Clarify that user code is required to allocate sufficient space for the
addressing scheme in use in the call to DTLSv1_listen.
Reviewed-by: Andy Polyakov <appro@openssl.org>
This commit adds documentation for the new -listen option to s_server. Along
the way it also adds documentation for -dtls, -dtls1 and -dtls1_2 which was
missing.
Reviewed-by: Andy Polyakov <appro@openssl.org>
If the field separator isn't specified through -nameopt then use
XN_FLAG_SEP_CPLUS_SPC instead of printing nothing and returing an error.
PR#2397
Reviewed-by: Tim Hudson <tjh@openssl.org>
Both now warn once if directory isn't writeable.
Both now warn on file-write errors (multiple times).
Update manpage to describe both program and script correctly.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Having a general fill-column of 78 may look nice at first sight, but
if the edited text gets indented a bit afterward (such as with git
comments in 'git log'), it suddenly turns not so nice on a classic 80
columns terminal. A fill-column of 70 will serve us better.
Reviewed-by: Rich Salz <rsalz@openssl.org>
On Unix/Linux platforms, merge c_rehash script into openssl as a
C program.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
In some environments, such as firmware, the current system time is entirely
meaningless. Provide a clean mechanism to suppress the checks against it.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Remove asn1-kludge option from the req utility. It was a decade old
workaround for CAs and software which required an invalid encoding
of PKCS#10 certificate requests: omitting the attributes field even
though it is not OPTIONAL.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This file, when copied to .dir-locals.el in the OpenSSL source top,
will make sure that the CC mode style "OpenSSL-II" will be used for
all C files.
Additionally, I makes sure that tabs are never used as indentation
character, regardless of the emacs mode, and that the fill column is
78.
Reviewed-by: Rich Salz <rsalz@openssl.org>
If the seed value for dsa key generation is too short (< qsize),
return an error. Also update the documentation.
Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Make all mention of digest algorithm use "any supported algorithm"
RT2071, some new manpages from Victor B. Wagner <vitus@cryptocom.ru>:
X509_LOOKUP_hash_dir.pod
X509_check_ca.pod
X509_check_issued.pod
RT 1600:
Remove references to non-existant objects(3)
Add RETURN VALUES to BIO_do_accept page.
RT1818:
RSA_sign Can return values other than 0 on failure.
RT3634:
Fix AES CBC aliases (Steffen Nurpmeso <sdaoden@yandex.com>)
RT3678:
Some clarifications to BIO_new_pair
(Devchandra L Meetei <dlmeetei@gmail.com>)
RT3787:
Fix some EVP_ function return values
(Laetitia Baudoin <lbaudoin@google.com>)
Reviewed-by: Tim Hudson <tjh@openssl.org>
L<foo|foo> is sub-optimal If the xref is the same as the title,
which is what we do, then you only need L<foo>. This fixes all
1457 occurrences in 349 files. Approximately. (And pod used to
need both.)
Reviewed-by: Richard Levitte <levitte@openssl.org>
This was obsolete in 2001. This is not the same as Gost94 digest.
Thanks to Dmitry Belyavsky <beldmit@gmail.com> for review and advice.
Reviewed-by: Matt Caswell <matt@openssl.org>
Thanks folks:
348 Benjamin Kaduk
317 Christian Brueffer
254 Erik Tews
253 Erik Tews
219 Carl Mehner
155 (ghost)
95 mancha
51 DominikNeubauer
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Add support for loading verify and chain stores in SSL_CONF.
Commands to set verify mode and client CA names.
Add documentation.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
The -show_chain flag to the verify command line app shows information about
the chain that has been built. This commit adds the text "untrusted" against
those certificates that have been used from the untrusted list.
Reviewed-by: Rich Salz <rsalz@openssl.org>
The function X509_verify_cert checks the value of |ctx->chain| at the
beginning, and if it is NULL then it initialises it, along with the value
of ctx->untrusted. The normal way to use X509_verify_cert() is to first
call X509_STORE_CTX_init(); then set up various parameters etc; then call
X509_verify_cert(); then check the results; and finally call
X509_STORE_CTX_cleanup(). The initial call to X509_STORE_CTX_init() sets
|ctx->chain| to NULL. The only place in the OpenSSL codebase where
|ctx->chain| is set to anything other than a non NULL value is in
X509_verify_cert itself. Therefore the only ways that |ctx->chain| could be
non NULL on entry to X509_verify_cert is if one of the following occurs:
1) An application calls X509_verify_cert() twice without re-initialising
in between.
2) An application reaches inside the X509_STORE_CTX structure and changes
the value of |ctx->chain| directly.
With regards to the second of these, we should discount this - it should
not be supported to allow this.
With regards to the first of these, the documentation is not exactly
crystal clear, but the implication is that you must call
X509_STORE_CTX_init() before each call to X509_verify_cert(). If you fail
to do this then, at best, the results would be undefined.
Calling X509_verify_cert() with |ctx->chain| set to a non NULL value is
likely to have unexpected results, and could be dangerous. This commit
changes the behaviour of X509_verify_cert() so that it causes an error if
|ctx->chain| is anything other than NULL (because this indicates that we
have not been initialised properly). It also clarifies the associated
documentation. This is a follow up commit to CVE-2015-1793.
Reviewed-by: Stephen Henson <steve@openssl.org>
Add secure heap for storage of private keys (when possible).
Add BIO_s_secmem(), CBIGNUM, etc.
Add BIO_CTX_secure_new so all BIGNUM's in the context are secure.
Contributed by Akamai Technologies under the Corporate CLA.
Reviewed-by: Richard Levitte <levitte@openssl.org>
This is a workaround so old that nobody remembers what buggy clients
it was for. It's also been broken in stable branches for two years and
nobody noticed (see
https://boringssl-review.googlesource.com/#/c/1694/).
Reviewed-by: Tim Hudson <tjh@openssl.org>
The new accessors SSL_get_client_random, SSL_get_server_random and
SSL_SESSION_get_master_key should return a size_t to match the type of the
|outlen| parameter.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Change the new SSL_get_client_random(), SSL_get_server_random() and
SSL_SESSION_get_master_key() functions to use size_t for |outlen| instead of
int.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Tor uses these values to implement a low-rent clone of RFC 5705 (which,
in our defense, we came up with before RFC 5705 existed). But now that
ssl_st is opaque, we need another way to get at them.
Includes documentation, with suitable warnings about not actually
using these functions.
Signed-off-by: Nick Mathewson <nickm@torproject.org>
Signed-off-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
On the server side, if you want to know which ciphers the client
offered, you had to use session->ciphers. But that field is no
longer visible, so we need a method to get at it.
Signed-off-by: Nick Mathewson <nickm@torproject.org>
Signed-off-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Add support for PKCS#8 private key encryption using the scrypt algorithm
in the pkcs8 utility. Update documentation.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Remove support for the two export grade static DH ciphersuites. These two
ciphersuites were newly added (along with a number of other static DH
ciphersuites) to 1.0.2. However the two export ones have *never* worked
since they were introduced. It seems strange in any case to be adding new
export ciphersuites, and given "logjam" it also does not seem correct to
fix them.
Reviewed-by: Richard Levitte <levitte@openssl.org>
If BN_rand is called with |bits| set to 1 and |top| set to 1 then a 1 byte
buffer overflow can occur. There are no such instances within the OpenSSL at
the moment.
Thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke, Filip Palian for
discovering and reporting this issue.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
The functions BN_rshift and BN_lshift shift their arguments to the right or
left by a specified number of bits. Unpredicatable results (including
crashes) can occur if a negative number is supplied for the shift value.
Thanks to Mateusz Kocielski (LogicalTrust), Marek Kroemeke and Filip Palian
for discovering and reporting this issue.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Given the pervasive nature of TLS extensions it is inadvisable to run
OpenSSL without support for them. It also means that maintaining
the OPENSSL_NO_TLSEXT option within the code is very invasive (and probably
not well tested). Therefore it is being removed.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
- Do not advise generation of DH parameters with dsaparam to save
computation time.
- Promote use of custom parameters more, and explicitly forbid use of
built-in parameters weaker than 2048 bits.
- Advise the callback to ignore <keylength> - it is currently called
with 1024 bits, but this value can and should be safely ignored by
servers.
Reviewed-by: Rich Salz <rsalz@openssl.org>
The default bitlength is now 2048. Also clarify that either the number
of bits or the generator must be present:
$ openssl dhparam -2
and
$ openssl dhparam 2048
generate parameters but
$ openssl dhparam
does not.
Reviewed-by: Matt Caswell <matt@openssl.org>
Rewrite and tidy ASN1_INTEGER and ASN1_ENUMERATED handling.
Remove code duplication.
New functions to convert between int64_t and ASN.1 types without the
quirks of the old long conversion functions.
Add documentation.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Following on from the removal of libcrypto and libssl support for Kerberos
this commit removes all remaining references to Kerberos.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Add SSL_use_certiicate_chain file functions: this is works the same
way as SSL_CTX_use_certificate_chain_file but for an SSL structure.
Update SSL_CONF code to use the new function.
Update docs.
Update ordinals.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Add command line switch entries to table and return SSL_CONF_TYPE_NONE for
them in SSL_CONF_cmd_value_type.
Update docs.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This gets BN_.*free:
BN_BLINDING_free BN_CTX_free BN_FLG_FREE BN_GENCB_free
BN_MONT_CTX_free BN_RECP_CTX_free BN_clear_free BN_free BUF_MEM_free
Also fix a call to DSA_SIG_free to ccgost engine and remove some #ifdef'd
dead code in engines/e_ubsec.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Don't check for NULL before calling a free routine. This gets X509_.*free:
x509_name_ex_free X509_policy_tree_free X509_VERIFY_PARAM_free
X509_STORE_free X509_STORE_CTX_free X509_PKEY_free
X509_OBJECT_free_contents X509_LOOKUP_free X509_INFO_free
Reviewed-by: Richard Levitte <levitte@openssl.org>
Add tables to convert between SSL_CIPHER fields and indices for ciphers
and MACs.
Reorganise ssl_ciph.c to use tables to lookup values and load them.
New functions SSL_CIPHER_get_cipher_nid and SSL_CIPHER_get_digest_nid.
Add documentation.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Add new functions ASN1_TYPE_pack_sequence and ASN1_TYPE_unpack_sequence:
these encode and decode ASN.1 SEQUENCE using an ASN1_TYPE structure.
Update ordinals.
Reviewed-by: Rich Salz <rsalz@openssl.org>
EVP_.*free; this gets:
EVP_CIPHER_CTX_free EVP_PKEY_CTX_free EVP_PKEY_asn1_free
EVP_PKEY_asn1_set_free EVP_PKEY_free EVP_PKEY_free_it
EVP_PKEY_meth_free; and also EVP_CIPHER_CTX_cleanup
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
The recent updates to libssl to enforce stricter return code checking, left
a small number of instances behind where return codes were being swallowed
(typically because the function they were being called from was declared as
void). This commit fixes those instances to handle the return codes more
appropriately.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Support loading of key and certificate from the same file if
SSL_CONF_FLAG_REQUIRE_PRIVATE is set. This is done by remembering the
filename used for each certificate type and attempting to load a private
key from the file when SSL_CONF_CTX_finish is called.
Update docs.
Reviewed-by: Richard Levitte <levitte@openssl.org>
The justification for RAND_pseudo_bytes is somewhat dubious, and the reality
is that it is frequently being misused. RAND_bytes and RAND_pseudo_bytes in
the default implementation both end up calling ssleay_rand_bytes. Both may
return -1 in an error condition. If there is insufficient entropy then
both will return 0, but RAND_bytes will additionally add an error to the
error queue. They both return 1 on success.
Therefore the fundamental difference between the two is that one will add an
error to the error queue with insufficient entory whilst the other will not.
Frequently there are constructions of this form:
if(RAND_pseudo_bytes(...) <= 1)
goto err;
In the above form insufficient entropy is treated as an error anyway, so
RAND_bytes is probably the better form to use.
This form is also seen:
if(!RAND_pseudo_bytes(...))
goto err;
This is technically not correct at all since a -1 return value is
incorrectly handled - but this form will also treat insufficient entropy as
an error.
Within libssl it is required that you have correctly seeded your entropy
pool and so there seems little benefit in using RAND_pseudo_bytes.
Similarly in libcrypto many operations also require a correctly seeded
entropy pool and so in most interesting cases you would be better off
using RAND_bytes anyway. There is a significant risk of RAND_pseudo_bytes
being incorrectly used in scenarios where security can be compromised by
insufficient entropy.
If you are not using the default implementation, then most engines use the
same function to implement RAND_bytes and RAND_pseudo_bytes in any case.
Given its misuse, limited benefit, and potential to compromise security,
RAND_pseudo_bytes has been deprecated.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Start ensuring all OpenSSL "free" routines allow NULL, and remove
any if check before calling them.
This gets DH_free, DSA_free, RSA_free
Reviewed-by: Matt Caswell <matt@openssl.org>
Start ensuring all OpenSSL "free" routines allow NULL, and remove
any if check before calling them.
This gets ASN1_OBJECT_free and ASN1_STRING_free.
Reviewed-by: Matt Caswell <matt@openssl.org>
ACKNOWLEDGEMENTS is now spelled correctly :)
README.ASN1 talked about 0.9.6, so it's deleted.
I turned doc/standards.txt into a set of one-line summaries of RFCs, and
also updated the pointers to original sources (to be web links)
Reviewed-by: Richard Levitte <levitte@openssl.org>
Updates to include SHA224, SHA256, SHA384 and SHA512. In particular note
the restriction on setting md to NULL with regards to thread safety.
Reviewed-by: Tim Hudson <tjh@openssl.org>
SSL_SESSION_get_ticket_lifetime_hint. The latter has been reported as
required to fix Qt for OpenSSL 1.1.0. I have also added the former in order
to determine whether a ticket is present or not - otherwise it is difficult
to know whether a zero lifetime hint is because the server set it to 0, or
because there is no ticket.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Specifically, an ASN.1 NumericString in the certificate CN will fail UTF-8 conversion
and result in a negative return value, which the "x509 -checkhost" command-line option
incorrectly interpreted as success.
Also update X509_check_host docs to reflect reality.
Thanks to Sean Burford (Google) for reporting this issue.
Reviewed-by: Richard Levitte <levitte@openssl.org>
There is no mechanism to do that at the moment - SSL_set_bio makes changes
to the wbio even if you pass in SSL_get_wbio().
This commit introduces two new API functions SSL_set_rbio() and
SSL_set_wbio(). These do the same job as SSL_set_bio() except they enable
you to manage the rbio and wbio individually.
Reviewed-by: Tim Hudson <tjh@openssl.org>
This is an ancient bug workaround for Netscape clients. The documentation
talks about versions 3.x and 4.x beta.
Reviewed-by: Tim Hudson <tjh@openssl.org>
Document SSL_get_extms_support().
Modify behaviour of SSL_get_extms_support() so it returns -1 if the
master secret support of the peer is not known (e.g. handshake in progress).
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Not interested in helping the NSA in the slightest.
And anyway, it was never implemented, #if'd out.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Remove OPENSSL_NO_BUF_FREELISTS. This was turned on by default,
so the work here is removing the 'maintain our own freelist' code.
Also removed a minor old Windows-multibyte/widechar conversion flag.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Remove support for SHA0 and DSS0 (they were broken), and remove
the ability to attempt to build without SHA (it didn't work).
For simplicity, remove the option of not building various SHA algorithms;
you could argue that SHA_224/256/384/512 should be kept, since they're
like crypto algorithms, but I decided to go the other way.
So these options are gone:
GENUINE_DSA OPENSSL_NO_SHA0
OPENSSL_NO_SHA OPENSSL_NO_SHA1
OPENSSL_NO_SHA224 OPENSSL_NO_SHA256
OPENSSL_NO_SHA384 OPENSSL_NO_SHA512
Reviewed-by: Richard Levitte <levitte@openssl.org>
Per discussion: should not exit. Should not print to stderr.
Errors are ignored. Updated doc to reflect that, and the fact
that this function is to be avoided.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Removed CHANGES.SSLeay
Udpate README to be current.
Updated fignerprints.txt to list only current release signers and
to explain that is what it's used for.
Removed the following:
c-indentation.el -- doesn't go with our coding style
openssl-shared.txt -- old info about shared library aides
openssl.txt -- old info about X509v3 extension support/syntax
ssleay.txt -- old info about OpenSSL's predecessor, back when
programmers coded on COBOL sheets by candlelight
Reviewed-by: Richard Levitte <levitte@openssl.org>
Show only the #define, not the values, in BIO_f_buffer. Data
abstraction and we can remove a "see also" entry.
Remove internal forward reference to NOTES in EVP_EncryptInit; just
say "see below" as we do in the other pages.
Add missing (3) in pem.pod so the L<> entry is consistent.
Fix entry to point to the "master" page, not the symlink'd one.
Reviewed-by: Matt Caswell <matt@openssl.org>
OpenSSL clients would tolerate temporary RSA keys in non-export
ciphersuites. It also had an option SSL_OP_EPHEMERAL_RSA which
enabled this server side. Remove both options as they are a
protocol violation.
Thanks to Karthikeyan Bhargavan for reporting this issue.
(CVE-2015-0204)
Reviewed-by: Matt Caswell <matt@openssl.org>
MS Server gated cryptography is obsolete and dates from the time of export
restrictions on strong encryption and is only used by ancient versions of
MSIE.
Reviewed-by: Matt Caswell <matt@openssl.org>
* adds links to various related documents.
* fixes a few typos.
* rewords a few sentences.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
In EVP_EncryptInit remove duplicate mention of EVP_idea_cbc()
In EVP_PKEY_CTX_ctrl.pod remove EVP_PKEY_get_default_digest_nid
since it is documented elsewhere.
Reviewed-by: Richard Levitte <levitte@openssl.org>
The current documentation contains a bunch of spelling and grammar mistakes. I also
found it hard to understand some paragraphs, so here is my attempt to improve its
readability.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Fix CONF_load_modules to CONF_modules_load.
Document that it calls exit.
Advise against using it now.
Add an error print to stderr.
Reviewed-by: Matt Caswell <matt@openssl.org>
Out is the buffer which needs to contain at least inl + cipher_block_size - 1 bytes. Outl
is just an int*.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
If data is NULL, return the size needed to hold the
derived key. No other API to do this, so document
the behavior.
Reviewed-by: Richard Levitte <levitte@openssl.org>
pod2man now complains when item tags are not sequential.
Also complains about missing =back and other tags.
Silence the warnings; most were already done.
Reviewed-by: Tim Hudson <tjh@openssl.org>
The original RT request included a patch. By the time
we got around to doing it, however, the callback scheme
had changed. So I wrote a new function RSA_check_key_ex()
that uses the BN_GENCB callback. But thanks very much
to Vinet Sharma <vineet.sharma@gmail.com> for the
initial implementation.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
i2d_re_X509_tbs re-encodes the TBS portion of the certificate.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Dr Stephen Henson <steve@openssl.org>
RT842, closed back in 2004, changed the default serial number
to be a random number rather than zero. Finally time to update
the doc
Reviewed-by: Tim Hudson <tjh@openssl.org>
Add .crt/.cer/.crl to the filenames parsed.
I also updated the podpage (since it didn't exist when
this ticket was first created, nor when it was re-created
seven years later).
Reviewed-by: Tim Hudson <tjh@openssl.org>
Re-order algorithm list.
Be consistent in command synopsis.
Add content about signing.
Add EXAMPLE section
Add some missing options: -r, -fips-fingerprint -non-fips-allow
Various other fixes.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Andy found an additional typo "can be can be".
Now I have that silly "Que sera sera" song stuck in my head.
Reviewed-by: Andy Polyakov <appro@openssl.org>
RT1665: aes documentation.
Paul Green wrote a nice aes.pod file.
But we now encourage the EVP interface.
So I took his RT item and used it as impetus to add
the AES modes to EVP_EncryptInit.pod
I also noticed that rc4.pod has spurious references to some other
cipher pages, so I removed them.
RT2300: Clean up MD history (merged into RT1665)
Put HISTORY section only in EVP_DigestInit.pod. Also add words
to discourage use of older cipher-specific API, and remove SEE ALSO
links that point to them.
Make sure digest pages have a NOTE that says use EVP_DigestInit.
Review feedback:
More cleanup in EVP_EncryptInit.pod
Fixed SEE ALSO links in ripemd160.pod, sha.pod, mdc2.pod, blowfish.pod,
rc4.d, and des.pod. Re-order sections in des.pod for consistency
Reviewed-by: Matt Caswell <matt@openssl.org>
When d2i_ECPrivateKey reads a private key with a missing (optional) public key,
generate one automatically from the group and private key.
Reviewed-by: Dr Stephen Henson <steve@openssl.org>
The description of when the server creates a DH key is
confusing. This cleans it up.
(rsalz: also removed trailing whitespace.)
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
The EXAMPLE that used FILE and RC2 doesn't compile due to a
few minor errors. Tweak to use IDEA and AES-128. Remove
examples about RC2 and RC5.
Reviewed-by: Emilia Kasper <emilia@openssl.org>
While RFC6367 focuses on Camellia-GCM cipher suites, it also adds a few
cipher suites that use SHA-2 based HMAC that can be very easily
added.
Tested against gnutls 3.3.5
PR#3443
Reviewed-by: Tim Hudson <tjh@openssl.org>
In two OpenSSL manual pages, in the NAME section, the last word of the
name list is followed by a stray trailing comma. While this may seem
minor, it is worth fixing because it may confuse some makewhatis(8)
implementations.
While here, also add the missing word "size" to the one line
description in SSL_CTX_set_max_cert_list(3).
Reviewed by: Dr Stephen Henson <shenson@drh-consultancy.co.uk>
Update the dgst.pod page to include SHA224...512 algorithms.
Update apps/progs.pl to add them to the digest command table.
Reviewed-by: Tim Hudson <tjh@cryptosoft.com>