diff options
Diffstat (limited to 'include/uapi/linux/landlock.h')
| -rw-r--r-- | include/uapi/linux/landlock.h | 164 |
1 files changed, 132 insertions, 32 deletions
diff --git a/include/uapi/linux/landlock.h b/include/uapi/linux/landlock.h index 33745642f787..10a346e55e95 100644 --- a/include/uapi/linux/landlock.h +++ b/include/uapi/linux/landlock.h @@ -4,6 +4,7 @@ * * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net> * Copyright © 2018-2020 ANSSI + * Copyright © 2021-2025 Microsoft Corporation */ #ifndef _UAPI_LINUX_LANDLOCK_H @@ -52,14 +53,90 @@ struct landlock_ruleset_attr { __u64 scoped; }; -/* - * sys_landlock_create_ruleset() flags: +/** + * DOC: landlock_create_ruleset_flags + * + * **Flags** + * + * %LANDLOCK_CREATE_RULESET_VERSION + * Get the highest supported Landlock ABI version (starting at 1). * - * - %LANDLOCK_CREATE_RULESET_VERSION: Get the highest supported Landlock ABI - * version. + * %LANDLOCK_CREATE_RULESET_ERRATA + * Get a bitmask of fixed issues for the current Landlock ABI version. */ /* clang-format off */ #define LANDLOCK_CREATE_RULESET_VERSION (1U << 0) +#define LANDLOCK_CREATE_RULESET_ERRATA (1U << 1) +/* clang-format on */ + +/** + * DOC: landlock_restrict_self_flags + * + * **Flags** + * + * By default, denied accesses originating from programs that sandbox themselves + * are logged via the audit subsystem. Such events typically indicate unexpected + * behavior, such as bugs or exploitation attempts. However, to avoid excessive + * logging, access requests denied by a domain not created by the originating + * program are not logged by default. The rationale is that programs should know + * their own behavior, but not necessarily the behavior of other programs. This + * default configuration is suitable for most programs that sandbox themselves. + * For specific use cases, the following flags allow programs to modify this + * default logging behavior. + * + * The %LANDLOCK_RESTRICT_SELF_LOG_SAME_EXEC_OFF and + * %LANDLOCK_RESTRICT_SELF_LOG_NEW_EXEC_ON flags apply to the newly created + * Landlock domain. + * + * %LANDLOCK_RESTRICT_SELF_LOG_SAME_EXEC_OFF + * Disables logging of denied accesses originating from the thread creating + * the Landlock domain, as well as its children, as long as they continue + * running the same executable code (i.e., without an intervening + * :manpage:`execve(2)` call). This is intended for programs that execute + * unknown code without invoking :manpage:`execve(2)`, such as script + * interpreters. Programs that only sandbox themselves should not set this + * flag, so users can be notified of unauthorized access attempts via system + * logs. + * + * %LANDLOCK_RESTRICT_SELF_LOG_NEW_EXEC_ON + * Enables logging of denied accesses after an :manpage:`execve(2)` call, + * providing visibility into unauthorized access attempts by newly executed + * programs within the created Landlock domain. This flag is recommended + * only when all potential executables in the domain are expected to comply + * with the access restrictions, as excessive audit log entries could make + * it more difficult to identify critical events. + * + * %LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF + * Disables logging of denied accesses originating from nested Landlock + * domains created by the caller or its descendants. This flag should be set + * according to runtime configuration, not hardcoded, to avoid suppressing + * important security events. It is useful for container runtimes or + * sandboxing tools that may launch programs which themselves create + * Landlock domains and could otherwise generate excessive logs. Unlike + * ``LANDLOCK_RESTRICT_SELF_LOG_SAME_EXEC_OFF``, this flag only affects + * future nested domains, not the one being created. It can also be used + * with a @ruleset_fd value of -1 to mute subdomain logs without creating a + * domain. When combined with %LANDLOCK_RESTRICT_SELF_TSYNC and a + * @ruleset_fd value of -1, this configuration is propagated to all threads + * of the current process. + * + * The following flag supports policy enforcement in multithreaded processes: + * + * %LANDLOCK_RESTRICT_SELF_TSYNC + * Applies the new Landlock configuration atomically to all threads of the + * current process, including the Landlock domain and logging + * configuration. This overrides the Landlock configuration of sibling + * threads, irrespective of previously established Landlock domains and + * logging configurations on these threads. + * + * If the calling thread is running with no_new_privs, this operation + * enables no_new_privs on the sibling threads as well. + */ +/* clang-format off */ +#define LANDLOCK_RESTRICT_SELF_LOG_SAME_EXEC_OFF (1U << 0) +#define LANDLOCK_RESTRICT_SELF_LOG_NEW_EXEC_ON (1U << 1) +#define LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF (1U << 2) +#define LANDLOCK_RESTRICT_SELF_TSYNC (1U << 3) /* clang-format on */ /** @@ -120,11 +197,13 @@ struct landlock_net_port_attr { * It should be noted that port 0 passed to :manpage:`bind(2)` will bind * to an available port from the ephemeral port range. This can be * configured with the ``/proc/sys/net/ipv4/ip_local_port_range`` sysctl - * (also used for IPv6). + * (also used for IPv6), and within that range, on a per-socket basis + * with ``setsockopt(IP_LOCAL_PORT_RANGE)``. * - * A Landlock rule with port 0 and the ``LANDLOCK_ACCESS_NET_BIND_TCP`` + * A Landlock rule with port 0 and the %LANDLOCK_ACCESS_NET_BIND_TCP * right means that requesting to bind on port 0 is allowed and it will - * automatically translate to binding on the related port range. + * automatically translate to binding on a kernel-assigned ephemeral + * port. */ __u64 port; }; @@ -154,6 +233,43 @@ struct landlock_net_port_attr { * :manpage:`ftruncate(2)`, :manpage:`creat(2)`, or :manpage:`open(2)` with * ``O_TRUNC``. This access right is available since the third version of the * Landlock ABI. + * - %LANDLOCK_ACCESS_FS_IOCTL_DEV: Invoke :manpage:`ioctl(2)` commands on an opened + * character or block device. + * + * This access right applies to all `ioctl(2)` commands implemented by device + * drivers. However, the following common IOCTL commands continue to be + * invokable independent of the %LANDLOCK_ACCESS_FS_IOCTL_DEV right: + * + * * IOCTL commands targeting file descriptors (``FIOCLEX``, ``FIONCLEX``), + * * IOCTL commands targeting file descriptions (``FIONBIO``, ``FIOASYNC``), + * * IOCTL commands targeting file systems (``FIFREEZE``, ``FITHAW``, + * ``FIGETBSZ``, ``FS_IOC_GETFSUUID``, ``FS_IOC_GETFSSYSFSPATH``) + * * Some IOCTL commands which do not make sense when used with devices, but + * whose implementations are safe and return the right error codes + * (``FS_IOC_FIEMAP``, ``FICLONE``, ``FICLONERANGE``, ``FIDEDUPERANGE``) + * + * This access right is available since the fifth version of the Landlock + * ABI. + * - %LANDLOCK_ACCESS_FS_RESOLVE_UNIX: Look up pathname UNIX domain sockets + * (:manpage:`unix(7)`). On UNIX domain sockets, this restricts both calls to + * :manpage:`connect(2)` as well as calls to :manpage:`sendmsg(2)` with an + * explicit recipient address. + * + * This access right only applies to connections to UNIX server sockets which + * were created outside of the newly created Landlock domain (e.g. from within + * a parent domain or from an unrestricted process). Newly created UNIX + * servers within the same Landlock domain continue to be accessible. In this + * regard, %LANDLOCK_ACCESS_FS_RESOLVE_UNIX has the same semantics as the + * ``LANDLOCK_SCOPE_*`` flags. + * + * If a resolve attempt is denied, the operation returns an ``EACCES`` error, + * in line with other filesystem access rights (but different to denials for + * abstract UNIX domain sockets). + * + * This access right is available since the ninth version of the Landlock ABI. + * + * The rationale for this design is described in + * :ref:`Documentation/security/landlock.rst <scoped-flags-interaction>`. * * Whether an opened file can be truncated with :manpage:`ftruncate(2)` or used * with `ioctl(2)` is determined during :manpage:`open(2)`, in the same way as @@ -213,26 +329,6 @@ struct landlock_net_port_attr { * If multiple requirements are not met, the ``EACCES`` error code takes * precedence over ``EXDEV``. * - * The following access right applies both to files and directories: - * - * - %LANDLOCK_ACCESS_FS_IOCTL_DEV: Invoke :manpage:`ioctl(2)` commands on an opened - * character or block device. - * - * This access right applies to all `ioctl(2)` commands implemented by device - * drivers. However, the following common IOCTL commands continue to be - * invokable independent of the %LANDLOCK_ACCESS_FS_IOCTL_DEV right: - * - * * IOCTL commands targeting file descriptors (``FIOCLEX``, ``FIONCLEX``), - * * IOCTL commands targeting file descriptions (``FIONBIO``, ``FIOASYNC``), - * * IOCTL commands targeting file systems (``FIFREEZE``, ``FITHAW``, - * ``FIGETBSZ``, ``FS_IOC_GETFSUUID``, ``FS_IOC_GETFSSYSFSPATH``) - * * Some IOCTL commands which do not make sense when used with devices, but - * whose implementations are safe and return the right error codes - * (``FS_IOC_FIEMAP``, ``FICLONE``, ``FICLONERANGE``, ``FIDEDUPERANGE``) - * - * This access right is available since the fifth version of the Landlock - * ABI. - * * .. warning:: * * It is currently not possible to restrict some file-related actions @@ -259,6 +355,7 @@ struct landlock_net_port_attr { #define LANDLOCK_ACCESS_FS_REFER (1ULL << 13) #define LANDLOCK_ACCESS_FS_TRUNCATE (1ULL << 14) #define LANDLOCK_ACCESS_FS_IOCTL_DEV (1ULL << 15) +#define LANDLOCK_ACCESS_FS_RESOLVE_UNIX (1ULL << 16) /* clang-format on */ /** @@ -268,13 +365,14 @@ struct landlock_net_port_attr { * ~~~~~~~~~~~~~~~~ * * These flags enable to restrict a sandboxed process to a set of network - * actions. This is supported since the Landlock ABI version 4. + * actions. * * The following access rights apply to TCP port numbers: * - * - %LANDLOCK_ACCESS_NET_BIND_TCP: Bind a TCP socket to a local port. - * - %LANDLOCK_ACCESS_NET_CONNECT_TCP: Connect an active TCP socket to - * a remote port. + * - %LANDLOCK_ACCESS_NET_BIND_TCP: Bind TCP sockets to the given local + * port. Support added in Landlock ABI version 4. + * - %LANDLOCK_ACCESS_NET_CONNECT_TCP: Connect TCP sockets to the given + * remote port. Support added in Landlock ABI version 4. */ /* clang-format off */ #define LANDLOCK_ACCESS_NET_BIND_TCP (1ULL << 0) @@ -291,11 +389,13 @@ struct landlock_net_port_attr { * Setting a flag for a ruleset will isolate the Landlock domain to forbid * connections to resources outside the domain. * + * This is supported since Landlock ABI version 6. + * * Scopes: * * - %LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET: Restrict a sandboxed process from * connecting to an abstract UNIX socket created by a process outside the - * related Landlock domain (e.g. a parent domain or a non-sandboxed process). + * related Landlock domain (e.g., a parent domain or a non-sandboxed process). * - %LANDLOCK_SCOPE_SIGNAL: Restrict a sandboxed process from sending a signal * to another process outside the domain. */ |