res_pjsip: Add 'ip' as a valid option to 'identify_by' on endpoint.

When the identify_by option on an endpoint is set to ip it will
only be identified using the res_pjsip_endpoint_identifier_ip module.
This ensures that it is not mistakenly matched using the username of
the From header. To ensure behavior has not changed the default has
been changed to "username,ip" for the identify_by option.

ASTERISK-27206

Change-Id: I2170b86a7f7e221b4f00bf14aa1ef1ac5b050bbd

CHANGES

@@ -26,6 +26,16 @@ chan_sip
    headers be retrieved from the REFER message and made accessible to the
    dialplan in the hash TRANSFER_DATA.
 
+------------------------------------------------------------------------------
+--- Functionality changes from Asterisk 15.1.0 to Asterisk 15.2.0 ------------
+------------------------------------------------------------------------------
+
+res_pjsip
+------------------
+ * The "identify_by" on endpoints can now be set to "ip" to restrict an endpoint
+   being matched based only on IP address. To ensure no behavior change the
+   default has been changed to "username,ip".
+
 ------------------------------------------------------------------------------
 --- Functionality changes from Asterisk 15.0.0 to Asterisk 15.1.0 ------------
 ------------------------------------------------------------------------------

configs/samples/pjsip.conf.sample

@@ -634,9 +634,11 @@
                         ; identified.
                         ; "username": Identify by the From or To username and domain
                         ; "auth_username": Identify by the Authorization username and realm
-                        ; In all cases, if an exact match on username and domain/realm fails,
-                        ; the match will be retried with just the username.
-                        ; (default: "username")
+                        ; "ip": Identify by the source IP address
+                        ; In username and auth_username cases, if an exact match on
+                        ; username and domain/realm fails, the match will be retried
+                        ; with just the username.
+                        ; (default: "username,ip")
 ;redirect_method=user   ; How redirects received from an endpoint are handled
                         ; (default: "user")
 ;mailboxes=     ; NOTIFY the endpoint when state changes for any of the specified mailboxes.

contrib/ast-db-manage/config/versions/20abce6d1e3c_add_pjsip_identify_by_ip.py

@@ -0,0 +1,46 @@
+"""add pjsip identify by ip
+
+Revision ID: 20abce6d1e3c
+Revises: a1698e8bb9c5
+Create Date: 2017-10-24 15:44:06.404774
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '20abce6d1e3c'
+down_revision = 'a1698e8bb9c5'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def enum_update(table_name, column_name, enum_name, enum_values):
+    if op.get_context().bind.dialect.name != 'postgresql':
+        if op.get_context().bind.dialect.name == 'mssql':
+            op.drop_constraint('ck_ps_endpoints_identify_by_pjsip_identify_by_values', 'ps_endpoints')
+        op.alter_column(table_name, column_name,
+                        type_=sa.Enum(*enum_values, name=enum_name))
+        return
+
+    # Postgres requires a few more steps
+    tmp = enum_name + '_tmp'
+
+    op.execute('ALTER TYPE ' + enum_name + ' RENAME TO ' + tmp)
+
+    updated = sa.Enum(*enum_values, name=enum_name)
+    updated.create(op.get_bind(), checkfirst=False)
+
+    op.execute('ALTER TABLE ' + table_name + ' ALTER COLUMN ' + column_name +
+               ' TYPE ' + enum_name + ' USING identify_by::text::' + enum_name)
+
+    op.execute('DROP TYPE ' + tmp)
+
+
+def upgrade():
+    enum_update('ps_endpoints', 'identify_by', 'pjsip_identify_by_values',
+                ['username', 'auth_username', 'ip'])
+
+
+def downgrade():
+    enum_update('ps_endpoints', 'identify_by', 'pjsip_identify_by_values',
+                ['username', 'auth_username'])

include/asterisk/res_pjsip.h

@@ -437,6 +437,8 @@ enum ast_sip_endpoint_identifier_type {
 	AST_SIP_ENDPOINT_IDENTIFY_BY_USERNAME = (1 << 0),
 	/*! Identify based on user name in Auth header first, then From header */
 	AST_SIP_ENDPOINT_IDENTIFY_BY_AUTH_USERNAME = (1 << 1),
+	/*! Identify based on source IP address */
+	AST_SIP_ENDPOINT_IDENTIFY_BY_IP = (1 << 2),
 };
 AST_VECTOR(ast_sip_identify_by_vector, enum ast_sip_endpoint_identifier_type);
 

res/res_pjsip.c

@@ -268,15 +268,17 @@
 				<configOption name="ice_support" default="no">
 					<synopsis>Enable the ICE mechanism to help traverse NAT</synopsis>
 				</configOption>
-				<configOption name="identify_by" default="username,location">
+				<configOption name="identify_by" default="username,ip">
 					<synopsis>Way(s) for Endpoint to be identified</synopsis>
 					<description><para>
 						Endpoints and aors can be identified in multiple ways. Currently, the supported
 						options are <literal>username</literal>, which matches the endpoint or aor id based on
-						the username and domain in the From header (or To header for aors), and
+						the username and domain in the From header (or To header for aors),
 						<literal>auth_username</literal>, which matches the endpoint or aor id based on the
-						username and realm in the Authentication header.  In all cases, if an exact match
-						on both username and domain/realm fails, the match will be retried with just the username.
+						username and realm in the Authentication header, and <literal>ip</literal> which matches
+						an endpoint based on the source IP address.  In the <literal>username</literal> and
+						<literal>auth_username</literal> cases, if an exact match on both username and
+						domain/realm fails, the match will be retried with just the username.
 						</para>
 						<note><para>
 						Identification by auth_username has some security considerations because an
@@ -292,14 +294,19 @@
 						configuration object.
 						</para></note>
 						<note><para>Endpoints can also be identified by IP address; however, that method
-						of identification is not handled by this configuration option. See the documentation
-						for the <literal>identify</literal> configuration section for more details on that
-						method of endpoint identification. If this option is set and an <literal>identify</literal>
-						configuration section exists for the endpoint, then the endpoint can be identified in
-						multiple ways.</para></note>
+						of identification is not configured but simply allowed by this configuration option.
+						See the documentation for the <literal>identify</literal> configuration section for
+						more details on that method of endpoint identification.</para></note>
+						<note><para>
+						This option controls both how an endpoint is matched for incoming traffic and also how
+						an AoR is determined if a registration occurs. If <literal>ip</literal> is set alone
+						then incoming registration will not find an AoR and the registration attempt will fail.
+						If you want to allow incoming registrations to succeed you must set a second identify
+						method such as <literal>username</literal> in this case.</para></note>
 						<enumlist>
 							<enum name="username" />
 							<enum name="auth_username" />
+							<enum name="ip" />
 						</enumlist>
 					</description>
 				</configOption>

res/res_pjsip/pjsip_configuration.c

@@ -584,6 +584,8 @@ static int ident_handler(const struct aco_option *opt, struct ast_variable *var,
 			method = AST_SIP_ENDPOINT_IDENTIFY_BY_USERNAME;
 		} else if (!strcasecmp(val, "auth_username")) {
 			method = AST_SIP_ENDPOINT_IDENTIFY_BY_AUTH_USERNAME;
+		} else if (!strcasecmp(val, "ip")) {
+			method = AST_SIP_ENDPOINT_IDENTIFY_BY_IP;
 		} else {
 			ast_log(LOG_ERROR, "Unrecognized identification method %s specified for endpoint %s\n",
 					val, ast_sorcery_object_get_id(endpoint));
@@ -628,6 +630,9 @@ static int ident_to_str(const void *obj, const intptr_t *args, char **buf)
 		case AST_SIP_ENDPOINT_IDENTIFY_BY_AUTH_USERNAME :
 			method = "auth_username";
 			break;
+		case AST_SIP_ENDPOINT_IDENTIFY_BY_IP :
+			method = "ip";
+			break;
 		default:
 			continue;
 		}
@@ -1901,7 +1906,7 @@ int ast_res_pjsip_initialize_configuration(void)
 	ast_sorcery_object_field_register(sip_sorcery, "endpoint", "aors", "", OPT_STRINGFIELD_T, 0, STRFLDSET(struct ast_sip_endpoint, aors));
 	ast_sorcery_object_field_register(sip_sorcery, "endpoint", "media_address", "", OPT_STRINGFIELD_T, 0, STRFLDSET(struct ast_sip_endpoint, media.address));
 	ast_sorcery_object_field_register(sip_sorcery, "endpoint", "bind_rtp_to_media_address", "no", OPT_BOOL_T, 1, STRFLDSET(struct ast_sip_endpoint, media.bind_rtp_to_media_address));
-	ast_sorcery_object_field_register_custom(sip_sorcery, "endpoint", "identify_by", "username", ident_handler, ident_to_str, NULL, 0, 0);
+	ast_sorcery_object_field_register_custom(sip_sorcery, "endpoint", "identify_by", "username,ip", ident_handler, ident_to_str, NULL, 0, 0);
 	ast_sorcery_object_field_register(sip_sorcery, "endpoint", "direct_media", "yes", OPT_BOOL_T, 1, FLDSET(struct ast_sip_endpoint, media.direct_media.enabled));
 	ast_sorcery_object_field_register_custom(sip_sorcery, "endpoint", "direct_media_method", "invite", direct_media_method_handler, direct_media_method_to_str, NULL, 0, 0);
 	ast_sorcery_object_field_register_custom(sip_sorcery, "endpoint", "connected_line_method", "invite", connected_line_method_handler, connected_line_method_to_str, NULL, 0, 0);

res/res_pjsip_endpoint_identifier_ip.c

@@ -227,7 +227,14 @@ static struct ast_sip_endpoint *ip_identify(pjsip_rx_data *rdata)
 	}
 
 	endpoint = ast_sorcery_retrieve_by_id(ast_sip_get_sorcery(), "endpoint", match->endpoint_name);
+
 	if (endpoint) {
+		if (!(endpoint->ident_method & AST_SIP_ENDPOINT_IDENTIFY_BY_IP)) {
+			ast_debug(3, "Endpoint '%s' found for '%s' but 'ip' method not supported'\n", match->endpoint_name,
+				ast_sockaddr_stringify(&addr));
+			ao2_cleanup(endpoint);
+			return NULL;
+		}
 		ast_debug(3, "Retrieved endpoint %s\n", ast_sorcery_object_get_id(endpoint));
 	} else {
 		ast_log(LOG_WARNING, "Identify section '%s' points to endpoint '%s' but endpoint could not be looked up\n",