BN_bin2bn takes a size_t as it should, but it passes that into bn_wexpand which
takes unsigned. Switch bn_wexpand and bn_expand to take size_t before they
check bounds against INT_MAX.

BIGNUM itself still uses int everywhere and we may want to audit all the
arithmetic at some point. Although I suspect having bn_expand require that the
number of bits fit in an int is sufficient to make everything happy, unless
we're doing interesting arithmetic on the number of bits somewhere.

Change-Id: Id191a4a095adb7c938cde6f5a28bee56644720c6
Reviewed-on: https://boringssl-review.googlesource.com/5680
Reviewed-by: Adam Langley <agl@google.com>

Much of this was done automatically with
  find . -name '*.c' | xargs sed -E -i '' -e 's/(OPENSSL_PUT_ERROR\([a-zA-Z_0-9]+, )[a-zA-Z_0-9]+, ([a-zA-Z_0-9]+\);)/\1\2/'
  find . -name '*.c' | xargs sed -E -i '' -e 's/(OPENSSL_PUT_ERROR\([a-zA-Z_0-9]+, )[a-zA-Z_0-9]+,  ([a-zA-Z_0-9]+\);)/\1\2/'

BUG=468039

Change-Id: I4c75fd95dff85ab1d4a546b05e6aed1aeeb499d8
Reviewed-on: https://boringssl-review.googlesource.com/5276
Reviewed-by: Adam Langley <agl@google.com>

First batch of the alphabet.

Change-Id: If4e60f4fbb69e04eb4b70aa1b2240e329251bfa5
Reviewed-on: https://boringssl-review.googlesource.com/4514
Reviewed-by: Adam Langley <agl@google.com>

Everything before crypto/ec.

Change-Id: Icbfab8e4ffe5cc56bf465eb57d3fdad3959a085c
Reviewed-on: https://boringssl-review.googlesource.com/3401
Reviewed-by: Adam Langley <agl@google.com>

Including string.h in base.h causes any file that includes a BoringSSL
header to include string.h. Generally this wouldn't be a problem,
although string.h might slow down the compile if it wasn't otherwise
needed. However, it also causes problems for ipsec-tools in Android
because OpenSSL didn't have this behaviour.

This change removes string.h from base.h and, instead, adds it to each
.c file that requires it.

Change-Id: I5968e50b0e230fd3adf9b72dd2836e6f52d6fb37
Reviewed-on: https://boringssl-review.googlesource.com/3200
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.)