Use libvlr in libmsc (large refactoring)

Original libvlr code is by Harald Welte <laforge@gnumonks.org>,
polished and tweaked by Neels Hofmeyr <nhofmeyr@sysmocom.de>.

This is a long series of trial-and-error development collapsed in one patch.
This may be split in smaller commits if reviewers prefer that. If we can keep
it as one, we have saved ourselves the additional separation work.

SMS:

The SQL based lookup of SMS for attached subscribers no longer works since the
SQL database no longer has the subscriber data. Replace with a round-robin on
the SMS recipient MSISDNs paired with a VLR subscriber RAM lookup whether the
subscriber is currently attached.

If there are many SMS for not-attached subscribers in the SMS database, this
will become inefficient: a DB hit returns a pending SMS, the RAM lookup will
reveal that the subscriber is not attached, after which the DB is hit for the
next SMS. It would become more efficient e.g. by having an MSISDN based hash
list for the VLR subscribers and by marking non-attached SMS recipients in the
SMS database so that they can be excluded with the SQL query already.

There is a sanity limit to do at most 100 db hits per attempt to find a pending
SMS. So if there are more than 100 stored SMS waiting for their recipients to
actually attach to the MSC, it may take more than one SMS queue trigger to
deliver SMS for subscribers that are actually attached.

This is not very beautiful, but is merely intended to carry us over to a time
when we have a proper separate SMSC entity.

Introduce gsm_subscriber_connection ref-counting in libmsc.

Remove/Disable VTY and CTRL commands to create subscribers, which is now a task
of the OsmoHLR. Adjust the python tests accordingly.

Remove VTY cmd subscriber-keep-in-ram.

Use OSMO_GSUP_PORT = 4222 instead of 2222. See
I4222e21686c823985be8ff1f16b1182be8ad6175.

So far use the LAC from conn->bts, will be replaced by conn->lac in
Id3705236350d5f69e447046b0a764bbabc3d493c.

Related: OS#1592 OS#1974
Change-Id: I639544a6cdda77a3aafc4e3446a55393f60e4050
diff --git a/src/libcommon/debug.c b/src/libcommon/debug.c
index 088902a..dc79a84 100644
--- a/src/libcommon/debug.c
+++ b/src/libcommon/debug.c
@@ -32,7 +32,6 @@
 #include <osmocom/core/logging.h>
 #include <osmocom/gprs/gprs_msgb.h>
 #include <openbsc/gsm_data.h>
-#include <openbsc/gsm_subscriber.h>
 #include <openbsc/debug.h>
 
 /* default categories */
@@ -189,13 +188,13 @@
 
 static int filter_fn(const struct log_context *ctx, struct log_target *tar)
 {
-	const struct gsm_subscriber *subscr = ctx->ctx[LOG_CTX_VLR_SUBSCR];
+	const struct vlr_subscr *vsub = ctx->ctx[LOG_CTX_VLR_SUBSCR];
 	const struct bsc_subscr *bsub = ctx->ctx[LOG_CTX_BSC_SUBSCR];
 	const struct gprs_nsvc *nsvc = ctx->ctx[LOG_CTX_GB_NSVC];
 	const struct gprs_nsvc *bvc = ctx->ctx[LOG_CTX_GB_BVC];
 
 	if ((tar->filter_map & (1 << LOG_FLT_VLR_SUBSCR)) != 0
-	    && subscr && subscr == tar->filter_data[LOG_FLT_VLR_SUBSCR])
+	    && vsub && vsub == tar->filter_data[LOG_FLT_VLR_SUBSCR])
 		return 1;
 
 	if ((tar->filter_map & (1 << LOG_FLT_BSC_SUBSCR)) != 0
@@ -220,21 +219,3 @@
 	.cat = default_categories,
 	.num_cat = ARRAY_SIZE(default_categories),
 };
-
-void log_set_filter_vlr_subscr(struct log_target *target,
-			       struct gsm_subscriber *vlr_subscr)
-{
-	struct gsm_subscriber **fsub = (void*)&target->filter_data[LOG_FLT_VLR_SUBSCR];
-
-	/* free the old data */
-	if (*fsub) {
-		subscr_put(*fsub);
-		*fsub = NULL;
-	}
-
-	if (vlr_subscr) {
-		target->filter_map |= (1 << LOG_FLT_VLR_SUBSCR);
-		*fsub = subscr_get(vlr_subscr);
-	} else
-		target->filter_map &= ~(1 << LOG_FLT_VLR_SUBSCR);
-}
diff --git a/src/libcommon/gsm_data.c b/src/libcommon/gsm_data.c
index db7de08..7c717a4 100644
--- a/src/libcommon/gsm_data.c
+++ b/src/libcommon/gsm_data.c
@@ -471,3 +471,13 @@
 		cell_options->radio_link_timeout = (value >> 2) - 1;
 	}
 }
+
+bool classmark_is_r99(struct gsm_classmark *cm)
+{
+	int rev_lev = 0;
+	if (cm->classmark1_set)
+		rev_lev = cm->classmark1.rev_lev;
+	else if (cm->classmark2_len > 0)
+		rev_lev = (cm->classmark2[0] >> 5) & 0x3;
+	return rev_lev >= 2;
+}
diff --git a/src/libcommon/gsm_subscriber_base.c b/src/libcommon/gsm_subscriber_base.c
index 1ecdee5..018ed21 100644
--- a/src/libcommon/gsm_subscriber_base.c
+++ b/src/libcommon/gsm_subscriber_base.c
@@ -31,133 +31,34 @@
 #include <osmocom/core/utils.h>
 #include <openbsc/gsm_subscriber.h>
 #include <openbsc/debug.h>
+#include <openbsc/vlr.h>
 
 LLIST_HEAD(active_subscribers);
 void *tall_subscr_ctx;
 
-/* for the gsm_subscriber.c */
-struct llist_head *subscr_bsc_active_subscribers(void)
+/* return static buffer with printable name of VLR subscriber */
+const char *vlr_subscr_name(struct vlr_subscr *vsub)
 {
-	return &active_subscribers;
-}
-
-
-char *subscr_name(struct gsm_subscriber *subscr)
-{
-	if (!subscr)
+	static char buf[32];
+	if (!vsub)
 		return "unknown";
-
-	if (strlen(subscr->name))
-		return subscr->name;
-
-	return subscr->imsi;
+	if (vsub->msisdn[0])
+		snprintf(buf, sizeof(buf), "MSISDN:%s", vsub->msisdn);
+	else if (vsub->imsi[0])
+		snprintf(buf, sizeof(buf), "IMSI:%s", vsub->imsi);
+	else if (vsub->tmsi != GSM_RESERVED_TMSI)
+		snprintf(buf, sizeof(buf), "TMSI:0x%08x", vsub->tmsi);
+	else if (vsub->tmsi_new != GSM_RESERVED_TMSI)
+		snprintf(buf, sizeof(buf), "TMSI(new):0x%08x", vsub->tmsi_new);
+	else
+		return "unknown";
+	buf[sizeof(buf)-1] = '\0';
+	return buf;
 }
 
-struct gsm_subscriber *subscr_alloc(void)
+const char *vlr_subscr_msisdn_or_name(struct vlr_subscr *vsub)
 {
-	struct gsm_subscriber *s;
-
-	s = talloc_zero(tall_subscr_ctx, struct gsm_subscriber);
-	if (!s)
-		return NULL;
-
-	llist_add_tail(&s->entry, &active_subscribers);
-	s->use_count = 1;
-	s->tmsi = GSM_RESERVED_TMSI;
-
-	INIT_LLIST_HEAD(&s->requests);
-
-	return s;
-}
-
-static void subscr_free(struct gsm_subscriber *subscr)
-{
-	llist_del(&subscr->entry);
-	talloc_free(subscr);
-}
-
-void subscr_direct_free(struct gsm_subscriber *subscr)
-{
-	OSMO_ASSERT(subscr->use_count == 1);
-	subscr_free(subscr);
-}
-
-struct gsm_subscriber *subscr_get(struct gsm_subscriber *subscr)
-{
-	subscr->use_count++;
-	DEBUGP(DREF, "subscr %s usage increases usage to: %d\n",
-			subscr->extension, subscr->use_count);
-	return subscr;
-}
-
-struct gsm_subscriber *subscr_put(struct gsm_subscriber *subscr)
-{
-	subscr->use_count--;
-	DEBUGP(DREF, "subscr %s usage decreased usage to: %d\n",
-			subscr->extension, subscr->use_count);
-	if (subscr->use_count <= 0 &&
-	    !((subscr->group && subscr->group->keep_subscr) ||
-	      subscr->keep_in_ram))
-		subscr_free(subscr);
-	return NULL;
-}
-
-struct gsm_subscriber *subscr_get_or_create(struct gsm_subscriber_group *sgrp,
-					    const char *imsi)
-{
-	struct gsm_subscriber *subscr;
-
-	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
-		if (strcmp(subscr->imsi, imsi) == 0 && subscr->group == sgrp)
-			return subscr_get(subscr);
-	}
-
-	subscr = subscr_alloc();
-	if (!subscr)
-		return NULL;
-
-	osmo_strlcpy(subscr->imsi, imsi, sizeof(subscr->imsi));
-	subscr->group = sgrp;
-	return subscr;
-}
-
-struct gsm_subscriber *subscr_active_by_tmsi(struct gsm_subscriber_group *sgrp,
-					     uint32_t tmsi)
-{
-	struct gsm_subscriber *subscr;
-
-	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
-		if (subscr->tmsi == tmsi && subscr->group == sgrp)
-			return subscr_get(subscr);
-	}
-
-	return NULL;
-}
-
-struct gsm_subscriber *subscr_active_by_imsi(struct gsm_subscriber_group *sgrp,
-					     const char *imsi)
-{
-	struct gsm_subscriber *subscr;
-
-	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
-		if (strcmp(subscr->imsi, imsi) == 0 && subscr->group == sgrp)
-			return subscr_get(subscr);
-	}
-
-	return NULL;
-}
-
-int subscr_purge_inactive(struct gsm_subscriber_group *sgrp)
-{
-	struct gsm_subscriber *subscr, *tmp;
-	int purged = 0;
-
-	llist_for_each_entry_safe(subscr, tmp, subscr_bsc_active_subscribers(), entry) {
-		if (subscr->group == sgrp && subscr->use_count <= 0) {
-			subscr_free(subscr);
-			purged += 1;
-		}
-	}
-
-	return purged;
+	if (!vsub || !vsub->msisdn[0])
+		return vlr_subscr_name(vsub);
+	return vsub->msisdn;
 }
diff --git a/src/libcommon/gsup_client.c b/src/libcommon/gsup_client.c
index 46f25bb..258f230 100644
--- a/src/libcommon/gsup_client.c
+++ b/src/libcommon/gsup_client.c
@@ -72,12 +72,12 @@
 	rc = ipa_client_conn_open(gsupc->link);
 
 	if (rc >= 0) {
-		LOGP(DLGSUP, LOGL_INFO, "GSUP connecting to %s:%d\n",
+		LOGP(DLGSUP, LOGL_NOTICE, "GSUP connecting to %s:%d\n",
 		     gsupc->link->addr, gsupc->link->port);
 		return 0;
 	}
 
-	LOGP(DLGSUP, LOGL_INFO, "GSUP failed to connect to %s:%d: %s\n",
+	LOGP(DLGSUP, LOGL_ERROR, "GSUP failed to connect to %s:%d: %s\n",
 	     gsupc->link->addr, gsupc->link->port, strerror(-rc));
 
 	if (rc == -EBADF || rc == -ENOTSOCK || rc == -EAFNOSUPPORT ||
@@ -331,11 +331,15 @@
 int gsup_client_send(struct gsup_client *gsupc, struct msgb *msg)
 {
 	if (!gsupc) {
+		LOGP(DGPRS, LOGL_NOTICE, "No GSUP client, unable to "
+			"send %s\n", msgb_hexdump(msg));
 		msgb_free(msg);
 		return -ENOTCONN;
 	}
 
 	if (!gsupc->is_connected) {
+		LOGP(DGPRS, LOGL_NOTICE, "GSUP not connected, unable to "
+			"send %s\n", msgb_hexdump(msg));
 		msgb_free(msg);
 		return -EAGAIN;
 	}
diff --git a/src/libcommon/gsup_test_client.c b/src/libcommon/gsup_test_client.c
index 1b39670..b6a8d6b 100644
--- a/src/libcommon/gsup_test_client.c
+++ b/src/libcommon/gsup_test_client.c
@@ -271,7 +271,7 @@
 {
 	unsigned long long i;
 	char *server_host = "127.0.0.1";
-	uint16_t server_port = 2222;
+	uint16_t server_port = OSMO_GSUP_PORT;
 
 	osmo_init_logging(&gsup_test_client_log_info);