message-tags: facility to manipulate client-tags

It provides for hook facilities to client-only tags:

- messages can be dropped silently ;
- messages can be edited ;
- messages can be stripped from a client-only tag

include/client_tags.h

@@ -32,9 +32,15 @@
 #ifndef INCLUDED_client_tags_h
 #define INCLUDED_client_tags_h
 
-// TODO: uniformize this
-struct entity;
+#define MAX_CLIENT_TAGS 100
+#define CLIENT_TAG_MAX_LENGTH 100
 
-extern int accept_client_tag(const char *, const char*, struct entity*);
+struct client_tag_support {
+	char name[CLIENT_TAG_MAX_LENGTH];
+};
+
+extern int add_client_tag(const char *);
+extern void remove_client_tag(const char *);
+extern void format_client_tags(char *, size_t, const char *, const char *);
 
 #endif /* INCLUDED_client_tags_h */

include/hook.h

@@ -47,6 +47,7 @@ extern int h_outbound_msgbuf;
 extern int h_rehash;
 extern int h_priv_change;
 extern int h_cap_change;
+extern int h_client_tag_accept;
 
 void init_hook(void);
 int register_hook(const char *name);
@@ -156,6 +157,14 @@ typedef struct
 	int del;
 } hook_data_cap_change;
 
+typedef struct
+{
+	struct Client *client;
+	struct MsgBuf *outgoing_msgbuf;
+	const struct MsgTag *incoming_tag;
+	bool drop;
+} hook_data_client_tag_accept;
+
 enum message_type {
 	MESSAGE_TYPE_NOTICE,
 	MESSAGE_TYPE_PRIVMSG,

include/msgbuf.h

@@ -77,6 +77,12 @@ struct MsgBuf_cache {
  */
 int msgbuf_parse(struct MsgBuf *msgbuf, char *line);
 
+/*
+ * Parse partially a msgbuf without tags
+ * assuming msgbuf is already initialized.
+ */
+int msgbuf_partial_parse(struct MsgBuf *msgbuf, char *line);
+
 /*
  * Unparse the tail of a msgbuf perfectly, preserving framing details
  * msgbuf->para[n] will reach to the end of the line

ircd/client_tags.c

@@ -32,9 +32,55 @@
 #include "stdinc.h"
 #include "client_tags.h"
 
+struct client_tag_support *supported_client_tags;
+size_t num_client_tags = 0;
+size_t max_client_tags = MAX_CLIENT_TAGS;
+
+void
+init_client_tags(void)
+{
+	supported_client_tags = rb_malloc(sizeof(struct client_tag_support) * MAX_CLIENT_TAGS);
+}
+
 int
-accept_client_tag(const char* tag_key, const char* tag_value, struct entity* target)
+add_client_tag(const char *name)
+{
+	int i;
+
+	if (num_client_tags >= max_client_tags)
+		return -1;
+
+	strcpy(supported_client_tags[num_client_tags].name, name);
+	num_client_tags++;
+
+	return num_client_tags - 1;
+}
+
+void
+remove_client_tag(const char *name)
 {
-	return (1); // accepts
-	return (0); // refuses
+	for (size_t index = 0 ; index < num_client_tags ; index++)
+	{
+		if (strcmp(supported_client_tags[index].name, name)) {
+			strcpy(supported_client_tags[index].name, supported_client_tags[num_client_tags - 1].name);
+			num_client_tags--;
+			break;
+		}
+	}
+}
+
+void
+format_client_tags(char *dst, size_t dst_sz, const char *individual_fmt, const char *join_sep)
+{
+	size_t start = 0;
+	for (size_t index = 0 ; index < num_client_tags ; index++) {
+		if (start >= dst_sz)
+			break;
+
+		if (index > 0) {
+			dst[start] = ',';
+			start++;
+		}
+		start += snprintf((dst + start), dst_sz - start, individual_fmt, supported_client_tags[index].name);
+	}
 }

ircd/hook.c

@@ -73,6 +73,7 @@ int h_outbound_msgbuf;
 int h_rehash;
 int h_priv_change;
 int h_cap_change;
+int h_client_tag_accept;
 
 void
 init_hook(void)
@@ -99,6 +100,7 @@ init_hook(void)
 	h_rehash = register_hook("rehash");
 	h_priv_change = register_hook("priv_change");
 	h_cap_change = register_hook("cap_change");
+	h_client_tag_accept = register_hook("client_tag_accept");
 }
 
 /* grow_hooktable()

ircd/msgbuf.c

@@ -133,6 +133,14 @@ msgbuf_parse(struct MsgBuf *msgbuf, char *line)
 			return 1;
 		}
 	}
+
+	msgbuf_partial_parse(msgbuf, ch);
+}
+
+int
+msgbuf_partial_parse(struct MsgBuf *msgbuf, char *line)
+{
+	char *ch = line;
 
 	/* truncate message if it's too long */
 	if (strlen(ch) > DATALEN) {

ircd/send.c

@@ -266,11 +266,14 @@ linebuf_put_msgf(buf_head_t *linebuf, const rb_strf_t *message, const char *form
  * notes        - to make this reentrant, find a solution for `buf` below
  */
 static void
-build_msgbuf_tags(struct MsgBuf *msgbuf, struct Client *from)
+build_msgbuf_tags(struct MsgBuf *msgbuf, struct Client *from, char* buf)
 {
 	hook_data hdata;
 
 	msgbuf_init(msgbuf);
+	if (buf != NULL) {
+		msgbuf_partial_parse(msgbuf, buf);
+	}
 
 	hdata.client = from;
 	hdata.arg1 = msgbuf;
@@ -301,7 +304,7 @@ sendto_one(struct Client *target_p, const char *pattern, ...)
 
 	rb_linebuf_newbuf(&linebuf);
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 	va_start(args, pattern);
 	linebuf_put_tags(&linebuf, &msgbuf, target_p, &strings);
 	va_end(args);
@@ -335,8 +338,8 @@ sendto_one_prefix(struct Client *target_p, struct Client *source_p,
 		sendto_realops_snomask(SNO_GENERAL, L_ALL, "Trying to send to myself!");
 		return;
 	}
-
-	build_msgbuf_tags(&msgbuf, source_p);
+	
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 	rb_linebuf_newbuf(&linebuf);
 	va_start(args, pattern);
@@ -374,7 +377,7 @@ sendto_one_notice(struct Client *target_p, const char *pattern, ...)
 		return;
 	}
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 
 	rb_linebuf_newbuf(&linebuf);
 	va_start(args, pattern);
@@ -413,7 +416,7 @@ sendto_one_numeric(struct Client *target_p, int numeric, const char *pattern, ..
 		return;
 	}
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 
 	rb_linebuf_newbuf(&linebuf);
 	va_start(args, pattern);
@@ -513,12 +516,13 @@ sendto_channel_flags(struct Client *one, int type, struct Client *source_p,
 
 	current_serial++;
 
-	build_msgbuf_tags(&msgbuf, source_p);
-
 	va_start(args, pattern);
 	vsnprintf(buf, sizeof buf, pattern, args);
 	va_end(args);
 
+	build_msgbuf_tags(&msgbuf, source_p, buf);
+
+	// TODO: linebuf_put_msgf should not exist.
 	linebuf_put_msgf(&rb_linebuf_remote, NULL, ":%s %s", use_id(source_p), buf);
 	msgbuf_cache_initf(&msgbuf_cache, &msgbuf, &strings,
 		IsPerson(source_p) ? ":%1$s!%2$s@%3$s " : ":%1$s ",
@@ -597,7 +601,7 @@ sendto_channel_opmod(struct Client *one, struct Client *source_p,
 	rb_linebuf_newbuf(&rb_linebuf_old);
 	rb_linebuf_newbuf(&rb_linebuf_new);
 
-	build_msgbuf_tags(&msgbuf, source_p);
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 	current_serial++;
 	const char *statusmsg_prefix = (ConfigChannel.opmod_send_statusmsg ? "@" : "");
@@ -694,7 +698,7 @@ _sendto_channel_local(struct Client *source_p, int type, const char *priv, struc
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, source_p);
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
 
@@ -765,7 +769,7 @@ _sendto_channel_local_with_capability_butone(struct Client *source_p, struct Cli
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, source_p);
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
 
 	RB_DLINK_FOREACH_SAFE(ptr, next_ptr, chptr->locmembers.head)
@@ -844,7 +848,7 @@ sendto_channel_local_butone(struct Client *one, int type, struct Channel *chptr,
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, one);
+	build_msgbuf_tags(&msgbuf, one, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
@@ -899,7 +903,7 @@ sendto_common_channels_local(struct Client *user, int cap, int negcap, const cha
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, user);
+	build_msgbuf_tags(&msgbuf, user, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
@@ -966,7 +970,7 @@ sendto_common_channels_local_butone(struct Client *user, int cap, int negcap, co
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, user);
+	build_msgbuf_tags(&msgbuf, user, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
@@ -1022,12 +1026,12 @@ sendto_match_butone(struct Client *one, struct Client *source_p,
 
 	rb_linebuf_newbuf(&rb_linebuf_remote);
 
-	build_msgbuf_tags(&msgbuf, source_p);
-
 	va_start(args, pattern);
 	vsnprintf(buf, sizeof(buf), pattern, args);
 	va_end(args);
 
+	build_msgbuf_tags(&msgbuf, source_p, buf);
+
 	msgbuf_cache_initf(&msgbuf_cache, &msgbuf, &strings,
 		IsServer(source_p) ? ":%s " : ":%s!%s@%s ",
 		source_p->name, source_p->username, source_p->host);
@@ -1145,7 +1149,7 @@ sendto_local_clients_with_capability(int cap, const char *pattern, ...)
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
@@ -1181,7 +1185,7 @@ sendto_monitor(struct Client *source_p, struct monitor *monptr, const char *patt
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, source_p);
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_init(&msgbuf_cache, &msgbuf, &strings);
@@ -1224,7 +1228,7 @@ _sendto_anywhere(struct Client *dest_p, struct Client *target_p,
 		} else {
 			struct MsgBuf msgbuf;
 
-			build_msgbuf_tags(&msgbuf, source_p);
+			build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 			linebuf_put_tagsf(&linebuf, &msgbuf, dest_p, &strings,
 				IsPerson(source_p) ? ":%1$s!%4$s@%5$s %2$s %3$s " : ":%1$s %2$s %3$s ",
@@ -1299,13 +1303,13 @@ sendto_realops_snomask(int flags, int level, const char *pattern, ...)
 	struct MsgBuf msgbuf;
 	struct MsgBuf_cache msgbuf_cache;
 
-	build_msgbuf_tags(&msgbuf, &me);
-
 	/* rather a lot of copying around, oh well -- jilles */
 	va_start(args, pattern);
 	vsnprintf(buf, sizeof(buf), pattern, args);
 	va_end(args);
 
+	build_msgbuf_tags(&msgbuf, &me, buf);
+
 	msgbuf_cache_initf(&msgbuf_cache, &msgbuf, NULL,
 		":%s NOTICE * :*** Notice -- %s", me.name, buf);
 
@@ -1361,7 +1365,7 @@ sendto_realops_snomask_from(int flags, int level, struct Client *source_p,
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 
 	va_start(args, pattern);
 	msgbuf_cache_initf(&msgbuf_cache, &msgbuf, &strings,
@@ -1407,7 +1411,7 @@ sendto_wallops_flags(int flags, struct Client *source_p, const char *pattern, ..
 	struct MsgBuf_cache msgbuf_cache;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, source_p);
+	build_msgbuf_tags(&msgbuf, source_p, NULL);
 
 	va_start(args, pattern);
 	if (IsPerson(source_p)) {
@@ -1446,7 +1450,7 @@ kill_client(struct Client *target_p, struct Client *diedie, const char *pattern,
 	struct MsgBuf msgbuf;
 	rb_strf_t strings = { .format = pattern, .format_args = &args, .next = NULL };
 
-	build_msgbuf_tags(&msgbuf, &me);
+	build_msgbuf_tags(&msgbuf, &me, NULL);
 
 	rb_linebuf_newbuf(&linebuf);
 

ircd/supported.c

@@ -79,6 +79,7 @@
 #include "supported.h"
 #include "chmode.h"
 #include "send.h"
+#include "client_tags.h"
 
 static char allowed_chantypes[BUFSIZE];
 rb_dlink_list isupportlist;
@@ -304,9 +305,14 @@ static const char *
 isupport_client_tag_deny(const void *ptr)
 {
 	static char result[200];
-	// TODO: iterate over allowed client tags declared by modules
-	// add -x, -y, -z for each of them.
-	snprintf(result, sizeof result, "%s", "*");
+	static char exceptions[198];
+
+	format_client_tags(exceptions, sizeof exceptions, "-%s", ",");
+
+	if (EmptyString(exceptions))
+		snprintf(result, sizeof result, "%s", "*");
+	else
+		snprintf(result, sizeof result, "%s,%s", "*", exceptions);
 	return result;
 }
 

modules/Makefile.am

@@ -8,6 +8,7 @@ LIBS += $(top_srcdir)/ircd/libircd.la
 auto_load_moddir=@moduledir@/autoload
 
 auto_load_mod_LTLIBRARIES = \
+	cap_message_tags.la \
   cap_account_tag.la \
   cap_server_time.la \
   chm_nocolour.la \