VERIEXEC(4)

VERIEXEC(4) | NetBSD Kernel Interfaces Manual | VERIEXEC(4)

# NAME

veriexec — Veriexec pseudo-device

# SYNOPSIS

pseudo-device veriexec

# DESCRIPTION

Veriexec verifies the integrity of specified executables and files before they are run or read. This makes it much more difficult to insert a trojan horse into the system and also makes it more difficult to run binaries that are not supposed to be running, for example, packet sniffers, DDoS clients and so on.

The veriexec pseudo-device is used to load and delete entries to and from the in-kernel Veriexec databases, as well as query information about them. It can also be used to dump the entire database.

## Kernel-userland interaction

Veriexec uses proplib(3) for communication between the kernel and userland.

VERIEXEC_LOAD
  Load an entry for a file to be monitored by Veriexec.

  The dictionary passed contains the following elements:

  Name | Type | Purpose
  file | string | filename for this entry
  entry-type | uint8 | entry type (see below)
  fp-type | string | fingerprint hashing algorithm
  fp | data | the fingerprint

  “entry-type” can be one or more (binary-OR'd) of the following:

  Type | Effect
  VERIEXEC_DIRECT | can execute directly
  VERIEXEC_INDIRECT | can execute indirectly (interpreter, mmap(2))
  VERIEXEC_FILE | can be opened
  VERIEXEC_UNTRUSTED | located on untrusted storage

VERIEXEC_DELETE
  Removes either an entry for a single file or entries for an entire mount from Veriexec.

  The dictionary passed contains the following elements:

  Name | Type | Purpose
  file | string | filename or mount-point

VERIEXEC_DUMP
  Dump the Veriexec monitored files database from the kernel.

  Only files that the filename is kept for them will be dumped. The returned array contains dictionaries with the following elements:

  Name | Type | Purpose
  file | string | filename
  fp-type | string | fingerprint hashing algorithm
  fp | data | the fingerprint
  entry-type | uint8 | entry type (see above)

VERIEXEC_FLUSH
  Flush the Veriexec database, removing all entries.

  This command has no parameters.

VERIEXEC_QUERY
  Queries Veriexec about a file, returning information that may be useful about it.

  The dictionary passed contains the following elements:

  Name | Type | Purpose
  file | string | filename

  The dictionary returned contains the following elements:

  Name | Type | Purpose
  entry-type | uint8 | entry type (see above)
  status | uint8 | entry status
  fp-type | string | fingerprint hashing algorithm
  fp | data | the fingerprint

  “status” can be one of the following:

  Status | Meaning
  FINGERPRINT_NOTEVAL | not evaluated
  FINGERPRINT_VALID | fingerprint match
  FINGERPRINT_MISMATCH | fingerprint mismatch

Note that the requests VERIEXEC_LOAD, VERIEXEC_DELETE, and VERIEXEC_FLUSH are not permitted once the strict level has been raised past 0.

# SEE ALSO

proplib(3), sysctl(3), security(7), sysctl(8), veriexecctl(8), veriexecgen(8), veriexec(9)

# NOTES

veriexec is part of the default configuration on the following architectures: amd64, i386, prep, sparc64.

# AUTHORS

Brett Lymn <blymn@NetBSD.org> Elad Efrat <elad@NetBSD.org>

March 19, 2011 | NetBSD 5.99