cssp: Fix handling of nonce

diff --git a/libfreerdp/core/nla.c b/libfreerdp/core/nla.c
index 018c0df..2c0f141 100644 (file)
--- a/libfreerdp/core/nla.c
+++ b/libfreerdp/core/nla.c
@@ -1124,22 +1124,12 @@ SECURITY_STATUS nla_encrypt_public_key_hash(rdpNla* nla)
        const BYTE* hashMagic = nla->server ? ServerClientHashMagic : ClientServerHashMagic;
        const size_t hashSize = nla->server ? sizeof(ServerClientHashMagic) : sizeof(ClientServerHashMagic);
 
-       if (!sspi_SecBufferAlloc(&nla->ClientNonce, NonceLength))
-       {
-               status = SEC_E_INSUFFICIENT_MEMORY;
-               goto out;
-       }
-
        if (!sspi_SecBufferAlloc(&nla->pubKeyAuth, auth_data_length))
        {
                status = SEC_E_INSUFFICIENT_MEMORY;
                goto out;
        }
 
-       /* generate random 32-byte nonce */
-       if (winpr_RAND(nla->ClientNonce.pvBuffer, NonceLength) < 0)
-               goto out;
-
        /* generate SHA256 of following data: ClientServerHashMagic, Nonce, SubjectPublicKey */
        if (!(sha256 = winpr_Digest_New()))
                goto out;
@@ -2258,23 +2248,27 @@ rdpNla* nla_new(freerdp* instance, rdpTransport* transport, rdpSettings* setting
        nla->recvSeqNum = 0;
        nla->version = 6;
 
+       ZeroMemory(&nla->ClientNonce, sizeof(SecBuffer));
+       ZeroMemory(&nla->negoToken, sizeof(SecBuffer));
+       ZeroMemory(&nla->pubKeyAuth, sizeof(SecBuffer));
+       ZeroMemory(&nla->authInfo, sizeof(SecBuffer));
+       SecInvalidateHandle(&nla->context);
+
        if (settings->NtlmSamFile)
        {
                nla->SamFile = _strdup(settings->NtlmSamFile);
 
                if (!nla->SamFile)
-               {
-                       free(nla->identity);
-                       free(nla);
-                       return NULL;
-               }
+                       goto cleanup;
        }
 
-       ZeroMemory(&nla->negoToken, sizeof(SecBuffer));
-       ZeroMemory(&nla->pubKeyAuth, sizeof(SecBuffer));
-       ZeroMemory(&nla->authInfo, sizeof(SecBuffer));
-       ZeroMemory(&nla->ClientNonce, sizeof(SecBuffer));
-       SecInvalidateHandle(&nla->context);
+       /* init to 0 or we end up freeing a bad pointer if the alloc fails */
+       if (!sspi_SecBufferAlloc(&nla->ClientNonce, NonceLength))
+               goto cleanup;
+
+       /* generate random 32-byte nonce */
+       if (winpr_RAND(nla->ClientNonce.pvBuffer, NonceLength) < 0)
+               goto cleanup;
 
        if (nla->server)
        {
@@ -2301,8 +2295,7 @@ rdpNla* nla_new(freerdp* instance, rdpTransport* transport, rdpSettings* setting
                if (!nla->SspiModule)
                {
                        RegCloseKey(hKey);
-                       free(nla);
-                       return NULL;
+                       goto cleanup;
                }
 
                status = RegQueryValueEx(hKey, _T("SspiModule"), NULL, &dwType,
@@ -2315,6 +2308,10 @@ rdpNla* nla_new(freerdp* instance, rdpTransport* transport, rdpSettings* setting
        }
 
        return nla;
+
+cleanup:
+       nla_free(nla);
+       return NULL;
 }
 
 /**