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Diffstat (limited to 'arch/x86/crypto/poly1305_glue.c')
-rw-r--r--arch/x86/crypto/poly1305_glue.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/arch/x86/crypto/poly1305_glue.c b/arch/x86/crypto/poly1305_glue.c
new file mode 100644
index 000000000000..f7170d764f32
--- /dev/null
+++ b/arch/x86/crypto/poly1305_glue.c
@@ -0,0 +1,207 @@
+/*
+ * Poly1305 authenticator algorithm, RFC7539, SIMD glue code
+ *
+ * Copyright (C) 2015 Martin Willi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/internal/hash.h>
+#include <crypto/poly1305.h>
+#include <linux/crypto.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/fpu/api.h>
+#include <asm/simd.h>
+
+struct poly1305_simd_desc_ctx {
+ struct poly1305_desc_ctx base;
+ /* derived key u set? */
+ bool uset;
+#ifdef CONFIG_AS_AVX2
+ /* derived keys r^3, r^4 set? */
+ bool wset;
+#endif
+ /* derived Poly1305 key r^2 */
+ u32 u[5];
+ /* ... silently appended r^3 and r^4 when using AVX2 */
+};
+
+asmlinkage void poly1305_block_sse2(u32 *h, const u8 *src,
+ const u32 *r, unsigned int blocks);
+asmlinkage void poly1305_2block_sse2(u32 *h, const u8 *src, const u32 *r,
+ unsigned int blocks, const u32 *u);
+#ifdef CONFIG_AS_AVX2
+asmlinkage void poly1305_4block_avx2(u32 *h, const u8 *src, const u32 *r,
+ unsigned int blocks, const u32 *u);
+static bool poly1305_use_avx2;
+#endif
+
+static int poly1305_simd_init(struct shash_desc *desc)
+{
+ struct poly1305_simd_desc_ctx *sctx = shash_desc_ctx(desc);
+
+ sctx->uset = false;
+#ifdef CONFIG_AS_AVX2
+ sctx->wset = false;
+#endif
+
+ return crypto_poly1305_init(desc);
+}
+
+static void poly1305_simd_mult(u32 *a, const u32 *b)
+{
+ u8 m[POLY1305_BLOCK_SIZE];
+
+ memset(m, 0, sizeof(m));
+ /* The poly1305 block function adds a hi-bit to the accumulator which
+ * we don't need for key multiplication; compensate for it. */
+ a[4] -= 1 << 24;
+ poly1305_block_sse2(a, m, b, 1);
+}
+
+static unsigned int poly1305_simd_blocks(struct poly1305_desc_ctx *dctx,
+ const u8 *src, unsigned int srclen)
+{
+ struct poly1305_simd_desc_ctx *sctx;
+ unsigned int blocks, datalen;
+
+ BUILD_BUG_ON(offsetof(struct poly1305_simd_desc_ctx, base));
+ sctx = container_of(dctx, struct poly1305_simd_desc_ctx, base);
+
+ if (unlikely(!dctx->sset)) {
+ datalen = crypto_poly1305_setdesckey(dctx, src, srclen);
+ src += srclen - datalen;
+ srclen = datalen;
+ }
+
+#ifdef CONFIG_AS_AVX2
+ if (poly1305_use_avx2 && srclen >= POLY1305_BLOCK_SIZE * 4) {
+ if (unlikely(!sctx->wset)) {
+ if (!sctx->uset) {
+ memcpy(sctx->u, dctx->r, sizeof(sctx->u));
+ poly1305_simd_mult(sctx->u, dctx->r);
+ sctx->uset = true;
+ }
+ memcpy(sctx->u + 5, sctx->u, sizeof(sctx->u));
+ poly1305_simd_mult(sctx->u + 5, dctx->r);
+ memcpy(sctx->u + 10, sctx->u + 5, sizeof(sctx->u));
+ poly1305_simd_mult(sctx->u + 10, dctx->r);
+ sctx->wset = true;
+ }
+ blocks = srclen / (POLY1305_BLOCK_SIZE * 4);
+ poly1305_4block_avx2(dctx->h, src, dctx->r, blocks, sctx->u);
+ src += POLY1305_BLOCK_SIZE * 4 * blocks;
+ srclen -= POLY1305_BLOCK_SIZE * 4 * blocks;
+ }
+#endif
+ if (likely(srclen >= POLY1305_BLOCK_SIZE * 2)) {
+ if (unlikely(!sctx->uset)) {
+ memcpy(sctx->u, dctx->r, sizeof(sctx->u));
+ poly1305_simd_mult(sctx->u, dctx->r);
+ sctx->uset = true;
+ }
+ blocks = srclen / (POLY1305_BLOCK_SIZE * 2);
+ poly1305_2block_sse2(dctx->h, src, dctx->r, blocks, sctx->u);
+ src += POLY1305_BLOCK_SIZE * 2 * blocks;
+ srclen -= POLY1305_BLOCK_SIZE * 2 * blocks;
+ }
+ if (srclen >= POLY1305_BLOCK_SIZE) {
+ poly1305_block_sse2(dctx->h, src, dctx->r, 1);
+ srclen -= POLY1305_BLOCK_SIZE;
+ }
+ return srclen;
+}
+
+static int poly1305_simd_update(struct shash_desc *desc,
+ const u8 *src, unsigned int srclen)
+{
+ struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
+ unsigned int bytes;
+
+ /* kernel_fpu_begin/end is costly, use fallback for small updates */
+ if (srclen <= 288 || !may_use_simd())
+ return crypto_poly1305_update(desc, src, srclen);
+
+ kernel_fpu_begin();
+
+ 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) {
+ poly1305_simd_blocks(dctx, dctx->buf,
+ POLY1305_BLOCK_SIZE);
+ dctx->buflen = 0;
+ }
+ }
+
+ if (likely(srclen >= POLY1305_BLOCK_SIZE)) {
+ bytes = poly1305_simd_blocks(dctx, src, srclen);
+ src += srclen - bytes;
+ srclen = bytes;
+ }
+
+ kernel_fpu_end();
+
+ if (unlikely(srclen)) {
+ dctx->buflen = srclen;
+ memcpy(dctx->buf, src, srclen);
+ }
+
+ return 0;
+}
+
+static struct shash_alg alg = {
+ .digestsize = POLY1305_DIGEST_SIZE,
+ .init = poly1305_simd_init,
+ .update = poly1305_simd_update,
+ .final = crypto_poly1305_final,
+ .setkey = crypto_poly1305_setkey,
+ .descsize = sizeof(struct poly1305_simd_desc_ctx),
+ .base = {
+ .cra_name = "poly1305",
+ .cra_driver_name = "poly1305-simd",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_SHASH,
+ .cra_alignmask = sizeof(u32) - 1,
+ .cra_blocksize = POLY1305_BLOCK_SIZE,
+ .cra_module = THIS_MODULE,
+ },
+};
+
+static int __init poly1305_simd_mod_init(void)
+{
+ if (!cpu_has_xmm2)
+ return -ENODEV;
+
+#ifdef CONFIG_AS_AVX2
+ poly1305_use_avx2 = cpu_has_avx && cpu_has_avx2 &&
+ cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL);
+ alg.descsize = sizeof(struct poly1305_simd_desc_ctx);
+ if (poly1305_use_avx2)
+ alg.descsize += 10 * sizeof(u32);
+#endif
+ return crypto_register_shash(&alg);
+}
+
+static void __exit poly1305_simd_mod_exit(void)
+{
+ crypto_unregister_shash(&alg);
+}
+
+module_init(poly1305_simd_mod_init);
+module_exit(poly1305_simd_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
+MODULE_DESCRIPTION("Poly1305 authenticator");
+MODULE_ALIAS_CRYPTO("poly1305");
+MODULE_ALIAS_CRYPTO("poly1305-simd");