Import tiny_sha3

This is a minimal and readable SHA3 implementation.

ok tb@

2 files changed, 238 insertions, 0 deletions

diff --git a/src/lib/libcrypto/sha/sha3.c b/src/lib/libcrypto/sha/sha3.c
new file mode 100644
index 0000000000..931ae02084
--- /dev/null
+++ b/src/lib/libcrypto/sha/sha3.c
@@ -0,0 +1,191 @@
+// sha3.c
+// 19-Nov-11  Markku-Juhani O. Saarinen <mjos@iki.fi>
+
+// Revised 07-Aug-15 to match with official release of FIPS PUB 202 "SHA3"
+// Revised 03-Sep-15 for portability + OpenSSL - style API
+
+#include "sha3.h"
+
+// update the state with given number of rounds
+
+void sha3_keccakf(uint64_t st[25])
+{
+    // constants
+    const uint64_t keccakf_rndc[24] = {
+        0x0000000000000001, 0x0000000000008082, 0x800000000000808a,
+        0x8000000080008000, 0x000000000000808b, 0x0000000080000001,
+        0x8000000080008081, 0x8000000000008009, 0x000000000000008a,
+        0x0000000000000088, 0x0000000080008009, 0x000000008000000a,
+        0x000000008000808b, 0x800000000000008b, 0x8000000000008089,
+        0x8000000000008003, 0x8000000000008002, 0x8000000000000080,
+        0x000000000000800a, 0x800000008000000a, 0x8000000080008081,
+        0x8000000000008080, 0x0000000080000001, 0x8000000080008008
+    };
+    const int keccakf_rotc[24] = {
+        1,  3,  6,  10, 15, 21, 28, 36, 45, 55, 2,  14,
+        27, 41, 56, 8,  25, 43, 62, 18, 39, 61, 20, 44
+    };
+    const int keccakf_piln[24] = {
+        10, 7,  11, 17, 18, 3, 5,  16, 8,  21, 24, 4,
+        15, 23, 19, 13, 12, 2, 20, 14, 22, 9,  6,  1
+    };
+
+    // variables
+    int i, j, r;
+    uint64_t t, bc[5];
+
+#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
+    uint8_t *v;
+
+    // endianess conversion. this is redundant on little-endian targets
+    for (i = 0; i < 25; i++) {
+        v = (uint8_t *) &st[i];
+        st[i] = ((uint64_t) v[0])     | (((uint64_t) v[1]) << 8) |
+            (((uint64_t) v[2]) << 16) | (((uint64_t) v[3]) << 24) |
+            (((uint64_t) v[4]) << 32) | (((uint64_t) v[5]) << 40) |
+            (((uint64_t) v[6]) << 48) | (((uint64_t) v[7]) << 56);
+    }
+#endif
+
+    // actual iteration
+    for (r = 0; r < KECCAKF_ROUNDS; r++) {
+
+        // Theta
+        for (i = 0; i < 5; i++)
+            bc[i] = st[i] ^ st[i + 5] ^ st[i + 10] ^ st[i + 15] ^ st[i + 20];
+
+        for (i = 0; i < 5; i++) {
+            t = bc[(i + 4) % 5] ^ ROTL64(bc[(i + 1) % 5], 1);
+            for (j = 0; j < 25; j += 5)
+                st[j + i] ^= t;
+        }
+
+        // Rho Pi
+        t = st[1];
+        for (i = 0; i < 24; i++) {
+            j = keccakf_piln[i];
+            bc[0] = st[j];
+            st[j] = ROTL64(t, keccakf_rotc[i]);
+            t = bc[0];
+        }
+
+        //  Chi
+        for (j = 0; j < 25; j += 5) {
+            for (i = 0; i < 5; i++)
+                bc[i] = st[j + i];
+            for (i = 0; i < 5; i++)
+                st[j + i] ^= (~bc[(i + 1) % 5]) & bc[(i + 2) % 5];
+        }
+
+        //  Iota
+        st[0] ^= keccakf_rndc[r];
+    }
+
+#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
+    // endianess conversion. this is redundant on little-endian targets
+    for (i = 0; i < 25; i++) {
+        v = (uint8_t *) &st[i];
+        t = st[i];
+        v[0] = t & 0xFF;
+        v[1] = (t >> 8) & 0xFF;
+        v[2] = (t >> 16) & 0xFF;
+        v[3] = (t >> 24) & 0xFF;
+        v[4] = (t >> 32) & 0xFF;
+        v[5] = (t >> 40) & 0xFF;
+        v[6] = (t >> 48) & 0xFF;
+        v[7] = (t >> 56) & 0xFF;
+    }
+#endif
+}
+
+// Initialize the context for SHA3
+
+int sha3_init(sha3_ctx_t *c, int mdlen)
+{
+    int i;
+
+    for (i = 0; i < 25; i++)
+        c->st.q[i] = 0;
+    c->mdlen = mdlen;
+    c->rsiz = 200 - 2 * mdlen;
+    c->pt = 0;
+
+    return 1;
+}
+
+// update state with more data
+
+int sha3_update(sha3_ctx_t *c, const void *data, size_t len)
+{
+    size_t i;
+    int j;
+
+    j = c->pt;
+    for (i = 0; i < len; i++) {
+        c->st.b[j++] ^= ((const uint8_t *) data)[i];
+        if (j >= c->rsiz) {
+            sha3_keccakf(c->st.q);
+            j = 0;
+        }
+    }
+    c->pt = j;
+
+    return 1;
+}
+
+// finalize and output a hash
+
+int sha3_final(void *md, sha3_ctx_t *c)
+{
+    int i;
+
+    c->st.b[c->pt] ^= 0x06;
+    c->st.b[c->rsiz - 1] ^= 0x80;
+    sha3_keccakf(c->st.q);
+
+    for (i = 0; i < c->mdlen; i++) {
+        ((uint8_t *) md)[i] = c->st.b[i];
+    }
+
+    return 1;
+}
+
+// compute a SHA-3 hash (md) of given byte length from "in"
+
+void *sha3(const void *in, size_t inlen, void *md, int mdlen)
+{
+    sha3_ctx_t sha3;
+
+    sha3_init(&sha3, mdlen);
+    sha3_update(&sha3, in, inlen);
+    sha3_final(md, &sha3);
+
+    return md;
+}
+
+// SHAKE128 and SHAKE256 extensible-output functionality
+
+void shake_xof(sha3_ctx_t *c)
+{
+    c->st.b[c->pt] ^= 0x1F;
+    c->st.b[c->rsiz - 1] ^= 0x80;
+    sha3_keccakf(c->st.q);
+    c->pt = 0;
+}
+
+void shake_out(sha3_ctx_t *c, void *out, size_t len)
+{
+    size_t i;
+    int j;
+
+    j = c->pt;
+    for (i = 0; i < len; i++) {
+        if (j >= c->rsiz) {
+            sha3_keccakf(c->st.q);
+            j = 0;
+        }
+        ((uint8_t *) out)[i] = c->st.b[j++];
+    }
+    c->pt = j;
+}
+
diff --git a/src/lib/libcrypto/sha/sha3_internal.h b/src/lib/libcrypto/sha/sha3_internal.h
new file mode 100644
index 0000000000..ba24f43478
--- /dev/null
+++ b/src/lib/libcrypto/sha/sha3_internal.h
@@ -0,0 +1,47 @@
+// sha3.h
+// 19-Nov-11  Markku-Juhani O. Saarinen <mjos@iki.fi>
+
+#ifndef SHA3_H
+#define SHA3_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifndef KECCAKF_ROUNDS
+#define KECCAKF_ROUNDS 24
+#endif
+
+#ifndef ROTL64
+#define ROTL64(x, y) (((x) << (y)) | ((x) >> (64 - (y))))
+#endif
+
+// state context
+typedef struct {
+    union {                                 // state:
+        uint8_t b[200];                     // 8-bit bytes
+        uint64_t q[25];                     // 64-bit words
+    } st;
+    int pt, rsiz, mdlen;                    // these don't overflow
+} sha3_ctx_t;
+
+// Compression function.
+void sha3_keccakf(uint64_t st[25]);
+
+// OpenSSL - like interfece
+int sha3_init(sha3_ctx_t *c, int mdlen);    // mdlen = hash output in bytes
+int sha3_update(sha3_ctx_t *c, const void *data, size_t len);
+int sha3_final(void *md, sha3_ctx_t *c);    // digest goes to md
+
+// compute a sha3 hash (md) of given byte length from "in"
+void *sha3(const void *in, size_t inlen, void *md, int mdlen);
+
+// SHAKE128 and SHAKE256 extensible-output functions
+#define shake128_init(c) sha3_init(c, 16)
+#define shake256_init(c) sha3_init(c, 32)
+#define shake_update sha3_update
+
+void shake_xof(sha3_ctx_t *c);
+void shake_out(sha3_ctx_t *c, void *out, size_t len);
+
+#endif
+