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Diffstat (limited to 'client/cpp/rappor_sim.cc')
| -rw-r--r-- | client/cpp/rappor_sim.cc | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/client/cpp/rappor_sim.cc b/client/cpp/rappor_sim.cc new file mode 100644 index 0000000..6e91630 --- /dev/null +++ b/client/cpp/rappor_sim.cc @@ -0,0 +1,229 @@ +// Copyright 2014 Google Inc. All rights reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include <stdio.h> +#include <time.h> // time + +#include <cassert> // assert +#include <cstdlib> // strtol, strtof +#include <iostream> +#include <vector> + +#include "encoder.h" +#include "libc_rand_impl.h" +#include "unix_kernel_rand_impl.h" +#include "openssl_hash_impl.h" + +// Like atoi, but with basic (not exhaustive) error checking. +bool StringToInt(const char* s, int* result) { + bool ok = true; + char* end; // mutated by strtol + + *result = strtol(s, &end, 10); // base 10 + // If strol didn't consume any characters, it failed. + if (end == s) { + ok = false; + } + return ok; +} + +// Like atof, but with basic (not exhaustive) error checking. +bool StringToFloat(const char* s, float* result) { + bool ok = true; + char* end; // mutated by strtof + + *result = strtof(s, &end); + // If strof didn't consume any characters, it failed. + if (end == s) { + ok = false; + } + return ok; +} + +// Copy a report into a string, which can go in a protobuf. +void BitsToString(rappor::Bits b, std::string* output, int num_bytes) { + output->assign(num_bytes, '\0'); + for (int i = 0; i < num_bytes; ++i) { + // "little endian" string + (*output)[i] = b & 0xFF; // last byte + b >>= 8; + } +} + +// Print a report, with the most significant bit first. +void PrintBitString(const std::string& s) { + for (int i = s.size() - 1; i >= 0; --i) { + unsigned char byte = s[i]; + for (int j = 7; j >= 0; --j) { + bool bit = byte & (1 << j); + std::cout << (bit ? "1" : "0"); + } + } +} + +int main(int argc, char** argv) { + if (argc != 7) { + rappor::log( + "Usage: rappor_encode <num bits> <num hashes> <num cohorts> p q f"); + exit(1); + } + + int num_bits, num_hashes, num_cohorts; + float prob_p, prob_q, prob_f; + + bool ok1 = StringToInt(argv[1], &num_bits); + bool ok2 = StringToInt(argv[2], &num_hashes); + bool ok3 = StringToInt(argv[3], &num_cohorts); + + bool ok4 = StringToFloat(argv[4], &prob_p); + bool ok5 = StringToFloat(argv[5], &prob_q); + bool ok6 = StringToFloat(argv[6], &prob_f); + + if (!ok1) { + rappor::log("Invalid number of bits: '%s'", argv[1]); + exit(1); + } + if (!ok2) { + rappor::log("Invalid number of hashes: '%s'", argv[2]); + exit(1); + } + if (!ok3) { + rappor::log("Invalid number of cohorts: '%s'", argv[3]); + exit(1); + } + if (!ok4) { + rappor::log("Invalid float p: '%s'", argv[4]); + exit(1); + } + if (!ok5) { + rappor::log("Invalid float q: '%s'", argv[5]); + exit(1); + } + if (!ok6) { + rappor::log("Invalid float f: '%s'", argv[6]); + exit(1); + } + + rappor::Params params(num_bits, num_hashes, num_cohorts, prob_f, prob_p, + prob_q); + + //rappor::log("k: %d, h: %d, m: %d", params.num_bits(), params.num_hashes(), params.num_cohorts()); + //rappor::log("f: %f, p: %f, q: %f", prob_f, prob_p, prob_q); + + int num_bytes = params.num_bits() / 8; + + // TODO: Add a flag for + // - -r libc / kernel + // - -c openssl / nacl crpto + + rappor::IrrRandInterface* irr_rand; + if (false) { + FILE* fp = fopen("/dev/urandom", "r"); + irr_rand = new rappor::UnixKernelRand(fp); + } else { + int seed = time(NULL); + srand(seed); // seed with nanoseconds + irr_rand = new rappor::LibcRand(); + } + + std::string line; + + // CSV header + std::cout << "client,cohort,bloom,prr,irr\n"; + + // Consume header line + std::getline(std::cin, line); + if (line != "client,cohort,value") { + rappor::log("Expected CSV header 'client,cohort,value'"); + return 1; + } + + while (true) { + std::getline(std::cin, line); // no trailing newline + // rappor::log("Got line %s", line.c_str()); + + if (line.empty()) { + break; // EOF + } + + size_t comma1_pos = line.find(','); + if (comma1_pos == std::string::npos) { + rappor::log("Expected , in line '%s'", line.c_str()); + return 1; + } + size_t comma2_pos = line.find(',', comma1_pos + 1); + if (comma2_pos == std::string::npos) { + rappor::log("Expected second , in line '%s'", line.c_str()); + return 1; + } + + // The C++ API substr(pos, length) not (pos, end) + + // everything before comma + std::string client_str = line.substr(0, comma1_pos); + // everything between first and second comma. + // TODO(andychu): Remove unused second column. + std::string unused = line.substr(comma1_pos + 1, comma2_pos-comma1_pos); + // everything after + std::string value = line.substr(comma2_pos + 1); + + rappor::Deps deps(rappor::Md5, client_str /*client_secret*/, + rappor::HmacSha256, *irr_rand); + + // For now, construct a new encoder every time. We could construct one for + // each client. We are simulating many clients reporting the same metric, + // so the encoder ID is constant. + rappor::Encoder e("metric-name", params, deps); + + // rappor::log("CLIENT %s VALUE %s COHORT %d", client_str.c_str(), + // value.c_str(), cohort); + + rappor::Bits bloom; + rappor::Bits prr; + rappor::Bits irr; + bool ok = e._EncodeStringInternal(value, &bloom, &prr, &irr); + + // NOTE: Are there really encoding errors? + if (!ok) { + rappor::log("Error encoding string %s", line.c_str()); + break; + } + + std::string bloom_str; + BitsToString(bloom, &bloom_str, num_bytes); + + std::string prr_str; + BitsToString(prr, &prr_str, num_bytes); + + std::string irr_str; + BitsToString(irr, &irr_str, num_bytes); + + // Output CSV row. + + std::cout << client_str; + std::cout << ','; + std::cout << e.cohort(); // cohort the encoder assigned + std::cout << ','; + PrintBitString(bloom_str); + std::cout << ','; + PrintBitString(prr_str); + std::cout << ','; + PrintBitString(irr_str); + + std::cout << "\n"; + } + + // Cleanup + delete irr_rand; +} |