Added security header feature

Signed-off-by: Janos SUTO <sj@acts.hu>

RELEASE_NOTES

@@ -1,3 +1,9 @@
+1.3.10:
+-------
+
+- Added security header feature
+
+
 1.3.9:
 ------
 

VERSION

@@ -1 +1 @@
-1.3.9
+1.3.10

etc/example.conf

@@ -221,3 +221,11 @@ tweak_sent_time_offset=0
 ; whether to enable (1) or not (0) the extra mmap dedup test feature
 ; if you change it, be sure to stop, then start piler
 mmap_dedup_test=0
+
+; security header that must be present in the first mail header of
+; the message. If the security_header value is not empty, then the
+; parser checks for this header line. Unless it's found it will discard
+; the given email. Note that this feature is supposed to be a security
+; mechanism against unwanted email in the archive if limiting smtp
+; clients via an IP-address list is not feasible.
+security_header=

src/cfg.c

@@ -84,6 +84,7 @@ struct _parse_rule config_parse_rules[] =
    { "piler_header_field", "string", (void*) string_parser, offsetof(struct config, piler_header_field), "X-piler-id:", MAXVAL-1},
    { "process_rcpt_to_addresses", "integer", (void*) int_parser, offsetof(struct config, process_rcpt_to_addresses), "0", sizeof(int)},
    { "queuedir", "string", (void*) string_parser, offsetof(struct config, queuedir), QUEUE_DIR, MAXVAL-1},
+   { "security_header", "string", (void*) string_parser, offsetof(struct config, security_header), "", MAXVAL-1},
    { "server_id", "integer", (void*) int_parser, offsetof(struct config, server_id), "0", sizeof(int)},
    { "smtp_timeout", "integer", (void*) int_parser, offsetof(struct config, smtp_timeout), "60", sizeof(int)},
    { "spam_header_line", "string", (void*) string_parser, offsetof(struct config, spam_header_line), "", MAXVAL-1},

src/cfg.h

@@ -64,6 +64,8 @@ struct config {
 
    int default_retention_days;
 
+   char security_header[MAXVAL];
+
    // mysql stuff
 
    char mysqlcharset[MAXVAL];

src/defs.h

@@ -209,6 +209,8 @@ struct parser_state {
    unsigned int bodylen;
    unsigned int tolen;
    unsigned int todomainlen;
+   unsigned int found_security_header;
+
    int journaltolen;
 
    int retention;

src/parser.c

@@ -199,6 +199,10 @@ int parse_line(char *buf, struct parser_state *state, struct session_data *sdata
          sdata->restored_copy = 1;
       }
 
+      if(cfg->security_header && state->found_security_header == 0 && strstr(buf, cfg->security_header)){
+         state->found_security_header = 1;
+      }
+
       if(*(cfg->piler_header_field) != 0 && strncmp(buf, cfg->piler_header_field, strlen(cfg->piler_header_field)) == 0){
          sdata->restored_copy = 1;
       }

src/parser_utils.c

@@ -102,6 +102,8 @@ void init_state(struct parser_state *state){
    state->journaltolen = 0;
 
    state->retention = 0;
+
+   state->found_security_header = 0;
 }
 
 

src/piler.c

@@ -101,11 +101,43 @@ void child_sighup_handler(int sig){
 }
 
 
+int perform_checks(char *filename, struct session_data *sdata, struct data *data, struct parser_state *parser_state, struct config *cfg){
+
+   if(cfg->security_header && parser_state->found_security_header == 0){
+      syslog(LOG_PRIORITY, "%s: discarding: missing security header", filename);
+      return ERR_DISCARDED;
+   }
+
+   char *arule = check_against_ruleset(data->archiving_rules, parser_state, sdata->tot_len, sdata->spam_message);
+
+   if(arule){
+      syslog(LOG_PRIORITY, "%s: discarding: archiving policy: *%s*", filename, arule);
+      return ERR_DISCARDED;
+   }
+
+
+   if(cfg->archive_only_mydomains == 1 && sdata->internal_sender == 0 && sdata->internal_recipient == 0){
+      syslog(LOG_PRIORITY, "%s: discarding: not on mydomains", filename);
+      return ERR_DISCARDED;
+   }
+
+   make_digests(sdata, cfg);
+
+   if(sdata->hdr_len < 10){
+      syslog(LOG_PRIORITY, "%s: invalid message, hdr_len: %d", filename, sdata->hdr_len);
+      return ERR;
+   }
+
+   int rc = process_message(sdata, parser_state, data, cfg);
+   unlink(parser_state->message_id_hash);
+
+   return rc;
+}
+
+
 int process_email(char *filename, struct session_data *sdata, struct data *data, int size, struct config *cfg){
-   int rc;
    char tmpbuf[SMALLBUFSIZE];
    char *status=S_STATUS_UNDEF;
-   char *arule;
    char *p;
    struct timezone tz;
    struct timeval tv1, tv2;
@@ -144,29 +176,7 @@ int process_email(char *filename, struct session_data *sdata, struct data *data,
       } while(rcpt);
    }
 
-   arule = check_against_ruleset(data->archiving_rules, &parser_state, sdata->tot_len, sdata->spam_message);
-
-   if(arule){
-      syslog(LOG_PRIORITY, "%s: discarding: archiving policy: *%s*", filename, arule);
-      rc = ERR_DISCARDED;
-   }
-   else if(cfg->archive_only_mydomains == 1 && sdata->internal_sender == 0 && sdata->internal_recipient == 0){
-      syslog(LOG_PRIORITY, "%s: discarding: not on mydomains", filename);
-      rc = ERR_DISCARDED;
-   }
-   else {
-      make_digests(sdata, cfg);
-
-      if(sdata->hdr_len < 10){
-         syslog(LOG_PRIORITY, "%s: invalid message, hdr_len: %d", filename, sdata->hdr_len);
-         rc = ERR;
-      }
-      else {
-         rc = process_message(sdata, &parser_state, data, cfg);
-         unlink(parser_state.message_id_hash);
-      }
-   }
-
+   int rc = perform_checks(filename, sdata, data, &parser_state, cfg);
    unlink(sdata->tmpframe);
 
    remove_stripped_attachments(&parser_state);