Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Use unsigned comparisons. Prior to this commit, SHA1_Update and
RIPEMD160_Update were broken when all of the following conditions
applied:
(1) The platform is i386.
(2) The program calling *_Update is statically linked to libmd.
(3) The buffer provided to *_Update is aligned modulo 4 bytes.
(4) The buffer extends beyond 2GB.

Due to the design of this code, SHA1_Update and RIPEMD160_Update will
still be broken if conditions (1)-(3) apply AND the buffer extends
beyond 4GB (i.e., there is an integer overflow in computing "data + len").
Since this remaining bug simply replaces SIGSEGV with a bogus hash (and
non-broken programs should never provide such operands) I don't consider
it to be a serious problem.

MFC After: 1 week
PR: kern/102795

fix for incorrect specification of alignment (it worked for the elf
build, but broke while doing the aout legacy build). Now using
.p2align instead of .align. Fixes broken buildworld.

Submitted by: John Polstra
Reviewed by: John Polstra

Fix bug in MDx test suite.
Add Eric Young's SHA-[01] implementations.