/* * clamav-milter.c * .../clamav-milter/clamav-milter.c * * Copyright (C) 2003 Nigel Horne * * 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., 675 Mass Ave, Cambridge, MA 02139, USA. * * Install into /usr/local/sbin/clamav-milter * * For installation instructions see the file INSTALL that came with this file */ static char const rcsid[] = "$Id: clamav-milter.c,v 1.200 2005/05/12 07:31:09 nigelhorne Exp $"; #define CM_VERSION "0.85" #if HAVE_CONFIG_H #include "clamav-config.h" #endif #include "defaults.h" #include "cfgparser.h" #include "target.h" #include "str.h" #include "../libclamav/others.h" #include "strrcpy.h" #include "clamav.h" #include "../libclamav/table.h" #ifndef CL_DEBUG #define NDEBUG #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if HAVE_MMAP #if HAVE_SYS_MMAN_H #include #else /* HAVE_SYS_MMAN_H */ #undef HAVE_MMAP #endif #endif #ifdef C_LINUX #include #include #include #define gettext_noop(s) s #define _(s) gettext(s) #define N_(s) gettext_noop(s) #else #define _(s) s #define N_(s) s #endif #ifdef WITH_TCPWRAP #include int allow_severity = LOG_DEBUG; int deny_severity = LOG_NOTICE; #endif #ifndef CL_DEBUG static const char *logFile; static int logTime; static char console[] = "/dev/console"; #endif #if defined(CL_DEBUG) && defined(C_LINUX) #include #endif #define _GNU_SOURCE #include #ifndef SENDMAIL_BIN #define SENDMAIL_BIN "/usr/lib/sendmail" #endif #ifndef HAVE_IN_PORT_T typedef unsigned short in_port_t; #endif #ifndef HAVE_IN_ADDR_T typedef unsigned int in_addr_t; #endif #define VERSION_LENGTH 128 /*#define SESSION /* * Keep one command connection open to clamd, otherwise a new * command connection is created for each new email * * FIXME: When SESSIONS are open, freshclam can hang when * notfying clamd of an update. This is most likely to be a * problem with the implementation of SESSIONS on clamd. * The problem seems worst on BSD. * * Note that clamd is buggy and can hang or even crash if you * send SESSION command so be aware */ /* * TODO: optional: xmessage on console when virus stopped (SNMP would be real nice!) * Having said that, with LogSysLog you can (on Linux) configure the system * to get messages on the system console, see syslog.conf(5), also you * can use wall(1) in the VirusEvent entry in clamd.conf * TODO: build with libclamav.so rather than libclamav.a * TODO: Warn if TCPAddr doesn't allow connection from us * TODO: Decide action (bounce, discard, reject etc.) based on the virus * found. Those with faked addresses, such as SCO.A want discarding, * others could be bounced properly. * TODO: Encrypt mails sent to clamd to stop sniffers * TODO: Test with IPv6 * TODO: Files can be scanned with "SCAN" not "STREAM" if clamd is on the same * machine when talking via INET domain socket. * TODO: Load balancing, allow local machine to talk via UNIX domain socket. */ struct header_node_t { char *header; struct header_node_t *next; }; struct header_list_struct { struct header_node_t *first; struct header_node_t *last; }; typedef struct header_list_struct *header_list_t; /* * Local addresses are those not scanned if --local is not set * 127.0.0.0 is not in this table since that's goverend by --outgoing * Andy Fiddaman added 69.254.0.0/16 * (Microsoft default DHCP) * * TODO: read this table in from a file (clamd.conf?) */ #define PACKADDR(a, b, c, d) (((uint32_t)(a) << 24) | ((b) << 16) | ((c) << 8) | (d)) #define MAKEMASK(bits) ((uint32_t)(0xffffffff << (bits))) static const struct cidr_net { uint32_t base; uint32_t mask; } localNets[] = { /*{ PACKADDR(127, 0, 0, 0), MAKEMASK(24) }, /* 127.0.0.0/24 */ { PACKADDR(192, 168, 0, 0), MAKEMASK(16) }, /* 192.168.0.0/16 */ { PACKADDR( 10, 0, 0, 0), MAKEMASK(24) }, /* 10.0.0.0/24 */ { PACKADDR(172, 16, 0, 0), MAKEMASK(20) }, /* 172.16.0.0/20 */ { PACKADDR(169, 254, 0, 0), MAKEMASK(16) }, /* 169.254.0.0/16 */ { 0, 0 } }; /* * Each thread has one of these */ struct privdata { char *from; /* Who sent the message */ char *subject; /* Original subject */ char *sender; /* Secretary - often used in mailing lists */ char *helo; /* The HELO string */ char **to; /* Who is the message going to */ int numTo; /* Number of people the message is going to */ #ifndef SESSION int cmdSocket; /* * Socket to send/get commands e.g. PORT for * dataSocket */ #endif int dataSocket; /* Socket to send data to clamd */ char *filename; /* Where to store the message in quarantine */ u_char *body; /* body of the message if Sflag is set */ size_t bodyLen; /* number of bytes in body */ header_list_t headers; /* Message headers */ long numBytes; /* Number of bytes sent so far */ char *received; /* keep track of received from */ const char *rejectCode; /* 550 or 554? */ char *messageID; /* sendmailID */ int discard; /* * looks like the remote end is playing ping * pong with us */ int statusCount; /* number of X-Virus-Status headers */ int serverNumber; /* Index into serverIPs */ }; #ifdef SESSION static int createSession(unsigned int s); #else static int pingServer(int serverNumber); #endif static int findServer(void); static sfsistat clamfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr); #ifdef CL_DEBUG static sfsistat clamfi_helo(SMFICTX *ctx, char *helostring); #endif static sfsistat clamfi_envfrom(SMFICTX *ctx, char **argv); static sfsistat clamfi_envrcpt(SMFICTX *ctx, char **argv); static sfsistat clamfi_header(SMFICTX *ctx, char *headerf, char *headerv); static sfsistat clamfi_eoh(SMFICTX *ctx); static sfsistat clamfi_body(SMFICTX *ctx, u_char *bodyp, size_t len); static sfsistat clamfi_eom(SMFICTX *ctx); static sfsistat clamfi_abort(SMFICTX *ctx); static sfsistat clamfi_close(SMFICTX *ctx); static void clamfi_cleanup(SMFICTX *ctx); static void clamfi_free(struct privdata *privdata); static int clamfi_send(struct privdata *privdata, size_t len, const char *format, ...); static int clamd_recv(int sock, char *buf, size_t len); static off_t updateSigFile(void); static header_list_t header_list_new(void); static void header_list_free(header_list_t list); static void header_list_add(header_list_t list, const char *headerf, const char *headerv); static void header_list_print(header_list_t list, FILE *fp); static int connect2clamd(struct privdata *privdata); static int sendToFrom(struct privdata *privdata); static void checkClamd(void); static int sendtemplate(SMFICTX *ctx, const char *filename, FILE *sendmail, const char *virusname); static int qfile(struct privdata *privdata, const char *sendmailId, const char *virusname); static int move(const char *oldfile, const char *newfile); static void setsubject(SMFICTX *ctx, const char *virusname); static int clamfi_gethostbyname(const char *hostname, struct hostent *hp, char *buf, size_t len); static int isLocalAddr(in_addr_t addr); static void clamdIsDown(void); static void *watchdog(void *a); static int logg_facility(const char *name); static void quit(void); static void broadcast(const char *mess); static int loadDatabase(void); #ifdef SESSION static pthread_mutex_t version_mutex = PTHREAD_MUTEX_INITIALIZER; static char **clamav_versions; /* max_children elements in the array */ #define clamav_version (clamav_versions[0]) #else static char clamav_version[VERSION_LENGTH + 1]; #endif static int fflag = 0; /* force a scan, whatever */ static int oflag = 0; /* scan messages from our machine? */ static int lflag = 0; /* scan messages from our site? */ /* Variables for --external */ static int external = 0; /* scan messages ourself or use clamd? */ static struct cl_node *root = NULL; static struct cl_limits limits; static struct cl_stat dbstat; static int options = CL_SCAN_STDOPT; static int bflag = 0; /* * send a failure (bounce) message to the * sender. This probably isn't a good idea * since most reply addresses will be fake * * TODO: Perhaps we can have an option to * bounce outgoing mail, but not incoming? */ static const char *iface; /* * Broadcast a message when a virus is found, * this allows remote network management */ static int broadcastSock = -1; static int pflag = 0; /* * Send a warning to the postmaster only, * this means user's won't be told when someone * sent them a virus */ static int qflag = 0; /* * Send no warnings when a virus is found, * this means that the only log of viruses * found is the syslog, so it's best to * enable LogSyslog in clamd.conf */ static int Sflag = 0; /* * Add a signature to each message that * has been scanned */ static const char *sigFilename; /* * File where the scanned message signature * can be found */ static char *quarantine; /* * If a virus is found in an email redirect * it to this account */ static char *quarantine_dir; /* * Path to store messages before scanning. * Infected ones will be left there. */ static int nflag = 0; /* * Don't add X-Virus-Scanned to header. Patch * from Dirk Meyer */ static int rejectmail = 1; /* * Send a 550 rejection when a virus is * found */ static int hflag = 0; /* * Include original message headers in * report */ static int cl_error = SMFIS_TEMPFAIL; /* * If an error occurs, return * this status. Allows messages * to be passed through * unscanned in the event of * an error. Patch from * Joe Talbott */ static int readTimeout = CL_DEFAULT_SCANTIMEOUT; /* * number of seconds to wait for clamd to * respond, see ReadTimeout in clamd.conf */ static long streamMaxLength = -1; /* StreamMaxLength from clamd.conf */ static int logClean = 1; /* * Add clean items to the log file */ static char *signature = N_("-- \nScanned by ClamAv - http://www.clamav.net\n"); static time_t signatureStamp; static char *templatefile; /* e-mail to be sent when virus detected */ static const char *tmpdir; #ifdef CL_DEBUG static int debug_level = 0; #endif static pthread_mutex_t n_children_mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t n_children_cond = PTHREAD_COND_INITIALIZER; static volatile unsigned int n_children = 0; static unsigned int max_children = 0; static pthread_mutex_t accept_mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t accept_cond = PTHREAD_COND_INITIALIZER; static volatile int accept_inputs; static int child_timeout = 0; /* number of seconds to wait for * a child to die. Set to 0 to * wait forever */ static int dont_wait = 0; /* * If 1 send retry later to the remote end * if max_chilren is exceeded, otherwise we * wait for the number to go down */ static int advisory = 0; /* * Run clamav-milter in advisory mode - viruses * are flagged rather than deleted. Incompatible * with quarantine options */ static int detect_forged_local_address; /* * for incoming only mail servers, drop emails * claiming to be from us that must be false * Requires that -o, -l or -f are NOT given */ static short use_syslog = 0; static const char *pidFile; static int logVerbose = 0; static struct cfgstruct *copt; static const char *localSocket; /* milter->clamd comms */ static in_port_t tcpSocket; /* milter->clamd comms */ static char *port = NULL; /* sendmail->milter comms */ static const char *serverHostNames = "127.0.0.1"; static long *serverIPs; /* IPv4 only */ static int numServers; /* number of elements in serverIPs array */ #ifdef SESSION static struct session { int sock; /* fd */ enum { CMDSOCKET_FREE, CMDSOCKET_INUSE, CMDSOCKET_DOWN } status; } *sessions; /* max_children elements in the array */ static pthread_mutex_t sstatus_mutex = PTHREAD_MUTEX_INITIALIZER; #endif /*SESSION*/ static pthread_cond_t watchdog_cond = PTHREAD_COND_INITIALIZER; #ifndef SHUT_RD #define SHUT_RD 0 #endif #ifndef SHUT_WR #define SHUT_WR 1 #endif #ifndef INET_ADDRSTRLEN #define INET_ADDRSTRLEN 16 #endif static const char *postmaster = "postmaster"; static const char *from = "MAILER-DAEMON"; static int quitting; static const char *whitelistFile; /* * file containing destination email * addresses that we don't scan */ static const char *sendmailCF; /* location of sendmail.cf to verify */ static const char *pidfile; #ifdef CL_DEBUG #if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 #define HAVE_BACKTRACE #endif #endif static void sigsegv(int sig); #ifdef HAVE_BACKTRACE #include static void print_trace(void); #define BACKTRACE_SIZE 200 #endif static int verifyIncomingSocketName(const char *sockName); static int isWhitelisted(const char *emailaddress); static void logger(const char *mess); static void help(void) { printf("\n\tclamav-milter version %s\n", CM_VERSION); puts("\tCopyright (C) 2004 Nigel Horne \n"); puts(_("\t--advisory\t\t-A\tFlag viruses rather than deleting them.")); puts(_("\t--bounce\t\t-b\tSend a failure message to the sender.")); puts(_("\t--broadcast\t\t-B [IFACE]\tBroadcast to a network manager when a virus is found.")); puts(_("\t--config-file=FILE\t-c FILE\tRead configuration from FILE.")); puts(_("\t--debug\t\t\t-D\tPrint debug messages.")); puts(_("\t--detect-forged-local-address\t-L\tReject mails that claim to be from us.")); puts(_("\t--dont-log-clean\t-C\tDon't add an entry to syslog that a mail is clean.")); puts(_("\t--dont-scan-on-error\t-d\tPass e-mails through unscanned if a system error occurs.")); puts(_("\t--dont-wait\t\t\tAsk remote end to resend if max-children exceeded.")); puts(_("\t--external\t\t-e\tUse an external scanner (usually clamd).")); puts(_("\t--from=EMAIL\t\t-a EMAIL\tError messages come from here.")); puts(_("\t--force-scan\t\t-f\tForce scan all messages (overrides (-o and -l).")); puts(_("\t--help\t\t\t-h\tThis message.")); puts(_("\t--headers\t\t-H\tInclude original message headers in the report.")); puts(_("\t--local\t\t\t-l\tScan messages sent from machines on our LAN.")); puts(_("\t--max-childen\t\t-m\tMaximum number of concurrent scans.")); puts(_("\t--outgoing\t\t-o\tScan outgoing messages from this machine.")); puts(_("\t--noreject\t\t-N\tDon't reject viruses, silently throw them away.")); puts(_("\t--noxheader\t\t-n\tSuppress X-Virus-Scanned/X-Virus-Status headers.")); puts(_("\t--pidfile=FILE\t\t-i FILE\tLocation of pidfile.")); puts(_("\t--postmaster\t\t-p EMAIL\tPostmaster address [default=postmaster].")); puts(_("\t--postmaster-only\t-P\tSend warnings only to the postmaster.")); puts(_("\t--quiet\t\t\t-q\tDon't send e-mail notifications of interceptions.")); puts(_("\t--quarantine=USER\t-Q EMAIL\tQuanrantine e-mail account.")); puts(_("\t--quarantine-dir=DIR\t-U DIR\tDirectory to store infected emails.")); puts(_("\t--server=SERVER\t\t-s SERVER\tHostname/IP address of server(s) running clamd (when using TCPsocket).")); puts(_("\t--sendmail-cf=FILE\t\tLocation of the sendmail.cf file to verify")); puts(_("\t--sign\t\t\t-S\tAdd a hard-coded signature to each scanned message.")); puts(_("\t--signature-file=FILE\t-F FILE\tLocation of signature file.")); puts(_("\t--template-file=FILE\t-t FILE\tLocation of e-mail template file.")); puts(_("\t--timeout=SECS\t\t-T SECS\tTimeout waiting to childen to die.")); puts(_("\t--whitelist-file=FILE\t-W FILE\tLocation of the file of whitelisted addresses")); puts(_("\t--version\t\t-V\tPrint the version number of this software.")); #ifdef CL_DEBUG puts(_("\t--debug-level=n\t\t-x n\tSets the debug level to 'n'.")); #endif puts(_("\nFor more information type \"man clamav-milter\".")); puts(_("Report bugs to bugs@clamav.net.")); } int main(int argc, char **argv) { extern char *optarg; int i, Bflag = 0; const char *cfgfile = CL_DEFAULT_CFG; const struct cfgstruct *cpt; char version[VERSION_LENGTH + 1]; pthread_t tid; #ifndef CL_DEBUG int consolefd; #endif struct smfiDesc smfilter = { "ClamAv", /* filter name */ SMFI_VERSION, /* version code -- leave untouched */ SMFIF_ADDHDRS|SMFIF_CHGHDRS, /* flags - we add and deleted headers */ clamfi_connect, /* connection callback */ #ifdef CL_DEBUG clamfi_helo, /* HELO filter callback */ #else NULL, #endif clamfi_envfrom, /* envelope sender filter callback */ clamfi_envrcpt, /* envelope recipient filter callback */ clamfi_header, /* header filter callback */ clamfi_eoh, /* end of header callback */ clamfi_body, /* body filter callback */ clamfi_eom, /* end of message callback */ clamfi_abort, /* message aborted callback */ clamfi_close, /* connection cleanup callback */ }; #if defined(CL_DEBUG) && defined(C_LINUX) struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY; if(setrlimit(RLIMIT_CORE, &rlim) < 0) perror("setrlimit"); #endif /* * Temporarily enter guessed value into version, will * be overwritten later by the value returned by clamd */ snprintf(version, sizeof(version) - 1, "ClamAV version %s, clamav-milter version %s", VERSION, CM_VERSION); #ifdef C_LINUX setlocale(LC_ALL, ""); bindtextdomain("clamav-milter", DATADIR"/clamav-milter/locale"); textdomain("clamav-milter"); #endif for(;;) { int opt_index = 0; #ifdef CL_DEBUG const char *args = "a:AbB:c:CdDefF:lLm:nNop:PqQ:hHs:St:T:U:VwW:x:0:"; #else const char *args = "a:AbB:c:CdDefF:lLm:nNop:PqQ:hHs:St:T:U:VwW:0:"; #endif static struct option long_options[] = { { "from", 2, NULL, 'a' }, { "advisory", 0, NULL, 'A' }, { "bounce", 0, NULL, 'b' }, { "broadcast", 2, NULL, 'B' }, { "config-file", 1, NULL, 'c' }, { "detect-forged-local-address", 0, NULL, 'L' }, { "dont-log-clean", 0, NULL, 'C' }, { "dont-scan-on-error", 0, NULL, 'd' }, { "dont-wait", 0, NULL, 'w' }, { "debug", 0, NULL, 'D' }, { "external", 0, NULL, 'e' }, { "force-scan", 0, NULL, 'f' }, { "headers", 0, NULL, 'H' }, { "help", 0, NULL, 'h' }, { "pidfile", 1, NULL, 'i' }, { "local", 0, NULL, 'l' }, { "noreject", 0, NULL, 'N' }, { "noxheader", 0, NULL, 'n' }, { "outgoing", 0, NULL, 'o' }, { "postmaster", 1, NULL, 'p' }, { "postmaster-only", 0, NULL, 'P', }, { "quiet", 0, NULL, 'q' }, { "quarantine", 1, NULL, 'Q', }, { "quarantine-dir", 1, NULL, 'U', }, { "max-children", 1, NULL, 'm' }, { "server", 1, NULL, 's' }, { "sign", 0, NULL, 'S' }, { "signature-file", 1, NULL, 'F' }, { "template-file", 1, NULL, 't' }, { "timeout", 1, NULL, 'T' }, { "whitelist-file", 1, NULL, 'W' }, { "version", 0, NULL, 'V' }, { "sendmail-cf", 1, NULL, '0' }, #ifdef CL_DEBUG { "debug-level", 1, NULL, 'x' }, #endif { NULL, 0, NULL, '\0' } }; int ret = getopt_long(argc, argv, args, long_options, &opt_index); if(ret == -1) break; else if(ret == 0) ret = long_options[opt_index].val; switch(ret) { case 'a': /* e-mail errors from here */ /* * optarg is optional - if you give --from * then the --from is set to the orginal, * probably forged, email address */ from = optarg; break; case 'A': advisory++; break; case 'b': /* bounce worms/viruses */ bflag++; break; case 'B': /* broadcast */ Bflag++; if(optarg) iface = optarg; break; case 'c': /* where is clamd.conf? */ cfgfile = optarg; break; case 'C': /* dont log clean */ logClean = 0; break; case 'd': /* don't scan on error */ cl_error = SMFIS_ACCEPT; break; case 'D': /* enable debug messages */ cl_debug(); break; case 'e': /* use clamd */ external++; break; case 'f': /* force the scan */ fflag++; break; case 'h': help(); return EX_OK; case 'H': hflag++; break; case 'i': /* pidfile */ pidfile = optarg; break; case 'l': /* scan mail from the lan */ lflag++; break; case 'L': /* detect forged local addresses */ detect_forged_local_address++; break; case 'm': /* maximum number of children */ max_children = atoi(optarg); break; case 'n': /* don't add X-Virus-Scanned */ nflag++; smfilter.xxfi_flags &= ~(SMFIF_ADDHDRS|SMFIF_CHGHDRS); break; case 'N': /* Do we reject mail or silently drop it */ rejectmail = 0; break; case 'o': /* scan outgoing mail */ oflag++; break; case 'p': /* postmaster e-mail address */ postmaster = optarg; break; case 'P': /* postmaster only */ pflag++; break; case 'q': /* send NO notification email */ qflag++; break; case 'Q': /* quarantine e-mail address */ quarantine = optarg; smfilter.xxfi_flags |= SMFIF_CHGHDRS|SMFIF_ADDRCPT|SMFIF_DELRCPT; break; case 's': /* server running clamd */ #ifdef notdef /* don't define - forces --external to be listed first :-( */ if(!external) { fputs("--server can only be used with --external\n", stderr); return EX_USAGE; } #endif serverHostNames = optarg; break; case 'F': /* signature file */ sigFilename = optarg; signature = NULL; /* fall through */ case 'S': /* sign */ smfilter.xxfi_flags |= SMFIF_CHGBODY; Sflag++; break; case 't': /* e-mail template file */ templatefile = optarg; break; case 'T': /* time to wait for child to die */ child_timeout = atoi(optarg); break; case 'U': /* quarantine path */ quarantine_dir = optarg; break; case 'V': puts(version); return EX_OK; case 'w': dont_wait++; break; case 'W': whitelistFile = optarg; break; case '0': sendmailCF = optarg; break; #ifdef CL_DEBUG case 'x': debug_level = atoi(optarg); break; #endif default: #ifdef CL_DEBUG fprintf(stderr, "Usage: %s [-b] [-c FILE] [-F FILE] [--max-children=num] [-e] [-l] [-o] [-p address] [-P] [-q] [-Q USER] [-s SERVER] [-S] [-x#] [-U PATH] socket-addr\n", argv[0]); #else fprintf(stderr, "Usage: %s [-b] [-c FILE] [-F FILE] [--max-children=num] [-e] [-l] [-o] [-p address] [-P] [-q] [-Q USER] [-s SERVER] [-S] [-U PATH] socket-addr\n", argv[0]); #endif return EX_USAGE; } } /* FIXME: error if --servers and --external is not given */ /* TODO: support freshclam's daemon notify if --external is not given */ if(optind == argc) { fprintf(stderr, _("%s: No socket-addr given\n"), argv[0]); return EX_USAGE; } port = argv[optind]; if(verifyIncomingSocketName(port) < 0) { fprintf(stderr, _("%s: socket-addr (%s) doesn't agree with sendmail.cf\n"), argv[0], port); return EX_CONFIG; } if(strncasecmp(port, "inet:", 5) == 0) if(!lflag) { /* * Barmy but true. It seems that clamfi_connect will, * in this case, get the IP address of the machine * running sendmail, not of the machine sending the * mail, so the remote end will be a local address so * we must scan by enabling --local * * TODO: this is probably not needed if the remote * machine is localhost, need to check though */ fprintf(stderr, _("%s: when using inet: connection to sendmail you must enable --local\n"), argv[0]); return EX_USAGE; } /* * Sanity checks on the clamav configuration file */ if((copt = parsecfg(cfgfile, 1)) == NULL) { fprintf(stderr, _("%s: Can't parse the config file %s\n"), argv[0], cfgfile); return EX_CONFIG; } if(detect_forged_local_address) { if(oflag) { fprintf(stderr, _("%s: --detect-forged-local-addresses is not compatible with --outgoing\n"), argv[0]); return EX_CONFIG; } if(lflag) { fprintf(stderr, _("%s: --detect-forged-local-addresses is not compatible with --local\n"), argv[0]); return EX_CONFIG; } if(fflag) { fprintf(stderr, _("%s: --detect-forged-local-addresses is not compatible with --force\n"), argv[0]); return EX_CONFIG; } } if(Bflag) { int on; broadcastSock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); /* * SO_BROADCAST doesn't sent to all NICs on Linux, it only * broadcasts on eth0, which is why there's an optional argument * to --broadcast to say which NIC to broadcast on. You can use * SO_BINDTODEVICE to get around that, but you need to have * uid == 0 for that */ on = 1; if(setsockopt(broadcastSock, SOL_SOCKET, SO_BROADCAST, (int *)&on, sizeof(on)) < 0) { perror("setsockopt"); return EX_UNAVAILABLE; } shutdown(broadcastSock, SHUT_RD); } /* * Drop privileges */ #ifndef CL_DEBUG /* Save the fd for later, open while we can */ consolefd = open(console, O_WRONLY); #endif if(getuid() == 0) { if(iface) { #ifdef SO_BINDTODEVICE struct ifreq ifr; memset(&ifr, '\0', sizeof(struct ifreq)); strncpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1); if(setsockopt(broadcastSock, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)) < 0) { perror(iface); return EX_CONFIG; } #else fprintf(stderr, _("%s: The iface option to --broadcast is not supported on your operating system\n"), argv[0]); return EX_CONFIG; #endif } if((cpt = cfgopt(copt, "User")) != NULL) { const struct passwd *user; if((user = getpwnam(cpt->strarg)) == NULL) { fprintf(stderr, _("%s: Can't get information about user %s\n"), argv[0], cpt->strarg); return EX_CONFIG; } if(cfgopt(copt, "AllowSupplementaryGroups")) { #ifdef HAVE_INITGROUPS if(initgroups(cpt->strarg, user->pw_gid) < 0) { perror(cpt->strarg); return EX_CONFIG; } #else fprintf(stderr, _("%s: AllowSupplementaryGroups: initgroups not supported.\n"), argv[0]); return EX_CONFIG; #endif } else { #ifdef HAVE_SETGROUPS if(setgroups(1, &user->pw_gid) < 0) { perror(cpt->strarg); return EX_CONFIG; } #endif } setgid(user->pw_gid); if(setuid(user->pw_uid) < 0) perror(cpt->strarg); else cli_dbgmsg(_("Running as user %s (UID %d, GID %d)\n"), cpt->strarg, user->pw_uid, user->pw_gid); } else fprintf(stderr, _("%s: running as root is not recommended (check \"User\" in clamd.conf)\n"), argv[0]); } else if(iface) { fprintf(stderr, _("%s: Only root can set an interface for --broadcast\n"), argv[0]); return EX_USAGE; } if(advisory && quarantine) { fprintf(stderr, _("%s: Advisory mode doesn't work with quarantine mode\n"), argv[0]); return EX_USAGE; } if(quarantine_dir) { struct stat statb; if(advisory) { fprintf(stderr, _("%s: Advisory mode doesn't work with quarantine directories\n"), argv[0]); return EX_USAGE; } if(strstr(quarantine_dir, "ERROR") != NULL) { fprintf(stderr, _("%s: the quarantine directory must not contain the string 'ERROR'\n"), argv[0]); return EX_USAGE; } if(strstr(quarantine_dir, "FOUND") != NULL) { fprintf(stderr, _("%s: the quarantine directory must not contain the string 'FOUND'\n"), argv[0]); return EX_USAGE; } if(strstr(quarantine_dir, "OK") != NULL) { fprintf(stderr, _("%s: the quarantine directory must not contain the string 'OK'\n"), argv[0]); return EX_USAGE; } if(access(quarantine_dir, W_OK) < 0) { perror(quarantine_dir); return EX_USAGE; } if(stat(quarantine_dir, &statb) < 0) { perror(quarantine_dir); return EX_USAGE; } /* * Quit if the quarantine directory is publically readable * or writeable */ if(statb.st_mode & 077) { fprintf(stderr, _("%s: insecure quarantine directory %s (mode 0%o)\n"), argv[0], quarantine_dir, statb.st_mode & 0777); return EX_CONFIG; } } if(sigFilename && !updateSigFile()) return EX_USAGE; if(templatefile && (access(templatefile, R_OK) < 0)) { perror(templatefile); return EX_CONFIG; } /* * patch from "Richard G. Roberto" * If the --max-children flag isn't set, see if MaxThreads * is set in the config file */ if((max_children == 0) && ((cpt = cfgopt(copt, "MaxThreads")) != NULL)) max_children = cpt->numarg; if((cpt = cfgopt(copt, "ReadTimeout")) != NULL) { readTimeout = cpt->numarg; if(readTimeout < 0) { fprintf(stderr, _("%s: ReadTimeout must not be negative in %s\n"), argv[0], cfgfile); return EX_CONFIG; } } if((cpt = cfgopt(copt, "StreamMaxLength")) != NULL) { if(cpt->numarg < 0) { fprintf(stderr, _("%s: StreamMaxLength must not be negative in %s\n"), argv[0], cfgfile); return EX_CONFIG; } streamMaxLength = (long)cpt->numarg; } if(cfgopt(copt, "LogSyslog")) { int fac = LOG_LOCAL6; if(cfgopt(copt, "LogVerbose")) { logVerbose = 1; #if 0 /* Only supported by Sendmail >= V8.13 */ smfi_setdbg(6); #endif } use_syslog = 1; if((cpt = cfgopt(copt, "LogFacility")) != NULL) if((fac = logg_facility(cpt->strarg)) == -1) { fprintf(stderr, "%s: LogFacility: %s: No such facility\n", argv[0], cpt->strarg); return EX_CONFIG; } openlog("clamav-milter", LOG_CONS|LOG_PID, fac); } else { if(qflag) fprintf(stderr, _("%s: (-q && !LogSyslog): warning - all interception message methods are off\n"), argv[0]); use_syslog = 0; } /* * Get the outgoing socket details - the way to talk to clamd, unless * we're doing the scanning internally */ if(!external) { if(max_children == 0) { fprintf(stderr, _("%s: --max-children must be given if --external is not given\n"), argv[0]); return EX_CONFIG; } if(child_timeout) { fprintf(stderr, _("%s: --timeout must not be given if --external is not given\n"), argv[0]); return EX_CONFIG; } if(loadDatabase() != 0) return EX_CONFIG; numServers = 1; } else if((cpt = cfgopt(copt, "LocalSocket")) != NULL) { #ifdef SESSION struct sockaddr_un server; #endif char *sockname = NULL; if(cfgopt(copt, "TCPSocket") != NULL) { fprintf(stderr, _("%s: You can select one server type only (local/TCP) in %s\n"), argv[0], cfgfile); return EX_CONFIG; } if(strncasecmp(port, "unix:", 5) == 0) sockname = &port[5]; else if(strncasecmp(port, "local:", 6) == 0) sockname = &port[6]; if(sockname && (strcmp(sockname, cpt->strarg) == 0)) { fprintf(stderr, _("The connection from sendmail to %s (%s) must not\n"), argv[0], sockname); fprintf(stderr, _("be the same as the connection to clamd (%s) in %s\n"), cpt->strarg, cfgfile); return EX_CONFIG; } /* * TODO: check --server hasn't been set */ localSocket = cpt->strarg; #ifndef SESSION if(!pingServer(-1)) { fprintf(stderr, _("Can't talk to clamd server via %s\n"), localSocket); fprintf(stderr, _("Check your entry for LocalSocket in %s\n"), cfgfile); return EX_CONFIG; } #endif /*if(quarantine_dir == NULL) fprintf(stderr, _("When using Localsocket in %s\nyou may improve performance if you use the --quarantine-dir option\n"), cfgfile);*/ umask(077); serverIPs = (long *)cli_malloc(sizeof(long)); serverIPs[0] = inet_addr("127.0.0.1"); #ifdef SESSION memset((char *)&server, 0, sizeof(struct sockaddr_un)); server.sun_family = AF_UNIX; strncpy(server.sun_path, localSocket, sizeof(server.sun_path)); sessions = (struct session *)cli_malloc(sizeof(struct session)); if((sessions[0].sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { perror(localSocket); fprintf(stderr, _("Can't talk to clamd server via %s\n"), localSocket); fprintf(stderr, _("Check your entry for LocalSocket in %s\n"), cfgfile); return EX_CONFIG; } if(connect(sessions[0].sock, (struct sockaddr *)&server, sizeof(struct sockaddr_un)) < 0) { perror(localSocket); return EX_UNAVAILABLE; } if(send(sessions[0].sock, "SESSION\n", 7, 0) < 7) { perror("send"); if(use_syslog) syslog(LOG_ERR, _("Can't create a clamd session")); return EX_UNAVAILABLE; } sessions[0].status = CMDSOCKET_FREE; #endif /* * FIXME: Allow connection to remote servers by TCP/IP whilst * connecting to the localserver via a UNIX domain socket */ numServers = 1; } else if((cpt = cfgopt(copt, "TCPSocket")) != NULL) { int activeServers; /* * TCPSocket is in fact a port number not a full socket */ if(quarantine_dir) { fprintf(stderr, _("%s: --quarantine-dir not supported for TCPSocket - use --quarantine\n"), argv[0]); return EX_CONFIG; } tcpSocket = (in_port_t)cpt->numarg; /* * cli_strtok's fieldno counts from 0 */ for(;;) { char *hostname = cli_strtok(serverHostNames, numServers, ":"); if(hostname == NULL) break; #ifdef MAXHOSTNAMELEN if(strlen(hostname) > MAXHOSTNAMELEN) { fprintf(stderr, _("%s: hostname %s is longer than %d characters\n"), argv[0], hostname, MAXHOSTNAMELEN); return EX_CONFIG; } #endif numServers++; free(hostname); } cli_dbgmsg("numServers: %d\n", numServers); serverIPs = (long *)cli_malloc(numServers * sizeof(long)); activeServers = 0; #ifdef SESSION /* * We need to know how many connections to establish to clamd */ if(max_children == 0) { fprintf(stderr, _("%s: --max-children must be given in sessions mode\n"), argv[0]); return EX_CONFIG; } #endif for(i = 0; i < numServers; i++) { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; if(cli_strtokbuf(serverHostNames, i, ":", hostname) == NULL) break; #else char *hostname = cli_strtok(serverHostNames, i, ":"); #endif /* * Translate server's name to IP address */ serverIPs[i] = inet_addr(hostname); if(serverIPs[i] == -1L) { const struct hostent *h = gethostbyname(hostname); if(h == NULL) { fprintf(stderr, _("%s: Unknown host %s\n"), argv[0], hostname); return EX_USAGE; } memcpy((char *)&serverIPs[i], h->h_addr, sizeof(serverIPs[i])); } #ifndef SESSION if(pingServer(i)) activeServers++; else { cli_warnmsg(_("Can't talk to clamd server %s on port %d\n"), hostname, tcpSocket); } #endif #ifndef MAXHOSTNAMELEN free(hostname); #endif } #ifdef SESSION activeServers = numServers; sessions = (struct session *)cli_calloc(max_children, sizeof(struct session)); for(i = 0; i < (int)max_children; i++) if(createSession(i) < 0) return EX_UNAVAILABLE; if(activeServers == 0) { cli_warnmsg(_("Can't find any active clamd servers\n")); cli_warnmsg(_("Check your entry for TCPSocket in %s\n"), cfgfile); } #else if(activeServers == 0) { cli_errmsg(_("Can't find any clamd servers\n")); cli_errmsg(_("Check your entry for TCPSocket in %s\n"), cfgfile); return EX_CONFIG; } #endif } else { fprintf(stderr, _("%s: You must select server type (local/TCP) in %s\n"), argv[0], cfgfile); return EX_CONFIG; } #ifdef SESSION if(!external) { if(clamav_versions == NULL) { clamav_versions = (char **)cli_malloc(sizeof(char *)); if(clamav_versions == NULL) return EX_TEMPFAIL; clamav_version = strdup(version); } } else { unsigned int session; /* * We need to know how many connections to establish to clamd */ if(max_children == 0) { fprintf(stderr, _("%s: --max-children must be given in sessions mode\n"), argv[0]); return EX_CONFIG; } clamav_versions = (char **)cli_malloc(max_children * sizeof(char *)); if(clamav_versions == NULL) return EX_TEMPFAIL; for(session = 0; session < max_children; session++) { clamav_versions[session] = strdup(version); if(clamav_versions[session] == NULL) return EX_TEMPFAIL; } } #else strcpy(clamav_version, version); #endif if(((quarantine_dir == NULL) && localSocket) || !external) { /* set the temporary dir */ if((cpt = cfgopt(copt, "TemporaryDirectory"))) { tmpdir = cpt->strarg; cl_settempdir(tmpdir, (short)(cfgopt(copt, "LeaveTemporaryFiles") != NULL)); } else if((tmpdir = getenv("TMPDIR")) == (char *)NULL) if((tmpdir = getenv("TMP")) == (char *)NULL) if((tmpdir = getenv("TEMP")) == (char *)NULL) #ifdef P_tmpdir tmpdir = P_tmpdir; #else tmpdir = "/tmp"; #endif /* * TODO: investigate mkdtemp on LINUX and possibly others */ tmpdir = cli_gentemp(NULL); cli_dbgmsg("Making %s\n", tmpdir); if(mkdir(tmpdir, 0700)) { perror(tmpdir); return EX_CANTCREAT; } } else tmpdir = NULL; if(!cfgopt(copt, "Foreground")) { #ifdef CL_DEBUG printf(_("When debugging it is recommended that you use Foreground mode in %s\n"), cfgfile); puts(_("\tso that you can see all of the messages")); #endif switch(fork()) { case -1: perror("fork"); return EX_OSERR; case 0: /* child */ break; default: /* parent */ return EX_OK; } close(0); open("/dev/null", O_RDONLY); #ifndef CL_DEBUG close(1); if((cpt = cfgopt(copt, "LogFile"))) { logFile = cpt->strarg; #if defined(MSDOS) || defined(C_CYGWIN) || defined(WIN32) if((strlen(logFile) < 2) || ((logFile[0] != '/') && (logFile[0] != '\\') && (logFile[1] != ':'))) { #else if((strlen(logFile) < 2) || (logFile[0] != '/')) { #endif fprintf(stderr, "%s: LogFile requires full path\n", argv[0]); return EX_CONFIG; } if(open(logFile, O_WRONLY|O_APPEND) < 0) { perror(logFile); return EX_CANTCREAT; } } else { logFile = console; if(consolefd < 0) { perror(console); return EX_OSFILE; } dup(consolefd); } close(2); dup(1); if(consolefd >= 0) close(consolefd); if(cfgopt(copt, "LogTime")) logTime++; #endif /*!CL_DEBUG*/ #ifdef HAVE_SETPGRP #ifdef SETPGRP_VOID setpgrp(); #else setpgrp(0,0); #endif #else #ifdef HAVE_SETSID setsid(); #endif #endif } atexit(quit); if(!external) { /* TODO: read the limits from clamd.conf */ if(cfgopt(copt, "DisableDefaultScanOptions")) { options &= ~CL_SCAN_STDOPT; if(!cfgopt(copt, "ScanMail")) printf(_("%s: ScanMail not defined in %s (needed without --external), enabling\n"), argv[0], cfgfile); } options |= CL_SCAN_MAIL; /* no choice */ if(!cfgopt(copt, "ScanRAR")) options |= CL_SCAN_DISABLERAR; if(cfgopt(copt, "ArchiveBlockEncrypted")) options |= CL_SCAN_BLOCKENCRYPTED; if(cfgopt(copt, "ArchiveBlockMax")) options |= CL_SCAN_BLOCKMAX; if(cfgopt(copt, "ScanPE")) options |= CL_SCAN_PE; if(cfgopt(copt, "DetectBrokenExecutables")) options |= CL_SCAN_BLOCKBROKEN; if(cfgopt(copt, "MailFollowURLs")) options |= CL_SCAN_MAILURL; if(cfgopt(copt, "ScanOLE2")) options |= CL_SCAN_OLE2; if(cfgopt(copt, "ScanHTML")) options |= CL_SCAN_HTML; memset(&limits, '\0', sizeof(struct cl_limits)); if(cfgopt(copt, "ScanArchive")) { options |= CL_SCAN_ARCHIVE; if((cpt = cfgopt(copt, "ArchiveMaxFileSize")) != NULL) limits.maxfilesize = cpt->numarg; else limits.maxfilesize = 10485760; if((cpt = cfgopt(copt, "ArchiveMaxRecursion")) != NULL) limits.maxreclevel = cpt->numarg; else limits.maxreclevel = 8; if((cpt = cfgopt(copt, "ArchiveMaxFiles")) != NULL) limits.maxfiles = cpt->numarg; else limits.maxfiles = 1000; if((cpt = cfgopt(copt, "ArchiveMaxCompressionRatio")) != NULL) limits.maxratio = cpt->numarg; else limits.maxratio = 250; if(cfgopt(copt, "ArchiveLimitMemoryUsage") != NULL) limits.archivememlim = 1; else limits.archivememlim = 0; } } accept_inputs = 1; #ifdef SESSION /* FIXME: add localSocket support to watchdog */ if((localSocket == NULL) || external) #endif pthread_create(&tid, NULL, watchdog, NULL); if((cpt = cfgopt(copt, "PidFile")) != NULL) pidFile = cpt->strarg; broadcast(_("Starting clamav-milter")); if(pidfile) { /* save the PID */ char *p, *q; FILE *fd; const mode_t old_umask = umask(0006); if(pidfile[0] != '/') { if(use_syslog) syslog(LOG_ERR, _("pidfile: '%s' must be a full pathname"), pidfile); cli_errmsg(_("pidfile '%s' must be a full pathname\n"), pidfile); return EX_CONFIG; } p = strdup(pidfile); q = strrchr(p, '/'); *q = '\0'; if(chdir(p) < 0) /* safety */ perror(p); free(p); if((fd = fopen(pidfile, "w")) == NULL) { if(use_syslog) syslog(LOG_ERR, _("Can't save PID in file %s"), pidfile); cli_errmsg(_("Can't save PID in file %s\n"), pidfile); return EX_CONFIG; } #ifdef C_LINUX /* Ensure that all threads are kill()ed */ fprintf(fd, "-%d\n", (int)getpgrp()); #else fprintf(fd, "%d\n", (int)getpid()); #endif fclose(fd); umask(old_umask); } else if(tmpdir) chdir(tmpdir); /* safety */ else #ifdef P_tmpdir chdir(P_tmpdir); #else chdir("/tmp"); #endif if(cfgopt(copt, "FixStaleSocket")) { /* * Get the incoming socket details - the way sendmail talks to * us * * TODO: There's a security problem here that'll need fixing if * the User entry of clamd.conf is not used */ if(strncasecmp(port, "unix:", 5) == 0) { if(unlink(&port[5]) < 0) if(errno != ENOENT) perror(&port[5]); } else if(strncasecmp(port, "local:", 6) == 0) { if(unlink(&port[6]) < 0) if(errno != ENOENT) perror(&port[6]); } } if(smfi_setconn(port) == MI_FAILURE) { cli_errmsg("smfi_setconn failure\n"); return EX_SOFTWARE; } if(smfi_register(smfilter) == MI_FAILURE) { cli_errmsg("smfi_register failure\n"); return EX_UNAVAILABLE; } #if 0 /* Only supported by Sendmail >= V8.13 */ if(smfi_opensocket(1) == MI_FAILURE) { cli_errmsg("can't open/create %s\n", port); return EX_CONFIG; } #endif signal(SIGPIPE, SIG_IGN); /* libmilter probably does this as well */ #ifdef SESSION pthread_mutex_lock(&version_mutex); #endif if(use_syslog) { syslog(LOG_INFO, _("Starting %s"), clamav_version); #ifdef CL_DEBUG if(debug_level > 0) syslog(LOG_DEBUG, _("Debugging is on")); #endif } cli_dbgmsg("Started: %s\n", clamav_version); #ifdef SESSION pthread_mutex_unlock(&version_mutex); #endif (void)signal(SIGSEGV, sigsegv); return smfi_main(); } #ifdef SESSION /* * Use the SESSION command of clamd. * Returns -1 for terminal failure, 0 for OK, 1 for nonterminal failure * The caller must take care of locking the sessions array */ static int createSession(unsigned int s) { int ret = 0, fd; struct sockaddr_in server; const int serverNumber = s % numServers; struct session *session = &sessions[s]; cli_dbgmsg("createSession session %d, server %d\n", s, serverNumber); assert(s < max_children); memset((char *)&server, 0, sizeof(struct sockaddr_in)); server.sin_family = AF_INET; server.sin_port = (in_port_t)htons(tcpSocket); server.sin_addr.s_addr = serverIPs[serverNumber]; session->sock = -1; if((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { perror("socket"); ret = -1; } else if(connect(fd, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) < 0) { perror("connect"); ret = 1; } else if(send(fd, "SESSION\n", 7, 0) < 7) { perror("send"); ret = 1; } if(ret != 0) { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; cli_strtokbuf(serverHostNames, serverNumber, ":", hostname); if(strcmp(hostname, "127.0.0.1") == 0) gethostname(hostname, sizeof(hostname)); #else char *hostname = cli_strtok(serverHostNames, serverNumber, ":"); #endif session->status = CMDSOCKET_DOWN; if(fd >= 0) close(fd); cli_warnmsg(_("Check clamd server %s - it may be down\n"), hostname); #ifndef MAXHOSTNAMELEN free(hostname); #endif broadcast(_("Check clamd server - it may be down")); } else session->sock = fd; return ret; } #else /* * Verify that the server is where we think it is * Returns true or false * * serverNumber counts from 0, but is only used for TCPSocket */ static int pingServer(int serverNumber) { char *ptr; int sock, nbytes; char buf[128]; if(localSocket) { struct sockaddr_un server; memset((char *)&server, 0, sizeof(struct sockaddr_un)); server.sun_family = AF_UNIX; strncpy(server.sun_path, localSocket, sizeof(server.sun_path)); if((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { perror(localSocket); return 0; } checkClamd(); if(connect(sock, (struct sockaddr *)&server, sizeof(struct sockaddr_un)) < 0) { perror(localSocket); close(sock); return 0; } } else { struct sockaddr_in server; memset((char *)&server, 0, sizeof(struct sockaddr_in)); server.sin_family = AF_INET; server.sin_port = (in_port_t)htons(tcpSocket); assert(serverIPs != NULL); assert(serverIPs[0] != -1L); server.sin_addr.s_addr = serverIPs[serverNumber]; if((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) { perror("socket"); return 0; } if(connect(sock, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) < 0) { perror("connect"); close(sock); return 0; } } /* * It would be better to use PING, check for PONG then issue the * VERSION command, since that would better validate that we're * talking to clamd, however clamd closes the session after * sending PONG :-( * So this code does not really validate that we're talking to clamd * Needs a fix to clamd * Also version command is verbose: says "clamd / ClamAV version" * instead of "clamAV version" */ cli_dbgmsg("pingServer%d: sending VERSION\n", serverNumber); if(send(sock, "VERSION\n", 8, 0) < 8) { perror("send"); close(sock); return 0; } shutdown(sock, SHUT_WR); nbytes = clamd_recv(sock, buf, sizeof(buf)); close(sock); if(nbytes < 0) { perror("recv"); return 0; } if(nbytes == 0) return 0; buf[nbytes] = '\0'; /* Remove the trailing new line from the reply */ if((ptr = strchr(buf, '\n')) != NULL) *ptr = '\0'; /* * No real validation is done here * * TODO: When connecting to more than one server, give a warning * if they're running different versions, or if the virus DBs * are out of date (say more than a month old) */ snprintf(clamav_version, sizeof(clamav_version) - 1, "%s\n\tclamav-milter version %s", buf, CM_VERSION); return 1; } #endif /* * Find the best server to connect to. No intelligence to this. * It is best to weight the order of the servers from most wanted to least * wanted * * Return value is from 0 - index into sessions array * * If the load balancing fails return the first server in the list, not * an error, to be on the safe side */ #ifdef SESSION static int findServer(void) { unsigned int i, j; struct session *session; /* * FIXME: Sessions code isn't flexible at handling servers * appearing and disappearing, e.g. sessions[n_children].sock == -1 */ i = 0; pthread_mutex_lock(&n_children_mutex); assert(n_children > 0); assert(n_children <= max_children); j = n_children - 1; pthread_mutex_unlock(&n_children_mutex); pthread_mutex_lock(&sstatus_mutex); for(; i < max_children; i++) { const int sess = (j + i) % max_children; session = &sessions[sess]; cli_dbgmsg("findServer: try server %d\n", sess); if(session->status == CMDSOCKET_FREE) { session->status = CMDSOCKET_INUSE; pthread_mutex_unlock(&sstatus_mutex); return sess; } } pthread_mutex_unlock(&sstatus_mutex); /* * No session free - wait until one comes available. Only * retries once. */ if(pthread_cond_broadcast(&watchdog_cond) < 0) perror("pthread_cond_broadcast"); i = 0; session = sessions; pthread_mutex_lock(&sstatus_mutex); for(; i < max_children; i++, session++) { cli_dbgmsg("findServer: try server %d\n", i); if(session->status == CMDSOCKET_FREE) { session->status = CMDSOCKET_INUSE; pthread_mutex_unlock(&sstatus_mutex); return i; } } pthread_mutex_unlock(&sstatus_mutex); cli_warnmsg(_("No free clamd sessions\n")); return -1; /* none available - must fail */ } #else /* * Return value is from 0 - index into serverIPs */ static int findServer(void) { struct sockaddr_in *servers, *server; int *socks, maxsock = 0, i, j; fd_set rfds; struct timeval tv; int retval; assert(tcpSocket != 0); assert(numServers > 0); if(numServers == 1) return 0; servers = (struct sockaddr_in *)cli_calloc(numServers, sizeof(struct sockaddr_in)); socks = (int *)cli_malloc(numServers * sizeof(int)); FD_ZERO(&rfds); if(max_children > 0) { assert(n_children > 0); assert(n_children <= max_children); /* * Don't worry about no lock - it's doesn't matter if it's * not really accurate */ j = n_children - 1; } else /* * cli_rndnum returns 0..(max-1) - the max argument is not * the maximum number you want it to return, it is in fact * one *more* than the maximum number you want it to return */ j = cli_rndnum(numServers); for(i = 0, server = servers; i < numServers; i++, server++) { int sock; server->sin_family = AF_INET; server->sin_port = (in_port_t)htons(tcpSocket); server->sin_addr.s_addr = serverIPs[(i + j) % numServers]; cli_dbgmsg("findServer: try server %d\n", (i + j) % numServers); sock = socks[i] = socket(AF_INET, SOCK_STREAM, 0); if(sock < 0) { perror("socket"); do if(socks[i] >= 0) close(socks[i]); while(--i >= 0); free(socks); free(servers); return 0; /* Use the first server on failure */ } if((connect(sock, (struct sockaddr *)server, sizeof(struct sockaddr)) < 0) || (send(sock, "PING\n", 5, 0) < 5)) { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; cli_strtokbuf(serverHostNames, i, ":", hostname); if(strcmp(hostname, "127.0.0.1") == 0) gethostname(hostname, sizeof(hostname)); #else char *hostname = cli_strtok(serverHostNames, i, ":"); #endif cli_warnmsg(_("Check clamd server %s - it may be down\n"), hostname); if(use_syslog) syslog(LOG_WARNING, _("Check clamd server %s - it may be down"), hostname); close(sock); #ifndef MAXHOSTNAMELEN free(hostname); #endif broadcast(_("Check clamd server - it may be down\n")); socks[i] = -1; continue; } shutdown(sock, SHUT_WR); FD_SET(sock, &rfds); if(sock > maxsock) maxsock = sock; } free(servers); tv.tv_sec = readTimeout; tv.tv_usec = 0; if(maxsock == 0) retval = 0; else retval = select(maxsock + 1, &rfds, NULL, NULL, &tv); if(retval < 0) perror("select"); for(i = 0; i < numServers; i++) if(socks[i] >= 0) close(socks[i]); if(retval == 0) { free(socks); clamdIsDown(); return 0; } else if(retval < 0) { free(socks); if(use_syslog) syslog(LOG_ERR, _("findServer: select failed")); return 0; } for(i = 0; i < numServers; i++) if((socks[i] >= 0) && (FD_ISSET(socks[i], &rfds))) { const int s = (i + j) % numServers; free(socks); cli_dbgmsg(_("findServer: using server %d\n"), s); return s; } free(socks); cli_dbgmsg(_("findServer: No response from any server\n")); if(use_syslog) syslog(LOG_WARNING, _("findServer: No response from any server")); return 0; } #endif /* * Sendmail wants to establish a connection to us */ static sfsistat clamfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr) { #if defined(HAVE_INET_NTOP) || defined(WITH_TCPWRAP) char ip[INET_ADDRSTRLEN]; /* IPv4 only */ #endif const char *remoteIP; int accepting; if(quitting) return cl_error; pthread_mutex_lock(&accept_mutex); accepting = accept_inputs; pthread_mutex_unlock(&accept_mutex); if(!accepting) { #if 1 cli_warnmsg("Not accepting inputs at the moment\n"); /* * We must refuse here even if dont_wait isn't set, since * it could take some time, and sendmail could time us out * and refuse to have anything more to do with us until * the program is restarted */ if(dont_wait) return SMFIS_TEMPFAIL; pthread_mutex_lock(&accept_mutex); while(!accept_inputs) pthread_cond_wait(&accept_cond, &accept_mutex); pthread_mutex_unlock(&accept_mutex); cli_warnmsg("Accepting inputs again\n"); #endif /*return SMFIS_TEMPFAIL;*/ } if(ctx == NULL) { if(use_syslog) syslog(LOG_ERR, _("clamfi_connect: ctx is null")); return cl_error; } if(hostname == NULL) { if(use_syslog) syslog(LOG_ERR, _("clamfi_connect: hostname is null")); return cl_error; } if((hostaddr == NULL) || (&(((struct sockaddr_in *)(hostaddr))->sin_addr) == NULL)) /* * According to the sendmail API hostaddr is NULL if * "the type is not supported in the current version". What * the documentation doesn't say is the type of what. * * Possibly the input is not a TCP/IP socket e.g. stdin? */ remoteIP = "127.0.0.1"; else { #ifdef HAVE_INET_NTOP remoteIP = (char *)inet_ntop(AF_INET, &((struct sockaddr_in *)(hostaddr))->sin_addr, ip, sizeof(ip)); #else remoteIP = inet_ntoa(((struct sockaddr_in *)(hostaddr))->sin_addr); #endif if(remoteIP == NULL) { if(use_syslog) syslog(LOG_ERR, _("clamfi_connect: remoteIP is null")); return cl_error; } } #ifdef CL_DEBUG if(debug_level >= 4) { if(hostname[0] == '[') { if(use_syslog) syslog(LOG_NOTICE, _("clamfi_connect: connection from %s"), remoteIP); cli_dbgmsg(_("clamfi_connect: connection from %s\n"), remoteIP); } else { if(use_syslog) syslog(LOG_NOTICE, _("clamfi_connect: connection from %s [%s]"), hostname, remoteIP); cli_dbgmsg(_("clamfi_connect: connection from %s [%s]\n"), hostname, remoteIP); } } #endif #ifdef WITH_TCPWRAP /* * Support /etc/hosts.allow and /etc/hosts.deny */ if(strncasecmp(port, "inet:", 5) == 0) { const char *hostmail; struct hostent hostent; char buf[BUFSIZ]; static pthread_mutex_t wrap_mutex = PTHREAD_MUTEX_INITIALIZER; /* * Using TCP/IP for the sendmail->clamav-milter connection */ if((hostmail = smfi_getsymval(ctx, "{if_name}")) == NULL) { if(use_syslog) syslog(LOG_ERR, _("Can't get sendmail hostname")); return cl_error; } /* * Use hostmail for error statements, not hostname, suggestion * by Yar Tikhiy */ if(clamfi_gethostbyname(hostmail, &hostent, buf, sizeof(buf)) != 0) { if(use_syslog) syslog(LOG_WARNING, _("Access Denied: Host Unknown (%s)"), hostmail); if(hostmail[0] == '[') /* * A case could be made that it's not clamAV's * job to check a system's DNS configuration * and let this message through. However I am * just too worried about any knock on effects * to do that... */ cli_warnmsg(_("Can't find entry for IP address %s in DNS - check your DNS setting\n"), hostmail); return cl_error; } #ifdef HAVE_INET_NTOP if(hostent.h_addr && (inet_ntop(AF_INET, (struct in_addr *)hostent.h_addr, ip, sizeof(ip)) == NULL)) { perror(hostent.h_name); /*strcpy(ip, (char *)inet_ntoa(*(struct in_addr *)hostent.h_addr));*/ if(use_syslog) syslog(LOG_WARNING, _("Access Denied: Can't get IP address for (%s)"), hostent.h_name); return cl_error; } #else strncpy(ip, (char *)inet_ntoa(*(struct in_addr *)hostent.h_addr), sizeof(ip)); #endif /* * Ask is this is a allowed name or IP number * * hosts_ctl uses strtok so it is not thread safe, see * hosts_access(3) */ pthread_mutex_lock(&wrap_mutex); if(!hosts_ctl("clamav-milter", hostent.h_name, ip, STRING_UNKNOWN)) { pthread_mutex_unlock(&wrap_mutex); if(use_syslog) syslog(LOG_WARNING, _("Access Denied for %s[%s]"), hostent.h_name, ip); return SMFIS_TEMPFAIL; } pthread_mutex_unlock(&wrap_mutex); } #endif if(fflag) /* * Patch from "Richard G. Roberto" * Always scan whereever the message is from */ return SMFIS_CONTINUE; if(!oflag) if(strcmp(remoteIP, "127.0.0.1") == 0) { #ifdef CL_DEBUG if(use_syslog) syslog(LOG_DEBUG, _("clamfi_connect: not scanning outgoing messages")); cli_dbgmsg(_("clamfi_connect: not scanning outgoing messages\n")); #endif return SMFIS_ACCEPT; } if((!lflag) && isLocalAddr(inet_addr(remoteIP))) { #ifdef CL_DEBUG if(use_syslog) syslog(LOG_DEBUG, _("clamfi_connect: not scanning local messages")); cli_dbgmsg(_("clamfi_connect: not scanning local messages\n")); #endif return SMFIS_ACCEPT; } #if defined(HAVE_INET_NTOP) || defined(WITH_TCPWRAP) if(detect_forged_local_address && !isLocalAddr(inet_addr(ip))) { #else if(detect_forged_local_address && !isLocalAddr(inet_addr(remoteIP))) { #endif char me[MAXHOSTNAMELEN + 1]; if(gethostname(me, sizeof(me) - 1) < 0) { if(use_syslog) syslog(LOG_WARNING, _("clamfi_connect: gethostname failed")); return SMFIS_CONTINUE; } if(strcasecmp(hostname, me) == 0) { if(use_syslog) syslog(LOG_NOTICE, _("Rejected email falsely claiming to be from here")); smfi_setreply(ctx, "550", "5.7.1", _("You have claimed to be me, but you are not")); broadcast(_("Forged local address detected")); return SMFIS_REJECT; } } return SMFIS_CONTINUE; } static sfsistat clamfi_envfrom(SMFICTX *ctx, char **argv) { struct privdata *privdata; const char *mailaddr = argv[0]; if(logVerbose) syslog(LOG_DEBUG, "clamfi_envfrom: %s", argv[0]); cli_dbgmsg("clamfi_envfrom: %s\n", argv[0]); if(strcmp(argv[0], "<>") == 0) { mailaddr = smfi_getsymval(ctx, "{mail_addr}"); if(mailaddr == NULL) mailaddr = smfi_getsymval(ctx, "_"); if(mailaddr && *mailaddr) cli_dbgmsg("Message from \"%s\" has no from field\n", mailaddr); else { #if 0 if(use_syslog) syslog(LOG_NOTICE, _("Rejected email with empty from field")); smfi_setreply(ctx, "554", "5.7.1", _("You have not said who the email is from")); broadcast(_("Reject email with empty from field")); clamfi_cleanup(ctx); return SMFIS_REJECT; #endif mailaddr = "<>"; } } if(max_children > 0) { int rc = 0; pthread_mutex_lock(&n_children_mutex); /* * Wait a while since sendmail doesn't like it if we * take too long replying. Effectively this means that * max_children is more of a hint than a rule */ if(n_children >= max_children) { struct timespec timeout; cli_dbgmsg((dont_wait) ? _("hit max-children limit (%u >= %u)\n") : _("hit max-children limit (%u >= %u): waiting for some to exit\n"), n_children, max_children); if(use_syslog) syslog(LOG_NOTICE, (dont_wait) ? _("hit max-children limit (%u >= %u)") : _("hit max-children limit (%u >= %u): waiting for some to exit"), n_children, max_children); if(dont_wait) { pthread_mutex_unlock(&n_children_mutex); smfi_setreply(ctx, "451", "4.3.2", _("AV system temporarily overloaded - please try later")); return SMFIS_TEMPFAIL; } /* * Wait for an amount of time for a child to go (default * wait for ever) * * Use pthread_cond_timedwait rather than * pthread_cond_wait since the sendmail which calls * us will have a timeout that we don't want to exceed, * stops sendmail getting fidgety. * * Patch from Damian Menscher to * ensure it wakes up when a child goes away */ if(child_timeout) { struct timeval now; struct timezone tz; gettimeofday(&now, &tz); timeout.tv_sec = now.tv_sec + child_timeout; timeout.tv_nsec = 0; } do if(child_timeout == 0) rc = pthread_cond_wait(&n_children_cond, &n_children_mutex); else rc = pthread_cond_timedwait(&n_children_cond, &n_children_mutex, &timeout); while((n_children >= max_children) && (rc != ETIMEDOUT)); } n_children++; cli_dbgmsg(_(">n_children = %d\n"), n_children); pthread_mutex_unlock(&n_children_mutex); if(child_timeout && (rc == ETIMEDOUT)) { #ifdef CL_DEBUG if(use_syslog) syslog(LOG_NOTICE, _("Timeout waiting for a child to die")); #endif cli_dbgmsg(_("Timeout waiting for a child to die\n")); } } privdata = (struct privdata *)cli_calloc(1, sizeof(struct privdata)); if(privdata == NULL) return cl_error; privdata->dataSocket = -1; /* 0.4 */ #ifndef SESSION privdata->cmdSocket = -1; /* 0.4 */ #endif /* * Rejection is via 550 until DATA is received. We know that * DATA has been sent when either we get a header or the end of * header statement */ privdata->rejectCode = "550"; privdata->from = strdup(mailaddr); if(hflag) privdata->headers = header_list_new(); if(smfi_setpriv(ctx, privdata) == MI_SUCCESS) return SMFIS_CONTINUE; clamfi_free(privdata); return cl_error; } #ifdef CL_DEBUG static sfsistat clamfi_helo(SMFICTX *ctx, char *helostring) { cli_dbgmsg("HELO '%s'\n", helostring); return SMFIS_CONTINUE; } #endif static sfsistat clamfi_envrcpt(SMFICTX *ctx, char **argv) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); if(logVerbose) syslog(LOG_DEBUG, "clamfi_envrcpt: %s", argv[0]); cli_dbgmsg("clamfi_envrcpt: %s\n", argv[0]); if(privdata->to == NULL) { privdata->to = cli_malloc(sizeof(char *) * 2); assert(privdata->numTo == 0); } else privdata->to = cli_realloc(privdata->to, sizeof(char *) * (privdata->numTo + 2)); if(privdata->to == NULL) return cl_error; privdata->to[privdata->numTo] = strdup(argv[0]); privdata->to[++privdata->numTo] = NULL; return SMFIS_CONTINUE; } static sfsistat clamfi_header(SMFICTX *ctx, char *headerf, char *headerv) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); if(logVerbose) syslog(LOG_DEBUG, "clamfi_header: %s: %s", headerf, headerv); #ifdef CL_DEBUG if(debug_level >= 9) cli_dbgmsg("clamfi_header: %s: %s\n", headerf, headerv); else cli_dbgmsg("clamfi_header\n"); #endif /* * The DATA instruction from SMTP (RFC2821) must have been sent */ privdata->rejectCode = "554"; if(privdata->dataSocket == -1) /* * First header - make connection with clamd */ if(!connect2clamd(privdata)) { clamfi_cleanup(ctx); return cl_error; } if(clamfi_send(privdata, 0, "%s: %s\n", headerf, headerv) <= 0) { clamfi_cleanup(ctx); return cl_error; } if(hflag) header_list_add(privdata->headers, headerf, headerv); else if((strcasecmp(headerf, "Received") == 0) && (strncasecmp(headerv, "from ", 5) == 0) && (strstr(headerv, "localhost") != 0)) { if(privdata->received) free(privdata->received); privdata->received = strdup(headerv); } if((strcasecmp(headerf, "Message-ID") == 0) && (strncasecmp(headerv, "discard = 1; else if(strcasecmp(headerf, "Subject") == 0) { if(privdata->subject) free(privdata->subject); if(headerv) privdata->subject = strdup(headerv); } else if(strcasecmp(headerf, "X-Virus-Status") == 0) privdata->statusCount++; else if(strcasecmp(headerf, "Sender") == 0) { if(privdata->sender) free(privdata->sender); if(headerv) privdata->sender = strdup(headerv); } return SMFIS_CONTINUE; } /* * At this point DATA will have been received, so we really ought to * send 554 back not 550 */ static sfsistat clamfi_eoh(SMFICTX *ctx) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); char **to; if(logVerbose) syslog(LOG_DEBUG, _("clamfi_eoh")); #ifdef CL_DEBUG if(debug_level >= 4) cli_dbgmsg(_("clamfi_eoh\n")); #endif /* * The DATA instruction from SMTP (RFC2821) must have been sent */ privdata->rejectCode = "554"; if(privdata->dataSocket == -1) /* * No headers - make connection with clamd */ if(!connect2clamd(privdata)) { clamfi_cleanup(ctx); return cl_error; } if(detect_forged_local_address && privdata->from && (!privdata->sender) && !isWhitelisted(privdata->from)) { char me[MAXHOSTNAMELEN + 1]; const char *ptr; if(gethostname(me, sizeof(me) - 1) < 0) { if(use_syslog) syslog(LOG_WARNING, _("clamfi_eoh: gethostname failed")); return SMFIS_CONTINUE; } ptr = strstr(privdata->from, me); if(ptr && (ptr != privdata->from) && (*--ptr == '@')) { if(use_syslog) syslog(LOG_NOTICE, _("Rejected email falsely claiming to be from %s"), privdata->from); smfi_setreply(ctx, "554", "5.7.1", _("You have claimed to be from me, but you are not")); broadcast(_("Forged local address detected")); clamfi_cleanup(ctx); return SMFIS_REJECT; } } if(clamfi_send(privdata, 1, "\n") != 1) { clamfi_cleanup(ctx); return cl_error; } /* * See if the e-mail is only going to members of the list * of users we don't scan for. If it is, don't scan, otherwise * scan * * scan = false * FORALL recipients * IF receipient NOT MEMBER OF white address list * THEN * scan = true * FI * ENDFOR */ for(to = privdata->to; *to; to++) if(!isWhitelisted(*to)) /* * This recipient is not on the whitelist, * no need to check any further */ return SMFIS_CONTINUE; /* * Didn't find a recipient who is not on the white list, so all * must be on the white list, so just accept the e-mail */ if(use_syslog) syslog(LOG_NOTICE, _("clamfi_eoh: ignoring whitelisted message")); #ifdef CL_DEBUG cli_dbgmsg(_("clamfi_eoh: ignoring whitelisted message\n")); #endif clamfi_cleanup(ctx); return SMFIS_ACCEPT; } static sfsistat clamfi_body(SMFICTX *ctx, u_char *bodyp, size_t len) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); int nbytes; if(logVerbose) syslog(LOG_DEBUG, _("clamfi_envbody: %u bytes"), len); #ifdef CL_DEBUG cli_dbgmsg(_("clamfi_envbody: %u bytes\n"), len); #endif if(len == 0) /* unlikely */ return SMFIS_CONTINUE; nbytes = clamfi_send(privdata, len, (char *)bodyp); if(streamMaxLength > 0L) { if(privdata->numBytes > streamMaxLength) { if(use_syslog) { const char *sendmailId = smfi_getsymval(ctx, "i"); if(sendmailId == NULL) sendmailId = "Unknown"; syslog(LOG_NOTICE, _("%s: Message more than StreamMaxLength (%ld) bytes - not scanned"), sendmailId, streamMaxLength); } if(!nflag) smfi_addheader(ctx, "X-Virus-Status", _("Not Scanned - StreamMaxLength exceeded")); return SMFIS_ACCEPT; /* clamfi_close will be called */ } } if((size_t)nbytes < len) { clamfi_cleanup(ctx); /* not needed, but just to be safe */ return cl_error; } if(Sflag) { if(privdata->body) { assert(privdata->bodyLen > 0); privdata->body = cli_realloc(privdata->body, privdata->bodyLen + len); memcpy(&privdata->body[privdata->bodyLen], bodyp, len); privdata->bodyLen += len; } else { assert(privdata->bodyLen == 0); privdata->body = cli_malloc(len); memcpy(privdata->body, bodyp, len); privdata->bodyLen = len; } } return SMFIS_CONTINUE; } static sfsistat clamfi_eom(SMFICTX *ctx) { int rc = SMFIS_CONTINUE; char *ptr; const char *sendmailId; struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); char mess[128]; #ifdef SESSION struct session *session; #endif if(logVerbose) syslog(LOG_DEBUG, "clamfi_eom"); cli_dbgmsg("clamfi_eom\n"); if(!nflag) { /* * remove any existing claims that it's virus free so that * downstream checkers aren't fooled by a carefully crafted * virus. */ int i; for(i = privdata->statusCount; i > 0; --i) if(smfi_chgheader(ctx, "X-Virus-Status", i, NULL) == MI_FAILURE) if(use_syslog) syslog(LOG_WARNING, _("Failed to delete X-Virus-Status header %d"), i); } #ifdef CL_DEBUG assert(privdata != NULL); #ifndef SESSION assert((privdata->cmdSocket >= 0) || (privdata->filename != NULL)); assert(!((privdata->cmdSocket >= 0) && (privdata->filename != NULL))); #endif assert(privdata->dataSocket >= 0); #endif if(external) { close(privdata->dataSocket); privdata->dataSocket = -1; } if(!external) { const char *virname; unsigned long int scanned = 0L; /* * TODO: consider using cl_scandesc and not using a temporary * file from the mail being read in */ switch(cl_scanfile(privdata->filename, &virname, &scanned, root, &limits, options)) { case CL_CLEAN: strcpy(mess, "OK"); break; case CL_VIRUS: snprintf(mess, sizeof(mess), "%s: %s FOUND", privdata->filename, virname); logger(mess); break; default: snprintf(mess, sizeof(mess), "%s: %s ERROR", privdata->filename, cl_strerror(rc)); logger(mess); break; } #ifdef SESSION session = NULL; #endif } else if(privdata->filename) { char cmdbuf[1024]; /* * Create socket to talk to clamd. */ #ifndef SESSION struct sockaddr_un server; #endif int nbytes; snprintf(cmdbuf, sizeof(cmdbuf) - 1, "SCAN %s", privdata->filename); cli_dbgmsg("clamfi_eom: SCAN %s\n", privdata->filename); nbytes = (int)strlen(cmdbuf); #ifdef SESSION session = sessions; if(send(session->sock, cmdbuf, nbytes, 0) < nbytes) { perror("send"); clamfi_cleanup(ctx); if(use_syslog) syslog(LOG_ERR, _("failed to send SCAN %s command to clamd"), privdata->filename); return cl_error; } #else if((privdata->cmdSocket = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { perror("socket"); clamfi_cleanup(ctx); return cl_error; } memset((char *)&server, 0, sizeof(struct sockaddr_un)); server.sun_family = AF_UNIX; strncpy(server.sun_path, localSocket, sizeof(server.sun_path)); if(connect(privdata->cmdSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_un)) < 0) { perror(localSocket); clamfi_cleanup(ctx); return cl_error; } if(send(privdata->cmdSocket, cmdbuf, nbytes, 0) < nbytes) { perror("send"); clamfi_cleanup(ctx); if(use_syslog) syslog(LOG_ERR, _("failed to send SCAN command to clamd")); return cl_error; } shutdown(privdata->cmdSocket, SHUT_WR); #endif } #ifdef SESSION else session = &sessions[privdata->serverNumber]; #endif if(external) { int nbytes; #ifdef SESSION #ifdef CL_DEBUG if(debug_level >= 4) cli_dbgmsg(_("Waiting to read status from fd %d\n"), session->sock); #endif nbytes = clamd_recv(session->sock, mess, sizeof(mess) - 1); #else nbytes = clamd_recv(privdata->cmdSocket, mess, sizeof(mess) - 1); #endif if(nbytes > 0) { mess[nbytes] = '\0'; if((ptr = strchr(mess, '\n')) != NULL) *ptr = '\0'; if(logVerbose) syslog(LOG_DEBUG, _("clamfi_eom: read %s"), mess); cli_dbgmsg(_("clamfi_eom: read %s\n"), mess); } else { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; cli_strtokbuf(serverHostNames, privdata->serverNumber, ":", hostname); if(strcmp(hostname, "127.0.0.1") == 0) gethostname(hostname, sizeof(hostname)); #else char *hostname = cli_strtok(serverHostNames, privdata->serverNumber, ":"); #endif /* * TODO: if more than one host has been specified, try * another one - setting cl_error to SMFIS_TEMPFAIL * helps by forcing a retry */ clamfi_cleanup(ctx); syslog(LOG_NOTICE, _("clamfi_eom: read nothing from clamd on %s"), hostname); #ifdef CL_DEBUG cli_dbgmsg(_("clamfi_eom: read nothing from clamd on %s\n"), hostname); #endif #ifdef SESSION pthread_mutex_lock(&sstatus_mutex); session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); #endif return cl_error; } #ifdef SESSION pthread_mutex_lock(&sstatus_mutex); if(session->status == CMDSOCKET_INUSE) session->status = CMDSOCKET_FREE; pthread_mutex_unlock(&sstatus_mutex); #else close(privdata->cmdSocket); privdata->cmdSocket = -1; #endif } sendmailId = smfi_getsymval(ctx, "i"); if(sendmailId == NULL) sendmailId = "Unknown"; if(!nflag) { char buf[1024]; /* * Include the hostname where the scan took place */ if(localSocket || !external) { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; #else char hostname[65]; #endif if(gethostname(hostname, sizeof(hostname)) < 0) { const char *j = smfi_getsymval(ctx, "{j}"); if(j) strncpy(hostname, j, sizeof(hostname) - 1); else strcpy(hostname, _("Error determining host")); } else if(strchr(hostname, '.') == NULL) { /* * Determine fully qualified name */ struct hostent hostent; if(clamfi_gethostbyname(hostname, &hostent, buf, sizeof(buf)) == 0) strncpy(hostname, hostent.h_name, sizeof(hostname)); } #ifdef SESSION pthread_mutex_lock(&version_mutex); snprintf(buf, sizeof(buf) - 1, "%s on %s", clamav_versions[privdata->serverNumber], hostname); pthread_mutex_unlock(&version_mutex); #else snprintf(buf, sizeof(buf) - 1, "%s on %s", clamav_version, hostname); #endif } else { #ifdef MAXHOSTNAMELEN char hostname[MAXHOSTNAMELEN + 1]; if(cli_strtokbuf(serverHostNames, privdata->serverNumber, ":", hostname)) { if(strcmp(hostname, "127.0.0.1") == 0) gethostname(hostname, sizeof(hostname)); #else char *hostname = cli_strtok(serverHostNames, privdata->serverNumber, ":"); if(hostname) { #endif #ifdef SESSION pthread_mutex_lock(&version_mutex); snprintf(buf, sizeof(buf) - 1, "%s on %s", clamav_versions[privdata->serverNumber], hostname); pthread_mutex_unlock(&version_mutex); #else snprintf(buf, sizeof(buf) - 1, "%s on %s", clamav_version, hostname); #endif #ifndef MAXHOSTNAMELEN free(hostname); #endif } else /* sanity check failed - should issue warning */ strcpy(buf, _("Error determining host")); } smfi_addheader(ctx, "X-Virus-Scanned", buf); } if(strstr(mess, "ERROR") != NULL) { if(strstr(mess, "Size limit reached") != NULL) { /* * Clamd has stopped on StreamMaxLength before us */ if(use_syslog) syslog(LOG_NOTICE, _("%s: Message more than StreamMaxLength (%ld) bytes - not scanned"), sendmailId, streamMaxLength); if(!nflag) smfi_addheader(ctx, "X-Virus-Status", _("Not Scanned - StreamMaxLength exceeded")); clamfi_cleanup(ctx); /* not needed, but just to be safe */ return SMFIS_ACCEPT; } if(!nflag) smfi_addheader(ctx, "X-Virus-Status", _("Not Scanned")); cli_warnmsg("%s: %s\n", sendmailId, mess); if(use_syslog) syslog(LOG_ERR, "%s: %s\n", sendmailId, mess); rc = cl_error; } else if((ptr = strstr(mess, "FOUND")) != NULL) { /* * Fixme: This will give false positives if the * word "FOUND" is in the email, e.g. the * quarantine directory is /tmp/VIRUSES-FOUND */ char reject[1024]; char **to, *virusname; /* Remove the "FOUND" word, and the space before it */ *--ptr = '\0'; /* skip over 'stream/filename: ' at the start */ if((virusname = strchr(mess, ':')) != NULL) virusname = &virusname[2]; else virusname = mess; if(!nflag) { char buf[129]; snprintf(buf, sizeof(buf) - 1, "%s %s", _("Infected with"), virusname); smfi_addheader(ctx, "X-Virus-Status", buf); } if(use_syslog) { /* * Setup err as a list of recipients */ char *err = (char *)cli_malloc(1024); int i; if(err == NULL) { clamfi_cleanup(ctx); return cl_error; } /* * Use snprintf rather than printf since we don't know * the length of privdata->from and may get a buffer * overrun */ snprintf(err, 1023, _("Intercepted virus from %s to"), privdata->from); ptr = strchr(err, '\0'); i = 1024; for(to = privdata->to; *to; to++) { /* * Re-alloc if we are about run out of buffer space */ if(&ptr[strlen(*to) + 2] >= &err[i]) { i += 1024; err = cli_realloc(err, i); if(err == NULL) { clamfi_cleanup(ctx); return cl_error; } ptr = strchr(err, '\0'); } ptr = strrcpy(ptr, " "); ptr = strrcpy(ptr, *to); } (void)strcpy(ptr, "\n"); /* Include the sendmail queue ID in the log */ syslog(LOG_NOTICE, "%s: %s %s", sendmailId, mess, err); #ifdef CL_DEBUG cli_dbgmsg("%s", err); #endif free(err); } if(quarantine_dir != NULL) qfile(privdata, sendmailId, virusname); if(!qflag) { char cmd[128]; FILE *sendmail; /* * If the oflag is given this sendmail command * will cause the mail being generated here to be * scanned. So if oflag is given we just put the * item in the queue so there's no scanning of two * messages at once. It'll still be scanned, but * not at the same time as the incoming message * * FIXME: there is a race condition here when sendmail * and clamav-milter run on the same machine. If the * system is very overloaded this sendmail can * take a long time to start - and may even fail * is the LA is > REFUSE_LA. In all the time we're * taking to start this sendmail, the sendmail that's * started us may timeout waiting for a response and * let the virus through (albeit tagged with * X-Virus-Status: Infected) because we haven't * sent SMFIS_DISCARD or SMFIS_REJECT * * -i flag, suggested by Michal Jaegermann * */ snprintf(cmd, sizeof(cmd) - 1, (oflag || fflag) ? "%s -t -i -odq" : "%s -t -i", SENDMAIL_BIN); cli_dbgmsg("Calling %s\n", cmd); sendmail = popen(cmd, "w"); if(sendmail) { if(from && from[0]) fprintf(sendmail, "From: %s\n", from); else fprintf(sendmail, "From: %s\n", privdata->from); if(bflag && privdata->from) { fprintf(sendmail, "To: %s\n", privdata->from); fprintf(sendmail, "Cc: %s\n", postmaster); } else fprintf(sendmail, "To: %s\n", postmaster); if((!pflag) && privdata->to) for(to = privdata->to; *to; to++) fprintf(sendmail, "Cc: %s\n", *to); /* * Auto-submitted is still a draft, keep an * eye on its format */ fputs("Auto-Submitted: auto-submitted (antivirus notify)\n", sendmail); /* "Sergey Y. Afonin" */ if((ptr = smfi_getsymval(ctx, "{_}")) != NULL) fprintf(sendmail, "X-Infected-Received-From: %s\n", ptr); fputs(_("Subject: Virus intercepted\n\n"), sendmail); if((templatefile == NULL) || (sendtemplate(ctx, templatefile, sendmail, virusname) < 0)) { /* * Use our own hardcoded template */ if(bflag) fputs(_("A message you sent to\n"), sendmail); else if(pflag) /* * The message is only going to * the postmaster, so include * some useful information */ fprintf(sendmail, _("The message %1$s sent from %2$s to\n"), sendmailId, privdata->from); else fprintf(sendmail, _("A message sent from %s to\n"), privdata->from); for(to = privdata->to; *to; to++) fprintf(sendmail, "\t%s\n", *to); fprintf(sendmail, _("contained %s and has not been delivered.\n"), virusname); if(quarantine_dir != NULL) fprintf(sendmail, _("\nThe message in question has been quarantined as %s\n"), privdata->filename); if(hflag) { fprintf(sendmail, _("\nThe message was received by %1$s from %2$s via %3$s\n\n"), smfi_getsymval(ctx, "j"), privdata->from, smfi_getsymval(ctx, "_")); fputs(_("For your information, the original message headers were:\n\n"), sendmail); header_list_print(privdata->headers, sendmail); } else if(privdata->received) /* * TODO: parse this to find * real infected machine. * Need to decide how to find * if it's a dynamic IP from a * dial up account in which * case there may not be much * we can do if that DHCP has * set the hostname... */ fprintf(sendmail, _("\nThe infected machine is likely to be here:\n%s\t\n"), privdata->received); } cli_dbgmsg("Waiting for %s to finish\n", cmd); pclose(sendmail); } else if(use_syslog) syslog(LOG_WARNING, _("Can't execute '%s' to send virus notice"), cmd); } if(quarantine_dir) { if(use_syslog) syslog(LOG_NOTICE, _("Quarantined infected mail as %s"), privdata->filename); /* * Cleanup filename here otherwise clamfi_free() will * delete the file that we wish to keep because it * is infected */ free(privdata->filename); privdata->filename = NULL; } if(quarantine) { for(to = privdata->to; *to; to++) { smfi_delrcpt(ctx, *to); smfi_addheader(ctx, "X-Original-To", *to); free(*to); } free(privdata->to); privdata->to = NULL; /* * NOTE: on a closed relay this will not work * if the recipient is a remote address */ if(smfi_addrcpt(ctx, quarantine) == MI_FAILURE) { if(use_syslog) syslog(LOG_ERR, _("Can't set quarantine user %s"), quarantine); else cli_warnmsg(_("Can't set quarantine user %s\n"), quarantine); rc = (privdata->discard) ? SMFIS_DISCARD : SMFIS_REJECT; } else { if(use_syslog) syslog(LOG_DEBUG, "Redirected virus to %s", quarantine); cli_dbgmsg("Redirected virus to %s\n", quarantine); setsubject(ctx, virusname); } } else if(advisory) setsubject(ctx, virusname); else if(rejectmail) { if(privdata->discard) rc = SMFIS_DISCARD; else rc = SMFIS_REJECT; /* Delete the e-mail */ } else rc = SMFIS_DISCARD; /* * Don't drop the message if it's been forwarded to a * quarantine email */ snprintf(reject, sizeof(reject) - 1, _("virus %s detected by ClamAV - http://www.clamav.net"), virusname); smfi_setreply(ctx, (char *)privdata->rejectCode, "5.7.1", reject); broadcast(mess); } else if(strstr(mess, "OK") == NULL) { if(!nflag) smfi_addheader(ctx, "X-Virus-Status", _("Unknown")); if(use_syslog) syslog(LOG_ERR, _("%s: incorrect message \"%s\" from clamd"), sendmailId, mess); rc = cl_error; } else { if(!nflag) smfi_addheader(ctx, "X-Virus-Status", _("Clean")); if(use_syslog && logClean) /* Include the sendmail queue ID in the log */ syslog(LOG_NOTICE, _("%s: clean message from %s"), sendmailId, (privdata->from) ? privdata->from : _("an unknown sender")); if(privdata->body) { /* * Add a signature that all has been scanned OK */ off_t len = updateSigFile(); if(len) { assert(Sflag != 0); privdata->body = cli_realloc(privdata->body, privdata->bodyLen + len); if(privdata->body) { memcpy(&privdata->body[privdata->bodyLen], signature, len); smfi_replacebody(ctx, privdata->body, privdata->bodyLen + len); } } } } clamfi_cleanup(ctx); return rc; } static sfsistat clamfi_abort(SMFICTX *ctx) { #ifdef CL_DEBUG if(logVerbose) syslog(LOG_DEBUG, "clamfi_abort"); #endif cli_dbgmsg("clamfi_abort\n"); /* * Unlock incase we're called during a cond_timedwait in envfrom * * TODO: There *must* be a tidier a safer way of doing this! */ if((max_children > 0) && (n_children >= max_children)) { (void)pthread_mutex_trylock(&n_children_mutex); (void)pthread_mutex_unlock(&n_children_mutex); } clamfi_cleanup(ctx); cli_dbgmsg("clamfi_abort returns\n"); return cl_error; } static sfsistat clamfi_close(SMFICTX *ctx) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); cli_dbgmsg("clamfi_close\n"); if(privdata != NULL) clamfi_cleanup(ctx); if(logVerbose) syslog(LOG_DEBUG, "clamfi_close"); return SMFIS_CONTINUE; } static void clamfi_cleanup(SMFICTX *ctx) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); cli_dbgmsg("clamfi_cleanup\n"); if(privdata) { clamfi_free(privdata); smfi_setpriv(ctx, NULL); } } static void clamfi_free(struct privdata *privdata) { cli_dbgmsg("clamfi_free\n"); if(privdata) { #ifdef SESSION struct session *session; #endif if(privdata->body) free(privdata->body); if(privdata->dataSocket >= 0) { close(privdata->dataSocket); privdata->dataSocket = -1; } if(privdata->filename != NULL) { /* * Don't print an error if the file hasn't been * created yet */ if((unlink(privdata->filename) < 0) && (errno != ENOENT)) { perror(privdata->filename); if(use_syslog) syslog(LOG_ERR, _("Can't remove clean file %s"), privdata->filename); } free(privdata->filename); privdata->filename = NULL; } if(privdata->from) { #ifdef CL_DEBUG if(debug_level >= 9) cli_dbgmsg("Free privdata->from\n"); #endif free(privdata->from); privdata->from = NULL; } if(privdata->subject) { free(privdata->subject); privdata->subject = NULL; } if(privdata->sender) { free(privdata->sender); privdata->sender = NULL; } if(privdata->to) { char **to; for(to = privdata->to; *to; to++) { #ifdef CL_DEBUG if(debug_level >= 9) cli_dbgmsg("Free *privdata->to\n"); #endif free(*to); } #ifdef CL_DEBUG if(debug_level >= 9) cli_dbgmsg("Free privdata->to\n"); #endif free(privdata->to); privdata->to = NULL; } if(external) { #ifdef SESSION session = &sessions[privdata->serverNumber]; pthread_mutex_lock(&sstatus_mutex); if(session->status == CMDSOCKET_INUSE) { /* * Probably we've got here because * StreamMaxLength has been reached */ #if 0 pthread_mutex_unlock(&sstatus_mutex); if(readTimeout) { char buf[64]; const int fd = session->sock; cli_dbgmsg("clamfi_free: flush server %d fd %d\n", privdata->serverNumber, fd); /* * FIXME: whenever this code gets * executed, all of the PINGs fail * in the next watchdog cycle */ while(clamd_recv(fd, buf, sizeof(buf)) > 0) ; } pthread_mutex_lock(&sstatus_mutex); #endif /* Force a reset */ session->status = CMDSOCKET_DOWN; } pthread_mutex_unlock(&sstatus_mutex); #else if(privdata->cmdSocket >= 0) { char buf[64]; /* * Flush the remote end so that clamd doesn't * get a SIGPIPE */ if(readTimeout) while(clamd_recv(privdata->cmdSocket, buf, sizeof(buf)) > 0) ; close(privdata->cmdSocket); privdata->cmdSocket = -1; } #endif } if(privdata->headers) header_list_free(privdata->headers); #ifdef CL_DEBUG if(debug_level >= 9) cli_dbgmsg("Free privdata\n"); #endif if(privdata->received) free(privdata->received); free(privdata); } if(max_children > 0) { pthread_mutex_lock(&n_children_mutex); cli_dbgmsg("clamfi_free: n_children = %d\n", n_children); /* * Deliberately errs on the side of broadcasting too many times */ if(n_children > 0) if(--n_children == 0) { cli_dbgmsg("clamav-milter is idle\n"); if(pthread_cond_broadcast(&watchdog_cond) < 0) perror("pthread_cond_broadcast"); } #ifdef CL_DEBUG cli_dbgmsg("pthread_cond_broadcast\n"); #endif if(pthread_cond_broadcast(&n_children_cond) < 0) perror("pthread_cond_broadcast"); cli_dbgmsg(" 0) /* * It isn't a NUL terminated string. We have a set number of * bytes to output. */ ptr = format; else { va_list argp; va_start(argp, format); vsnprintf(output, sizeof(output) - 1, format, argp); va_end(argp); len = strlen(output); ptr = output; } #ifdef CL_DEBUG if(debug_level >= 9) { time_t t; const struct tm *tm; time(&t); tm = localtime(&t); cli_dbgmsg("%d:%d:%d clamfi_send: len=%u bufsiz=%u, fd=%d\n", tm->tm_hour, tm->tm_min, tm->tm_sec, len, sizeof(output), privdata->dataSocket); } #endif while(len > 0) { const int nbytes = (privdata->filename) ? write(privdata->dataSocket, ptr, len) : send(privdata->dataSocket, ptr, len, 0); assert(privdata->dataSocket >= 0); if(nbytes == -1) { if(privdata->filename) { perror(privdata->filename); if(use_syslog) { #ifdef HAVE_STRERROR_R char buf[32]; strerror_r(errno, buf, sizeof(buf)); syslog(LOG_ERR, _("write failure (%u bytes) to %s: %s"), len, privdata->filename, buf); #else syslog(LOG_ERR, _("write failure (%u bytes) to %s: %s"), len, privdata->filename, strerror(errno)); #endif } } else { if(errno == EINTR) continue; perror("send"); if(use_syslog) { #ifdef HAVE_STRERROR_R char buf[32]; strerror_r(errno, buf, sizeof(buf)); syslog(LOG_ERR, _("write failure (%u bytes) to clamd: %s"), len, buf); #else syslog(LOG_ERR, _("write failure (%u bytes) to clamd: %s"), len, strerror(errno)); #endif } checkClamd(); } return -1; } ret += nbytes; len -= nbytes; ptr = &ptr[nbytes]; if(streamMaxLength > 0L) { privdata->numBytes += nbytes; if(privdata->numBytes >= streamMaxLength) break; } } return ret; } /* * Like strcpy, but return the END of the destination, allowing a quicker * means of adding to the end of a string than strcat */ #if 0 static char * strrcpy(char *dest, const char *source) { /* Pre assertions */ assert(dest != NULL); assert(source != NULL); assert(dest != source); while((*dest++ = *source++) != '\0') ; return(--dest); } #endif /* * Read from clamav - timeout if necessary */ static int clamd_recv(int sock, char *buf, size_t len) { fd_set rfds; struct timeval tv; assert(sock >= 0); if(readTimeout == 0) return recv(sock, buf, len, 0); FD_ZERO(&rfds); FD_SET(sock, &rfds); tv.tv_sec = readTimeout; tv.tv_usec = 0; switch(select(sock + 1, &rfds, NULL, NULL, &tv)) { case -1: perror("select"); return -1; case 0: if(use_syslog) syslog(LOG_ERR, _("No data received from clamd in %d seconds\n"), readTimeout); return 0; } return recv(sock, buf, len, 0); } /* * Read in the signature file */ static off_t updateSigFile(void) { struct stat statb; int fd; if(sigFilename == NULL) /* nothing to read */ return 0; if(stat(sigFilename, &statb) < 0) { perror(sigFilename); if(use_syslog) syslog(LOG_ERR, _("Can't stat %s"), sigFilename); return 0; } if(statb.st_mtime <= signatureStamp) return statb.st_size; /* not changed */ fd = open(sigFilename, O_RDONLY); if(fd < 0) { perror(sigFilename); if(use_syslog) syslog(LOG_ERR, _("Can't open %s"), sigFilename); return 0; } signatureStamp = statb.st_mtime; signature = cli_realloc(signature, statb.st_size); if(signature) read(fd, signature, statb.st_size); close(fd); return statb.st_size; } static header_list_t header_list_new(void) { header_list_t ret; ret = (header_list_t)cli_malloc(sizeof(struct header_list_struct)); if(ret) { ret->first = NULL; ret->last = NULL; } return ret; } static void header_list_free(header_list_t list) { struct header_node_t *iter; iter = list->first; while (iter) { struct header_node_t *iter2 = iter->next; free(iter->header); free(iter); iter = iter2; } free(list); } static void header_list_add(header_list_t list, const char *headerf, const char *headerv) { char *header; size_t len; struct header_node_t *new_node; len = (size_t)(strlen(headerf) + strlen(headerv) + 3); header = (char *)cli_malloc(len); if(header == NULL) return; sprintf(header, "%s: %s", headerf, headerv); new_node = (struct header_node_t *)cli_malloc(sizeof(struct header_node_t)); if(new_node == NULL) { free(header); return; } new_node->header = header; new_node->next = NULL; if(list->first == NULL) list->first = new_node; if(list->last) list->last->next = new_node; list->last = new_node; } static void header_list_print(const header_list_t list, FILE *fp) { const struct header_node_t *iter; if(list == NULL) return; for(iter = list->first; iter; iter = iter->next) { if(strncmp(iter->header, "From ", 5) == 0) putc('>', fp); fprintf(fp, "%s\n", iter->header); } } /* * Establish a connection to clamd * Returns success (1) or failure (0) */ static int connect2clamd(struct privdata *privdata) { assert(privdata != NULL); assert(privdata->dataSocket == -1); assert(privdata->from != NULL); assert(privdata->to != NULL); #ifdef CL_DEBUG if((debug_level > 0) && use_syslog) syslog(LOG_DEBUG, "connect2clamd"); if(debug_level >= 4) cli_dbgmsg("connect2clamd\n"); #endif if(quarantine_dir || tmpdir) { /* store message in a temporary file */ int ntries = 5; const char *dir = (tmpdir) ? tmpdir : quarantine_dir; /* * TODO: investigate mkdtemp on LINUX and possibly others */ #ifdef C_AIX /* * Patch by Andy Feldt , AIX 5.2 sets errno * to ENOENT often and sometimes sets errno to 0 (after a * database reload) for the mkdir call */ if((mkdir(dir, 0700) < 0) && (errno != EEXIST) && (errno > 0) && (errno != ENOENT)) { #else if((mkdir(dir, 0700) < 0) && (errno != EEXIST)) { #endif perror(dir); if(use_syslog) syslog(LOG_ERR, _("mkdir %s failed"), dir); return 0; } privdata->filename = (char *)cli_malloc(strlen(dir) + 12); do { sprintf(privdata->filename, "%s/msg.XXXXXX", dir); #if defined(C_LINUX) || defined(C_BSD) || defined(HAVE_MKSTEMP) || defined(C_SOLARIS) privdata->dataSocket = mkstemp(privdata->filename); #else if(mktemp(privdata->filename) == NULL) { if(use_syslog) syslog(LOG_ERR, _("mktemp %s failed"), privdata->filename); return 0; } privdata->dataSocket = open(privdata->filename, O_CREAT|O_EXCL|O_WRONLY|O_TRUNC, 0600); #endif } while((--ntries > 0) && (privdata->dataSocket < 0)); if(privdata->dataSocket < 0) { perror(privdata->filename); if(use_syslog) syslog(LOG_ERR, _("Temporary quarantine file %s creation failed"), privdata->filename); return 0; } privdata->serverNumber = 0; cli_dbgmsg("Saving message to %s to scan later\n", privdata->filename); } else { /* communicate to clamd */ int freeServer, nbytes; struct sockaddr_in reply; unsigned short p; char buf[64]; #ifdef SESSION struct session *session; #else assert(privdata->cmdSocket == -1); #endif /* * Create socket to talk to clamd. It will tell us the port to * use to send the data. That will require another socket. */ if(localSocket) { #ifndef SESSION struct sockaddr_un server; memset((char *)&server, 0, sizeof(struct sockaddr_un)); server.sun_family = AF_UNIX; strncpy(server.sun_path, localSocket, sizeof(server.sun_path)); if((privdata->cmdSocket = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { perror("socket"); return 0; } if(connect(privdata->cmdSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_un)) < 0) { perror(localSocket); return 0; } privdata->serverNumber = 0; #endif freeServer = 0; } else { /* TCP/IP */ #ifdef SESSION freeServer = findServer(); if(freeServer < 0) return 0; assert(freeServer < (int)max_children); #else struct sockaddr_in server; memset((char *)&server, 0, sizeof(struct sockaddr_in)); server.sin_family = AF_INET; server.sin_port = (in_port_t)htons(tcpSocket); assert(serverIPs != NULL); freeServer = findServer(); if(freeServer < 0) return 0; assert(freeServer < (int)max_children); server.sin_addr.s_addr = serverIPs[freeServer]; if((privdata->cmdSocket = socket(AF_INET, SOCK_STREAM, 0)) < 0) { perror("socket"); return 0; } if(connect(privdata->cmdSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) < 0) { perror("connect"); return 0; } #endif privdata->serverNumber = freeServer; } #ifdef SESSION if(serverIPs[freeServer] == (int)inet_addr("127.0.0.1")) { privdata->filename = cli_gentemp(NULL); if(privdata->filename) { cli_dbgmsg("connect2clamd(%d): creating %s\n", freeServer, privdata->filename); #ifdef O_TEXT privdata->dataSocket = open(privdata->filename, O_WRONLY|O_CREAT|O_EXCL|O_TRUNC|O_TEXT, 0600); #else privdata->dataSocket = open(privdata->filename, O_WRONLY|O_CREAT|O_EXCL|O_TRUNC, 0600); #endif if(privdata->dataSocket < 0) { perror(privdata->filename); free(privdata->filename); privdata->filename = NULL; } else return sendToFrom(privdata); } } cli_dbgmsg("connect2clamd(%d): STREAM\n", freeServer); session = &sessions[freeServer]; if((session->sock < 0) || (send(session->sock, "STREAM\n", 7, 0) < 7)) { perror("send"); pthread_mutex_lock(&sstatus_mutex); session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); cli_warnmsg("Failed sending stream to server %d (fd %d) errno %d\n", freeServer, session->sock, errno); if(use_syslog) syslog(LOG_ERR, _("failed to send STREAM command clamd server %d"), freeServer); return 0; } #else if(send(privdata->cmdSocket, "STREAM\n", 7, 0) < 7) { perror("send"); if(use_syslog) syslog(LOG_ERR, _("failed to send STREAM command clamd")); return 0; } shutdown(privdata->cmdSocket, SHUT_WR); #endif /* * Create socket that we'll use to send the data to clamd */ if((privdata->dataSocket = socket(AF_INET, SOCK_STREAM, 0)) < 0) { perror("socket"); if(use_syslog) syslog(LOG_ERR, _("failed to create TCPSocket to talk to clamd")); return 0; } shutdown(privdata->dataSocket, SHUT_RD); #ifdef SESSION nbytes = clamd_recv(session->sock, buf, sizeof(buf)); if(nbytes <= 0) { if(nbytes < 0) { perror("recv"); if(use_syslog) syslog(LOG_ERR, _("recv failed from clamd getting PORT")); cli_warnmsg("Failed get PORT from server %d (fd %d) errno %d\n", freeServer, session->sock, errno); } else if(use_syslog) syslog(LOG_ERR, _("EOF from clamd getting PORT")); pthread_mutex_lock(&sstatus_mutex); session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); return 0; } #else nbytes = clamd_recv(privdata->cmdSocket, buf, sizeof(buf)); if(nbytes <= 0) { if(nbytes < 0) { perror("recv"); if(use_syslog) syslog(LOG_ERR, _("recv failed from clamd getting PORT")); } else if(use_syslog) syslog(LOG_ERR, _("EOF from clamd getting PORT")); return 0; } #endif buf[nbytes] = '\0'; #ifdef CL_DEBUG if(debug_level >= 4) cli_dbgmsg("Received: %s", buf); #endif if(sscanf(buf, "PORT %hu\n", &p) != 1) { if(use_syslog) syslog(LOG_ERR, _("Expected port information from clamd, got '%s'"), buf); else cli_warnmsg(_("Expected port information from clamd, got '%s'\n"), buf); #ifdef SESSION session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); #endif return 0; } memset((char *)&reply, 0, sizeof(struct sockaddr_in)); reply.sin_family = AF_INET; reply.sin_port = (in_port_t)htons(p); assert(serverIPs != NULL); reply.sin_addr.s_addr = serverIPs[freeServer]; #ifdef CL_DEBUG if(debug_level >= 4) #ifdef SESSION cli_dbgmsg(_("Connecting to local port %d - data %d cmd %d\n"), p, privdata->dataSocket, session->sock); #else cli_dbgmsg(_("Connecting to local port %d - data %d cmd %d\n"), p, privdata->dataSocket, privdata->cmdSocket); #endif #endif if(connect(privdata->dataSocket, (struct sockaddr *)&reply, sizeof(struct sockaddr_in)) < 0) { perror("connect"); cli_dbgmsg("Failed to connect to port %d given by clamd", p); /* 0.4 - use better error message */ if(use_syslog) { #ifdef HAVE_STRERROR_R strerror_r(errno, buf, sizeof(buf)); syslog(LOG_ERR, _("Failed to connect to port %d given by clamd: %s"), p, buf); #else syslog(LOG_ERR, _("Failed to connect to port %d given by clamd: %s"), p, strerror(errno)); #endif } #ifdef SESSION pthread_mutex_lock(&sstatus_mutex); session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); #endif return 0; } } if(!sendToFrom(privdata)) return 0; cli_dbgmsg("connect2clamd: serverNumber = %d\n", privdata->serverNumber); return 1; } /* * Combine the To and From into one clamfi_send to save bandwidth * when sending using TCP/IP to connect to a remote clamd, by band * width here I mean number of packets */ static int sendToFrom(struct privdata *privdata) { char **to; char *msg; int length; length = strlen(privdata->from) + 34; for(to = privdata->to; *to; to++) length += strlen(*to) + 5; msg = cli_malloc(length + 1); if(msg) { sprintf(msg, "Received: by clamav-milter\nFrom: %s\n", privdata->from); for(to = privdata->to; *to; to++) { char *eom = strchr(msg, '\0'); sprintf(eom, "To: %s\n", *to); } if(clamfi_send(privdata, length, msg) != length) { free(msg); return 0; } free(msg); } else { clamfi_send(privdata, 0, "Received: by clamav-milter\nFrom: %s\n", privdata->from); for(to = privdata->to; *to; to++) if(clamfi_send(privdata, 0, "To: %s\n", *to) <= 0) return 0; } return 1; } /* * If possible, check if clamd has died, and report if it has */ static void checkClamd(void) { pid_t pid; int fd, nbytes; char buf[9]; if(!localSocket) return; /* communicating via TCP */ if(pidFile == NULL) return; /* PidFile directive missing from clamd.conf */ fd = open(pidFile, O_RDONLY); if(fd < 0) { perror(pidFile); if(use_syslog) syslog(LOG_ERR, _("Can't open %s"), pidFile); return; } nbytes = read(fd, buf, sizeof(buf) - 1); if(nbytes < 0) perror(pidFile); else buf[nbytes] = '\0'; close(fd); pid = atoi(buf); if((kill(pid, 0) < 0) && (errno == ESRCH)) { if(use_syslog) syslog(LOG_ERR, _("Clamd (pid %d) seems to have died"), pid); perror("clamd"); } } /* * Send a templated message about an intercepted message. Very basic for * now, just to prove it works, will enhance the flexability later, only * supports %v and $sendmail_variables$ at present. * * TODO: more template features * TODO: allow filename to start with a '|' taken to mean the output of * a program */ static int sendtemplate(SMFICTX *ctx, const char *filename, FILE *sendmail, const char *virusname) { FILE *fin = fopen(filename, "r"); struct stat statb; char *buf, *ptr /* , *ptr2 */; struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); if(fin == NULL) { perror(filename); if(use_syslog) syslog(LOG_ERR, _("Can't open e-mail template file %s"), filename); return -1; } if(fstat(fileno(fin), &statb) < 0) { /* File disappeared in race condition? */ perror(filename); if(use_syslog) syslog(LOG_ERR, _("Can't stat e-mail template file %s"), filename); fclose(fin); return -1; } buf = cli_malloc(statb.st_size + 1); if(buf == NULL) { fclose(fin); if(use_syslog) syslog(LOG_ERR, _("Out of memory")); return -1; } fread(buf, sizeof(char), statb.st_size, fin); fclose(fin); buf[statb.st_size] = '\0'; for(ptr = buf; *ptr; ptr++) switch(*ptr) { case '%': /* clamAV variable */ switch(*++ptr) { case 'v': /* virus name */ fputs(virusname, sendmail); break; case '%': putc('%', sendmail); break; case 'h': /* headers */ if(privdata) header_list_print(privdata->headers, sendmail); break; case '\0': putc('%', sendmail); --ptr; continue; default: syslog(LOG_ERR, _("%s: Unknown clamAV variable \"%c\"\n"), filename, *ptr); break; } break; case '$': /* sendmail string */ { const char *val; char *end = strchr(++ptr, '$'); if(end == NULL) { syslog(LOG_ERR, _("%s: Unterminated sendmail variable \"%s\"\n"), filename, ptr); continue; } *end = '\0'; val = smfi_getsymval(ctx, ptr); if(val == NULL) { fputs(ptr, sendmail); if(use_syslog) syslog(LOG_ERR, _("%s: Unknown sendmail variable \"%s\"\n"), filename, ptr); } else fputs(val, sendmail); ptr = end; break; } case '\\': if(*++ptr == '\0') { --ptr; continue; } putc(*ptr, sendmail); break; default: putc(*ptr, sendmail); } free(buf); return 0; } /* * Keep the infected file in quarantine, return success (0) or failure */ static int qfile(struct privdata *privdata, const char *sendmailId, const char *virusname) { int MM, YY, DD; time_t t; size_t len; char *newname, *ptr; const struct tm *tm; assert(privdata != NULL); if((privdata->filename == NULL) || (virusname == NULL)) return -1; cli_dbgmsg("qfile filename '%s' sendmailId '%s' virusname '%s'\n", privdata->filename, sendmailId, virusname); len = strlen(quarantine_dir); newname = cli_malloc(len + strlen(sendmailId) + strlen(virusname) + 10); if(newname == NULL) return -1; t = time((time_t *)0); tm = localtime(&t); MM = tm->tm_mon + 1; YY = tm->tm_year - 100; DD = tm->tm_mday; sprintf(newname, "%s/%02d%02d%02d", quarantine_dir, YY, MM, DD); #ifdef C_AIX if((mkdir(newname, 0700) < 0) && (errno != EEXIST) && (errno > 0) && (errno != ENOENT)) { #else if((mkdir(newname, 0700) < 0) && (errno != EEXIST)) { #endif perror(newname); if(use_syslog) syslog(LOG_ERR, _("mkdir %s failed"), newname); return -1; } sprintf(newname, "%s/%02d%02d%02d/%s.%s", quarantine_dir, YY, MM, DD, sendmailId, virusname); /* * Strip out funnies that may be in the name of the virus, such as '/' * that would cause the quarantine to fail to save since the name * of the virus is included in the filename */ for(ptr = &newname[len + 8]; *ptr; ptr++) { #ifdef C_DARWIN *ptr &= '\177'; #endif #if defined(MSDOS) || defined(C_CYGWIN) || defined(WIN32) || defined(C_OS2) if(strchr("/*?<>|\\\"+=,;:\t ", *ptr)) #else if(*ptr == '/') #endif *ptr = '_'; } cli_dbgmsg("qfile move '%s' to '%s'\n", privdata->filename, newname); if(move(privdata->filename, newname) < 0) { if(use_syslog) syslog(LOG_WARNING, _("Can't rename %1$s to %2$s"), privdata->filename, newname); free(newname); return -1; } free(privdata->filename); privdata->filename = newname; if(use_syslog) syslog(LOG_INFO, _("File quarantined as %s"), newname); return 0; } /* * Move oldfile to newfile using the fastest possible method */ static int move(const char *oldfile, const char *newfile) { int ret; #ifdef C_LINUX struct stat statb; int fin, fout; off_t offset; #else FILE *fin, *fout; int c; #endif ret = rename(oldfile, newfile); if(ret >= 0) return 0; if((ret < 0) && (errno != EXDEV)) { perror(newfile); return -1; } #ifdef C_LINUX /* >= 2.2 */ fin = open(oldfile, O_RDONLY); if(fin < 0) { perror(oldfile); return -1; } if(fstat(fin, &statb) < 0) { perror(oldfile); close(fin); return -1; } fout = open(newfile, O_WRONLY|O_CREAT, 0600); if(fout < 0) { perror(newfile); close(fin); return -1; } offset = (off_t)0; ret = sendfile(fout, fin, &offset, statb.st_size); close(fin); if(ret < 0) { perror(newfile); close(fout); unlink(newfile); return -1; } close(fout); #else fin = fopen(oldfile, "r"); if(fin == NULL) return -1; fout = fopen(newfile, "w"); if(fout == NULL) { fclose(fin); return -1; } while((c = getc(fin)) != EOF) putc(c, fout); fclose(fin); fclose(fout); #endif cli_dbgmsg("removing %s\n", oldfile); return unlink(oldfile); } /* * Store the name of the virus in the subject of the e-mail */ static void setsubject(SMFICTX *ctx, const char *virusname) { struct privdata *privdata = (struct privdata *)smfi_getpriv(ctx); char subject[128]; if(privdata->subject) smfi_addheader(ctx, "X-Original-Subject", privdata->subject); snprintf(subject, sizeof(subject) - 1, _("[Virus] %s"), virusname); if(privdata->subject) smfi_chgheader(ctx, "Subject", 1, subject); else smfi_addheader(ctx, "Subject", subject); } /* * TODO: gethostbyname_r is non-standard so different operating * systems do it in different ways. Need more examples * Perhaps we could use res_search()? * * Returns 0 for success */ static int clamfi_gethostbyname(const char *hostname, struct hostent *hp, char *buf, size_t len) { #if defined(HAVE_GETHOSTBYNAME_R_6) /* e.g. Linux */ struct hostent *hp2; int ret = -1; if((hostname == NULL) || (hp == NULL)) return -1; if(gethostbyname_r(hostname, hp, buf, len, &hp2, &ret) < 0) return ret; #elif defined(HAVE_GETHOSTBYNAME_R_5) /* e.g. BSD, Solaris, Cygwin */ int ret = -1; if((hostname == NULL) || (hp == NULL)) return -1; if(gethostbyname_r(hostname, hp, buf, len, &ret) == NULL) return ret; #elif defined(HAVE_GETHOSTBYNAME_R_3) /* e.g. HP/UX, AIX */ if((hostname == NULL) || (hp == NULL)) return -1; if(gethostbyname_r(hostname, &hp, (struct hostent_data *)buf) < 0) return h_errno; #else /* Single thread the code */ struct hostent *hp2; static pthread_mutex_t hostent_mutex = PTHREAD_MUTEX_INITIALIZER; if((hostname == NULL) || (hp == NULL)) return -1; pthread_mutex_lock(&hostent_mutex); if((hp2 = gethostbyname(hostname)) == NULL) { pthread_mutex_unlock(&hostent_mutex); return h_errno; } memcpy(hp, hp2, sizeof(struct hostent)); pthread_mutex_unlock(&hostent_mutex); #endif return 0; } /* * David Champion * * Check whether addr is on network by applying netmasks. * addr must be a 32-bit integer-packed IPv4 address in network order. * For example: * struct in_addr IPAddress; * isLocal = isLocalAddr(IPAddress.s_addr); */ static int isLocalAddr(in_addr_t addr) { const struct cidr_net *net; for(net = localNets; net->base; net++) if(htonl(net->base & net->mask) == (addr & htonl(net->mask))) return 1; return 0; /* is non-local */ } /* * Can't connect to any clamd server. This is serious, we need to inform * someone. In the absence of SNMP the best way is by e-mail. We * don't want to flood so there's a need to restrict to * no more than say one message every 15 minutes */ static void clamdIsDown(void) { static time_t lasttime; time_t thistime, diff; static pthread_mutex_t time_mutex = PTHREAD_MUTEX_INITIALIZER; cli_errmsg(_("No response from any clamd server - your AV system is not scanning emails\n")); if(use_syslog) syslog(LOG_ERR, _("No response from any clamd server - your AV system is not scanning emails")); time(&thistime); pthread_mutex_lock(&time_mutex); diff = thistime - lasttime; pthread_mutex_unlock(&time_mutex); if(diff >= (time_t)(15 * 60)) { char cmd[128]; FILE *sendmail; snprintf(cmd, sizeof(cmd) - 1, "%s -t -i", SENDMAIL_BIN); sendmail = popen(cmd, "w"); if(sendmail) { fprintf(sendmail, "To: %s\n", postmaster); fprintf(sendmail, "From: %s\n", postmaster); fputs(_("Subject: ClamAV Down\n"), sendmail); fputs("Priority: High\n\n", sendmail); fputs(_("This is an automatic message\n\n"), sendmail); if(numServers == 1) fputs(_("The clamd program cannot be contacted.\n"), sendmail); else fputs(_("No clamd server can be contacted.\n"), sendmail); fputs(_("Emails may not be being scanned, please check your servers.\n"), sendmail); if(pclose(sendmail) == 0) { pthread_mutex_lock(&time_mutex); time(&lasttime); pthread_mutex_unlock(&time_mutex); } } } } #ifdef SESSION /* * Thread to monitor the links to clamd sessions. Any marked as being in * an error state because of previous I/O errors are restarted, and a heartbeat * is sent the others * * It is woken up when the milter goes idle, when there are no free servers * available and once every readTimeout-1 seconds * * TODO: reload the whiteList file if it's been changed * * TODO: localSocket support */ static void * watchdog(void *a) { static pthread_mutex_t watchdog_mutex = PTHREAD_MUTEX_INITIALIZER; assert((!external) || (sessions != NULL)); while(!quitting) { unsigned int i; struct timespec ts; struct timeval tp; struct session *session; gettimeofday(&tp, NULL); ts.tv_sec = tp.tv_sec + readTimeout - 1; ts.tv_nsec = tp.tv_usec * 1000; cli_dbgmsg("watchdog sleeps\n"); pthread_mutex_lock(&watchdog_mutex); /* * Sometimes this returns EPIPE which isn't listed as a * return value in the Linux man page for pthread_cond_timedwait * so I'm not sure why it happens */ switch(pthread_cond_timedwait(&watchdog_cond, &watchdog_mutex, &ts)) { case ETIMEDOUT: case 0: break; default: perror("pthread_cond_timedwait"); } cli_dbgmsg("watchdog wakes\n"); pthread_mutex_unlock(&watchdog_mutex); if(!external) { int dbstatus = cl_statchkdir(&dbstat); /* * Re-load the database if the server's not busy. * TODO: If a reload is needed go into a mode when * new scans aren't accepted, to force the number * of children to 0 so that we can reload, * otherwise a reload may not occur on overloaded * servers */ pthread_mutex_lock(&n_children_mutex); if((n_children == 0) && (dbstatus == 1)) { pthread_mutex_lock(&accept_mutex); accept_inputs = 0; pthread_mutex_unlock(&accept_mutex); cli_dbgmsg("Database has changed\n"); cl_statfree(&dbstat); /* check for race condition */ while(n_children > 0) pthread_cond_wait(&n_children_cond, &n_children_mutex); if(use_syslog) syslog(LOG_WARNING, _("Loading new database")); if(loadDatabase() != 0) { pthread_mutex_unlock(&n_children_mutex); smfi_stop(); return NULL; } pthread_mutex_lock(&accept_mutex); accept_inputs = 1; pthread_cond_broadcast(&accept_cond); pthread_mutex_unlock(&accept_mutex); } else if(dbstatus == 0) cli_dbgmsg("Database has not changed\n"); else if(dbstatus == 1) { cli_warnmsg("Not reloading database until idle - waiting for %d children\n", n_children); pthread_mutex_lock(&accept_mutex); accept_inputs = 0; pthread_mutex_unlock(&accept_mutex); while(n_children > 0) { pthread_cond_wait(&n_children_cond, &n_children_mutex); cli_warnmsg("Waiting for %d children until databae reload\n", n_children); } cl_statfree(&dbstat); if(use_syslog) syslog(LOG_WARNING, _("Loading new database")); if(loadDatabase() != 0) { pthread_mutex_unlock(&n_children_mutex); smfi_stop(); return NULL; } pthread_mutex_lock(&accept_mutex); accept_inputs = 1; pthread_cond_broadcast(&accept_cond); pthread_mutex_unlock(&accept_mutex); } else { smfi_stop(); cli_errmsg("Database error - clamav-milter is stopping\n"); pthread_mutex_unlock(&n_children_mutex); return NULL; } pthread_mutex_unlock(&n_children_mutex); continue; } i = 0; session = sessions; pthread_mutex_lock(&sstatus_mutex); for(; i < max_children; i++, session++) { const int sock = session->sock; /* * Check all free sessions are still usable * This could take some time with many free * sessions to slow remote servers, so only do this * when the system is quiet (not 100% accurate when * determining this since n_children isn't locked but * that doesn't really matter) */ cli_dbgmsg("watchdog: check server %d\n", i); if((n_children == 0) && (session->status == CMDSOCKET_FREE) && (clamav_versions != NULL)) { if(send(sock, "VERSION\n", 8, 0) == 8) { char buf[81]; const int nbytes = clamd_recv(sock, buf, sizeof(buf) - 1); if(nbytes <= 0) session->status = CMDSOCKET_DOWN; else { buf[nbytes] = '\0'; if(strncmp(buf, "ClamAV ", 7) == 0) { /* Remove the trailing new line from the reply */ char *ptr; if((ptr = strchr(buf, '\n')) != NULL) *ptr = '\0'; pthread_mutex_lock(&version_mutex); if(clamav_versions[i] == NULL) clamav_versions[i] = strdup(buf); else if(strcmp(buf, clamav_versions[i]) != 0) { if(use_syslog) syslog(LOG_INFO, "New version received for server %d: '%s'\n", i, buf); free(clamav_versions[i]); clamav_versions[i] = strdup(buf); } pthread_mutex_unlock(&version_mutex); } else { cli_warnmsg("watchdog: expected \"ClamAV\", got \"%s\"\n", buf); session->status = CMDSOCKET_DOWN; } } } else { perror("send"); session->status = CMDSOCKET_DOWN; } if(session->status == CMDSOCKET_DOWN) cli_warnmsg("Session %d has gone down\n", i); } /* * Reset all all dead sessions */ if(session->status == CMDSOCKET_DOWN) { /* * The END command probably won't get through, * but let's give it a go anyway */ if(sock >= 0) { send(sock, "END\n", 4, 0); close(sock); } cli_dbgmsg("Trying to restart session %d\n", i); if(createSession(i) == 0) { session->status = CMDSOCKET_FREE; cli_warnmsg("Session %d restarted OK\n", i); } } } for(i = 0; i < max_children; i++) if(sessions[i].status != CMDSOCKET_DOWN) break; if(i == max_children) clamdIsDown(); pthread_mutex_unlock(&sstatus_mutex); } cli_dbgmsg("watchdog quits\n"); return NULL; } #else /*!SESSION*/ /* * Reload the database from time to time, when using the internal scanner * * TODO: reload the whiteList file if it's been changed */ /*ARGSUSED*/ static void * watchdog(void *a) { static pthread_mutex_t watchdog_mutex = PTHREAD_MUTEX_INITIALIZER; if(external) return NULL; while(!quitting) { struct timespec ts; struct timeval tp; int dbstatus; gettimeofday(&tp, NULL); ts.tv_sec = tp.tv_sec + readTimeout - 1; ts.tv_nsec = tp.tv_usec * 1000; cli_dbgmsg("watchdog sleeps\n"); pthread_mutex_lock(&watchdog_mutex); /* * Sometimes this returns EPIPE which isn't listed as a * return value in the Linux man page for pthread_cond_timedwait * so I'm not sure why it happens */ switch(pthread_cond_timedwait(&watchdog_cond, &watchdog_mutex, &ts)) { case ETIMEDOUT: case 0: break; default: perror("pthread_cond_timedwait"); } cli_dbgmsg("watchdog wakes\n"); pthread_mutex_unlock(&watchdog_mutex); /* * Re-load the database if the server's not busy. * TODO: If a reload is needed go into a mode when * new scans aren't accepted, to force the number * of children to 0 so that we can reload, * otherwise a reload may not occur on overloaded * servers */ dbstatus = cl_statchkdir(&dbstat); pthread_mutex_lock(&n_children_mutex); if((n_children == 0) && (dbstatus == 1)) { pthread_mutex_lock(&accept_mutex); accept_inputs = 0; pthread_mutex_unlock(&accept_mutex); cli_dbgmsg("Database has changed\n"); cl_statfree(&dbstat); /* check for race condition */ while(n_children > 0) pthread_cond_wait(&n_children_cond, &n_children_mutex); if(use_syslog) syslog(LOG_WARNING, _("Loading new database")); if(loadDatabase() != 0) { pthread_mutex_unlock(&n_children_mutex); smfi_stop(); return NULL; } pthread_mutex_lock(&accept_mutex); accept_inputs = 1; pthread_cond_broadcast(&accept_cond); pthread_mutex_unlock(&accept_mutex); } else if(dbstatus == 0) cli_dbgmsg("Database has not changed\n"); else if(dbstatus == 1) { cli_warnmsg("Not reloading database until idle - waiting for %d children\n", n_children); pthread_mutex_lock(&accept_mutex); accept_inputs = 0; pthread_mutex_unlock(&accept_mutex); while(n_children > 0) { pthread_cond_wait(&n_children_cond, &n_children_mutex); cli_warnmsg("Waiting for %d children until databae reload\n", n_children); } cl_statfree(&dbstat); if(use_syslog) syslog(LOG_WARNING, _("Loading new database")); if(loadDatabase() != 0) { pthread_mutex_unlock(&n_children_mutex); smfi_stop(); return NULL; } pthread_mutex_lock(&accept_mutex); accept_inputs = 1; if(pthread_cond_broadcast(&accept_cond) < 0) perror("pthread_cond_broadcast"); pthread_mutex_unlock(&accept_mutex); } else { smfi_stop(); cli_errmsg("Database error - clamav-milter is stopping\n"); pthread_mutex_unlock(&n_children_mutex); return NULL; } pthread_mutex_unlock(&n_children_mutex); } cli_dbgmsg("watchdog quits\n"); return NULL; } #endif static const struct { const char *name; int code; } facilitymap[] = { #ifdef LOG_AUTH { "LOG_AUTH", LOG_AUTH }, #endif #ifdef LOG_AUTHPRIV { "LOG_AUTHPRIV", LOG_AUTHPRIV }, #endif #ifdef LOG_CRON { "LOG_CRON", LOG_CRON }, #endif #ifdef LOG_DAEMON { "LOG_DAEMON", LOG_DAEMON }, #endif #ifdef LOG_FTP { "LOG_FTP", LOG_FTP }, #endif #ifdef LOG_KERN { "LOG_KERN", LOG_KERN }, #endif #ifdef LOG_LPR { "LOG_LPR", LOG_LPR }, #endif #ifdef LOG_MAIL { "LOG_MAIL", LOG_MAIL }, #endif #ifdef LOG_NEWS { "LOG_NEWS", LOG_NEWS }, #endif #ifdef LOG_AUTH { "LOG_AUTH", LOG_AUTH }, #endif #ifdef LOG_SYSLOG { "LOG_SYSLOG", LOG_SYSLOG }, #endif #ifdef LOG_USER { "LOG_USER", LOG_USER }, #endif #ifdef LOG_UUCP { "LOG_UUCP", LOG_UUCP }, #endif #ifdef LOG_LOCAL0 { "LOG_LOCAL0", LOG_LOCAL0 }, #endif #ifdef LOG_LOCAL1 { "LOG_LOCAL1", LOG_LOCAL1 }, #endif #ifdef LOG_LOCAL2 { "LOG_LOCAL2", LOG_LOCAL2 }, #endif #ifdef LOG_LOCAL3 { "LOG_LOCAL3", LOG_LOCAL3 }, #endif #ifdef LOG_LOCAL4 { "LOG_LOCAL4", LOG_LOCAL4 }, #endif #ifdef LOG_LOCAL5 { "LOG_LOCAL5", LOG_LOCAL5 }, #endif #ifdef LOG_LOCAL6 { "LOG_LOCAL6", LOG_LOCAL6 }, #endif #ifdef LOG_LOCAL7 { "LOG_LOCAL7", LOG_LOCAL7 }, #endif { NULL, -1 } }; static int logg_facility(const char *name) { int i; for(i = 0; facilitymap[i].name; i++) if(strcasecmp(facilitymap[i].name, name) == 0) return facilitymap[i].code; return -1; } static void quit(void) { extern short cli_leavetemps_flag; quitting++; pthread_mutex_lock(&accept_mutex); accept_inputs = 0; pthread_mutex_unlock(&accept_mutex); #ifdef SESSION pthread_mutex_lock(&version_mutex); #endif if(use_syslog) syslog(LOG_INFO, _("Stopping %s"), clamav_version); #ifdef SESSION pthread_mutex_unlock(&version_mutex); #endif if(!external) { if(root) { cl_free(root); root = NULL; } } else { #ifdef SESSION int i = 0; struct session *session = sessions; pthread_mutex_lock(&sstatus_mutex); for(; i < ((localSocket != NULL) ? 1 : (int)max_children); i++) { /* * Check all free sessions are still usable * This could take some time with many free * sessions to slow remote servers, so only do this * when the system is quiet (not 100% accurate when * determining this since n_children isn't locked but * that doesn't really matter) */ cli_dbgmsg("quit: close server %d\n", i); if(session->status == CMDSOCKET_FREE) { const int sock = session->sock; send(sock, "END\n", 4, 0); shutdown(sock, SHUT_WR); session->status = CMDSOCKET_DOWN; pthread_mutex_unlock(&sstatus_mutex); close(sock); pthread_mutex_lock(&sstatus_mutex); } session++; } pthread_mutex_unlock(&sstatus_mutex); #endif } if(tmpdir && !cli_leavetemps_flag) if(rmdir(tmpdir) < 0) perror(tmpdir); broadcast(_("Stopping clamav-milter")); if(pidfile) if(unlink(pidfile) < 0) perror(pidfile); if(use_syslog) closelog(); } static void broadcast(const char *mess) { struct sockaddr_in s; if(broadcastSock < 0) return; memset(&s, '\0', sizeof(struct sockaddr_in)); s.sin_family = AF_INET; s.sin_port = (in_port_t)htons(tcpSocket ? tcpSocket : 3310); s.sin_addr.s_addr = htonl(INADDR_BROADCAST); cli_dbgmsg("broadcast %s to %d\n", mess, broadcastSock); if(sendto(broadcastSock, mess, strlen(mess), 0, (struct sockaddr *)&s, sizeof(struct sockaddr_in)) < 0) perror("sendto"); } /* * Load a new database into the internal scanner - it is up to the caller to * ensure that no threads are currently scanning */ static int loadDatabase(void) { extern const char *cl_retdbdir(void); /* FIXME: should be included */ int ret, v; unsigned int signatures; time_t t; char *daily, *ptr; struct cl_cvd *d; const struct cfgstruct *cpt; static const char *dbdir; assert(!external); if(dbdir == NULL) { if((cpt = cfgopt(copt, "DatabaseDirectory")) || (cpt = cfgopt(copt, "DataDirectory"))) dbdir = cpt->strarg; else dbdir = cl_retdbdir(); } daily = cli_malloc(strlen(dbdir) + 11); sprintf(daily, "%s/daily.cvd", dbdir); cli_dbgmsg("loadDatabase: check %s for updates\n", daily); d = cl_cvdhead(daily); if(d == NULL) { cli_errmsg("Can't find %s\n", daily); free(daily); return -1; } t = d->stime; v = d->version; cl_cvdfree(d); free(daily); #ifdef SESSION pthread_mutex_lock(&version_mutex); if(clamav_versions == NULL) { clamav_versions = (char **)cli_malloc(sizeof(char *)); if(clamav_versions == NULL) { pthread_mutex_unlock(&version_mutex); return -1; } clamav_version = cli_malloc(VERSION_LENGTH + 1); if(clamav_version == NULL) { free(clamav_versions); clamav_versions = NULL; pthread_mutex_unlock(&version_mutex); return -1; } } pthread_mutex_unlock(&version_mutex); #endif snprintf(clamav_version, VERSION_LENGTH, "ClamAV %s/%d/%s", VERSION, v, ctime(&t)); /* Remove ctime's trailing \n */ if((ptr = strchr(clamav_version, '\n')) != NULL) *ptr = '\0'; if(root) { cl_free(root); root = NULL; } signatures = 0; ret = cl_loaddbdir(dbdir, &root, &signatures); if(ret != 0) { cli_errmsg("%s\n", cl_strerror(ret)); return -1; } if(root == NULL) { cli_errmsg("Can't initialize the virus database.\n"); return -1; } ret = cl_build(root); if(ret != 0) { cli_errmsg("Database initialization error: %s\n", cl_strerror(ret)); return -1; } cli_dbgmsg("Database updated\n"); if(use_syslog) { syslog(LOG_INFO, _("ClamAV: Protecting against %u viruses"), signatures); #ifdef SESSION pthread_mutex_lock(&version_mutex); #endif syslog(LOG_INFO, _("Loaded %s"), clamav_version); #ifdef SESSION pthread_mutex_unlock(&version_mutex); #endif } return cl_statinidir(dbdir, &dbstat); } static void sigsegv(int sig) { signal(SIGSEGV, SIG_DFL); #ifdef HAVE_BACKTRACE print_trace(); #endif if(use_syslog) syslog(LOG_ERR, "Segmentation fault :-( Bye.."); cli_errmsg("Segmentation fault :-( Bye..\n"); smfi_stop(); } #ifdef HAVE_BACKTRACE static void print_trace(void) { void *array[BACKTRACE_SIZE]; size_t size, i; char **strings; pid_t pid = getpid(); size = backtrace(array, BACKTRACE_SIZE); strings = backtrace_symbols(array, size); cli_dbgmsg("Backtrace of pid %d:\n", pid); if(use_syslog) syslog(LOG_ERR, "Backtrace of pid %d:", pid); for(i = 0; i < size; i++) { if(use_syslog) syslog(LOG_ERR, "bt[%u]: %s", i, strings[i]); cli_dbgmsg("%s\n", strings[i]); } /* TODO: dump the current email */ free(strings); } #endif /* * Check that the correct port name has been given, i.e. that the * input socket to clamav-milter from sendmail, is the same that * sendmail has been configured to use as it's output socket * Return: <0 invalid * =0 valid * >0 unknown */ static int verifyIncomingSocketName(const char *sockName) { #if HAVE_MMAP int fd, ret; char *ptr; size_t size; struct stat statb; if(strncmp(sockName, "inet:", 5) == 0) /* * clamav-milter is running on a different machine from sendmail */ return 1; if(sendmailCF) fd = open(sendmailCF, O_RDONLY); else { fd = open("/etc/mail/sendmail.cf", O_RDONLY); if(fd < 0) fd = open("/etc/sendmail.cf", O_RDONLY); } if(fd < 0) return 1; if(fstat(fd, &statb) < 0) { close(fd); return 1; } size = statb.st_size; if(size == 0) { close(fd); return -1; } ptr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0); if(ptr == MAP_FAILED) { perror("mmap"); close(fd); return -1; } ret = (cli_memstr(ptr, size, sockName, strlen(sockName)) != NULL) ? 1 : -1; munmap(ptr, size); close(fd); return ret; #else /*!HAVE_MMAP*/ return 1; #endif } /* * If the given email address is whitelisted don't scan their emails * * TODO: Allow regular expressions in the emails * TODO: Syntax check the contents of the files * TODO: Allow emails of the form "name
" */ static int isWhitelisted(const char *emailaddress) { static table_t *whitelist; if((whitelist == NULL) && whitelistFile) { FILE *fin; char buf[BUFSIZ + 1]; fin = fopen(whitelistFile, "r"); if(fin == NULL) { perror(whitelistFile); return 0; } whitelist = tableCreate(); while(fgets(buf, sizeof(buf), fin) != NULL) { /* comment line? */ switch(buf[0]) { case '#': case '/': case ':': continue; } if(cli_chomp(buf) > 0) (void)tableInsert(whitelist, buf, 1); } fclose(fin); } if(whitelist && (tableFind(whitelist, emailaddress) == 1)) /* * This recipient is on the whitelist */ return 1; /* * Don't scan messages to the quarantine email address */ if(quarantine && (strcasecmp(quarantine, emailaddress) == 0)) return 1; return 0; } static void logger(const char *mess) { #ifdef CL_DEBUG puts(mess); #else FILE *fout = fopen(logFile, "a"); if(fout == NULL) return; if(logTime) { #ifdef HAVE_CTIME_R time_t currtime = time((time_t)0); char buf[27]; #ifdef HAVE_CTIME_R_3 ctime_r(&currtime, buf, sizeof(buf)); #else ctime_r(&currtime, buf); #endif fprintf(fout, "%.*s -> %s\n", (int)strlen(buf) - 1, buf, mess); #else /*!HAVE_CTIME_R*/ /* TODO */ fprintf(fout, "%s\n", mess); #endif } else fprintf(fout, "%s\n", mess); fclose(fout); #endif }