src/lxc/attach_options.h

   1 /*! \file
   2  *
   3  * lxc: linux Container library
   4  *
   5  * (C) Copyright IBM Corp. 2007, 2008
   6  *
   7  * Authors:
   8  * Daniel Lezcano <daniel.lezcano at free.fr>
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 #ifndef __LXC_ATTACH_OPTIONS_H
  26 #define __LXC_ATTACH_OPTIONS_H
  27
  28 #include <sys/types.h>
  29
  30 #ifdef  __cplusplus
  31 extern "C" {
  32 #endif
  33
  34 /*!
  35  * LXC environment policy.
  36  */
  37 typedef enum lxc_attach_env_policy_t {
  38         LXC_ATTACH_KEEP_ENV,   //!< Retain the environment
  39         LXC_ATTACH_CLEAR_ENV   //!< Clear the environment
  40 } lxc_attach_env_policy_t;
  41
  42 enum {
  43         /* the following are on by default: */
  44         LXC_ATTACH_MOVE_TO_CGROUP        = 0x00000001, //!< Move to cgroup
  45         LXC_ATTACH_DROP_CAPABILITIES     = 0x00000002, //!< Drop capabilities
  46         LXC_ATTACH_SET_PERSONALITY       = 0x00000004, //!< Set personality
  47         LXC_ATTACH_LSM_EXEC              = 0x00000008, //!< Execute under a Linux Security Module
  48
  49         /* the following are off by default */
  50         LXC_ATTACH_REMOUNT_PROC_SYS      = 0x00010000, //!< Remount /proc filesystem
  51         LXC_ATTACH_LSM_NOW               = 0x00020000, //!< FIXME: unknown
  52
  53         /* we have 16 bits for things that are on by default
  54          * and 16 bits that are off by default, that should
  55          * be sufficient to keep binary compatibility for
  56          * a while
  57          */
  58         LXC_ATTACH_DEFAULT               = 0x0000FFFF  //!< Mask of flags to apply by default
  59 };
  60
  61 /*! All Linux Security Module flags */
  62 #define LXC_ATTACH_LSM (LXC_ATTACH_LSM_EXEC | LXC_ATTACH_LSM_NOW)
  63
  64 /*! LXC attach function type.
  65  *
  66  * Function to run in container.
  67  *
  68  * \param payload \ref lxc_attach_command_t to run.
  69  *
  70  * \return Function should return \c 0 on success, and any other value to denote failure.
  71  */
  72 typedef int (*lxc_attach_exec_t)(void* payload);
  73
  74 /*!
  75  * LXC attach options for \ref lxc_container \c attach().
  76  */
  77 typedef struct lxc_attach_options_t {
  78         /*! Any combination of LXC_ATTACH_* flags */
  79         int attach_flags;
  80
  81         /*! The namespaces to attach to (CLONE_NEW... flags) */
  82         int namespaces;
  83
  84         /*! Initial personality (\c -1 to autodetect).
  85          * \warning This may be ignored if lxc is compiled without personality support)
  86          */
  87         long personality;
  88
  89         /*! Inital current directory, use \c NULL to use cwd.
  90          * If the current directory does not exist in the container, the
  91          * root directory will be used instead because of kernel defaults.
  92          */
  93         char* initial_cwd;
  94
  95         /*! The user-id to run as.
  96          *
  97          * \note Set to \c -1 for default behaviour (init uid for userns
  98          * containers or \c 0 (super-user) if detection fails).
  99          */
 100         uid_t uid;
 101
 102         /*! The group-id to run as.
 103          *
 104          * \note Set to \c -1 for default behaviour (init gid for userns
 105          * containers or \c 0 (super-user) if detection fails).
 106          */
 107         gid_t gid;
 108
 109         /*! Environment policy */
 110         lxc_attach_env_policy_t env_policy;
 111
 112         /*! Extra environment variables to set in the container environment */
 113         char** extra_env_vars;
 114
 115         /*! Names of environment variables in existing environment to retain
 116          * in container environment.
 117          */
 118         char** extra_keep_env;
 119
 120         /**@{*/
 121         /*! File descriptors for stdin, stdout and stderr,
 122          * \c dup2() will be used before calling exec_function,
 123          * (assuming not \c 0, \c 1 and \c 2 are specified) and the
 124          * original fds are closed before passing control
 125          * over. Any \c O_CLOEXEC flag will be removed after
 126          * that.
 127          */
 128         int stdin_fd; /*!< stdin file descriptor */
 129         int stdout_fd; /*!< stdout file descriptor */
 130         int stderr_fd; /*!< stderr file descriptor */
 131         /**@}*/
 132 } lxc_attach_options_t;
 133
 134 /*! Default attach options to use */
 135 #define LXC_ATTACH_OPTIONS_DEFAULT \
 136         { \
 137                 /* .attach_flags = */   LXC_ATTACH_DEFAULT, \
 138                 /* .namespaces = */     -1, \
 139                 /* .personality = */    -1, \
 140                 /* .initial_cwd = */    NULL, \
 141                 /* .uid = */            (uid_t)-1, \
 142                 /* .gid = */            (gid_t)-1, \
 143                 /* .env_policy = */     LXC_ATTACH_KEEP_ENV, \
 144                 /* .extra_env_vars = */ NULL, \
 145                 /* .extra_keep_env = */ NULL, \
 146                 /* .stdin_fd = */       0, 1, 2 \
 147         }
 148
 149 /*!
 150  * Representation of a command to run in a container.
 151  */
 152 typedef struct lxc_attach_command_t {
 153         char* program; /*!< The program to run (passed to execvp) */
 154         char** argv;   /*!< The argv pointer of that program, including the program itself in argv[0] */
 155 } lxc_attach_command_t;
 156
 157 /*!
 158  * \brief Run a command in the container.
 159  *
 160  * \param payload \ref lxc_attach_command_t to run.
 161  *
 162  * \return \c -1 on error, exit code of lxc_attach_command_t program on success.
 163  */
 164 extern int lxc_attach_run_command(void* payload);
 165
 166 /*!
 167  * \brief Run a shell command in the container.
 168  *
 169  * \param payload Not used.
 170  *
 171  * \return Exit code of shell.
 172  */
 173 extern int lxc_attach_run_shell(void* payload);
 174
 175 #ifdef  __cplusplus
 176 }
 177 #endif
 178
 179 #endif