/*

 * Copyright (c) 1998, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include "java.h"

#include "jvm_md.h"

#include <dirent.h>

#include <dlfcn.h>

#include <fcntl.h>

#include <inttypes.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <sys/stat.h>

#include <unistd.h>

#include <sys/types.h>

#include "manifest_info.h"

#define JVM_DLL "libjvm.so"

#define JAVA_DLL "libjava.so"

#ifdef AIX

#define LD_LIBRARY_PATH "LIBPATH"

#else

#define LD_LIBRARY_PATH "LD_LIBRARY_PATH"

#endif

/* help jettison the LD_LIBRARY_PATH settings in the future */

#ifndef SETENV_REQUIRED

#define SETENV_REQUIRED

#endif

#ifdef __solaris__

#  include <sys/systeminfo.h>

#  include <sys/elf.h>

#  include <stdio.h>

#endif

/*

 * Flowchart of launcher execs and options processing on unix

 *

 * The selection of the proper vm shared library to open depends on

 * several classes of command line options, including vm "flavor"

 * options (-client, -server).

 * The vm selection options are not passed to the running

 * virtual machine; they must be screened out by the launcher.

 *

 * The version specification (if any) is processed first by the

 * platform independent routine SelectVersion.  This may result in

 * the exec of the specified launcher version.

 *

 * Previously the launcher modified the LD_LIBRARY_PATH appropriately for the

 * desired data model path, regardless if data models matched or not. The

 * launcher subsequently exec'ed the desired executable, in order to make the

 * LD_LIBRARY_PATH path available, for the runtime linker.

 *

 * Now, in most cases,the launcher will dlopen the target libjvm.so. All

 * required libraries are loaded by the runtime linker, using the

 * $RPATH/$ORIGIN baked into the shared libraries at compile time. Therefore,

 * in most cases, the launcher will only exec, if the data models are

 * mismatched, and will not set any environment variables, regardless of the

 * data models.

 *

 * However, if the environment contains a LD_LIBRARY_PATH, this will cause the

 * launcher to inspect the LD_LIBRARY_PATH. The launcher will check

 *  a. if the LD_LIBRARY_PATH's first component is the path to the desired

 *     libjvm.so

 *  b. if any other libjvm.so is found in any of the paths.

 * If case b is true, then the launcher will set the LD_LIBRARY_PATH to the

 * desired JRE and reexec, in order to propagate the environment.

 *

 *  Main

 *  (incoming argv)

 *  |

 * \|/

 * CreateExecutionEnvironment

 * (determines desired data model)

 *  |

 *  |

 * \|/

 *  Have Desired Model ? --> NO --> Exit(with error)

 *  |

 *  |

 * \|/

 * YES

 *  |

 *  |

 * \|/

 * CheckJvmType

 * (removes -client, -server, etc.)

 *  |

 *  |

 * \|/

 * TranslateDashJArgs...

 * (Prepare to pass args to vm)

 *  |

 *  |

 * \|/

 * ParseArguments

 *   |

 *   |

 *  \|/

 * RequiresSetenv

 * Is LD_LIBRARY_PATH

 * and friends set ? --> NO --> Continue

 *  YES

 *   |

 *   |

 *  \|/

 * Path is desired JRE ? YES --> Continue

 *  NO

 *   |

 *   |

 *  \|/

 * Paths have well known

 * jvm paths ?       --> NO --> Error/Exit

 *  YES

 *   |

 *   |

 *  \|/

 *  Does libjvm.so exist

 *  in any of them ? --> NO  --> Continue

 *   YES

 *   |

 *   |

 *  \|/

 *  Set the LD_LIBRARY_PATH

 *   |

 *   |

 *  \|/

 * Re-exec

 *   |

 *   |

 *  \|/

 * Main

 */

/* Store the name of the executable once computed */

static char *execname = NULL;

/*

 * execname accessor from other parts of platform dependent logic

 */

const char *

GetExecName() {

    return execname;

}

#ifdef SETENV_REQUIRED

static jboolean

JvmExists(const char *path) {

    char tmp[PATH_MAX + 1];

    struct stat statbuf;

    JLI_Snprintf(tmp, PATH_MAX, "%s/%s", path, JVM_DLL);

    if (stat(tmp, &statbuf) == 0) {

        return JNI_TRUE;

    }

    return JNI_FALSE;

}

/*

 * contains a lib/{server,client}/libjvm.so ?

 */

static jboolean

ContainsLibJVM(const char *env) {

    /* the usual suspects */

    char clientPattern[] = "lib/client";

    char serverPattern[] = "lib/server";

    char *envpath;

    char *path;

    char* save_ptr = NULL;

    jboolean clientPatternFound;

    jboolean serverPatternFound;

    /* fastest path */

    if (env == NULL) {

        return JNI_FALSE;

    }

    /* to optimize for time, test if any of our usual suspects are present. */

    clientPatternFound = JLI_StrStr(env, clientPattern) != NULL;

    serverPatternFound = JLI_StrStr(env, serverPattern) != NULL;

    if (clientPatternFound == JNI_FALSE && serverPatternFound == JNI_FALSE) {

        return JNI_FALSE;

    }

    /*

     * we have a suspicious path component, check if it contains a libjvm.so

     */

    envpath = JLI_StringDup(env);

    for (path = strtok_r(envpath, ":", &save_ptr); path != NULL; path = strtok_r(NULL, ":", &save_ptr)) {

        if (clientPatternFound && JLI_StrStr(path, clientPattern) != NULL) {

            if (JvmExists(path)) {

                JLI_MemFree(envpath);

                return JNI_TRUE;

            }

        }

        if (serverPatternFound && JLI_StrStr(path, serverPattern)  != NULL) {

            if (JvmExists(path)) {

                JLI_MemFree(envpath);

                return JNI_TRUE;

            }

        }

    }

    JLI_MemFree(envpath);

    return JNI_FALSE;

}

/*

 * Test whether the environment variable needs to be set, see flowchart.

 */

static jboolean

RequiresSetenv(const char *jvmpath) {

    char jpath[PATH_MAX + 1];

    char *llp;

    char *dmllp = NULL;

    char *p; /* a utility pointer */

#ifdef AIX

    /* We always have to set the LIBPATH on AIX because ld doesn't support $ORIGIN. */

    return JNI_TRUE;

#endif

    llp = getenv("LD_LIBRARY_PATH");

#ifdef __solaris__

    dmllp = getenv("LD_LIBRARY_PATH_64");

#endif /* __solaris__ */

    /* no environment variable is a good environment variable */

    if (llp == NULL && dmllp == NULL) {

        return JNI_FALSE;

    }

#ifdef __linux

    /*

     * On linux, if a binary is running as sgid or suid, glibc sets

     * LD_LIBRARY_PATH to the empty string for security purposes. (In contrast,

     * on Solaris the LD_LIBRARY_PATH variable for a privileged binary does not

     * lose its settings; but the dynamic linker does apply more scrutiny to the

     * path.) The launcher uses the value of LD_LIBRARY_PATH to prevent an exec

     * loop, here and further downstream. Therefore, if we are running sgid or

     * suid, this function's setting of LD_LIBRARY_PATH will be ineffective and

     * we should case a return from the calling function.  Getting the right

     * libraries will be handled by the RPATH. In reality, this check is

     * redundant, as the previous check for a non-null LD_LIBRARY_PATH will

     * return back to the calling function forthwith, it is left here to safe

     * guard against any changes, in the glibc's existing security policy.

     */

    if ((getgid() != getegid()) || (getuid() != geteuid())) {

        return JNI_FALSE;

    }

#endif /* __linux */

    /*

     * Prevent recursions. Since LD_LIBRARY_PATH is the one which will be set by

     * previous versions of the JRE, thus it is the only path that matters here.

     * So we check to see if the desired JRE is set.

     */

    JLI_StrNCpy(jpath, jvmpath, PATH_MAX);

    p = JLI_StrRChr(jpath, '/');

    *p = '\0';

    if (llp != NULL && JLI_StrNCmp(llp, jpath, JLI_StrLen(jpath)) == 0) {

        return JNI_FALSE;

    }

    /* scrutinize all the paths further */

    if (llp != NULL &&  ContainsLibJVM(llp)) {

        return JNI_TRUE;

    }

    if (dmllp != NULL && ContainsLibJVM(dmllp)) {

        return JNI_TRUE;

    }

    return JNI_FALSE;

}

#endif /* SETENV_REQUIRED */

void

CreateExecutionEnvironment(int *pargc, char ***pargv,

                           char jrepath[], jint so_jrepath,

                           char jvmpath[], jint so_jvmpath,

                           char jvmcfg[],  jint so_jvmcfg) {

    char * jvmtype = NULL;

    int argc = *pargc;

    char **argv = *pargv;

#ifdef SETENV_REQUIRED

    jboolean mustsetenv = JNI_FALSE;

#ifdef __solaris__

    char *llp64 = NULL; /* existing LD_LIBRARY_PATH_64 setting */

#endif // __solaris__

    char *runpath = NULL; /* existing effective LD_LIBRARY_PATH setting */

    char* new_runpath = NULL; /* desired new LD_LIBRARY_PATH string */

    char* newpath = NULL; /* path on new LD_LIBRARY_PATH */

    char* lastslash = NULL;

    char** newenvp = NULL; /* current environment */

    size_t new_runpath_size;

#endif  /* SETENV_REQUIRED */

    /* Compute/set the name of the executable */

    SetExecname(*pargv);

    /* Check to see if the jvmpath exists */

    /* Find out where the JRE is that we will be using. */

    if (!GetJREPath(jrepath, so_jrepath, JNI_FALSE)) {

        JLI_ReportErrorMessage(JRE_ERROR1);

        exit(2);

    }

    JLI_Snprintf(jvmcfg, so_jvmcfg, "%s%slib%sjvm.cfg",

            jrepath, FILESEP, FILESEP);

    /* Find the specified JVM type */

    if (ReadKnownVMs(jvmcfg, JNI_FALSE) < 1) {

        JLI_ReportErrorMessage(CFG_ERROR7);

        exit(1);

    }

    jvmpath[0] = '\0';

    jvmtype = CheckJvmType(pargc, pargv, JNI_FALSE);

    if (JLI_StrCmp(jvmtype, "ERROR") == 0) {

        JLI_ReportErrorMessage(CFG_ERROR9);

        exit(4);

    }

    if (!GetJVMPath(jrepath, jvmtype, jvmpath, so_jvmpath)) {

        JLI_ReportErrorMessage(CFG_ERROR8, jvmtype, jvmpath);

        exit(4);

    }

    /*

     * we seem to have everything we need, so without further ado

     * we return back, otherwise proceed to set the environment.

     */

#ifdef SETENV_REQUIRED

    mustsetenv = RequiresSetenv(jvmpath);

    JLI_TraceLauncher("mustsetenv: %s\n", mustsetenv ? "TRUE" : "FALSE");

    if (mustsetenv == JNI_FALSE) {

        return;

    }

#else

    return;

#endif /* SETENV_REQUIRED */

#ifdef SETENV_REQUIRED

    if (mustsetenv) {

        /*

         * We will set the LD_LIBRARY_PATH as follows:

         *

         *     o          $JVMPATH (directory portion only)

         *     o          $JRE/lib

         *     o          $JRE/../lib

         *

         * followed by the user's previous effective LD_LIBRARY_PATH, if

         * any.

         */

#ifdef __solaris__

        llp64 = getenv("LD_LIBRARY_PATH_64");

        runpath = (llp64 == NULL) ? getenv(LD_LIBRARY_PATH) : llp64;

#else

        runpath = getenv(LD_LIBRARY_PATH);

#endif /* __solaris__ */

        /* runpath contains current effective LD_LIBRARY_PATH setting */

        { /* New scope to declare local variable */

            char *new_jvmpath = JLI_StringDup(jvmpath);

            new_runpath_size = ((runpath != NULL) ? JLI_StrLen(runpath) : 0) +

                    2 * JLI_StrLen(jrepath) +

                    JLI_StrLen(new_jvmpath) + 52;

            new_runpath = JLI_MemAlloc(new_runpath_size);

            newpath = new_runpath + JLI_StrLen(LD_LIBRARY_PATH "=");

            /*

             * Create desired LD_LIBRARY_PATH value for target data model.

             */

            {

                /* remove the name of the .so from the JVM path */

                lastslash = JLI_StrRChr(new_jvmpath, '/');

                if (lastslash)

                    *lastslash = '\0';

                sprintf(new_runpath, LD_LIBRARY_PATH "="

                        "%s:"

                        "%s/lib:"

                        "%s/../lib",

                        new_jvmpath,

                        jrepath,

                        jrepath

                        );

                JLI_MemFree(new_jvmpath);

                /*

                 * Check to make sure that the prefix of the current path is the

                 * desired environment variable setting, though the RequiresSetenv

                 * checks if the desired runpath exists, this logic does a more

                 * comprehensive check.

                 */

                if (runpath != NULL &&

                        JLI_StrNCmp(newpath, runpath, JLI_StrLen(newpath)) == 0 &&

                        (runpath[JLI_StrLen(newpath)] == 0 ||

                        runpath[JLI_StrLen(newpath)] == ':')) {

                    JLI_MemFree(new_runpath);

                    return;

                }

            }

        }

        /*

         * Place the desired environment setting onto the prefix of

         * LD_LIBRARY_PATH.  Note that this prevents any possible infinite

         * loop of execv() because we test for the prefix, above.

         */

        if (runpath != 0) {

            /* ensure storage for runpath + colon + NULL */

            if ((JLI_StrLen(runpath) + 1 + 1) > new_runpath_size) {

                JLI_ReportErrorMessageSys(JRE_ERROR11);

                exit(1);

            }

            JLI_StrCat(new_runpath, ":");

            JLI_StrCat(new_runpath, runpath);

        }

        if (putenv(new_runpath) != 0) {

            /* problem allocating memory; LD_LIBRARY_PATH not set properly */

            exit(1);

        }

        /*

         * Unix systems document that they look at LD_LIBRARY_PATH only

         * once at startup, so we have to re-exec the current executable

         * to get the changed environment variable to have an effect.

         */

#ifdef __solaris__

        /*

         * new LD_LIBRARY_PATH took over for LD_LIBRARY_PATH_64

         */

        if (llp64 != NULL) {

            UnsetEnv("LD_LIBRARY_PATH_64");

        }

#endif // __solaris__

        newenvp = environ;

    }

#endif /* SETENV_REQUIRED */

    {

        char *newexec = execname;

        JLI_TraceLauncher("TRACER_MARKER:About to EXEC\n");

        (void) fflush(stdout);

        (void) fflush(stderr);

#ifdef SETENV_REQUIRED

        if (mustsetenv) {

            execve(newexec, argv, newenvp);

        } else {

            execv(newexec, argv);

        }

#else /* !SETENV_REQUIRED */

        execv(newexec, argv);

#endif /* SETENV_REQUIRED */

        JLI_ReportErrorMessageSys(JRE_ERROR4, newexec);

    }

    exit(1);

}

static jboolean

GetJVMPath(const char *jrepath, const char *jvmtype,

           char *jvmpath, jint jvmpathsize)

{

    struct stat s;

    if (JLI_StrChr(jvmtype, '/')) {

        JLI_Snprintf(jvmpath, jvmpathsize, "%s/" JVM_DLL, jvmtype);

    } else {

        JLI_Snprintf(jvmpath, jvmpathsize, "%s/lib/%s/" JVM_DLL, jrepath, jvmtype);

    }

    JLI_TraceLauncher("Does `%s' exist ... ", jvmpath);

    if (stat(jvmpath, &s) == 0) {

        JLI_TraceLauncher("yes.\n");

        return JNI_TRUE;

    } else {

        JLI_TraceLauncher("no.\n");

        return JNI_FALSE;

    }

}

/*

 * Find path to JRE based on .exe's location or registry settings.

 */

static jboolean