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Diffstat (limited to '')
| -rw-r--r-- | src/VBox/Runtime/r3/posix/process-creation-posix.cpp | 1191 |
1 files changed, 1191 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r3/posix/process-creation-posix.cpp b/src/VBox/Runtime/r3/posix/process-creation-posix.cpp new file mode 100644 index 00000000..36e1ed99 --- /dev/null +++ b/src/VBox/Runtime/r3/posix/process-creation-posix.cpp @@ -0,0 +1,1191 @@ +/* $Id: process-creation-posix.cpp $ */ +/** @file + * IPRT - Process Creation, POSIX. + */ + +/* + * Copyright (C) 2006-2019 Oracle Corporation + * + * This file is part of VirtualBox Open Source Edition (OSE), as + * available from http://www.virtualbox.org. This file is free software; + * you can redistribute it and/or modify it under the terms of the GNU + * General Public License (GPL) as published by the Free Software + * Foundation, in version 2 as it comes in the "COPYING" file of the + * VirtualBox OSE distribution. VirtualBox OSE is distributed in the + * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL) only, as it comes in the "COPYING.CDDL" file of the + * VirtualBox OSE distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#define LOG_GROUP RTLOGGROUP_PROCESS +#include <iprt/cdefs.h> + +#include <unistd.h> +#include <stdlib.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/wait.h> +#include <fcntl.h> +#include <signal.h> +#include <grp.h> +#include <pwd.h> +#if defined(RT_OS_LINUX) || defined(RT_OS_SOLARIS) +# include <crypt.h> +# include <shadow.h> +#endif + +#if defined(RT_OS_LINUX) || defined(RT_OS_OS2) +/* While Solaris has posix_spawn() of course we don't want to use it as + * we need to have the child in a different process contract, no matter + * whether it is started detached or not. */ +# define HAVE_POSIX_SPAWN 1 +#endif +#if defined(RT_OS_DARWIN) && defined(MAC_OS_X_VERSION_MIN_REQUIRED) +# if MAC_OS_X_VERSION_MIN_REQUIRED >= 1050 +# define HAVE_POSIX_SPAWN 1 +# endif +#endif +#ifdef HAVE_POSIX_SPAWN +# include <spawn.h> +#endif + +#ifdef RT_OS_DARWIN +# include <mach-o/dyld.h> +# include <security/pam_appl.h> +# include <stdlib.h> +# include <dlfcn.h> +# include <iprt/asm.h> +#endif + +#ifdef RT_OS_SOLARIS +# include <limits.h> +# include <sys/ctfs.h> +# include <sys/contract/process.h> +# include <libcontract.h> +#endif + +#ifndef RT_OS_SOLARIS +# include <paths.h> +#else +# define _PATH_MAILDIR "/var/mail" +# define _PATH_DEFPATH "/usr/bin:/bin" +# define _PATH_STDPATH "/sbin:/usr/sbin:/bin:/usr/bin" +#endif + + +#include <iprt/process.h> +#include "internal/iprt.h" + +#include <iprt/assert.h> +#include <iprt/env.h> +#include <iprt/err.h> +#include <iprt/file.h> +#include <iprt/log.h> +#include <iprt/path.h> +#include <iprt/pipe.h> +#include <iprt/socket.h> +#include <iprt/string.h> +#include <iprt/mem.h> +#include "internal/process.h" + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ +#ifdef RT_OS_DARWIN +/** For passing info between rtCheckCredentials and rtPamConv. */ +typedef struct RTPROCPAMARGS +{ + const char *pszUser; + const char *pszPassword; +} RTPROCPAMARGS; +/** Pointer to rtPamConv argument package. */ +typedef RTPROCPAMARGS *PRTPROCPAMARGS; +#endif + + +#ifdef RT_OS_DARWIN +/** + * Worker for rtCheckCredentials that feeds password and maybe username to PAM. + * + * @returns PAM status. + * @param cMessages Number of messages. + * @param papMessages Message vector. + * @param ppaResponses Where to put our responses. + * @param pvAppData Pointer to RTPROCPAMARGS. + */ +static int rtPamConv(int cMessages, const struct pam_message **papMessages, struct pam_response **ppaResponses, void *pvAppData) +{ + LogFlow(("rtPamConv: cMessages=%d\n", cMessages)); + PRTPROCPAMARGS pArgs = (PRTPROCPAMARGS)pvAppData; + AssertPtrReturn(pArgs, PAM_CONV_ERR); + + struct pam_response *paResponses = (struct pam_response *)calloc(cMessages, sizeof(paResponses[0])); + AssertReturn(paResponses, PAM_CONV_ERR); + for (int i = 0; i < cMessages; i++) + { + LogFlow(("rtPamConv: #%d: msg_style=%d msg=%s\n", i, papMessages[i]->msg_style, papMessages[i]->msg)); + + paResponses[i].resp_retcode = 0; + if (papMessages[i]->msg_style == PAM_PROMPT_ECHO_OFF) + paResponses[i].resp = strdup(pArgs->pszPassword); + else if (papMessages[i]->msg_style == PAM_PROMPT_ECHO_ON) + paResponses[i].resp = strdup(pArgs->pszUser); + else + { + paResponses[i].resp = NULL; + continue; + } + if (paResponses[i].resp == NULL) + { + while (i-- > 0) + free(paResponses[i].resp); + free(paResponses); + LogFlow(("rtPamConv: out of memory\n")); + return PAM_CONV_ERR; + } + } + + *ppaResponses = paResponses; + return PAM_SUCCESS; +} +#endif /* RT_OS_DARWIN */ + + +/** + * Check the credentials and return the gid/uid of user. + * + * @param pszUser username + * @param pszPasswd password + * @param gid where to store the GID of the user + * @param uid where to store the UID of the user + * @returns IPRT status code + */ +static int rtCheckCredentials(const char *pszUser, const char *pszPasswd, gid_t *pGid, uid_t *pUid) +{ +#if defined(RT_OS_DARWIN) + RTLogPrintf("rtCheckCredentials\n"); + + /* + * Resolve user to UID and GID. + */ + char szBuf[_4K]; + struct passwd Pw; + struct passwd *pPw; + if (getpwnam_r(pszUser, &Pw, szBuf, sizeof(szBuf), &pPw) != 0) + return VERR_AUTHENTICATION_FAILURE; + if (!pPw) + return VERR_AUTHENTICATION_FAILURE; + + *pUid = pPw->pw_uid; + *pGid = pPw->pw_gid; + + /* + * Use PAM for the authentication. + * Note! libpam.2.dylib was introduced with 10.6.x (OpenPAM). + */ + void *hModPam = dlopen("libpam.dylib", RTLD_LAZY | RTLD_GLOBAL); + if (hModPam) + { + int (*pfnPamStart)(const char *, const char *, struct pam_conv *, pam_handle_t **); + int (*pfnPamAuthenticate)(pam_handle_t *, int); + int (*pfnPamAcctMgmt)(pam_handle_t *, int); + int (*pfnPamSetItem)(pam_handle_t *, int, const void *); + int (*pfnPamEnd)(pam_handle_t *, int); + *(void **)&pfnPamStart = dlsym(hModPam, "pam_start"); + *(void **)&pfnPamAuthenticate = dlsym(hModPam, "pam_authenticate"); + *(void **)&pfnPamAcctMgmt = dlsym(hModPam, "pam_acct_mgmt"); + *(void **)&pfnPamSetItem = dlsym(hModPam, "pam_set_item"); + *(void **)&pfnPamEnd = dlsym(hModPam, "pam_end"); + ASMCompilerBarrier(); + if ( pfnPamStart + && pfnPamAuthenticate + && pfnPamAcctMgmt + && pfnPamSetItem + && pfnPamEnd) + { +#define pam_start pfnPamStart +#define pam_authenticate pfnPamAuthenticate +#define pam_acct_mgmt pfnPamAcctMgmt +#define pam_set_item pfnPamSetItem +#define pam_end pfnPamEnd + + /* Do the PAM stuff. + Note! Abusing 'login' here for now... */ + pam_handle_t *hPam = NULL; + RTPROCPAMARGS PamConvArgs = { pszUser, pszPasswd }; + struct pam_conv PamConversation; + RT_ZERO(PamConversation); + PamConversation.appdata_ptr = &PamConvArgs; + PamConversation.conv = rtPamConv; + int rc = pam_start("login", pszUser, &PamConversation, &hPam); + if (rc == PAM_SUCCESS) + { + rc = pam_set_item(hPam, PAM_RUSER, pszUser); + if (rc == PAM_SUCCESS) + rc = pam_authenticate(hPam, 0); + if (rc == PAM_SUCCESS) + { + rc = pam_acct_mgmt(hPam, 0); + if ( rc == PAM_SUCCESS + || rc == PAM_AUTHINFO_UNAVAIL /*??*/) + { + pam_end(hPam, PAM_SUCCESS); + dlclose(hModPam); + return VINF_SUCCESS; + } + Log(("rtCheckCredentials: pam_acct_mgmt -> %d\n", rc)); + } + else + Log(("rtCheckCredentials: pam_authenticate -> %d\n", rc)); + pam_end(hPam, rc); + } + else + Log(("rtCheckCredentials: pam_start -> %d\n", rc)); + } + else + Log(("rtCheckCredentials: failed to resolve symbols: %p %p %p %p %p\n", + pfnPamStart, pfnPamAuthenticate, pfnPamAcctMgmt, pfnPamSetItem, pfnPamEnd)); + dlclose(hModPam); + } + else + Log(("rtCheckCredentials: Loading libpam.dylib failed\n")); + return VERR_AUTHENTICATION_FAILURE; + +#elif defined(RT_OS_LINUX) + struct passwd *pw; + + pw = getpwnam(pszUser); + if (!pw) + return VERR_AUTHENTICATION_FAILURE; + + if (!pszPasswd) + pszPasswd = ""; + + struct spwd *spwd; + /* works only if /etc/shadow is accessible */ + spwd = getspnam(pszUser); + if (spwd) + pw->pw_passwd = spwd->sp_pwdp; + + /* Default fCorrect=true if no password specified. In that case, pw->pw_passwd + * must be NULL (no password set for this user). Fail if a password is specified + * but the user does not have one assigned. */ + int fCorrect = !pszPasswd || !*pszPasswd; + if (pw->pw_passwd && *pw->pw_passwd) + { + struct crypt_data *data = (struct crypt_data*)RTMemTmpAllocZ(sizeof(*data)); + /* be reentrant */ + char *pszEncPasswd = crypt_r(pszPasswd, pw->pw_passwd, data); + fCorrect = pszEncPasswd && !strcmp(pszEncPasswd, pw->pw_passwd); + RTMemTmpFree(data); + } + if (!fCorrect) + return VERR_AUTHENTICATION_FAILURE; + + *pGid = pw->pw_gid; + *pUid = pw->pw_uid; + return VINF_SUCCESS; + +#elif defined(RT_OS_SOLARIS) + struct passwd *ppw, pw; + char szBuf[1024]; + + if (getpwnam_r(pszUser, &pw, szBuf, sizeof(szBuf), &ppw) != 0 || ppw == NULL) + return VERR_AUTHENTICATION_FAILURE; + + if (!pszPasswd) + pszPasswd = ""; + + struct spwd spwd; + char szPwdBuf[1024]; + /* works only if /etc/shadow is accessible */ + if (getspnam_r(pszUser, &spwd, szPwdBuf, sizeof(szPwdBuf)) != NULL) + ppw->pw_passwd = spwd.sp_pwdp; + + char *pszEncPasswd = crypt(pszPasswd, ppw->pw_passwd); + if (strcmp(pszEncPasswd, ppw->pw_passwd)) + return VERR_AUTHENTICATION_FAILURE; + + *pGid = ppw->pw_gid; + *pUid = ppw->pw_uid; + return VINF_SUCCESS; + +#else + NOREF(pszUser); NOREF(pszPasswd); NOREF(pGid); NOREF(pUid); + return VERR_AUTHENTICATION_FAILURE; +#endif +} + +#ifdef RT_OS_SOLARIS + +/** @todo the error reporting of the Solaris process contract code could be + * a lot better, but essentially it is not meant to run into errors after + * the debugging phase. */ +static int rtSolarisContractPreFork(void) +{ + int templateFd = open64(CTFS_ROOT "/process/template", O_RDWR); + if (templateFd < 0) + return -1; + + /* Set template parameters and event sets. */ + if (ct_pr_tmpl_set_param(templateFd, CT_PR_PGRPONLY)) + { + close(templateFd); + return -1; + } + if (ct_pr_tmpl_set_fatal(templateFd, CT_PR_EV_HWERR)) + { + close(templateFd); + return -1; + } + if (ct_tmpl_set_critical(templateFd, 0)) + { + close(templateFd); + return -1; + } + if (ct_tmpl_set_informative(templateFd, CT_PR_EV_HWERR)) + { + close(templateFd); + return -1; + } + + /* Make this the active template for the process. */ + if (ct_tmpl_activate(templateFd)) + { + close(templateFd); + return -1; + } + + return templateFd; +} + +static void rtSolarisContractPostForkChild(int templateFd) +{ + if (templateFd == -1) + return; + + /* Clear the active template. */ + ct_tmpl_clear(templateFd); + close(templateFd); +} + +static void rtSolarisContractPostForkParent(int templateFd, pid_t pid) +{ + if (templateFd == -1) + return; + + /* Clear the active template. */ + int cleared = ct_tmpl_clear(templateFd); + close(templateFd); + + /* If the clearing failed or the fork failed there's nothing more to do. */ + if (cleared || pid <= 0) + return; + + /* Look up the contract which was created by this thread. */ + int statFd = open64(CTFS_ROOT "/process/latest", O_RDONLY); + if (statFd == -1) + return; + ct_stathdl_t statHdl; + if (ct_status_read(statFd, CTD_COMMON, &statHdl)) + { + close(statFd); + return; + } + ctid_t ctId = ct_status_get_id(statHdl); + ct_status_free(statHdl); + close(statFd); + if (ctId < 0) + return; + + /* Abandon this contract we just created. */ + char ctlPath[PATH_MAX]; + size_t len = snprintf(ctlPath, sizeof(ctlPath), + CTFS_ROOT "/process/%ld/ctl", (long)ctId); + if (len >= sizeof(ctlPath)) + return; + int ctlFd = open64(ctlPath, O_WRONLY); + if (statFd == -1) + return; + if (ct_ctl_abandon(ctlFd) < 0) + { + close(ctlFd); + return; + } + close(ctlFd); +} + +#endif /* RT_OS_SOLARIS */ + + +RTR3DECL(int) RTProcCreate(const char *pszExec, const char * const *papszArgs, RTENV Env, unsigned fFlags, PRTPROCESS pProcess) +{ + return RTProcCreateEx(pszExec, papszArgs, Env, fFlags, + NULL, NULL, NULL, /* standard handles */ + NULL /*pszAsUser*/, NULL /* pszPassword*/, + pProcess); +} + + +/** + * Adjust the profile environment after forking the child process and changing + * the UID. + * + * @returns IRPT status code. + * @param hEnvToUse The environment we're going to use with execve. + * @param fFlags The process creation flags. + * @param hEnv The environment passed in by the user. + */ +static int rtProcPosixAdjustProfileEnvFromChild(RTENV hEnvToUse, uint32_t fFlags, RTENV hEnv) +{ + int rc = VINF_SUCCESS; +#ifdef RT_OS_DARWIN + if ( RT_SUCCESS(rc) + && (!(fFlags & RTPROC_FLAGS_ENV_CHANGE_RECORD) || RTEnvExistEx(hEnv, "TMPDIR")) ) + { + char szValue[_4K]; + size_t cbNeeded = confstr(_CS_DARWIN_USER_TEMP_DIR, szValue, sizeof(szValue)); + if (cbNeeded > 0 && cbNeeded < sizeof(szValue)) + { + char *pszTmp; + rc = RTStrCurrentCPToUtf8(&pszTmp, szValue); + if (RT_SUCCESS(rc)) + { + rc = RTEnvSetEx(hEnvToUse, "TMPDIR", pszTmp); + RTStrFree(pszTmp); + } + } + else + rc = VERR_BUFFER_OVERFLOW; + } +#else + RT_NOREF_PV(hEnvToUse); RT_NOREF_PV(fFlags); RT_NOREF_PV(hEnv); +#endif + return rc; +} + + +/** + * Create a very very basic environment for a user. + * + * @returns IPRT status code. + * @param phEnvToUse Where to return the created environment. + * @param pszUser The user name for the profile. + */ +static int rtProcPosixCreateProfileEnv(PRTENV phEnvToUse, const char *pszUser) +{ + struct passwd Pwd; + struct passwd *pPwd = NULL; + char achBuf[_4K]; + int rc; + errno = 0; + if (pszUser) + rc = getpwnam_r(pszUser, &Pwd, achBuf, sizeof(achBuf), &pPwd); + else + rc = getpwuid_r(getuid(), &Pwd, achBuf, sizeof(achBuf), &pPwd); + if (rc == 0 && pPwd) + { + char *pszDir; + rc = RTStrCurrentCPToUtf8(&pszDir, pPwd->pw_dir); + if (RT_SUCCESS(rc)) + { + char *pszShell; + rc = RTStrCurrentCPToUtf8(&pszShell, pPwd->pw_shell); + if (RT_SUCCESS(rc)) + { + char *pszUserFree = NULL; + if (!pszUser) + { + rc = RTStrCurrentCPToUtf8(&pszUserFree, pPwd->pw_name); + if (RT_SUCCESS(rc)) + pszUser = pszUserFree; + } + if (RT_SUCCESS(rc)) + { + rc = RTEnvCreate(phEnvToUse); + if (RT_SUCCESS(rc)) + { + RTENV hEnvToUse = *phEnvToUse; + + rc = RTEnvSetEx(hEnvToUse, "HOME", pszDir); + if (RT_SUCCESS(rc)) + rc = RTEnvSetEx(hEnvToUse, "SHELL", pszShell); + if (RT_SUCCESS(rc)) + rc = RTEnvSetEx(hEnvToUse, "USER", pszUser); + if (RT_SUCCESS(rc)) + rc = RTEnvSetEx(hEnvToUse, "LOGNAME", pszUser); + + if (RT_SUCCESS(rc)) + rc = RTEnvSetEx(hEnvToUse, "PATH", pPwd->pw_uid == 0 ? _PATH_STDPATH : _PATH_DEFPATH); + + if (RT_SUCCESS(rc)) + { + RTStrPrintf(achBuf, sizeof(achBuf), "%s/%s", _PATH_MAILDIR, pszUser); + rc = RTEnvSetEx(hEnvToUse, "MAIL", achBuf); + } + +#ifdef RT_OS_DARWIN + if (RT_SUCCESS(rc) && !pszUserFree) + { + size_t cbNeeded = confstr(_CS_DARWIN_USER_TEMP_DIR, achBuf, sizeof(achBuf)); + if (cbNeeded > 0 && cbNeeded < sizeof(achBuf)) + { + char *pszTmp; + rc = RTStrCurrentCPToUtf8(&pszTmp, achBuf); + if (RT_SUCCESS(rc)) + { + rc = RTEnvSetEx(hEnvToUse, "TMPDIR", pszTmp); + RTStrFree(pszTmp); + } + } + else + rc = VERR_BUFFER_OVERFLOW; + } +#endif + + /** @todo load /etc/environment, /etc/profile.env and ~/.pam_environment? */ + + if (RT_FAILURE(rc)) + RTEnvDestroy(hEnvToUse); + } + RTStrFree(pszUserFree); + } + RTStrFree(pszShell); + } + RTStrFree(pszDir); + } + } + else + rc = errno ? RTErrConvertFromErrno(errno) : VERR_ACCESS_DENIED; + return rc; +} + + +/** + * RTPathTraverseList callback used by RTProcCreateEx to locate the executable. + */ +static DECLCALLBACK(int) rtPathFindExec(char const *pchPath, size_t cchPath, void *pvUser1, void *pvUser2) +{ + const char *pszExec = (const char *)pvUser1; + char *pszRealExec = (char *)pvUser2; + int rc = RTPathJoinEx(pszRealExec, RTPATH_MAX, pchPath, cchPath, pszExec, RTSTR_MAX); + if (RT_FAILURE(rc)) + return rc; + if (!access(pszRealExec, X_OK)) + return VINF_SUCCESS; + if ( errno == EACCES + || errno == EPERM) + return RTErrConvertFromErrno(errno); + return VERR_TRY_AGAIN; +} + +/** + * Cleans up the environment on the way out. + */ +static int rtProcPosixCreateReturn(int rc, RTENV hEnvToUse, RTENV hEnv) +{ + if (hEnvToUse != hEnv) + RTEnvDestroy(hEnvToUse); + return rc; +} + + +RTR3DECL(int) RTProcCreateEx(const char *pszExec, const char * const *papszArgs, RTENV hEnv, uint32_t fFlags, + PCRTHANDLE phStdIn, PCRTHANDLE phStdOut, PCRTHANDLE phStdErr, const char *pszAsUser, + const char *pszPassword, PRTPROCESS phProcess) +{ + int rc; + LogFlow(("RTProcCreateEx: pszExec=%s pszAsUser=%s\n", pszExec, pszAsUser)); + + /* + * Input validation + */ + AssertPtrReturn(pszExec, VERR_INVALID_POINTER); + AssertReturn(*pszExec, VERR_INVALID_PARAMETER); + AssertReturn(!(fFlags & ~RTPROC_FLAGS_VALID_MASK), VERR_INVALID_PARAMETER); + AssertReturn(!(fFlags & RTPROC_FLAGS_DETACHED) || !phProcess, VERR_INVALID_PARAMETER); + AssertReturn(hEnv != NIL_RTENV, VERR_INVALID_PARAMETER); + AssertPtrReturn(papszArgs, VERR_INVALID_PARAMETER); + AssertPtrNullReturn(pszAsUser, VERR_INVALID_POINTER); + AssertReturn(!pszAsUser || *pszAsUser, VERR_INVALID_PARAMETER); + AssertReturn(!pszPassword || pszAsUser, VERR_INVALID_PARAMETER); + AssertPtrNullReturn(pszPassword, VERR_INVALID_POINTER); +#if defined(RT_OS_OS2) + if (fFlags & RTPROC_FLAGS_DETACHED) + return VERR_PROC_DETACH_NOT_SUPPORTED; +#endif + + /* + * Get the file descriptors for the handles we've been passed. + */ + PCRTHANDLE paHandles[3] = { phStdIn, phStdOut, phStdErr }; + int aStdFds[3] = { -1, -1, -1 }; + for (int i = 0; i < 3; i++) + { + if (paHandles[i]) + { + AssertPtrReturn(paHandles[i], VERR_INVALID_POINTER); + switch (paHandles[i]->enmType) + { + case RTHANDLETYPE_FILE: + aStdFds[i] = paHandles[i]->u.hFile != NIL_RTFILE + ? (int)RTFileToNative(paHandles[i]->u.hFile) + : -2 /* close it */; + break; + + case RTHANDLETYPE_PIPE: + aStdFds[i] = paHandles[i]->u.hPipe != NIL_RTPIPE + ? (int)RTPipeToNative(paHandles[i]->u.hPipe) + : -2 /* close it */; + break; + + case RTHANDLETYPE_SOCKET: + aStdFds[i] = paHandles[i]->u.hSocket != NIL_RTSOCKET + ? (int)RTSocketToNative(paHandles[i]->u.hSocket) + : -2 /* close it */; + break; + + default: + AssertMsgFailedReturn(("%d: %d\n", i, paHandles[i]->enmType), VERR_INVALID_PARAMETER); + } + /** @todo check the close-on-execness of these handles? */ + } + } + + for (int i = 0; i < 3; i++) + if (aStdFds[i] == i) + aStdFds[i] = -1; + + for (int i = 0; i < 3; i++) + AssertMsgReturn(aStdFds[i] < 0 || aStdFds[i] > i, + ("%i := %i not possible because we're lazy\n", i, aStdFds[i]), + VERR_NOT_SUPPORTED); + + /* + * Resolve the user id if specified. + */ + uid_t uid = ~(uid_t)0; + gid_t gid = ~(gid_t)0; + if (pszAsUser) + { + rc = rtCheckCredentials(pszAsUser, pszPassword, &gid, &uid); + if (RT_FAILURE(rc)) + return rc; + } + + /* + * Create the child environment if either RTPROC_FLAGS_PROFILE or + * RTPROC_FLAGS_ENV_CHANGE_RECORD are in effect. + */ + RTENV hEnvToUse = hEnv; + if ( (fFlags & (RTPROC_FLAGS_ENV_CHANGE_RECORD | RTPROC_FLAGS_PROFILE)) + && ( (fFlags & RTPROC_FLAGS_ENV_CHANGE_RECORD) + || hEnv == RTENV_DEFAULT) ) + { + if (fFlags & RTPROC_FLAGS_PROFILE) + rc = rtProcPosixCreateProfileEnv(&hEnvToUse, pszAsUser); + else + rc = RTEnvClone(&hEnvToUse, RTENV_DEFAULT); + if (RT_SUCCESS(rc)) + { + if ((fFlags & RTPROC_FLAGS_ENV_CHANGE_RECORD) && hEnv != RTENV_DEFAULT) + rc = RTEnvApplyChanges(hEnvToUse, hEnv); + if (RT_FAILURE(rc)) + RTEnvDestroy(hEnvToUse); + } + if (RT_FAILURE(rc)) + return rc; + } + + /* + * Check for execute access to the file. + */ + char szRealExec[RTPATH_MAX]; + if (access(pszExec, X_OK)) + { + rc = errno; + if ( !(fFlags & RTPROC_FLAGS_SEARCH_PATH) + || rc != ENOENT + || RTPathHavePath(pszExec) ) + rc = RTErrConvertFromErrno(rc); + else + { + /* search */ + char *pszPath = RTEnvDupEx(hEnvToUse, "PATH"); + rc = RTPathTraverseList(pszPath, ':', rtPathFindExec, (void *)pszExec, &szRealExec[0]); + RTStrFree(pszPath); + if (RT_SUCCESS(rc)) + pszExec = szRealExec; + else + rc = rc == VERR_END_OF_STRING ? VERR_FILE_NOT_FOUND : rc; + } + + if (RT_FAILURE(rc)) + return rtProcPosixCreateReturn(rc, hEnvToUse, hEnv); + } + + pid_t pid = -1; + const char * const *papszEnv = RTEnvGetExecEnvP(hEnvToUse); + AssertPtrReturn(papszEnv, rtProcPosixCreateReturn(VERR_INVALID_HANDLE, hEnvToUse, hEnv)); + + + /* + * Take care of detaching the process. + * + * HACK ALERT! Put the process into a new process group with pgid = pid + * to make sure it differs from that of the parent process to ensure that + * the IPRT waitpid call doesn't race anyone (read XPCOM) doing group wide + * waits. setsid() includes the setpgid() functionality. + * 2010-10-11 XPCOM no longer waits for anything, but it cannot hurt. + */ +#ifndef RT_OS_OS2 + if (fFlags & RTPROC_FLAGS_DETACHED) + { +# ifdef RT_OS_SOLARIS + int templateFd = -1; + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + { + templateFd = rtSolarisContractPreFork(); + if (templateFd == -1) + return rtProcPosixCreateReturn(VERR_OPEN_FAILED, hEnvToUse, hEnv); + } +# endif /* RT_OS_SOLARIS */ + pid = fork(); + if (!pid) + { +# ifdef RT_OS_SOLARIS + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + rtSolarisContractPostForkChild(templateFd); +# endif + setsid(); /* see comment above */ + + pid = -1; + /* Child falls through to the actual spawn code below. */ + } + else + { +# ifdef RT_OS_SOLARIS + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + rtSolarisContractPostForkParent(templateFd, pid); +# endif + if (pid > 0) + { + /* Must wait for the temporary process to avoid a zombie. */ + int status = 0; + pid_t pidChild = 0; + + /* Restart if we get interrupted. */ + do + { + pidChild = waitpid(pid, &status, 0); + } while ( pidChild == -1 + && errno == EINTR); + + /* Assume that something wasn't found. No detailed info. */ + if (status) + return rtProcPosixCreateReturn(VERR_PROCESS_NOT_FOUND, hEnvToUse, hEnv); + if (phProcess) + *phProcess = 0; + return rtProcPosixCreateReturn(VINF_SUCCESS, hEnvToUse, hEnv); + } + return rtProcPosixCreateReturn(RTErrConvertFromErrno(errno), hEnvToUse, hEnv); + } + } +#endif + + /* + * Spawn the child. + * + * Any spawn code MUST not execute any atexit functions if it is for a + * detached process. It would lead to running the atexit functions which + * make only sense for the parent. libORBit e.g. gets confused by multiple + * execution. Remember, there was only a fork() so far, and until exec() + * is successfully run there is nothing which would prevent doing anything + * silly with the (duplicated) file descriptors. + */ +#ifdef HAVE_POSIX_SPAWN + /** @todo OS/2: implement DETACHED (BACKGROUND stuff), see VbglR3Daemonize. */ + if ( uid == ~(uid_t)0 + && gid == ~(gid_t)0) + { + /* Spawn attributes. */ + posix_spawnattr_t Attr; + rc = posix_spawnattr_init(&Attr); + if (!rc) + { + /* Indicate that process group and signal mask are to be changed, + and that the child should use default signal actions. */ + rc = posix_spawnattr_setflags(&Attr, POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF); + Assert(rc == 0); + + /* The child starts in its own process group. */ + if (!rc) + { + rc = posix_spawnattr_setpgroup(&Attr, 0 /* pg == child pid */); + Assert(rc == 0); + } + + /* Unmask all signals. */ + if (!rc) + { + sigset_t SigMask; + sigemptyset(&SigMask); + rc = posix_spawnattr_setsigmask(&Attr, &SigMask); Assert(rc == 0); + } + + /* File changes. */ + posix_spawn_file_actions_t FileActions; + posix_spawn_file_actions_t *pFileActions = NULL; + if ((aStdFds[0] != -1 || aStdFds[1] != -1 || aStdFds[2] != -1) && !rc) + { + rc = posix_spawn_file_actions_init(&FileActions); + if (!rc) + { + pFileActions = &FileActions; + for (int i = 0; i < 3; i++) + { + int fd = aStdFds[i]; + if (fd == -2) + rc = posix_spawn_file_actions_addclose(&FileActions, i); + else if (fd >= 0 && fd != i) + { + rc = posix_spawn_file_actions_adddup2(&FileActions, fd, i); + if (!rc) + { + for (int j = i + 1; j < 3; j++) + if (aStdFds[j] == fd) + { + fd = -1; + break; + } + if (fd >= 0) + rc = posix_spawn_file_actions_addclose(&FileActions, fd); + } + } + if (rc) + break; + } + } + } + + if (!rc) + rc = posix_spawn(&pid, pszExec, pFileActions, &Attr, (char * const *)papszArgs, + (char * const *)papszEnv); + + /* cleanup */ + int rc2 = posix_spawnattr_destroy(&Attr); Assert(rc2 == 0); NOREF(rc2); + if (pFileActions) + { + rc2 = posix_spawn_file_actions_destroy(pFileActions); + Assert(rc2 == 0); + } + + /* return on success.*/ + if (!rc) + { + /* For a detached process this happens in the temp process, so + * it's not worth doing anything as this process must exit. */ + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(0); + if (phProcess) + *phProcess = pid; + return rtProcPosixCreateReturn(VINF_SUCCESS, hEnvToUse, hEnv); + } + } + /* For a detached process this happens in the temp process, so + * it's not worth doing anything as this process must exit. */ + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(124); + } + else +#endif + { +#ifdef RT_OS_SOLARIS + int templateFd = -1; + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + { + templateFd = rtSolarisContractPreFork(); + if (templateFd == -1) + return rtProcPosixCreateReturn(VERR_OPEN_FAILED, hEnvToUse, hEnv); + } +#endif /* RT_OS_SOLARIS */ + pid = fork(); + if (!pid) + { +#ifdef RT_OS_SOLARIS + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + rtSolarisContractPostForkChild(templateFd); +#endif /* RT_OS_SOLARIS */ + if (!(fFlags & RTPROC_FLAGS_DETACHED)) + setpgid(0, 0); /* see comment above */ + + /* + * Change group and user if requested. + */ +#if 1 /** @todo This needs more work, see suplib/hardening. */ + if (pszAsUser) + { + int ret = initgroups(pszAsUser, gid); + if (ret) + { + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(126); + else + exit(126); + } + } + if (gid != ~(gid_t)0) + { + if (setgid(gid)) + { + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(126); + else + exit(126); + } + } + + if (uid != ~(uid_t)0) + { + if (setuid(uid)) + { + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(126); + else + exit(126); + } + } +#endif + + /* + * Some final profile environment tweaks, if running as user. + */ + if ( (fFlags & RTPROC_FLAGS_PROFILE) + && pszAsUser + && ( (fFlags & RTPROC_FLAGS_ENV_CHANGE_RECORD) + || hEnv == RTENV_DEFAULT) ) + { + rc = rtProcPosixAdjustProfileEnvFromChild(hEnvToUse, fFlags, hEnv); + papszEnv = RTEnvGetExecEnvP(hEnvToUse); + if (RT_FAILURE(rc) || !papszEnv) + { + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(126); + else + exit(126); + } + } + + /* + * Unset the signal mask. + */ + sigset_t SigMask; + sigemptyset(&SigMask); + rc = sigprocmask(SIG_SETMASK, &SigMask, NULL); + Assert(rc == 0); + + /* + * Apply changes to the standard file descriptor and stuff. + */ + for (int i = 0; i < 3; i++) + { + int fd = aStdFds[i]; + if (fd == -2) + close(i); + else if (fd >= 0) + { + int rc2 = dup2(fd, i); + if (rc2 != i) + { + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(125); + else + exit(125); + } + for (int j = i + 1; j < 3; j++) + if (aStdFds[j] == fd) + { + fd = -1; + break; + } + if (fd >= 0) + close(fd); + } + } + + /* + * Finally, execute the requested program. + */ + rc = execve(pszExec, (char * const *)papszArgs, (char * const *)papszEnv); + if (errno == ENOEXEC) + { + /* This can happen when trying to start a shell script without the magic #!/bin/sh */ + RTAssertMsg2Weak("Cannot execute this binary format!\n"); + } + else + RTAssertMsg2Weak("execve returns %d errno=%d\n", rc, errno); + RTAssertReleasePanic(); + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(127); + else + exit(127); + } +#ifdef RT_OS_SOLARIS + if (!(fFlags & RTPROC_FLAGS_SAME_CONTRACT)) + rtSolarisContractPostForkParent(templateFd, pid); +#endif /* RT_OS_SOLARIS */ + if (pid > 0) + { + /* For a detached process this happens in the temp process, so + * it's not worth doing anything as this process must exit. */ + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(0); + if (phProcess) + *phProcess = pid; + return rtProcPosixCreateReturn(VINF_SUCCESS, hEnvToUse, hEnv); + } + /* For a detached process this happens in the temp process, so + * it's not worth doing anything as this process must exit. */ + if (fFlags & RTPROC_FLAGS_DETACHED) + _Exit(124); + return rtProcPosixCreateReturn(RTErrConvertFromErrno(errno), hEnvToUse, hEnv); + } + + return rtProcPosixCreateReturn(VERR_NOT_IMPLEMENTED, hEnvToUse, hEnv); +} + + +RTR3DECL(int) RTProcDaemonizeUsingFork(bool fNoChDir, bool fNoClose, const char *pszPidfile) +{ + /* + * Fork the child process in a new session and quit the parent. + * + * - fork once and create a new session (setsid). This will detach us + * from the controlling tty meaning that we won't receive the SIGHUP + * (or any other signal) sent to that session. + * - The SIGHUP signal is ignored because the session/parent may throw + * us one before we get to the setsid. + * - When the parent exit(0) we will become an orphan and re-parented to + * the init process. + * - Because of the sometimes unexpected semantics of assigning the + * controlling tty automagically when a session leader first opens a tty, + * we will fork() once more to get rid of the session leadership role. + */ + + /* We start off by opening the pidfile, so that we can fail straight away + * if it already exists. */ + int fdPidfile = -1; + if (pszPidfile != NULL) + { + /* @note the exclusive create is not guaranteed on all file + * systems (e.g. NFSv2) */ + if ((fdPidfile = open(pszPidfile, O_RDWR | O_CREAT | O_EXCL, 0644)) == -1) + return RTErrConvertFromErrno(errno); + } + + /* Ignore SIGHUP straight away. */ + struct sigaction OldSigAct; + struct sigaction SigAct; + memset(&SigAct, 0, sizeof(SigAct)); + SigAct.sa_handler = SIG_IGN; + int rcSigAct = sigaction(SIGHUP, &SigAct, &OldSigAct); + + /* First fork, to become independent process. */ + pid_t pid = fork(); + if (pid == -1) + { + if (fdPidfile != -1) + close(fdPidfile); + return RTErrConvertFromErrno(errno); + } + if (pid != 0) + { + /* Parent exits, no longer necessary. The child gets reparented + * to the init process. */ + exit(0); + } + + /* Create new session, fix up the standard file descriptors and the + * current working directory. */ + /** @todo r=klaus the webservice uses this function and assumes that the + * contract id of the daemon is the same as that of the original process. + * Whenever this code is changed this must still remain possible. */ + pid_t newpgid = setsid(); + int SavedErrno = errno; + if (rcSigAct != -1) + sigaction(SIGHUP, &OldSigAct, NULL); + if (newpgid == -1) + { + if (fdPidfile != -1) + close(fdPidfile); + return RTErrConvertFromErrno(SavedErrno); + } + + if (!fNoClose) + { + /* Open stdin(0), stdout(1) and stderr(2) as /dev/null. */ + int fd = open("/dev/null", O_RDWR); + if (fd == -1) /* paranoia */ + { + close(STDIN_FILENO); + close(STDOUT_FILENO); + close(STDERR_FILENO); + fd = open("/dev/null", O_RDWR); + } + if (fd != -1) + { + dup2(fd, STDIN_FILENO); + dup2(fd, STDOUT_FILENO); + dup2(fd, STDERR_FILENO); + if (fd > 2) + close(fd); + } + } + + if (!fNoChDir) + { + int rcIgnored = chdir("/"); + NOREF(rcIgnored); + } + + /* Second fork to lose session leader status. */ + pid = fork(); + if (pid == -1) + { + if (fdPidfile != -1) + close(fdPidfile); + return RTErrConvertFromErrno(errno); + } + + if (pid != 0) + { + /* Write the pid file, this is done in the parent, before exiting. */ + if (fdPidfile != -1) + { + char szBuf[256]; + size_t cbPid = RTStrPrintf(szBuf, sizeof(szBuf), "%d\n", pid); + ssize_t cbIgnored = write(fdPidfile, szBuf, cbPid); NOREF(cbIgnored); + close(fdPidfile); + } + exit(0); + } + + if (fdPidfile != -1) + close(fdPidfile); + + return VINF_SUCCESS; +} + |