| .. | .. |
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| 15 | 15 | #define SECCOMP_SET_MODE_STRICT 0 |
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| 16 | 16 | #define SECCOMP_SET_MODE_FILTER 1 |
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| 17 | 17 | #define SECCOMP_GET_ACTION_AVAIL 2 |
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| 18 | +#define SECCOMP_GET_NOTIF_SIZES 3 |
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| 18 | 19 | |
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| 19 | 20 | /* Valid flags for SECCOMP_SET_MODE_FILTER */ |
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| 20 | | -#define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0) |
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| 21 | | -#define SECCOMP_FILTER_FLAG_LOG (1UL << 1) |
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| 22 | | -#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2) |
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| 21 | +#define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0) |
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| 22 | +#define SECCOMP_FILTER_FLAG_LOG (1UL << 1) |
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| 23 | +#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2) |
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| 24 | +#define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3) |
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| 25 | +#define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4) |
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| 23 | 26 | |
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| 24 | 27 | /* |
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| 25 | 28 | * All BPF programs must return a 32-bit value. |
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| .. | .. |
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| 35 | 38 | #define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD |
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| 36 | 39 | #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */ |
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| 37 | 40 | #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */ |
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| 41 | +#define SECCOMP_RET_USER_NOTIF 0x7fc00000U /* notifies userspace */ |
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| 38 | 42 | #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */ |
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| 39 | 43 | #define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */ |
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| 40 | 44 | #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */ |
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| .. | .. |
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| 60 | 64 | __u64 args[6]; |
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| 61 | 65 | }; |
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| 62 | 66 | |
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| 67 | +struct seccomp_notif_sizes { |
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| 68 | + __u16 seccomp_notif; |
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| 69 | + __u16 seccomp_notif_resp; |
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| 70 | + __u16 seccomp_data; |
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| 71 | +}; |
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| 72 | + |
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| 73 | +struct seccomp_notif { |
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| 74 | + __u64 id; |
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| 75 | + __u32 pid; |
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| 76 | + __u32 flags; |
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| 77 | + struct seccomp_data data; |
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| 78 | +}; |
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| 79 | + |
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| 80 | +/* |
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| 81 | + * Valid flags for struct seccomp_notif_resp |
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| 82 | + * |
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| 83 | + * Note, the SECCOMP_USER_NOTIF_FLAG_CONTINUE flag must be used with caution! |
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| 84 | + * If set by the process supervising the syscalls of another process the |
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| 85 | + * syscall will continue. This is problematic because of an inherent TOCTOU. |
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| 86 | + * An attacker can exploit the time while the supervised process is waiting on |
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| 87 | + * a response from the supervising process to rewrite syscall arguments which |
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| 88 | + * are passed as pointers of the intercepted syscall. |
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| 89 | + * It should be absolutely clear that this means that the seccomp notifier |
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| 90 | + * _cannot_ be used to implement a security policy! It should only ever be used |
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| 91 | + * in scenarios where a more privileged process supervises the syscalls of a |
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| 92 | + * lesser privileged process to get around kernel-enforced security |
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| 93 | + * restrictions when the privileged process deems this safe. In other words, |
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| 94 | + * in order to continue a syscall the supervising process should be sure that |
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| 95 | + * another security mechanism or the kernel itself will sufficiently block |
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| 96 | + * syscalls if arguments are rewritten to something unsafe. |
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| 97 | + * |
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| 98 | + * Similar precautions should be applied when stacking SECCOMP_RET_USER_NOTIF |
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| 99 | + * or SECCOMP_RET_TRACE. For SECCOMP_RET_USER_NOTIF filters acting on the |
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| 100 | + * same syscall, the most recently added filter takes precedence. This means |
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| 101 | + * that the new SECCOMP_RET_USER_NOTIF filter can override any |
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| 102 | + * SECCOMP_IOCTL_NOTIF_SEND from earlier filters, essentially allowing all |
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| 103 | + * such filtered syscalls to be executed by sending the response |
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| 104 | + * SECCOMP_USER_NOTIF_FLAG_CONTINUE. Note that SECCOMP_RET_TRACE can equally |
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| 105 | + * be overriden by SECCOMP_USER_NOTIF_FLAG_CONTINUE. |
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| 106 | + */ |
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| 107 | +#define SECCOMP_USER_NOTIF_FLAG_CONTINUE (1UL << 0) |
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| 108 | + |
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| 109 | +struct seccomp_notif_resp { |
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| 110 | + __u64 id; |
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| 111 | + __s64 val; |
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| 112 | + __s32 error; |
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| 113 | + __u32 flags; |
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| 114 | +}; |
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| 115 | + |
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| 116 | +/* valid flags for seccomp_notif_addfd */ |
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| 117 | +#define SECCOMP_ADDFD_FLAG_SETFD (1UL << 0) /* Specify remote fd */ |
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| 118 | + |
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| 119 | +/** |
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| 120 | + * struct seccomp_notif_addfd |
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| 121 | + * @id: The ID of the seccomp notification |
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| 122 | + * @flags: SECCOMP_ADDFD_FLAG_* |
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| 123 | + * @srcfd: The local fd number |
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| 124 | + * @newfd: Optional remote FD number if SETFD option is set, otherwise 0. |
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| 125 | + * @newfd_flags: The O_* flags the remote FD should have applied |
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| 126 | + */ |
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| 127 | +struct seccomp_notif_addfd { |
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| 128 | + __u64 id; |
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| 129 | + __u32 flags; |
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| 130 | + __u32 srcfd; |
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| 131 | + __u32 newfd; |
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| 132 | + __u32 newfd_flags; |
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| 133 | +}; |
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| 134 | + |
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| 135 | +#define SECCOMP_IOC_MAGIC '!' |
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| 136 | +#define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr) |
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| 137 | +#define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type) |
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| 138 | +#define SECCOMP_IOW(nr, type) _IOW(SECCOMP_IOC_MAGIC, nr, type) |
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| 139 | +#define SECCOMP_IOWR(nr, type) _IOWR(SECCOMP_IOC_MAGIC, nr, type) |
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| 140 | + |
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| 141 | +/* Flags for seccomp notification fd ioctl. */ |
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| 142 | +#define SECCOMP_IOCTL_NOTIF_RECV SECCOMP_IOWR(0, struct seccomp_notif) |
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| 143 | +#define SECCOMP_IOCTL_NOTIF_SEND SECCOMP_IOWR(1, \ |
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| 144 | + struct seccomp_notif_resp) |
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| 145 | +#define SECCOMP_IOCTL_NOTIF_ID_VALID SECCOMP_IOW(2, __u64) |
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| 146 | +/* On success, the return value is the remote process's added fd number */ |
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| 147 | +#define SECCOMP_IOCTL_NOTIF_ADDFD SECCOMP_IOW(3, \ |
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| 148 | + struct seccomp_notif_addfd) |
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| 149 | + |
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| 63 | 150 | #endif /* _UAPI_LINUX_SECCOMP_H */ |
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