sms: Introduce VTY-configurable minimum SMS validity period

This is meant as a safeguard against users or user equipment which
doesn't set a reasonable validity period.  Using this setting, the
SMSC administrator can set a minimum SMS validity period. Any SMS
submitted with lower validity period will be extended to that minimum.

Change-Id: I192528a6f9059d158fa12876a247d61bd7edaec8
Related: OS#5567
diff --git a/src/libmsc/gsm_04_11.c b/src/libmsc/gsm_04_11.c
index 722973e..743e272 100644
--- a/src/libmsc/gsm_04_11.c
+++ b/src/libmsc/gsm_04_11.c
@@ -626,6 +626,12 @@
 		  osmo_hexdump(gsms->user_data, gsms->user_data_len));
 
 	gsms->validity_minutes = gsm340_validity_period(sms_vpf, sms_vp);
+	if (gsms->validity_minutes < net->sms_queue_cfg->minimum_validity_mins) {
+		LOG_TRANS(trans, LOGL_INFO, "Overriding user-provided validity period (%lu) "
+			  "with minimum SMSC validity period (%u) minutes\n", gsms->validity_minutes,
+			  net->sms_queue_cfg->minimum_validity_mins);
+		gsms->validity_minutes = net->sms_queue_cfg->minimum_validity_mins;
+	}
 
 	rc = sms_route_mt_sms(trans, gsms);
 
diff --git a/src/libmsc/smpp_openbsc.c b/src/libmsc/smpp_openbsc.c
index 64d4f1e..91666a9 100644
--- a/src/libmsc/smpp_openbsc.c
+++ b/src/libmsc/smpp_openbsc.c
@@ -267,6 +267,13 @@
 	else
 		sms->validity_minutes = (t_validity_absolute - t_now) / 60;
 
+	if (sms->validity_minutes < net->sms_queue_cfg->minimum_validity_mins) {
+		LOGP(DLSMS, LOGL_INFO, "SMS to %s: Overriding ESME-provided validity period (%lu) "
+		     "with minimum SMSC validity period (%u) minutes\n", submit->destination_addr,
+		     sms->validity_minutes, net->sms_queue_cfg->minimum_validity_mins);
+		sms->validity_minutes = net->sms_queue_cfg->minimum_validity_mins;
+	}
+
 	*psms = sms;
 	return ESME_ROK;
 }
diff --git a/src/libmsc/sms_queue.c b/src/libmsc/sms_queue.c
index 24811c5..9f18f4f 100644
--- a/src/libmsc/sms_queue.c
+++ b/src/libmsc/sms_queue.c
@@ -475,6 +475,7 @@
 	sqcfg->delete_delivered = true;
 	sqcfg->delete_expired = true;
 	sqcfg->default_validity_mins = 7 * 24 * 60; /* 7 days */
+	sqcfg->minimum_validity_mins = 1;
 	sqcfg->db_file_path = talloc_strdup(ctx, SMS_DEFAULT_DB_FILE_PATH);
 
 	return sqcfg;
diff --git a/src/libmsc/smsc_vty.c b/src/libmsc/smsc_vty.c
index 547b7d5..e99b236 100644
--- a/src/libmsc/smsc_vty.c
+++ b/src/libmsc/smsc_vty.c
@@ -99,12 +99,16 @@
 }
 
 DEFUN(cfg_sms_def_val_per, cfg_sms_def_val_per_cmd,
-      "validity-period default <1-5256000>",
+      "validity-period (minimum|default) <1-5256000>",
       "Configure validity period for SMS\n"
+      "Minimum SMS validity period in minutes\n"
       "Default SMS validity period in minutes\n"
-      "Default SMS validity period in minutes\n")
+      "Validity period in minutes\n")
 {
-	smqcfg->default_validity_mins = atoi(argv[0]);
+	if (!strcmp(argv[0], "minimum"))
+		smqcfg->minimum_validity_mins = atoi(argv[1]);
+	else
+		smqcfg->default_validity_mins = atoi(argv[1]);
 	return CMD_SUCCESS;
 }
 
@@ -177,6 +181,7 @@
 	vty_out(vty, " database delete-delivered %u%s", smqcfg->delete_delivered, VTY_NEWLINE);
 	vty_out(vty, " database delete-expired %u%s", smqcfg->delete_expired, VTY_NEWLINE);
 
+	vty_out(vty, " validity-period minimum %u%s", smqcfg->minimum_validity_mins, VTY_NEWLINE);
 	vty_out(vty, " validity-period default %u%s", smqcfg->default_validity_mins, VTY_NEWLINE);
 
 	return 0;