https://git.reactos.org/?p=reactos.git;a=commitdiff;h=e90e918039e60228d1c3e3...
commit e90e918039e60228d1c3e3a7e8bc016915dd49ac Author: George Bișoc george.bisoc@reactos.org AuthorDate: Thu Mar 10 12:03:31 2022 +0100 Commit: George Bișoc george.bisoc@reactos.org CommitDate: Fri May 6 10:09:50 2022 +0200
[ADVAPI32] Soft rewrite of CreateProcessAsUserCommon
Refactor the function in such a way that it can jump to a single exit but most importantly, implement a "rinse and repeat" mechanism where we assign a primary token to process by disabling impersonation first and retry with impersonation later.
More info can be found in the documention within the code. --- dll/win32/advapi32/misc/logon.c | 419 +++++++++++++++++++++++++++++++++------- 1 file changed, 352 insertions(+), 67 deletions(-)
diff --git a/dll/win32/advapi32/misc/logon.c b/dll/win32/advapi32/misc/logon.c index 1262f1b652d..6687a9f7e93 100644 --- a/dll/win32/advapi32/misc/logon.c +++ b/dll/win32/advapi32/misc/logon.c @@ -89,24 +89,221 @@ CloseLogonLsaHandle(VOID) }
+/** + * @brief + * Sets a primary token to the newly created process. + * The primary token that gets assigned to is a token + * whose security context is associated with the logged + * in user. For futher documentation information, see + * Remarks. + * + * @param[in] ImpersonateAsSelf + * If set to TRUE, the function will act on behalf of + * the calling process by impersonating its security context. + * Generally the caller will disable impersonation and attempt + * to act on behalf of the said main process as a first tentative + * to acquire the needed privilege in order to assign a token + * to the process. If set to FALSE, the function won't act on behalf + * of the calling process. + * + * @param[in] ProcessHandle + * A handle to the newly created process. The function will use it + * as a mean to assign the primary token to this process. + * + * @param[in] ThreadHandle + * A handle to the newly and primary created thread associated with + * the process. + * + * @param[in] DuplicatedTokenHandle + * A handle to a duplicated access token. This token represents as a primary + * one, initially duplicated in form as a primary type from an impersonation + * type. + * + * @return + * STATUS_SUCCESS is returned if token assignment to process succeeded, otherwise + * a failure NTSTATUS code is returned. A potential failure status code is + * STATUS_ACCESS_DENIED which means the caller doesn't have enough rights + * to grant access for primary token assignment to process. + * + * @remarks + * This function acts like an internal helper for CreateProcessAsUserCommon (and as + * such for CreateProcessAsUserW/A as well) as once a process is created, the + * function is tasked to assign the security context of the logged in user to + * that process. However, the rate of success of inserting the token into the + * process ultimately depends on the caller. + * + * The caller will either succeed or fail at acquiring SE_ASSIGNPRIMARYTOKEN_PRIVILEGE + * privilege depending on the security context of the user. If it's allowed, the caller + * would generally acquire such privilege immediately but if not, the caller will attempt + * to do a second try. + */ +static +NTSTATUS +InsertTokenToProcessCommon( + _In_ BOOL ImpersonateAsSelf, + _In_ HANDLE ProcessHandle, + _In_ HANDLE ThreadHandle, + _In_ HANDLE DuplicatedTokenHandle) +{ + NTSTATUS Status; + PROCESS_ACCESS_TOKEN AccessToken; + BOOLEAN PrivilegeSet; + BOOLEAN HavePrivilege; + + /* + * Assume the SE_ASSIGNPRIMARYTOKEN_PRIVILEGE + * privilege hasn't been set. + */ + PrivilegeSet = FALSE; + + /* + * The caller asked that we must impersonate as + * ourselves, that is, we'll be going to impersonate + * the security context of the calling process. If + * self impersonation fails then the caller has + * to do a "rinse and repeat" approach. + */ + if (ImpersonateAsSelf) + { + Status = RtlImpersonateSelf(SecurityImpersonation); + if (!NT_SUCCESS(Status)) + { + ERR("RtlImpersonateSelf(SecurityImpersonation) failed, Status 0x%08x\n", Status); + return Status; + } + } + + /* + * Attempt to acquire the process primary token assignment privilege + * in case we actually need it. + * The call will either succeed or fail when the caller has (or has not) + * enough rights. + * The last situation may not be dramatic for us. Indeed it may happen + * that the user-provided token is a restricted version of the caller's + * primary token (aka. a "child" token), or both tokens inherit (i.e. are + * children, and are together "siblings") from a common parent token. + * In this case the NT kernel allows us to assign the token to the child + * process without the need for the assignment privilege, which is fine. + * On the contrary, if the user-provided token is completely arbitrary, + * then the NT kernel will enforce the presence of the assignment privilege: + * because we failed (by assumption) to assign the privilege, the process + * token assignment will fail as required. It is then the job of the + * caller to manually acquire the necessary privileges. + */ + Status = RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE, + TRUE, TRUE, &PrivilegeSet); + HavePrivilege = NT_SUCCESS(Status); + if (!HavePrivilege) + { + ERR("RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE) failed, Status 0x%08lx, " + "attempting to continue without it...\n", Status); + } + + /* + * Assign the duplicated token and thread + * handle to the structure so that we'll + * use it to assign the primary token + * to process. + */ + AccessToken.Token = DuplicatedTokenHandle; + AccessToken.Thread = ThreadHandle; + + /* Set the new process token */ + Status = NtSetInformationProcess(ProcessHandle, + ProcessAccessToken, + (PVOID)&AccessToken, + sizeof(AccessToken)); + + /* Restore the privilege */ + if (HavePrivilege) + { + RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE, + PrivilegeSet, TRUE, &PrivilegeSet); + } + + /* + * Check again if the caller wanted to impersonate + * as self. If that is the case we must revert this + * impersonation back. + */ + if (ImpersonateAsSelf) + { + RevertToSelf(); + } + + /* + * Finally, check if we actually succeeded on assigning + * a primary token to the process. If we failed, oh well, + * asta la vista baby e arrivederci. The caller has to do + * a rinse and repeat approach. + */ + if (!NT_SUCCESS(Status)) + { + ERR("Failed to assign primary token to the process (Status 0x%08lx)\n", Status); + return Status; + } + + return STATUS_SUCCESS; +} + +/** + * @brief + * Internal function that serves as a helper for + * CreateProcessAsUserW/A routines on creating + * a process within the context of the logged in + * user. + * + * @param[in] hToken + * A handle to an access token that is associated + * with the logged in user. If the caller does not + * submit a token, the helper will immediately quit + * and return success, and the newly created process + * will be created upon using the default security + * context. + * + * @param[in] dwCreationFlags + * Bit masks containing the creation process flags. + * The function uses this parameter to determine + * if the process wasn't created in a suspended way + * and if not the function will resume the main thread. + * + * @param[in,out] lpProcessInformation + * A pointer to a structure that contains process creation + * information data. Such pointer contains the process + * and thread handles and whatnot. + * + * @return + * Returns TRUE if the helper has successfully assigned + * the newly created process the user's security context + * to that process, otherwise FALSE is returned. + * + * @remarks + * In order for the helper function to assign the primary + * token to the process, it has to do a "rinse and repeat" + * approach. That is, the helper will stop the impersonation + * and attempt to assign the token to process by acting + * on behalf of the main process' security context. If that + * fails, the function will do a second attempt by doing this + * but with impersonation enabled instead. + */ static BOOL CreateProcessAsUserCommon( _In_opt_ HANDLE hToken, _In_ DWORD dwCreationFlags, - _Out_ LPPROCESS_INFORMATION lpProcessInformation) + _Inout_ LPPROCESS_INFORMATION lpProcessInformation) { - NTSTATUS Status; - PROCESS_ACCESS_TOKEN AccessToken; + NTSTATUS Status = STATUS_SUCCESS, StatusOnExit; + BOOL Success; + TOKEN_TYPE Type; + ULONG ReturnLength; + OBJECT_ATTRIBUTES ObjectAttributes; + HANDLE hTokenDup = NULL; + HANDLE OriginalImpersonationToken = NULL; + HANDLE NullToken = NULL;
if (hToken != NULL) { - TOKEN_TYPE Type; - ULONG ReturnLength; - OBJECT_ATTRIBUTES ObjectAttributes; - HANDLE hTokenDup; - BOOLEAN PrivilegeSet = FALSE, HavePrivilege; - /* Check whether the user-provided token is a primary token */ // GetTokenInformation(); Status = NtQueryInformationToken(hToken, @@ -117,15 +314,59 @@ CreateProcessAsUserCommon( if (!NT_SUCCESS(Status)) { ERR("NtQueryInformationToken() failed, Status 0x%08x\n", Status); + Success = FALSE; goto Quit; } + if (Type != TokenPrimary) { ERR("Wrong token type for token 0x%p, expected TokenPrimary, got %ld\n", hToken, Type); Status = STATUS_BAD_TOKEN_TYPE; + Success = FALSE; goto Quit; }
+ /* + * Open the original token of the calling thread + * and halt the impersonation for the moment + * being. The opened thread token will be cached + * so that we will restore it back when we're done. + */ + Status = NtOpenThreadToken(NtCurrentThread(), + TOKEN_QUERY | TOKEN_IMPERSONATE, + TRUE, + &OriginalImpersonationToken); + if (!NT_SUCCESS(Status)) + { + /* We failed? Does this thread have a token at least? */ + OriginalImpersonationToken = NULL; + if (Status != STATUS_NO_TOKEN) + { + /* + * OK so this thread has a token but we + * could not open it for whatever reason. + * Bail out then. + */ + ERR("Failed to open thread token with 0x%08lx\n", Status); + Success = FALSE; + goto Quit; + } + } + else + { + /* We succeeded, stop the impersonation for now */ + Status = NtSetInformationThread(NtCurrentThread(), + ThreadImpersonationToken, + &NullToken, + sizeof(NullToken)); + if (!NT_SUCCESS(Status)) + { + ERR("Failed to stop impersonation with 0x%08lx\n", Status); + Success = FALSE; + goto Quit; + } + } + /* Duplicate the token for this new process */ InitializeObjectAttributes(&ObjectAttributes, NULL, @@ -141,79 +382,123 @@ CreateProcessAsUserCommon( if (!NT_SUCCESS(Status)) { ERR("NtDuplicateToken() failed, Status 0x%08x\n", Status); - goto Quit; - } - - // FIXME: Do we always need SecurityImpersonation? - Status = RtlImpersonateSelf(SecurityImpersonation); - if (!NT_SUCCESS(Status)) - { - ERR("RtlImpersonateSelf(SecurityImpersonation) failed, Status 0x%08x\n", Status); - NtClose(hTokenDup); + Success = FALSE; goto Quit; }
/* - * Attempt to acquire the process primary token assignment privilege - * in case we actually need it. - * The call will either succeed or fail when the caller has (or has not) - * enough rights. - * The last situation may not be dramatic for us. Indeed it may happen - * that the user-provided token is a restricted version of the caller's - * primary token (aka. a "child" token), or both tokens inherit (i.e. are - * children, and are together "siblings") from a common parent token. - * In this case the NT kernel allows us to assign the token to the child - * process without the need for the assignment privilege, which is fine. - * On the contrary, if the user-provided token is completely arbitrary, - * then the NT kernel will enforce the presence of the assignment privilege: - * because we failed (by assumption) to assign the privilege, the process - * token assignment will fail as required. It is then the job of the - * caller to manually acquire the necessary privileges. + * Now it's time to set the primary token into + * the process. On the first try, do it by + * impersonating the security context of the + * calling process (impersonate as self). */ - Status = RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE, - TRUE, TRUE, &PrivilegeSet); - HavePrivilege = NT_SUCCESS(Status); - if (!HavePrivilege) + Status = InsertTokenToProcessCommon(TRUE, + lpProcessInformation->hProcess, + lpProcessInformation->hThread, + hTokenDup); + if (!NT_SUCCESS(Status)) { - ERR("RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE) failed, Status 0x%08lx, " - "attempting to continue without it...\n", Status); - } - - AccessToken.Token = hTokenDup; - AccessToken.Thread = lpProcessInformation->hThread; + /* + * OK, we failed. Our second (and last try) is to not + * impersonate as self but instead we will try by setting + * the original impersonation (thread) token and set the + * primary token to the process through this way. This is + * what we call -- the "rinse and repeat" approach. + */ + Status = NtSetInformationThread(NtCurrentThread(), + ThreadImpersonationToken, + &OriginalImpersonationToken, + sizeof(OriginalImpersonationToken)); + if (!NT_SUCCESS(Status)) + { + ERR("Failed to restore impersonation token for setting process token, Status 0x%08lx\n", Status); + NtClose(hTokenDup); + Success = FALSE; + goto Quit; + }
- /* Set the new process token */ - Status = NtSetInformationProcess(lpProcessInformation->hProcess, - ProcessAccessToken, - (PVOID)&AccessToken, - sizeof(AccessToken)); + /* Retry again */ + Status = InsertTokenToProcessCommon(FALSE, + lpProcessInformation->hProcess, + lpProcessInformation->hThread, + hTokenDup); + if (!NT_SUCCESS(Status)) + { + /* Even the second try failed, bail out... */ + ERR("Failed to insert the primary token into process, Status 0x%08lx\n", Status); + NtClose(hTokenDup); + Success = FALSE; + goto Quit; + }
- /* Restore the privilege */ - if (HavePrivilege) - { - RtlAdjustPrivilege(SE_ASSIGNPRIMARYTOKEN_PRIVILEGE, - PrivilegeSet, TRUE, &PrivilegeSet); + /* All good, now stop impersonation */ + Status = NtSetInformationThread(NtCurrentThread(), + ThreadImpersonationToken, + &NullToken, + sizeof(NullToken)); + if (!NT_SUCCESS(Status)) + { + ERR("Failed to unset impersonationg token after setting process token, Status 0x%08lx\n", Status); + NtClose(hTokenDup); + Success = FALSE; + goto Quit; + } }
- RevertToSelf(); + /* + * FIXME: As we have successfully set up a primary token to + * the newly created process, we must set up as well a definite + * limit of quota charges for this process on the context of + * this user. + */
/* Close the duplicated token */ NtClose(hTokenDup); + Success = TRUE; + }
- /* Check whether NtSetInformationProcess() failed */ - if (!NT_SUCCESS(Status)) - { - ERR("NtSetInformationProcess() failed, Status 0x%08x\n", Status); - goto Quit; - } + /* + * If the caller did not supply a token then just declare + * ourselves as job done. The newly created process will use + * the default security context at this point anyway. + */ + TRACE("No token supplied, the process will use default security context!\n"); + Success = TRUE;
- if (!NT_SUCCESS(Status)) - { Quit: - TerminateProcess(lpProcessInformation->hProcess, Status); - SetLastError(RtlNtStatusToDosError(Status)); - return FALSE; - } + /* + * If we successfully opened the thread token before + * and stopped the impersonation then we have to assign + * its original token back and close that token we have + * referenced it. + */ + if (OriginalImpersonationToken != NULL) + { + StatusOnExit = NtSetInformationThread(NtCurrentThread(), + ThreadImpersonationToken, + &OriginalImpersonationToken, + sizeof(OriginalImpersonationToken)); + + /* + * We really must assert ourselves that we successfully + * set the original token back, otherwise if we fail + * then something is seriously going wrong.... + * The status code is cached in a separate status + * variable because we would not want to tamper + * with the original status code that could have been + * returned by someone else above in this function code. + */ + ASSERT(NT_SUCCESS(StatusOnExit)); + + /* De-reference it */ + NtClose(OriginalImpersonationToken); + } + + /* Terminate the process and set the last error status */ + if (!NT_SUCCESS(Status)) + { + TerminateProcess(lpProcessInformation->hProcess, Status); + SetLastError(RtlNtStatusToDosError(Status)); }
/* Resume the main thread */ @@ -222,7 +507,7 @@ Quit: ResumeThread(lpProcessInformation->hThread); }
- return TRUE; + return Success; }
-
George Bișoc