http_negotiate_sspi: Use a dynamic buffer for SPN generation

Updated to use a dynamic buffer for the SPN generation via the recently
introduced Curl_sasl_build_spn() function rather than a fixed buffer of
1024 characters, which should have been more than enough, but by using
the new function removes the need for another variable sname to do the
wide character conversion in Unicode builds.

1 files changed, 10 insertions, 16 deletions

diff --git a/lib/http_negotiate_sspi.c b/lib/http_negotiate_sspi.c
index a745e9dc2..a986b164b 100644
--- a/lib/http_negotiate_sspi.c
+++ b/lib/http_negotiate_sspi.c
@@ -31,6 +31,7 @@
 #include "rawstr.h"
 #include "warnless.h"
 #include "curl_base64.h"
+#include "curl_sasl.h"
 #include "http_negotiate.h"
 #include "curl_memory.h"
 #include "curl_multibyte.h"
@@ -46,19 +47,16 @@ get_gss_name(struct connectdata *conn, bool proxy,
              struct negotiatedata *neg_ctx)
 {
   const char* service = "HTTP";
-  size_t length;
 
   if(proxy && !conn->proxy.name)
     /* proxy auth requested but no given proxy name, error out! */
     return -1;
 
-  length = strlen(service) + 1 + strlen(proxy ? conn->proxy.name :
-                                        conn->host.name) + 1;
-  if(length + 1 > sizeof(neg_ctx->server_name))
-    return EMSGSIZE;
-
-  snprintf(neg_ctx->server_name, sizeof(neg_ctx->server_name), "%s/%s",
-           service, proxy ? conn->proxy.name : conn->host.name);
+  neg_ctx->server_name = Curl_sasl_build_spn(service,
+                                             proxy ? conn->proxy.name :
+                                                     conn->host.name);
+  if(!neg_ctx->server_name)
+    return -1;
 
   return 0;
 }
@@ -75,7 +73,6 @@ int Curl_input_negotiate(struct connectdata *conn, bool proxy,
   SecBuffer         in_sec_buff;
   unsigned long     context_attributes;
   TimeStamp         lifetime;
-  TCHAR             *sname;
   int ret;
   size_t len = 0, input_token_len = 0;
   CURLcode error;
@@ -113,7 +110,7 @@ int Curl_input_negotiate(struct connectdata *conn, bool proxy,
     return -1;
   }
 
-  if(!strlen(neg_ctx->server_name)) {
+  if(!neg_ctx->server_name) {
     ret = get_gss_name(conn, proxy, neg_ctx);
     if(ret)
       return ret;
@@ -203,15 +200,11 @@ int Curl_input_negotiate(struct connectdata *conn, bool proxy,
     in_sec_buff.cbBuffer   = curlx_uztoul(input_token_len);
   }
 
-  sname = Curl_convert_UTF8_to_tchar(neg_ctx->server_name);
-  if(!sname)
-    return CURLE_OUT_OF_MEMORY;
-
   /* Generate our message */
   neg_ctx->status = s_pSecFn->InitializeSecurityContext(
     neg_ctx->credentials,
     input_token ? neg_ctx->context : NULL,
-    sname,
+    neg_ctx->server_name,
     ISC_REQ_CONFIDENTIALITY,
     0,
     SECURITY_NATIVE_DREP,
@@ -222,7 +215,6 @@ int Curl_input_negotiate(struct connectdata *conn, bool proxy,
     &context_attributes,
     &lifetime);
 
-  Curl_unicodefree(sname);
   Curl_safefree(input_token);
 
   if(GSS_ERROR(neg_ctx->status))
@@ -293,6 +285,8 @@ static void cleanup(struct negotiatedata *neg_ctx)
   neg_ctx->max_token_length = 0;
   Curl_safefree(neg_ctx->output_token);
 
+  Curl_safefree(neg_ctx->server_name);
+
   Curl_sspi_free_identity(neg_ctx->p_identity);
   neg_ctx->p_identity = NULL;
 }