Update to protocol used by avast 2.2.0 (Multiline responses) (Bug 2112)

Based on a patch by Victor Ustugov.

1 files changed, 34 insertions, 21 deletions

diff --git a/src/src/malware.c b/src/src/malware.c
index 5b9d5ad58..948aedea1 100644
--- a/src/src/malware.c
+++ b/src/src/malware.c
@@ -1893,6 +1893,7 @@ b_seek:   err = errno;
       uschar * scanrequest;
       enum {AVA_HELO, AVA_OPT, AVA_RSP, AVA_DONE} avast_stage;
       int nread;
+      int more_data;
 
       /* According to Martin Tuma @avast the protocol uses "escaped
       whitespace", that is, every embedded whitespace is backslash
@@ -1902,7 +1903,9 @@ b_seek:   err = errno;
       [+] - not infected
       [L] - infected
       [E] - some error occured
-      Such marker follows the first non-escaped TAB.  */
+      Such marker follows the first non-escaped TAB.  For more information
+      see avast-protocol(5)
+      */
       if (  (  !ava_re_clean
             && !(ava_re_clean = m_pcre_compile(ava_re_clean_str, &errstr)))
 	 || (  !ava_re_virus
@@ -1918,17 +1921,25 @@ b_seek:   err = errno;
 	int slen = Ustrlen(buf);
 	if (slen >= 1)
 	  {
-	  DEBUG(D_acl) debug_printf_indent("got from avast: %s\n", buf);
+
+          /* 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 (Ustrncmp(buf, "210", 3) == 0)
-		break;				/* ignore 210 responses */
+              if (more_data) continue;
 	      if (Ustrncmp(buf, "200", 3) != 0)
 		goto endloop;			/* require a 200 */
 
@@ -1941,11 +1952,13 @@ b_seek:   err = errno;
 		{
 		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 */
@@ -1961,15 +1974,27 @@ b_seek:   err = errno;
 	      }
 
 	    case AVA_RSP:
-	      if (Ustrncmp(buf, "210", 3) == 0)
-		break;  /* ignore the "210 SCAN DATA" message */
+
+	      if (Ustrncmp(buf, "200", 3) == 0)
+		{ /* we're done finally */
+		if (send(sock, "QUIT\n", 5, 0) < 0) /* courtesy */
+		  return m_errlog_defer_3(scanent, CUS callout_address,
+			  string_sprintf(
+			      "unable to send quit request to socket (%s): %s",
+			      scanner_options, strerror(errno)),
+			      sock);
+
+		avast_stage = AVA_DONE;
+                goto endloop;
+		}
+
+              if (malware_name) break;  /* found malware already, nothing to do anymore */
 
 	      if (pcre_exec(ava_re_clean, NULL, CS buf, slen,
 		    0, 0, ovector, nelem(ovector)) > 0)
 		break;
 
-	      if (  !malware_name
-	         && (malware_name = m_pcre_exec(ava_re_virus, buf)))
+	      if (malware_name = m_pcre_exec(ava_re_virus, buf))
 		{ /* remove backslash in front of [whitespace|backslash] */
 		uschar * p, * p0;
 		for (p = malware_name; *p; ++p)
@@ -1977,22 +2002,10 @@ b_seek:   err = errno;
 		    for (p0 = p; *p0; ++p0) *p0 = p0[1];
 
 		DEBUG(D_acl)
-		  debug_printf_indent("unescaped m-name: '%s'\n", malware_name);
+		  debug_printf_indent("unescaped malware name: '%s'\n", malware_name);
 		break;
 		}
 
-	      if (Ustrncmp(buf, "200 SCAN OK", 11) == 0)
-		{ /* we're done finally */
-		if (send(sock, "QUIT\n", 5, 0) < 0) /* courtesy */
-		  return m_errlog_defer_3(scanent, CUS callout_address,
-			  string_sprintf(
-			      "unable to send quit request to socket (%s): %s",
-			      scanner_options, strerror(errno)),
-			      sock);
-
-		avast_stage = AVA_DONE;
-		}
-
 	      /* here also for any unexpected response from the scanner */
 	      goto endloop;