If a certificate chain contains no certificate which can be validated
as a standalone certificate (i.e. contains no trusted root
certificates or previously-validated certificates) then iPXE will
currently return a fixed error EACCES_UNTRUSTED. This masks the
actual errors obtained when attempting to validate each certificate as
a standalone certificate, and so makes troubleshooting difficult for
the end user.
Fix by instead returning the error obtained when attempting to
validate the final certificate in the chain as a standalone
certificate. This error is most likely (though not guaranteed) to
represent the "real" problem.
Reported-by: Sven Dreyer <sven@dreyer-net.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Discarding the active ARP cache entry in the middle of a download will
substantially disrupt the TCP stream. Try to minimise any such
disruption by treating ARP cache entries as expensive, and discarding
them only when nothing else is available to discard.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE has no concept of the local time zone, mainly because there is no
viable way to obtain time zone information in the absence of local
state. This causes potential problems with newly-issued certificates
and certificates that are about to expire.
Avoid such problems by allowing an error margin of around 12 hours on
certificate validity periods, similar to the error margin already
allowed for OCSP response timestamps.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The setting name "key" conflicts with the setting name "key" already
in use by the 802.11 code. Resolve the conflict by renaming the newer
setting to "privkey".
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add support for constructing OCSP queries and parsing OCSP responses.
(There is no support yet for actually issuing an OCSP query via an
HTTP POST.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
X.509 certificate processing currently produces an overwhelming amount
of debugging information. Move some of this from DBGLVL_LOG to
DBGLVL_EXTRA, to make the output more manageable.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
CMS includes an unordered certificate set, from which certificates
must be extracted in order by matching up issuers with subjects. We
will use the same functionality as part of the automatic download of
cross-signing certificates. Generalise cms_find_subject() to
x509_find_subject(), and create x509_auto_append().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
At present, certificate chain validation is treated as an
instantaneous process that can be carried out using only data that is
already in memory. This model does not allow for validation to
include non-instantaneous steps, such as downloading a cross-signing
certificate, or determining certificate revocation status via OCSP.
Redesign the internal representation of certificate chains to allow
chains to outlive the scope of the original source of certificates
(such as a TLS Certificate record).
Allow for certificates to be cached, so that each certificate needs to
be validated only once.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
If a root certificate has been explicitly specified at build time
using TRUST=/path/to/cert then do not allow this to be overridden even
from a trustworthy settings source (such as VMware GuestInfo).
Similarly, if a client certificate (and private key) has been
explicitly specified at build time, then do not allow it to be
overridden at runtime.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Changing the trusted root certificate currently requires a rebuild of
the iPXE binary, which may be inconvenient or impractical.
Allow the list of trusted root certificate fingerprints to be
overridden using the "trust" setting, but only at the point of iPXE
initialisation. This prevents untrusted sources of settings
(e.g. DHCP) from subverting the chain of trust, while allowing
trustworthy sources to change the trusted root certificate without
requiring a rebuild.
The basic idea is that if you are able to manipulate a trustworthy
source of settings (e.g. VMware GuestInfo or non-volatile stored
options), then you would be able to replace the iPXE binary anyway,
and so no security is lost by allowing such sources to override the
list of trusted root certificates.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Use explicit size in memset because 8 bytes must be set always.
This problem was reported by cppcheck.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The Cryptographic Message Syntax (PKCS#7) provides a format for
encapsulating digital signatures of arbitrary binary blobs. A
signature can be generated using
openssl cms -sign -in <file to sign> -binary -noattr \
-signer <signer>.crt -inkey <signer>.key -certfile <CA>.crt \
-outform DER -out <signature>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The certificate may be part of an ASN.1-encoded certificate chain, and
so may not be the only object contained within the ASN.1 cursor.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
asn1_skip() will return an error on reaching the end of an object, and
so should not be used as the basis for asn1_shrink().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The concept of an OID-identified algorithm as defined in X.509 is used
in some other standards (e.g. PKCS#7). Generalise this functionality
and provide it as part of the ASN.1 core.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow a client certificate and corresponding private key to be
specified at build time using the syntax
make CERT=/path/to/certificate KEY=/path/to/key
The build process uses openssl to convert the files into DER format,
and includes them within the client certificate store in
clientcert.c. The build process will prompt for the private key
password if applicable.
Note that the private key is stored unencrypted, and so the resulting
iPXE binary (and the temporary files created during the build process)
should be treated as being equivalent to an unencrypted private key
file.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
bigint_mod_multiply() and bigint_mod_exp() require a fixed amount of
temporary storage for intermediate results. (The amount of temporary
storage required depends upon the size of the integers involved.)
When performing calculations for 4096-bit RSA the amount of temporary
storage space required will exceed 2.5kB, which is too much to
allocate on the stack. Avoid this problem by forcing the caller to
allocate temporary storage.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Avoid a compiler warning on some versions of gcc by using real
function prototypes.
Reported-by: Rob Shelley <Rob@cirris.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
RSA requires modular exponentiation using arbitrarily large integers.
Given the sizes of the modulus and exponent, all required calculations
can be done without any further dynamic storage allocation. The x86
architecture allows for efficient large integer support via inline
assembly using the instructions that take advantage of the carry flag
(e.g. "adcl", "rcrl").
This implemention is approximately 80% smaller than the (more generic)
AXTLS implementation.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
All axTLS files are now vanilla versions of the upstream axTLS files,
with one minor exception: the unused "ctx" parameter of
bi_int_divide() has been marked with "__unused" to avoid a compilation
error.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Replace MD5 implementation with one which is around 20% smaller. This
implementation has been verified using the existing MD5 self-tests.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Replace SHA-1 implementation from AXTLS with a dedicated iPXE
implementation which is around 40% smaller. This implementation has
been verified using the existing SHA-1 self-tests (including the NIST
SHA-1 test vectors).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
RSA requires the generation of random non-zero bytes (i.e. a sequence
of random numbers in the range [0x01,0xff]). ANS X9.82 provides
various Approved methods for converting random bits into random
numbers. The simplest such method is the Simple Discard Method.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies that the start-up tests shall consist of at least
one full cycle of the continuous tests.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies several Approved Sources of Entropy Input (SEI).
One such SEI uses an entropy source as the Source of Entropy Input,
condensing each entropy source output after each GetEntropy call.
This can be implemented relatively cheaply in iPXE and avoids the need
to allocate potentially very large buffers.
(Note that the terms "entropy source" and "Source of Entropy Input"
are not synonyms within the context of ANS X9.82.)
Use the iPXE API mechanism to allow entropy sources to be selected at
compilation time.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Treat an empty (zeroed) DRBG as invalid. This ensures that a DRBG
that has not yet been instantiated (or that has been uninstantiated)
will refuse to attempt to generate random bits.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies several Approved derivation functions for use in
distributing entropy throughout a buffer. One such derivation
function is Hash_df, which can be implemented using the existing iPXE
SHA-1 functionality.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies that an Approved DRBG must consist of an Approved
algorithm wrapped inside an envelope which handles entropy gathering,
prediction resistance, automatic reseeding and other housekeeping
tasks.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Cryptographic random number generation requires an entropy source,
which is used as the input to a Deterministic Random Bit Generator
(DRBG).
iPXE does not currently have a suitable entropy source. Provide a
dummy source to allow the DRBG code to be implemented.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 specifies several Approved algorithms for use in a
Deterministic Random Bit Generator (DRBG). One such algorithm is
HMAC_DRBG, which can be implemented using the existing iPXE SHA-1 and
HMAC functionality. This algorithm provides a maximum security
strength of 128 bits.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The version field of an X.509 certificate appears to be optional.
Reported-by: Sebastiano Manusia <Sebastiano.Manusia@chuv.ch>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Changes were made to files where the licence text within the files
themselves confirms that the files are GPL version 2 or later.
Signed-off-by: Shao Miller <shao.miller@yrdsb.edu.on.ca>
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Access to the gpxe.org and etherboot.org domains and associated
resources has been revoked by the registrant of the domain. Work
around this problem by renaming project from gPXE to iPXE, and
updating URLs to match.
Also update README, LOG and COPYRIGHTS to remove obsolete information.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Both of these routines are used by 802.11 WPA, but they are generic
and could be needed by other protocols as well.
Signed-off-by: Marty Connor <mdc@etherboot.org>
It is a programming error, not a runtime error, if we attempt to use
block ciphers with an incorrect blocksize, so use an assert() rather
than an error status return.
The various types of cryptographic algorithm are fundamentally
different, and it was probably a mistake to try to handle them via a
single common type.
pubkey_algorithm is a placeholder type for now.
Michael Brown