File: [local] / src / sys / crypto / cryptosoft.c (download)
Revision 1.15, Sun Oct 15 01:12:24 2000 UTC (23 years, 7 months ago) by angelos
Branch: MAIN
CVS Tags: OPENBSD_2_8_BASE, OPENBSD_2_8 Changes since 1.14: +7 -0 lines
Forgot to commit this, necessary for AES support.
|
/* $OpenBSD: cryptosoft.c,v 1.15 2000/10/15 01:12:24 angelos Exp $ */
/*
* The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
*
* This code was written by Angelos D. Keromytis in Athens, Greece, in
* February 2000. Network Security Technologies Inc. (NSTI) kindly
* supported the development of this code.
*
* Copyright (c) 2000 Angelos D. Keromytis
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all source code copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
#include <sys/errno.h>
#include <sys/md5k.h>
#include <dev/rndvar.h>
#include <crypto/sha1.h>
#include <crypto/rmd160.h>
#include <crypto/cast.h>
#include <crypto/skipjack.h>
#include <crypto/blf.h>
#include <crypto/crypto.h>
#include <crypto/cryptosoft.h>
#include <crypto/xform.h>
u_int8_t hmac_ipad_buffer[64] = {
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36 };
u_int8_t hmac_opad_buffer[64] = {
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C,
0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C, 0x5C };
struct swcr_data **swcr_sessions = NULL;
u_int32_t swcr_sesnum = 0;
int32_t swcr_id = -1;
/*
* Apply a symmetric encryption/decryption algorithm.
*/
int
swcr_encdec(struct cryptodesc *crd, struct swcr_data *sw, caddr_t buf,
int outtype)
{
unsigned char iv[EALG_MAX_BLOCK_LEN], blk[EALG_MAX_BLOCK_LEN], *idat;
unsigned char *ivp, piv[EALG_MAX_BLOCK_LEN];
struct enc_xform *exf;
int i, k, j, blks;
struct mbuf *m;
exf = sw->sw_exf;
blks = exf->blocksize;
/* Check for non-padded data */
if (crd->crd_len % blks)
return EINVAL;
if (outtype == CRYPTO_BUF_CONTIG)
{
if (crd->crd_flags & CRD_F_ENCRYPT)
{
/* IV explicitly provided ? */
if (crd->crd_flags & CRD_F_IV_EXPLICIT)
bcopy(crd->crd_iv, sw->sw_iv, blks);
if (!(crd->crd_flags & CRD_F_IV_PRESENT))
bcopy(sw->sw_iv, buf + crd->crd_inject, blks);
for (i = crd->crd_skip;
i < crd->crd_skip + crd->crd_len;
i += blks)
{
/* XOR with the IV/previous block, as appropriate. */
if (i == crd->crd_skip)
for (k = 0; k < blks; k++)
buf[i + k] ^= sw->sw_iv[k];
else
for (k = 0; k < blks; k++)
buf[i + k] ^= buf[i + k - blks];
exf->encrypt(sw->sw_kschedule, buf + i);
}
/* Keep the last block */
bcopy(buf + crd->crd_len - blks, sw->sw_iv, blks);
}
else /* Decrypt */
{
/* IV explicitly provided ? */
if (crd->crd_flags & CRD_F_IV_EXPLICIT)
bcopy(crd->crd_iv, sw->sw_iv, blks);
else /* IV preceeds data */
bcopy(buf + crd->crd_inject, sw->sw_iv, blks);
/*
* Start at the end, so we don't need to keep the encrypted
* block as the IV for the next block.
*/
for (i = crd->crd_skip + crd->crd_len - blks;
i >= crd->crd_skip;
i -= blks)
{
exf->decrypt(sw->sw_kschedule, buf + i);
/* XOR with the IV/previous block, as appropriate */
if (i == crd->crd_skip)
for (k = 0; k < blks; k++)
buf[i + k] ^= sw->sw_iv[k];
else
for (k = 0; k < blks; k++)
buf[i + k] ^= buf[i + k - blks];
}
}
return 0; /* Done with contiguous buffer encryption/decryption */
}
else /* mbuf */
{
m = (struct mbuf *) buf;
/* Initialize the IV */
if (crd->crd_flags & CRD_F_ENCRYPT)
{
/* IV explicitly provided ? */
if (crd->crd_flags & CRD_F_IV_EXPLICIT)
bcopy(crd->crd_iv, iv, blks);
else
bcopy(sw->sw_iv, iv, blks); /* Use IV from context */
/* Do we need to write the IV */
if (!(crd->crd_flags & CRD_F_IV_PRESENT))
m_copyback(m, crd->crd_inject, blks, iv);
}
else /* Decryption */
{
/* IV explicitly provided ? */
if (crd->crd_flags & CRD_F_IV_EXPLICIT)
bcopy(crd->crd_iv, iv, blks);
else
m_copydata(m, crd->crd_inject, blks, iv); /* Get IV off mbuf */
}
ivp = iv;
/* Find beginning of data */
m = m_getptr(m, crd->crd_skip, &k);
if (m == NULL)
return EINVAL;
i = crd->crd_len;
while (i > 0)
{
/*
* If there's insufficient data at the end of an mbuf, we have
* to do some copying.
*/
if ((m->m_len < k + blks) && (m->m_len != k))
{
m_copydata(m, k, blks, blk);
/* Actual encryption/decryption */
if (crd->crd_flags & CRD_F_ENCRYPT)
{
/* XOR with previous block */
for (j = 0; j < blks; j++)
blk[j] ^= ivp[j];
exf->encrypt(sw->sw_kschedule, blk);
/* Keep encrypted block for XOR'ing with next block */
bcopy(blk, iv, blks);
ivp = iv;
}
else /* decrypt */
{
/* Keep encrypted block for XOR'ing with next block */
if (ivp == iv)
bcopy(blk, piv, blks);
else
bcopy(blk, iv, blks);
exf->decrypt(sw->sw_kschedule, blk);
/* XOR with previous block */
for (j = 0; j < blks; j++)
blk[j] ^= ivp[j];
if (ivp == iv)
bcopy(piv, iv, blks);
else
ivp = iv;
}
/* Copy back decrypted block */
m_copyback(m, k, blks, blk);
/* Advance pointer */
m = m_getptr(m, k + blks, &k);
if (m == NULL)
return EINVAL;
i -= blks;
/* Could be done... */
if (i == 0)
break;
}
/* Skip possibly empty mbufs */
if (k == m->m_len)
{
for (m = m->m_next; m && m->m_len == 0; m = m->m_next)
;
k = 0;
}
/* Sanity check */
if (m == NULL)
return EINVAL;
/*
* Warning: idat may point to garbage here, but we only use it
* in the while() loop, only if there are indeed enough data.
*/
idat = mtod(m, unsigned char *) + k;
while ((m->m_len >= k + blks) && (i > 0))
{
if (crd->crd_flags & CRD_F_ENCRYPT)
{
/* XOR with previous block/IV */
for (j = 0; j < blks; j++)
idat[j] ^= ivp[j];
exf->encrypt(sw->sw_kschedule, idat);
ivp = idat;
}
else /* decrypt */
{
/*
* Keep encrypted block to be used in next block's
* processing.
*/
if (ivp == iv)
bcopy(idat, piv, blks);
else
bcopy(idat, iv, blks);
exf->decrypt(sw->sw_kschedule, idat);
/* XOR with previous block/IV */
for (j = 0; j < blks; j++)
idat[j] ^= ivp[j];
if (ivp == iv)
bcopy(piv, iv, blks);
else
ivp = iv;
}
idat += blks;
k += blks;
i -= blks;
}
}
/* Keep the last block */
if (crd->crd_flags & CRD_F_ENCRYPT)
bcopy(ivp, sw->sw_iv, blks);
return 0; /* Done with mbuf encryption/decryption */
}
/* Unreachable */
return EINVAL;
}
/*
* Compute keyed-hash authenticator.
*/
int
swcr_authcompute(struct cryptodesc *crd, struct swcr_data *sw,
caddr_t buf, int outtype)
{
unsigned char aalg[AALG_MAX_RESULT_LEN];
struct auth_hash *axf;
union authctx ctx;
int err;
if (sw->sw_ictx == 0)
return EINVAL;
axf = sw->sw_axf;
bcopy(sw->sw_ictx, &ctx, axf->ctxsize);
if (outtype == CRYPTO_BUF_CONTIG)
axf->Update(&ctx, buf + crd->crd_skip, crd->crd_len);
else
{
err = m_apply((struct mbuf *) buf, crd->crd_skip,
crd->crd_len,
(int (*)(caddr_t, caddr_t, unsigned int)) axf->Update,
(caddr_t) &ctx);
if (err)
return err;
}
switch (sw->sw_alg)
{
case CRYPTO_MD5_HMAC96:
case CRYPTO_SHA1_HMAC96:
case CRYPTO_RIPEMD160_HMAC96:
if (sw->sw_octx == NULL)
return EINVAL;
axf->Final(aalg, &ctx);
bcopy(sw->sw_octx, &ctx, axf->ctxsize);
axf->Update(&ctx, aalg, axf->hashsize);
axf->Final(aalg, &ctx);
break;
case CRYPTO_MD5_KPDK:
case CRYPTO_SHA1_KPDK:
if (sw->sw_octx == NULL)
return EINVAL;
axf->Update(&ctx, sw->sw_octx, sw->sw_klen);
axf->Final(aalg, &ctx);
break;
}
/* Inject the authentication data */
if (outtype == CRYPTO_BUF_CONTIG)
bcopy(aalg, buf + crd->crd_inject, axf->authsize);
else
m_copyback((struct mbuf *) buf, crd->crd_inject, axf->authsize, aalg);
return 0;
}
/*
* Generate a new software session.
*/
int
swcr_newsession(u_int32_t *sid, struct cryptoini *cri)
{
struct swcr_data **swd;
struct auth_hash *axf;
struct enc_xform *txf;
u_int32_t i;
int k;
if ((sid == NULL) || (cri == NULL))
return EINVAL;
if (swcr_sessions)
for (i = 1; i < swcr_sesnum; i++)
if (swcr_sessions[i] == NULL)
break;
if ((swcr_sessions == NULL) || (i == swcr_sesnum))
{
if (swcr_sessions == NULL)
{
i = 1; /* We leave swcr_sessions[0] empty */
swcr_sesnum = CRYPTO_SW_SESSIONS;
}
else
swcr_sesnum *= 2;
swd = malloc(swcr_sesnum * sizeof(struct swcr_data *),
M_XDATA, M_NOWAIT);
if (swd == NULL)
{
/* Reset session number */
if (swcr_sesnum == CRYPTO_SW_SESSIONS)
swcr_sesnum = 0;
else
swcr_sesnum /= 2;
return ENOBUFS;
}
bzero(swd, swcr_sesnum * sizeof(struct swcr_data *));
/* Copy existing sessions */
if (swcr_sessions)
{
bcopy(swcr_sessions, swd,
(swcr_sesnum / 2) * sizeof(struct swcr_data *));
free(swcr_sessions, M_XDATA);
}
swcr_sessions = swd;
}
swd = &swcr_sessions[i];
*sid = i;
while (cri)
{
MALLOC(*swd, struct swcr_data *, sizeof(struct swcr_data), M_XDATA,
M_NOWAIT);
if (*swd == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
bzero(*swd, sizeof(struct swcr_data));
switch (cri->cri_alg)
{
case CRYPTO_DES_CBC:
txf = &enc_xform_des;
goto enccommon;
case CRYPTO_3DES_CBC:
txf = &enc_xform_3des;
goto enccommon;
case CRYPTO_BLF_CBC:
txf = &enc_xform_blf;
goto enccommon;
case CRYPTO_CAST_CBC:
txf = &enc_xform_cast5;
goto enccommon;
case CRYPTO_SKIPJACK_CBC:
txf = &enc_xform_skipjack;
goto enccommon;
case CRYPTO_RIJNDAEL128_CBC:
txf = &enc_xform_rijndael128;
goto enccommon;
enccommon:
txf->setkey(&((*swd)->sw_kschedule), cri->cri_key,
cri->cri_klen / 8);
(*swd)->sw_iv = malloc(txf->blocksize, M_XDATA, M_NOWAIT);
if ((*swd)->sw_iv == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
(*swd)->sw_exf = txf;
get_random_bytes((*swd)->sw_iv, txf->blocksize);
break;
case CRYPTO_MD5_HMAC96:
axf = &auth_hash_hmac_md5_96;
goto authcommon;
case CRYPTO_SHA1_HMAC96:
axf = &auth_hash_hmac_sha1_96;
goto authcommon;
case CRYPTO_RIPEMD160_HMAC96:
axf = &auth_hash_hmac_ripemd_160_96;
authcommon:
(*swd)->sw_ictx = malloc(axf->ctxsize, M_XDATA, M_NOWAIT);
if ((*swd)->sw_ictx == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
(*swd)->sw_octx = malloc(axf->ctxsize, M_XDATA, M_NOWAIT);
if ((*swd)->sw_octx == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
for (k = 0; k < cri->cri_klen / 8; k++)
cri->cri_key[k] ^= HMAC_IPAD_VAL;
axf->Init((*swd)->sw_ictx);
axf->Update((*swd)->sw_ictx, cri->cri_key,
cri->cri_klen / 8);
axf->Update((*swd)->sw_ictx, hmac_ipad_buffer,
HMAC_BLOCK_LEN - (cri->cri_klen / 8));
for (k = 0; k < cri->cri_klen / 8; k++)
cri->cri_key[k] ^= (HMAC_IPAD_VAL ^ HMAC_OPAD_VAL);
axf->Init((*swd)->sw_octx);
axf->Update((*swd)->sw_octx, cri->cri_key,
cri->cri_klen / 8);
axf->Update((*swd)->sw_octx, hmac_opad_buffer,
HMAC_BLOCK_LEN - (cri->cri_klen / 8));
for (k = 0; k < cri->cri_klen / 8; k++)
cri->cri_key[k] ^= HMAC_OPAD_VAL;
(*swd)->sw_axf = axf;
break;
case CRYPTO_MD5_KPDK:
axf = &auth_hash_key_md5;
goto auth2common;
case CRYPTO_SHA1_KPDK:
axf = &auth_hash_key_sha1;
auth2common:
(*swd)->sw_ictx = malloc(axf->ctxsize, M_XDATA, M_NOWAIT);
if ((*swd)->sw_ictx == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
/* Store the key so we can "append" it to the payload */
(*swd)->sw_octx = malloc(cri->cri_klen / 8, M_XDATA, M_NOWAIT);
if ((*swd)->sw_octx == NULL)
{
swcr_freesession(i);
return ENOBUFS;
}
(*swd)->sw_klen = cri->cri_klen / 8;
bcopy(cri->cri_key, (*swd)->sw_octx, cri->cri_klen / 8);
axf->Init((*swd)->sw_ictx);
axf->Update((*swd)->sw_ictx, cri->cri_key,
cri->cri_klen / 8);
axf->Final(NULL, (*swd)->sw_ictx);
(*swd)->sw_axf = axf;
break;
default:
swcr_freesession(i);
return EINVAL;
}
(*swd)->sw_alg = cri->cri_alg;
cri = cri->cri_next;
swd = &((*swd)->sw_next);
}
return 0;
}
/*
* Free a session.
*/
int
swcr_freesession(u_int64_t tid)
{
struct swcr_data *swd;
struct enc_xform *txf;
struct auth_hash *axf;
u_int32_t sid = ((u_int32_t) tid) & 0xffffffff;
if ((sid > swcr_sesnum) || (swcr_sessions == NULL) ||
(swcr_sessions[sid] == NULL))
return EINVAL;
/* Silently accept and return */
if (sid == 0)
return 0;
while ((swd = swcr_sessions[sid]) != NULL)
{
swcr_sessions[sid] = swd->sw_next;
switch (swd->sw_alg)
{
case CRYPTO_DES_CBC:
case CRYPTO_3DES_CBC:
case CRYPTO_BLF_CBC:
case CRYPTO_CAST_CBC:
case CRYPTO_SKIPJACK_CBC:
case CRYPTO_RIJNDAEL128_CBC:
txf = swd->sw_exf;
if (swd->sw_kschedule)
txf->zerokey(&(swd->sw_kschedule));
if (swd->sw_iv)
free(swd->sw_iv, M_XDATA);
break;
case CRYPTO_MD5_HMAC96:
case CRYPTO_SHA1_HMAC96:
case CRYPTO_RIPEMD160_HMAC96:
axf = swd->sw_axf;
if (swd->sw_ictx)
{
bzero(swd->sw_ictx, axf->ctxsize);
free(swd->sw_ictx, M_XDATA);
}
if (swd->sw_octx)
{
bzero(swd->sw_octx, axf->ctxsize);
free(swd->sw_octx, M_XDATA);
}
break;
case CRYPTO_MD5_KPDK:
case CRYPTO_SHA1_KPDK:
axf = swd->sw_axf;
if (swd->sw_ictx)
{
bzero(swd->sw_ictx, axf->ctxsize);
free(swd->sw_ictx, M_XDATA);
}
if (swd->sw_octx)
{
bzero(swd->sw_octx, swd->sw_klen);
free(swd->sw_octx, M_XDATA);
}
break;
}
FREE(swd, M_XDATA);
}
return 0;
}
/*
* Process a software request.
*/
int
swcr_process(struct cryptop *crp)
{
struct cryptodesc *crd;
struct swcr_data *sw;
u_int32_t lid;
u_int64_t nid;
int type;
/* Sanity check */
if (crp == NULL)
return EINVAL;
if ((crp->crp_desc == NULL) || (crp->crp_buf == NULL))
{
crp->crp_etype = EINVAL;
goto done;
}
lid = crp->crp_sid & 0xffffffff;
if ((lid >= swcr_sesnum) || (lid == 0) || (swcr_sessions[lid] == NULL))
{
crp->crp_etype = ENOENT;
goto done;
}
if (crp->crp_flags & CRYPTO_F_IMBUF)
type = CRYPTO_BUF_MBUF;
else
type = CRYPTO_BUF_CONTIG;
/* Go through crypto descriptors, processing as we go */
for (crd = crp->crp_desc; crd; crd = crd->crd_next)
{
/*
* Find the crypto context.
*
* XXX Note that the logic here prevents us from having
* XXX the same algorithm multiple times in a session
* XXX (or rather, we can but it won't give us the right
* XXX results). To do that, we'd need some way of differentiating
* XXX between the various instances of an algorithm (so we can
* XXX locate the correct crypto context).
*/
for (sw = swcr_sessions[lid];
sw && sw->sw_alg != crd->crd_alg;
sw = sw->sw_next)
;
/* No such context ? */
if (sw == NULL)
{
crp->crp_etype = EINVAL;
goto done;
}
switch (sw->sw_alg)
{
case CRYPTO_DES_CBC:
case CRYPTO_3DES_CBC:
case CRYPTO_BLF_CBC:
case CRYPTO_CAST_CBC:
case CRYPTO_SKIPJACK_CBC:
case CRYPTO_RIJNDAEL128_CBC:
if ((crp->crp_etype = swcr_encdec(crd, sw, crp->crp_buf,
type)) != 0)
goto done;
break;
case CRYPTO_MD5_HMAC96:
case CRYPTO_SHA1_HMAC96:
case CRYPTO_RIPEMD160_HMAC96:
case CRYPTO_MD5_KPDK:
case CRYPTO_SHA1_KPDK:
if ((crp->crp_etype = swcr_authcompute(crd, sw, crp->crp_buf,
type)) != 0)
goto done;
break;
default: /* Unknown/unsupported algorithm */
crp->crp_etype = EINVAL;
goto done;
}
}
done:
if (crp->crp_etype == ENOENT)
{
crypto_freesession(crp->crp_sid); /* Just in case */
/* Migrate session */
for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI)) == 0)
crp->crp_sid = nid;
}
crypto_done(crp);
return 0;
}
/*
* Initialize the driver, called from the kernel main().
*/
void
swcr_init(void)
{
swcr_id = crypto_get_driverid();
if (swcr_id >= 0)
{
crypto_register(swcr_id, CRYPTO_DES_CBC, swcr_newsession,
swcr_freesession, swcr_process);
crypto_register(swcr_id, CRYPTO_3DES_CBC, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_BLF_CBC, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_CAST_CBC, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_SKIPJACK_CBC, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_MD5_HMAC96, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_SHA1_HMAC96, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_RIPEMD160_HMAC96, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_MD5_KPDK, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_SHA1_KPDK, NULL, NULL, NULL);
crypto_register(swcr_id, CRYPTO_RIJNDAEL128_CBC, NULL, NULL, NULL);
return;
}
/* This should never happen */
panic("Software crypto device cannot initialize!");
}