#include?“md5.h“

/*????The?below?was?retrieved?from
?*????http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/crypto/md5.c?rev=1.1
?*????with?the?following?changes:
?*????#includes?commented?out.
?*????Support?context->count?as?unsigned?int[2]?instead?of?uint64_t
?*????u_int*?to?uint*
?*/

/*
?*?This?code?implements?the?MD5?message-digest?algorithm.
?*?The?algorithm?is?due?to?Ron?Rivest.????This?code?was
?*?written?by?Colin?Plumb?in?1993?no?copyright?is?claimed.
?*?This?code?is?in?the?public?domain;?do?with?it?what?you?wish.
?*
?*?Equivalent?code?is?available?from?RSA?Data?Security?Inc.
?*?This?code?has?been?tested?against?that?and?is?equivalent
?*?except?that?you?don‘t?need?to?include?two?pages?of?legalese
?*?with?every?copy.
?*
?*?To?compute?the?message?digest?of?a?chunk?of?bytes?declare?an
?*?MD5Context?structure?pass?it?to?MD5Init?call?MD5Update?as
?*?needed?on?buffers?full?of?bytes?and?then?call?MD5Final?which
?*?will?fill?a?supplied?16-byte?array?with?the?digest.
?*/

/*#include?*/
/*#include?*/
/*#include?*/

#define?PUT_64BIT_LE（cp?value）?do?{????????????????\
????（cp）[7]?=?（value）[1]?>>?24;????????????????????\
????（cp）[6]?=?（value）[1]?>>?16;????????????????????\
????（cp）[5]?=?（value）[1]?>>?8;????????????????????\
????（cp）[4]?=?（value）[1];????????????????????????\
????（cp）[3]?=?（value）[0]?>>?24;????????????????????\
????（cp）[2]?=?（value）[0]?>>?16;????????????????????\
????（cp）[1]?=?（value）[0]?>>?8;????????????????????\
????（cp）[0]?=?（value）[0];?}?while?（0）

#define?PUT_32BIT_LE（cp?value）?do?{????????????????????\
????（cp）[3]?=?（value）?>>?24;????????????????????\
????（cp）[2]?=?（value）?>>?16;????????????????????\
????（cp）[1]?=?（value）?>>?8;????????????????????????\
????（cp）[0]?=?（value）;?}?while?（0）

static?unsigned?char?PADDING[MD5_BLOCK_LENGTH]?=?{
????0x80?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0
????0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0
????0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0?0
};

/*
?*?Start?MD5?accumulation.??Set?bit?count?to?0?and?buffer?to?mysterious
?*?initialization?constants.
?*/
void
MD5Init（MD5_CTX?*ctx）
{
????ctx->count[0]?=?0;
????ctx->count[1]?=?0;
????ctx->state[0]?=?0x67452301;
????ctx->state[1]?=?0xefcdab89;
????ctx->state[2]?=?0x98badcfe;
????ctx->state[3]?=?0x10325476;
}

/*
?*?Update?context?to?reflect?the?concatenation?of?another?buffer?full
?*?of?bytes.
?*/
void
MD5Update（MD5_CTX?*ctx?unsigned?char?const?*input?size_t?len）
{
????size_t?have?need;

????/*?Check?how?many?bytes?we?already?have?and?how?many?more?we?need.?*/
????have?=?（size_t）（（ctx->count[0]?>>?3）?&?（MD5_BLOCK_LENGTH?-?1））;
????need?=?MD5_BLOCK_LENGTH?-?have;

????/*?Update?bitcount?*/
/*????ctx->count?+=?（uint64_t）len?<????if?（（ctx->count[0]?+=?（（unsigned?int）len?<????/*?Overflowed?ctx->count[0]?*/
????