url: accept "any length" credentials for proxy auth

They're only limited to the maximum string input restrictions, not to
256 bytes.

Added test 1178 to verify

Reported-by: Will Roberts
Fixes #5448
Closes #5449

1 files changed, 7 insertions, 17 deletions

diff --git a/lib/url.c b/lib/url.c
index 0173dc88a..9c6712c0e 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -2355,24 +2355,14 @@ static CURLcode parse_proxy(struct Curl_easy *data,
 static CURLcode parse_proxy_auth(struct Curl_easy *data,
                                  struct connectdata *conn)
 {
-  char proxyuser[MAX_CURL_USER_LENGTH]="";
-  char proxypasswd[MAX_CURL_PASSWORD_LENGTH]="";
-  CURLcode result;
-
-  if(data->set.str[STRING_PROXYUSERNAME] != NULL) {
-    strncpy(proxyuser, data->set.str[STRING_PROXYUSERNAME],
-            MAX_CURL_USER_LENGTH);
-    proxyuser[MAX_CURL_USER_LENGTH-1] = '\0';   /*To be on safe side*/
-  }
-  if(data->set.str[STRING_PROXYPASSWORD] != NULL) {
-    strncpy(proxypasswd, data->set.str[STRING_PROXYPASSWORD],
-            MAX_CURL_PASSWORD_LENGTH);
-    proxypasswd[MAX_CURL_PASSWORD_LENGTH-1] = '\0'; /*To be on safe side*/
-  }
+  char *proxyuser = data->set.str[STRING_PROXYUSERNAME];
+  char *proxypasswd = data->set.str[STRING_PROXYPASSWORD];
+  CURLcode result = CURLE_OK;
 
-  result = Curl_urldecode(data, proxyuser, 0, &conn->http_proxy.user, NULL,
-                          FALSE);
-  if(!result)
+  if(proxyuser)
+    result = Curl_urldecode(data, proxyuser, 0, &conn->http_proxy.user, NULL,
+                            FALSE);
+  if(!result && proxypasswd)
     result = Curl_urldecode(data, proxypasswd, 0, &conn->http_proxy.passwd,
                             NULL, FALSE);
   return result;