FreeRDP/libfreerdp/core/credssp_auth.c
akallabeth 4033698266 [core,credssp] Add additional checks
* Better state checks
* Improved log messages
* Assertions for debug builds
2022-12-02 15:08:09 +01:00

1065 lines
28 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
*
*
* Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
* Copyright 2022 David Fort <contact@hardening-consulting.com>
* Copyright 2022 Isaac Klein <fifthdegree@protonmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <ctype.h>
#include <freerdp/config.h>
#include <freerdp/build-config.h>
#include <freerdp/settings.h>
#include <freerdp/peer.h>
#include <winpr/crt.h>
#include <winpr/assert.h>
#include <winpr/library.h>
#include <winpr/registry.h>
#include <freerdp/log.h>
#include "credssp_auth.h"
#define TAG FREERDP_TAG("core.auth")
#define SERVER_KEY "Software\\" FREERDP_VENDOR_STRING "\\" FREERDP_PRODUCT_STRING "\\Server"
enum AUTH_STATE
{
AUTH_STATE_INITIAL,
AUTH_STATE_CREDS,
AUTH_STATE_IN_PROGRESS,
AUTH_STATE_FINAL
};
struct rdp_credssp_auth
{
const rdpContext* rdp_ctx;
SecurityFunctionTable* table;
SecPkgInfo* info;
SEC_WINNT_AUTH_IDENTITY identity;
SEC_WINPR_NTLM_SETTINGS ntlmSettings;
SEC_WINPR_KERBEROS_SETTINGS kerberosSettings;
CredHandle credentials;
BOOL server;
SecPkgContext_Bindings* bindings;
TCHAR* spn;
WCHAR* package_list;
CtxtHandle context;
SecBuffer input_buffer;
SecBuffer output_buffer;
ULONG flags;
SecPkgContext_Sizes sizes;
enum AUTH_STATE state;
#ifdef UNICODE
char* pkgNameA;
#endif
};
static const char* credssp_auth_state_string(const rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth);
switch (auth->state)
{
case AUTH_STATE_INITIAL:
return "AUTH_STATE_INITIAL";
case AUTH_STATE_CREDS:
return "AUTH_STATE_CREDS";
case AUTH_STATE_IN_PROGRESS:
return "AUTH_STATE_IN_PROGRESS";
case AUTH_STATE_FINAL:
return "AUTH_STATE_FINAL";
default:
return "AUTH_STATE_UNKNOWN";
}
}
static BOOL parseKerberosDeltat(const char* value, INT32* dest, const char* message);
static BOOL credssp_auth_setup_identity(rdpCredsspAuth* auth);
static SecurityFunctionTable* auth_resolve_sspi_table(const rdpSettings* settings);
rdpCredsspAuth* credssp_auth_new(const rdpContext* rdp_ctx)
{
rdpCredsspAuth* auth = calloc(1, sizeof(rdpCredsspAuth));
if (auth)
auth->rdp_ctx = rdp_ctx;
return auth;
}
BOOL credssp_auth_init(rdpCredsspAuth* auth, TCHAR* pkg_name, SecPkgContext_Bindings* bindings)
{
SECURITY_STATUS status;
WINPR_ASSERT(auth);
WINPR_ASSERT(auth->rdp_ctx);
const rdpSettings* settings = auth->rdp_ctx->settings;
WINPR_ASSERT(settings);
auth->table = auth_resolve_sspi_table(settings);
if (!auth->table)
{
WLog_ERR(TAG, "Unable to initialize sspi table");
return FALSE;
}
/* Package name will be stored in the info structure */
WINPR_ASSERT(auth->table->QuerySecurityPackageInfo);
status = auth->table->QuerySecurityPackageInfo(pkg_name, &auth->info);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "QuerySecurityPackageInfo (%s) failed with %s [0x%08X]", pkg_name,
GetSecurityStatusString(status), status);
return FALSE;
}
WLog_DBG(TAG, "Using package: %s (cbMaxToken: %u bytes)", pkg_name, auth->info->cbMaxToken);
/* Setup common identity settings */
if (!credssp_auth_setup_identity(auth))
return FALSE;
auth->bindings = bindings;
return TRUE;
}
static BOOL credssp_auth_setup_auth_data(rdpCredsspAuth* auth,
const SEC_WINNT_AUTH_IDENTITY* identity,
SEC_WINNT_AUTH_IDENTITY_WINPR* pAuthData)
{
SEC_WINNT_AUTH_IDENTITY_EXW* identityEx;
WINPR_ASSERT(pAuthData);
ZeroMemory(pAuthData, sizeof(SEC_WINNT_AUTH_IDENTITY_WINPR));
identityEx = &pAuthData->identity;
identityEx->Version = SEC_WINNT_AUTH_IDENTITY_VERSION;
identityEx->Length = sizeof(SEC_WINNT_AUTH_IDENTITY_EX);
identityEx->User = identity->User;
identityEx->UserLength = identity->UserLength;
identityEx->Domain = identity->Domain;
identityEx->DomainLength = identity->DomainLength;
identityEx->Password = identity->Password;
identityEx->PasswordLength = identity->PasswordLength;
identityEx->Flags = identity->Flags;
identityEx->Flags |= SEC_WINNT_AUTH_IDENTITY_UNICODE;
identityEx->Flags |= SEC_WINNT_AUTH_IDENTITY_EXTENDED;
if (auth->package_list)
{
identityEx->PackageList = (UINT16*)auth->package_list;
identityEx->PackageListLength = _wcslen(auth->package_list);
}
pAuthData->ntlmSettings = &auth->ntlmSettings;
pAuthData->kerberosSettings = &auth->kerberosSettings;
return TRUE;
}
static BOOL credssp_auth_client_init_cred_attributes(rdpCredsspAuth* auth)
{
SECURITY_STATUS status;
WINPR_ASSERT(auth);
if (auth->kerberosSettings.kdcUrl)
{
#ifdef UNICODE
SecPkgCredentials_KdcUrlW secAttr = { NULL };
secAttr.KdcUrl = ConvertUtf8ToWCharAlloc(auth->kerberosSettings.kdcUrl, NULL);
if (!secAttr.KdcUrl)
return FALSE;
if (auth->table->SetCredentialsAttributesW)
status = auth->table->SetCredentialsAttributesW(
&auth->credentials, SECPKG_CRED_ATTR_KDC_URL, (void*)&secAttr, sizeof(secAttr));
else
status = SEC_E_UNSUPPORTED_FUNCTION;
free(secAttr.KdcUrl);
#else
SecPkgCredentials_KdcUrlA secAttr = { NULL };
secAttr.KdcUrl = auth->kerberosSettings.kdcUrl;
if (auth->table->SetCredentialsAttributesA)
status = auth->table->SetCredentialsAttributesA(
&auth->credentials, SECPKG_CRED_ATTR_KDC_URL, (void*)&secAttr, sizeof(secAttr));
else
status = SEC_E_UNSUPPORTED_FUNCTION;
#endif
if (status != SEC_E_OK)
{
WLog_WARN(TAG, "Explicit Kerberos KDC URL (%s) injection is not supported",
auth->kerberosSettings.kdcUrl);
}
}
return TRUE;
}
BOOL credssp_auth_setup_client(rdpCredsspAuth* auth, const char* target_service,
const char* target_hostname, const SEC_WINNT_AUTH_IDENTITY* identity,
const char* pkinit)
{
SECURITY_STATUS status;
void* pAuthData = NULL;
SEC_WINNT_AUTH_IDENTITY_WINPR winprAuthData;
WINPR_ASSERT(auth);
WINPR_ASSERT(auth->table);
WINPR_ASSERT(auth->info);
WINPR_ASSERT(auth->state == AUTH_STATE_INITIAL);
/* Construct the service principal name */
if (!credssp_auth_set_spn(auth, target_service, target_hostname))
return FALSE;
if (identity)
{
credssp_auth_setup_auth_data(auth, identity, &winprAuthData);
if (pkinit)
{
auth->kerberosSettings.pkinitX509Identity = _strdup(pkinit);
if (!auth->kerberosSettings.pkinitX509Identity)
{
WLog_ERR(TAG, "unable to copy pkinitArgs");
return FALSE;
}
}
pAuthData = (void*)&winprAuthData;
}
WINPR_ASSERT(auth->table->AcquireCredentialsHandle);
status =
auth->table->AcquireCredentialsHandle(NULL, auth->info->Name, SECPKG_CRED_OUTBOUND, NULL,
pAuthData, NULL, NULL, &auth->credentials, NULL);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "AcquireCredentialsHandleA failed with %s [0x%08X]",
GetSecurityStatusString(status), status);
return FALSE;
}
if (!credssp_auth_client_init_cred_attributes(auth))
{
WLog_ERR(TAG, "Fatal error setting credential attributes");
return FALSE;
}
auth->state = AUTH_STATE_CREDS;
WLog_DBG(TAG, "Acquired client credentials");
return TRUE;
}
BOOL credssp_auth_setup_server(rdpCredsspAuth* auth)
{
SECURITY_STATUS status;
void* pAuthData = NULL;
SEC_WINNT_AUTH_IDENTITY_WINPR winprAuthData;
WINPR_ASSERT(auth);
WINPR_ASSERT(auth->table);
WINPR_ASSERT(auth->state == AUTH_STATE_INITIAL);
if (auth->ntlmSettings.samFile || auth->ntlmSettings.hashCallback ||
auth->kerberosSettings.keytab)
{
credssp_auth_setup_auth_data(auth, &auth->identity, &winprAuthData);
pAuthData = &winprAuthData;
}
WINPR_ASSERT(auth->table->AcquireCredentialsHandle);
status =
auth->table->AcquireCredentialsHandle(NULL, auth->info->Name, SECPKG_CRED_INBOUND, NULL,
pAuthData, NULL, NULL, &auth->credentials, NULL);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "AcquireCredentialsHandleA failed with %s [0x%08X]",
GetSecurityStatusString(status), status);
return FALSE;
}
auth->state = AUTH_STATE_CREDS;
WLog_DBG(TAG, "Acquired server credentials");
auth->server = TRUE;
return TRUE;
}
void credssp_auth_set_flags(rdpCredsspAuth* auth, ULONG flags)
{
WINPR_ASSERT(auth);
auth->flags = flags;
}
/**
* SSPI Client Ceremony
*
* --------------
* ( Client Begin )
* --------------
* |
* |
* \|/
* -----------+--------------
* | AcquireCredentialsHandle |
* --------------------------
* |
* |
* \|/
* -------------+--------------
* +---------------> / InitializeSecurityContext /
* | ----------------------------
* | |
* | |
* | \|/
* --------------------------- ---------+------------- ----------------------
* / Receive blob from server / < Received security blob? > --Yes-> / Send blob to server /
* -------------+------------- ----------------------- ----------------------
* /|\ | |
* | No |
* Yes \|/ |
* | ------------+----------- |
* +---------------- < Received Continue Needed > <-----------------+
* ------------------------
* |
* No
* \|/
* ------+-------
* ( Client End )
* --------------
*/
int credssp_auth_authenticate(rdpCredsspAuth* auth)
{
SECURITY_STATUS status;
SecBuffer input_buffers[2] = { 0 };
SecBufferDesc input_buffer_desc = { SECBUFFER_VERSION, 1, input_buffers };
CtxtHandle* context = NULL;
WINPR_ASSERT(auth);
WINPR_ASSERT(auth->table);
SecBufferDesc output_buffer_desc = { SECBUFFER_VERSION, 1, &auth->output_buffer };
switch (auth->state)
{
case AUTH_STATE_CREDS:
case AUTH_STATE_IN_PROGRESS:
break;
case AUTH_STATE_INITIAL:
case AUTH_STATE_FINAL:
WLog_ERR(TAG, "%s: context in invalid state!", __FUNCTION__);
return -1;
}
/* input buffer will be null on first call,
* context MUST be NULL on first call */
context = &auth->context;
if (!auth->context.dwLower && !auth->context.dwUpper)
context = NULL;
input_buffers[0] = auth->input_buffer;
if (auth->bindings)
{
input_buffer_desc.cBuffers = 2;
input_buffers[1].BufferType = SECBUFFER_CHANNEL_BINDINGS;
input_buffers[1].cbBuffer = auth->bindings->BindingsLength;
input_buffers[1].pvBuffer = auth->bindings->Bindings;
}
/* Free previous output buffer (presumably no longer needed) */
sspi_SecBufferFree(&auth->output_buffer);
auth->output_buffer.BufferType = SECBUFFER_TOKEN;
if (!sspi_SecBufferAlloc(&auth->output_buffer, auth->info->cbMaxToken))
return -1;
if (auth->server)
{
WINPR_ASSERT(auth->table->AcceptSecurityContext);
status = auth->table->AcceptSecurityContext(
&auth->credentials, context, &input_buffer_desc, auth->flags, SECURITY_NATIVE_DREP,
&auth->context, &output_buffer_desc, &auth->flags, NULL);
}
else
{
WINPR_ASSERT(auth->table->InitializeSecurityContext);
status = auth->table->InitializeSecurityContext(
&auth->credentials, context, auth->spn, auth->flags, 0, SECURITY_NATIVE_DREP,
&input_buffer_desc, 0, &auth->context, &output_buffer_desc, &auth->flags, NULL);
}
if (status == SEC_E_OK)
{
WLog_DBG(TAG, "Authentication complete (output token size: %lu bytes)",
auth->output_buffer.cbBuffer);
auth->state = AUTH_STATE_FINAL;
/* Not terrible if this fails, although encryption functions may run into issues down the
* line, still, authentication succeeded */
WINPR_ASSERT(auth->table->QueryContextAttributes);
status =
auth->table->QueryContextAttributes(&auth->context, SECPKG_ATTR_SIZES, &auth->sizes);
WLog_DBG(TAG, "Context sizes: cbMaxSignature=%d, cbSecurityTrailer=%d",
auth->sizes.cbMaxSignature, auth->sizes.cbSecurityTrailer);
return 1;
}
else if (status == SEC_I_CONTINUE_NEEDED)
{
WLog_DBG(TAG, "Authentication in progress... (output token size: %lu)",
auth->output_buffer.cbBuffer);
auth->state = AUTH_STATE_IN_PROGRESS;
return 0;
}
else
{
WLog_ERR(TAG, "%s failed with %s [0x%08X]",
auth->server ? "AcceptSecurityContext" : "InitializeSecurityContext",
GetSecurityStatusString(status), status);
return -1;
}
}
/* Plaintext is not modified; Output buffer MUST be freed if encryption succeeds */
BOOL credssp_auth_encrypt(rdpCredsspAuth* auth, const SecBuffer* plaintext, SecBuffer* ciphertext,
size_t* signature_length, ULONG sequence)
{
SECURITY_STATUS status;
SecBuffer buffers[2];
SecBufferDesc buffer_desc = { SECBUFFER_VERSION, 2, buffers };
BYTE* buf = NULL;
WINPR_ASSERT(auth && auth->table);
WINPR_ASSERT(plaintext);
WINPR_ASSERT(ciphertext);
switch (auth->state)
{
case AUTH_STATE_INITIAL:
WLog_ERR(TAG, "[%s] Invalid state %s", __FUNCTION__, credssp_auth_state_string(auth));
return FALSE;
default:
break;
}
/* Allocate consecutive memory for ciphertext and signature */
buf = calloc(1, plaintext->cbBuffer + auth->sizes.cbSecurityTrailer);
if (!buf)
return FALSE;
buffers[0].BufferType = SECBUFFER_TOKEN;
buffers[0].cbBuffer = auth->sizes.cbSecurityTrailer;
buffers[0].pvBuffer = buf;
buffers[1].BufferType = SECBUFFER_DATA;
buffers[1].pvBuffer = buf + auth->sizes.cbSecurityTrailer;
buffers[1].cbBuffer = plaintext->cbBuffer;
CopyMemory(buffers[1].pvBuffer, plaintext->pvBuffer, plaintext->cbBuffer);
WINPR_ASSERT(auth->table->EncryptMessage);
status = auth->table->EncryptMessage(&auth->context, 0, &buffer_desc, sequence);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "EncryptMessage failed with %s [0x%08X]", GetSecurityStatusString(status),
status);
free(buf);
return FALSE;
}
if (buffers[0].cbBuffer < auth->sizes.cbSecurityTrailer)
{
/* The signature is smaller than cbSecurityTrailer, so shrink the excess in between */
MoveMemory(((BYTE*)buffers[0].pvBuffer) + buffers[0].cbBuffer, buffers[1].pvBuffer,
buffers[1].cbBuffer);
// use reported signature size as new cbSecurityTrailer value for DecryptMessage
auth->sizes.cbSecurityTrailer = buffers[0].cbBuffer;
}
ciphertext->cbBuffer = buffers[0].cbBuffer + buffers[1].cbBuffer;
ciphertext->pvBuffer = buf;
if (signature_length)
*signature_length = buffers[0].cbBuffer;
return TRUE;
}
/* Output buffer MUST be freed if decryption succeeds */
BOOL credssp_auth_decrypt(rdpCredsspAuth* auth, const SecBuffer* ciphertext, SecBuffer* plaintext,
ULONG sequence)
{
SECURITY_STATUS status;
SecBuffer buffers[2];
SecBufferDesc buffer_desc = { SECBUFFER_VERSION, 2, buffers };
ULONG fqop;
WINPR_ASSERT(auth && auth->table);
WINPR_ASSERT(ciphertext);
WINPR_ASSERT(plaintext);
switch (auth->state)
{
case AUTH_STATE_INITIAL:
WLog_ERR(TAG, "[%s] Invalid state %s", __FUNCTION__, credssp_auth_state_string(auth));
return FALSE;
default:
break;
}
/* Sanity check: ciphertext must at least have a signature */
if (ciphertext->cbBuffer < auth->sizes.cbSecurityTrailer)
{
WLog_ERR(TAG, "Encrypted message buffer too small");
return FALSE;
}
/* Split the input into signature and encrypted data; we assume the signature length is equal to
* cbSecurityTrailer */
buffers[0].BufferType = SECBUFFER_TOKEN;
buffers[0].pvBuffer = ciphertext->pvBuffer;
buffers[0].cbBuffer = auth->sizes.cbSecurityTrailer;
buffers[1].BufferType = SECBUFFER_DATA;
if (!sspi_SecBufferAlloc(&buffers[1], ciphertext->cbBuffer - auth->sizes.cbSecurityTrailer))
return FALSE;
CopyMemory(buffers[1].pvBuffer, (BYTE*)ciphertext->pvBuffer + auth->sizes.cbSecurityTrailer,
buffers[1].cbBuffer);
WINPR_ASSERT(auth->table->DecryptMessage);
status = auth->table->DecryptMessage(&auth->context, &buffer_desc, sequence, &fqop);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "DecryptMessage failed with %s [0x%08X]", GetSecurityStatusString(status),
status);
sspi_SecBufferFree(&buffers[1]);
return FALSE;
}
*plaintext = buffers[1];
return TRUE;
}
BOOL credssp_auth_impersonate(rdpCredsspAuth* auth)
{
SECURITY_STATUS status;
WINPR_ASSERT(auth && auth->table);
WINPR_ASSERT(auth->table->ImpersonateSecurityContext);
status = auth->table->ImpersonateSecurityContext(&auth->context);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "ImpersonateSecurityContext failed with %s [0x%08X]",
GetSecurityStatusString(status), status);
return FALSE;
}
return TRUE;
}
BOOL credssp_auth_revert_to_self(rdpCredsspAuth* auth)
{
SECURITY_STATUS status;
WINPR_ASSERT(auth && auth->table);
WINPR_ASSERT(auth->table->RevertSecurityContext);
status = auth->table->RevertSecurityContext(&auth->context);
if (status != SEC_E_OK)
{
WLog_ERR(TAG, "RevertSecurityContext failed with %s [0x%08X]",
GetSecurityStatusString(status), status);
return FALSE;
}
return TRUE;
}
void credssp_auth_take_input_buffer(rdpCredsspAuth* auth, SecBuffer* buffer)
{
WINPR_ASSERT(auth);
WINPR_ASSERT(buffer);
sspi_SecBufferFree(&auth->input_buffer);
auth->input_buffer = *buffer;
auth->input_buffer.BufferType = SECBUFFER_TOKEN;
/* Invalidate original, rdpCredsspAuth now has ownership of the buffer */
SecBuffer empty = { 0 };
*buffer = empty;
}
const SecBuffer* credssp_auth_get_output_buffer(rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth);
return &auth->output_buffer;
}
BOOL credssp_auth_have_output_token(rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth);
return auth->output_buffer.cbBuffer ? TRUE : FALSE;
}
BOOL credssp_auth_is_complete(rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth);
return auth->state == AUTH_STATE_FINAL;
}
size_t credssp_auth_trailer_size(rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth);
return auth->sizes.cbSecurityTrailer;
}
const char* credssp_auth_pkg_name(rdpCredsspAuth* auth)
{
WINPR_ASSERT(auth && auth->info);
#ifdef UNICODE
if (!auth->pkgNameA)
{
WINPR_ASSERT(auth->info->Name);
auth->pkgNameA = ConvertUtf8ToWCharAlloc(auth->info->Name, NULL);
}
return auth->pkgNameA;
#else
return auth->info->Name;
#endif
}
void credssp_auth_free(rdpCredsspAuth* auth)
{
SEC_WINPR_KERBEROS_SETTINGS* krb_settings;
SEC_WINPR_NTLM_SETTINGS* ntlm_settings;
if (!auth)
return;
if (auth->table)
{
switch (auth->state)
{
case AUTH_STATE_IN_PROGRESS:
case AUTH_STATE_FINAL:
WINPR_ASSERT(auth->table->DeleteSecurityContext);
auth->table->DeleteSecurityContext(&auth->context);
/* FALLTHROUGH */
case AUTH_STATE_CREDS:
WINPR_ASSERT(auth->table->FreeCredentialsHandle);
auth->table->FreeCredentialsHandle(&auth->credentials);
break;
case AUTH_STATE_INITIAL:
default:
break;
}
if (auth->info)
{
WINPR_ASSERT(auth->table->FreeContextBuffer);
auth->table->FreeContextBuffer(auth->info);
}
}
sspi_FreeAuthIdentity(&auth->identity);
krb_settings = &auth->kerberosSettings;
ntlm_settings = &auth->ntlmSettings;
free(krb_settings->kdcUrl);
free(krb_settings->cache);
free(krb_settings->keytab);
free(krb_settings->armorCache);
free(krb_settings->pkinitX509Anchors);
free(krb_settings->pkinitX509Identity);
free(ntlm_settings->samFile);
free(auth->package_list);
free(auth->spn);
sspi_SecBufferFree(&auth->input_buffer);
sspi_SecBufferFree(&auth->output_buffer);
#ifdef UNICODE
free(auth->pkgNameA);
#endif
free(auth);
}
static void auth_get_sspi_module_from_reg(char** sspi_module)
{
HKEY hKey;
DWORD dwType, dwSize;
WINPR_ASSERT(sspi_module);
*sspi_module = NULL;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, SERVER_KEY, 0, KEY_READ | KEY_WOW64_64KEY, &hKey) !=
ERROR_SUCCESS)
return;
if (RegQueryValueExA(hKey, "SspiModule", NULL, &dwType, NULL, &dwSize) != ERROR_SUCCESS)
{
RegCloseKey(hKey);
return;
}
*sspi_module = (LPSTR)malloc(dwSize + sizeof(CHAR));
if (!(*sspi_module))
{
RegCloseKey(hKey);
return;
}
if (RegQueryValueExA(hKey, "SspiModule", NULL, &dwType, (BYTE*)(*sspi_module), &dwSize) !=
ERROR_SUCCESS)
{
RegCloseKey(hKey);
free(*sspi_module);
return;
}
RegCloseKey(hKey);
}
static SecurityFunctionTable* auth_resolve_sspi_table(const rdpSettings* settings)
{
char* sspi_module = NULL;
WINPR_ASSERT(settings);
if (settings->ServerMode)
auth_get_sspi_module_from_reg(&sspi_module);
if (sspi_module || settings->SspiModule)
{
INIT_SECURITY_INTERFACE InitSecurityInterface_ptr;
const char* module_name = sspi_module ? sspi_module : settings->SspiModule;
#ifdef UNICODE
const char* proc_name = "InitSecurityInterfaceW";
#else
const char* proc_name = "InitSecurityInterfaceA";
#endif /* UNICODE */
HMODULE hSSPI = LoadLibraryX(module_name);
if (!hSSPI)
{
WLog_ERR(TAG, "Failed to load SSPI module: %s", module_name);
return FALSE;
}
WLog_INFO(TAG, "Using SSPI Module: %s", module_name);
InitSecurityInterface_ptr = (INIT_SECURITY_INTERFACE)GetProcAddress(hSSPI, proc_name);
free(sspi_module);
return InitSecurityInterface_ptr();
}
return InitSecurityInterfaceEx(0);
}
static BOOL credssp_auth_setup_identity(rdpCredsspAuth* auth)
{
const rdpSettings* settings;
SEC_WINPR_KERBEROS_SETTINGS* krb_settings;
SEC_WINPR_NTLM_SETTINGS* ntlm_settings;
freerdp_peer* peer;
WINPR_ASSERT(auth);
WINPR_ASSERT(auth->rdp_ctx);
peer = auth->rdp_ctx->peer;
settings = auth->rdp_ctx->settings;
WINPR_ASSERT(settings);
krb_settings = &auth->kerberosSettings;
ntlm_settings = &auth->ntlmSettings;
if (settings->KerberosLifeTime)
parseKerberosDeltat(settings->KerberosLifeTime, &krb_settings->lifeTime, "lifetime");
if (settings->KerberosStartTime)
parseKerberosDeltat(settings->KerberosStartTime, &krb_settings->startTime, "starttime");
if (settings->KerberosRenewableLifeTime)
parseKerberosDeltat(settings->KerberosRenewableLifeTime, &krb_settings->renewLifeTime,
"renewLifeTime");
if (settings->KerberosKdcUrl)
{
krb_settings->kdcUrl = _strdup(settings->KerberosKdcUrl);
if (!krb_settings->kdcUrl)
{
WLog_ERR(TAG, "unable to copy kdcUrl");
return FALSE;
}
}
if (settings->KerberosCache)
{
krb_settings->cache = _strdup(settings->KerberosCache);
if (!krb_settings->cache)
{
WLog_ERR(TAG, "unable to copy cache name");
return FALSE;
}
}
if (settings->KerberosKeytab)
{
krb_settings->keytab = _strdup(settings->KerberosKeytab);
if (!krb_settings->keytab)
{
WLog_ERR(TAG, "unable to copy keytab name");
return FALSE;
}
}
if (settings->KerberosArmor)
{
krb_settings->armorCache = _strdup(settings->KerberosArmor);
if (!krb_settings->armorCache)
{
WLog_ERR(TAG, "unable to copy armorCache");
return FALSE;
}
}
if (settings->PkinitAnchors)
{
krb_settings->pkinitX509Anchors = _strdup(settings->PkinitAnchors);
if (!krb_settings->pkinitX509Anchors)
{
WLog_ERR(TAG, "unable to copy pkinitX509Anchors");
return FALSE;
}
}
if (settings->NtlmSamFile)
{
ntlm_settings->samFile = _strdup(settings->NtlmSamFile);
if (!ntlm_settings->samFile)
{
WLog_ERR(TAG, "unable to copy samFile");
return FALSE;
}
}
if (peer && peer->SspiNtlmHashCallback)
{
ntlm_settings->hashCallback = peer->SspiNtlmHashCallback;
ntlm_settings->hashCallbackArg = peer;
}
if (settings->AuthenticationPackageList)
{
auth->package_list = ConvertUtf8ToWCharAlloc(settings->AuthenticationPackageList, NULL);
if (!auth->package_list)
return FALSE;
}
auth->identity.Flags |= SEC_WINNT_AUTH_IDENTITY_UNICODE;
auth->identity.Flags |= SEC_WINNT_AUTH_IDENTITY_EXTENDED;
return TRUE;
}
BOOL credssp_auth_set_spn(rdpCredsspAuth* auth, const char* service, const char* hostname)
{
size_t length;
char* spn;
WINPR_ASSERT(auth);
if (!hostname)
return FALSE;
if (!service)
spn = _strdup(hostname);
else
{
length = strlen(service) + strlen(hostname) + 2;
spn = calloc(length + 1, sizeof(char));
if (!spn)
return FALSE;
sprintf_s(spn, length, "%s/%s", service, hostname);
}
if (!spn)
return FALSE;
#if defined(UNICODE)
auth->spn = ConvertUtf8ToWCharAlloc(spn, NULL);
free(spn);
#else
auth->spn = spn;
#endif
return TRUE;
}
static const char* parseInt(const char* v, INT32* r)
{
*r = 0;
/* check that we have at least a digit */
if (!*v || !((*v >= '0') && (*v <= '9')))
return NULL;
for (; *v && (*v >= '0') && (*v <= '9'); v++)
{
*r = (*r * 10) + (*v - '0');
}
return v;
}
static BOOL parseKerberosDeltat(const char* value, INT32* dest, const char* message)
{
INT32 v;
const char* ptr;
WINPR_ASSERT(value);
WINPR_ASSERT(dest);
WINPR_ASSERT(message);
/* determine the format :
* h:m[:s] (3:00:02) deltat in hours/minutes
* <n>d<n>h<n>m<n>s 1d4h deltat in day/hours/minutes/seconds
* <n> deltat in seconds
*/
ptr = strchr(value, ':');
if (ptr)
{
/* format like h:m[:s] */
*dest = 0;
value = parseInt(value, &v);
if (!value || *value != ':')
{
WLog_ERR(TAG, "Invalid value for %s", message);
return FALSE;
}
*dest = v * 3600;
value = parseInt(value + 1, &v);
if (!value || (*value != 0 && *value != ':') || (v > 60))
{
WLog_ERR(TAG, "Invalid value for %s", message);
return FALSE;
}
*dest += v * 60;
if (*value == ':')
{
/* have optional seconds */
value = parseInt(value + 1, &v);
if (!value || (*value != 0) || (v > 60))
{
WLog_ERR(TAG, "Invalid value for %s", message);
return FALSE;
}
*dest += v;
}
return TRUE;
}
/* <n> or <n>d<n>h<n>m<n>s format */
value = parseInt(value, &v);
if (!value)
{
WLog_ERR(TAG, "Invalid value for %s", message);
return FALSE;
}
if (!*value || isspace(*value))
{
/* interpret that as a value in seconds */
*dest = v;
return TRUE;
}
*dest = 0;
do
{
INT32 factor = 0;
INT32 maxValue = 0;
switch (*value)
{
case 'd':
factor = 3600 * 24;
maxValue = 0;
break;
case 'h':
factor = 3600;
maxValue = 0;
break;
case 'm':
factor = 60;
maxValue = 60;
break;
case 's':
factor = 1;
maxValue = 60;
break;
default:
WLog_ERR(TAG, "invalid value for unit %c when parsing %s", *value, message);
return FALSE;
}
if ((maxValue > 0) && (v > maxValue))
{
WLog_ERR(TAG, "invalid value for unit %c when parsing %s", *value, message);
return FALSE;
}
*dest += (v * factor);
value++;
if (!*value)
return TRUE;
value = parseInt(value, &v);
if (!value || !*value)
{
WLog_ERR(TAG, "Invalid value for %s", message);
return FALSE;
}
} while (TRUE);
return TRUE;
}