libseccomp/doc/man/man3/seccomp_arch_add.3

   1 .TH "seccomp_arch_add" 3 "7 May 2014" "paul@paul-moore.com" "libseccomp Documentation"
   2 .\" //////////////////////////////////////////////////////////////////////////
   3 .SH NAME
   4 .\" //////////////////////////////////////////////////////////////////////////
   5 seccomp_arch_add, seccomp_arch_remove, seccomp_arch_exist, seccomp_arch_native \- Manage seccomp filter architectures
   6 .\" //////////////////////////////////////////////////////////////////////////
   7 .SH SYNOPSIS
   8 .\" //////////////////////////////////////////////////////////////////////////
   9 .nf
  10 .B #include <seccomp.h>
  11 .sp
  12 .B typedef void * scmp_filter_ctx;
  13 .sp
  14 .B #define SCMP_ARCH_NATIVE
  15 .B #define SCMP_ARCH_X86
  16 .B #define SCMP_ARCH_X86_64
  17 .sp
  18 .BI "uint32_t seccomp_arch_resolve_name(const char *" arch_name ");"
  19 .BI "uint32_t seccomp_arch_native();"
  20 .BI "int seccomp_arch_exist(const scmp_filter_ctx " ctx ", uint32_t " arch_token ");"
  21 .BI "int seccomp_arch_add(scmp_filter_ctx " ctx ", uint32_t " arch_token ");"
  22 .BI "int seccomp_arch_remove(scmp_filter_ctx " ctx ", uint32_t " arch_token ");"
  23 .sp
  24 Link with \fI\-lseccomp\fP.
  25 .fi
  26 .\" //////////////////////////////////////////////////////////////////////////
  27 .SH DESCRIPTION
  28 .\" //////////////////////////////////////////////////////////////////////////
  29 .P
  30 The
  31 .BR seccomp_arch_exist ()
  32 function tests to see if a given architecture has been added to the seccomp
  33 filter in
  34 .I ctx
  35 , where the
  36 .BR seccomp_arch_add ()
  37 and
  38 .BR seccomp_arch_remove ()
  39 add and remove, respectively, architectures from the seccomp filter.  In all
  40 three functions, the architecture values given in
  41 .I arch_token
  42 should be the
  43 .BR SCMP_ARCH_*
  44 defined constants; with the
  45 .BR SCMP_ARCH_NATIVE
  46 constant always referring to the native compiled architecture.  The
  47 .BR seccomp_arch_native ()
  48 function returns the system's architecture such that it will match one of the
  49 .BR SCMP_ARCH_*
  50 constants.  While the
  51 .BR seccomp_arch_resolve_name ()
  52 function also returns a
  53 .BR SCMP_ARCH_*
  54 constant, the returned token matches the name of the architecture
  55 passed as an argument to the function.
  56 .P
  57 When a seccomp filter is initialized with the call to
  58 .BR seccomp_init (3)
  59 the native architecture is automatically added to the filter.
  60 .P
  61 While it is possible to remove all architectures from a filter, most of the
  62 libseccomp APIs will fail if the filter does not contain at least one
  63 architecture.
  64 .P
  65 When adding a new architecture to an existing filter, the existing rules will
  66 not be added to the new architecture.  However, rules added after adding the
  67 new architecture will be added to all of the architectures in the filter.
  68 .\" //////////////////////////////////////////////////////////////////////////
  69 .SH RETURN VALUE
  70 .\" //////////////////////////////////////////////////////////////////////////
  71 The
  72 .BR seccomp_arch_add ()
  73 and
  74 .BR seccomp_arch_remove ()
  75 functions return zero on success, negative errno values on failure.  The
  76 .BR seccomp_arch_exist ()
  77 function returns zero if the architecture exists, \-EEXIST if it does not, and
  78 other negative errno values on failure.
  79 .\" //////////////////////////////////////////////////////////////////////////
  80 .SH EXAMPLES
  81 .\" //////////////////////////////////////////////////////////////////////////
  82 .nf
  83 #include <seccomp.h>
  84
  85 int main(int argc, char *argv[])
  86 {
  87         int rc = \-1;
  88         scmp_filter_ctx ctx;
  89
  90         ctx = seccomp_init(SCMP_ACT_KILL);
  91         if (ctx == NULL)
  92                 goto out;
  93
  94         if (seccomp_arch_exist(ctx, SCMP_ARCH_X86) == \-EEXIST) {
  95                 rc = seccomp_arch_add(ctx, SCMP_ARCH_X86);
  96                 if (rc != 0)
  97                         goto out_all;
  98                 rc = seccomp_arch_remove(ctx, SCMP_ARCH_NATIVE);
  99                 if (rc != 0)
 100                         goto out_all;
 101         }
 102
 103         /* ... */
 104
 105 out:
 106         seccomp_release(ctx);
 107         return \-rc;
 108 }
 109 .fi
 110 .\" //////////////////////////////////////////////////////////////////////////
 111 .SH NOTES
 112 .\" //////////////////////////////////////////////////////////////////////////
 113 .P
 114 While the seccomp filter can be generated independent of the kernel, kernel
 115 support is required to load and enforce the seccomp filter generated by
 116 libseccomp.
 117 .P
 118 The libseccomp project site, with more information and the source code
 119 repository, can be found at https://github.com/seccomp/libseccomp.  This tool,
 120 as well as the libseccomp library, is currently under development, please
 121 report any bugs at the project site or directly to the author.
 122 .\" //////////////////////////////////////////////////////////////////////////
 123 .SH AUTHOR
 124 .\" //////////////////////////////////////////////////////////////////////////
 125 Paul Moore <paul@paul-moore.com>
 126 .\" //////////////////////////////////////////////////////////////////////////
 127 .SH SEE ALSO
 128 .\" //////////////////////////////////////////////////////////////////////////
 129 .BR seccomp_init (3),
 130 .BR seccomp_reset (3),
 131 .BR seccom_merge (3)