VTY: alloc/dealloc/show imsi pseudo

Create VTY commands and related database functions to get, allocate and
deallocate pseudonymous IMSIs. As this is a proof of concept, the code
to retrieve the next pseudonymous IMSI has no performance optimizations
and might not use a good entropy source (I did not verify).

Related: OS#4476
Change-Id: Ia93ee58d5e03c801eb774b9483a9a4417d031959

13 files changed, 345 insertions, 0 deletions

diff --git a/include/osmocom/hlr/Makefile.am b/include/osmocom/hlr/Makefile.am
index aceda4a..876c97f 100644
--- a/include/osmocom/hlr/Makefile.am
+++ b/include/osmocom/hlr/Makefile.am
@@ -9,6 +9,7 @@ noinst_HEADERS = \
 	hlr_ussd.h \
 	hlr_vty.h \
 	hlr_vty_subscr.h \
+	imsi_pseudo.h \
 	logging.h \
 	lu_fsm.h \
 	mslookup_server.h \
diff --git a/include/osmocom/hlr/db.h b/include/osmocom/hlr/db.h
index ca336a0..abb7357 100644
--- a/include/osmocom/hlr/db.h
+++ b/include/osmocom/hlr/db.h
@@ -33,6 +33,10 @@ enum stmt_idx {
 	DB_STMT_SET_LAST_LU_SEEN_PS,
 	DB_STMT_EXISTS_BY_IMSI,
 	DB_STMT_EXISTS_BY_MSISDN,
+	DB_STMT_PSEUDO_BY_ID,
+	DB_STMT_PSEUDO_INSERT,
+	DB_STMT_PSEUDO_DELETE,
+	DB_STMT_PSEUDO_NEXT,
 	_NUM_DB_STMT
 };
 
diff --git a/include/osmocom/hlr/imsi_pseudo.h b/include/osmocom/hlr/imsi_pseudo.h
new file mode 100644
index 0000000..e1118c3
--- /dev/null
+++ b/include/osmocom/hlr/imsi_pseudo.h
@@ -0,0 +1,19 @@
+#pragma once
+
+#include <stdint.h>
+#include <inttypes.h>
+#include <osmocom/hlr/db.h>
+
+#define LOGPSEUDO(id, level, fmt, args ...) LOGP(DPSEUDO, level, "subscriber_id='%" PRId64 "': " fmt, id, ## args)
+
+struct imsi_pseudo_data {
+	int alloc_count; /* 0: none, 1: only current is allocated, 2: current and previous are allocated */
+	int64_t i; /* current imsi_pseudo_i */
+	char current[GSM23003_IMSI_MAX_DIGITS+1];
+	char previous[GSM23003_IMSI_MAX_DIGITS+1];
+};
+
+int db_get_imsi_pseudo_data(struct db_context *dbc, int64_t subscr_id, struct imsi_pseudo_data *data);
+int db_alloc_imsi_pseudo(struct db_context *dbc, int64_t subscr_id, const char *imsi_pseudo, int64_t imsi_pseudo_i);
+int db_dealloc_imsi_pseudo(struct db_context *dbc, const char *imsi_pseudo);
+int db_get_imsi_pseudo_next(struct db_context *dbc, char *imsi_pseudo);
diff --git a/include/osmocom/hlr/logging.h b/include/osmocom/hlr/logging.h
index a8081af..5be21a5 100644
--- a/include/osmocom/hlr/logging.h
+++ b/include/osmocom/hlr/logging.h
@@ -8,6 +8,7 @@ enum {
 	DGSUP,
 	DAUC,
 	DSS,
+	DPSEUDO,
 	DMSLOOKUP,
 	DLU,
 	DDGSM,
diff --git a/src/Makefile.am b/src/Makefile.am
index 09e9101..49b50f4 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -44,6 +44,7 @@ osmo_hlr_SOURCES = \
 	db.c \
 	db_auc.c \
 	db_hlr.c \
+	db_imsi_pseudo.c \
 	gsup_router.c \
 	gsup_server.c \
 	hlr.c \
diff --git a/src/db.c b/src/db.c
index 325b63a..2949d2f 100644
--- a/src/db.c
+++ b/src/db.c
@@ -85,6 +85,23 @@ static const char *stmt_sql[] = {
 	[DB_STMT_SET_LAST_LU_SEEN_PS] = "UPDATE subscriber SET last_lu_seen_ps = datetime($val, 'unixepoch') WHERE id = $subscriber_id",
 	[DB_STMT_EXISTS_BY_IMSI] = "SELECT 1 FROM subscriber WHERE imsi = $imsi",
 	[DB_STMT_EXISTS_BY_MSISDN] = "SELECT 1 FROM subscriber WHERE msisdn = $msisdn",
+	[DB_STMT_PSEUDO_BY_ID] =
+		"SELECT imsi_pseudo, imsi_pseudo_i"
+		" FROM subscriber_imsi_pseudo"
+		" WHERE subscriber_id = $subscriber_id"
+		" ORDER BY imsi_pseudo_i DESC",
+	[DB_STMT_PSEUDO_INSERT] =
+		"INSERT INTO subscriber_imsi_pseudo (subscriber_id, imsi_pseudo, imsi_pseudo_i)"
+		" VALUES($subscriber_id, $imsi_pseudo, $imsi_pseudo_i)",
+	[DB_STMT_PSEUDO_DELETE] =
+		"DELETE FROM subscriber_imsi_pseudo WHERE imsi_pseudo = $imsi_pseudo",
+	[DB_STMT_PSEUDO_NEXT] = /* Proof of concept! Verify performance and entropy usage before using in real world! */
+		"SELECT imsi"
+		" FROM subscriber"
+		" LEFT JOIN subscriber_imsi_pseudo ON imsi = imsi_pseudo"
+		" WHERE imsi_pseudo IS NULL"
+		" ORDER BY RANDOM()"
+		" LIMIT 1",
 };
 
 static void sql3_error_log_cb(void *arg, int err_code, const char *msg)
diff --git a/src/db_imsi_pseudo.c b/src/db_imsi_pseudo.c
new file mode 100644
index 0000000..d1c09ab
--- /dev/null
+++ b/src/db_imsi_pseudo.c
@@ -0,0 +1,143 @@
+/* (C) 2020 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <errno.h>
+#include <inttypes.h>
+
+#include <sqlite3.h>
+
+#include <osmocom/hlr/logging.h>
+#include <osmocom/hlr/db.h>
+#include <osmocom/hlr/imsi_pseudo.h>
+
+int db_get_imsi_pseudo_data(struct db_context *dbc, int64_t subscr_id, struct imsi_pseudo_data *data)
+{
+	sqlite3_stmt *stmt = dbc->stmt[DB_STMT_PSEUDO_BY_ID];
+	int i, rc, ret = 0;
+
+	memset(data, 0, sizeof(*data));
+
+	if (!db_bind_int64(stmt, "$subscriber_id", subscr_id))
+		return -EIO;
+
+	/* Retrieve up to two allocated pseudo IMSIs in three sqlite3 steps */
+	for (i = 0; i < 3; i++) {
+		rc = sqlite3_step(stmt);
+		switch (rc) {
+		case SQLITE_ROW:
+			data->alloc_count = i + 1;
+			switch (i) {
+			case 0:
+				/* First entry is always current (ORDER BY in SQL statement) */
+				copy_sqlite3_text_to_buf(data->current, stmt, 0);
+				data->i = sqlite3_column_int(stmt, 1);
+				break;
+			case 1:
+				copy_sqlite3_text_to_buf(data->previous, stmt, 0);
+				break;
+			case 2:
+				LOGPSEUDO(subscr_id, LOGL_ERROR, "more than two pseudonymous IMSI allocated\n");
+				ret = -EINVAL;
+				goto out;
+			}
+			break;
+		case SQLITE_DONE:
+			goto out;
+		default:
+			LOGPSEUDO(subscr_id, LOGL_ERROR, "error executing SQL: %d\n", rc);
+			ret = -EIO;
+			goto out;
+		}
+	}
+out:
+	db_remove_reset(stmt);
+	return ret;
+}
+
+int db_alloc_imsi_pseudo(struct db_context *dbc, int64_t subscr_id, const char *imsi_pseudo, int64_t imsi_pseudo_i)
+{
+	sqlite3_stmt *stmt = dbc->stmt[DB_STMT_PSEUDO_INSERT];
+	int rc, ret = 0;
+
+	if (!db_bind_int64(stmt, "$subscriber_id", subscr_id))
+		return -EIO;
+	if (!db_bind_text(stmt, "$imsi_pseudo", imsi_pseudo))
+		return -EIO;
+	if (!db_bind_int64(stmt, "$imsi_pseudo_i", imsi_pseudo_i))
+		return -EIO;
+
+	rc = sqlite3_step(stmt);
+	if (rc != SQLITE_DONE) {
+		LOGPSEUDO(subscr_id, LOGL_ERROR, "imsi_pseudo='%s', imsi_pseudo_i='%" PRId64 "': SQL error during"
+			  " allocate: %d\n", imsi_pseudo, imsi_pseudo_i, rc);
+		ret = -EIO;
+	}
+	db_remove_reset(stmt);
+	return ret;
+}
+
+int db_dealloc_imsi_pseudo(struct db_context *dbc, const char *imsi_pseudo)
+{
+	sqlite3_stmt *stmt = dbc->stmt[DB_STMT_PSEUDO_DELETE];
+	int rc, ret = 0;
+
+	if (!db_bind_text(stmt, "$imsi_pseudo", imsi_pseudo))
+		return -EIO;
+
+	rc = sqlite3_step(stmt);
+	if (rc != SQLITE_DONE) {
+		LOGP(DPSEUDO, LOGL_ERROR, "imsi_pseudo='%s': SQL error during deallocate: %d\n", imsi_pseudo, rc);
+		ret = -EIO;
+	}
+
+	db_remove_reset(stmt);
+	return ret;
+}
+
+/*! Get the next random free pseudo IMSI.
+ *  \param[in] dbc database context.
+ *  \param[out] imsi_pseudo buffer with length GSM23003_IMSI_MAX_DIGITS+1.
+ *  \returns 0: success, -1: no next IMSI available, -2: SQL error. */
+int db_get_imsi_pseudo_next(struct db_context *dbc, char *imsi_pseudo)
+{
+	sqlite3_stmt *stmt = dbc->stmt[DB_STMT_PSEUDO_NEXT];
+	const char *imsi;
+	int rc, ret = 0;
+
+	rc = sqlite3_step(stmt);
+	switch (rc) {
+	case SQLITE_ROW:
+		/* Can't use copy_sqlite3_text_to_buf, as it assumes the wrong size for imsi_pseudo */
+		imsi = (const char *)sqlite3_column_text(stmt, 0);
+		osmo_strlcpy(imsi_pseudo, imsi, GSM23003_IMSI_MAX_DIGITS+1);
+		break;
+	case SQLITE_DONE:
+		LOGP(DPSEUDO, LOGL_ERROR, "failed to get next pseudonymous IMSI: all IMSIs are already allocated as"
+					  " pseudo IMSI\n");
+		ret = -1;
+		break;
+	default:
+		LOGP(DPSEUDO, LOGL_ERROR, "failed to get next pseudonymous IMSI, SQL error: %d\n", rc);
+		ret = -2;
+		break;
+	}
+
+	db_remove_reset(stmt);
+	return ret;
+}
diff --git a/src/hlr_vty_subscr.c b/src/hlr_vty_subscr.c
index a9262ba..58094fb 100644
--- a/src/hlr_vty_subscr.c
+++ b/src/hlr_vty_subscr.c
@@ -31,6 +31,7 @@
 #include <osmocom/hlr/hlr.h>
 #include <osmocom/hlr/db.h>
 #include <osmocom/hlr/timestamp.h>
+#include <osmocom/hlr/imsi_pseudo.h>
 
 struct vty;
 
@@ -69,6 +70,18 @@ static void dump_last_lu_seen(struct vty *vty, const char *domain_label, time_t
 	}
 }
 
+static void dump_imsi_pseudo(struct vty *vty, struct hlr_subscriber *subscr)
+{
+	struct imsi_pseudo_data data;
+
+	if (db_get_imsi_pseudo_data(g_hlr->dbc, subscr->id, &data) != 0)
+		return;
+	if (data.alloc_count >= 1)
+		vty_out(vty, "    Pseudonymous IMSI (current): %s, i: %" PRId64 "%s", data.current, data.i, VTY_NEWLINE);
+	if (data.alloc_count == 2)
+		vty_out(vty, "    Pseudonymous IMSI (previous): %s%s", data.previous, VTY_NEWLINE);
+}
+
 static void subscr_dump_full_vty(struct vty *vty, struct hlr_subscriber *subscr)
 {
 	int rc;
@@ -78,6 +91,7 @@ static void subscr_dump_full_vty(struct vty *vty, struct hlr_subscriber *subscr)
 	vty_out(vty, "    ID: %"PRIu64"%s", subscr->id, VTY_NEWLINE);
 
 	vty_out(vty, "    IMSI: %s%s", *subscr->imsi ? subscr->imsi : "none", VTY_NEWLINE);
+	dump_imsi_pseudo(vty, subscr);
 	vty_out(vty, "    MSISDN: %s%s", *subscr->msisdn ? subscr->msisdn : "none", VTY_NEWLINE);
 
 	if (*subscr->imei) {
@@ -203,6 +217,7 @@ static int get_subscr_by_argv(struct vty *vty, const char *type, const char *id,
 #define SUBSCR_UPDATE		SUBSCR "update "
 #define SUBSCR_UPDATE_HELP	SUBSCR_HELP "Set or update subscriber data\n"
 #define SUBSCR_MSISDN_HELP	"Set MSISDN (phone number) of the subscriber\n"
+#define SUBSCR_IMSI_PSEUDO_HELP "Allocate or deallocate pseudonymous IMSI of the subscriber\n"
 
 DEFUN(subscriber_show,
       subscriber_show_cmd,
@@ -625,6 +640,85 @@ DEFUN(subscriber_nam,
 	return CMD_SUCCESS;
 }
 
+DEFUN(subscriber_imsi_pseudo_alloc,
+      subscriber_imsi_pseudo_alloc_cmd,
+      SUBSCR_UPDATE "imsi-pseudo alloc",
+      SUBSCR_UPDATE_HELP
+      SUBSCR_IMSI_PSEUDO_HELP
+      "Allocate a new pseudonymous IMSI (max. 2)\n")
+{
+	struct hlr_subscriber subscr;
+	struct imsi_pseudo_data pseudo;
+	const char *id_type = argv[0];
+	const char *id = argv[1];
+	char imsi_pseudo[GSM23003_IMSI_MAX_DIGITS+1];
+	int rc;
+
+	if (get_subscr_by_argv(vty, id_type, id, &subscr))
+		return CMD_WARNING;
+
+	if (db_get_imsi_pseudo_data(g_hlr->dbc, subscr.id, &pseudo) != 0)
+		return CMD_WARNING;
+
+	if (pseudo.alloc_count == 2) {
+		vty_out(vty, "%% Error: subscriber already has two pseudonymous IMSI allocated%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	rc = db_get_imsi_pseudo_next(g_hlr->dbc, imsi_pseudo);
+	switch (rc) {
+	case -1:
+		vty_out(vty, "%% Error: all IMSIs are already allocated as pseudonymous IMSI%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	case -2:
+		vty_out(vty, "%% Error: failed to get next pseudonymous IMSI (SQL error)%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	if (db_alloc_imsi_pseudo(g_hlr->dbc, subscr.id, imsi_pseudo, pseudo.i + 1) != 0) {
+		vty_out(vty, "%% Error: failed to allocate pseudonymous IMSI '%s'%s", imsi_pseudo, VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	vty_out(vty, "%% New pseudonymous IMSI allocated: %s%s", imsi_pseudo, VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
+DEFUN(subscriber_imsi_pseudo_dealloc,
+      subscriber_imsi_pseudo_dealloc_cmd,
+      SUBSCR_UPDATE "imsi-pseudo dealloc IMSI_PSEUDO",
+      SUBSCR_UPDATE_HELP
+      SUBSCR_IMSI_PSEUDO_HELP
+      "Deallocate a pseudonymous IMSI\n"
+      "Pseudonymous IMSI to deallocate\n")
+{
+	struct hlr_subscriber subscr;
+	struct imsi_pseudo_data pseudo;
+	const char *id_type = argv[0];
+	const char *id = argv[1];
+	const char *imsi_pseudo = argv[2];
+
+	if (get_subscr_by_argv(vty, id_type, id, &subscr))
+		return CMD_WARNING;
+
+	if (db_get_imsi_pseudo_data(g_hlr->dbc, subscr.id, &pseudo) != 0)
+		return CMD_WARNING;
+
+	if ((pseudo.alloc_count >= 1 && strcmp(imsi_pseudo, pseudo.current) == 0) ||
+	    (pseudo.alloc_count == 2 && strcmp(imsi_pseudo, pseudo.previous) == 0)) {
+		/* Pseudonymous IMSI is allocated for given subscriber */
+		if (db_dealloc_imsi_pseudo(g_hlr->dbc, imsi_pseudo) != 0) {
+			vty_out(vty, "Failed to deallocate pseudonymous IMSI%s", VTY_NEWLINE);
+			return CMD_WARNING;
+		}
+	} else {
+		vty_out(vty, "%% Error: pseudonymous IMSI '%s' is not allocated to given subscriber%s", imsi_pseudo,
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	return CMD_SUCCESS;
+}
 
 void hlr_vty_subscriber_init(void)
 {
@@ -639,4 +733,6 @@ void hlr_vty_subscriber_init(void)
 	install_element(ENABLE_NODE, &subscriber_aud3g_cmd);
 	install_element(ENABLE_NODE, &subscriber_imei_cmd);
 	install_element(ENABLE_NODE, &subscriber_nam_cmd);
+	install_element(ENABLE_NODE, &subscriber_imsi_pseudo_alloc_cmd);
+	install_element(ENABLE_NODE, &subscriber_imsi_pseudo_dealloc_cmd);
 }
diff --git a/src/logging.c b/src/logging.c
index eab0510..6302ba2 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -25,6 +25,12 @@ const struct log_info_cat hlr_log_info_cat[] = {
 		.color = "\033[1;34m",
 		.enabled = 1, .loglevel = LOGL_NOTICE,
 	},
+	[DPSEUDO] = {
+		.name = "DPSEUDO",
+		.description = "IMSI Pseudonymization",
+		.color = "\033[1;36m",
+		.enabled = 1, .loglevel = LOGL_NOTICE,
+	},
 	[DMSLOOKUP] = {
 		.name = "DMSLOOKUP",
 		.description = "Mobile Subscriber Lookup",
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9015494..e3588ba 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -45,6 +45,7 @@ if ENABLE_EXT_TESTS
 python-tests:
 # don't run vty and ctrl tests concurrently so that the ports don't conflict
 	$(MAKE) vty-test
+	$(MAKE) vty-test-imsi-pseudo
 	$(MAKE) ctrl-test
 	$(MAKE) db-upgrade-equivalence-test
 else
@@ -68,6 +69,16 @@ vty-test:
 		$(U) $(srcdir)/$(VTY_TEST)
 	-rm -f $(VTY_TEST_DB) $(VTY_TEST_DB)-*
 
+# IMSI pseudon VTY tests: don't share the DB with other VTY tests, so we can have deterministic "random" pseudo IMSIs
+vty-test-imsi-pseudo:
+	-rm -f $(VTY_TEST_DB)
+	sqlite3 $(VTY_TEST_DB) < $(top_srcdir)/sql/hlr.sql
+	osmo_verify_transcript_vty.py -v \
+		-n OsmoHLR -p 4258 \
+		-r "$(top_builddir)/src/osmo-hlr -c $(top_srcdir)/doc/examples/osmo-hlr.cfg -l $(VTY_TEST_DB)" \
+		$(U) $(srcdir)/imsi_pseudo/imsi_pseudo.vty
+	-rm -f $(VTY_TEST_DB) $(VTY_TEST_DB)-*
+
 CTRL_TEST_DB = hlr_ctrl_test.db
 
 # To update the CTRL script from current application behavior,
diff --git a/tests/imsi_pseudo/imsi_pseudo.vty b/tests/imsi_pseudo/imsi_pseudo.vty
new file mode 100644
index 0000000..4709edb
--- /dev/null
+++ b/tests/imsi_pseudo/imsi_pseudo.vty
@@ -0,0 +1,42 @@
+OsmoHLR> enable
+OsmoHLR# subscriber imsi 111111111111111 create
+...
+OsmoHLR# subscriber id 1 update imsi-pseudo alloc
+% New pseudonymous IMSI allocated: 111111111111111
+OsmoHLR# subscriber imsi 222222222222222 create
+...
+OsmoHLR# subscriber id 1 update imsi-pseudo alloc
+% New pseudonymous IMSI allocated: 222222222222222
+OsmoHLR# subscriber id 1 update imsi-pseudo dealloc 111111111111111
+OsmoHLR# subscriber id 2 update imsi-pseudo alloc
+% New pseudonymous IMSI allocated: 111111111111111
+OsmoHLR# subscriber imsi 333333333333333 create
+...
+OsmoHLR# subscriber id 1 update imsi-pseudo alloc
+% New pseudonymous IMSI allocated: 333333333333333
+OsmoHLR# subscriber id 1 show
+    ID: 1
+    IMSI: 111111111111111
+    Pseudonymous IMSI (current): 333333333333333, i: 3
+    Pseudonymous IMSI (previous): 222222222222222
+    MSISDN: none
+OsmoHLR# subscriber id 2 show
+    ID: 2
+    IMSI: 222222222222222
+    Pseudonymous IMSI (current): 111111111111111, i: 1
+    MSISDN: none
+OsmoHLR# subscriber id 3 show
+    ID: 3
+    IMSI: 333333333333333
+    MSISDN: none
+
+OsmoHLR# subscriber id 3 update imsi-pseudo alloc
+% Error: all IMSIs are already allocated as pseudonymous IMSI
+
+OsmoHLR# subscriber id 1 update imsi-pseudo dealloc 123
+% Error: pseudonymous IMSI '123' is not allocated to given subscriber
+
+OsmoHLR# subscriber imsi 444444444444444 create
+...
+OsmoHLR# subscriber id 1 update imsi-pseudo alloc
+% Error: subscriber already has two pseudonymous IMSI allocated
diff --git a/tests/test_nodes.vty b/tests/test_nodes.vty
index 4995f85..7507c8f 100644
--- a/tests/test_nodes.vty
+++ b/tests/test_nodes.vty
@@ -93,6 +93,7 @@ log stderr
  logging level db notice
  logging level auc notice
  logging level ss info
+ logging level pseudo notice
  logging level mslookup notice
  logging level lu notice
  logging level dgsm notice
diff --git a/tests/test_subscriber.vty b/tests/test_subscriber.vty
index fb5da0e..a22641e 100644
--- a/tests/test_subscriber.vty
+++ b/tests/test_subscriber.vty
@@ -13,6 +13,8 @@ OsmoHLR# list
   subscriber (imsi|msisdn|id|imei) IDENT update aud3g milenage k K (op|opc) OP_C [ind-bitlen] [<0-28>]
   subscriber (imsi|msisdn|id|imei) IDENT update imei (none|IMEI)
   subscriber (imsi|msisdn|id|imei) IDENT update network-access-mode (none|cs|ps|cs+ps)
+  subscriber (imsi|msisdn|id|imei) IDENT update imsi-pseudo alloc
+  subscriber (imsi|msisdn|id|imei) IDENT update imsi-pseudo dealloc IMSI_PSEUDO
   show mslookup services
 
 OsmoHLR# subscriber?
@@ -132,6 +134,7 @@ OsmoHLR# subscriber imsi 123456789023000 update ?
   aud3g                Set UMTS authentication data (3G, and 2G with UMTS AKA)
   imei                 Set IMEI of the subscriber (normally populated from MSC, no need to set this manually)
   network-access-mode  Set Network Access Mode (NAM) of the subscriber
+  imsi-pseudo          Allocate or deallocate pseudonymous IMSI of the subscriber
 
 OsmoHLR# subscriber imsi 123456789023000 update msisdn ?
   none    Remove MSISDN (phone number)