smp web: implement protocol encodings and encryption end-to-end (#1778)

* smp web: protocol encodings and x3dh

* fix

* strnup761 compiled to wasm

* AES-256-GCM, comatibility tests

* core of double ratchet

* PQ double ratchet

* test typescript ratchets

* agent encoding/encryption stack with test

---------

Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>

Author: epoberezkin

smp-web/.gitignore

@@ -1,3 +1,4 @@
 node_modules/
 dist/
+dist-test/
 package-lock.json

smp-web/cbits/js_random.js

@@ -0,0 +1,14 @@
+addToLibrary({
+  js_random_bytes: function(buf, len) {
+    var bytes = new Uint8Array(len);
+    if (typeof crypto !== 'undefined' && crypto.getRandomValues) {
+      crypto.getRandomValues(bytes);
+    } else {
+      // Node.js fallback
+      var nodeCrypto = require('crypto');
+      var nodeBytes = nodeCrypto.randomBytes(len);
+      bytes.set(nodeBytes);
+    }
+    HEAPU8.set(bytes, buf);
+  }
+});

smp-web/cbits/sha512.c

@@ -0,0 +1,315 @@
+/*
+20080913
+D. J. Bernstein
+Public domain.
+
+SHA-512 implementation from SUPERCOP/NaCl.
+Source: https://bench.cr.yp.to/supercop.html
+  crypto_hashblocks/sha512/ref/blocks.c
+  crypto_hash/sha512/ref/hash.c
+
+Combined into a single file for WASM compilation alongside sntrup761.
+*/
+
+#include "sha512.h"
+
+typedef unsigned long long uint64;
+
+/* -- crypto_hashblocks_sha512 (blocks.c) -- */
+
+static uint64 load_bigendian(const unsigned char *x)
+{
+  return
+      (uint64) (x[7]) \
+  | (((uint64) (x[6])) << 8) \
+  | (((uint64) (x[5])) << 16) \
+  | (((uint64) (x[4])) << 24) \
+  | (((uint64) (x[3])) << 32) \
+  | (((uint64) (x[2])) << 40) \
+  | (((uint64) (x[1])) << 48) \
+  | (((uint64) (x[0])) << 56)
+  ;
+}
+
+static void store_bigendian(unsigned char *x,uint64 u)
+{
+  x[7] = u; u >>= 8;
+  x[6] = u; u >>= 8;
+  x[5] = u; u >>= 8;
+  x[4] = u; u >>= 8;
+  x[3] = u; u >>= 8;
+  x[2] = u; u >>= 8;
+  x[1] = u; u >>= 8;
+  x[0] = u;
+}
+
+#define SHR(x,c) ((x) >> (c))
+#define ROTR(x,c) (((x) >> (c)) | ((x) << (64 - (c))))
+
+#define Ch(x,y,z) ((x & y) ^ (~x & z))
+#define Maj(x,y,z) ((x & y) ^ (x & z) ^ (y & z))
+#define Sigma0(x) (ROTR(x,28) ^ ROTR(x,34) ^ ROTR(x,39))
+#define Sigma1(x) (ROTR(x,14) ^ ROTR(x,18) ^ ROTR(x,41))
+#define sigma0(x) (ROTR(x, 1) ^ ROTR(x, 8) ^ SHR(x,7))
+#define sigma1(x) (ROTR(x,19) ^ ROTR(x,61) ^ SHR(x,6))
+
+#define M(w0,w14,w9,w1) w0 = sigma1(w14) + w9 + sigma0(w1) + w0;
+
+#define EXPAND \
+  M(w0 ,w14,w9 ,w1 ) \
+  M(w1 ,w15,w10,w2 ) \
+  M(w2 ,w0 ,w11,w3 ) \
+  M(w3 ,w1 ,w12,w4 ) \
+  M(w4 ,w2 ,w13,w5 ) \
+  M(w5 ,w3 ,w14,w6 ) \
+  M(w6 ,w4 ,w15,w7 ) \
+  M(w7 ,w5 ,w0 ,w8 ) \
+  M(w8 ,w6 ,w1 ,w9 ) \
+  M(w9 ,w7 ,w2 ,w10) \
+  M(w10,w8 ,w3 ,w11) \
+  M(w11,w9 ,w4 ,w12) \
+  M(w12,w10,w5 ,w13) \
+  M(w13,w11,w6 ,w14) \
+  M(w14,w12,w7 ,w15) \
+  M(w15,w13,w8 ,w0 )
+
+#define F(w,k) \
+  T1 = h + Sigma1(e) + Ch(e,f,g) + k + w; \
+  T2 = Sigma0(a) + Maj(a,b,c); \
+  h = g; \
+  g = f; \
+  f = e; \
+  e = d + T1; \
+  d = c; \
+  c = b; \
+  b = a; \
+  a = T1 + T2;
+
+static int crypto_hashblocks_sha512(unsigned char *statebytes,const unsigned char *in,unsigned long long inlen)
+{
+  uint64 state[8];
+  uint64 a;
+  uint64 b;
+  uint64 c;
+  uint64 d;
+  uint64 e;
+  uint64 f;
+  uint64 g;
+  uint64 h;
+  uint64 T1;
+  uint64 T2;
+
+  a = load_bigendian(statebytes +  0); state[0] = a;
+  b = load_bigendian(statebytes +  8); state[1] = b;
+  c = load_bigendian(statebytes + 16); state[2] = c;
+  d = load_bigendian(statebytes + 24); state[3] = d;
+  e = load_bigendian(statebytes + 32); state[4] = e;
+  f = load_bigendian(statebytes + 40); state[5] = f;
+  g = load_bigendian(statebytes + 48); state[6] = g;
+  h = load_bigendian(statebytes + 56); state[7] = h;
+
+  while (inlen >= 128) {
+    uint64 w0  = load_bigendian(in +   0);
+    uint64 w1  = load_bigendian(in +   8);
+    uint64 w2  = load_bigendian(in +  16);
+    uint64 w3  = load_bigendian(in +  24);
+    uint64 w4  = load_bigendian(in +  32);
+    uint64 w5  = load_bigendian(in +  40);
+    uint64 w6  = load_bigendian(in +  48);
+    uint64 w7  = load_bigendian(in +  56);
+    uint64 w8  = load_bigendian(in +  64);
+    uint64 w9  = load_bigendian(in +  72);
+    uint64 w10 = load_bigendian(in +  80);
+    uint64 w11 = load_bigendian(in +  88);
+    uint64 w12 = load_bigendian(in +  96);
+    uint64 w13 = load_bigendian(in + 104);
+    uint64 w14 = load_bigendian(in + 112);
+    uint64 w15 = load_bigendian(in + 120);
+
+    F(w0 ,0x428a2f98d728ae22ULL)
+    F(w1 ,0x7137449123ef65cdULL)
+    F(w2 ,0xb5c0fbcfec4d3b2fULL)
+    F(w3 ,0xe9b5dba58189dbbcULL)
+    F(w4 ,0x3956c25bf348b538ULL)
+    F(w5 ,0x59f111f1b605d019ULL)
+    F(w6 ,0x923f82a4af194f9bULL)
+    F(w7 ,0xab1c5ed5da6d8118ULL)
+    F(w8 ,0xd807aa98a3030242ULL)
+    F(w9 ,0x12835b0145706fbeULL)
+    F(w10,0x243185be4ee4b28cULL)
+    F(w11,0x550c7dc3d5ffb4e2ULL)
+    F(w12,0x72be5d74f27b896fULL)
+    F(w13,0x80deb1fe3b1696b1ULL)
+    F(w14,0x9bdc06a725c71235ULL)
+    F(w15,0xc19bf174cf692694ULL)
+
+    EXPAND
+
+    F(w0 ,0xe49b69c19ef14ad2ULL)
+    F(w1 ,0xefbe4786384f25e3ULL)
+    F(w2 ,0x0fc19dc68b8cd5b5ULL)
+    F(w3 ,0x240ca1cc77ac9c65ULL)
+    F(w4 ,0x2de92c6f592b0275ULL)
+    F(w5 ,0x4a7484aa6ea6e483ULL)
+    F(w6 ,0x5cb0a9dcbd41fbd4ULL)
+    F(w7 ,0x76f988da831153b5ULL)
+    F(w8 ,0x983e5152ee66dfabULL)
+    F(w9 ,0xa831c66d2db43210ULL)
+    F(w10,0xb00327c898fb213fULL)
+    F(w11,0xbf597fc7beef0ee4ULL)
+    F(w12,0xc6e00bf33da88fc2ULL)
+    F(w13,0xd5a79147930aa725ULL)
+    F(w14,0x06ca6351e003826fULL)
+    F(w15,0x142929670a0e6e70ULL)
+
+    EXPAND
+
+    F(w0 ,0x27b70a8546d22ffcULL)
+    F(w1 ,0x2e1b21385c26c926ULL)
+    F(w2 ,0x4d2c6dfc5ac42aedULL)
+    F(w3 ,0x53380d139d95b3dfULL)
+    F(w4 ,0x650a73548baf63deULL)
+    F(w5 ,0x766a0abb3c77b2a8ULL)
+    F(w6 ,0x81c2c92e47edaee6ULL)
+    F(w7 ,0x92722c851482353bULL)
+    F(w8 ,0xa2bfe8a14cf10364ULL)
+    F(w9 ,0xa81a664bbc423001ULL)
+    F(w10,0xc24b8b70d0f89791ULL)
+    F(w11,0xc76c51a30654be30ULL)
+    F(w12,0xd192e819d6ef5218ULL)
+    F(w13,0xd69906245565a910ULL)
+    F(w14,0xf40e35855771202aULL)
+    F(w15,0x106aa07032bbd1b8ULL)
+
+    EXPAND
+
+    F(w0 ,0x19a4c116b8d2d0c8ULL)
+    F(w1 ,0x1e376c085141ab53ULL)
+    F(w2 ,0x2748774cdf8eeb99ULL)
+    F(w3 ,0x34b0bcb5e19b48a8ULL)
+    F(w4 ,0x391c0cb3c5c95a63ULL)
+    F(w5 ,0x4ed8aa4ae3418acbULL)
+    F(w6 ,0x5b9cca4f7763e373ULL)
+    F(w7 ,0x682e6ff3d6b2b8a3ULL)
+    F(w8 ,0x748f82ee5defb2fcULL)
+    F(w9 ,0x78a5636f43172f60ULL)
+    F(w10,0x84c87814a1f0ab72ULL)
+    F(w11,0x8cc702081a6439ecULL)
+    F(w12,0x90befffa23631e28ULL)
+    F(w13,0xa4506cebde82bde9ULL)
+    F(w14,0xbef9a3f7b2c67915ULL)
+    F(w15,0xc67178f2e372532bULL)
+
+    EXPAND
+
+    F(w0 ,0xca273eceea26619cULL)
+    F(w1 ,0xd186b8c721c0c207ULL)
+    F(w2 ,0xeada7dd6cde0eb1eULL)
+    F(w3 ,0xf57d4f7fee6ed178ULL)
+    F(w4 ,0x06f067aa72176fbaULL)
+    F(w5 ,0x0a637dc5a2c898a6ULL)
+    F(w6 ,0x113f9804bef90daeULL)
+    F(w7 ,0x1b710b35131c471bULL)
+    F(w8 ,0x28db77f523047d84ULL)
+    F(w9 ,0x32caab7b40c72493ULL)
+    F(w10,0x3c9ebe0a15c9bebcULL)
+    F(w11,0x431d67c49c100d4cULL)
+    F(w12,0x4cc5d4becb3e42b6ULL)
+    F(w13,0x597f299cfc657e2aULL)
+    F(w14,0x5fcb6fab3ad6faecULL)
+    F(w15,0x6c44198c4a475817ULL)
+
+    a += state[0];
+    b += state[1];
+    c += state[2];
+    d += state[3];
+    e += state[4];
+    f += state[5];
+    g += state[6];
+    h += state[7];
+
+    state[0] = a;
+    state[1] = b;
+    state[2] = c;
+    state[3] = d;
+    state[4] = e;
+    state[5] = f;
+    state[6] = g;
+    state[7] = h;
+
+    in += 128;
+    inlen -= 128;
+  }
+
+  store_bigendian(statebytes +  0,state[0]);
+  store_bigendian(statebytes +  8,state[1]);
+  store_bigendian(statebytes + 16,state[2]);
+  store_bigendian(statebytes + 24,state[3]);
+  store_bigendian(statebytes + 32,state[4]);
+  store_bigendian(statebytes + 40,state[5]);
+  store_bigendian(statebytes + 48,state[6]);
+  store_bigendian(statebytes + 56,state[7]);
+
+  return inlen;
+}
+
+/* -- crypto_hash_sha512 (hash.c) -- */
+
+static const unsigned char iv[64] = {
+  0x6a,0x09,0xe6,0x67,0xf3,0xbc,0xc9,0x08,
+  0xbb,0x67,0xae,0x85,0x84,0xca,0xa7,0x3b,
+  0x3c,0x6e,0xf3,0x72,0xfe,0x94,0xf8,0x2b,
+  0xa5,0x4f,0xf5,0x3a,0x5f,0x1d,0x36,0xf1,
+  0x51,0x0e,0x52,0x7f,0xad,0xe6,0x82,0xd1,
+  0x9b,0x05,0x68,0x8c,0x2b,0x3e,0x6c,0x1f,
+  0x1f,0x83,0xd9,0xab,0xfb,0x41,0xbd,0x6b,
+  0x5b,0xe0,0xcd,0x19,0x13,0x7e,0x21,0x79
+};
+
+void crypto_hash_sha512(unsigned char *out,
+                        const unsigned char *in,
+                        unsigned long long inlen)
+{
+  unsigned char h[64];
+  unsigned char padded[256];
+  int i;
+  unsigned long long bytes = inlen;
+
+  for (i = 0;i < 64;++i) h[i] = iv[i];
+
+  crypto_hashblocks_sha512(h,in,inlen);
+  in += inlen;
+  inlen &= 127;
+  in -= inlen;
+
+  for (i = 0;i < (int)inlen;++i) padded[i] = in[i];
+  padded[inlen] = 0x80;
+
+  if (inlen < 112) {
+    for (i = inlen + 1;i < 119;++i) padded[i] = 0;
+    padded[119] = bytes >> 61;
+    padded[120] = bytes >> 53;
+    padded[121] = bytes >> 45;
+    padded[122] = bytes >> 37;
+    padded[123] = bytes >> 29;
+    padded[124] = bytes >> 21;
+    padded[125] = bytes >> 13;
+    padded[126] = bytes >> 5;
+    padded[127] = bytes << 3;
+    crypto_hashblocks_sha512(h,padded,128);
+  } else {
+    for (i = inlen + 1;i < 247;++i) padded[i] = 0;
+    padded[247] = bytes >> 61;
+    padded[248] = bytes >> 53;
+    padded[249] = bytes >> 45;
+    padded[250] = bytes >> 37;
+    padded[251] = bytes >> 29;
+    padded[252] = bytes >> 21;
+    padded[253] = bytes >> 13;
+    padded[254] = bytes >> 5;
+    padded[255] = bytes << 3;
+    crypto_hashblocks_sha512(h,padded,256);
+  }
+
+  for (i = 0;i < 64;++i) out[i] = h[i];
+}

smp-web/cbits/sntrup761.d.mts

@@ -0,0 +1,11 @@
+interface Sntrup761Module {
+  _sntrup761_wasm_keypair(pk: number, sk: number): void
+  _sntrup761_wasm_enc(c: number, k: number, pk: number): void
+  _sntrup761_wasm_dec(k: number, c: number, sk: number): void
+  _malloc(size: number): number
+  _free(ptr: number): void
+  HEAPU8: Uint8Array
+}
+
+declare function createSntrup761(): Promise<Sntrup761Module>
+export default createSntrup761

smp-web/cbits/sntrup761_wasm.c

@@ -0,0 +1,34 @@
+/*
+ * WASM wrapper for sntrup761.
+ * Provides JS-callable functions with RNG from JS imports.
+ *
+ * Build: emcc sntrup761_wasm.c sntrup761.c sha512.c -O2 -o sntrup761.js \
+ *        -s EXPORTED_FUNCTIONS='["_sntrup761_wasm_keypair","_sntrup761_wasm_enc","_sntrup761_wasm_dec","_malloc","_free"]' \
+ *        -s EXPORTED_RUNTIME_METHODS='["ccall","cwrap"]'
+ */
+
+#include "sntrup761.h"
+#include <stdlib.h>
+
+/* Import RNG from JS environment */
+extern void js_random_bytes(unsigned char *buf, int len);
+
+/* RNG callback adapter for sntrup761 */
+static void wasm_random(void *ctx, size_t length, uint8_t *dst) {
+  (void)ctx;
+  js_random_bytes(dst, (int)length);
+}
+
+/* JS-callable wrappers */
+
+void sntrup761_wasm_keypair(unsigned char *pk, unsigned char *sk) {
+  sntrup761_keypair(pk, sk, NULL, wasm_random);
+}
+
+void sntrup761_wasm_enc(unsigned char *c, unsigned char *k, const unsigned char *pk) {
+  sntrup761_enc(c, k, pk, NULL, wasm_random);
+}
+
+void sntrup761_wasm_dec(unsigned char *k, const unsigned char *c, const unsigned char *sk) {
+  sntrup761_dec(k, c, sk);
+}