crypto: poly1305-p10 - Glue code for optmized Poly1305 implementation for ppc64le

Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/arch/powerpc/crypto/poly1305-p10-glue.c b/arch/powerpc/crypto/poly1305-p10-glue.c
new file mode 100644 (file)
index 0000000..95dd708
--- /dev/null
+++ b/arch/powerpc/crypto/poly1305-p10-glue.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Poly1305 authenticator algorithm, RFC7539.
+ *
+ * Copyright 2023- IBM Corp. All rights reserved.
+ */
+
+#include <crypto/algapi.h>
+#include <linux/crypto.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/jump_label.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/poly1305.h>
+#include <crypto/internal/simd.h>
+#include <linux/cpufeature.h>
+#include <asm/unaligned.h>
+#include <asm/simd.h>
+#include <asm/switch_to.h>
+
+asmlinkage void poly1305_p10le_4blocks(void *h, const u8 *m, u32 mlen);
+asmlinkage void poly1305_64s(void *h, const u8 *m, u32 mlen, int highbit);
+asmlinkage void poly1305_emit_64(void *h, void *s, u8 *dst);
+
+static void vsx_begin(void)
+{
+       preempt_disable();
+       enable_kernel_vsx();
+}
+
+static void vsx_end(void)
+{
+       disable_kernel_vsx();
+       preempt_enable();
+}
+
+static int crypto_poly1305_p10_init(struct shash_desc *desc)
+{
+       struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
+
+       poly1305_core_init(&dctx->h);
+       dctx->buflen = 0;
+       dctx->rset = 0;
+       dctx->sset = false;
+
+       return 0;
+}
+
+static unsigned int crypto_poly1305_setdctxkey(struct poly1305_desc_ctx *dctx,
+                                              const u8 *inp, unsigned int len)
+{
+       unsigned int acc = 0;
+
+       if (unlikely(!dctx->sset)) {
+               if (!dctx->rset && len >= POLY1305_BLOCK_SIZE) {
+                       struct poly1305_core_key *key = &dctx->core_r;
+
+                       key->key.r64[0] = get_unaligned_le64(&inp[0]);
+                       key->key.r64[1] = get_unaligned_le64(&inp[8]);
+                       inp += POLY1305_BLOCK_SIZE;
+                       len -= POLY1305_BLOCK_SIZE;
+                       acc += POLY1305_BLOCK_SIZE;
+                       dctx->rset = 1;
+               }
+               if (len >= POLY1305_BLOCK_SIZE) {
+                       dctx->s[0] = get_unaligned_le32(&inp[0]);
+                       dctx->s[1] = get_unaligned_le32(&inp[4]);
+                       dctx->s[2] = get_unaligned_le32(&inp[8]);
+                       dctx->s[3] = get_unaligned_le32(&inp[12]);
+                       acc += POLY1305_BLOCK_SIZE;
+                       dctx->sset = true;
+               }
+       }
+       return acc;
+}
+
+static int crypto_poly1305_p10_update(struct shash_desc *desc,
+                                     const u8 *src, unsigned int srclen)
+{
+       struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
+       unsigned int bytes, used;
+
+       if (unlikely(dctx->buflen)) {
+               bytes = min(srclen, POLY1305_BLOCK_SIZE - dctx->buflen);
+               memcpy(dctx->buf + dctx->buflen, src, bytes);
+               src += bytes;
+               srclen -= bytes;
+               dctx->buflen += bytes;
+
+               if (dctx->buflen == POLY1305_BLOCK_SIZE) {
+                       if (likely(!crypto_poly1305_setdctxkey(dctx, dctx->buf,
+                                                              POLY1305_BLOCK_SIZE))) {
+                               vsx_begin();
+                               poly1305_64s(&dctx->h, dctx->buf,
+                                                 POLY1305_BLOCK_SIZE, 1);
+                               vsx_end();
+                       }
+                       dctx->buflen = 0;
+               }
+       }
+
+       if (likely(srclen >= POLY1305_BLOCK_SIZE)) {
+               bytes = round_down(srclen, POLY1305_BLOCK_SIZE);
+               used = crypto_poly1305_setdctxkey(dctx, src, bytes);
+               if (likely(used)) {
+                       srclen -= used;
+                       src += used;
+               }
+               if (crypto_simd_usable() && (srclen >= POLY1305_BLOCK_SIZE*4)) {
+                       vsx_begin();
+                       poly1305_p10le_4blocks(&dctx->h, src, srclen);
+                       vsx_end();
+                       src += srclen - (srclen % (POLY1305_BLOCK_SIZE * 4));
+                       srclen %= POLY1305_BLOCK_SIZE * 4;
+               }
+               while (srclen >= POLY1305_BLOCK_SIZE) {
+                       vsx_begin();
+                       poly1305_64s(&dctx->h, src, POLY1305_BLOCK_SIZE, 1);
+                       vsx_end();
+                       srclen -= POLY1305_BLOCK_SIZE;
+                       src += POLY1305_BLOCK_SIZE;
+               }
+       }
+
+       if (unlikely(srclen)) {
+               dctx->buflen = srclen;
+               memcpy(dctx->buf, src, srclen);
+       }
+
+       return 0;
+}
+
+static int crypto_poly1305_p10_final(struct shash_desc *desc, u8 *dst)
+{
+       struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
+
+       if (unlikely(!dctx->sset))
+               return -ENOKEY;
+
+       if ((dctx->buflen)) {
+               dctx->buf[dctx->buflen++] = 1;
+               memset(dctx->buf + dctx->buflen, 0,
+                      POLY1305_BLOCK_SIZE - dctx->buflen);
+               vsx_begin();
+               poly1305_64s(&dctx->h, dctx->buf, POLY1305_BLOCK_SIZE, 0);
+               vsx_end();
+               dctx->buflen = 0;
+       }
+
+       poly1305_emit_64(&dctx->h, &dctx->s, dst);
+       return 0;
+}
+
+static struct shash_alg poly1305_alg = {
+       .digestsize     = POLY1305_DIGEST_SIZE,
+       .init           = crypto_poly1305_p10_init,
+       .update         = crypto_poly1305_p10_update,
+       .final          = crypto_poly1305_p10_final,
+       .descsize       = sizeof(struct poly1305_desc_ctx),
+       .base           = {
+               .cra_name               = "poly1305",
+               .cra_driver_name        = "poly1305-p10",
+               .cra_priority           = 300,
+               .cra_blocksize          = POLY1305_BLOCK_SIZE,
+               .cra_module             = THIS_MODULE,
+       },
+};
+
+static int __init poly1305_p10_init(void)
+{
+       return crypto_register_shash(&poly1305_alg);
+}
+
+static void __exit poly1305_p10_exit(void)
+{
+       crypto_unregister_shash(&poly1305_alg);
+}
+
+module_cpu_feature_match(PPC_MODULE_FEATURE_P10, poly1305_p10_init);
+module_exit(poly1305_p10_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Danny Tsen <dtsen@linux.ibm.com>");
+MODULE_DESCRIPTION("Optimized Poly1305 for P10");
+MODULE_ALIAS_CRYPTO("poly1305");
+MODULE_ALIAS_CRYPTO("poly1305-p10");