urlapi: simplify junkscan

Makes it smaller and possibly somewhat faster

Closes #16307

diff --git a/lib/urlapi.c b/lib/urlapi.c
index 2368bd79b588aec3732a6232df231440c57ecf79..c93c9722eb5eec8f3eb7e074979fedc0df1e5cea 100644 (file)
--- a/lib/urlapi.c
+++ b/lib/urlapi.c
@@ -332,27 +332,20 @@ static CURLUcode redirect_url(char *base, const char *relurl,
 }
 
 /* scan for byte values <= 31, 127 and sometimes space */
-static CURLUcode junkscan(const char *url, size_t *urllen, unsigned int flags)
+static CURLUcode junkscan(const char *url, size_t *urllen, bool allowspace)
 {
-  static const char badbytes[]={
-    /* */ 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
-    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
-    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
-    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
-    0x7f, 0x00 /* null-terminate */
-  };
   size_t n = strlen(url);
-  size_t nfine;
-
+  size_t i;
+  unsigned char control;
+  const unsigned char *p = (const unsigned char *)url;
   if(n > CURL_MAX_INPUT_LENGTH)
-    /* excessive input length */
-    return CURLUE_MALFORMED_INPUT;
-
-  nfine = strcspn(url, badbytes);
-  if((nfine != n) ||
-     (!(flags & CURLU_ALLOW_SPACE) && strchr(url, ' ')))
     return CURLUE_MALFORMED_INPUT;
 
+  control = allowspace ? 0x1f : 0x20;
+  for(i = 0; i < n; i++) {
+    if(p[i] <= control || p[i] == 127)
+      return CURLUE_MALFORMED_INPUT;
+  }
   *urllen = n;
   return CURLUE_OK;
 }
@@ -946,7 +939,7 @@ static CURLUcode parseurl(const char *url, CURLU *u, unsigned int flags)
 
   Curl_dyn_init(&host, CURL_MAX_INPUT_LENGTH);
 
-  result = junkscan(url, &urllen, flags);
+  result = junkscan(url, &urllen, !!(flags & CURLU_ALLOW_SPACE));
   if(result)
     goto fail;