preprocessing.cpp 17 KB

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  1. #include <type_traits> // std::is_same<>
  2. #include <limits> // std::numeric_limits<>
  3. #include <climits> // CHAR_BIT
  4. #include <cmath> // std::log2, std::ceil, std::floor
  5. #include <stdexcept> // std::runtime_error
  6. #include <array> // std::array<>
  7. #include <iostream> // std::istream and std::ostream
  8. #include <vector> // std::vector<>
  9. #include <memory> // std::shared_ptr<>
  10. #include <utility> // std::move
  11. #include <algorithm> // std::copy
  12. #include <cstring> // std::memcpy
  13. #include <bsd/stdlib.h> // arc4random_buf
  14. #include <x86intrin.h> // SSE and AVX intrinsics
  15. #include <boost/asio/thread_pool.hpp>
  16. size_t communication_cost = 0;
  17. #include "bitutils.h"
  18. #include "block.h"
  19. #include "prg.h"
  20. #include "prg_aes_impl.h"
  21. #include <iostream>
  22. #include <fcntl.h>
  23. #include <cstdlib>
  24. #include "block.h"
  25. #include <chrono>
  26. #include <sys/mman.h>
  27. #include <sys/stat.h>
  28. #include <fcntl.h>
  29. #include <fstream>
  30. #include <future>
  31. #include <boost/asio.hpp>
  32. using boost::asio::ip::tcp;
  33. #include <mutex>
  34. #include <boost/lexical_cast.hpp>
  35. using socket_t = boost::asio::ip::tcp::socket;
  36. typedef unsigned char byte_t;
  37. typedef __m128i node_t;
  38. block<__m128i> seed_for_blinds;
  39. constexpr size_t leaf_size = 1;
  40. typedef __m128i leaf_type;
  41. typedef std::array<leaf_type, leaf_size> leaf_t;
  42. size_t bits_per_leaf = std::is_same<leaf_t, bool>::value ? 1 : sizeof(leaf_t) * CHAR_BIT;
  43. bool is_packed = (sizeof(leaf_t) < sizeof(node_t));
  44. size_t leaves_per_node = is_packed ? sizeof(node_t) * CHAR_BIT / bits_per_leaf : 1;
  45. size_t input_bits(const size_t nitems) { return std::ceil(std::log2(nitems)); }
  46. leaf_t val;
  47. using namespace dpf;
  48. #include "mpc.h"
  49. void generate_random_targets(uint8_t **target_share_read, size_t n_threads, bool party, size_t expo)
  50. {
  51. for (size_t i = 0; i < n_threads; i++)
  52. {
  53. target_share_read[i] = new uint8_t[64];
  54. }
  55. for (size_t j = 0; j < 64; ++j)
  56. {
  57. for (size_t i = 0; i < n_threads; ++i)
  58. {
  59. uint8_t random_value;
  60. arc4random_buf(&random_value, sizeof(uint8_t));
  61. target_share_read[i][j] = random_value; // rand();
  62. }
  63. }
  64. }
  65. void compute_CW(bool party, tcp::socket &sout, __m128i L, __m128i R, uint8_t bit, __m128i &CW)
  66. {
  67. // struct cw_construction
  68. //{
  69. __m128i rand_b, gamma_b;
  70. uint8_t bit_b;
  71. //};
  72. __m128i *X, *Y;
  73. if (party)
  74. {
  75. std::string qfile = std::string("./gamma1");
  76. int qfd = open(qfile.c_str(), O_RDWR);
  77. X = (__m128i *)mmap(NULL, 8 * sizeof(__m128i),
  78. PROT_READ, MAP_PRIVATE, qfd, 0);
  79. qfile = std::string("./x1");
  80. qfd = open(qfile.c_str(), O_RDWR);
  81. Y = (__m128i *)mmap(NULL, 8 * sizeof(__m128i),
  82. PROT_READ, MAP_PRIVATE, qfd, 0);
  83. }
  84. if (!party)
  85. {
  86. std::string qfile = std::string("./gamma0");
  87. int qfd = open(qfile.c_str(), O_RDWR);
  88. X = (__m128i *)mmap(NULL, 8 * sizeof(__m128i),
  89. PROT_READ, MAP_PRIVATE, qfd, 0);
  90. qfile = std::string("./x0");
  91. qfd = open(qfile.c_str(), O_RDWR);
  92. Y = (__m128i *)mmap(NULL, 8 * sizeof(__m128i),
  93. PROT_READ, MAP_PRIVATE, qfd, 0);
  94. }
  95. // cw_construction computecw;
  96. // read(sin, boost::asio::buffer(&computecw, sizeof(computecw)));
  97. // computecw.rand_b;
  98. //__m128i gamma_b = computecw.gamma_b;
  99. if (party)
  100. {
  101. rand_b = Y[0]; //_mm_set_epi32(0x6fef9434, 0x6768121e, 0x20942286, 0x1b59f7a7);
  102. gamma_b = X[0]; // _mm_set_epi32(0x6a499109 , 0x803067dd , 0xd1e2281b , 0xe71b6262);
  103. bit_b = 1; // computecw.bit_b;
  104. }
  105. else
  106. {
  107. rand_b = Y[0]; // _mm_set_epi32(0xb29747df, 0xf7300f6d, 0x9476d971, 0xd5f75d98);
  108. gamma_b = X[0]; // _mm_set_epi32(0xb73142e2 , 0x10687aae , 0x06500d3ec , 0x29b5c85d);
  109. bit_b = 1; // computecw.bit_b;
  110. }
  111. uint8_t blinded_bit, blinded_bit_read;
  112. blinded_bit = bit ^ bit_b;
  113. __m128i blinded_L = L ^ R ^ rand_b;
  114. __m128i blinded_L_read;
  115. struct BlindsCW
  116. {
  117. __m128i blinded_message;
  118. uint8_t blinded_bit;
  119. };
  120. BlindsCW blinds_sent, blinds_recv;
  121. blinds_sent.blinded_bit = blinded_bit;
  122. blinds_sent.blinded_message = blinded_L;
  123. boost::asio::write(sout, boost::asio::buffer(&blinds_sent, sizeof(blinds_sent)));
  124. boost::asio::read(sout, boost::asio::buffer(&blinds_recv, sizeof(blinds_recv)));
  125. communication_cost += sizeof(blinds_recv);
  126. blinded_bit_read = blinds_recv.blinded_bit;
  127. blinded_L_read = blinds_recv.blinded_message;
  128. __m128i out_ = R ^ gamma_b; //_mm_setzero_si128;
  129. if (bit)
  130. {
  131. out_ ^= (L ^ R ^ blinded_L_read);
  132. }
  133. if (blinded_bit_read)
  134. {
  135. out_ ^= rand_b;
  136. }
  137. __m128i out_reconstruction;
  138. boost::asio::write(sout, boost::asio::buffer(&out_, sizeof(out_)));
  139. boost::asio::read(sout, boost::asio::buffer(&out_reconstruction, sizeof(out_reconstruction)));
  140. communication_cost += sizeof(out_reconstruction);
  141. out_reconstruction = out_ ^ out_reconstruction;
  142. CW = out_reconstruction;
  143. #ifdef DEBUG
  144. uint8_t bit_reconstruction;
  145. boost::asio::write(sout, boost::asio::buffer(&bit, sizeof(bit)));
  146. boost::asio::read(sout, boost::asio::buffer(&bit_reconstruction, sizeof(bit_reconstruction)));
  147. bit_reconstruction = bit ^ bit_reconstruction;
  148. __m128i L_reconstruction;
  149. boost::asio::write(sout, boost::asio::buffer(&L, sizeof(L)));
  150. boost::asio::read(sout, boost::asio::buffer(&L_reconstruction, sizeof(L_reconstruction)));
  151. L_reconstruction = L ^ L_reconstruction;
  152. __m128i R_reconstruction;
  153. boost::asio::write(sout, boost::asio::buffer(&R, sizeof(R)));
  154. boost::asio::read(sout, boost::asio::buffer(&R_reconstruction, sizeof(R_reconstruction)));
  155. R_reconstruction = R ^ R_reconstruction;
  156. __m128i CW_debug;
  157. if (bit_reconstruction != 0)
  158. {
  159. CW_debug = L_reconstruction;
  160. }
  161. else
  162. {
  163. CW_debug = R_reconstruction;
  164. }
  165. assert(CW_debug[0] == CW[0]);
  166. assert(CW_debug[1] == CW[1]);
  167. #endif
  168. }
  169. __m128i bit_mask_avx2_msb(unsigned int n)
  170. {
  171. __m128i ones = _mm_set1_epi32(-1);
  172. __m128i cnst32_128 = _mm_set_epi32(32, 64, 96, 128);
  173. __m128i shift = _mm_set1_epi32(n);
  174. shift = _mm_subs_epu16(cnst32_128, shift);
  175. return _mm_sllv_epi32(ones, shift);
  176. }
  177. __m128i bit_mask_avx2_lsb(unsigned int n)
  178. {
  179. __m128i ones = _mm_set1_epi32(-1);
  180. __m128i cnst32_128 = _mm_set_epi32(128, 96, 64, 32);
  181. __m128i shift = _mm_set1_epi32(n);
  182. shift = _mm_subs_epu16(cnst32_128, shift);
  183. return _mm_srlv_epi32(ones, shift);
  184. }
  185. template <typename node_t, typename prgkey_t>
  186. static inline void traverse(const prgkey_t &prgkey, const node_t &seed, node_t s[2])
  187. {
  188. dpf::PRG(prgkey, clear_lsb(seed, 0b11), s, 2);
  189. } // dpf::expand
  190. inline void evalfull_mpc(const size_t &nodes_per_leaf, const size_t &depth, const size_t &nbits, const size_t &nodes_in_interval,
  191. const AES_KEY &prgkey, uint8_t target_share[64], std::vector<socket_t> &socketsPb,
  192. const size_t from, const size_t to, __m128i *output, int8_t *_t, __m128i &final_correction_word, bool party, size_t socket_no = 0)
  193. {
  194. __m128i root;
  195. arc4random_buf(&root, sizeof(root));
  196. root = set_lsb(root, party);
  197. const size_t from_node = std::floor(static_cast<double>(from) / nodes_per_leaf);
  198. __m128i *s[2] = {
  199. reinterpret_cast<__m128i *>(output) + nodes_in_interval * (nodes_per_leaf - 1),
  200. s[0] + nodes_in_interval / 2};
  201. int8_t *t[2] = {_t, _t + nodes_in_interval / 2};
  202. int curlayer = depth % 2;
  203. s[curlayer][0] = root;
  204. t[curlayer][0] = get_lsb(root, 0b01);
  205. __m128i *CW = (__m128i *)std::aligned_alloc(sizeof(__m256i), depth * sizeof(__m128i));
  206. for (size_t layer = 0; layer < depth; ++layer)
  207. {
  208. #ifdef VERBOSE
  209. printf("layer = %zu\n", layer);
  210. #endif
  211. curlayer = 1 - curlayer;
  212. size_t i = 0, j = 0;
  213. auto nextbit = (from_node >> (nbits - layer - 1)) & 1;
  214. size_t nodes_in_prev_layer = std::ceil(static_cast<double>(nodes_in_interval) / (1ULL << (depth - layer)));
  215. size_t nodes_in_cur_layer = std::ceil(static_cast<double>(nodes_in_interval) / (1ULL << (depth - layer - 1)));
  216. __m128i L = _mm_setzero_si128();
  217. __m128i R = _mm_setzero_si128();
  218. for (i = nextbit, j = nextbit; j < nodes_in_prev_layer - 1; ++j, i += 2)
  219. {
  220. traverse(prgkey, s[1 - curlayer][j], &s[curlayer][i]);
  221. L ^= s[curlayer][i];
  222. R ^= s[curlayer][i + 1];
  223. }
  224. if (nodes_in_prev_layer > j)
  225. {
  226. if (i < nodes_in_cur_layer - 1)
  227. {
  228. traverse(prgkey, s[1 - curlayer][j], &s[curlayer][i]);
  229. L ^= s[curlayer][i];
  230. R ^= s[curlayer][i + 1];
  231. }
  232. }
  233. compute_CW(party, socketsPb[socket_no], L, R, target_share[layer], CW[layer]);
  234. uint8_t advice_L = get_lsb(L) ^ target_share[layer];
  235. uint8_t advice_R = get_lsb(R) ^ target_share[layer];
  236. uint8_t cwt_L, cwt_R;
  237. uint8_t advice[2];
  238. uint8_t cwts[2];
  239. advice[0] = advice_L;
  240. advice[1] = advice_R;
  241. boost::asio::write(socketsPb[socket_no + 1], boost::asio::buffer(&advice, sizeof(advice)));
  242. boost::asio::read(socketsPb[socket_no + 1], boost::asio::buffer(&cwts, sizeof(cwts)));
  243. cwt_L = cwts[0];
  244. cwt_R = cwts[1];
  245. cwt_L = cwt_L ^ advice_L ^ 1;
  246. cwt_R = cwt_R ^ advice_R;
  247. for (size_t j = 0; j < nodes_in_prev_layer; ++j)
  248. {
  249. t[curlayer][2 * j] = get_lsb(s[curlayer][2 * j]) ^ (cwt_L & t[1 - curlayer][j]);
  250. s[curlayer][2 * j] = clear_lsb(xor_if(s[curlayer][2 * j], CW[layer], !t[1 - curlayer][j]), 0b11);
  251. t[curlayer][(2 * j) + 1] = get_lsb(s[curlayer][(2 * j) + 1]) ^ (cwt_R & t[1 - curlayer][j]);
  252. s[curlayer][(2 * j) + 1] = clear_lsb(xor_if(s[curlayer][(2 * j) + 1], CW[layer], !t[1 - curlayer][j]), 0b11);
  253. }
  254. }
  255. __m128i Gamma = _mm_setzero_si128();
  256. for (size_t i = 0; i < to + 1; ++i)
  257. {
  258. Gamma[0] += output[i][0];
  259. Gamma[1] += output[i][1];
  260. }
  261. if (party)
  262. {
  263. Gamma[0] = -Gamma[0];
  264. Gamma[1] = -Gamma[1];
  265. }
  266. boost::asio::write(socketsPb[socket_no + 3], boost::asio::buffer(&Gamma, sizeof(Gamma)));
  267. boost::asio::read(socketsPb[socket_no + 3], boost::asio::buffer(&final_correction_word, sizeof(final_correction_word)));
  268. communication_cost += sizeof(Gamma);
  269. final_correction_word = Gamma; // final_correction_word + Gamma;
  270. } // dpf::__evalinterval
  271. void convert_shares(__m128i **output, int8_t **flags, size_t n_threads, size_t db_nitems, __m128i *final_correction_word, tcp::socket &sb, bool party)
  272. {
  273. for (size_t j = 0; j < db_nitems; ++j)
  274. {
  275. for (size_t k = 0; k < n_threads; ++k)
  276. {
  277. if (party)
  278. {
  279. output[k][j] = -output[k][j];
  280. flags[k][j] = -flags[k][j];
  281. }
  282. }
  283. #ifdef DEBUG
  284. int8_t out = flags[0][j];
  285. int8_t out_rec;
  286. boost::asio::write(sb, boost::asio::buffer(&out, sizeof(out)));
  287. boost::asio::read(sb, boost::asio::buffer(&out_rec, sizeof(out_rec)));
  288. out_rec = out_rec + out;
  289. if (out_rec != 0)
  290. std::cout << j << "(flags) --> " << (int)out_rec << std::endl
  291. << std::endl;
  292. __m128i out2 = output[0][j];
  293. __m128i out_rec2;
  294. boost::asio::write(sb, boost::asio::buffer(&out2, sizeof(out2)));
  295. boost::asio::read(sb, boost::asio::buffer(&out_rec2, sizeof(out_rec2)));
  296. out_rec2 = out_rec2 + out2;
  297. if (out_rec2[0] != 0)
  298. std::cout << j << "--> " << out_rec2[0] << std::endl;
  299. #endif
  300. }
  301. for (size_t i = 0; i < n_threads; ++i)
  302. {
  303. int64_t pm = 0;
  304. int64_t rb;
  305. arc4random_buf(&rb, sizeof(rb));
  306. for (size_t j = 0; j < db_nitems; ++j)
  307. {
  308. if (party)
  309. {
  310. if (flags[i][j] != 0)
  311. pm -= 1;
  312. }
  313. if (!party)
  314. {
  315. if (flags[i][j] != 0)
  316. pm += 1; // flags[0][j];
  317. }
  318. }
  319. }
  320. }
  321. void accept_conncections_from_Pb(boost::asio::io_context &io_context, std::vector<socket_t> &socketsPb, int port, size_t j)
  322. {
  323. tcp::acceptor acceptor_a(io_context, tcp::endpoint(tcp::v4(), port));
  324. tcp::socket sb_a(acceptor_a.accept());
  325. socketsPb[j] = std::move(sb_a);
  326. }
  327. int main(int argc, char *argv[])
  328. {
  329. boost::asio::io_context io_context;
  330. tcp::resolver resolver(io_context);
  331. const std::string host1 = argv[1];
  332. const size_t n_threads = atoi(argv[2]);
  333. const size_t number_of_sockets = 5 * n_threads;
  334. const size_t expo = atoi(argv[3]);
  335. const size_t maxRAM = atoi(argv[4]);
  336. const size_t db_nitems = 1ULL << expo;
  337. size_t RAM_needed_per_thread = 164 * db_nitems;
  338. std::cout << "RAM needed = " << n_threads*RAM_needed_per_thread << " bytes = " << n_threads*RAM_needed_per_thread/1073741824 << " GiB" << std::endl;
  339. std::cout << "RAM needed per thread = " << RAM_needed_per_thread << " bytes = " << (RAM_needed_per_thread>>30) << " GiB" << std::endl;
  340. size_t thread_per_batch = std::floor(double(maxRAM<<30)/RAM_needed_per_thread);
  341. if (thread_per_batch > n_threads) {
  342. thread_per_batch = n_threads;
  343. }
  344. std::cout << "thread_per_batch = " << thread_per_batch << std::endl;
  345. if (thread_per_batch < 1) {
  346. std::cout << "You need more RAM" << std::endl;
  347. exit(0);
  348. }
  349. size_t n_batches = std::ceil(double(n_threads)/thread_per_batch);
  350. std::cout << "n_batches = " << n_batches << std::endl;
  351. std::vector<socket_t> socketsPb;
  352. for (size_t j = 0; j < number_of_sockets + 1; ++j)
  353. {
  354. tcp::socket emptysocket(io_context);
  355. socketsPb.emplace_back(std::move(emptysocket));
  356. }
  357. socketsPb.reserve(number_of_sockets + 1);
  358. std::vector<int> ports;
  359. for (size_t j = 0; j < number_of_sockets; ++j)
  360. {
  361. int port = 6000;
  362. ports.push_back(port + j);
  363. }
  364. std::vector<int> ports2_0;
  365. for (size_t j = 0; j < number_of_sockets; ++j)
  366. {
  367. int port = 20000;
  368. ports2_0.push_back(port + j);
  369. }
  370. std::vector<int> ports2_1;
  371. for (size_t j = 0; j < number_of_sockets; ++j)
  372. {
  373. int port = 40000;
  374. ports2_1.push_back(port + j);
  375. }
  376. bool party;
  377. #if (PARTY == 0)
  378. party = false;
  379. for (size_t j = 0; j < number_of_sockets; ++j)
  380. {
  381. tcp::socket sb_a(io_context);
  382. boost::asio::connect(sb_a, resolver.resolve({host1, std::to_string(ports[j])}));
  383. socketsPb[j] = std::move(sb_a);
  384. }
  385. #else
  386. party = true;
  387. boost::asio::thread_pool pool2(number_of_sockets);
  388. for (size_t j = 0; j < number_of_sockets; ++j)
  389. {
  390. boost::asio::post(pool2, std::bind(accept_conncections_from_Pb, std::ref(io_context), std::ref(socketsPb), ports[j], j));
  391. }
  392. pool2.join();
  393. #endif
  394. __m128i *final_correction_word = (__m128i *)std::aligned_alloc(sizeof(__m256i), thread_per_batch * sizeof(__m128i));
  395. AES_KEY aeskey;
  396. __m128i **output = (__m128i **)malloc(sizeof(__m128i *) * thread_per_batch);
  397. int8_t **flags = (int8_t **)malloc(sizeof(uint8_t *) * thread_per_batch);
  398. for (size_t j = 0; j < thread_per_batch; ++j)
  399. {
  400. output[j] = (__m128i *)std::aligned_alloc(sizeof(node_t), db_nitems * sizeof(__m128i));
  401. flags[j] = (int8_t *)std::aligned_alloc(sizeof(node_t), db_nitems * sizeof(uint8_t));
  402. }
  403. const size_t bits_per_leaf = std::is_same<leaf_t, bool>::value ? 1 : sizeof(leaf_t) * CHAR_BIT;
  404. const bool is_packed = (sizeof(leaf_t) < sizeof(node_t));
  405. const size_t nodes_per_leaf = is_packed ? 1 : std::ceil(static_cast<double>(bits_per_leaf) / (sizeof(node_t) * CHAR_BIT));
  406. const size_t depth = std::ceil(std::log2(db_nitems));
  407. const size_t nbits = std::ceil(std::log2(db_nitems));
  408. const size_t nodes_in_interval = db_nitems - 1;
  409. auto start = std::chrono::steady_clock::now();
  410. #ifdef VERBOSE
  411. printf("n_threads = %zu\n\n", n_threads);
  412. #endif
  413. for(size_t iters = 0; iters < n_batches; ++iters)
  414. {
  415. if (n_batches > 1) {
  416. printf("Starting evalfull_mpc batch %lu / %lu\n", iters+1, n_batches);
  417. }
  418. uint8_t **target_share_read = new uint8_t *[thread_per_batch];
  419. generate_random_targets(target_share_read, thread_per_batch, party, expo);
  420. boost::asio::thread_pool pool(thread_per_batch);
  421. for (size_t j = 0; j < thread_per_batch; ++j)
  422. {
  423. boost::asio::post(pool, std::bind(evalfull_mpc, std::ref(nodes_per_leaf), std::ref(depth), std::ref(nbits), std::ref(nodes_in_interval),
  424. std::ref(aeskey), target_share_read[j], std::ref(socketsPb), 0, db_nitems - 1, output[j],
  425. flags[j], std::ref(final_correction_word[j]), party, 5 * j));
  426. }
  427. pool.join();
  428. convert_shares(output, flags, thread_per_batch, db_nitems, final_correction_word, socketsPb[0], party);
  429. }
  430. auto end = std::chrono::steady_clock::now();
  431. std::chrono::duration<double> elapsed_seconds = end - start;
  432. std::cout << "WallClockTime: " << elapsed_seconds.count() << " s" << std::endl;
  433. std::cout << "CommunicationCost: " << communication_cost << " bytes" << std::endl;
  434. if(!party)
  435. {
  436. char const *p0_filename0;
  437. p0_filename0 = "../duoram-online/preprocflags/party0_read_flags_b";
  438. int w0 = open(p0_filename0, O_WRONLY | O_CREAT, S_IWRITE | S_IREAD);
  439. int written = write(w0, flags[0], db_nitems * sizeof(flags[0][0]));
  440. if (written < 0) perror("Write error");
  441. close(w0);
  442. }
  443. else
  444. {
  445. char const *p0_filename0;
  446. p0_filename0 = "../duoram-online/preprocflags/party1_read_flags_b";
  447. int w0 = open(p0_filename0, O_WRONLY | O_CREAT, S_IWRITE | S_IREAD);
  448. int written = write(w0, flags[0], db_nitems * sizeof(flags[0][0]));
  449. if (written < 0) perror("Write error");
  450. close(w0);
  451. }
  452. return 0;
  453. }