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>
OIDs are theoretically part of a global hierarchy. However, the
hierarchy is sufficiently disorganised as to be essentially
meaningless for all purposes other than guaranteeing uniqueness.
Ignore the hierarchical nature of OIDs and treat them as opaque.
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>
Simplify code by recording the active handshake digest algorithm as a
session parameter. (Note that we must still accumulate digests for
all supported algorithms, since we don't know which digest will
eventually be used until we receive the Server Hello.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
TLSv1.1 and earlier use a hybrid of MD5 and SHA-1 to generate digests
over the handshake messages. Formalise this as a separate digest
algorithm "md5+sha1".
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>
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>
Both HMAC_DRBG using SHA-1 and HMAC_DRBG using SHA-256 are Approved
algorithms in ANS X9.82 for our chosen security strength of 128 bits.
However, general recommendations (see e.g. NIST SP800-57) are to use a
larger hash function in preference to SHA-1.
Since SHA-256 is required anyway for TLSv1.2 support, there is no code
size penalty for switching HMAC_DRBG to also use SHA-256.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
ANS X9.82 Part 4 (April 2011 Draft) Section 13.3.4.2 states that "When
using the derivation function based on a hash function, the output
length of the hash function shall meet or exceed the security strength
indicated by the min_entropy parameter in the Get_entropy_input call",
although this criteria is missing from the pseudocode provided in the
same section.
Add a test for this condition, and upgrade from SHA-1 to SHA-256 since
SHA-1 has an output length of 160 bits, which is insufficient for
generating the (128 * 3/2 = 192) bits required when instantiating the
128-bit strength DRBG.
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>
Advertise support for TLS version 1.1, and be prepared to downgrade to
TLS version 1.0. Tested against Apache with mod_gnutls, using the
GnuTLSPriorities directive to force specific protocol versions.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow packet transmission to be deferred pending successful ARP
resolution. This avoids the time spent waiting for a higher-level
protocol (e.g. TCP or TFTP) to attempt retransmission.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some PXE stacks (observed with a QLogic 8242) will always try to
prepend a link-layer header, even if the caller uses P_UNKNOWN to
indicate that the link-layer header has already been filled in. This
results in an invalid packet being transmitted.
Work around these faulty PXE stacks where possible by stripping the
existing link-layer header and allowing the PXE stack to (re)construct
the link-layer header itself.
Originally-fixed-by: Buck Huppmann <buckh@pobox.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some iSCSI targets respond to a PDU before receiving the padding
bytes. If the target responds quickly enough, this can cause iPXE to
start processing a new TX PDU before the padding bytes have been sent,
which results in a protocol violation.
Fix by always transmitting the padding bytes along with the data
segment.
Originally-fixed-by: Shyam Iyer <shyam_iyer@dell.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Abstract out the generic line-handling portions of the syslog
putchar() routine, to allow use by other console types.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
