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-rw-r--r--comm/third_party/libgcrypt/cipher/salsa20.c600
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diff --git a/comm/third_party/libgcrypt/cipher/salsa20.c b/comm/third_party/libgcrypt/cipher/salsa20.c
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+++ b/comm/third_party/libgcrypt/cipher/salsa20.c
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+/* salsa20.c - Bernstein's Salsa20 cipher
+ * Copyright (C) 2012 Simon Josefsson, Niels Möller
+ * Copyright (C) 2013 g10 Code GmbH
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser general Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * For a description of the algorithm, see:
+ * http://cr.yp.to/snuffle/spec.pdf
+ * http://cr.yp.to/snuffle/design.pdf
+ */
+
+/* The code is based on the code in Nettle
+ (git commit id 9d2d8ddaee35b91a4e1a32ae77cba04bea3480e7)
+ which in turn is based on
+ salsa20-ref.c version 20051118
+ D. J. Bernstein
+ Public domain.
+*/
+
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "types.h"
+#include "g10lib.h"
+#include "cipher.h"
+#include "bufhelp.h"
+#include "cipher-internal.h"
+
+
+/* USE_AMD64 indicates whether to compile with AMD64 code. */
+#undef USE_AMD64
+#if defined(__x86_64__) && (defined(HAVE_COMPATIBLE_GCC_AMD64_PLATFORM_AS) || \
+ defined(HAVE_COMPATIBLE_GCC_WIN64_PLATFORM_AS))
+# define USE_AMD64 1
+#endif
+
+/* USE_ARM_NEON_ASM indicates whether to enable ARM NEON assembly code. */
+#undef USE_ARM_NEON_ASM
+#ifdef ENABLE_NEON_SUPPORT
+# if defined(HAVE_ARM_ARCH_V6) && defined(__ARMEL__) \
+ && defined(HAVE_COMPATIBLE_GCC_ARM_PLATFORM_AS) \
+ && defined(HAVE_GCC_INLINE_ASM_NEON)
+# define USE_ARM_NEON_ASM 1
+# endif
+#endif /*ENABLE_NEON_SUPPORT*/
+
+
+#define SALSA20_MIN_KEY_SIZE 16 /* Bytes. */
+#define SALSA20_MAX_KEY_SIZE 32 /* Bytes. */
+#define SALSA20_BLOCK_SIZE 64 /* Bytes. */
+#define SALSA20_IV_SIZE 8 /* Bytes. */
+#define SALSA20_INPUT_LENGTH 16 /* Bytes. */
+
+/* Number of rounds. The standard uses 20 rounds. In any case the
+ number of rounds must be even. */
+#define SALSA20_ROUNDS 20
+#define SALSA20R12_ROUNDS 12
+
+
+struct SALSA20_context_s;
+
+typedef unsigned int (*salsa20_core_t) (u32 *dst, struct SALSA20_context_s *ctx,
+ unsigned int rounds);
+typedef void (* salsa20_keysetup_t)(struct SALSA20_context_s *ctx,
+ const byte *key, int keylen);
+typedef void (* salsa20_ivsetup_t)(struct SALSA20_context_s *ctx,
+ const byte *iv);
+
+typedef struct SALSA20_context_s
+{
+ /* Indices 1-4 and 11-14 holds the key (two identical copies for the
+ shorter key size), indices 0, 5, 10, 15 are constant, indices 6, 7
+ are the IV, and indices 8, 9 are the block counter:
+
+ C K K K
+ K C I I
+ B B C K
+ K K K C
+ */
+ u32 input[SALSA20_INPUT_LENGTH];
+ u32 pad[SALSA20_INPUT_LENGTH];
+ unsigned int unused; /* bytes in the pad. */
+#ifdef USE_ARM_NEON_ASM
+ int use_neon;
+#endif
+ salsa20_keysetup_t keysetup;
+ salsa20_ivsetup_t ivsetup;
+ salsa20_core_t core;
+} SALSA20_context_t;
+
+
+/* The masking of the right shift is needed to allow n == 0 (using
+ just 32 - n and 64 - n results in undefined behaviour). Most uses
+ of these macros use a constant and non-zero rotation count. */
+#define ROTL32(n,x) (((x)<<(n)) | ((x)>>((-(n)&31))))
+
+
+#define LE_SWAP32(v) le_bswap32(v)
+
+#define LE_READ_UINT32(p) buf_get_le32(p)
+
+
+static void salsa20_setiv (void *context, const byte *iv, size_t ivlen);
+static const char *selftest (void);
+
+
+#ifdef USE_AMD64
+
+/* Assembly implementations use SystemV ABI, ABI conversion and additional
+ * stack to store XMM6-XMM15 needed on Win64. */
+#ifdef HAVE_COMPATIBLE_GCC_WIN64_PLATFORM_AS
+# define ASM_FUNC_ABI __attribute__((sysv_abi))
+# define ASM_EXTRA_STACK (10 * 16)
+#else
+# define ASM_FUNC_ABI
+# define ASM_EXTRA_STACK 0
+#endif
+
+/* AMD64 assembly implementations of Salsa20. */
+void _gcry_salsa20_amd64_keysetup(u32 *ctxinput, const void *key, int keybits)
+ ASM_FUNC_ABI;
+void _gcry_salsa20_amd64_ivsetup(u32 *ctxinput, const void *iv)
+ ASM_FUNC_ABI;
+unsigned int
+_gcry_salsa20_amd64_encrypt_blocks(u32 *ctxinput, const void *src, void *dst,
+ size_t len, int rounds) ASM_FUNC_ABI;
+
+static void
+salsa20_keysetup(SALSA20_context_t *ctx, const byte *key, int keylen)
+{
+ _gcry_salsa20_amd64_keysetup(ctx->input, key, keylen * 8);
+}
+
+static void
+salsa20_ivsetup(SALSA20_context_t *ctx, const byte *iv)
+{
+ _gcry_salsa20_amd64_ivsetup(ctx->input, iv);
+}
+
+static unsigned int
+salsa20_core (u32 *dst, SALSA20_context_t *ctx, unsigned int rounds)
+{
+ memset(dst, 0, SALSA20_BLOCK_SIZE);
+ return _gcry_salsa20_amd64_encrypt_blocks(ctx->input, dst, dst, 1, rounds)
+ + ASM_EXTRA_STACK;
+}
+
+#else /* USE_AMD64 */
+
+
+
+#if 0
+# define SALSA20_CORE_DEBUG(i) do { \
+ unsigned debug_j; \
+ for (debug_j = 0; debug_j < 16; debug_j++) \
+ { \
+ if (debug_j == 0) \
+ fprintf(stderr, "%2d:", (i)); \
+ else if (debug_j % 4 == 0) \
+ fprintf(stderr, "\n "); \
+ fprintf(stderr, " %8x", pad[debug_j]); \
+ } \
+ fprintf(stderr, "\n"); \
+ } while (0)
+#else
+# define SALSA20_CORE_DEBUG(i)
+#endif
+
+#define QROUND(x0, x1, x2, x3) \
+ do { \
+ x1 ^= ROTL32 ( 7, x0 + x3); \
+ x2 ^= ROTL32 ( 9, x1 + x0); \
+ x3 ^= ROTL32 (13, x2 + x1); \
+ x0 ^= ROTL32 (18, x3 + x2); \
+ } while(0)
+
+static unsigned int
+salsa20_core (u32 *dst, SALSA20_context_t *ctx, unsigned rounds)
+{
+ u32 pad[SALSA20_INPUT_LENGTH], *src = ctx->input;
+ unsigned int i;
+
+ memcpy (pad, src, sizeof(pad));
+ for (i = 0; i < rounds; i += 2)
+ {
+ SALSA20_CORE_DEBUG (i);
+ QROUND (pad[0], pad[4], pad[8], pad[12]);
+ QROUND (pad[5], pad[9], pad[13], pad[1] );
+ QROUND (pad[10], pad[14], pad[2], pad[6] );
+ QROUND (pad[15], pad[3], pad[7], pad[11]);
+
+ SALSA20_CORE_DEBUG (i+1);
+ QROUND (pad[0], pad[1], pad[2], pad[3] );
+ QROUND (pad[5], pad[6], pad[7], pad[4] );
+ QROUND (pad[10], pad[11], pad[8], pad[9] );
+ QROUND (pad[15], pad[12], pad[13], pad[14]);
+ }
+ SALSA20_CORE_DEBUG (i);
+
+ for (i = 0; i < SALSA20_INPUT_LENGTH; i++)
+ {
+ u32 t = pad[i] + src[i];
+ dst[i] = LE_SWAP32 (t);
+ }
+
+ /* Update counter. */
+ if (!++src[8])
+ src[9]++;
+
+ /* burn_stack */
+ return ( 3*sizeof (void*) \
+ + 2*sizeof (void*) \
+ + 64 \
+ + sizeof (unsigned int) \
+ + sizeof (u32) );
+}
+#undef QROUND
+#undef SALSA20_CORE_DEBUG
+
+static void
+salsa20_keysetup(SALSA20_context_t *ctx, const byte *key, int keylen)
+{
+ /* These constants are the little endian encoding of the string
+ "expand 32-byte k". For the 128 bit variant, the "32" in that
+ string will be fixed up to "16". */
+ ctx->input[0] = 0x61707865; /* "apxe" */
+ ctx->input[5] = 0x3320646e; /* "3 dn" */
+ ctx->input[10] = 0x79622d32; /* "yb-2" */
+ ctx->input[15] = 0x6b206574; /* "k et" */
+
+ ctx->input[1] = LE_READ_UINT32(key + 0);
+ ctx->input[2] = LE_READ_UINT32(key + 4);
+ ctx->input[3] = LE_READ_UINT32(key + 8);
+ ctx->input[4] = LE_READ_UINT32(key + 12);
+ if (keylen == SALSA20_MAX_KEY_SIZE) /* 256 bits */
+ {
+ ctx->input[11] = LE_READ_UINT32(key + 16);
+ ctx->input[12] = LE_READ_UINT32(key + 20);
+ ctx->input[13] = LE_READ_UINT32(key + 24);
+ ctx->input[14] = LE_READ_UINT32(key + 28);
+ }
+ else /* 128 bits */
+ {
+ ctx->input[11] = ctx->input[1];
+ ctx->input[12] = ctx->input[2];
+ ctx->input[13] = ctx->input[3];
+ ctx->input[14] = ctx->input[4];
+
+ ctx->input[5] -= 0x02000000; /* Change to "1 dn". */
+ ctx->input[10] += 0x00000004; /* Change to "yb-6". */
+ }
+}
+
+static void salsa20_ivsetup(SALSA20_context_t *ctx, const byte *iv)
+{
+ ctx->input[6] = LE_READ_UINT32(iv + 0);
+ ctx->input[7] = LE_READ_UINT32(iv + 4);
+ /* Reset the block counter. */
+ ctx->input[8] = 0;
+ ctx->input[9] = 0;
+}
+
+#endif /*!USE_AMD64*/
+
+#ifdef USE_ARM_NEON_ASM
+
+/* ARM NEON implementation of Salsa20. */
+unsigned int
+_gcry_arm_neon_salsa20_encrypt(void *c, const void *m, unsigned int nblks,
+ void *k, unsigned int rounds);
+
+static unsigned int
+salsa20_core_neon (u32 *dst, SALSA20_context_t *ctx, unsigned int rounds)
+{
+ return _gcry_arm_neon_salsa20_encrypt(dst, NULL, 1, ctx->input, rounds);
+}
+
+static void salsa20_ivsetup_neon(SALSA20_context_t *ctx, const byte *iv)
+{
+ memcpy(ctx->input + 8, iv, 8);
+ /* Reset the block counter. */
+ memset(ctx->input + 10, 0, 8);
+}
+
+static void
+salsa20_keysetup_neon(SALSA20_context_t *ctx, const byte *key, int klen)
+{
+ static const unsigned char sigma32[16] = "expand 32-byte k";
+ static const unsigned char sigma16[16] = "expand 16-byte k";
+
+ if (klen == 16)
+ {
+ memcpy (ctx->input, key, 16);
+ memcpy (ctx->input + 4, key, 16); /* Duplicate 128-bit key. */
+ memcpy (ctx->input + 12, sigma16, 16);
+ }
+ else
+ {
+ /* 32-byte key */
+ memcpy (ctx->input, key, 32);
+ memcpy (ctx->input + 12, sigma32, 16);
+ }
+}
+
+#endif /*USE_ARM_NEON_ASM*/
+
+
+static gcry_err_code_t
+salsa20_do_setkey (SALSA20_context_t *ctx,
+ const byte *key, unsigned int keylen)
+{
+ static int initialized;
+ static const char *selftest_failed;
+
+ if (!initialized )
+ {
+ initialized = 1;
+ selftest_failed = selftest ();
+ if (selftest_failed)
+ log_error ("SALSA20 selftest failed (%s)\n", selftest_failed );
+ }
+ if (selftest_failed)
+ return GPG_ERR_SELFTEST_FAILED;
+
+ if (keylen != SALSA20_MIN_KEY_SIZE
+ && keylen != SALSA20_MAX_KEY_SIZE)
+ return GPG_ERR_INV_KEYLEN;
+
+ /* Default ops. */
+ ctx->keysetup = salsa20_keysetup;
+ ctx->ivsetup = salsa20_ivsetup;
+ ctx->core = salsa20_core;
+
+#ifdef USE_ARM_NEON_ASM
+ ctx->use_neon = (_gcry_get_hw_features () & HWF_ARM_NEON) != 0;
+ if (ctx->use_neon)
+ {
+ /* Use ARM NEON ops instead. */
+ ctx->keysetup = salsa20_keysetup_neon;
+ ctx->ivsetup = salsa20_ivsetup_neon;
+ ctx->core = salsa20_core_neon;
+ }
+#endif
+
+ ctx->keysetup (ctx, key, keylen);
+
+ /* We default to a zero nonce. */
+ salsa20_setiv (ctx, NULL, 0);
+
+ return 0;
+}
+
+
+static gcry_err_code_t
+salsa20_setkey (void *context, const byte *key, unsigned int keylen,
+ cipher_bulk_ops_t *bulk_ops)
+{
+ SALSA20_context_t *ctx = (SALSA20_context_t *)context;
+ gcry_err_code_t rc = salsa20_do_setkey (ctx, key, keylen);
+ (void)bulk_ops;
+ _gcry_burn_stack (4 + sizeof (void *) + 4 * sizeof (void *));
+ return rc;
+}
+
+
+static void
+salsa20_setiv (void *context, const byte *iv, size_t ivlen)
+{
+ SALSA20_context_t *ctx = (SALSA20_context_t *)context;
+ byte tmp[SALSA20_IV_SIZE];
+
+ if (iv && ivlen != SALSA20_IV_SIZE)
+ log_info ("WARNING: salsa20_setiv: bad ivlen=%u\n", (u32)ivlen);
+
+ if (!iv || ivlen != SALSA20_IV_SIZE)
+ memset (tmp, 0, sizeof(tmp));
+ else
+ memcpy (tmp, iv, SALSA20_IV_SIZE);
+
+ ctx->ivsetup (ctx, tmp);
+
+ /* Reset the unused pad bytes counter. */
+ ctx->unused = 0;
+
+ wipememory (tmp, sizeof(tmp));
+}
+
+
+
+/* Note: This function requires LENGTH > 0. */
+static void
+salsa20_do_encrypt_stream (SALSA20_context_t *ctx,
+ byte *outbuf, const byte *inbuf,
+ size_t length, unsigned rounds)
+{
+ unsigned int nburn, burn = 0;
+
+ if (ctx->unused)
+ {
+ unsigned char *p = (void*)ctx->pad;
+ size_t n;
+
+ gcry_assert (ctx->unused < SALSA20_BLOCK_SIZE);
+
+ n = ctx->unused;
+ if (n > length)
+ n = length;
+ buf_xor (outbuf, inbuf, p + SALSA20_BLOCK_SIZE - ctx->unused, n);
+ length -= n;
+ outbuf += n;
+ inbuf += n;
+ ctx->unused -= n;
+ if (!length)
+ return;
+ gcry_assert (!ctx->unused);
+ }
+
+#ifdef USE_AMD64
+ if (length >= SALSA20_BLOCK_SIZE)
+ {
+ size_t nblocks = length / SALSA20_BLOCK_SIZE;
+ burn = _gcry_salsa20_amd64_encrypt_blocks(ctx->input, inbuf, outbuf,
+ nblocks, rounds);
+ burn += ASM_EXTRA_STACK;
+ length -= SALSA20_BLOCK_SIZE * nblocks;
+ outbuf += SALSA20_BLOCK_SIZE * nblocks;
+ inbuf += SALSA20_BLOCK_SIZE * nblocks;
+ }
+#endif
+
+#ifdef USE_ARM_NEON_ASM
+ if (ctx->use_neon && length >= SALSA20_BLOCK_SIZE)
+ {
+ unsigned int nblocks = length / SALSA20_BLOCK_SIZE;
+ _gcry_arm_neon_salsa20_encrypt (outbuf, inbuf, nblocks, ctx->input,
+ rounds);
+ length -= SALSA20_BLOCK_SIZE * nblocks;
+ outbuf += SALSA20_BLOCK_SIZE * nblocks;
+ inbuf += SALSA20_BLOCK_SIZE * nblocks;
+ }
+#endif
+
+ while (length > 0)
+ {
+ /* Create the next pad and bump the block counter. Note that it
+ is the user's duty to change to another nonce not later than
+ after 2^70 processed bytes. */
+ nburn = ctx->core (ctx->pad, ctx, rounds);
+ burn = nburn > burn ? nburn : burn;
+
+ if (length <= SALSA20_BLOCK_SIZE)
+ {
+ buf_xor (outbuf, inbuf, ctx->pad, length);
+ ctx->unused = SALSA20_BLOCK_SIZE - length;
+ break;
+ }
+ buf_xor (outbuf, inbuf, ctx->pad, SALSA20_BLOCK_SIZE);
+ length -= SALSA20_BLOCK_SIZE;
+ outbuf += SALSA20_BLOCK_SIZE;
+ inbuf += SALSA20_BLOCK_SIZE;
+ }
+
+ _gcry_burn_stack (burn);
+}
+
+
+static void
+salsa20_encrypt_stream (void *context,
+ byte *outbuf, const byte *inbuf, size_t length)
+{
+ SALSA20_context_t *ctx = (SALSA20_context_t *)context;
+
+ if (length)
+ salsa20_do_encrypt_stream (ctx, outbuf, inbuf, length, SALSA20_ROUNDS);
+}
+
+
+static void
+salsa20r12_encrypt_stream (void *context,
+ byte *outbuf, const byte *inbuf, size_t length)
+{
+ SALSA20_context_t *ctx = (SALSA20_context_t *)context;
+
+ if (length)
+ salsa20_do_encrypt_stream (ctx, outbuf, inbuf, length, SALSA20R12_ROUNDS);
+}
+
+
+static const char*
+selftest (void)
+{
+ byte ctxbuf[sizeof(SALSA20_context_t) + 15];
+ SALSA20_context_t *ctx;
+ byte scratch[8+1];
+ byte buf[256+64+4];
+ int i;
+
+ static byte key_1[] =
+ { 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+ static const byte nonce_1[] =
+ { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+ static const byte plaintext_1[] =
+ { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+ static const byte ciphertext_1[] =
+ { 0xE3, 0xBE, 0x8F, 0xDD, 0x8B, 0xEC, 0xA2, 0xE3};
+
+ /* 16-byte alignment required for amd64 implementation. */
+ ctx = (SALSA20_context_t *)((uintptr_t)(ctxbuf + 15) & ~(uintptr_t)15);
+
+ salsa20_setkey (ctx, key_1, sizeof key_1, NULL);
+ salsa20_setiv (ctx, nonce_1, sizeof nonce_1);
+ scratch[8] = 0;
+ salsa20_encrypt_stream (ctx, scratch, plaintext_1, sizeof plaintext_1);
+ if (memcmp (scratch, ciphertext_1, sizeof ciphertext_1))
+ return "Salsa20 encryption test 1 failed.";
+ if (scratch[8])
+ return "Salsa20 wrote too much.";
+ salsa20_setkey( ctx, key_1, sizeof(key_1), NULL);
+ salsa20_setiv (ctx, nonce_1, sizeof nonce_1);
+ salsa20_encrypt_stream (ctx, scratch, scratch, sizeof plaintext_1);
+ if (memcmp (scratch, plaintext_1, sizeof plaintext_1))
+ return "Salsa20 decryption test 1 failed.";
+
+ for (i = 0; i < sizeof buf; i++)
+ buf[i] = i;
+ salsa20_setkey (ctx, key_1, sizeof key_1, NULL);
+ salsa20_setiv (ctx, nonce_1, sizeof nonce_1);
+ /*encrypt*/
+ salsa20_encrypt_stream (ctx, buf, buf, sizeof buf);
+ /*decrypt*/
+ salsa20_setkey (ctx, key_1, sizeof key_1, NULL);
+ salsa20_setiv (ctx, nonce_1, sizeof nonce_1);
+ salsa20_encrypt_stream (ctx, buf, buf, 1);
+ salsa20_encrypt_stream (ctx, buf+1, buf+1, (sizeof buf)-1-1);
+ salsa20_encrypt_stream (ctx, buf+(sizeof buf)-1, buf+(sizeof buf)-1, 1);
+ for (i = 0; i < sizeof buf; i++)
+ if (buf[i] != (byte)i)
+ return "Salsa20 encryption test 2 failed.";
+
+ return NULL;
+}
+
+
+gcry_cipher_spec_t _gcry_cipher_spec_salsa20 =
+ {
+ GCRY_CIPHER_SALSA20,
+ {0, 0}, /* flags */
+ "SALSA20", /* name */
+ NULL, /* aliases */
+ NULL, /* oids */
+ 1, /* blocksize in bytes. */
+ SALSA20_MAX_KEY_SIZE*8, /* standard key length in bits. */
+ sizeof (SALSA20_context_t),
+ salsa20_setkey,
+ NULL,
+ NULL,
+ salsa20_encrypt_stream,
+ salsa20_encrypt_stream,
+ NULL,
+ NULL,
+ salsa20_setiv
+ };
+
+gcry_cipher_spec_t _gcry_cipher_spec_salsa20r12 =
+ {
+ GCRY_CIPHER_SALSA20R12,
+ {0, 0}, /* flags */
+ "SALSA20R12", /* name */
+ NULL, /* aliases */
+ NULL, /* oids */
+ 1, /* blocksize in bytes. */
+ SALSA20_MAX_KEY_SIZE*8, /* standard key length in bits. */
+ sizeof (SALSA20_context_t),
+ salsa20_setkey,
+ NULL,
+ NULL,
+ salsa20r12_encrypt_stream,
+ salsa20r12_encrypt_stream,
+ NULL,
+ NULL,
+ salsa20_setiv
+ };
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