diff options
Diffstat (limited to 'src/libmime')
| -rw-r--r-- | src/libmime/mime_encoding.c | 66 |
1 files changed, 60 insertions, 6 deletions
diff --git a/src/libmime/mime_encoding.c b/src/libmime/mime_encoding.c index 04027552e..990eda62e 100644 --- a/src/libmime/mime_encoding.c +++ b/src/libmime/mime_encoding.c @@ -622,6 +622,61 @@ rspamd_mime_charset_find_by_content (const gchar *in, gsize inlen, return NULL; } +static const char * +rspamd_mime_charset_find_by_content_maybe_split (const gchar *in, gsize inlen) +{ + if (inlen < RSPAMD_CHARSET_MAX_CONTENT * 3) { + return rspamd_mime_charset_find_by_content (in, inlen, false); + } + else { + const gchar *c1, *c2, *c3; + + c1 = rspamd_mime_charset_find_by_content (in, RSPAMD_CHARSET_MAX_CONTENT, false); + c2 = rspamd_mime_charset_find_by_content (in + inlen / 2, + RSPAMD_CHARSET_MAX_CONTENT, false); + c3 = rspamd_mime_charset_find_by_content (in + inlen - RSPAMD_CHARSET_MAX_CONTENT, + RSPAMD_CHARSET_MAX_CONTENT, false); + + /* 7bit stuff */ + if (strcmp (c1, "US-ASCII") == 0) { + c1 = NULL; /* Invalid - we have 8 bit there */ + } + if (strcmp (c2, "US-ASCII") == 0) { + c2 = NULL; /* Invalid - we have 8 bit there */ + } + if (strcmp (c3, "US-ASCII") == 0) { + c2 = NULL; /* Invalid - we have 8 bit there */ + } + + if (!c1) { + c1 = c2 ? c2 : c3; + } + if (!c2) { + c2 = c3 ? c3 : c1; + } + if (!c3) { + c3 = c1 ? c2 : c1; + } + + if (c1 && c2 && c3) { + /* Quorum */ + if (c1 == c2) { + return c1; + } + else if (c2 == c3) { + return c2; + } + else if (c1 == c3) { + return c3; + } + + /* All charsets are distinct */ + } + + return NULL; + } +} + gboolean rspamd_mime_charset_utf_check (rspamd_ftok_t *charset, gchar *in, gsize len, gboolean content_check) @@ -643,8 +698,7 @@ rspamd_mime_charset_utf_check (rspamd_ftok_t *charset, */ if (content_check) { if (rspamd_fast_utf8_validate (in, len) != 0) { - real_charset = rspamd_mime_charset_find_by_content (in, - MIN (RSPAMD_CHARSET_MAX_CONTENT, len), FALSE); + real_charset = rspamd_mime_charset_find_by_content_maybe_split(in, len); if (real_charset) { @@ -715,8 +769,8 @@ rspamd_mime_text_part_maybe_convert (struct rspamd_task *task, if (part->ct->charset.len == 0) { if (need_charset_heuristic) { - charset = rspamd_mime_charset_find_by_content (part_content->data, - MIN (RSPAMD_CHARSET_MAX_CONTENT, part_content->len), FALSE); + charset = rspamd_mime_charset_find_by_content_maybe_split (text_part->parsed.begin, + text_part->parsed.len); if (charset != NULL) { msg_info_task ("detected charset %s", charset); @@ -740,8 +794,8 @@ rspamd_mime_text_part_maybe_convert (struct rspamd_task *task, if (charset == NULL) { /* We don't know the real charset but can try heuristic */ if (need_charset_heuristic) { - charset = rspamd_mime_charset_find_by_content (part_content->data, - MIN (RSPAMD_CHARSET_MAX_CONTENT, part_content->len), FALSE); + charset = rspamd_mime_charset_find_by_content_maybe_split (part_content->data, + part_content->len); msg_info_task ("detected charset: %s", charset); checked = TRUE; text_part->real_charset = charset; |