Author: jhb
Date: Fri Jun 12 23:10:30 2020
New Revision: 362135
URL: https://svnweb.freebsd.org/changeset/base/362135
Log:
Various optimizations to software AES-CCM and AES-GCM.
- Make use of cursors to avoid data copies for AES-CCM and AES-GCM.
Pass pointers into the request's input and/or output buffers
directly to the Update, encrypt, and decrypt hooks rather than
always copying all data into a temporary block buffer on the stack.
- Move handling for partial final blocks out of the main loop.
This removes branches from the main loop and permits using
encrypt/decrypt_last which avoids a memset to clear the rest of the
block on the stack.
- Shrink the on-stack buffers to assume AES block sizes and CCM/GCM
tag lengths.
- For AAD data, pass larger chunks to axf->Update. CCM can take each
AAD segment in a single call. GMAC can take multiple blocks at a
time.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D25058
Modified:
head/sys/opencrypto/cryptosoft.c
Modified: head/sys/opencrypto/cryptosoft.c
==============================================================================
--- head/sys/opencrypto/cryptosoft.c Fri Jun 12 23:02:34 2020
(r362134)
+++ head/sys/opencrypto/cryptosoft.c Fri Jun 12 23:10:30 2020
(r362135)
@@ -107,8 +107,8 @@ swcr_encdec(struct swcr_session *ses, struct cryptop *
struct enc_xform *exf;
int i, blks, inlen, ivlen, outlen, resid;
struct crypto_buffer_cursor cc_in, cc_out;
- const char *inblk;
- char *outblk;
+ const unsigned char *inblk;
+ unsigned char *outblk;
int error;
bool encrypting;
@@ -404,11 +404,12 @@ CTASSERT(INT_MAX <= (uint64_t)-1); /* GCM:
associated
static int
swcr_gmac(struct swcr_session *ses, struct cryptop *crp)
{
- uint32_t blkbuf[howmany(EALG_MAX_BLOCK_LEN, sizeof(uint32_t))];
+ uint32_t blkbuf[howmany(AES_BLOCK_LEN, sizeof(uint32_t))];
u_char *blk = (u_char *)blkbuf;
- u_char aalg[AALG_MAX_RESULT_LEN];
- u_char iv[EALG_MAX_BLOCK_LEN];
+ u_char tag[GMAC_DIGEST_LEN];
+ u_char iv[AES_BLOCK_LEN];
struct crypto_buffer_cursor cc;
+ const u_char *inblk;
union authctx ctx;
struct swcr_auth *swa;
struct auth_hash *axf;
@@ -419,7 +420,9 @@ swcr_gmac(struct swcr_session *ses, struct cryptop *cr
axf = swa->sw_axf;
bcopy(swa->sw_ictx, &ctx, axf->ctxsize);
- blksz = axf->blocksize;
+ blksz = GMAC_BLOCK_LEN;
+ KASSERT(axf->blocksize == blksz, ("%s: axf block size mismatch",
+ __func__));
/* Initialize the IV */
ivlen = AES_GCM_IV_LEN;
@@ -428,37 +431,49 @@ swcr_gmac(struct swcr_session *ses, struct cryptop *cr
axf->Reinit(&ctx, iv, ivlen);
crypto_cursor_init(&cc, &crp->crp_buf);
crypto_cursor_advance(&cc, crp->crp_payload_start);
- for (resid = crp->crp_payload_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- crypto_cursor_copydata(&cc, len, blk);
- bzero(blk + len, blksz - len);
+ for (resid = crp->crp_payload_length; resid >= blksz; resid -= len) {
+ len = crypto_cursor_seglen(&cc);
+ if (len >= blksz) {
+ inblk = crypto_cursor_segbase(&cc);
+ len = rounddown(MIN(len, resid), blksz);
+ crypto_cursor_advance(&cc, len);
+ } else {
+ len = blksz;
+ crypto_cursor_copydata(&cc, len, blk);
+ inblk = blk;
+ }
+ axf->Update(&ctx, inblk, len);
+ }
+ if (resid > 0) {
+ memset(blk, 0, blksz);
+ crypto_cursor_copydata(&cc, resid, blk);
axf->Update(&ctx, blk, blksz);
}
/* length block */
- bzero(blk, blksz);
+ memset(blk, 0, blksz);
blkp = (uint32_t *)blk + 1;
*blkp = htobe32(crp->crp_payload_length * 8);
axf->Update(&ctx, blk, blksz);
/* Finalize MAC */
- axf->Final(aalg, &ctx);
+ axf->Final(tag, &ctx);
error = 0;
if (crp->crp_op & CRYPTO_OP_VERIFY_DIGEST) {
- u_char uaalg[AALG_MAX_RESULT_LEN];
+ u_char tag2[GMAC_DIGEST_LEN];
crypto_copydata(crp, crp->crp_digest_start, swa->sw_mlen,
- uaalg);
- if (timingsafe_bcmp(aalg, uaalg, swa->sw_mlen) != 0)
+ tag2);
+ if (timingsafe_bcmp(tag, tag2, swa->sw_mlen) != 0)
error = EBADMSG;
- explicit_bzero(uaalg, sizeof(uaalg));
+ explicit_bzero(tag2, sizeof(tag2));
} else {
/* Inject the authentication data */
- crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, aalg);
+ crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, tag);
}
explicit_bzero(blkbuf, sizeof(blkbuf));
- explicit_bzero(aalg, sizeof(aalg));
+ explicit_bzero(tag, sizeof(tag));
explicit_bzero(iv, sizeof(iv));
return (error);
}
@@ -466,11 +481,13 @@ swcr_gmac(struct swcr_session *ses, struct cryptop *cr
static int
swcr_gcm(struct swcr_session *ses, struct cryptop *crp)
{
- uint32_t blkbuf[howmany(EALG_MAX_BLOCK_LEN, sizeof(uint32_t))];
+ uint32_t blkbuf[howmany(AES_BLOCK_LEN, sizeof(uint32_t))];
u_char *blk = (u_char *)blkbuf;
- u_char aalg[AALG_MAX_RESULT_LEN];
- u_char iv[EALG_MAX_BLOCK_LEN];
+ u_char tag[GMAC_DIGEST_LEN];
+ u_char iv[AES_BLOCK_LEN];
struct crypto_buffer_cursor cc_in, cc_out;
+ const u_char *inblk;
+ u_char *outblk;
union authctx ctx;
struct swcr_auth *swa;
struct swcr_encdec *swe;
@@ -483,7 +500,9 @@ swcr_gcm(struct swcr_session *ses, struct cryptop *crp
axf = swa->sw_axf;
bcopy(swa->sw_ictx, &ctx, axf->ctxsize);
- blksz = axf->blocksize;
+ blksz = GMAC_BLOCK_LEN;
+ KASSERT(axf->blocksize == blksz, ("%s: axf block size mismatch",
+ __func__));
swe = &ses->swcr_encdec;
exf = swe->sw_exf;
@@ -503,10 +522,22 @@ swcr_gcm(struct swcr_session *ses, struct cryptop *crp
/* Supply MAC with AAD */
crypto_cursor_init(&cc_in, &crp->crp_buf);
crypto_cursor_advance(&cc_in, crp->crp_aad_start);
- for (resid = crp->crp_aad_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
- bzero(blk + len, blksz - len);
+ for (resid = crp->crp_aad_length; resid >= blksz; resid -= len) {
+ len = crypto_cursor_seglen(&cc_in);
+ if (len >= blksz) {
+ inblk = crypto_cursor_segbase(&cc_in);
+ len = rounddown(MIN(len, resid), blksz);
+ crypto_cursor_advance(&cc_in, len);
+ } else {
+ len = blksz;
+ crypto_cursor_copydata(&cc_in, len, blk);
+ inblk = blk;
+ }
+ axf->Update(&ctx, inblk, len);
+ }
+ if (resid > 0) {
+ memset(blk, 0, blksz);
+ crypto_cursor_copydata(&cc_in, resid, blk);
axf->Update(&ctx, blk, blksz);
}
@@ -520,22 +551,40 @@ swcr_gcm(struct swcr_session *ses, struct cryptop *crp
crypto_cursor_advance(&cc_out, crp->crp_payload_output_start);
} else
cc_out = cc_in;
- for (resid = crp->crp_payload_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- if (len < blksz)
- bzero(blk, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
+ for (resid = crp->crp_payload_length; resid >= blksz; resid -= blksz) {
+ if (crypto_cursor_seglen(&cc_in) < blksz) {
+ crypto_cursor_copydata(&cc_in, blksz, blk);
+ inblk = blk;
+ } else {
+ inblk = crypto_cursor_segbase(&cc_in);
+ crypto_cursor_advance(&cc_in, blksz);
+ }
if (CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
- exf->encrypt(swe->sw_kschedule, blk, blk);
- axf->Update(&ctx, blk, len);
- crypto_cursor_copyback(&cc_out, len, blk);
+ if (crypto_cursor_seglen(&cc_out) < blksz)
+ outblk = blk;
+ else
+ outblk = crypto_cursor_segbase(&cc_out);
+ exf->encrypt(swe->sw_kschedule, inblk, outblk);
+ axf->Update(&ctx, outblk, blksz);
+ if (outblk == blk)
+ crypto_cursor_copyback(&cc_out, blksz, blk);
+ else
+ crypto_cursor_advance(&cc_out, blksz);
} else {
- axf->Update(&ctx, blk, len);
+ axf->Update(&ctx, inblk, blksz);
}
}
+ if (resid > 0) {
+ crypto_cursor_copydata(&cc_in, resid, blk);
+ if (CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
+ exf->encrypt_last(swe->sw_kschedule, blk, blk, resid);
+ crypto_cursor_copyback(&cc_out, resid, blk);
+ }
+ axf->Update(&ctx, blk, resid);
+ }
/* length block */
- bzero(blk, blksz);
+ memset(blk, 0, blksz);
blkp = (uint32_t *)blk + 1;
*blkp = htobe32(crp->crp_aad_length * 8);
blkp = (uint32_t *)blk + 3;
@@ -543,18 +592,17 @@ swcr_gcm(struct swcr_session *ses, struct cryptop *crp
axf->Update(&ctx, blk, blksz);
/* Finalize MAC */
- axf->Final(aalg, &ctx);
+ axf->Final(tag, &ctx);
/* Validate tag */
error = 0;
if (!CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
- u_char uaalg[AALG_MAX_RESULT_LEN];
+ u_char tag2[GMAC_DIGEST_LEN];
- crypto_copydata(crp, crp->crp_digest_start, swa->sw_mlen,
- uaalg);
+ crypto_copydata(crp, crp->crp_digest_start, swa->sw_mlen, tag2);
- r = timingsafe_bcmp(aalg, uaalg, swa->sw_mlen);
- explicit_bzero(uaalg, sizeof(uaalg));
+ r = timingsafe_bcmp(tag, tag2, swa->sw_mlen);
+ explicit_bzero(tag2, sizeof(tag2));
if (r != 0) {
error = EBADMSG;
goto out;
@@ -563,24 +611,38 @@ swcr_gcm(struct swcr_session *ses, struct cryptop *crp
/* tag matches, decrypt data */
crypto_cursor_init(&cc_in, &crp->crp_buf);
crypto_cursor_advance(&cc_in, crp->crp_payload_start);
- for (resid = crp->crp_payload_length; resid > 0;
- resid -= len) {
- len = MIN(resid, blksz);
- if (len < blksz)
- bzero(blk, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
- exf->decrypt(swe->sw_kschedule, blk, blk);
- crypto_cursor_copyback(&cc_out, len, blk);
+ for (resid = crp->crp_payload_length; resid > blksz;
+ resid -= blksz) {
+ if (crypto_cursor_seglen(&cc_in) < blksz) {
+ crypto_cursor_copydata(&cc_in, blksz, blk);
+ inblk = blk;
+ } else {
+ inblk = crypto_cursor_segbase(&cc_in);
+ crypto_cursor_advance(&cc_in, blksz);
+ }
+ if (crypto_cursor_seglen(&cc_out) < blksz)
+ outblk = blk;
+ else
+ outblk = crypto_cursor_segbase(&cc_out);
+ exf->decrypt(swe->sw_kschedule, inblk, outblk);
+ if (outblk == blk)
+ crypto_cursor_copyback(&cc_out, blksz, blk);
+ else
+ crypto_cursor_advance(&cc_out, blksz);
}
+ if (resid > 0) {
+ crypto_cursor_copydata(&cc_in, resid, blk);
+ exf->decrypt_last(swe->sw_kschedule, blk, blk, resid);
+ crypto_cursor_copyback(&cc_out, resid, blk);
+ }
} else {
/* Inject the authentication data */
- crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen,
- aalg);
+ crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, tag);
}
out:
explicit_bzero(blkbuf, sizeof(blkbuf));
- explicit_bzero(aalg, sizeof(aalg));
+ explicit_bzero(tag, sizeof(tag));
explicit_bzero(iv, sizeof(iv));
return (error);
@@ -589,21 +651,17 @@ out:
static int
swcr_ccm_cbc_mac(struct swcr_session *ses, struct cryptop *crp)
{
- uint32_t blkbuf[howmany(EALG_MAX_BLOCK_LEN, sizeof(uint32_t))];
- u_char *blk = (u_char *)blkbuf;
- u_char aalg[AALG_MAX_RESULT_LEN];
- u_char iv[EALG_MAX_BLOCK_LEN];
- struct crypto_buffer_cursor cc;
+ u_char tag[AES_CBC_MAC_HASH_LEN];
+ u_char iv[AES_BLOCK_LEN];
union authctx ctx;
struct swcr_auth *swa;
struct auth_hash *axf;
- int blksz, error, ivlen, len, resid;
+ int error, ivlen;
swa = &ses->swcr_auth;
axf = swa->sw_axf;
bcopy(swa->sw_ictx, &ctx, axf->ctxsize);
- blksz = axf->blocksize;
/* Initialize the IV */
ivlen = AES_CCM_IV_LEN;
@@ -617,33 +675,27 @@ swcr_ccm_cbc_mac(struct swcr_session *ses, struct cryp
ctx.aes_cbc_mac_ctx.cryptDataLength = 0;
axf->Reinit(&ctx, iv, ivlen);
- crypto_cursor_init(&cc, &crp->crp_buf);
- crypto_cursor_advance(&cc, crp->crp_aad_start);
- for (resid = crp->crp_payload_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- crypto_cursor_copydata(&cc, len, blk);
- bzero(blk + len, blksz - len);
- axf->Update(&ctx, blk, blksz);
- }
+ error = crypto_apply(crp, crp->crp_payload_start,
+ crp->crp_payload_length, axf->Update, &ctx);
+ if (error)
+ return (error);
/* Finalize MAC */
- axf->Final(aalg, &ctx);
+ axf->Final(tag, &ctx);
- error = 0;
if (crp->crp_op & CRYPTO_OP_VERIFY_DIGEST) {
- u_char uaalg[AALG_MAX_RESULT_LEN];
+ u_char tag2[AES_CBC_MAC_HASH_LEN];
crypto_copydata(crp, crp->crp_digest_start, swa->sw_mlen,
- uaalg);
- if (timingsafe_bcmp(aalg, uaalg, swa->sw_mlen) != 0)
+ tag2);
+ if (timingsafe_bcmp(tag, tag2, swa->sw_mlen) != 0)
error = EBADMSG;
- explicit_bzero(uaalg, sizeof(uaalg));
+ explicit_bzero(tag2, sizeof(tag));
} else {
/* Inject the authentication data */
- crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, aalg);
+ crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, tag);
}
- explicit_bzero(blkbuf, sizeof(blkbuf));
- explicit_bzero(aalg, sizeof(aalg));
+ explicit_bzero(tag, sizeof(tag));
explicit_bzero(iv, sizeof(iv));
return (error);
}
@@ -651,23 +703,27 @@ swcr_ccm_cbc_mac(struct swcr_session *ses, struct cryp
static int
swcr_ccm(struct swcr_session *ses, struct cryptop *crp)
{
- uint32_t blkbuf[howmany(EALG_MAX_BLOCK_LEN, sizeof(uint32_t))];
+ uint32_t blkbuf[howmany(AES_BLOCK_LEN, sizeof(uint32_t))];
u_char *blk = (u_char *)blkbuf;
- u_char aalg[AALG_MAX_RESULT_LEN];
- u_char iv[EALG_MAX_BLOCK_LEN];
+ u_char tag[AES_CBC_MAC_HASH_LEN];
+ u_char iv[AES_BLOCK_LEN];
struct crypto_buffer_cursor cc_in, cc_out;
+ const u_char *inblk;
+ u_char *outblk;
union authctx ctx;
struct swcr_auth *swa;
struct swcr_encdec *swe;
struct auth_hash *axf;
struct enc_xform *exf;
- int blksz, error, ivlen, len, r, resid;
+ int blksz, error, ivlen, r, resid;
swa = &ses->swcr_auth;
axf = swa->sw_axf;
bcopy(swa->sw_ictx, &ctx, axf->ctxsize);
- blksz = axf->blocksize;
+ blksz = AES_BLOCK_LEN;
+ KASSERT(axf->blocksize == blksz, ("%s: axf block size mismatch",
+ __func__));
swe = &ses->swcr_encdec;
exf = swe->sw_exf;
@@ -692,14 +748,10 @@ swcr_ccm(struct swcr_session *ses, struct cryptop *crp
axf->Reinit(&ctx, iv, ivlen);
/* Supply MAC with AAD */
- crypto_cursor_init(&cc_in, &crp->crp_buf);
- crypto_cursor_advance(&cc_in, crp->crp_aad_start);
- for (resid = crp->crp_aad_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
- bzero(blk + len, blksz - len);
- axf->Update(&ctx, blk, blksz);
- }
+ error = crypto_apply(crp, crp->crp_aad_start, crp->crp_aad_length,
+ axf->Update, &ctx);
+ if (error)
+ return (error);
exf->reinit(swe->sw_kschedule, iv);
@@ -711,69 +763,104 @@ swcr_ccm(struct swcr_session *ses, struct cryptop *crp
crypto_cursor_advance(&cc_out, crp->crp_payload_output_start);
} else
cc_out = cc_in;
- for (resid = crp->crp_payload_length; resid > 0; resid -= len) {
- len = MIN(resid, blksz);
- if (len < blksz)
- bzero(blk, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
+ for (resid = crp->crp_payload_length; resid >= blksz; resid -= blksz) {
+ if (crypto_cursor_seglen(&cc_in) < blksz) {
+ crypto_cursor_copydata(&cc_in, blksz, blk);
+ inblk = blk;
+ } else {
+ inblk = crypto_cursor_segbase(&cc_in);
+ crypto_cursor_advance(&cc_in, blksz);
+ }
if (CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
- axf->Update(&ctx, blk, len);
- exf->encrypt(swe->sw_kschedule, blk, blk);
- crypto_cursor_copyback(&cc_out, len, blk);
+ if (crypto_cursor_seglen(&cc_out) < blksz)
+ outblk = blk;
+ else
+ outblk = crypto_cursor_segbase(&cc_out);
+ axf->Update(&ctx, inblk, blksz);
+ exf->encrypt(swe->sw_kschedule, inblk, outblk);
+ if (outblk == blk)
+ crypto_cursor_copyback(&cc_out, blksz, blk);
+ else
+ crypto_cursor_advance(&cc_out, blksz);
} else {
/*
* One of the problems with CCM+CBC is that
* the authentication is done on the
- * unecncrypted data. As a result, we have to
+ * unencrypted data. As a result, we have to
* decrypt the data twice: once to generate
* the tag and a second time after the tag is
* verified.
*/
- exf->decrypt(swe->sw_kschedule, blk, blk);
- axf->Update(&ctx, blk, len);
+ exf->decrypt(swe->sw_kschedule, inblk, blk);
+ axf->Update(&ctx, blk, blksz);
}
}
+ if (resid > 0) {
+ crypto_cursor_copydata(&cc_in, resid, blk);
+ if (CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
+ axf->Update(&ctx, blk, resid);
+ exf->encrypt_last(swe->sw_kschedule, blk, blk, resid);
+ crypto_cursor_copyback(&cc_out, resid, blk);
+ } else {
+ exf->decrypt_last(swe->sw_kschedule, blk, blk, resid);
+ axf->Update(&ctx, blk, resid);
+ }
+ }
/* Finalize MAC */
- axf->Final(aalg, &ctx);
+ axf->Final(tag, &ctx);
/* Validate tag */
error = 0;
if (!CRYPTO_OP_IS_ENCRYPT(crp->crp_op)) {
- u_char uaalg[AALG_MAX_RESULT_LEN];
+ u_char tag2[AES_CBC_MAC_HASH_LEN];
crypto_copydata(crp, crp->crp_digest_start, swa->sw_mlen,
- uaalg);
+ tag2);
- r = timingsafe_bcmp(aalg, uaalg, swa->sw_mlen);
- explicit_bzero(uaalg, sizeof(uaalg));
+ r = timingsafe_bcmp(tag, tag2, swa->sw_mlen);
+ explicit_bzero(tag2, sizeof(tag2));
if (r != 0) {
error = EBADMSG;
goto out;
}
-
+
/* tag matches, decrypt data */
exf->reinit(swe->sw_kschedule, iv);
crypto_cursor_init(&cc_in, &crp->crp_buf);
crypto_cursor_advance(&cc_in, crp->crp_payload_start);
- for (resid = crp->crp_payload_length; resid > 0;
- resid -= len) {
- len = MIN(resid, blksz);
- if (len < blksz)
- bzero(blk, blksz);
- crypto_cursor_copydata(&cc_in, len, blk);
- exf->decrypt(swe->sw_kschedule, blk, blk);
- crypto_cursor_copyback(&cc_out, len, blk);
+ for (resid = crp->crp_payload_length; resid > blksz;
+ resid -= blksz) {
+ if (crypto_cursor_seglen(&cc_in) < blksz) {
+ crypto_cursor_copydata(&cc_in, blksz, blk);
+ inblk = blk;
+ } else {
+ inblk = crypto_cursor_segbase(&cc_in);
+ crypto_cursor_advance(&cc_in, blksz);
+ }
+ if (crypto_cursor_seglen(&cc_out) < blksz)
+ outblk = blk;
+ else
+ outblk = crypto_cursor_segbase(&cc_out);
+ exf->decrypt(swe->sw_kschedule, inblk, outblk);
+ if (outblk == blk)
+ crypto_cursor_copyback(&cc_out, blksz, blk);
+ else
+ crypto_cursor_advance(&cc_out, blksz);
}
+ if (resid > 0) {
+ crypto_cursor_copydata(&cc_in, resid, blk);
+ exf->decrypt_last(swe->sw_kschedule, blk, blk, resid);
+ crypto_cursor_copyback(&cc_out, resid, blk);
+ }
} else {
/* Inject the authentication data */
- crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen,
- aalg);
+ crypto_copyback(crp, crp->crp_digest_start, swa->sw_mlen, tag);
}
out:
explicit_bzero(blkbuf, sizeof(blkbuf));
- explicit_bzero(aalg, sizeof(aalg));
+ explicit_bzero(tag, sizeof(tag));
explicit_bzero(iv, sizeof(iv));
return (error);
}
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