commit 9e7bf60: [Rework] Change the way to extract URLs when dealing with alternative parts

[Vsevolod Stakhov]

Author: Vsevolod Stakhov
Date: 2020-03-19 16:06:42 +0000
URL: https://github.com/rspamd/rspamd/commit/9e7bf606f92f56911d6f31a9b8b1e7d030ca27a7 (HEAD -> master)

[Rework] Change the way to extract URLs when dealing with alternative parts

---
 src/libmime/message.c | 45 +++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 41 insertions(+), 4 deletions(-)

diff --git a/src/libmime/message.c b/src/libmime/message.c
index c45550e6d..f167730d4 100644
--- a/src/libmime/message.c
+++ b/src/libmime/message.c
@@ -859,12 +859,49 @@ rspamd_message_process_text_part_maybe (struct rspamd_task *task,
 	rspamd_normalize_text_part (task, text_part);
 
 	if (!IS_PART_HTML (text_part)) {
-		rspamd_url_text_extract (task->task_pool, task, text_part,
-				RSPAMD_URL_FIND_ALL);
+		if (mime_part->parent_part) {
+			struct rspamd_mime_part *parent = mime_part->parent_part;
+
+			if (IS_PART_MULTIPART (parent) && parent->specific.mp->children->len == 2) {
+				/*
+				 * Use strict extraction mode: we will extract missing urls from
+				 * an html part if needed
+				 */
+				rspamd_url_text_extract (task->task_pool, task, text_part,
+						RSPAMD_URL_FIND_STRICT);
+			}
+			else {
+				/*
+				 * Fall back to full text extraction using TLD patterns
+				 */
+				rspamd_url_text_extract (task->task_pool, task, text_part,
+						RSPAMD_URL_FIND_ALL);
+			}
+		}
+		else {
+			/*
+			 * Fall back to full text extraction using TLD patterns
+			*/
+			rspamd_url_text_extract (task->task_pool, task, text_part,
+					RSPAMD_URL_FIND_ALL);
+		}
 	}
 	else {
-		rspamd_url_text_extract (task->task_pool, task, text_part,
-				RSPAMD_URL_FIND_STRICT);
+		if (mime_part->parent_part) {
+			struct rspamd_mime_part *parent = mime_part->parent_part;
+
+			if (IS_PART_MULTIPART (parent) && parent->specific.mp->children->len == 2) {
+				/* Do not extract urls from HTML at all */
+			}
+			else {
+				rspamd_url_text_extract (task->task_pool, task, text_part,
+						RSPAMD_URL_FIND_STRICT);
+			}
+		}
+		else {
+			rspamd_url_text_extract (task->task_pool, task, text_part,
+					RSPAMD_URL_FIND_STRICT);
+		}
 	}
 
 	if (text_part->exceptions) {