[Feature] Process font size in HTML parser

diff --git a/src/libserver/html.c b/src/libserver/html.c
index 1ee012388d442a90cba31cc30d2bb9c2078ddeb9..a7ddf09628d7c818b6eb028c10761fb1c3967fa3 100644 (file)
--- a/src/libserver/html.c
+++ b/src/libserver/html.c
@@ -1147,6 +1147,29 @@ rspamd_html_parse_tag_component (rspamd_mempool_t *pool,
                        NEW_COMPONENT (RSPAMD_HTML_COMPONENT_STYLE);
                }
        }
+       else if (tag->id == Tag_FONT) {
+               if (len == 5){
+                       if (g_ascii_strncasecmp (p, "color", len) == 0) {
+                               NEW_COMPONENT (RSPAMD_HTML_COMPONENT_COLOR);
+                       }
+                       else if (g_ascii_strncasecmp (p, "style", len) == 0) {
+                               NEW_COMPONENT (RSPAMD_HTML_COMPONENT_STYLE);
+                       }
+                       else if (g_ascii_strncasecmp (p, "class", len) == 0) {
+                               NEW_COMPONENT (RSPAMD_HTML_COMPONENT_CLASS);
+                       }
+               }
+               else if (len == 7) {
+                       if (g_ascii_strncasecmp (p, "bgcolor", len) == 0) {
+                               NEW_COMPONENT (RSPAMD_HTML_COMPONENT_BGCOLOR);
+                       }
+               }
+               else if (len == 4) {
+                       if (g_ascii_strncasecmp (p, "size", len) == 0) {
+                               NEW_COMPONENT (RSPAMD_HTML_COMPONENT_SIZE);
+                       }
+               }
+       }
        else if (tag->flags & FL_BLOCK) {
                if (len == 5){
                        if (g_ascii_strncasecmp (p, "color", len) == 0) {
@@ -1940,6 +1963,114 @@ rspamd_html_process_color (const gchar *line, guint len, struct html_color *cl)
        }
 }
 
+static void
+rspamd_html_process_font_size (const gchar *line, guint len, guint *fs,
+                                                          gboolean is_css)
+{
+       const gchar *p = line, *end = line + len;
+       gchar *err = NULL, numbuf[64];
+       guint numlen = 0;
+       gdouble sz = 0;
+
+       while (p < end && g_ascii_isspace (*p)) {
+               p ++;
+               len --;
+       }
+
+       numlen = rspamd_memspn (p, "0123456789.-", len);
+
+       rspamd_strlcpy (numbuf, p, MIN (sizeof (numbuf), numlen + 1));
+       sz = strtod (numbuf, &err);
+
+       /* Now check leftover */
+       if (sz < 0) {
+               sz = 0;
+       }
+
+       if (err && *err != '\0') {
+               const gchar *e = err;
+
+               /* Skip spaces */
+               while (*e && g_ascii_isspace (*e)) {
+                       e ++;
+               }
+
+               /* Lowercase */
+               rspamd_str_lc ((gchar *)e, strlen (e));
+
+               if (memcmp (e, "px", 2) == 0) {
+                       sz = (guint)sz; /* Round to number */
+               }
+               else if (memcmp (e, "em", 2) == 0) {
+                       /* EM is 16 px, so multiply and round */
+                       sz = (guint)(sz * 16.0);
+               }
+               else if (*e == '%') {
+                       /* Percentages from 16 px */
+                       sz = (guint)(sz / 100.0 * 16.0);
+               }
+
+               else if (memcmp (e, "vw", 2) == 0) {
+                       /*
+                        * Vewport width in percentages:
+                        * we assume 1% of viewport width as 8px
+                        */
+                       sz = (guint)(sz * 8.0);
+               }
+               else if (memcmp (e, "vh", 2) == 0) {
+                       /*
+                        * Vewport height in percentages
+                        * we assume 1% of viewport width as 6px
+                        */
+                       sz = (guint)(sz * 6.0);
+               }
+               else {
+                       /* Failsafe - garbadge */
+                       if (is_css) {
+                               /*
+                                * In css mode we usually ignore sizes, but let's treat
+                                * small sizes specially
+                                */
+                               if (sz < 1) {
+                                       sz = 0;
+                               }
+                               else {
+                                       sz = 1; /* Ignore */
+                               }
+                       }
+                       else {
+                               /* In non-css mode we have to check legacy size */
+                               sz = sz * 16;
+                       }
+               }
+       }
+       else {
+               /* Failsafe naked number */
+               if (is_css) {
+                       /*
+                        * In css mode we usually ignore sizes, but let's treat
+                        * small sizes specially
+                        */
+                       if (sz < 1) {
+                               sz = 0;
+                       }
+                       else {
+                               sz = 1; /* Ignore */
+                       }
+               }
+               else {
+                       /* In non-css mode we have to check legacy size */
+                       sz = sz * 16;
+               }
+       }
+
+       if (sz > 32) {
+               sz = 32;
+       }
+
+       *fs = sz;
+}
+
 static void
 rspamd_html_process_style (rspamd_mempool_t *pool, struct html_block *bl,
                struct html_content *hc, const gchar *style, guint len)
@@ -2009,6 +2140,16 @@ rspamd_html_process_style (rspamd_mempool_t *pool, struct html_block *bl,
                                                        msg_debug_html ("tag is not visible");
                                                }
                                        }
+                                       else if (klen == 9 && g_ascii_strncasecmp (key, "font-size", 9) == 0) {
+                                               rspamd_html_process_font_size (c, p - c,
+                                                               &bl->font_size, TRUE);
+                                               msg_debug_html ("got font size: %u", bl->font_size);
+
+                                               if (bl->font_size < 3) {
+                                                       bl->visible = FALSE;
+                                                       msg_debug_html ("tag is not visible");
+                                               }
+                                       }
                                }
 
                                key = NULL;
@@ -2049,39 +2190,58 @@ rspamd_html_process_block_tag (rspamd_mempool_t *pool, struct html_tag *tag,
        bl = rspamd_mempool_alloc0 (pool, sizeof (*bl));
        bl->tag = tag;
        bl->visible = TRUE;
+       bl->font_size = (guint)-1;
 
        while (cur) {
                comp = cur->data;
 
-               if (comp->type == RSPAMD_HTML_COMPONENT_COLOR && comp->len > 0) {
-                       fstr.begin = (gchar *)comp->start;
-                       fstr.len = comp->len;
-                       rspamd_html_process_color (comp->start, comp->len, &bl->font_color);
-                       msg_debug_html ("got color: %xd", bl->font_color.d.val);
-               }
-               else if (comp->type == RSPAMD_HTML_COMPONENT_BGCOLOR && comp->len > 0) {
-                       fstr.begin = (gchar *)comp->start;
-                       fstr.len = comp->len;
-                       rspamd_html_process_color (comp->start, comp->len, &bl->background_color);
-                       msg_debug_html ("got color: %xd", bl->font_color.d.val);
-
-                       if (tag->id == Tag_BODY) {
-                               /* Set global background color */
-                               memcpy (&hc->bgcolor, &bl->background_color, sizeof (hc->bgcolor));
+               if (comp->len > 0) {
+                       switch (comp->type) {
+                       case RSPAMD_HTML_COMPONENT_COLOR:
+                               fstr.begin = (gchar *) comp->start;
+                               fstr.len = comp->len;
+                               rspamd_html_process_color (comp->start, comp->len,
+                                               &bl->font_color);
+                               msg_debug_html ("got color: %xd", bl->font_color.d.val);
+                               break;
+                       case RSPAMD_HTML_COMPONENT_BGCOLOR:
+                               fstr.begin = (gchar *) comp->start;
+                               fstr.len = comp->len;
+                               rspamd_html_process_color (comp->start, comp->len,
+                                               &bl->background_color);
+                               msg_debug_html ("got color: %xd", bl->font_color.d.val);
+
+                               if (tag->id == Tag_BODY) {
+                                       /* Set global background color */
+                                       memcpy (&hc->bgcolor, &bl->background_color,
+                                                       sizeof (hc->bgcolor));
+                               }
+                               break;
+                       case RSPAMD_HTML_COMPONENT_STYLE:
+                               bl->style.len = comp->len;
+                               bl->style.start = comp->start;
+                               msg_debug_html ("got style: %*s", (gint) bl->style.len,
+                                               bl->style.start);
+                               rspamd_html_process_style (pool, bl, hc, comp->start, comp->len);
+                               break;
+                       case RSPAMD_HTML_COMPONENT_CLASS:
+                               fstr.begin = (gchar *) comp->start;
+                               fstr.len = comp->len;
+                               bl->class = rspamd_mempool_ftokdup (pool, &fstr);
+                               msg_debug_html ("got class: %s", bl->class);
+                               break;
+                       case RSPAMD_HTML_COMPONENT_SIZE:
+                               fstr.begin = (gchar *) comp->start;
+                               fstr.len = comp->len;
+                               rspamd_html_process_color (comp->start, comp->len,
+                                               &bl->font_color);
+                               msg_debug_html ("got color: %xd", bl->font_color.d.val);
+                               break;
+                       default:
+                               /* NYI */
+                               break;
                        }
                }
-               else if (comp->type == RSPAMD_HTML_COMPONENT_STYLE && comp->len > 0) {
-                       bl->style.len = comp->len;
-                       bl->style.start =  comp->start;
-                       msg_debug_html ("got style: %*s", (gint)bl->style.len, bl->style.start);
-                       rspamd_html_process_style (pool, bl, hc, comp->start, comp->len);
-               }
-               else if (comp->type == RSPAMD_HTML_COMPONENT_CLASS && comp->len > 0) {
-                       fstr.begin = (gchar *)comp->start;
-                       fstr.len = comp->len;
-                       bl->class = rspamd_mempool_ftokdup (pool, &fstr);
-                       msg_debug_html ("got class: %s", bl->class);
-               }
 
                cur = g_list_next (cur);
        }
@@ -2102,6 +2262,7 @@ rspamd_html_process_block_tag (rspamd_mempool_t *pool, struct html_tag *tag,
                        }
                }
        }
+
        if (!bl->font_color.valid) {
                /* Try to propagate background color from parent nodes */
                for (parent = tag->parent; parent != NULL; parent = parent->parent) {
@@ -2119,6 +2280,22 @@ rspamd_html_process_block_tag (rspamd_mempool_t *pool, struct html_tag *tag,
                }
        }
 
+       /* Propagate font size */
+       if (bl->font_size == (guint)-1) {
+               for (parent = tag->parent; parent != NULL; parent = parent->parent) {
+                       parent_tag = parent->data;
+
+                       if (parent_tag && (parent_tag->flags & FL_BLOCK) && parent_tag->extra) {
+                               bl_parent = parent_tag->extra;
+
+                               if (bl_parent->font_size != (guint)-1) {
+                                       bl->font_size = bl_parent->font_size;
+                                       break;
+                               }
+                       }
+               }
+       }
+
        /* Set bgcolor to the html bgcolor and font color to black as a last resort */
        if (!bl->font_color.valid) {
                bl->font_color.d.val = 0;
@@ -2128,6 +2305,9 @@ rspamd_html_process_block_tag (rspamd_mempool_t *pool, struct html_tag *tag,
        if (!bl->background_color.valid) {
                memcpy (&bl->background_color, &hc->bgcolor, sizeof (hc->bgcolor));
        }
+       if (bl->font_size == (guint)-1) {
+               bl->font_size = 16; /* Default for browsers */
+       }
 
        if (hc->blocks == NULL) {
                hc->blocks = g_ptr_array_sized_new (64);

diff --git a/src/libserver/html.h b/src/libserver/html.h
index 84d5e2bc2e2c51828c33cfeb60648a7fe8c05064..44a14a0f7d449f0b9edaa941916af5f96f258d5d 100644 (file)
--- a/src/libserver/html.h
+++ b/src/libserver/html.h
@@ -33,7 +33,8 @@ enum html_component_type {
        RSPAMD_HTML_COMPONENT_STYLE,
        RSPAMD_HTML_COMPONENT_CLASS,
        RSPAMD_HTML_COMPONENT_WIDTH,
-       RSPAMD_HTML_COMPONENT_HEIGHT
+       RSPAMD_HTML_COMPONENT_HEIGHT,
+       RSPAMD_HTML_COMPONENT_SIZE
 };
 
 struct html_tag_component {