Adding upstream version 2.4.38.upstream/2.4.38

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 685 insertions, 0 deletions

diff --git a/support/suexec.c b/support/suexec.c
new file mode 100644
index 0000000..0b52495
--- /dev/null
+++ b/support/suexec.c
@@ -0,0 +1,685 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * suexec.c -- "Wrapper" support program for suEXEC behaviour for Apache
+ *
+ ***********************************************************************
+ *
+ * NOTE! : DO NOT edit this code!!!  Unless you know what you are doing,
+ *         editing this code might open up your system in unexpected
+ *         ways to would-be crackers.  Every precaution has been taken
+ *         to make this code as safe as possible; alter it at your own
+ *         risk.
+ *
+ ***********************************************************************
+ *
+ *
+ */
+
+#include "apr.h"
+#include "ap_config.h"
+#include "suexec.h"
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <string.h>
+#include <time.h>
+#if APR_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#if APR_HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
+#ifdef HAVE_PWD_H
+#include <pwd.h>
+#endif
+
+#ifdef HAVE_GRP_H
+#include <grp.h>
+#endif
+
+#ifdef AP_LOG_SYSLOG
+#include <syslog.h>
+#endif
+
+#if defined(PATH_MAX)
+#define AP_MAXPATH PATH_MAX
+#elif defined(MAXPATHLEN)
+#define AP_MAXPATH MAXPATHLEN
+#else
+#define AP_MAXPATH 8192
+#endif
+
+#define AP_ENVBUF 256
+
+extern char **environ;
+
+#ifdef AP_LOG_SYSLOG
+/* Syslog support. */
+#if !defined(AP_LOG_FACILITY) && defined(LOG_AUTHPRIV)
+#define AP_LOG_FACILITY LOG_AUTHPRIV
+#elif !defined(AP_LOG_FACILITY)
+#define AP_LOG_FACILITY LOG_AUTH
+#endif
+
+static int log_open;
+#else
+/* Non-syslog support. */
+static FILE *log = NULL;
+#endif
+
+static const char *const safe_env_lst[] =
+{
+    /* variable name starts with */
+    "HTTP_",
+    "SSL_",
+
+    /* variable name is */
+    "AUTH_TYPE=",
+    "CONTENT_LENGTH=",
+    "CONTENT_TYPE=",
+    "CONTEXT_DOCUMENT_ROOT=",
+    "CONTEXT_PREFIX=",
+    "DATE_GMT=",
+    "DATE_LOCAL=",
+    "DOCUMENT_ARGS=",
+    "DOCUMENT_NAME=",
+    "DOCUMENT_PATH_INFO=",
+    "DOCUMENT_ROOT=",
+    "DOCUMENT_URI=",
+    "GATEWAY_INTERFACE=",
+    "HTTPS=",
+    "LAST_MODIFIED=",
+    "PATH_INFO=",
+    "PATH_TRANSLATED=",
+    "QUERY_STRING=",
+    "QUERY_STRING_UNESCAPED=",
+    "REMOTE_ADDR=",
+    "REMOTE_HOST=",
+    "REMOTE_IDENT=",
+    "REMOTE_PORT=",
+    "REMOTE_USER=",
+    "REDIRECT_ERROR_NOTES=",
+    "REDIRECT_HANDLER=",
+    "REDIRECT_QUERY_STRING=",
+    "REDIRECT_REMOTE_USER=",
+    "REDIRECT_SCRIPT_FILENAME=",
+    "REDIRECT_STATUS=",
+    "REDIRECT_URL=",
+    "REQUEST_METHOD=",
+    "REQUEST_URI=",
+    "REQUEST_SCHEME=",
+    "SCRIPT_FILENAME=",
+    "SCRIPT_NAME=",
+    "SCRIPT_URI=",
+    "SCRIPT_URL=",
+    "SERVER_ADMIN=",
+    "SERVER_NAME=",
+    "SERVER_ADDR=",
+    "SERVER_PORT=",
+    "SERVER_PROTOCOL=",
+    "SERVER_SIGNATURE=",
+    "SERVER_SOFTWARE=",
+    "UNIQUE_ID=",
+    "USER_NAME=",
+    "TZ=",
+    NULL
+};
+
+static void log_err(const char *fmt,...) 
+    __attribute__((format(printf,1,2)));
+static void log_no_err(const char *fmt,...)  
+    __attribute__((format(printf,1,2)));
+static void err_output(int is_error, const char *fmt, va_list ap) 
+    __attribute__((format(printf,2,0)));
+
+static void err_output(int is_error, const char *fmt, va_list ap)
+{
+#if defined(AP_LOG_SYSLOG)
+    if (!log_open) {
+        openlog("suexec", LOG_PID, AP_LOG_FACILITY);
+        log_open = 1;
+    }
+
+    vsyslog(is_error ? LOG_ERR : LOG_INFO, fmt, ap);
+#elif defined(AP_LOG_EXEC)
+    time_t timevar;
+    struct tm *lt;
+
+    if (!log) {
+#if defined(_LARGEFILE64_SOURCE) && HAVE_FOPEN64
+        if ((log = fopen64(AP_LOG_EXEC, "a")) == NULL) {
+#else
+        if ((log = fopen(AP_LOG_EXEC, "a")) == NULL) {
+#endif
+            fprintf(stderr, "suexec failure: could not open log file\n");
+            perror("fopen");
+            exit(1);
+        }
+    }
+
+    if (is_error) {
+        fprintf(stderr, "suexec policy violation: see suexec log for more "
+                        "details\n");
+    }
+
+    time(&timevar);
+    lt = localtime(&timevar);
+
+    fprintf(log, "[%d-%.2d-%.2d %.2d:%.2d:%.2d]: ",
+            lt->tm_year + 1900, lt->tm_mon + 1, lt->tm_mday,
+            lt->tm_hour, lt->tm_min, lt->tm_sec);
+
+    vfprintf(log, fmt, ap);
+
+    fflush(log);
+#endif /* AP_LOG_EXEC */
+    return;
+}
+
+static void log_err(const char *fmt,...)
+{
+#ifdef AP_LOG_EXEC
+    va_list ap;
+
+    va_start(ap, fmt);
+    err_output(1, fmt, ap); /* 1 == is_error */
+    va_end(ap);
+#endif /* AP_LOG_EXEC */
+    return;
+}
+
+static void log_no_err(const char *fmt,...)
+{
+#ifdef AP_LOG_EXEC
+    va_list ap;
+
+    va_start(ap, fmt);
+    err_output(0, fmt, ap); /* 0 == !is_error */
+    va_end(ap);
+#endif /* AP_LOG_EXEC */
+    return;
+}
+
+static void clean_env(void)
+{
+    char pathbuf[512];
+    char **cleanenv;
+    char **ep;
+    int cidx = 0;
+    int idx;
+
+    /* While cleaning the environment, the environment should be clean.
+     * (e.g. malloc() may get the name of a file for writing debugging info.
+     * Bad news if MALLOC_DEBUG_FILE is set to /etc/passwd.  Sprintf() may be
+     * susceptible to bad locale settings....)
+     * (from PR 2790)
+     */
+    char **envp = environ;
+    char *empty_ptr = NULL;
+
+    environ = &empty_ptr; /* VERY safe environment */
+
+    if ((cleanenv = (char **) calloc(AP_ENVBUF, sizeof(char *))) == NULL) {
+        log_err("failed to malloc memory for environment\n");
+        exit(123);
+    }
+
+    sprintf(pathbuf, "PATH=%s", AP_SAFE_PATH);
+    cleanenv[cidx] = strdup(pathbuf);
+    if (cleanenv[cidx] == NULL) {
+        log_err("failed to malloc memory for environment\n");
+        exit(124);
+    }
+    cidx++;
+
+    for (ep = envp; *ep && cidx < AP_ENVBUF-1; ep++) {
+        for (idx = 0; safe_env_lst[idx]; idx++) {
+            if (!strncmp(*ep, safe_env_lst[idx],
+                         strlen(safe_env_lst[idx]))) {
+                cleanenv[cidx] = *ep;
+                cidx++;
+                break;
+            }
+        }
+    }
+
+    cleanenv[cidx] = NULL;
+
+    environ = cleanenv;
+}
+
+int main(int argc, char *argv[])
+{
+    int userdir = 0;        /* ~userdir flag             */
+    uid_t uid;              /* user information          */
+    gid_t gid;              /* target group placeholder  */
+    char *target_uname;     /* target user name          */
+    char *target_gname;     /* target group name         */
+    char *target_homedir;   /* target home directory     */
+    char *actual_uname;     /* actual user name          */
+    char *actual_gname;     /* actual group name         */
+    char *cmd;              /* command to be executed    */
+    char cwd[AP_MAXPATH];   /* current working directory */
+    char dwd[AP_MAXPATH];   /* docroot working directory */
+    struct passwd *pw;      /* password entry holder     */
+    struct group *gr;       /* group entry holder        */
+    struct stat dir_info;   /* directory info holder     */
+    struct stat prg_info;   /* program info holder       */
+
+    /*
+     * Start with a "clean" environment
+     */
+    clean_env();
+
+    /*
+     * Check existence/validity of the UID of the user
+     * running this program.  Error out if invalid.
+     */
+    uid = getuid();
+    if ((pw = getpwuid(uid)) == NULL) {
+        log_err("crit: invalid uid: (%lu)\n", (unsigned long)uid);
+        exit(102);
+    }
+    /*
+     * See if this is a 'how were you compiled' request, and
+     * comply if so.
+     */
+    if ((argc > 1)
+        && (! strcmp(argv[1], "-V"))
+        && ((uid == 0)
+#ifdef _OSD_POSIX
+        /* User name comparisons are case insensitive on BS2000/OSD */
+            || (! strcasecmp(AP_HTTPD_USER, pw->pw_name)))
+#else  /* _OSD_POSIX */
+            || (! strcmp(AP_HTTPD_USER, pw->pw_name)))
+#endif /* _OSD_POSIX */
+        ) {
+#ifdef AP_DOC_ROOT
+        fprintf(stderr, " -D AP_DOC_ROOT=\"%s\"\n", AP_DOC_ROOT);
+#endif
+#ifdef AP_GID_MIN
+        fprintf(stderr, " -D AP_GID_MIN=%d\n", AP_GID_MIN);
+#endif
+#ifdef AP_HTTPD_USER
+        fprintf(stderr, " -D AP_HTTPD_USER=\"%s\"\n", AP_HTTPD_USER);
+#endif
+#if defined(AP_LOG_SYSLOG)
+        fprintf(stderr, " -D AP_LOG_SYSLOG\n");
+#elif defined(AP_LOG_EXEC)
+        fprintf(stderr, " -D AP_LOG_EXEC=\"%s\"\n", AP_LOG_EXEC);
+#endif
+#ifdef AP_SAFE_PATH
+        fprintf(stderr, " -D AP_SAFE_PATH=\"%s\"\n", AP_SAFE_PATH);
+#endif
+#ifdef AP_SUEXEC_UMASK
+        fprintf(stderr, " -D AP_SUEXEC_UMASK=%03o\n", AP_SUEXEC_UMASK);
+#endif
+#ifdef AP_UID_MIN
+        fprintf(stderr, " -D AP_UID_MIN=%d\n", AP_UID_MIN);
+#endif
+#ifdef AP_USERDIR_SUFFIX
+        fprintf(stderr, " -D AP_USERDIR_SUFFIX=\"%s\"\n", AP_USERDIR_SUFFIX);
+#endif
+        exit(0);
+    }
+    /*
+     * If there are a proper number of arguments, set
+     * all of them to variables.  Otherwise, error out.
+     */
+    if (argc < 4) {
+        log_err("too few arguments\n");
+        exit(101);
+    }
+    target_uname = argv[1];
+    target_gname = argv[2];
+    cmd = argv[3];
+
+    /*
+     * Check to see if the user running this program
+     * is the user allowed to do so as defined in
+     * suexec.h.  If not the allowed user, error out.
+     */
+#ifdef _OSD_POSIX
+    /* User name comparisons are case insensitive on BS2000/OSD */
+    if (strcasecmp(AP_HTTPD_USER, pw->pw_name)) {
+        log_err("user mismatch (%s instead of %s)\n", pw->pw_name, AP_HTTPD_USER);
+        exit(103);
+    }
+#else  /*_OSD_POSIX*/
+    if (strcmp(AP_HTTPD_USER, pw->pw_name)) {
+        log_err("user mismatch (%s instead of %s)\n", pw->pw_name, AP_HTTPD_USER);
+        exit(103);
+    }
+#endif /*_OSD_POSIX*/
+
+    /*
+     * Check for a leading '/' (absolute path) in the command to be executed,
+     * or attempts to back up out of the current directory,
+     * to protect against attacks.  If any are
+     * found, error out.  Naughty naughty crackers.
+     */
+    if ((cmd[0] == '/') || (!strncmp(cmd, "../", 3))
+        || (strstr(cmd, "/../") != NULL)) {
+        log_err("invalid command (%s)\n", cmd);
+        exit(104);
+    }
+
+    /*
+     * Check to see if this is a ~userdir request.  If
+     * so, set the flag, and remove the '~' from the
+     * target username.
+     */
+    if (!strncmp("~", target_uname, 1)) {
+        target_uname++;
+        userdir = 1;
+    }
+
+    /*
+     * Error out if the target username is invalid.
+     */
+    if (strspn(target_uname, "1234567890") != strlen(target_uname)) {
+        if ((pw = getpwnam(target_uname)) == NULL) {
+            log_err("invalid target user name: (%s)\n", target_uname);
+            exit(105);
+        }
+    }
+    else {
+        if ((pw = getpwuid(atoi(target_uname))) == NULL) {
+            log_err("invalid target user id: (%s)\n", target_uname);
+            exit(121);
+        }
+    }
+
+    /*
+     * Error out if the target group name is invalid.
+     */
+    if (strspn(target_gname, "1234567890") != strlen(target_gname)) {
+        if ((gr = getgrnam(target_gname)) == NULL) {
+            log_err("invalid target group name: (%s)\n", target_gname);
+            exit(106);
+        }
+    }
+    else {
+        if ((gr = getgrgid(atoi(target_gname))) == NULL) {
+            log_err("invalid target group id: (%s)\n", target_gname);
+            exit(106);
+        }
+    }
+    gid = gr->gr_gid;
+    if ((actual_gname = strdup(gr->gr_name)) == NULL) {
+        log_err("failed to alloc memory\n");
+        exit(125);
+    }
+
+#ifdef _OSD_POSIX
+    /*
+     * Initialize BS2000 user environment
+     */
+    {
+        pid_t pid;
+        int status;
+
+        switch (pid = ufork(target_uname)) {
+        case -1:    /* Error */
+            log_err("failed to setup bs2000 environment for user %s: %s\n",
+                    target_uname, strerror(errno));
+            exit(150);
+        case 0:     /* Child */
+            break;
+        default:    /* Father */
+            while (pid != waitpid(pid, &status, 0))
+                ;
+            /* @@@ FIXME: should we deal with STOP signals as well? */
+            if (WIFSIGNALED(status)) {
+                kill (getpid(), WTERMSIG(status));
+            }
+            exit(WEXITSTATUS(status));
+        }
+    }
+#endif /*_OSD_POSIX*/
+
+    /*
+     * Save these for later since initgroups will hose the struct
+     */
+    uid = pw->pw_uid;
+    actual_uname = strdup(pw->pw_name);
+    target_homedir = strdup(pw->pw_dir);
+    if (actual_uname == NULL || target_homedir == NULL) {
+        log_err("failed to alloc memory\n");
+        exit(126);
+    }
+
+    /*
+     * Log the transaction here to be sure we have an open log
+     * before we setuid().
+     */
+    log_no_err("uid: (%s/%s) gid: (%s/%s) cmd: %s\n",
+               target_uname, actual_uname,
+               target_gname, actual_gname,
+               cmd);
+
+    /*
+     * Error out if attempt is made to execute as root or as
+     * a UID less than AP_UID_MIN.  Tsk tsk.
+     */
+    if ((uid == 0) || (uid < AP_UID_MIN)) {
+        log_err("cannot run as forbidden uid (%lu/%s)\n", (unsigned long)uid, cmd);
+        exit(107);
+    }
+
+    /*
+     * Error out if attempt is made to execute as root group
+     * or as a GID less than AP_GID_MIN.  Tsk tsk.
+     */
+    if ((gid == 0) || (gid < AP_GID_MIN)) {
+        log_err("cannot run as forbidden gid (%lu/%s)\n", (unsigned long)gid, cmd);
+        exit(108);
+    }
+
+    /*
+     * Change UID/GID here so that the following tests work over NFS.
+     *
+     * Initialize the group access list for the target user,
+     * and setgid() to the target group. If unsuccessful, error out.
+     */
+    if (((setgid(gid)) != 0) || (initgroups(actual_uname, gid) != 0)) {
+        log_err("failed to setgid (%lu: %s)\n", (unsigned long)gid, cmd);
+        exit(109);
+    }
+
+    /*
+     * setuid() to the target user.  Error out on fail.
+     */
+    if ((setuid(uid)) != 0) {
+        log_err("failed to setuid (%lu: %s)\n", (unsigned long)uid, cmd);
+        exit(110);
+    }
+
+    /*
+     * Get the current working directory, as well as the proper
+     * document root (dependant upon whether or not it is a
+     * ~userdir request).  Error out if we cannot get either one,
+     * or if the current working directory is not in the docroot.
+     * Use chdir()s and getcwd()s to avoid problems with symlinked
+     * directories.  Yuck.
+     */
+    if (getcwd(cwd, AP_MAXPATH) == NULL) {
+        log_err("cannot get current working directory\n");
+        exit(111);
+    }
+
+    if (userdir) {
+        if (((chdir(target_homedir)) != 0) ||
+            ((chdir(AP_USERDIR_SUFFIX)) != 0) ||
+            ((getcwd(dwd, AP_MAXPATH)) == NULL) ||
+            ((chdir(cwd)) != 0)) {
+            log_err("cannot get docroot information (%s)\n", target_homedir);
+            exit(112);
+        }
+    }
+    else {
+        if (((chdir(AP_DOC_ROOT)) != 0) ||
+            ((getcwd(dwd, AP_MAXPATH)) == NULL) ||
+            ((chdir(cwd)) != 0)) {
+            log_err("cannot get docroot information (%s)\n", AP_DOC_ROOT);
+            exit(113);
+        }
+    }
+
+    if ((strncmp(cwd, dwd, strlen(dwd))) != 0) {
+        log_err("command not in docroot (%s/%s)\n", cwd, cmd);
+        exit(114);
+    }
+
+    /*
+     * Stat the cwd and verify it is a directory, or error out.
+     */
+    if (((lstat(cwd, &dir_info)) != 0) || !(S_ISDIR(dir_info.st_mode))) {
+        log_err("cannot stat directory: (%s)\n", cwd);
+        exit(115);
+    }
+
+    /*
+     * Error out if cwd is writable by others.
+     */
+    if ((dir_info.st_mode & S_IWOTH) || (dir_info.st_mode & S_IWGRP)) {
+        log_err("directory is writable by others: (%s)\n", cwd);
+        exit(116);
+    }
+
+    /*
+     * Error out if we cannot stat the program.
+     */
+    if (((lstat(cmd, &prg_info)) != 0) || (S_ISLNK(prg_info.st_mode))) {
+        log_err("cannot stat program: (%s)\n", cmd);
+        exit(117);
+    }
+
+    /*
+     * Error out if the program is writable by others.
+     */
+    if ((prg_info.st_mode & S_IWOTH) || (prg_info.st_mode & S_IWGRP)) {
+        log_err("file is writable by others: (%s/%s)\n", cwd, cmd);
+        exit(118);
+    }
+
+    /*
+     * Error out if the file is setuid or setgid.
+     */
+    if ((prg_info.st_mode & S_ISUID) || (prg_info.st_mode & S_ISGID)) {
+        log_err("file is either setuid or setgid: (%s/%s)\n", cwd, cmd);
+        exit(119);
+    }
+
+    /*
+     * Error out if the target name/group is different from
+     * the name/group of the cwd or the program.
+     */
+    if ((uid != dir_info.st_uid) ||
+        (gid != dir_info.st_gid) ||
+        (uid != prg_info.st_uid) ||
+        (gid != prg_info.st_gid)) {
+        log_err("target uid/gid (%lu/%lu) mismatch "
+                "with directory (%lu/%lu) or program (%lu/%lu)\n",
+                (unsigned long)uid, (unsigned long)gid,
+                (unsigned long)dir_info.st_uid, (unsigned long)dir_info.st_gid,
+                (unsigned long)prg_info.st_uid, (unsigned long)prg_info.st_gid);
+        exit(120);
+    }
+    /*
+     * Error out if the program is not executable for the user.
+     * Otherwise, she won't find any error in the logs except for
+     * "[error] Premature end of script headers: ..."
+     */
+    if (!(prg_info.st_mode & S_IXUSR)) {
+        log_err("file has no execute permission: (%s/%s)\n", cwd, cmd);
+        exit(121);
+    }
+
+#ifdef AP_SUEXEC_UMASK
+    /*
+     * umask() uses inverse logic; bits are CLEAR for allowed access.
+     */
+    if ((~AP_SUEXEC_UMASK) & 0022) {
+        log_err("notice: AP_SUEXEC_UMASK of %03o allows "
+                "write permission to group and/or other\n", AP_SUEXEC_UMASK);
+    }
+    umask(AP_SUEXEC_UMASK);
+#endif /* AP_SUEXEC_UMASK */
+
+    /* Be sure to close the log file so the CGI can't mess with it. */
+#ifdef AP_LOG_SYSLOG
+    if (log_open) {
+        closelog();
+        log_open = 0;
+    }
+#else
+    if (log != NULL) {
+#if APR_HAVE_FCNTL_H
+        /*
+         * ask fcntl(2) to set the FD_CLOEXEC flag on the log file,
+         * so it'll be automagically closed if the exec() call succeeds.
+         */
+        fflush(log);
+        setbuf(log, NULL);
+        if ((fcntl(fileno(log), F_SETFD, FD_CLOEXEC) == -1)) {
+            log_err("error: can't set close-on-exec flag");
+            exit(122);
+        }
+#else
+        /*
+         * In this case, exec() errors won't be logged because we have already
+         * dropped privileges and won't be able to reopen the log file.
+         */
+        fclose(log);
+        log = NULL;
+#endif
+    }
+#endif
+
+    /*
+     * Execute the command, replacing our image with its own.
+     */
+#ifdef NEED_HASHBANG_EMUL
+    /* We need the #! emulation when we want to execute scripts */
+    {
+        extern char **environ;
+
+        ap_execve(cmd, &argv[3], environ);
+    }
+#else /*NEED_HASHBANG_EMUL*/
+    execv(cmd, &argv[3]);
+#endif /*NEED_HASHBANG_EMUL*/
+
+    /*
+     * (I can't help myself...sorry.)
+     *
+     * Uh oh.  Still here.  Where's the kaboom?  There was supposed to be an
+     * EARTH-shattering kaboom!
+     *
+     * Oh well, log the failure and error out.
+     */
+    log_err("(%d)%s: exec failed (%s)\n", errno, strerror(errno), cmd);
+    exit(255);
+}