add keyword hook, work in progress

4 files changed, 187 insertions, 13 deletions

diff --git a/Makefile b/Makefile
index 6496448..70b9900 100644
--- a/Makefile
+++ b/Makefile
@@ -16,6 +16,7 @@ CFLAGS += -I$(DOVECOT)/src/lib-storage/
 CFLAGS += -I$(DOVECOT)/src/lib-mail/
 CFLAGS += -I$(DOVECOT)/src/lib-imap/
 CFLAGS += -I$(DOVECOT)/src/lib-dict/
+CFLAGS += -I$(DOVECOT)/src/lib-index/
 CFLAGS += -I$(DOVECOT)/src/imap/
 
 # output name
diff --git a/antispam-plugin.c b/antispam-plugin.c
index 407b909..5dd9a02 100644
--- a/antispam-plugin.c
+++ b/antispam-plugin.c
@@ -49,6 +49,11 @@ static char *default_spam_folders[] = {
 static char **spam_folders = default_spam_folders;
 static char **unsure_folders = NULL;
 bool antispam_can_append_to_spam = FALSE;
+static char **spam_keywords = NULL;
+
+bool need_keyword_hook;
+bool need_folder_hook;
+
 
 static bool mailbox_in_list(struct mailbox *box, char **list)
 {
@@ -79,6 +84,22 @@ bool mailbox_is_unsure(struct mailbox *box)
 	return mailbox_in_list(box, unsure_folders);
 }
 
+bool keyword_is_spam(const char *keyword)
+{
+	char **k = spam_keywords;
+
+	if (!spam_keywords)
+		return FALSE;
+
+	while (*k) {
+		if (strcmp(*k, keyword) == 0)
+			return TRUE;
+		k++;
+	}
+
+	return FALSE;
+}
+
 const char *get_setting(const char *name)
 {
 	const char *env;
@@ -105,6 +126,7 @@ void PLUGIN_FUNCTION(init)(void)
 {
 	const char *tmp;
 	char * const *iter;
+	int spam_folder_count = 0;
 
 	debug("plugin initialising\n");
 
@@ -127,17 +149,12 @@ void PLUGIN_FUNCTION(init)(void)
 	if (tmp)
 		spam_folders = p_strsplit(global_pool, tmp, ";");
 
-	tmp = get_setting("ALLOW_APPEND_TO_SPAM");
-	if (tmp && strcasecmp(tmp, "yes") == 0) {
-		antispam_can_append_to_spam = TRUE;
-		debug("allowing APPEND to spam folders");
-	}
-
 	if (spam_folders) {
 		iter = spam_folders;
 		while (*iter) {
 			debug("\"%s\" is spam folder\n", *iter);
 			iter++;
+			spam_folder_count++;
 		}
 	} else
 		debug("no spam folders\n");
@@ -155,6 +172,28 @@ void PLUGIN_FUNCTION(init)(void)
 	} else
 		debug("no unsure folders\n");
 
+	tmp = get_setting("ALLOW_APPEND_TO_SPAM");
+	if (tmp && strcasecmp(tmp, "yes") == 0) {
+		antispam_can_append_to_spam = TRUE;
+		debug("allowing APPEND to spam folders");
+	}
+
+	tmp = get_setting("SPAM_KEYWORDS");
+	if (tmp)
+		spam_keywords = p_strsplit(global_pool, tmp, ";");
+
+	if (spam_keywords) {
+		iter = spam_keywords;
+		while (*iter) {
+			debug("\"%s\" is spam keyword\n", *iter);
+			iter++;
+		}
+	}
+
+	/* set spam_folders to empty to only allow keywords */
+	need_folder_hook = !!spam_folder_count;
+	need_keyword_hook = !!spam_keywords;
+
 	backend_init(global_pool);
 
 	antispam_next_hook_mail_storage_created = hook_mail_storage_created;
diff --git a/antispam-plugin.h b/antispam-plugin.h
index 98fed8f..9869a14 100644
--- a/antispam-plugin.h
+++ b/antispam-plugin.h
@@ -51,5 +51,9 @@ bool mailbox_is_trash(struct mailbox *box);
 bool mailbox_is_unsure(struct mailbox *box);
 const char *get_setting(const char *name);
 bool antispam_can_append_to_spam;
+bool keyword_is_spam(const char *keyword);
+
+extern bool need_keyword_hook;
+extern bool need_folder_hook;
         
 #endif /* _ANTISPAM_PLUGIN_H */
diff --git a/antispam-storage-1.0.c b/antispam-storage-1.0.c
index e1b00fa..1949454 100644
--- a/antispam-storage-1.0.c
+++ b/antispam-storage-1.0.c
@@ -12,6 +12,7 @@
 #include "array.h"
 #include "istream.h"
 #include "mail-search.h"
+#include "mail-index.h"
 #include "mail-storage-private.h"
 
 #include "antispam-plugin.h"
@@ -53,6 +54,10 @@ struct antispam_mailbox {
 	unsigned int save_hack:1;
 };
 
+struct antispam_mail {
+	struct mail_vfuncs super;
+};
+
 static unsigned int antispam_storage_module_id = 0;
 static bool antispam_storage_module_id_set = FALSE;
 
@@ -257,6 +262,98 @@ antispam_transaction_commit(struct mailbox_transaction_context *ctx,
 	return ret;
 }
 
+static int
+antispam_mail_update_keywords(struct mail *mail,
+			      enum modify_type modify_type,
+			      struct mail_keywords *keywords)
+{
+	struct mail_private *pmail = (struct mail_private *)mail;
+	struct antispam_mail *amail = ANTISPAM_CONTEXT(pmail);
+	int ret;
+	unsigned int i, numkwds;
+	const array_t *idxkwd = mail_index_get_keywords(keywords->index);
+	const char *const *keyword_names = array_get(idxkwd, &numkwds);
+	const char *const *orig_keywords;
+	bool previous_spam_keyword, now_spam_keyword;
+
+	switch (modify_type) {
+	case MODIFY_ADD:
+		debug("adding keyword(s)\n");
+		break;
+	case MODIFY_REMOVE:
+		debug("removing keyword(s)\n");
+		break;
+	case MODIFY_REPLACE:
+		debug("replacing keyword(s)\n");
+		break;
+	default:
+		i_assert(0);
+	}
+
+	orig_keywords = pmail->v.get_keywords(mail);
+	if (orig_keywords) {
+		debug("original keyword list:\n");
+		while (*orig_keywords) {
+			debug(" * %s\n", *orig_keywords);
+			if (keyword_is_spam(*orig_keywords))
+				previous_spam_keyword = TRUE;
+			orig_keywords++;
+		}
+	}
+
+	debug("keyword list:\n");
+
+	for (i = 0; i < keywords->count; i++) {
+		unsigned int idx = keywords->idx[i];
+
+		i_assert(idx < numkwds);
+
+		debug(" * %s\n", keyword_names[idx]);
+
+		switch (modify_type) {
+		case MODIFY_ADD:
+		case MODIFY_REPLACE:
+			if (keyword_is_spam(keyword_names[idx]))
+				now_spam_keyword = TRUE;
+			break;
+		case MODIFY_REMOVE:
+			if (keyword_is_spam(keyword_names[idx]))
+				now_spam_keyword = FALSE;
+			break;
+		default:
+			i_assert(0);
+		}
+	}
+
+	ret = amail->super.update_keywords(mail, modify_type, keywords);
+
+	debug("ret = %d\n", ret);
+
+	debug("previous-spam, now-spam: %d, %d\n",
+	      previous_spam_keyword, now_spam_keyword);
+
+	if (previous_spam_keyword != now_spam_keyword) {
+		/*
+		 * Call backend here.
+		 *
+		 * TODO: It is not clear how to roll back the
+		 *       keyword change if the backend fails.
+		 */
+	}
+
+	return ret;
+}
+
+static void
+antispam_mail_free(struct mail *mail)
+{
+	struct mail_private *pmail = (struct mail_private *)mail;
+	struct antispam_mail *amail = ANTISPAM_CONTEXT(pmail);
+
+	amail->super.free(mail);
+	i_free(amail);
+}
+
 static struct mailbox_transaction_context *
 antispam_mailbox_transaction_begin(struct mailbox *box,
 				   enum mailbox_transaction_flags flags)
@@ -296,6 +393,33 @@ antispam_mailbox_transaction_rollback(struct mailbox_transaction_context *ctx)
 	asbox->super.transaction_rollback(ctx);
 }
 
+static struct mail *
+antispam_mailbox_mail_alloc(struct mailbox_transaction_context *ctx,
+			    enum mail_fetch_field wanted_fields,
+			    struct mailbox_header_lookup_ctx *wanted_headers)
+{
+	struct antispam_mailbox *asbox = ANTISPAM_CONTEXT(ctx->box);
+	struct antispam_mail *amail = i_new(struct antispam_mail, 1);
+	struct mail_private *pmail;
+
+	/* XXX: is this cast the right thing to do? */
+	pmail = (struct mail_private *) asbox->super.mail_alloc(
+						ctx,
+						wanted_fields,
+						wanted_headers);
+
+	amail->super = pmail->v;
+
+	array_idx_set(&pmail->module_contexts,
+		      antispam_storage_module_id,
+		      &amail);
+
+	pmail->v.update_keywords = antispam_mail_update_keywords;
+	pmail->v.free = antispam_mail_free;
+
+	return (struct mail *)pmail;
+}
+
 static struct mailbox *antispam_mailbox_open(struct mail_storage *storage,
 					     const char *name,
 					     struct istream *input,
@@ -314,13 +438,19 @@ static struct mailbox *antispam_mailbox_open(struct mail_storage *storage,
 	asbox->save_hack = FALSE;
 	asbox->movetype = MMT_APPEND;
 
-	/* override save_init to override want_mail, we need that */
-	box->v.save_init = antispam_save_init;
-	box->v.save_finish = antispam_save_finish;
-	box->v.transaction_begin = antispam_mailbox_transaction_begin;
-	box->v.transaction_commit = antispam_mailbox_transaction_commit;
-	box->v.transaction_rollback = antispam_mailbox_transaction_rollback;
-	box->v.copy = antispam_copy;
+	if (need_folder_hook) {
+		/* override save_init to override want_mail, we need that */
+		box->v.save_init = antispam_save_init;
+		box->v.save_finish = antispam_save_finish;
+		box->v.transaction_begin = antispam_mailbox_transaction_begin;
+		box->v.transaction_commit = antispam_mailbox_transaction_commit;
+		box->v.transaction_rollback = antispam_mailbox_transaction_rollback;
+		box->v.copy = antispam_copy;
+	}
+
+	if (need_keyword_hook)
+		box->v.mail_alloc = antispam_mailbox_mail_alloc;
+
 	array_idx_set(&box->module_contexts, antispam_storage_module_id,
 		      &asbox);
 	return box;