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SoftEtherVPN/src/Cedar/Sam.c
Daiyuu Nobori bf4667cfce Fix several compile warnings on MS VC++ 2008.
2019-08-04 10:35:16 +09:00

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22 KiB
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// SoftEther VPN Source Code - Developer Edition Master Branch
// Cedar Communication Module
// Sam.c
// Security Accounts Manager
#include "CedarPch.h"
int base64_enc_len(unsigned int plainLen) {
unsigned int n = plainLen;
return (n + 2 - ((n + 2) % 3)) / 3 * 4;
}
PID OpenChildProcess(const char* path, char* const parameter[], int fd[] )
{
#ifdef OS_WIN32
// not implemented
return -1;
#else // OS_WIN32
// UNIX
int fds[2][2];
PID pid;
if (path == NULL || parameter == NULL || fd == NULL)
{
return (PID)-1;
}
if (pipe(fds[0]) != 0)
{
return (PID)-1;
}
if (pipe(fds[1]) != 0)
{
close(fds[0][0]);
close(fds[0][1]);
return (PID)-1;
}
pid = fork();
if (pid == (PID)0) {
int iError;
close(fds[0][1]);
close(fds[1][0]);
if (dup2(fds[0][0], fileno(stdin)) < 0 || dup2(fds[1][1], fileno(stdout)) < 0 )
{
close(fds[0][0]);
close(fds[1][1]);
_exit(EXIT_FAILURE);
}
iError = execvp(path, parameter);
// We should never come here
close(fds[0][0]);
close(fds[1][1]);
_exit(iError);
}
else if (pid > (PID)0)
{
close(fds[0][0]);
close(fds[1][1]);
fd[0] = fds[1][0];
fd[1] = fds[0][1];
return pid;
}
else
{
close(fds[0][0]);
close(fds[1][1]);
close(fds[0][1]);
close(fds[1][0]);
return -1;
}
#endif // OS_WIN32
}
void CloseChildProcess(PID pid, int* fd )
{
#ifdef OS_WIN32
// not implemented
#else // OS_WIN32
if( fd != 0 )
{
close(fd[0]);
close(fd[1]);
}
if( pid > 0 )
{
kill(pid, SIGTERM);
}
#endif // OS_WIN32
}
bool SmbAuthenticate(char* name, char* password, char* domainname, char* groupname, UINT timeout, UCHAR* challenge8, UCHAR* MsChapV2_ClientResponse, UCHAR* nt_pw_hash_hash)
{
bool auth = false;
int fds[2];
FILE* out, *in;
PID pid;
char buffer[255];
char ntlm_timeout[32];
char* proc_parameter[6];
if (name == NULL || password == NULL || domainname == NULL || groupname == NULL)
{
Debug("Sam.c - SmbAuthenticate - wrong password parameter\n");
return false;
}
if (password[0] == '\0' && (challenge8 == NULL || MsChapV2_ClientResponse == NULL || nt_pw_hash_hash == NULL))
{
Debug("Sam.c - SmbAuthenticate - wrong MsCHAPv2 parameter\n");
return false;
}
Zero(buffer, sizeof(buffer));
// Truncate string if unsafe char
EnSafeStr(domainname, '\0');
if (strlen(domainname) > 255)
{
// there is no domainname longer then 255 chars!
// http://tools.ietf.org/html/rfc1035 section 2.3.4
domainname[255] = '\0';
}
// set timeout to 15 minutes even if timeout is disabled, to prevent ntlm_auth from hung up
if (timeout <= 0 || timeout > 900)
{
timeout = 999;
}
snprintf(ntlm_timeout, sizeof(ntlm_timeout), "%is", timeout);
Debug("Sam.c - timeout for ntlm_auth %s\n", ntlm_timeout);
proc_parameter[0] = "timeout";
proc_parameter[1] = ntlm_timeout;
proc_parameter[2] = "ntlm_auth";
proc_parameter[3] = "--helper-protocol=ntlm-server-1";
proc_parameter[4] = 0;
if (strlen(groupname) > 1)
{
// DNS Name 255 chars + OU names are limited to 64 characters + cmdline 32 + 1
char requiremember[352];
// Truncate string if unsafe char
EnSafeStr(groupname, '\0');
snprintf(requiremember, sizeof(requiremember), "--require-membership-of=%s\\%s", domainname, groupname);
proc_parameter[4] = requiremember;
proc_parameter[5] = 0;
}
pid = OpenChildProcess("timeout", proc_parameter, fds);
if (pid < 0)
{
Debug("Sam.c - SmbCheckLogon - error fork child process (ntlm_auth)\n");
return false;
}
out = fdopen(fds[1], "w");
if (out == 0)
{
CloseChildProcess(pid, fds);
Debug("Sam.c - cant open out pipe (ntlm_auth)\n");
return false;
}
in = fdopen(fds[0], "r");
if (in == 0)
{
fclose(out);
CloseChildProcess(pid, fds);
Debug("Sam.c - cant open in pipe (ntlm_auth)\n");
return false;
}
if (base64_enc_len((unsigned int)strlen(name)) < sizeof(buffer)-1 &&
base64_enc_len((unsigned int)strlen(password)) < sizeof(buffer)-1 &&
base64_enc_len((unsigned int)strlen(domainname)) < sizeof(buffer)-1)
{
char answer[300];
unsigned int end = B64_Encode(buffer, name, (int)strlen(name));
buffer[end] = '\0';
fputs("Username:: ", out);
fputs(buffer, out);
fputs("\n", out);
Debug("Username: %s\n", buffer);
buffer[0] = 0;
end = B64_Encode(buffer, domainname, (int)strlen(domainname));
buffer[end] = '\0';
fputs("NT-Domain:: ", out);
fputs(buffer, out);
fputs("\n", out);
Debug("NT-Domain: %s\n", buffer);
buffer[0] = 0;
if (password[0] != '\0')
{
Debug("Password authentication\n");
end = B64_Encode(buffer, password, (int)strlen(password));
buffer[end] = '\0';
fputs("Password:: ", out);
fputs(buffer, out);
fputs("\n", out);
Debug("Password: %s\n", buffer);
buffer[0] = 0;
}
else
{
char* mschapv2_client_response;
char* base64_challenge8;
Debug("MsChapV2 authentication\n");
mschapv2_client_response = CopyBinToStr(MsChapV2_ClientResponse, 24);
end = B64_Encode(buffer, mschapv2_client_response, 48);
buffer[end] = '\0';
fputs("NT-Response:: ", out);
fputs(buffer, out);
fputs("\n", out);
Debug("NT-Response:: %s\n", buffer);
buffer[0] = 0;
Free(mschapv2_client_response);
base64_challenge8 = CopyBinToStr(challenge8, 8);
end = B64_Encode(buffer, base64_challenge8 , 16);
buffer[end] = '\0';
fputs("LANMAN-Challenge:: ", out);
fputs(buffer, out);
fputs("\n", out);
Debug("LANMAN-Challenge:: %s\n", buffer);
buffer[0] = 0;
Free(base64_challenge8);
fputs("Request-User-Session-Key: Yes\n", out);
}
// Start authentication
fputs( ".\n", out );
fflush (out);
// Request send!
Zero(answer, sizeof(answer));
while (fgets(answer, sizeof(answer)-1, in))
{
char* response_parameter;
if (strncmp(answer, ".\n", sizeof(answer)-1 ) == 0)
{
break;
}
/* Indicates a base64 encoded structure */
response_parameter = strstr(answer, ":: ");
if (!response_parameter) {
char* newline;
response_parameter = strstr(answer, ": ");
if (!response_parameter) {
continue;
}
response_parameter[0] ='\0';
response_parameter++;
response_parameter[0] ='\0';
response_parameter++;
newline = strstr(response_parameter, "\n");
if( newline )
newline[0] = '\0';
} else {
response_parameter[0] ='\0';
response_parameter++;
response_parameter[0] ='\0';
response_parameter++;
response_parameter[0] ='\0';
response_parameter++;
end = Decode64(response_parameter, response_parameter);
response_parameter[end] = '\0';
}
if (strncmp(answer, "Authenticated", sizeof(answer)-1 ) == 0)
{
if (strcmp(response_parameter, "Yes") == 0)
{
Debug("Authenticated!\n");
auth = true;
}
else if (strcmp(response_parameter, "No") == 0)
{
Debug("Authentication failed!\n");
auth = false;
}
}
else if (strncmp(answer, "User-Session-Key", sizeof(answer)-1 ) == 0)
{
if (nt_pw_hash_hash != NULL)
{
BUF* Buf = StrToBin(response_parameter);
Copy(nt_pw_hash_hash, Buf->Buf, 16);
FreeBuf(Buf);
}
}
}
}
fclose(in);
fclose(out);
CloseChildProcess(pid, fds);
return auth;
}
bool SmbCheckLogon(char* name, char* password, char* domainname, char* groupname, UINT timeout)
{
return SmbAuthenticate(name, password, domainname, groupname, timeout, NULL, NULL, NULL);
}
bool SmbPerformMsChapV2Auth(char* name, char* domainname, char* groupname, UCHAR* challenge8, UCHAR* MsChapV2_ClientResponse, UCHAR* nt_pw_hash_hash, UINT timeout)
{
return SmbAuthenticate(name, "", domainname, groupname, timeout, challenge8, MsChapV2_ClientResponse, nt_pw_hash_hash);
}
// Password encryption
void SecurePassword(void *secure_password, void *password, void *random)
{
BUF *b;
// Validate arguments
if (secure_password == NULL || password == NULL || random == NULL)
{
return;
}
b = NewBuf();
WriteBuf(b, password, SHA1_SIZE);
WriteBuf(b, random, SHA1_SIZE);
Sha0(secure_password, b->Buf, b->Size);
FreeBuf(b);
}
// Generate 160bit random number
void GenRandom(void *random)
{
// Validate arguments
if (random == NULL)
{
return;
}
Rand(random, SHA1_SIZE);
}
// Anonymous authentication of user
bool SamAuthUserByAnonymous(HUB *h, char *username)
{
bool b = false;
// Validate arguments
if (h == NULL || username == NULL)
{
return false;
}
AcLock(h);
{
USER *u = AcGetUser(h, username);
if (u)
{
Lock(u->lock);
{
if (u->AuthType == AUTHTYPE_ANONYMOUS)
{
b = true;
}
}
Unlock(u->lock);
}
ReleaseUser(u);
}
AcUnlock(h);
return b;
}
// Plaintext password authentication of user
bool SamAuthUserByPlainPassword(CONNECTION *c, HUB *hub, char *username, char *password, bool ast, UCHAR *mschap_v2_server_response_20, RADIUS_LOGIN_OPTION *opt)
{
bool b = false;
wchar_t *name = NULL;
wchar_t *groupname = NULL;
UINT timeout = 90;
bool auth_by_nt = false;
HUB *h;
// Validate arguments
if (hub == NULL || c == NULL || username == NULL)
{
return false;
}
if (GetGlobalServerFlag(GSF_DISABLE_RADIUS_AUTH) != 0)
{
return false;
}
h = hub;
AddRef(h->ref);
// Get the user name on authentication system
AcLock(hub);
{
USER *u;
u = AcGetUser(hub, ast == false ? username : "*");
if (u)
{
Lock(u->lock);
{
if (u->AuthType == AUTHTYPE_RADIUS)
{
// Radius authentication
AUTHRADIUS *auth = (AUTHRADIUS *)u->AuthData;
if (ast || auth->RadiusUsername == NULL || UniStrLen(auth->RadiusUsername) == 0)
{
if( IsEmptyStr(h->RadiusRealm) == false )
{
char name_and_realm[MAX_SIZE];
StrCpy(name_and_realm, sizeof(name_and_realm), username);
StrCat(name_and_realm, sizeof(name_and_realm), "@");
StrCat(name_and_realm, sizeof(name_and_realm), h->RadiusRealm);
name = CopyStrToUni(name_and_realm);
}
else
{
name = CopyStrToUni(username);
}
}
else
{
name = CopyUniStr(auth->RadiusUsername);
}
auth_by_nt = false;
}
else if (u->AuthType == AUTHTYPE_NT)
{
// NT authentication
AUTHNT *auth = (AUTHNT *)u->AuthData;
if (ast || auth->NtUsername == NULL || UniStrLen(auth->NtUsername) == 0)
{
name = CopyStrToUni(username);
}
else
{
name = CopyUniStr(auth->NtUsername);
}
groupname = CopyStrToUni(u->GroupName);
if (u->Policy)
{
timeout = u->Policy->TimeOut;
}
auth_by_nt = true;
}
}
Unlock(u->lock);
ReleaseUser(u);
}
}
AcUnlock(hub);
if (name != NULL)
{
if (auth_by_nt == false)
{
// Radius authentication
char radius_server_addr[MAX_SIZE];
UINT radius_server_port;
char radius_secret[MAX_SIZE];
char suffix_filter[MAX_SIZE];
wchar_t suffix_filter_w[MAX_SIZE];
UINT interval;
Zero(suffix_filter, sizeof(suffix_filter));
Zero(suffix_filter_w, sizeof(suffix_filter_w));
// Get the Radius server information
if (GetRadiusServerEx2(hub, radius_server_addr, sizeof(radius_server_addr), &radius_server_port, radius_secret, sizeof(radius_secret), &interval, suffix_filter, sizeof(suffix_filter)))
{
Unlock(hub->lock);
StrToUni(suffix_filter_w, sizeof(suffix_filter_w), suffix_filter);
if (UniIsEmptyStr(suffix_filter_w) || UniEndWith(name, suffix_filter_w))
{
// Attempt to login
b = RadiusLogin(c, radius_server_addr, radius_server_port,
radius_secret, StrLen(radius_secret),
name, password, interval, mschap_v2_server_response_20, opt, hub->Name);
if (b)
{
if (opt != NULL)
{
opt->Out_IsRadiusLogin = true;
}
}
}
Lock(hub->lock);
}
else
{
HLog(hub, "LH_NO_RADIUS_SETTING", name);
}
}
else
{
// NT authentication
#ifdef OS_WIN32
IPC_MSCHAP_V2_AUTHINFO mschap;
Unlock(hub->lock);
if (ParseAndExtractMsChapV2InfoFromPassword(&mschap, password) == false)
{
// Plaintext password authentication
b = MsCheckLogon(name, password);
}
else
{
UCHAR challenge8[8];
UCHAR nt_pw_hash_hash[16];
char nt_name[MAX_SIZE];
UniToStr(nt_name, sizeof(nt_name), name);
// MS-CHAPv2 authentication
MsChapV2_GenerateChallenge8(challenge8, mschap.MsChapV2_ClientChallenge,
mschap.MsChapV2_ServerChallenge,
mschap.MsChapV2_PPPUsername);
Debug("MsChapV2_PPPUsername = %s, nt_name = %s\n", mschap.MsChapV2_PPPUsername, nt_name);
b = MsPerformMsChapV2AuthByLsa(nt_name, challenge8, mschap.MsChapV2_ClientResponse, nt_pw_hash_hash);
if (b)
{
if (mschap_v2_server_response_20 != NULL)
{
MsChapV2Server_GenerateResponse(mschap_v2_server_response_20, nt_pw_hash_hash,
mschap.MsChapV2_ClientResponse, challenge8);
}
}
}
Lock(hub->lock);
#else // OS_WIN32
// Unix / Samba Winbind
IPC_MSCHAP_V2_AUTHINFO mschap;
Unlock(hub->lock);
char nt_name[MAX_SIZE];
char nt_username[MAX_SIZE];
char nt_groupname[MAX_SIZE];
char nt_domainname[MAX_SIZE];
UCHAR challenge8[8];
UCHAR nt_pw_hash_hash[16];
nt_groupname[0] = 0;
UniToStr(nt_name, sizeof(nt_name), name);
if (groupname != NULL)
UniToStr(nt_groupname, sizeof(nt_groupname), groupname);
ParseNtUsername(nt_name, nt_username, sizeof(nt_username), nt_domainname, sizeof(nt_domainname), false);
if (ParseAndExtractMsChapV2InfoFromPassword(&mschap, password) == false)
{
// Plaintext password authentication
b = SmbCheckLogon(nt_username, password, nt_domainname, nt_groupname, timeout);
}
else
{
// MS-CHAPv2 authentication
MsChapV2_GenerateChallenge8(challenge8, mschap.MsChapV2_ClientChallenge,
mschap.MsChapV2_ServerChallenge,
mschap.MsChapV2_PPPUsername);
Debug("MsChapV2_PPPUsername = %s, nt_name = %s\n", mschap.MsChapV2_PPPUsername, nt_name);
b = SmbPerformMsChapV2Auth(nt_username, nt_domainname, nt_groupname, challenge8, mschap.MsChapV2_ClientResponse, nt_pw_hash_hash, timeout);
if (b)
{
if (mschap_v2_server_response_20 != NULL)
{
MsChapV2Server_GenerateResponse(mschap_v2_server_response_20, nt_pw_hash_hash,
mschap.MsChapV2_ClientResponse, challenge8);
}
}
}
Lock(hub->lock);
#endif // OS_WIN32 / OS_LINUX
}
// Memory release
if( groupname != NULL )
Free(groupname);
Free(name);
}
ReleaseHub(h);
return b;
}
// Certificate authentication of user
bool SamAuthUserByCert(HUB *h, char *username, X *x)
{
bool b = false;
// Validate arguments
if (h == NULL || username == NULL || x == NULL)
{
return false;
}
if (GetGlobalServerFlag(GSF_DISABLE_CERT_AUTH) != 0)
{
return false;
}
// Check expiration date
if (CheckXDateNow(x) == false)
{
return false;
}
// Check the Certification Revocation List
if (IsValidCertInHub(h, x) == false)
{
// Bad
wchar_t tmp[MAX_SIZE * 2];
// Log the contents of the certificate
GetAllNameFromX(tmp, sizeof(tmp), x);
HLog(h, "LH_AUTH_NG_CERT", username, tmp);
return false;
}
AcLock(h);
{
USER *u;
u = AcGetUser(h, username);
if (u)
{
Lock(u->lock);
{
if (u->AuthType == AUTHTYPE_USERCERT)
{
// Check whether to matche with the registered certificate
AUTHUSERCERT *auth = (AUTHUSERCERT *)u->AuthData;
if (CompareX(auth->UserX, x))
{
b = true;
}
}
else if (u->AuthType == AUTHTYPE_ROOTCERT)
{
// Check whether the certificate has been signed by the root certificate
AUTHROOTCERT *auth = (AUTHROOTCERT *)u->AuthData;
if (h->HubDb != NULL)
{
LockList(h->HubDb->RootCertList);
{
X *root_cert;
root_cert = GetIssuerFromList(h->HubDb->RootCertList, x);
if (root_cert != NULL)
{
b = true;
if (auth->CommonName != NULL && UniIsEmptyStr(auth->CommonName) == false)
{
// Compare the CN
if (UniStrCmpi(x->subject_name->CommonName, auth->CommonName) != 0)
{
b = false;
}
}
if (auth->Serial != NULL && auth->Serial->size >= 1)
{
// Compare the serial number
if (CompareXSerial(x->serial, auth->Serial) == false)
{
b = false;
}
}
}
}
UnlockList(h->HubDb->RootCertList);
}
}
}
Unlock(u->lock);
ReleaseUser(u);
}
}
AcUnlock(h);
if (b)
{
wchar_t tmp[MAX_SIZE * 2];
// Log the contents of the certificate
GetAllNameFromX(tmp, sizeof(tmp), x);
HLog(h, "LH_AUTH_OK_CERT", username, tmp);
}
return b;
}
// Get the root certificate that signed the specified certificate from the list
X *GetIssuerFromList(LIST *cert_list, X *cert)
{
UINT i;
X *ret = NULL;
// Validate arguments
if (cert_list == NULL || cert == NULL)
{
return NULL;
}
for (i = 0;i < LIST_NUM(cert_list);i++)
{
X *x = LIST_DATA(cert_list, i);
// Name comparison
if (CheckXDateNow(x))
{
if (CompareName(x->subject_name, cert->issuer_name))
{
// Get the public key of the root certificate
K *k = GetKFromX(x);
if (k != NULL)
{
// Check the signature
if (CheckSignature(cert, k))
{
ret = x;
}
FreeK(k);
}
}
}
if (CompareX(x, cert))
{
// Complete identical
ret = x;
}
}
return ret;
}
// Get the policy to be applied for the user
POLICY *SamGetUserPolicy(HUB *h, char *username)
{
POLICY *ret = NULL;
// Validate arguments
if (h == NULL || username == NULL)
{
return NULL;
}
AcLock(h);
{
USER *u;
u = AcGetUser(h, username);
if (u)
{
USERGROUP *g = NULL;
Lock(u->lock);
{
if (u->Policy != NULL)
{
ret = ClonePolicy(u->Policy);
}
g = u->Group;
if (g != NULL)
{
AddRef(g->ref);
}
}
Unlock(u->lock);
ReleaseUser(u);
u = NULL;
if (ret == NULL)
{
if (g != NULL)
{
Lock(g->lock);
{
ret = ClonePolicy(g->Policy);
}
Unlock(g->lock);
}
}
if (g != NULL)
{
ReleaseGroup(g);
}
}
}
AcUnlock(h);
return ret;
}
// Password authentication of user
bool SamAuthUserByPassword(HUB *h, char *username, void *random, void *secure_password, char *mschap_v2_password, UCHAR *mschap_v2_server_response_20, UINT *err)
{
bool b = false;
UCHAR secure_password_check[SHA1_SIZE];
bool is_mschap = false;
IPC_MSCHAP_V2_AUTHINFO mschap;
UINT dummy = 0;
// Validate arguments
if (h == NULL || username == NULL || secure_password == NULL)
{
return false;
}
if (err == NULL)
{
err = &dummy;
}
*err = 0;
Zero(&mschap, sizeof(mschap));
is_mschap = ParseAndExtractMsChapV2InfoFromPassword(&mschap, mschap_v2_password);
if (StrCmpi(username, ADMINISTRATOR_USERNAME) == 0)
{
// Administrator mode
SecurePassword(secure_password_check, h->SecurePassword, random);
if (Cmp(secure_password_check, secure_password, SHA1_SIZE) == 0)
{
return true;
}
else
{
return false;
}
}
AcLock(h);
{
USER *u;
u = AcGetUser(h, username);
if (u)
{
Lock(u->lock);
{
if (u->AuthType == AUTHTYPE_PASSWORD)
{
AUTHPASSWORD *auth = (AUTHPASSWORD *)u->AuthData;
if (is_mschap == false)
{
// Normal password authentication
SecurePassword(secure_password_check, auth->HashedKey, random);
if (Cmp(secure_password_check, secure_password, SHA1_SIZE) == 0)
{
b = true;
}
}
else
{
// MS-CHAP v2 authentication via PPP
UCHAR challenge8[8];
UCHAR client_response[24];
if (IsZero(auth->NtLmSecureHash, MD5_SIZE))
{
// NTLM hash is not registered in the user account
*err = ERR_MSCHAP2_PASSWORD_NEED_RESET;
}
else
{
UCHAR nt_pw_hash_hash[16];
Zero(challenge8, sizeof(challenge8));
Zero(client_response, sizeof(client_response));
MsChapV2_GenerateChallenge8(challenge8, mschap.MsChapV2_ClientChallenge, mschap.MsChapV2_ServerChallenge,
mschap.MsChapV2_PPPUsername);
MsChapV2Client_GenerateResponse(client_response, challenge8, auth->NtLmSecureHash);
if (Cmp(client_response, mschap.MsChapV2_ClientResponse, 24) == 0)
{
// Hash matched
b = true;
// Calculate the response
GenerateNtPasswordHashHash(nt_pw_hash_hash, auth->NtLmSecureHash);
MsChapV2Server_GenerateResponse(mschap_v2_server_response_20, nt_pw_hash_hash,
client_response, challenge8);
}
}
}
}
}
Unlock(u->lock);
ReleaseUser(u);
}
}
AcUnlock(h);
return b;
}
// Make sure that the user exists
bool SamIsUser(HUB *h, char *username)
{
bool b;
// Validate arguments
if (h == NULL || username == NULL)
{
return false;
}
AcLock(h);
{
b = AcIsUser(h, username);
}
AcUnlock(h);
return b;
}
// Get the type of authentication used by the user
UINT SamGetUserAuthType(HUB *h, char *username)
{
UINT authtype;
// Validate arguments
if (h == NULL || username == NULL)
{
return INFINITE;
}
AcLock(h);
{
USER *u = AcGetUser(h, username);
if (u == NULL)
{
authtype = INFINITE;
}
else
{
authtype = u->AuthType;
ReleaseUser(u);
}
}
AcUnlock(h);
return authtype;
}
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