By using non-DER or invalid encodings outside the signed portion of a
certificate the fingerprint can be changed without breaking the signature.
Although no details of the signed portion of the certificate can be changed
this can cause problems with some applications: e.g. those using the
certificate fingerprint for blacklists.

1. Reject signatures with non zero unused bits.

If the BIT STRING containing the signature has non zero unused bits reject the
signature. All current signature algorithms require zero unused bits.

2. Check certificate algorithm consistency.

Check the AlgorithmIdentifier inside TBS matches the one in the certificate
signature. NB: this will result in signature failure errors for some broken
certificates.

3. Check DSA/ECDSA signatures use DER.

Reencode DSA/ECDSA signatures and compare with the original received signature.
Return an error if there is a mismatch.

This will reject various cases including garbage after signature (thanks to
Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS program for
discovering this case) and use of BER or invalid ASN.1 INTEGERs (negative or
with leading zeroes).

CVE-2014-8275

(Imported from upstream's 85cfc188c0 and
4c52816d35)

Change-Id: Ic901aea8ea6457df27dc542a11c30464561e322b
Reviewed-on: https://boringssl-review.googlesource.com/2783
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>

The same library code applies for both the error and the function, so modules
cannot easily report errors from each other. Switch evp/algorithm.c's error
codes to the EVP library. Remove the original error codes so it's obvious some
changes are needed.

- X509_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED -> EVP_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED
  ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED -> EVP_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED
  (Actually, the X509 version of this error code doesn't exist in OpenSSL. It should
   have been ASN1.)

- ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM -> EVP_R_UNKNOWN_SIGNATURE_ALGORITHM

- ASN1_R_WRONG_PUBLIC_KEY_TYPE -> EVP_R_WRONG_PUBLIC_KEY_TYPE

- ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM -> EVP_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM

Change-Id: I05b1a05b465d800c85f7d63ca74588edf40847b9
Reviewed-on: https://boringssl-review.googlesource.com/1940
Reviewed-by: Adam Langley <agl@google.com>

Previously, public headers lived next to the respective code and there
were symlinks from include/openssl to them.

This doesn't work on Windows.

This change moves the headers to live in include/openssl. In cases where
some symlinks pointed to the same header, I've added a file that just
includes the intended target. These cases are all for backwards-compat.

Change-Id: I6e285b74caf621c644b5168a4877db226b07fd92
Reviewed-on: https://boringssl-review.googlesource.com/1180
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>

Initial fork from f2d678e6e8 (1.0.2 beta).

(This change contains substantial changes from the original and
effectively starts a new history.)