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Diffstat (limited to 'src/malware.c')
| -rw-r--r-- | src/malware.c | 2299 |
1 files changed, 2299 insertions, 0 deletions
diff --git a/src/malware.c b/src/malware.c new file mode 100644 index 0000000..ef85d3d --- /dev/null +++ b/src/malware.c @@ -0,0 +1,2299 @@ +/************************************************* +* Exim - an Internet mail transport agent * +*************************************************/ + +/* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003 - 2015 + * License: GPL + * Copyright (c) The Exim Maintainers 2015 - 2020 + */ + +/* Code for calling virus (malware) scanners. Called from acl.c. */ + +#include "exim.h" +#ifdef WITH_CONTENT_SCAN /* entire file */ + +typedef enum { +#ifndef DISABLE_MAL_FFROTD + M_FPROTD, +#endif +#ifndef DISABLE_MAL_FFROT6D + M_FPROT6D, +#endif +#ifndef DISABLE_MAL_DRWEB + M_DRWEB, +#endif +#ifndef DISABLE_MAL_AVE + M_AVES, +#endif +#ifndef DISABLE_MAL_FSECURE + M_FSEC, +#endif +#ifndef DISABLE_MAL_KAV + M_KAVD, +#endif +#ifndef DISABLE_MAL_SOPHIE + M_SOPHIE, +#endif +#ifndef DISABLE_MAL_CLAM + M_CLAMD, +#endif +#ifndef DISABLE_MAL_MKS + M_MKSD, +#endif +#ifndef DISABLE_MAL_AVAST + M_AVAST, +#endif +#ifndef DISABLE_MAL_SOCK + M_SOCK, +#endif +#ifndef DISABLE_MAL_CMDLINE + M_CMDL, +#endif + M_DUMMY + } scanner_t; +typedef enum {MC_NONE, MC_TCP, MC_UNIX, MC_STRM} contype_t; +static struct scan +{ + scanner_t scancode; + const uschar * name; + const uschar * options_default; + contype_t conn; +} m_scans[] = +{ +#ifndef DISABLE_MAL_FFROTD + { M_FPROTD, US"f-protd", US"localhost 10200-10204", MC_TCP }, +#endif +#ifndef DISABLE_MAL_FFROT6D + { M_FPROT6D, US"f-prot6d", US"localhost 10200", MC_TCP }, +#endif +#ifndef DISABLE_MAL_DRWEB + { M_DRWEB, US"drweb", US"/usr/local/drweb/run/drwebd.sock", MC_STRM }, +#endif +#ifndef DISABLE_MAL_AVE + { M_AVES, US"aveserver", US"/var/run/aveserver", MC_UNIX }, +#endif +#ifndef DISABLE_MAL_FSECURE + { M_FSEC, US"fsecure", US"/var/run/.fsav", MC_UNIX }, +#endif +#ifndef DISABLE_MAL_KAV + { M_KAVD, US"kavdaemon", US"/var/run/AvpCtl", MC_UNIX }, +#endif +#ifndef DISABLE_MAL_SOPHIE + { M_SOPHIE, US"sophie", US"/var/run/sophie", MC_UNIX }, +#endif +#ifndef DISABLE_MAL_CLAM + { M_CLAMD, US"clamd", US"/tmp/clamd", MC_NONE }, +#endif +#ifndef DISABLE_MAL_MKS + { M_MKSD, US"mksd", NULL, MC_NONE }, +#endif +#ifndef DISABLE_MAL_AVAST + { M_AVAST, US"avast", US"/var/run/avast/scan.sock", MC_STRM }, +#endif +#ifndef DISABLE_MAL_SOCK + { M_SOCK, US"sock", US"/tmp/malware.sock", MC_STRM }, +#endif +#ifndef DISABLE_MAL_CMDLINE + { M_CMDL, US"cmdline", NULL, MC_NONE }, +#endif + { -1, NULL, NULL, MC_NONE } /* end-marker */ +}; + +/******************************************************************************/ +# ifdef MACRO_PREDEF /* build solely to predefine macros */ + +# include "macro_predef.h" + +void +features_malware(void) +{ +const uschar * s; +uschar * t; +uschar buf[EXIM_DRIVERNAME_MAX]; + +spf(buf, sizeof(buf), US"_HAVE_MALWARE_"); + +for (const struct scan * sc = m_scans; sc->scancode != -1; sc++) + { + for (s = sc->name, t = buf+14; *s; s++) if (*s != '-') + *t++ = toupper(*s); + *t = '\0'; + builtin_macro_create(buf); + } +} + +/******************************************************************************/ +# else /*!MACRO_PREDEF, main build*/ + + +#define MALWARE_TIMEOUT 120 /* default timeout, seconds */ + +static const uschar * malware_regex_default = US ".+"; +static const pcre * malware_default_re = NULL; + + + +#ifndef DISABLE_MAL_CLAM +/* The maximum number of clamd servers that are supported in the configuration */ +# define MAX_CLAMD_SERVERS 32 +# define MAX_CLAMD_SERVERS_S "32" + +typedef struct clamd_address { + uschar * hostspec; + unsigned tcp_port; + unsigned retry; +} clamd_address; +#endif + + +#ifndef DISABLE_MAL_DRWEB +# define DRWEBD_SCAN_CMD (1) /* scan file, buffer or diskfile */ +# define DRWEBD_RETURN_VIRUSES (1<<0) /* ask daemon return to us viruses names from report */ +# define DRWEBD_IS_MAIL (1<<19) /* say to daemon that format is "archive MAIL" */ + +# define DERR_READ_ERR (1<<0) /* read error */ +# define DERR_NOMEMORY (1<<2) /* no memory */ +# define DERR_TIMEOUT (1<<9) /* scan timeout has run out */ +# define DERR_BAD_CALL (1<<15) /* wrong command */ + +static const uschar * drweb_re_str = US "infected\\swith\\s*(.+?)$"; +static const pcre * drweb_re = NULL; +#endif + +#ifndef DISABLE_MAL_FSECURE +static const uschar * fsec_re_str = US "\\S{0,5}INFECTED\\t[^\\t]*\\t([^\\t]+)\\t\\S*$"; +static const pcre * fsec_re = NULL; +#endif + +#ifndef DISABLE_MAL_KAV +static const uschar * kav_re_sus_str = US "suspicion:\\s*(.+?)\\s*$"; +static const uschar * kav_re_inf_str = US "infected:\\s*(.+?)\\s*$"; +static const pcre * kav_re_sus = NULL; +static const pcre * kav_re_inf = NULL; +#endif + +#ifndef DISABLE_MAL_AVAST +static const uschar * ava_re_clean_str = US "(?!\\\\)\\t\\[\\+\\]"; +static const uschar * ava_re_virus_str = US "(?!\\\\)\\t\\[L\\]\\d+\\.0\\t0\\s(.*)"; +static const uschar * ava_re_error_str = US "(?!\\\\)\\t\\[E\\]\\d+\\.0\\tError\\s\\d+\\s(.*)"; +static const pcre * ava_re_clean = NULL; +static const pcre * ava_re_virus = NULL; +static const pcre * ava_re_error = NULL; +#endif + +#ifndef DISABLE_MAL_FFROT6D +static const uschar * fprot6d_re_error_str = US "^\\d+\\s<(.+?)>$"; +static const uschar * fprot6d_re_virus_str = US "^\\d+\\s<infected:\\s+(.+?)>\\s+.+$"; +static const pcre * fprot6d_re_error = NULL; +static const pcre * fprot6d_re_virus = NULL; +#endif + + + +/******************************************************************************/ + +#ifndef DISABLE_MAL_KAV +/* Routine to check whether a system is big- or little-endian. + Ripped from http://www.faqs.org/faqs/graphics/fileformats-faq/part4/section-7.html + Needed for proper kavdaemon implementation. Sigh. */ +# define BIG_MY_ENDIAN 0 +# define LITTLE_MY_ENDIAN 1 +static int test_byte_order(void); +static inline int +test_byte_order() +{ + short int word = 0x0001; + char *byte = CS &word; + return(byte[0] ? LITTLE_MY_ENDIAN : BIG_MY_ENDIAN); +} +#endif + +BOOL malware_ok = FALSE; + +/* Gross hacks for the -bmalware option; perhaps we should just create +the scan directory normally for that case, but look into rigging up the +needed header variables if not already set on the command-line? */ +extern int spool_mbox_ok; +extern uschar spooled_message_id[MESSAGE_ID_LENGTH+1]; + + +/* Some (currently avast only) use backslash escaped whitespace, +this function undoes these escapes */ + +static inline void +unescape(uschar *p) +{ +uschar *p0; +for (; *p; ++p) + if (*p == '\\' && (isspace(p[1]) || p[1] == '\\')) + for (p0 = p; *p0; ++p0) *p0 = p0[1]; +} + +/* --- malware_*_defer --- */ +static inline int +malware_panic_defer(const uschar * str) +{ +log_write(0, LOG_MAIN|LOG_PANIC, "malware acl condition: %s", str); +return DEFER; +} +static inline int +malware_log_defer(const uschar * str) +{ +log_write(0, LOG_MAIN, "malware acl condition: %s", str); +return DEFER; +} +/* --- m_*_defer --- */ +static inline int +m_panic_defer(struct scan * scanent, const uschar * hostport, + const uschar * str) +{ +return malware_panic_defer(string_sprintf("%s %s : %s", + scanent->name, hostport ? hostport : CUS"", str)); +} +static inline int +m_log_defer(struct scan * scanent, const uschar * hostport, + const uschar * str) +{ +return malware_log_defer(string_sprintf("%s %s : %s", + scanent->name, hostport ? hostport : CUS"", str)); +} +/* --- m_*_defer_3 */ +static inline int +m_panic_defer_3(struct scan * scanent, const uschar * hostport, + const uschar * str, int fd_to_close) +{ +DEBUG(D_acl) debug_print_socket(fd_to_close); +(void) close(fd_to_close); +return m_panic_defer(scanent, hostport, str); +} + +/*************************************************/ + +#ifndef DISABLE_MAL_CLAM +/* Only used by the Clamav code, which is working from a list of servers and +uses the returned in_addr to get a second connection to the same system. +*/ +static inline int +m_tcpsocket(const uschar * hostname, unsigned int port, + host_item * host, uschar ** errstr, const blob * fastopen_blob) +{ +return ip_connectedsocket(SOCK_STREAM, hostname, port, port, 5, + host, errstr, fastopen_blob); +} +#endif + +static int +m_sock_send(int sock, uschar * buf, int cnt, uschar ** errstr) +{ +if (send(sock, buf, cnt, 0) < 0) + { + int err = errno; + (void)close(sock); + *errstr = string_sprintf("unable to send to socket (%s): %s", + buf, strerror(err)); + return -1; + } +return sock; +} + +static const pcre * +m_pcre_compile(const uschar * re, uschar ** errstr) +{ +const uschar * rerror; +int roffset; +const pcre * cre; + +if (!(cre = pcre_compile(CS re, PCRE_COPT, CCSS &rerror, &roffset, NULL))) + *errstr= string_sprintf("regular expression error in '%s': %s at offset %d", + re, rerror, roffset); +return cre; +} + +uschar * +m_pcre_exec(const pcre * cre, uschar * text) +{ +int ovector[10*3]; +int i = pcre_exec(cre, NULL, CS text, Ustrlen(text), 0, 0, + ovector, nelem(ovector)); +uschar * substr = NULL; +if (i >= 2) /* Got it */ + pcre_get_substring(CS text, ovector, i, 1, CCSS &substr); +return substr; +} + +static const pcre * +m_pcre_nextinlist(const uschar ** list, int * sep, + char * listerr, uschar ** errstr) +{ +const uschar * list_ele; +const pcre * cre = NULL; + +if (!(list_ele = string_nextinlist(list, sep, NULL, 0))) + *errstr = US listerr; +else + { + DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "RE: ", + string_printing(list_ele)); + cre = m_pcre_compile(CUS list_ele, errstr); + } +return cre; +} + + +/* + Simple though inefficient wrapper for reading a line. Drop CRs and the + trailing newline. Can return early on buffer full. Null-terminate. + Apply initial timeout if no data ready. + + Return: number of chars - zero for an empty line + -1 on EOF + -2 on timeout or error +*/ +static int +recv_line(int fd, uschar * buffer, int bsize, time_t tmo) +{ +uschar * p = buffer; +ssize_t rcv; +BOOL ok = FALSE; + +if (!fd_ready(fd, tmo)) + return -2; + +/*XXX tmo handling assumes we always get a whole line */ +/* read until \n */ +errno = 0; +while ((rcv = read(fd, p, 1)) > 0) + { + ok = TRUE; + if (p-buffer > bsize-2) break; + if (*p == '\n') break; + if (*p != '\r') p++; + } +if (!ok) + { + DEBUG(D_acl) + { + debug_printf_indent("Malware scan: read %s (%s)\n", + rcv==0 ? "EOF" : "error", strerror(errno)); + debug_print_socket(fd); + } + return rcv==0 ? -1 : -2; + } +*p = '\0'; + +DEBUG(D_acl) debug_printf_indent("Malware scan: read '%s'\n", buffer); +return p - buffer; +} + +/* return TRUE iff size as requested */ +static BOOL +recv_len(int sock, void * buf, int size, time_t tmo) +{ +return fd_ready(sock, tmo) + ? recv(sock, buf, size, 0) == size + : FALSE; +} + + + +#ifndef DISABLE_MAL_MKS +/* ============= private routines for the "mksd" scanner type ============== */ + +# include <sys/uio.h> + +static inline int +mksd_writev (int sock, struct iovec * iov, int iovcnt) +{ +int i; + +for (;;) + { + do + i = writev (sock, iov, iovcnt); + while (i < 0 && errno == EINTR); + if (i <= 0) + { + (void) malware_panic_defer( + US"unable to write to mksd UNIX socket (/var/run/mksd/socket)"); + return -1; + } + for (;;) /* check for short write */ + if (i >= iov->iov_len) + { + if (--iovcnt == 0) + return 0; + i -= iov->iov_len; + iov++; + } + else + { + iov->iov_len -= i; + iov->iov_base = CS iov->iov_base + i; + break; + } + } +} + +static inline int +mksd_read_lines (int sock, uschar *av_buffer, int av_buffer_size, time_t tmo) +{ +client_conn_ctx cctx = {.sock = sock}; +int offset = 0; +int i; + +do + { + i = ip_recv(&cctx, av_buffer+offset, av_buffer_size-offset, tmo); + if (i <= 0) + { + (void) malware_panic_defer(US"unable to read from mksd UNIX socket (/var/run/mksd/socket)"); + return -1; + } + + offset += i; + /* offset == av_buffer_size -> buffer full */ + if (offset == av_buffer_size) + { + (void) malware_panic_defer(US"malformed reply received from mksd"); + return -1; + } + } while (av_buffer[offset-1] != '\n'); + +av_buffer[offset] = '\0'; +return offset; +} + +static inline int +mksd_parse_line(struct scan * scanent, char * line) +{ +char *p; + +switch (*line) + { + case 'O': /* OK */ + return OK; + + case 'E': + case 'A': /* ERR */ + if ((p = strchr (line, '\n')) != NULL) + *p = '\0'; + return m_panic_defer(scanent, NULL, + string_sprintf("scanner failed: %s", line)); + + default: /* VIR */ + if ((p = strchr (line, '\n')) != NULL) + { + *p = '\0'; + if ( p-line > 5 + && line[3] == ' ' + && (p = strchr(line+4, ' ')) != NULL + && p-line > 4 + ) + { + *p = '\0'; + malware_name = string_copy(US line+4); + return OK; + } + } + return m_panic_defer(scanent, NULL, + string_sprintf("malformed reply received: %s", line)); + } +} + +static int +mksd_scan_packed(struct scan * scanent, int sock, const uschar * scan_filename, + time_t tmo) +{ +struct iovec iov[3]; +const char *cmd = "MSQ\n"; +uschar av_buffer[1024]; + +iov[0].iov_base = (void *) cmd; +iov[0].iov_len = 3; +iov[1].iov_base = (void *) scan_filename; +iov[1].iov_len = Ustrlen(scan_filename); +iov[2].iov_base = (void *) (cmd + 3); +iov[2].iov_len = 1; + +if (mksd_writev (sock, iov, 3) < 0) + return DEFER; + +if (mksd_read_lines (sock, av_buffer, sizeof (av_buffer), tmo) < 0) + return DEFER; + +return mksd_parse_line (scanent, CS av_buffer); +} +#endif /* MKSD */ + + +#ifndef DISABLE_MAL_CLAM +static int +clamd_option(clamd_address * cd, const uschar * optstr, int * subsep) +{ +uschar * s; + +cd->retry = 0; +while ((s = string_nextinlist(&optstr, subsep, NULL, 0))) + if (Ustrncmp(s, "retry=", 6) == 0) + { + int sec = readconf_readtime((s += 6), '\0', FALSE); + if (sec < 0) + return FAIL; + cd->retry = sec; + } + else + return FAIL; +return OK; +} +#endif + + + +/************************************************* +* Scan content for malware * +*************************************************/ + +/* This is an internal interface for scanning an email; the normal interface +is via malware(), or there's malware_in_file() used for testing/debugging. + +Arguments: + malware_re match condition for "malware=" + scan_filename the file holding the email to be scanned, if we're faking + this up for the -bmalware test, else NULL + timeout if nonzero, non-default timeoutl + +Returns: Exim message processing code (OK, FAIL, DEFER, ...) + where true means malware was found (condition applies) +*/ +static int +malware_internal(const uschar * malware_re, const uschar * scan_filename, + int timeout) +{ +int sep = 0; +const uschar *av_scanner_work = av_scanner; +uschar *scanner_name; +unsigned long mbox_size; +FILE *mbox_file; +const pcre *re; +uschar * errstr; +struct scan * scanent; +const uschar * scanner_options; +client_conn_ctx malware_daemon_ctx = {.sock = -1}; +time_t tmo; +uschar * eml_filename, * eml_dir; + +if (!malware_re) + return FAIL; /* empty means "don't match anything" */ + +/* Ensure the eml mbox file is spooled up */ + +if (!(mbox_file = spool_mbox(&mbox_size, scan_filename, &eml_filename))) + return malware_panic_defer(US"error while creating mbox spool file"); + +/* None of our current scanners need the mbox file as a stream (they use +the name), so we can close it right away. Get the directory too. */ + +(void) fclose(mbox_file); +eml_dir = string_copyn(eml_filename, Ustrrchr(eml_filename, '/') - eml_filename); + +/* parse 1st option */ +if (strcmpic(malware_re, US"false") == 0 || Ustrcmp(malware_re,"0") == 0) + return FAIL; /* explicitly no matching */ + +/* special cases (match anything except empty) */ +if ( strcmpic(malware_re,US"true") == 0 + || Ustrcmp(malware_re,"*") == 0 + || Ustrcmp(malware_re,"1") == 0 + ) + { + if ( !malware_default_re + && !(malware_default_re = m_pcre_compile(malware_regex_default, &errstr))) + return malware_panic_defer(errstr); + malware_re = malware_regex_default; + re = malware_default_re; + } + +/* compile the regex, see if it works */ +else if (!(re = m_pcre_compile(malware_re, &errstr))) + return malware_panic_defer(errstr); + +/* if av_scanner starts with a dollar, expand it first */ +if (*av_scanner == '$') + { + if (!(av_scanner_work = expand_string(av_scanner))) + return malware_panic_defer( + string_sprintf("av_scanner starts with $, but expansion failed: %s", + expand_string_message)); + + DEBUG(D_acl) + debug_printf_indent("Expanded av_scanner global: %s\n", av_scanner_work); + /* disable result caching in this case */ + malware_name = NULL; + malware_ok = FALSE; + } + +/* Do not scan twice (unless av_scanner is dynamic). */ +if (!malware_ok) + { + /* find the scanner type from the av_scanner option */ + if (!(scanner_name = string_nextinlist(&av_scanner_work, &sep, NULL, 0))) + return malware_panic_defer(US"av_scanner configuration variable is empty"); + if (!timeout) timeout = MALWARE_TIMEOUT; + tmo = time(NULL) + timeout; + + for (scanent = m_scans; ; scanent++) + { + if (!scanent->name) + return malware_panic_defer(string_sprintf("unknown scanner type '%s'", + scanner_name)); + if (strcmpic(scanner_name, US scanent->name) != 0) + continue; + DEBUG(D_acl) debug_printf_indent("Malware scan: %s tmo=%s\n", + scanner_name, readconf_printtime(timeout)); + + if (!(scanner_options = string_nextinlist(&av_scanner_work, &sep, NULL, 0))) + scanner_options = scanent->options_default; + if (scanent->conn == MC_NONE) + break; + + DEBUG(D_acl) debug_printf_indent("%15s%10s%s\n", "", "socket: ", scanner_options); + switch(scanent->conn) + { + case MC_TCP: + malware_daemon_ctx.sock = ip_tcpsocket(scanner_options, &errstr, 5, NULL); break; + case MC_UNIX: + malware_daemon_ctx.sock = ip_unixsocket(scanner_options, &errstr); break; + case MC_STRM: + malware_daemon_ctx.sock = ip_streamsocket(scanner_options, &errstr, 5, NULL); break; + default: + /* compiler quietening */ break; + } + if (malware_daemon_ctx.sock < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + break; + } + + switch (scanent->scancode) + { +#ifndef DISABLE_MAL_FFROTD + case M_FPROTD: /* "f-protd" scanner type -------------------------------- */ + { + uschar *fp_scan_option; + unsigned int detected=0, par_count=0; + uschar * scanrequest; + uschar buf[32768], *strhelper, *strhelper2; + uschar * malware_name_internal = NULL; + int len; + + scanrequest = string_sprintf("GET %s", eml_filename); + + while ((fp_scan_option = string_nextinlist(&av_scanner_work, &sep, + NULL, 0))) + { + scanrequest = string_sprintf("%s%s%s", scanrequest, + par_count ? "%20" : "?", fp_scan_option); + par_count++; + } + scanrequest = string_sprintf("%s HTTP/1.0\r\n\r\n", scanrequest); + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n", + scanner_name, scanrequest); + + /* send scan request */ + if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + while ((len = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) >= 0) + if (len > 0) + { + if (Ustrstr(buf, US"<detected type=\"") != NULL) + detected = 1; + else if (detected && (strhelper = Ustrstr(buf, US"<name>"))) + { + if ((strhelper2 = Ustrstr(buf, US"</name>")) != NULL) + { + *strhelper2 = '\0'; + malware_name_internal = string_copy(strhelper+6); + } + } + else if (Ustrstr(buf, US"<summary code=\"")) + { + malware_name = Ustrstr(buf, US"<summary code=\"11\">") + ? malware_name_internal : NULL; + break; + } + } + if (len < -1) + { + (void)close(malware_daemon_ctx.sock); + return DEFER; + } + break; + } /* f-protd */ +#endif + +#ifndef DISABLE_MAL_FFROT6D + case M_FPROT6D: /* "f-prot6d" scanner type ----------------------------------- */ + { + int bread; + uschar * e; + uschar * linebuffer; + uschar * scanrequest; + uschar av_buffer[1024]; + + if ((!fprot6d_re_virus && !(fprot6d_re_virus = m_pcre_compile(fprot6d_re_virus_str, &errstr))) + || (!fprot6d_re_error && !(fprot6d_re_error = m_pcre_compile(fprot6d_re_error_str, &errstr)))) + return malware_panic_defer(errstr); + + scanrequest = string_sprintf("SCAN FILE %s\n", eml_filename); + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n", + scanner_name, scanrequest); + + if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest), &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo); + + if (bread <= 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to read from socket (%s)", strerror(errno)), + malware_daemon_ctx.sock); + + if (bread == sizeof(av_buffer)) + return m_panic_defer_3(scanent, CUS callout_address, + US"buffer too small", malware_daemon_ctx.sock); + + av_buffer[bread] = '\0'; + linebuffer = string_copy(av_buffer); + + m_sock_send(malware_daemon_ctx.sock, US"QUIT\n", 5, 0); + + if ((e = m_pcre_exec(fprot6d_re_error, linebuffer))) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("scanner reported error (%s)", e), malware_daemon_ctx.sock); + + if (!(malware_name = m_pcre_exec(fprot6d_re_virus, linebuffer))) + malware_name = NULL; + + break; + } /* f-prot6d */ +#endif + +#ifndef DISABLE_MAL_DRWEB + case M_DRWEB: /* "drweb" scanner type ----------------------------------- */ + /* v0.1 - added support for tcp sockets */ + /* v0.0 - initial release -- support for unix sockets */ + { + int result; + off_t fsize; + unsigned int fsize_uint; + uschar * tmpbuf, *drweb_fbuf; + int drweb_rc, drweb_cmd, drweb_flags = 0x0000, drweb_fd, + drweb_vnum, drweb_slen, drweb_fin = 0x0000; + + /* prepare variables */ + drweb_cmd = htonl(DRWEBD_SCAN_CMD); + drweb_flags = htonl(DRWEBD_RETURN_VIRUSES | DRWEBD_IS_MAIL); + + if (*scanner_options != '/') + { + /* calc file size */ + if ((drweb_fd = exim_open2(CCS eml_filename, O_RDONLY)) == -1) + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't open spool file %s: %s", + eml_filename, strerror(errno)), + malware_daemon_ctx.sock); + + if ((fsize = lseek(drweb_fd, 0, SEEK_END)) == -1) + { + int err; +badseek: err = errno; + (void)close(drweb_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't seek spool file %s: %s", + eml_filename, strerror(err)), + malware_daemon_ctx.sock); + } + fsize_uint = (unsigned int) fsize; + if ((off_t)fsize_uint != fsize) + { + (void)close(drweb_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("seeking spool file %s, size overflow", + eml_filename), + malware_daemon_ctx.sock); + } + drweb_slen = htonl(fsize); + if (lseek(drweb_fd, 0, SEEK_SET) < 0) + goto badseek; + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s remote scan [%s]\n", + scanner_name, scanner_options); + + /* send scan request */ + if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0)) + { + (void)close(drweb_fd); + return m_panic_defer_3(scanent, CUS callout_address, string_sprintf( + "unable to send commands to socket (%s)", scanner_options), + malware_daemon_ctx.sock); + } + + if (!(drweb_fbuf = store_malloc(fsize_uint))) + { + (void)close(drweb_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("unable to allocate memory %u for file (%s)", + fsize_uint, eml_filename), + malware_daemon_ctx.sock); + } + + if ((result = read (drweb_fd, drweb_fbuf, fsize)) == -1) + { + int err = errno; + (void)close(drweb_fd); + store_free(drweb_fbuf); + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't read spool file %s: %s", + eml_filename, strerror(err)), + malware_daemon_ctx.sock); + } + (void)close(drweb_fd); + + /* send file body to socket */ + if (send(malware_daemon_ctx.sock, drweb_fbuf, fsize, 0) < 0) + { + store_free(drweb_fbuf); + return m_panic_defer_3(scanent, CUS callout_address, string_sprintf( + "unable to send file body to socket (%s)", scanner_options), + malware_daemon_ctx.sock); + } + store_free(drweb_fbuf); + } + else + { + drweb_slen = htonl(Ustrlen(eml_filename)); + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s local scan [%s]\n", + scanner_name, scanner_options); + + /* send scan request */ + if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0) || + (send(malware_daemon_ctx.sock, eml_filename, Ustrlen(eml_filename), 0) < 0) || + (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0)) + return m_panic_defer_3(scanent, CUS callout_address, string_sprintf( + "unable to send commands to socket (%s)", scanner_options), + malware_daemon_ctx.sock); + } + + /* wait for result */ + if (!recv_len(malware_daemon_ctx.sock, &drweb_rc, sizeof(drweb_rc), tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"unable to read return code", malware_daemon_ctx.sock); + drweb_rc = ntohl(drweb_rc); + + if (!recv_len(malware_daemon_ctx.sock, &drweb_vnum, sizeof(drweb_vnum), tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"unable to read the number of viruses", malware_daemon_ctx.sock); + drweb_vnum = ntohl(drweb_vnum); + + /* "virus(es) found" if virus number is > 0 */ + if (drweb_vnum) + { + gstring * g = NULL; + + /* setup default virus name */ + malware_name = US"unknown"; + + /* set up match regex */ + if (!drweb_re) + drweb_re = m_pcre_compile(drweb_re_str, &errstr); + + /* read and concatenate virus names into one string */ + for (int i = 0; i < drweb_vnum; i++) + { + int ovector[10*3]; + + /* read the size of report */ + if (!recv_len(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"cannot read report size", malware_daemon_ctx.sock); + drweb_slen = ntohl(drweb_slen); + + /* assume tainted, since it is external input */ + tmpbuf = store_get(drweb_slen, TRUE); + + /* read report body */ + if (!recv_len(malware_daemon_ctx.sock, tmpbuf, drweb_slen, tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"cannot read report string", malware_daemon_ctx.sock); + tmpbuf[drweb_slen] = '\0'; + + /* try matcher on the line, grab substring */ + result = pcre_exec(drweb_re, NULL, CS tmpbuf, Ustrlen(tmpbuf), 0, 0, + ovector, nelem(ovector)); + if (result >= 2) + { + const char * pre_malware_nb; + + pcre_get_substring(CS tmpbuf, ovector, result, 1, &pre_malware_nb); + + if (i==0) /* the first name we just copy to malware_name */ + g = string_cat(NULL, US pre_malware_nb); + + /*XXX could be string_append_listele? */ + else /* concatenate each new virus name to previous */ + g = string_append(g, 2, "/", pre_malware_nb); + + pcre_free_substring(pre_malware_nb); + } + } + malware_name = string_from_gstring(g); + } + else + { + const char *drweb_s = NULL; + + if (drweb_rc & DERR_READ_ERR) drweb_s = "read error"; + if (drweb_rc & DERR_NOMEMORY) drweb_s = "no memory"; + if (drweb_rc & DERR_TIMEOUT) drweb_s = "timeout"; + if (drweb_rc & DERR_BAD_CALL) drweb_s = "wrong command"; + /* retcodes DERR_SYMLINK, DERR_NO_REGFILE, DERR_SKIPPED. + * DERR_TOO_BIG, DERR_TOO_COMPRESSED, DERR_SPAM, + * DERR_CRC_ERROR, DERR_READSOCKET, DERR_WRITE_ERR + * and others are ignored */ + if (drweb_s) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("drweb daemon retcode 0x%x (%s)", drweb_rc, drweb_s), + malware_daemon_ctx.sock); + + /* no virus found */ + malware_name = NULL; + } + break; + } /* drweb */ +#endif + +#ifndef DISABLE_MAL_AVE + case M_AVES: /* "aveserver" scanner type -------------------------------- */ + { + uschar buf[32768]; + int result; + + /* read aveserver's greeting and see if it is ready (2xx greeting) */ + buf[0] = 0; + recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo); + + if (buf[0] != '2') /* aveserver is having problems */ + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unavailable (Responded: %s).", + ((buf[0] != 0) ? buf : US "nothing") ), + malware_daemon_ctx.sock); + + /* prepare our command */ + (void)string_format(buf, sizeof(buf), "SCAN bPQRSTUW %s\r\n", + eml_filename); + + /* and send it */ + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s %s\n", + scanner_name, buf); + if (m_sock_send(malware_daemon_ctx.sock, buf, Ustrlen(buf), &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + malware_name = NULL; + result = 0; + /* read response lines, find malware name and final response */ + while (recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo) > 0) + { + if (buf[0] == '2') + break; + if (buf[0] == '5') /* aveserver is having problems */ + { + result = m_panic_defer(scanent, CUS callout_address, + string_sprintf("unable to scan file %s (Responded: %s).", + eml_filename, buf)); + break; + } + if (Ustrncmp(buf,"322",3) == 0) + { + uschar *p = Ustrchr(&buf[4], ' '); + *p = '\0'; + malware_name = string_copy(&buf[4]); + } + } + + if (m_sock_send(malware_daemon_ctx.sock, US"quit\r\n", 6, &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + /* read aveserver's greeting and see if it is ready (2xx greeting) */ + buf[0] = 0; + recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo); + + if (buf[0] != '2') /* aveserver is having problems */ + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to quit dialogue (Responded: %s).", + ((buf[0] != 0) ? buf : US "nothing") ), + malware_daemon_ctx.sock); + + if (result == DEFER) + { + (void)close(malware_daemon_ctx.sock); + return DEFER; + } + break; + } /* aveserver */ +#endif + +#ifndef DISABLE_MAL_FSECURE + case M_FSEC: /* "fsecure" scanner type ---------------------------------- */ + { + int i, bread = 0; + uschar * file_name; + uschar av_buffer[1024]; + static uschar *cmdopt[] = { US"CONFIGURE\tARCHIVE\t1\n", + US"CONFIGURE\tTIMEOUT\t0\n", + US"CONFIGURE\tMAXARCH\t5\n", + US"CONFIGURE\tMIME\t1\n" }; + + malware_name = NULL; + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n", + scanner_name, scanner_options); + /* pass options */ + memset(av_buffer, 0, sizeof(av_buffer)); + for (i = 0; i != nelem(cmdopt); i++) + { + + if (m_sock_send(malware_daemon_ctx.sock, cmdopt[i], Ustrlen(cmdopt[i]), &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo); + if (bread > 0) av_buffer[bread]='\0'; + if (bread < 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to read answer %d (%s)", i, strerror(errno)), + malware_daemon_ctx.sock); + for (int j = 0; j < bread; j++) + if (av_buffer[j] == '\r' || av_buffer[j] == '\n') + av_buffer[j] ='@'; + } + + /* pass the mailfile to fsecure */ + file_name = string_sprintf("SCAN\t%s\n", eml_filename); + + if (m_sock_send(malware_daemon_ctx.sock, file_name, Ustrlen(file_name), &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + /* set up match */ + /* todo also SUSPICION\t */ + if (!fsec_re) + fsec_re = m_pcre_compile(fsec_re_str, &errstr); + + /* read report, linewise. Apply a timeout as the Fsecure daemon + sometimes wants an answer to "PING" but they won't tell us what */ + { + uschar * p = av_buffer; + uschar * q; + + for (;;) + { + errno = ETIMEDOUT; + i = av_buffer+sizeof(av_buffer)-p; + if ((bread= ip_recv(&malware_daemon_ctx, p, i-1, tmo)) < 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to read result (%s)", strerror(errno)), + malware_daemon_ctx.sock); + + for (p[bread] = '\0'; (q = Ustrchr(p, '\n')); p = q+1) + { + *q = '\0'; + + /* Really search for virus again? */ + if (!malware_name) + /* try matcher on the line, grab substring */ + malware_name = m_pcre_exec(fsec_re, p); + + if (Ustrstr(p, "OK\tScan ok.")) + goto fsec_found; + } + + /* copy down the trailing partial line then read another chunk */ + i = av_buffer+sizeof(av_buffer)-p; + memmove(av_buffer, p, i); + p = av_buffer+i; + } + } + + fsec_found: + break; + } /* fsecure */ +#endif + +#ifndef DISABLE_MAL_KAV + case M_KAVD: /* "kavdaemon" scanner type -------------------------------- */ + { + time_t t; + uschar tmpbuf[1024]; + uschar * scanrequest; + int kav_rc; + unsigned long kav_reportlen; + int bread; + const pcre *kav_re; + uschar *p; + + /* get current date and time, build scan request */ + time(&t); + /* pdp note: before the eml_filename parameter, this scanned the + directory; not finding documentation, so we'll strip off the directory. + The side-effect is that the test framework scanning may end up in + scanning more than was requested, but for the normal interface, this is + fine. */ + + strftime(CS tmpbuf, sizeof(tmpbuf), "%d %b %H:%M:%S", localtime(&t)); + scanrequest = string_sprintf("<0>%s:%s", CS tmpbuf, eml_filename); + p = Ustrrchr(scanrequest, '/'); + if (p) + *p = '\0'; + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n", + scanner_name, scanner_options); + + /* send scan request */ + if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + /* wait for result */ + if (!recv_len(malware_daemon_ctx.sock, tmpbuf, 2, tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"unable to read 2 bytes from socket.", malware_daemon_ctx.sock); + + /* get errorcode from one nibble */ + kav_rc = tmpbuf[ test_byte_order()==LITTLE_MY_ENDIAN ? 0 : 1 ] & 0x0F; + switch(kav_rc) + { + case 5: case 6: /* improper kavdaemon configuration */ + return m_panic_defer_3(scanent, CUS callout_address, + US"please reconfigure kavdaemon to NOT disinfect or remove infected files.", + malware_daemon_ctx.sock); + case 1: + return m_panic_defer_3(scanent, CUS callout_address, + US"reported 'scanning not completed' (code 1).", malware_daemon_ctx.sock); + case 7: + return m_panic_defer_3(scanent, CUS callout_address, + US"reported 'kavdaemon damaged' (code 7).", malware_daemon_ctx.sock); + } + + /* code 8 is not handled, since it is ambiguous. It appears mostly on + bounces where part of a file has been cut off */ + + /* "virus found" return codes (2-4) */ + if (kav_rc > 1 && kav_rc < 5) + { + int report_flag = 0; + + /* setup default virus name */ + malware_name = US"unknown"; + + report_flag = tmpbuf[ test_byte_order() == LITTLE_MY_ENDIAN ? 1 : 0 ]; + + /* read the report, if available */ + if (report_flag == 1) + { + /* read report size */ + if (!recv_len(malware_daemon_ctx.sock, &kav_reportlen, 4, tmo)) + return m_panic_defer_3(scanent, CUS callout_address, + US"cannot read report size", malware_daemon_ctx.sock); + + /* it's possible that avp returns av_buffer[1] == 1 but the + reportsize is 0 (!?) */ + if (kav_reportlen > 0) + { + /* set up match regex, depends on retcode */ + if (kav_rc == 3) + { + if (!kav_re_sus) kav_re_sus = m_pcre_compile(kav_re_sus_str, &errstr); + kav_re = kav_re_sus; + } + else + { + if (!kav_re_inf) kav_re_inf = m_pcre_compile(kav_re_inf_str, &errstr); + kav_re = kav_re_inf; + } + + /* read report, linewise. Using size from stream to read amount of data + from same stream is safe enough. */ + /* coverity[tainted_data] */ + while (kav_reportlen > 0) + { + if ((bread = recv_line(malware_daemon_ctx.sock, tmpbuf, sizeof(tmpbuf), tmo)) < 0) + break; + kav_reportlen -= bread+1; + + /* try matcher on the line, grab substring */ + if ((malware_name = m_pcre_exec(kav_re, tmpbuf))) + break; + } + } + } + } + else /* no virus found */ + malware_name = NULL; + + break; + } +#endif + +#ifndef DISABLE_MAL_CMDLINE + case M_CMDL: /* "cmdline" scanner type ---------------------------------- */ + { + const uschar *cmdline_scanner = scanner_options; + const pcre *cmdline_trigger_re; + const pcre *cmdline_regex_re; + uschar * file_name; + uschar * commandline; + void (*eximsigchld)(int); + void (*eximsigpipe)(int); + FILE *scanner_out = NULL; + int scanner_fd; + FILE *scanner_record = NULL; + uschar linebuffer[32767]; + int rcnt; + int trigger = 0; + uschar *p; + + if (!cmdline_scanner) + return m_panic_defer(scanent, NULL, errstr); + + /* find scanner output trigger */ + cmdline_trigger_re = m_pcre_nextinlist(&av_scanner_work, &sep, + "missing trigger specification", &errstr); + if (!cmdline_trigger_re) + return m_panic_defer(scanent, NULL, errstr); + + /* find scanner name regex */ + cmdline_regex_re = m_pcre_nextinlist(&av_scanner_work, &sep, + "missing virus name regex specification", &errstr); + if (!cmdline_regex_re) + return m_panic_defer(scanent, NULL, errstr); + + /* prepare scanner call; despite the naming, file_name holds a directory + name which is documented as the value given to %s. */ + + file_name = string_copy(eml_filename); + p = Ustrrchr(file_name, '/'); + if (p) + *p = '\0'; + commandline = string_sprintf(CS cmdline_scanner, file_name); + + /* redirect STDERR too */ + commandline = string_sprintf("%s 2>&1", commandline); + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n", + scanner_name, commandline); + + /* store exims signal handlers */ + eximsigchld = signal(SIGCHLD,SIG_DFL); + eximsigpipe = signal(SIGPIPE,SIG_DFL); + + if (!(scanner_out = popen(CS commandline,"r"))) + { + int err = errno; + signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe); + return m_panic_defer(scanent, NULL, + string_sprintf("call (%s) failed: %s.", commandline, strerror(err))); + } + scanner_fd = fileno(scanner_out); + + file_name = string_sprintf("%s/%s_scanner_output", eml_dir, message_id); + + if (!(scanner_record = modefopen(file_name, "wb", SPOOL_MODE))) + { + int err = errno; + (void) pclose(scanner_out); + signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe); + return m_panic_defer(scanent, NULL, string_sprintf( + "opening scanner output file (%s) failed: %s.", + file_name, strerror(err))); + } + + /* look for trigger while recording output */ + while ((rcnt = recv_line(scanner_fd, linebuffer, + sizeof(linebuffer), tmo))) + { + if (rcnt < 0) + { + int err = errno; + if (rcnt == -1) + break; + (void) pclose(scanner_out); + signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe); + return m_panic_defer(scanent, NULL, string_sprintf( + "unable to read from scanner (%s): %s", + commandline, strerror(err))); + } + + if (Ustrlen(linebuffer) > fwrite(linebuffer, 1, Ustrlen(linebuffer), scanner_record)) + { + /* short write */ + (void) pclose(scanner_out); + signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe); + return m_panic_defer(scanent, NULL, string_sprintf( + "short write on scanner output file (%s).", file_name)); + } + putc('\n', scanner_record); + /* try trigger match */ + if ( !trigger + && regex_match_and_setup(cmdline_trigger_re, linebuffer, 0, -1) + ) + trigger = 1; + } + + (void)fclose(scanner_record); + sep = pclose(scanner_out); + signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe); + if (sep != 0) + return m_panic_defer(scanent, NULL, + sep == -1 + ? string_sprintf("running scanner failed: %s", strerror(sep)) + : string_sprintf("scanner returned error code: %d", sep)); + + if (trigger) + { + uschar * s; + /* setup default virus name */ + malware_name = US"unknown"; + + /* re-open the scanner output file, look for name match */ + scanner_record = Ufopen(file_name, "rb"); + while (Ufgets(linebuffer, sizeof(linebuffer), scanner_record)) + if ((s = m_pcre_exec(cmdline_regex_re, linebuffer))) /* try match */ + malware_name = s; + (void)fclose(scanner_record); + } + else /* no virus found */ + malware_name = NULL; + break; + } /* cmdline */ +#endif + +#ifndef DISABLE_MAL_SOPHIE + case M_SOPHIE: /* "sophie" scanner type --------------------------------- */ + { + int bread = 0; + uschar *p; + uschar * file_name; + uschar av_buffer[1024]; + + /* pass the scan directory to sophie */ + file_name = string_copy(eml_filename); + if ((p = Ustrrchr(file_name, '/'))) + *p = '\0'; + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n", + scanner_name, scanner_options); + + if ( write(malware_daemon_ctx.sock, file_name, Ustrlen(file_name)) < 0 + || write(malware_daemon_ctx.sock, "\n", 1) != 1 + ) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to write to UNIX socket (%s)", scanner_options), + malware_daemon_ctx.sock); + + /* wait for result */ + memset(av_buffer, 0, sizeof(av_buffer)); + if ((bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo)) <= 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to read from UNIX socket (%s)", scanner_options), + malware_daemon_ctx.sock); + + /* infected ? */ + if (av_buffer[0] == '1') { + uschar * s = Ustrchr(av_buffer, '\n'); + if (s) + *s = '\0'; + malware_name = string_copy(&av_buffer[2]); + } + else if (!strncmp(CS av_buffer, "-1", 2)) + return m_panic_defer_3(scanent, CUS callout_address, + US"scanner reported error", malware_daemon_ctx.sock); + else /* all ok, no virus */ + malware_name = NULL; + + break; + } +#endif + +#ifndef DISABLE_MAL_CLAM + case M_CLAMD: /* "clamd" scanner type ----------------------------------- */ + { +/* This code was originally contributed by David Saez */ +/* There are three scanning methods available to us: +* (1) Use the SCAN command, pointing to a file in the filesystem +* (2) Use the STREAM command, send the data on a separate port +* (3) Use the zINSTREAM command, send the data inline +* The zINSTREAM command was introduced with ClamAV 0.95, which marked +* STREAM deprecated; see: http://wiki.clamav.net/bin/view/Main/UpgradeNotes095 +* In Exim, we use SCAN if using a Unix-domain socket or explicitly told that +* the TCP-connected daemon is actually local; otherwise we use zINSTREAM +* See Exim bug 926 for details. */ + + uschar *p, *vname, *result_tag; + int bread=0; + uschar av_buffer[1024]; + uschar *hostname = US""; + host_item connhost; + uschar *clamav_fbuf; + int clam_fd, result; + off_t fsize; + unsigned int fsize_uint; + BOOL use_scan_command = FALSE; + clamd_address * cv[MAX_CLAMD_SERVERS]; + int num_servers = 0; + uint32_t send_size, send_final_zeroblock; + blob cmd_str; + + /*XXX if unixdomain socket, only one server supported. Needs fixing; + there's no reason we should not mix local and remote servers */ + + if (*scanner_options == '/') + { + clamd_address * cd; + const uschar * sublist; + int subsep = ' '; + + /* Local file; so we def want to use_scan_command and don't want to try + * passing IP/port combinations */ + use_scan_command = TRUE; + cd = (clamd_address *) store_get(sizeof(clamd_address), FALSE); + + /* extract socket-path part */ + sublist = scanner_options; + cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0); + + /* parse options */ + if (clamd_option(cd, sublist, &subsep) != OK) + return m_panic_defer(scanent, NULL, + string_sprintf("bad option '%s'", scanner_options)); + cv[0] = cd; + } + else + { + /* Go through the rest of the list of host/port and construct an array + * of servers to try. The first one is the bit we just passed from + * scanner_options so process that first and then scan the remainder of + * the address buffer */ + do + { + clamd_address * cd; + const uschar * sublist; + int subsep = ' '; + uschar * s; + + /* The 'local' option means use the SCAN command over the network + * socket (ie common file storage in use) */ + /*XXX we could accept this also as a local option? */ + if (strcmpic(scanner_options, US"local") == 0) + { + use_scan_command = TRUE; + continue; + } + + cd = (clamd_address *) store_get(sizeof(clamd_address), FALSE); + + /* extract host and port part */ + sublist = scanner_options; + if (!(cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0))) + { + (void) m_panic_defer(scanent, NULL, + string_sprintf("missing address: '%s'", scanner_options)); + continue; + } + if (!(s = string_nextinlist(&sublist, &subsep, NULL, 0))) + { + (void) m_panic_defer(scanent, NULL, + string_sprintf("missing port: '%s'", scanner_options)); + continue; + } + cd->tcp_port = atoi(CS s); + + /* parse options */ + /*XXX should these options be common over scanner types? */ + if (clamd_option(cd, sublist, &subsep) != OK) + return m_panic_defer(scanent, NULL, + string_sprintf("bad option '%s'", scanner_options)); + + cv[num_servers++] = cd; + if (num_servers >= MAX_CLAMD_SERVERS) + { + (void) m_panic_defer(scanent, NULL, + US"More than " MAX_CLAMD_SERVERS_S " clamd servers " + "specified; only using the first " MAX_CLAMD_SERVERS_S ); + break; + } + } while ((scanner_options = string_nextinlist(&av_scanner_work, &sep, + NULL, 0))); + + /* check if we have at least one server */ + if (!num_servers) + return m_panic_defer(scanent, NULL, + US"no useable server addresses in malware configuration option."); + } + + /* See the discussion of response formats below to see why we really + don't like colons in filenames when passing filenames to ClamAV. */ + if (use_scan_command && Ustrchr(eml_filename, ':')) + return m_panic_defer(scanent, NULL, + string_sprintf("local/SCAN mode incompatible with" \ + " : in path to email filename [%s]", eml_filename)); + + /* Set up the very first data we will be sending */ + if (!use_scan_command) + { cmd_str.data = US"zINSTREAM"; cmd_str.len = 10; } + else + { + cmd_str.data = string_sprintf("SCAN %s\n", eml_filename); + cmd_str.len = Ustrlen(cmd_str.data); + } + + /* We have some network servers specified */ + if (num_servers) + { + /* Confirmed in ClamAV source (0.95.3) that the TCPAddr option of clamd + * only supports AF_INET, but we should probably be looking to the + * future and rewriting this to be protocol-independent anyway. */ + + while (num_servers > 0) + { + int i = random_number(num_servers); + clamd_address * cd = cv[i]; + + DEBUG(D_acl) debug_printf_indent("trying server name %s, port %u\n", + cd->hostspec, cd->tcp_port); + + /* Lookup the host. This is to ensure that we connect to the same IP + * on both connections (as one host could resolve to multiple ips) */ + for (;;) + { + /*XXX we trust that the cmd_str is ideempotent */ + if ((malware_daemon_ctx.sock = m_tcpsocket(cd->hostspec, cd->tcp_port, + &connhost, &errstr, &cmd_str)) >= 0) + { + /* Connection successfully established with a server */ + hostname = cd->hostspec; + cmd_str.len = 0; + break; + } + if (cd->retry <= 0) break; + while (cd->retry > 0) cd->retry = sleep(cd->retry); + } + if (malware_daemon_ctx.sock >= 0) + break; + + (void) m_panic_defer(scanent, CUS callout_address, errstr); + + /* Remove the server from the list. XXX We should free the memory */ + num_servers--; + for (; i < num_servers; i++) + cv[i] = cv[i+1]; + } + + if (num_servers == 0) + return m_panic_defer(scanent, NULL, US"all servers failed"); + } + else + for (;;) + { + if ((malware_daemon_ctx.sock = ip_unixsocket(cv[0]->hostspec, &errstr)) >= 0) + { + hostname = cv[0]->hostspec; + break; + } + if (cv[0]->retry <= 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + while (cv[0]->retry > 0) cv[0]->retry = sleep(cv[0]->retry); + } + + /* have socket in variable "sock"; command to use is semi-independent of + * the socket protocol. We use SCAN if is local (either Unix/local + * domain socket, or explicitly told local) else we stream the data. + * How we stream the data depends upon how we were built. */ + + if (!use_scan_command) + { + /* New protocol: "zINSTREAM\n" followed by a sequence of <length><data> + chunks, <n> a 4-byte number (network order), terminated by a zero-length + chunk. */ + + DEBUG(D_acl) debug_printf_indent( + "Malware scan: issuing %s new-style remote scan (zINSTREAM)\n", + scanner_name); + + /* Pass the string to ClamAV (10 = "zINSTREAM\0"), if not already sent */ + if (cmd_str.len) + if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0) + return m_panic_defer_3(scanent, CUS hostname, + string_sprintf("unable to send zINSTREAM to socket (%s)", + strerror(errno)), + malware_daemon_ctx.sock); + + /* calc file size */ + if ((clam_fd = exim_open2(CS eml_filename, O_RDONLY)) < 0) + { + int err = errno; + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't open spool file %s: %s", + eml_filename, strerror(err)), + malware_daemon_ctx.sock); + } + if ((fsize = lseek(clam_fd, 0, SEEK_END)) < 0) + { + int err; +b_seek: err = errno; + (void)close(clam_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't seek spool file %s: %s", + eml_filename, strerror(err)), + malware_daemon_ctx.sock); + } + fsize_uint = (unsigned int) fsize; + if ((off_t)fsize_uint != fsize) + { + (void)close(clam_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("seeking spool file %s, size overflow", + eml_filename), + malware_daemon_ctx.sock); + } + if (lseek(clam_fd, 0, SEEK_SET) < 0) + goto b_seek; + + if (!(clamav_fbuf = store_malloc(fsize_uint))) + { + (void)close(clam_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("unable to allocate memory %u for file (%s)", + fsize_uint, eml_filename), + malware_daemon_ctx.sock); + } + + if ((result = read(clam_fd, clamav_fbuf, fsize_uint)) < 0) + { + int err = errno; + store_free(clamav_fbuf); (void)close(clam_fd); + return m_panic_defer_3(scanent, NULL, + string_sprintf("can't read spool file %s: %s", + eml_filename, strerror(err)), + malware_daemon_ctx.sock); + } + (void)close(clam_fd); + + /* send file body to socket */ + send_size = htonl(fsize_uint); + send_final_zeroblock = 0; + if ((send(malware_daemon_ctx.sock, &send_size, sizeof(send_size), 0) < 0) || + (send(malware_daemon_ctx.sock, clamav_fbuf, fsize_uint, 0) < 0) || + (send(malware_daemon_ctx.sock, &send_final_zeroblock, sizeof(send_final_zeroblock), 0) < 0)) + { + store_free(clamav_fbuf); + return m_panic_defer_3(scanent, NULL, + string_sprintf("unable to send file body to socket (%s)", hostname), + malware_daemon_ctx.sock); + } + store_free(clamav_fbuf); + } + else + { /* use scan command */ + /* Send a SCAN command pointing to a filename; then in the then in the + * scan-method-neutral part, read the response back */ + +/* ================================================================= */ + + /* Prior to the reworking post-Exim-4.72, this scanned a directory, + which dates to when ClamAV needed us to break apart the email into the + MIME parts (eg, with the now deprecated demime condition coming first). + Some time back, ClamAV gained the ability to deconstruct the emails, so + doing this would actually have resulted in the mail attachments being + scanned twice, in the broken out files and from the original .eml. + Since ClamAV now handles emails (and has for quite some time) we can + just use the email file itself. */ + /* Pass the string to ClamAV (7 = "SCAN \n" + \0), if not already sent */ + + DEBUG(D_acl) debug_printf_indent( + "Malware scan: issuing %s local-path scan [%s]\n", + scanner_name, scanner_options); + + if (cmd_str.len) + if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to write to socket (%s)", strerror(errno)), + malware_daemon_ctx.sock); + + /* Do not shut down the socket for writing; a user report noted that + * clamd 0.70 does not react well to this. */ + } + /* Commands have been sent, no matter which scan method or connection + * type we're using; now just read the result, independent of method. */ + + /* Read the result */ + memset(av_buffer, 0, sizeof(av_buffer)); + bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo); + (void)close(malware_daemon_ctx.sock); + malware_daemon_ctx.sock = -1; + malware_daemon_ctx.tls_ctx = NULL; + + if (bread <= 0) + return m_panic_defer(scanent, CUS callout_address, + string_sprintf("unable to read from socket (%s)", + errno == 0 ? "EOF" : strerror(errno))); + + if (bread == sizeof(av_buffer)) + return m_panic_defer(scanent, CUS callout_address, + US"buffer too small"); + /* We're now assured of a NULL at the end of av_buffer */ + + /* Check the result. ClamAV returns one of two result formats. + In the basic mode, the response is of the form: + infected: -> "<filename>: <virusname> FOUND" + not-infected: -> "<filename>: OK" + error: -> "<filename>: <errcode> ERROR + If the ExtendedDetectionInfo option has been turned on, then we get: + "<filename>: <virusname>(<virushash>:<virussize>) FOUND" + for the infected case. Compare: +/tmp/eicar.com: Eicar-Test-Signature FOUND +/tmp/eicar.com: Eicar-Test-Signature(44d88612fea8a8f36de82e1278abb02f:68) FOUND + + In the streaming case, clamd uses the filename "stream" which you should + be able to verify with { ktrace clamdscan --stream /tmp/eicar.com }. (The + client app will replace "stream" with the original filename before returning + results to stdout, but the trace shows the data). + + We will assume that the pathname passed to clamd from Exim does not contain + a colon. We will have whined loudly above if the eml_filename does (and we're + passing a filename to clamd). */ + + if (!(*av_buffer)) + return m_panic_defer(scanent, CUS callout_address, + US"ClamAV returned null"); + + /* strip newline at the end (won't be present for zINSTREAM) + (also any trailing whitespace, which shouldn't exist, but we depend upon + this below, so double-check) */ + p = av_buffer + Ustrlen(av_buffer) - 1; + if (*p == '\n') *p = '\0'; + + DEBUG(D_acl) debug_printf_indent("Malware response: %s\n", av_buffer); + + while (isspace(*--p) && (p > av_buffer)) + *p = '\0'; + if (*p) ++p; + + /* colon in returned output? */ + if(!(p = Ustrchr(av_buffer,':'))) + return m_panic_defer(scanent, CUS callout_address, string_sprintf( + "ClamAV returned malformed result (missing colon): %s", + av_buffer)); + + /* strip filename */ + while (*p && isspace(*++p)) /**/; + vname = p; + + /* It would be bad to encounter a virus with "FOUND" in part of the name, + but we should at least be resistant to it. */ + p = Ustrrchr(vname, ' '); + result_tag = p ? p+1 : vname; + + if (Ustrcmp(result_tag, "FOUND") == 0) + { + /* p should still be the whitespace before the result_tag */ + while (isspace(*p)) --p; + *++p = '\0'; + /* Strip off the extended information too, which will be in parens + after the virus name, with no intervening whitespace. */ + if (*--p == ')') + { + /* "(hash:size)", so previous '(' will do; if not found, we have + a curious virus name, but not an error. */ + p = Ustrrchr(vname, '('); + if (p) + *p = '\0'; + } + malware_name = string_copy(vname); + DEBUG(D_acl) debug_printf_indent("Malware found, name \"%s\"\n", malware_name); + + } + else if (Ustrcmp(result_tag, "ERROR") == 0) + return m_panic_defer(scanent, CUS callout_address, + string_sprintf("ClamAV returned: %s", av_buffer)); + + else if (Ustrcmp(result_tag, "OK") == 0) + { + /* Everything should be OK */ + malware_name = NULL; + DEBUG(D_acl) debug_printf_indent("Malware not found\n"); + + } + else + return m_panic_defer(scanent, CUS callout_address, + string_sprintf("unparseable response from ClamAV: {%s}", av_buffer)); + + break; + } /* clamd */ +#endif + +#ifndef DISABLE_MAL_SOCK + case M_SOCK: /* "sock" scanner type ------------------------------------- */ + /* This code was derived by Martin Poole from the clamd code contributed + by David Saez and the cmdline code + */ + { + int bread; + uschar * commandline; + uschar av_buffer[1024]; + uschar * linebuffer; + uschar * sockline_scanner; + uschar sockline_scanner_default[] = "%s\n"; + const pcre *sockline_trig_re; + const pcre *sockline_name_re; + + /* find scanner command line */ + if ( (sockline_scanner = string_nextinlist(&av_scanner_work, &sep, + NULL, 0)) + && *sockline_scanner + ) + { /* check for no expansions apart from one %s */ + uschar * s = Ustrchr(sockline_scanner, '%'); + if (s++) + if ((*s != 's' && *s != '%') || Ustrchr(s+1, '%')) + return m_panic_defer_3(scanent, NULL, + US"unsafe sock scanner call spec", malware_daemon_ctx.sock); + } + else + sockline_scanner = sockline_scanner_default; + DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "cmdline: ", + string_printing(sockline_scanner)); + + /* find scanner output trigger */ + sockline_trig_re = m_pcre_nextinlist(&av_scanner_work, &sep, + "missing trigger specification", &errstr); + if (!sockline_trig_re) + return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock); + + /* find virus name regex */ + sockline_name_re = m_pcre_nextinlist(&av_scanner_work, &sep, + "missing virus name regex specification", &errstr); + if (!sockline_name_re) + return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock); + + /* prepare scanner call - security depends on expansions check above */ + commandline = string_sprintf( CS sockline_scanner, CS eml_filename); + DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "expanded: ", + string_printing(commandline)); + + /* Pass the command string to the socket */ + if (m_sock_send(malware_daemon_ctx.sock, commandline, Ustrlen(commandline), &errstr) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + /* Read the result */ + bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo); + + if (bread <= 0) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to read from socket (%s)", strerror(errno)), + malware_daemon_ctx.sock); + + if (bread == sizeof(av_buffer)) + return m_panic_defer_3(scanent, CUS callout_address, + US"buffer too small", malware_daemon_ctx.sock); + av_buffer[bread] = '\0'; + linebuffer = string_copy(av_buffer); + DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "answer: ", + string_printing(linebuffer)); + + /* try trigger match */ + if (regex_match_and_setup(sockline_trig_re, linebuffer, 0, -1)) + { + if (!(malware_name = m_pcre_exec(sockline_name_re, av_buffer))) + malware_name = US "unknown"; + DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "name: ", + string_printing(malware_name)); + } + else /* no virus found */ + malware_name = NULL; + break; + } +#endif + +#ifndef DISABLE_MAL_MKS + case M_MKSD: /* "mksd" scanner type ------------------------------------- */ + { + char *mksd_options_end; + int mksd_maxproc = 1; /* default, if no option supplied */ + int retval; + + if (scanner_options) + { + mksd_maxproc = (int)strtol(CS scanner_options, &mksd_options_end, 10); + if ( *scanner_options == '\0' + || *mksd_options_end != '\0' + || mksd_maxproc < 1 + || mksd_maxproc > 32 + ) + return m_panic_defer(scanent, CUS callout_address, + string_sprintf("invalid option '%s'", scanner_options)); + } + + if((malware_daemon_ctx.sock = ip_unixsocket(US "/var/run/mksd/socket", &errstr)) < 0) + return m_panic_defer(scanent, CUS callout_address, errstr); + + malware_name = NULL; + + DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan\n", scanner_name); + + if ((retval = mksd_scan_packed(scanent, malware_daemon_ctx.sock, eml_filename, tmo)) != OK) + { + close (malware_daemon_ctx.sock); + return retval; + } + break; + } +#endif + +#ifndef DISABLE_MAL_AVAST + case M_AVAST: /* "avast" scanner type ----------------------------------- */ + { + uschar buf[1024]; + uschar * scanrequest; + enum {AVA_HELO, AVA_OPT, AVA_RSP, AVA_DONE} avast_stage; + int nread; + uschar * error_message = NULL; + BOOL more_data = FALSE; + BOOL strict = TRUE; + + /* According to Martin Tuma @avast the protocol uses "escaped + whitespace", that is, every embedded whitespace is backslash + escaped, as well as backslash is protected by backslash. + The returned lines contain the name of the scanned file, a tab + and the [ ] marker. + [+] - not infected + [L] - infected + [E] - some error occurred + Such marker follows the first non-escaped TAB. For more information + see avast-protocol(5) + + We observed two cases: + -> SCAN /file + <- /file [E]0.0 Error 13 Permission denied + <- 451 SCAN Engine error 13 permission denied + + -> SCAN /file + <- /file… [E]3.0 Error 41120 The file is a decompression bomb + <- /file… [+]2.0 + <- /file… [+]2.0 0 Eicar Test Virus!!! + <- 200 SCAN OK + + If the scanner returns 4xx, DEFER is a good decision, combined + with a panic log entry, to get the admin's attention. + + If the scanner returns 200, we reject it as malware, if found any, + or, in case of an error, we set the malware message to the error + string. + + Some of the >= 42000 errors are message related - usually some + broken archives etc, but some of them are e.g. license related. + Once the license expires the engine starts returning errors for + every scanning attempt. I¹ have the full list of the error codes + but it is not a public API and is subject to change. It is hard + for me to say what you should do in case of an engine error. You + can have a “Treat * unscanned file as infection” policy or “Treat + unscanned file as clean” policy. ¹) Jakub Bednar + + */ + + if ( ( !ava_re_clean + && !(ava_re_clean = m_pcre_compile(ava_re_clean_str, &errstr))) + || ( !ava_re_virus + && !(ava_re_virus = m_pcre_compile(ava_re_virus_str, &errstr))) + || ( !ava_re_error + && !(ava_re_error = m_pcre_compile(ava_re_error_str, &errstr))) + ) + return malware_panic_defer(errstr); + + /* wait for result */ + for (avast_stage = AVA_HELO; + (nread = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) > 0; + ) + { + int slen = Ustrlen(buf); + if (slen >= 1) + { + + /* Multi line responses are bracketed between 210 … and nnn … */ + if (Ustrncmp(buf, "210", 3) == 0) + { + more_data = 1; + continue; + } + else if (more_data && isdigit(buf[0])) more_data = 0; + + switch (avast_stage) + { + case AVA_HELO: + if (more_data) continue; + if (Ustrncmp(buf, "220", 3) != 0) + goto endloop; /* require a 220 */ + goto sendreq; + + case AVA_OPT: + if (more_data) continue; + if (Ustrncmp(buf, "200", 3) != 0) + goto endloop; /* require a 200 */ + + sendreq: + { + int len; + /* Check for another option to send. Newline-terminate it. */ + if ((scanrequest = string_nextinlist(&av_scanner_work, &sep, + NULL, 0))) + { + if (Ustrcmp(scanrequest, "pass_unscanned") == 0) + { + DEBUG(D_acl) debug_printf_indent("pass unscanned files as clean\n"); + strict = FALSE; + goto sendreq; + } + scanrequest = string_sprintf("%s\n", scanrequest); + avast_stage = AVA_OPT; /* just sent option */ + DEBUG(D_acl) debug_printf_indent("send to avast OPTION: %s", scanrequest); + } + else + { + scanrequest = string_sprintf("SCAN %s\n", eml_dir); + avast_stage = AVA_RSP; /* just sent command */ + DEBUG(D_acl) debug_printf_indent("send to avast REQUEST: SCAN %s\n", eml_dir); + } + + /* send config-cmd or scan-request to socket */ + len = Ustrlen(scanrequest); + if (send(malware_daemon_ctx.sock, scanrequest, len, 0) == -1) + { + scanrequest[len-1] = '\0'; + return m_panic_defer_3(scanent, CUS callout_address, string_sprintf( + "unable to send request '%s' to socket (%s): %s", + scanrequest, scanner_options, strerror(errno)), malware_daemon_ctx.sock); + } + break; + } + + case AVA_RSP: + + if (isdigit(buf[0])) /* We're done */ + goto endloop; + + if (malware_name) /* Nothing else matters, just read on */ + break; + + if (pcre_exec(ava_re_clean, NULL, CS buf, slen, 0, 0, NULL, 0) == 0) + break; + + if ((malware_name = m_pcre_exec(ava_re_virus, buf))) + { + unescape(malware_name); + DEBUG(D_acl) + debug_printf_indent("unescaped malware name: '%s'\n", malware_name); + break; + } + + if (strict) /* treat scanner errors as malware */ + { + if ((malware_name = m_pcre_exec(ava_re_error, buf))) + { + unescape(malware_name); + DEBUG(D_acl) + debug_printf_indent("unescaped error message: '%s'\n", malware_name); + break; + } + } + else if (pcre_exec(ava_re_error, NULL, CS buf, slen, 0, 0, NULL, 0) == 0) + { + log_write(0, LOG_MAIN, "internal scanner error (ignored): %s", buf); + break; + } + + /* here also for any unexpected response from the scanner */ + DEBUG(D_acl) debug_printf("avast response not handled: '%s'\n", buf); + + goto endloop; + + default: log_write(0, LOG_PANIC, "%s:%d:%s: should not happen", + __FILE__, __LINE__, __FUNCTION__); + } + } + } + + endloop: + + if (nread == -1) error_message = US"EOF from scanner"; + else if (nread < 0) error_message = US"timeout from scanner"; + else if (nread == 0) error_message = US"got nothing from scanner"; + else if (buf[0] != '2') error_message = buf; + + DEBUG(D_acl) debug_printf_indent("sent to avast QUIT\n"); + if (send(malware_daemon_ctx.sock, "QUIT\n", 5, 0) == -1) + return m_panic_defer_3(scanent, CUS callout_address, + string_sprintf("unable to send quit request to socket (%s): %s", + scanner_options, strerror(errno)), malware_daemon_ctx.sock); + + if (error_message) + return m_panic_defer_3(scanent, CUS callout_address, error_message, malware_daemon_ctx.sock); + + } +#endif + } /* scanner type switch */ + + if (malware_daemon_ctx.sock >= 0) + (void) close (malware_daemon_ctx.sock); + malware_ok = TRUE; /* set "been here, done that" marker */ + } + +/* match virus name against pattern (caseless ------->----------v) */ +if (malware_name && regex_match_and_setup(re, malware_name, 0, -1)) + { + DEBUG(D_acl) debug_printf_indent( + "Matched regex to malware [%s] [%s]\n", malware_re, malware_name); + return OK; + } +else + return FAIL; +} + + +/************************************************* +* Scan an email for malware * +*************************************************/ + +/* This is the normal interface for scanning an email, which doesn't need a +filename; it's a wrapper around the malware_file function. + +Arguments: + malware_re match condition for "malware=" + timeout if nonzero, timeout in seconds + +Returns: Exim message processing code (OK, FAIL, DEFER, ...) + where true means malware was found (condition applies) +*/ +int +malware(const uschar * malware_re, int timeout) +{ +int ret = malware_internal(malware_re, NULL, timeout); + +if (ret == DEFER) av_failed = TRUE; +return ret; +} + + +/************************************************* +* Scan a file for malware * +*************************************************/ + +/* This is a test wrapper for scanning an email, which is not used in +normal processing. Scan any file, using the Exim scanning interface. +This function tampers with various global variables so is unsafe to use +in any other context. + +Arguments: + eml_filename a file holding the message to be scanned + +Returns: Exim message processing code (OK, FAIL, DEFER, ...) + where true means malware was found (condition applies) +*/ +int +malware_in_file(uschar *eml_filename) +{ +uschar message_id_buf[64]; +int ret; + +/* spool_mbox() assumes various parameters exist, when creating +the relevant directory and the email within */ + +(void) string_format(message_id_buf, sizeof(message_id_buf), + "dummy-%d", vaguely_random_number(INT_MAX)); +message_id = message_id_buf; +sender_address = US"malware-sender@example.net"; +return_path = US""; +recipients_list = NULL; +receive_add_recipient(US"malware-victim@example.net", -1); +f.enable_dollar_recipients = TRUE; + +ret = malware_internal(US"*", eml_filename, 0); + +Ustrncpy(spooled_message_id, message_id, sizeof(spooled_message_id)); +spool_mbox_ok = 1; + +/* don't set no_mbox_unspool; at present, there's no way for it to become +set, but if that changes, then it should apply to these tests too */ + +unspool_mbox(); + +/* silence static analysis tools */ +message_id = NULL; + +return ret; +} + + +void +malware_init(void) +{ +if (!malware_default_re) + malware_default_re = regex_must_compile(malware_regex_default, FALSE, TRUE); + +#ifndef DISABLE_MAL_DRWEB +if (!drweb_re) + drweb_re = regex_must_compile(drweb_re_str, FALSE, TRUE); +#endif +#ifndef DISABLE_MAL_FSECURE +if (!fsec_re) + fsec_re = regex_must_compile(fsec_re_str, FALSE, TRUE); +#endif +#ifndef DISABLE_MAL_KAV +if (!kav_re_sus) + kav_re_sus = regex_must_compile(kav_re_sus_str, FALSE, TRUE); +if (!kav_re_inf) + kav_re_inf = regex_must_compile(kav_re_inf_str, FALSE, TRUE); +#endif +#ifndef DISABLE_MAL_AVAST +if (!ava_re_clean) + ava_re_clean = regex_must_compile(ava_re_clean_str, FALSE, TRUE); +if (!ava_re_virus) + ava_re_virus = regex_must_compile(ava_re_virus_str, FALSE, TRUE); +if (!ava_re_error) + ava_re_error = regex_must_compile(ava_re_error_str, FALSE, TRUE); +#endif +#ifndef DISABLE_MAL_FFROT6D +if (!fprot6d_re_error) + fprot6d_re_error = regex_must_compile(fprot6d_re_error_str, FALSE, TRUE); +if (!fprot6d_re_virus) + fprot6d_re_virus = regex_must_compile(fprot6d_re_virus_str, FALSE, TRUE); +#endif +} + + +gstring * +malware_show_supported(gstring * g) +{ +g = string_cat(g, US"Malware:"); +for (struct scan * sc = m_scans; sc->scancode != (scanner_t)-1; sc++) + g = string_fmt_append(g, " %s", sc->name); +return string_cat(g, US"\n"); +} + + +# endif /*!MACRO_PREDEF*/ +#endif /*WITH_CONTENT_SCAN*/ +/* + * vi: aw ai sw=2 + */ |