blob: 43831b706fc7a5ee313064c2e2c47e9655be400d [file] [log] [blame]
/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <time.h>
#if defined(WEBRTC_WIN)
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#define SECURITY_WIN32
#include <security.h>
#endif
#include <ctype.h> // for isspace
#include <stdio.h> // for sprintf
#include <algorithm>
#include <utility> // for pair
#include <vector>
#include "rtc_base/arraysize.h"
#include "rtc_base/checks.h"
#include "rtc_base/cryptstring.h" // for CryptString
#include "rtc_base/httpcommon.h"
#include "rtc_base/logging.h"
#include "rtc_base/messagedigest.h"
#include "rtc_base/socketaddress.h"
#include "rtc_base/strings/string_builder.h"
#include "rtc_base/stringutils.h" // for strcpyn, _stricmp
#include "rtc_base/third_party/base64/base64.h" // for Base64
#include "rtc_base/zero_memory.h" // for ExplicitZeroMemory
namespace rtc {
namespace {
#if defined(WEBRTC_WIN)
///////////////////////////////////////////////////////////////////////////////
// ConstantToLabel can be used to easily generate string names from constant
// values. This can be useful for logging descriptive names of error messages.
// Usage:
// const ConstantToLabel LIBRARY_ERRORS[] = {
// KLABEL(SOME_ERROR),
// KLABEL(SOME_OTHER_ERROR),
// ...
// LASTLABEL
// }
//
// int err = LibraryFunc();
// LOG(LS_ERROR) << "LibraryFunc returned: "
// << GetErrorName(err, LIBRARY_ERRORS);
struct ConstantToLabel {
int value;
const char* label;
};
const char* LookupLabel(int value, const ConstantToLabel entries[]) {
for (int i = 0; entries[i].label; ++i) {
if (value == entries[i].value) {
return entries[i].label;
}
}
return 0;
}
std::string GetErrorName(int err, const ConstantToLabel* err_table) {
if (err == 0)
return "No error";
if (err_table != 0) {
if (const char* value = LookupLabel(err, err_table))
return value;
}
char buffer[16];
snprintf(buffer, sizeof(buffer), "0x%08x", err);
return buffer;
}
#define KLABEL(x) \
{ x, #x }
#define LASTLABEL \
{ 0, 0 }
const ConstantToLabel SECURITY_ERRORS[] = {
KLABEL(SEC_I_COMPLETE_AND_CONTINUE),
KLABEL(SEC_I_COMPLETE_NEEDED),
KLABEL(SEC_I_CONTEXT_EXPIRED),
KLABEL(SEC_I_CONTINUE_NEEDED),
KLABEL(SEC_I_INCOMPLETE_CREDENTIALS),
KLABEL(SEC_I_RENEGOTIATE),
KLABEL(SEC_E_CERT_EXPIRED),
KLABEL(SEC_E_INCOMPLETE_MESSAGE),
KLABEL(SEC_E_INSUFFICIENT_MEMORY),
KLABEL(SEC_E_INTERNAL_ERROR),
KLABEL(SEC_E_INVALID_HANDLE),
KLABEL(SEC_E_INVALID_TOKEN),
KLABEL(SEC_E_LOGON_DENIED),
KLABEL(SEC_E_NO_AUTHENTICATING_AUTHORITY),
KLABEL(SEC_E_NO_CREDENTIALS),
KLABEL(SEC_E_NOT_OWNER),
KLABEL(SEC_E_OK),
KLABEL(SEC_E_SECPKG_NOT_FOUND),
KLABEL(SEC_E_TARGET_UNKNOWN),
KLABEL(SEC_E_UNKNOWN_CREDENTIALS),
KLABEL(SEC_E_UNSUPPORTED_FUNCTION),
KLABEL(SEC_E_UNTRUSTED_ROOT),
KLABEL(SEC_E_WRONG_PRINCIPAL),
LASTLABEL};
#undef KLABEL
#undef LASTLABEL
#endif // defined(WEBRTC_WIN)
typedef std::pair<std::string, std::string> HttpAttribute;
typedef std::vector<HttpAttribute> HttpAttributeList;
inline bool IsEndOfAttributeName(size_t pos, size_t len, const char* data) {
if (pos >= len)
return true;
if (isspace(static_cast<unsigned char>(data[pos])))
return true;
// The reason for this complexity is that some attributes may contain trailing
// equal signs (like base64 tokens in Negotiate auth headers)
if ((pos + 1 < len) && (data[pos] == '=') &&
!isspace(static_cast<unsigned char>(data[pos + 1])) &&
(data[pos + 1] != '=')) {
return true;
}
return false;
}
void HttpParseAttributes(const char* data,
size_t len,
HttpAttributeList& attributes) {
size_t pos = 0;
while (true) {
// Skip leading whitespace
while ((pos < len) && isspace(static_cast<unsigned char>(data[pos]))) {
++pos;
}
// End of attributes?
if (pos >= len)
return;
// Find end of attribute name
size_t start = pos;
while (!IsEndOfAttributeName(pos, len, data)) {
++pos;
}
HttpAttribute attribute;
attribute.first.assign(data + start, data + pos);
// Attribute has value?
if ((pos < len) && (data[pos] == '=')) {
++pos; // Skip '='
// Check if quoted value
if ((pos < len) && (data[pos] == '"')) {
while (++pos < len) {
if (data[pos] == '"') {
++pos;
break;
}
if ((data[pos] == '\\') && (pos + 1 < len))
++pos;
attribute.second.append(1, data[pos]);
}
} else {
while ((pos < len) && !isspace(static_cast<unsigned char>(data[pos])) &&
(data[pos] != ',')) {
attribute.second.append(1, data[pos++]);
}
}
}
attributes.push_back(attribute);
if ((pos < len) && (data[pos] == ','))
++pos; // Skip ','
}
}
bool HttpHasAttribute(const HttpAttributeList& attributes,
const std::string& name,
std::string* value) {
for (HttpAttributeList::const_iterator it = attributes.begin();
it != attributes.end(); ++it) {
if (it->first == name) {
if (value) {
*value = it->second;
}
return true;
}
}
return false;
}
bool HttpHasNthAttribute(HttpAttributeList& attributes,
size_t index,
std::string* name,
std::string* value) {
if (index >= attributes.size())
return false;
if (name)
*name = attributes[index].first;
if (value)
*value = attributes[index].second;
return true;
}
std::string quote(const std::string& str) {
std::string result;
result.push_back('"');
for (size_t i = 0; i < str.size(); ++i) {
if ((str[i] == '"') || (str[i] == '\\'))
result.push_back('\\');
result.push_back(str[i]);
}
result.push_back('"');
return result;
}
#if defined(WEBRTC_WIN)
struct NegotiateAuthContext : public HttpAuthContext {
CredHandle cred;
CtxtHandle ctx;
size_t steps;
bool specified_credentials;
NegotiateAuthContext(const std::string& auth, CredHandle c1, CtxtHandle c2)
: HttpAuthContext(auth),
cred(c1),
ctx(c2),
steps(0),
specified_credentials(false) {}
~NegotiateAuthContext() override {
DeleteSecurityContext(&ctx);
FreeCredentialsHandle(&cred);
}
};
#endif // WEBRTC_WIN
} // anonymous namespace
HttpAuthResult HttpAuthenticate(const char* challenge,
size_t len,
const SocketAddress& server,
const std::string& method,
const std::string& uri,
const std::string& username,
const CryptString& password,
HttpAuthContext*& context,
std::string& response,
std::string& auth_method) {
HttpAttributeList args;
HttpParseAttributes(challenge, len, args);
HttpHasNthAttribute(args, 0, &auth_method, nullptr);
if (context && (context->auth_method != auth_method))
return HAR_IGNORE;
// BASIC
if (_stricmp(auth_method.c_str(), "basic") == 0) {
if (context)
return HAR_CREDENTIALS; // Bad credentials
if (username.empty())
return HAR_CREDENTIALS; // Missing credentials
context = new HttpAuthContext(auth_method);
// TODO(bugs.webrtc.org/8905): Convert sensitive to a CryptString and also
// return response as CryptString so contents get securely deleted
// automatically.
// std::string decoded = username + ":" + password;
size_t len = username.size() + password.GetLength() + 2;
char* sensitive = new char[len];
size_t pos = strcpyn(sensitive, len, username.data(), username.size());
pos += strcpyn(sensitive + pos, len - pos, ":");
password.CopyTo(sensitive + pos, true);
response = auth_method;
response.append(" ");
// TODO: create a sensitive-source version of Base64::encode
response.append(Base64::Encode(sensitive));
ExplicitZeroMemory(sensitive, len);
delete[] sensitive;
return HAR_RESPONSE;
}
// DIGEST
if (_stricmp(auth_method.c_str(), "digest") == 0) {
if (context)
return HAR_CREDENTIALS; // Bad credentials
if (username.empty())
return HAR_CREDENTIALS; // Missing credentials
context = new HttpAuthContext(auth_method);
std::string cnonce, ncount;
char buffer[256];
sprintf(buffer, "%d", static_cast<int>(time(0)));
cnonce = MD5(buffer);
ncount = "00000001";
std::string realm, nonce, qop, opaque;
HttpHasAttribute(args, "realm", &realm);
HttpHasAttribute(args, "nonce", &nonce);
bool has_qop = HttpHasAttribute(args, "qop", &qop);
bool has_opaque = HttpHasAttribute(args, "opaque", &opaque);
// TODO(bugs.webrtc.org/8905): Convert sensitive to a CryptString and also
// return response as CryptString so contents get securely deleted
// automatically.
// std::string A1 = username + ":" + realm + ":" + password;
size_t len = username.size() + realm.size() + password.GetLength() + 3;
char* sensitive = new char[len]; // A1
size_t pos = strcpyn(sensitive, len, username.data(), username.size());
pos += strcpyn(sensitive + pos, len - pos, ":");
pos += strcpyn(sensitive + pos, len - pos, realm.c_str());
pos += strcpyn(sensitive + pos, len - pos, ":");
password.CopyTo(sensitive + pos, true);
std::string A2 = method + ":" + uri;
std::string middle;
if (has_qop) {
qop = "auth";
middle = nonce + ":" + ncount + ":" + cnonce + ":" + qop;
} else {
middle = nonce;
}
std::string HA1 = MD5(sensitive);
ExplicitZeroMemory(sensitive, len);
delete[] sensitive;
std::string HA2 = MD5(A2);
std::string dig_response = MD5(HA1 + ":" + middle + ":" + HA2);
rtc::StringBuilder ss;
ss << auth_method;
ss << " username=" << quote(username);
ss << ", realm=" << quote(realm);
ss << ", nonce=" << quote(nonce);
ss << ", uri=" << quote(uri);
if (has_qop) {
ss << ", qop=" << qop;
ss << ", nc=" << ncount;
ss << ", cnonce=" << quote(cnonce);
}
ss << ", response=\"" << dig_response << "\"";
if (has_opaque) {
ss << ", opaque=" << quote(opaque);
}
response = ss.str();
return HAR_RESPONSE;
}
#if defined(WEBRTC_WIN)
#if 1
bool want_negotiate = (_stricmp(auth_method.c_str(), "negotiate") == 0);
bool want_ntlm = (_stricmp(auth_method.c_str(), "ntlm") == 0);
// SPNEGO & NTLM
if (want_negotiate || want_ntlm) {
const size_t MAX_MESSAGE = 12000, MAX_SPN = 256;
char out_buf[MAX_MESSAGE], spn[MAX_SPN];
#if 0 // Requires funky windows versions
DWORD len = MAX_SPN;
if (DsMakeSpn("HTTP", server.HostAsURIString().c_str(), nullptr,
server.port(),
0, &len, spn) != ERROR_SUCCESS) {
RTC_LOG_F(WARNING) << "(Negotiate) - DsMakeSpn failed";
return HAR_IGNORE;
}
#else
sprintfn(spn, MAX_SPN, "HTTP/%s", server.ToString().c_str());
#endif
SecBuffer out_sec;
out_sec.pvBuffer = out_buf;
out_sec.cbBuffer = sizeof(out_buf);
out_sec.BufferType = SECBUFFER_TOKEN;
SecBufferDesc out_buf_desc;
out_buf_desc.ulVersion = 0;
out_buf_desc.cBuffers = 1;
out_buf_desc.pBuffers = &out_sec;
const ULONG NEG_FLAGS_DEFAULT =
// ISC_REQ_ALLOCATE_MEMORY
ISC_REQ_CONFIDENTIALITY
//| ISC_REQ_EXTENDED_ERROR
//| ISC_REQ_INTEGRITY
| ISC_REQ_REPLAY_DETECT | ISC_REQ_SEQUENCE_DETECT
//| ISC_REQ_STREAM
//| ISC_REQ_USE_SUPPLIED_CREDS
;
::TimeStamp lifetime;
SECURITY_STATUS ret = S_OK;
ULONG ret_flags = 0, flags = NEG_FLAGS_DEFAULT;
bool specify_credentials = !username.empty();
size_t steps = 0;
// uint32_t now = Time();
NegotiateAuthContext* neg = static_cast<NegotiateAuthContext*>(context);
if (neg) {
const size_t max_steps = 10;
if (++neg->steps >= max_steps) {
RTC_LOG(WARNING) << "AsyncHttpsProxySocket::Authenticate(Negotiate) "
"too many retries";
return HAR_ERROR;
}
steps = neg->steps;
std::string challenge, decoded_challenge;
if (HttpHasNthAttribute(args, 1, &challenge, nullptr) &&
Base64::Decode(challenge, Base64::DO_STRICT, &decoded_challenge,
nullptr)) {
SecBuffer in_sec;
in_sec.pvBuffer = const_cast<char*>(decoded_challenge.data());
in_sec.cbBuffer = static_cast<unsigned long>(decoded_challenge.size());
in_sec.BufferType = SECBUFFER_TOKEN;
SecBufferDesc in_buf_desc;
in_buf_desc.ulVersion = 0;
in_buf_desc.cBuffers = 1;
in_buf_desc.pBuffers = &in_sec;
ret = InitializeSecurityContextA(
&neg->cred, &neg->ctx, spn, flags, 0, SECURITY_NATIVE_DREP,
&in_buf_desc, 0, &neg->ctx, &out_buf_desc, &ret_flags, &lifetime);
if (FAILED(ret)) {
RTC_LOG(LS_ERROR) << "InitializeSecurityContext returned: "
<< GetErrorName(ret, SECURITY_ERRORS);
return HAR_ERROR;
}
} else if (neg->specified_credentials) {
// Try again with default credentials
specify_credentials = false;
delete context;
context = neg = 0;
} else {
return HAR_CREDENTIALS;
}
}
if (!neg) {
unsigned char userbuf[256], passbuf[256], domainbuf[16];
SEC_WINNT_AUTH_IDENTITY_A auth_id, *pauth_id = 0;
if (specify_credentials) {
memset(&auth_id, 0, sizeof(auth_id));
size_t len = password.GetLength() + 1;
char* sensitive = new char[len];
password.CopyTo(sensitive, true);
std::string::size_type pos = username.find('\\');
if (pos == std::string::npos) {
auth_id.UserLength = static_cast<unsigned long>(
std::min(sizeof(userbuf) - 1, username.size()));
memcpy(userbuf, username.c_str(), auth_id.UserLength);
userbuf[auth_id.UserLength] = 0;
auth_id.DomainLength = 0;
domainbuf[auth_id.DomainLength] = 0;
auth_id.PasswordLength = static_cast<unsigned long>(
std::min(sizeof(passbuf) - 1, password.GetLength()));
memcpy(passbuf, sensitive, auth_id.PasswordLength);
passbuf[auth_id.PasswordLength] = 0;
} else {
auth_id.UserLength = static_cast<unsigned long>(
std::min(sizeof(userbuf) - 1, username.size() - pos - 1));
memcpy(userbuf, username.c_str() + pos + 1, auth_id.UserLength);
userbuf[auth_id.UserLength] = 0;
auth_id.DomainLength =
static_cast<unsigned long>(std::min(sizeof(domainbuf) - 1, pos));
memcpy(domainbuf, username.c_str(), auth_id.DomainLength);
domainbuf[auth_id.DomainLength] = 0;
auth_id.PasswordLength = static_cast<unsigned long>(
std::min(sizeof(passbuf) - 1, password.GetLength()));
memcpy(passbuf, sensitive, auth_id.PasswordLength);
passbuf[auth_id.PasswordLength] = 0;
}
ExplicitZeroMemory(sensitive, len);
delete[] sensitive;
auth_id.User = userbuf;
auth_id.Domain = domainbuf;
auth_id.Password = passbuf;
auth_id.Flags = SEC_WINNT_AUTH_IDENTITY_ANSI;
pauth_id = &auth_id;
RTC_LOG(LS_VERBOSE)
<< "Negotiate protocol: Using specified credentials";
} else {
RTC_LOG(LS_VERBOSE) << "Negotiate protocol: Using default credentials";
}
CredHandle cred;
ret = AcquireCredentialsHandleA(
0, const_cast<char*>(want_negotiate ? NEGOSSP_NAME_A : NTLMSP_NAME_A),
SECPKG_CRED_OUTBOUND, 0, pauth_id, 0, 0, &cred, &lifetime);
if (ret != SEC_E_OK) {
RTC_LOG(LS_ERROR) << "AcquireCredentialsHandle error: "
<< GetErrorName(ret, SECURITY_ERRORS);
return HAR_IGNORE;
}
// CSecBufferBundle<5, CSecBufferBase::FreeSSPI> sb_out;
CtxtHandle ctx;
ret = InitializeSecurityContextA(&cred, 0, spn, flags, 0,
SECURITY_NATIVE_DREP, 0, 0, &ctx,
&out_buf_desc, &ret_flags, &lifetime);
if (FAILED(ret)) {
RTC_LOG(LS_ERROR) << "InitializeSecurityContext returned: "
<< GetErrorName(ret, SECURITY_ERRORS);
FreeCredentialsHandle(&cred);
return HAR_IGNORE;
}
RTC_DCHECK(!context);
context = neg = new NegotiateAuthContext(auth_method, cred, ctx);
neg->specified_credentials = specify_credentials;
neg->steps = steps;
}
if ((ret == SEC_I_COMPLETE_NEEDED) ||
(ret == SEC_I_COMPLETE_AND_CONTINUE)) {
ret = CompleteAuthToken(&neg->ctx, &out_buf_desc);
RTC_LOG(LS_VERBOSE) << "CompleteAuthToken returned: "
<< GetErrorName(ret, SECURITY_ERRORS);
if (FAILED(ret)) {
return HAR_ERROR;
}
}
std::string decoded(out_buf, out_buf + out_sec.cbBuffer);
response = auth_method;
response.append(" ");
response.append(Base64::Encode(decoded));
return HAR_RESPONSE;
}
#endif
#endif // WEBRTC_WIN
return HAR_IGNORE;
}
//////////////////////////////////////////////////////////////////////
} // namespace rtc