Detecting if MX is defined for an email address

diff --git a/data-feed/feed01.tst b/data-feed/feed01.tst
index 38e7cc582aa9e26ef0006521f0475bb5f5dba4c1..acbacc46f5290de685082382e752567ae67844db 100644 (file)
--- a/data-feed/feed01.tst
+++ b/data-feed/feed01.tst
@@ -1,6 +1,6 @@
 #very simple  test to feed SMTP server
 #====================================================
-T:Very Simple email sending
+T:Testing if MX is found
 R:220 mailleur.example.com ESMTP (cleartext) emlrcvr...
 #====================================================
 S:HELO example.com
@@ -9,9 +9,9 @@ R:250-mailleur.example.com, link (cleartext) ready,...
 S:MAIL FROM: <postmaster@example.com>
 R:250 2.1.3 postmaster@example.com.. sender ok
 S:RCPT TO: <dom1user1@subdom0.example.com>
-S:563 0.0.0 No valid MX found for recipient domain name (subdom0.example.com)
+R:563 5.6.3 No valid MX found for recipient domain name (rcpt=subdom0.example.com)
 S:RCPT TO: <dom1user1@subdom1.example.com>
-R:250 3.5.3 Message accepted for delivery
+R:250 2.6.4 Address accepted
 S:QUIT
 R:221 2.0.0 Bye, closing connection...
 #-------------------------------------------------------------------------

diff --git a/data-feed/xxfeed.tst b/data-feed/xxfeed.tst
index 7d7a87cd4980d0555b01624b2daf0ea8e1df76c1..acbacc46f5290de685082382e752567ae67844db 100644 (file)
--- a/data-feed/xxfeed.tst
+++ b/data-feed/xxfeed.tst
@@ -9,7 +9,7 @@ R:250-mailleur.example.com, link (cleartext) ready,...
 S:MAIL FROM: <postmaster@example.com>
 R:250 2.1.3 postmaster@example.com.. sender ok
 S:RCPT TO: <dom1user1@subdom0.example.com>
-R:563 0.0.0 No valid MX found for recipient domain name (subdom0.example.com)
+R:563 5.6.3 No valid MX found for recipient domain name (rcpt=subdom0.example.com)
 S:RCPT TO: <dom1user1@subdom1.example.com>
 R:250 2.6.4 Address accepted
 S:QUIT

diff --git a/lib/Makefile b/lib/Makefile
index 1fe3def1bd14c877dd571ef22495e377fa0c068e..dd27e330991b7e8d2bfdf5df54de85381c277775 100644 (file)
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -39,7 +39,7 @@ modrec.o:                                     \
 
 lvleml.o:                                      \
           subrou.h                             \
-          unieml.h                             \
+          unieml.h unidns.h                    \
           lvleml.h lvleml.c
 
 gesspf.o:                                      \

diff --git a/lib/lvleml.c b/lib/lvleml.c
index 7fab83ec28f0deb29f19141ff78df830809c434b..b00030145f6876d7677ce038452582efef9e8231 100644 (file)
--- a/lib/lvleml.c
+++ b/lib/lvleml.c
@@ -18,6 +18,7 @@
 #include        <unistd.h>
 
 #include       "subrou.h"
+#include       "unidns.h"
 #include       "unieml.h"
 #include       "devlog.h"
 #include       "lvleml.h"
@@ -461,12 +462,14 @@ static _Bool checkto(CONTYP *contact,char *rcptto)
 #define OPEP     "lvleml.c:checkto,"
 _Bool success;
 const char *detail;
+const char *domain;
 char *report;
 _Bool proceed;
 int phase;
 
 success=false;
 detail="Address accepted";
+domain=(const char *)0;
 report=(char *)0;
 proceed=true;
 phase=0;
@@ -489,19 +492,33 @@ while (proceed==true) {
       rcptto[strlen(rcptto)-1]='\000'; 
       (void) memmove(rcptto,rcptto+1,strlen(rcptto));
       break;
-    case 2      :       //checking repto format
-      if (eml_isemailok(rcptto,&report)==false) {
+    case 2      :       //checking rcptto format
+      if (eml_isemailok(rcptto,&domain,&report)==false) {
         (void) transmit(contact,"%d 5.6.2 %s",NOTEML,report);
         report=rou_freestr(report);
         phase=999;      //no need to go further
         }
       break;
-    case 3      :       //Storing rcpt to
+    case 3      :       //Do we have a domain MX
+      if (domain!=(const char *)0) {  //always
+        MXTYP **mx;
+
+        if ((mx=dns_getmx(domain))==(MXTYP **)0) {
+          (void) transmit(contact,"%d 5.6.3 %s (rcpt=%s)",
+                                  MISSMX,
+                                  "No valid MX found for recipient domain name",
+                                  domain);
+          phase=999;      //no need to go further
+          }
+        mx=dns_freemxlist(mx);
+        }
+      break;
+    case 4      :       //Storing rcpt to
       if (eml_addemail(&(contact->rcptto),rcptto)==false) {
         detail="duplicate recipients will be consolidated";
         }
       break;
-    case 4      :       //everything ok
+    case 5      :       //everything ok
       (void) transmit(contact,"%d 2.6.4 %s",CMDOK,detail);
       success=true;
       break;

diff --git a/lib/unidns.c b/lib/unidns.c
index 20b416af5af026871ce673e4adf7dbd37c1b03c1..f418859963770819d9bf1e43934cd3cc6af74714 100644 (file)
--- a/lib/unidns.c
+++ b/lib/unidns.c
@@ -95,7 +95,7 @@ return got;
 /*     from DNS record.                                */
 /*                                                      */
 /********************************************************/
-static char **extracting(RSPTYP *rsp,int rsplen,char *request,char *field)
+static char **extracting(RSPTYP *rsp,int rsplen,const char *request,char *field)
 
 {
 #define        OPEP    "unidns.c:extracting,"
@@ -316,7 +316,7 @@ return mxlist;
 /*     MX preference (low preference first)            */
 /*                                                      */
 /********************************************************/
-PUBLIC MXTYP **dns_getmx(char *domain)
+PUBLIC MXTYP **dns_getmx(const char *domain)
 
 {
 #define OPEP    "unidns.c:dns_getmx"
@@ -338,23 +338,38 @@ while (proceed==true) {
   switch (phase) {
     case 0      :       //Are the parameters available
       if ((domain==(char *)0)||(strlen(domain)==0)) {
-        (void) rou_alert(0,"%s missing domainame",OPEP);
+        (void) rou_alert(0,"%s missing domainname",OPEP);
         phase=999;      //trouble trouble
         }
       break;
-    case 1      :       //Requesting MX for domain
+    case 1      :       //cleaning domain
+      if (domain!=(char *)0) {  //always
+        char *ptr;
+
+        if ((ptr=strchr(domain,'@'))!=(char *)0) {
+          ptr++;
+          if (strlen(ptr)==0) {
+            (void) rou_alert(0,"%s Incorrect domainname <%s>",OPEP,domain);
+            phase=999;      //trouble trouble
+            }
+          domain=ptr;
+          }
+        }
+      break;
+    case 2      :       //Requesting MX for domain
+      (void) rou_alert(0,"%s JMPDBG domain=<%s>",OPEP,domain);
       answer=myquery(domain,C_IN,T_MX,rsp.buf,sizeof(rsp.buf));
       if (answer<=0) 
         phase=999;      //Trouble trouble to get MX
       break;
-    case 2      :       //extracting result
+    case 3      :       //extracting result
       if (answer>=sizeof(rsp.buf))
         answer=sizeof(rsp.buf)-1;
       list=extracting(&rsp,answer,domain,"MX");
       if (list==(char **)0)
         phase=999;      //list empty?
       break;
-    case 3      :       //ordering list
+    case 4      :       //ordering list
       answer=0;
       for (int i=0;list[i]!=(char *)0;i+=2) {
        if ((list[i+1]!=(char *)0)&&(strlen(list[i+1])>0)) {

diff --git a/lib/unidns.h b/lib/unidns.h
index 689d706d9335da59acfd92f1e82d0143357ce6a9..7b8ee83e672dd9c2d482d9f2b7e25561c436285e 100644 (file)
--- a/lib/unidns.h
+++ b/lib/unidns.h
@@ -24,7 +24,7 @@ extern MXTYP **dns_freemxlist(MXTYP **mxlist);
 
 //procedure to get a list of MX IP releated to a specific
 //domain.
-extern MXTYP **dns_getmx(char *domain);
+extern MXTYP **dns_getmx(const char *domain);
 
 //Procedure to check if an IP (Origin IP) is part
 //of domain A record list

diff --git a/lib/unieml.c b/lib/unieml.c
index d2d9afe07464d4549c423bdb38c9064a7421a1e5..8aeab4e03fc1e465f6350b07a2ebf8da83ab8b88 100644 (file)
--- a/lib/unieml.c
+++ b/lib/unieml.c
@@ -443,47 +443,54 @@ return status;
 /*      acceptable.                                     */
 /*                                                      */
 /********************************************************/
-PUBLIC _Bool eml_isemailok(char *email,char **rapport)
+PUBLIC _Bool eml_isemailok(char *email,const char **domain,char **rapport)
 
 {
 #define OPEP    "unieml.c:eml_isemailok"
 
 int status;
 char *localpart;
-char *domain;
 int phase;
 _Bool proceed;
 
 status=false;
 localpart=(char *)0;
-domain=(char *)0;
+*domain=(const char *)0;
 phase=0;
 proceed=true;
 while (proceed==true) {
   //(void) rou_alert(0,"JMPDBG %s phase='%d'",OPEP,phase);
   switch (phase) {
     case 0      :       //do we have an email
-      if (email==(char *)0) {
+      if ((email==(char *)0)||strlen(email)==0) {
         (void) rou_alert(0,"%s Email missing! (bug?)",OPEP);
         proceed=false;
         }
       break;
-    case 1      :       //duplicating email to localpart
+    case 1      :       //splitting local domain part
+      if ((*domain=strchr(email,'@'))!=(const char *)0) 
+        (*domain)++;
+      if ((*domain)==(char *)0) {
+        *rapport=strdup("Missing domain part");
+        phase=999;      //trouble trouble
+        }
+      break;
+    case 2      :       //double checking domain part
+      if (strchr(*domain,'@')!=(char *)0) {
+        *rapport=strdup("malformed domain part");
+        *domain=(const char *)0;
+        phase=999;      //trouble trouble
+        }
+      break;
+    case 3      :       //duplicating email to localpart
       localpart=strdup(email);
+      *(strchr(localpart,'@'))='\000';  //removing domain
       if (strlen(localpart)==0) {
         *rapport=strdup("email address is empty");
-        phase=999;      //never reached
+        phase=999;      //trouble trouble
         }
       break;
-    case 2      :       //splitting local domain part
-      if ((domain=strchr(localpart,'@'))!=(char *)0) 
-        domain++;
-      if (domain==(char *)0) {
-        *rapport=strdup("Missing domain part");
-        phase=999;      //never reached
-        }
-      break;
-    case 3      :       //checking localpart email
+    case 4      :       //checking localpart email
       if (strlen(localpart)>0) {        //always
         char *ptr;
         char cmt[200];
@@ -509,12 +516,6 @@ while (proceed==true) {
           } 
         }
       break;
-    case 4      :       //checking domain part 
-      if (strlen(domain)==0) {
-        *rapport=strdup("No domain part");
-        phase=999;      //No need to go further
-        }
-      break;
     case 5      :       //everythin fine
       status=true;
       break;

diff --git a/lib/unieml.h b/lib/unieml.h
index 962573a0a0d3df03c2827800a36dd454a8d73d29..a680f3758d0dc156df53a9390c2c8679ae13818c 100644 (file)
--- a/lib/unieml.h
+++ b/lib/unieml.h
@@ -20,6 +20,7 @@
 #define CMDBAD  502             //command not implemented
 #define DATRJC  521             //Data Rejected
 #define NOTEML  553             //Not an email address
+#define MISSMX  563             //NO MX found for recipient
 
 
 //list of keyword
@@ -73,6 +74,6 @@ extern _Bool eml_addemail(char ***emails,char *email);
 
 //procedure to check email address format
 //of an email address
-extern _Bool eml_isemailok(char *email,char **report);
+extern _Bool eml_isemailok(char *email,const char **domain,char **report);
 
 #endif