vty/command: fix: restrict the expert mode to the current session

Having the expert mode flag stored in the global 'host' structure
was a bad idea, because this way it applies globally.  In other
words, if user Bob activates the expert mode in his dedicated
session (e.g. a telnet connection), then not only him, but all
other users would see the hidden commands in their VTYs.

Moreover, if somebody deactivates the expert mode, it would also
affect the Bob's VTY session.  And finally, terminating a VTY
session would not deactivate the expert mode.

Let's move that flag from the global 'struct host' to 'struct vty'
representing an individual VTY session, so then the expert mode
would only affect the session where it was activated.

In functions related to the XML VTY reference generation we don't
have access to 'struct vty' (there may be no VTY session at all).
Add two additional arguments to vty_dump_nodes(), indicating the
global flag mask and a matching mode.  This would allow to match
the VTY commands in many different ways, e.g. one can dump hidden
commands only, or all commands except the library specific ones.

Change-Id: Iba13f0949061e3dadf9cf92829d15e97074fe4ad
Related: SYS#4910

1 files changed, 38 insertions, 17 deletions

diff --git a/src/vty/command.c b/src/vty/command.c
index 7ea19712..c233aa6a 100644
--- a/src/vty/command.c
+++ b/src/vty/command.c
@@ -773,8 +773,23 @@ static bool vty_command_is_common(const struct cmd_element *cmd);
 
 /*
  * Dump all nodes and commands associated with a given node as XML via a print_func_t.
+ *
+ * (gflag_mask, match = false) - print only those commands with non-matching flags.
+ * (gflag_mask, match = true) - print only those commands with matching flags.
+ *
+ * Some examples:
+ *
+ *  Print all commands except deprecated and hidden (default mode):
+ *    (CMD_ATTR_DEPRECATED | CMD_ATTR_HIDDEN, false)
+ *  Print only deprecated and hidden commands:
+ *    (CMD_ATTR_DEPRECATED | CMD_ATTR_HIDDEN, true)
+ *  Print all commands except deprecated (expert mode):
+ *    (CMD_ATTR_DEPRECATED, false)
+ *  Print only hidden commands:
+ *    (CMD_ATTR_HIDDEN, true)
  */
-static int vty_dump_nodes(print_func_t print_func, void *data, const char *newline)
+static int vty_dump_nodes(print_func_t print_func, void *data, const char *newline,
+			  unsigned char gflag_mask, bool match)
 {
 	int i, j;
 	int same_name_count;
@@ -797,9 +812,9 @@ static int vty_dump_nodes(print_func_t print_func, void *data, const char *newli
 			const struct cmd_element *elem = vector_slot(cnode->cmd_vector, j);
 			if (!vty_command_is_common(elem))
 				continue;
-			if (elem->attr & CMD_ATTR_DEPRECATED)
+			if (!match && (elem->attr & gflag_mask) != 0x00)
 				continue;
-			if (!host.expert_mode && (elem->attr & CMD_ATTR_HIDDEN))
+			if (match && (elem->attr & gflag_mask) == 0x00)
 				continue;
 			vty_dump_element(elem, print_func, data, newline);
 		}
@@ -835,9 +850,9 @@ static int vty_dump_nodes(print_func_t print_func, void *data, const char *newli
 			const struct cmd_element *elem = vector_slot(cnode->cmd_vector, j);
 			if (vty_command_is_common(elem))
 				continue;
-			if (elem->attr & CMD_ATTR_DEPRECATED)
+			if (!match && (elem->attr & gflag_mask) != 0x00)
 				continue;
-			if (!host.expert_mode && (elem->attr & CMD_ATTR_HIDDEN))
+			if (match && (elem->attr & gflag_mask) == 0x00)
 				continue;
 			vty_dump_element(elem, print_func, data, newline);
 		}
@@ -863,7 +878,10 @@ static int print_func_vty(void *data, const char *format, ...)
 
 static int vty_dump_xml_ref_to_vty(struct vty *vty)
 {
-	return vty_dump_nodes(print_func_vty, vty, VTY_NEWLINE);
+	unsigned char gflag_mask = CMD_ATTR_DEPRECATED;
+	if (!vty->expert_mode)
+		gflag_mask |= CMD_ATTR_HIDDEN;
+	return vty_dump_nodes(print_func_vty, vty, VTY_NEWLINE, gflag_mask, false);
 }
 
 static int print_func_stream(void *data, const char *format, ...)
@@ -895,17 +913,21 @@ const struct value_string vty_ref_gen_mode_desc[] = {
  */
 int vty_dump_xml_ref_mode(FILE *stream, enum vty_ref_gen_mode mode)
 {
+	unsigned char gflag_mask;
+
 	switch (mode) {
 	case VTY_REF_GEN_MODE_EXPERT:
-		host.expert_mode = true;
+		/* All commands except deprecated */
+		gflag_mask = CMD_ATTR_DEPRECATED;
 		break;
 	case VTY_REF_GEN_MODE_DEFAULT:
 	default:
-		host.expert_mode = false;
+		/* All commands except deprecated and hidden */
+		gflag_mask = CMD_ATTR_DEPRECATED | CMD_ATTR_HIDDEN;
 		break;
 	}
 
-	return vty_dump_nodes(print_func_stream, stream, "\n");
+	return vty_dump_nodes(print_func_stream, stream, "\n", gflag_mask, false);
 }
 
 /*! Print the XML reference of all VTY nodes to the given stream.
@@ -2051,7 +2073,7 @@ cmd_describe_command_real(vector vline, struct vty *vty, int *status)
 
 		if (cmd_element->attr & CMD_ATTR_DEPRECATED)
 			continue;
-		if (!host.expert_mode && (cmd_element->attr & CMD_ATTR_HIDDEN))
+		if (!vty->expert_mode && (cmd_element->attr & CMD_ATTR_HIDDEN))
 			continue;
 
 		strvec = cmd_element->strvec;
@@ -2923,7 +2945,7 @@ DEFUN(enable, config_enable_cmd,
 	else
 		vty->node = AUTH_ENABLE_NODE;
 
-	host.expert_mode = argc > 0;
+	vty->expert_mode = argc > 0;
 
 	return CMD_SUCCESS;
 }
@@ -2935,7 +2957,7 @@ DEFUN(disable,
 	if (vty->node == ENABLE_NODE)
 		vty->node = VIEW_NODE;
 
-	host.expert_mode = false;
+	vty->expert_mode = false;
 
 	return CMD_SUCCESS;
 }
@@ -3123,7 +3145,7 @@ gDEFUN(show_vty_attr, show_vty_attr_cmd,
 }
 
 /* Compose flag bit-mask for all commands within the given node */
-static unsigned int node_flag_mask(const struct cmd_node *cnode)
+static unsigned int node_flag_mask(const struct cmd_node *cnode, bool expert_mode)
 {
 	unsigned int flag_mask = 0x00;
 	unsigned int f, i;
@@ -3137,7 +3159,7 @@ static unsigned int node_flag_mask(const struct cmd_node *cnode)
 				continue;
 			if (cmd->attr & CMD_ATTR_DEPRECATED)
 				continue;
-			if (!host.expert_mode && (cmd->attr & CMD_ATTR_HIDDEN))
+			if (!expert_mode && (cmd->attr & CMD_ATTR_HIDDEN))
 				continue;
 			if (~cmd->usrattr & ((unsigned)1 << f))
 				continue;
@@ -3221,14 +3243,14 @@ gDEFUN(config_list, config_list_cmd,
 	struct cmd_element *cmd;
 
 	if (argc > 0)
-		flag_mask = node_flag_mask(cnode);
+		flag_mask = node_flag_mask(cnode, vty->expert_mode);
 
 	for (i = 0; i < vector_active(cnode->cmd_vector); i++) {
 		if ((cmd = vector_slot(cnode->cmd_vector, i)) == NULL)
 			continue;
 		if (cmd->attr & CMD_ATTR_DEPRECATED)
 			continue;
-		if (!host.expert_mode && (cmd->attr & CMD_ATTR_HIDDEN))
+		if (!vty->expert_mode && (cmd->attr & CMD_ATTR_HIDDEN))
 			continue;
 		if (!argc)
 			vty_out(vty, "  %s%s", cmd->string, VTY_NEWLINE);
@@ -4302,7 +4324,6 @@ void cmd_init(int terminal)
 	host.lines = -1;
 	host.motd = default_motd;
 	host.motdfile = NULL;
-	host.expert_mode = false;
 
 	/* Install top nodes. */
 	install_node_bare(&view_node, NULL);