom: %s\n", sock, xstrerror()); break; } (*N)++; icpCount(buf, RECV, (size_t) len, 0); buf[len] = '\0'; debug(12, 4) ("icpHandleUdp: FD %d: received %d bytes from %s.\n", sock, len, inet_ntoa(from.sin_addr)); #ifdef ICP_PACKET_DUMP icpPktDump(buf); #endif if (len < sizeof(icp_common_t)) { debug(12, 4) ("icpHandleUdp: Ignoring too-small UDP packet\n"); 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 debug(12, 1) ("WARNING: Unused ICP version %d received from %s:%d\n", icp_version, inet_ntoa(from.sin_addr), ntohs(from.sin_port)); } } void icpConnectionsOpen(void) { u_short port; struct in_addr addr; struct sockaddr_in xaddr; int x; socklen_t len; wordlist *s; if ((port = Config.Port.icp) <= 0) return; enter_suid(); theInIcpConnection = comm_open(SOCK_DGRAM, IPPROTO_UDP, Config.Addrs.udp_incoming, port, 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); debug(12, 1) ("Accepting ICP messages at %s, port %d, FD %d.\n", inet_ntoa(Config.Addrs.udp_incoming), (int) port, theInIcpConnection); if ((addr = Config.Addrs.udp_outgoing).s_addr != no_addr.s_addr) { enter_suid(); theOutIcpConnection = comm_open(SOCK_DGRAM, IPPROTO_UDP, addr, port, COMM_NONBLOCKING, "ICP Port"); leave_suid(); if (theOutIcpConnection < 0) fatal("Cannot open Outgoing ICP Port"); commSetSelect(theOutIcpConnection, COMM_SELECT_READ, icpHandleUdp, NULL, 0); debug(12, 1) ("Outgoing ICP messages on port %d, FD %d.\n", (int) port, theOutIcpConnection); fd_note(theOutIcpConnection, "Outgoing ICP socket"); fd_note(theInIcpConnection, "Incoming ICP socket"); } else { theOutIcpConnection = theInIcpConnection; } memset(&theOutICPAddr, '\0', sizeof(struct in_addr)); len = sizeof(struct sockaddr_in); memset(&xaddr, '\0', len); x = getsockname(theOutIcpConnection, (struct sockaddr *) &xaddr, &len); if (x < 0) debug(12, 1) ("theOutIcpConnection FD %d: getsockname: %s\n", theOutIcpConnection, xstrerror()); else theOutICPAddr = xaddr.sin_addr; } /* * icpConnectionShutdown only closes the 'in' socket if it is * different than the 'out' socket. */ void icpConnectionShutdown(void) { if (theInIcpConnection < 0) return; if (theInIcpConnection != theOutIcpConnection) { debug(12, 1) ("FD %d Closing ICP connection\n", theInIcpConnection); 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) { debug(12, 1) ("FD %d Closing ICP connection\n", theOutIcpConnection); comm_close(theOutIcpConnection); theOutIcpConnection = -1; } } static void icpCount(void *buf, int which, size_t len, int delay) { icp_common_t *icp = 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][MD5_DIGEST_CHARS]; 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); }