/* This module generates and compares password hashes using SHA256 algorithms. * * If an intruder gets access to your system or uses a brute force attack, * salt will not provide much value. * IMPORTANT: DATA HASHES CANNOT BE "DECRYPTED" BACK TO PLAIN TEXT. * * Modified for Anope. * (C) 2003-2022 Anope Team * Contact us at team@anope.org * * Taken from InspIRCd (https://www.inspircd.org/), * see https://wiki.inspircd.org/Credits * * This program is free but copyrighted software; see * the file COPYING for details. */ /* FIPS 180-2 SHA-224/256/384/512 implementation * Last update: 05/23/2005 * Issue date: 04/30/2005 * * Copyright (C) 2005 Olivier Gay * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "module.h" #include "modules/encryption.h" static const unsigned SHA256_DIGEST_SIZE = 256 / 8; static const unsigned SHA256_BLOCK_SIZE = 512 / 8; inline static uint32_t SHFR(uint32_t x, uint32_t n) { return x >> n; } inline static uint32_t ROTR(uint32_t x, uint32_t n) { return (x >> n) | (x << ((sizeof(x) << 3) - n)); } inline static uint32_t CH(uint32_t x, uint32_t y, uint32_t z) { return (x & y) ^ (~x & z); } inline static uint32_t MAJ(uint32_t x, uint32_t y, uint32_t z) { return (x & y) ^ (x & z) ^ (y & z); } inline static uint32_t SHA256_F1(uint32_t x) { return ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22); } inline static uint32_t SHA256_F2(uint32_t x) { return ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25); } inline static uint32_t SHA256_F3(uint32_t x) { return ROTR(x, 7) ^ ROTR(x, 18) ^ SHFR(x, 3); } inline static uint32_t SHA256_F4(uint32_t x) { return ROTR(x, 17) ^ ROTR(x, 19) ^ SHFR(x, 10); } inline static void UNPACK32(unsigned x, unsigned char *str) { str[3] = static_cast(x); str[2] = static_cast(x >> 8); str[1] = static_cast(x >> 16); str[0] = static_cast(x >> 24); } inline static void PACK32(unsigned char *str, uint32_t &x) { x = static_cast(str[3]) | static_cast(str[2]) << 8 | static_cast(str[1]) << 16 | static_cast(str[0]) << 24; } /* Macros used for loops unrolling */ inline static void SHA256_SCR(uint32_t w[64], int i) { w[i] = SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16]; } static const uint32_t sha256_h0[8] = { 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 }; static const uint32_t sha256_k[64] = { 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 }; /** An sha256 context */ class SHA256Context : public Encryption::Context { void Transform(unsigned char *message, unsigned block_nb) { uint32_t w[64], wv[8]; unsigned char *sub_block; for (unsigned i = 1; i <= block_nb; ++i) { int j; sub_block = message + ((i - 1) << 6); for (j = 0; j < 16; ++j) PACK32(&sub_block[j << 2], w[j]); for (j = 16; j < 64; ++j) SHA256_SCR(w, j); for (j = 0; j < 8; ++j) wv[j] = this->h[j]; for (j = 0; j < 64; ++j) { uint32_t t1 = wv[7] + SHA256_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) + sha256_k[j] + w[j]; uint32_t t2 = SHA256_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]); wv[7] = wv[6]; wv[6] = wv[5]; wv[5] = wv[4]; wv[4] = wv[3] + t1; wv[3] = wv[2]; wv[2] = wv[1]; wv[1] = wv[0]; wv[0] = t1 + t2; } for (j = 0; j < 8; ++j) this->h[j] += wv[j]; } } unsigned tot_len; unsigned len; unsigned char block[2 * SHA256_BLOCK_SIZE]; uint32_t h[8]; unsigned char digest[SHA256_DIGEST_SIZE]; public: SHA256Context(Encryption::IV *iv) { if (iv != NULL) { if (iv->second != 8) throw CoreException("Invalid IV size"); for (int i = 0; i < 8; ++i) this->h[i] = iv->first[i]; } else for (int i = 0; i < 8; ++i) this->h[i] = sha256_h0[i]; this->tot_len = 0; this->len = 0; memset(this->block, 0, sizeof(this->block)); memset(this->digest, 0, sizeof(this->digest)); } void Update(const unsigned char *message, size_t mlen) anope_override { unsigned tmp_len = SHA256_BLOCK_SIZE - this->len, rem_len = mlen < tmp_len ? mlen : tmp_len; memcpy(&this->block[this->len], message, rem_len); if (this->len + mlen < SHA256_BLOCK_SIZE) { this->len += mlen; return; } unsigned new_len = mlen - rem_len, block_nb = new_len / SHA256_BLOCK_SIZE; unsigned char *shifted_message = new unsigned char[mlen - rem_len]; memcpy(shifted_message, message + rem_len, mlen - rem_len); this->Transform(this->block, 1); this->Transform(shifted_message, block_nb); rem_len = new_len % SHA256_BLOCK_SIZE; memcpy(this->block, &shifted_message[block_nb << 6], rem_len); delete [] shifted_message; this->len = rem_len; this->tot_len += (block_nb + 1) << 6; } void Finalize() anope_override { unsigned block_nb = 1 + ((SHA256_BLOCK_SIZE - 9) < (this->len % SHA256_BLOCK_SIZE)); unsigned len_b = (this->tot_len + this->len) << 3; unsigned pm_len = block_nb << 6; memset(this->block + this->len, 0, pm_len - this->len); this->block[this->len] = 0x80; UNPACK32(len_b, this->block + pm_len - 4); this->Transform(this->block, block_nb); for (int i = 0 ; i < 8; ++i) UNPACK32(this->h[i], &this->digest[i << 2]); } Encryption::Hash GetFinalizedHash() anope_override { Encryption::Hash hash; hash.first = this->digest; hash.second = SHA256_DIGEST_SIZE; return hash; } }; class SHA256Provider : public Encryption::Provider { public: SHA256Provider(Module *creator) : Encryption::Provider(creator, "sha256") { } Encryption::Context *CreateContext(Encryption::IV *iv) anope_override { return new SHA256Context(iv); } Encryption::IV GetDefaultIV() anope_override { Encryption::IV iv; iv.first = sha256_h0; iv.second = sizeof(sha256_h0) / sizeof(uint32_t); return iv; } }; class ESHA256 : public Module { SHA256Provider sha256provider; unsigned iv[8]; bool use_iv; /* initializes the IV with a new random value */ void NewRandomIV() { for (int i = 0; i < 8; ++i) iv[i] = static_cast(rand()); } /* returns the IV as base64-encrypted string */ Anope::string GetIVString() { char buf[33]; for (int i = 0; i < 8; ++i) UNPACK32(iv[i], reinterpret_cast(&buf[i << 2])); buf[32] = '\0'; return Anope::Hex(buf, 32); } /* splits the appended IV from the password string so it can be used for the next encryption */ /* password format: :: */ void GetIVFromPass(const Anope::string &password) { size_t pos = password.find(':'); Anope::string buf = password.substr(password.find(':', pos + 1) + 1, password.length()); char buf2[33]; Anope::Unhex(buf, buf2, sizeof(buf2)); for (int i = 0 ; i < 8; ++i) PACK32(reinterpret_cast(&buf2[i << 2]), iv[i]); } public: ESHA256(const Anope::string &modname, const Anope::string &creator) : Module(modname, creator, ENCRYPTION | VENDOR), sha256provider(this) { use_iv = false; } EventReturn OnEncrypt(const Anope::string &src, Anope::string &dest) anope_override { if (!use_iv) NewRandomIV(); else use_iv = false; Encryption::IV initialization(this->iv, 8); SHA256Context ctx(&initialization); ctx.Update(reinterpret_cast(src.c_str()), src.length()); ctx.Finalize(); Encryption::Hash hash = ctx.GetFinalizedHash(); std::stringstream buf; buf << "sha256:" << Anope::Hex(reinterpret_cast(hash.first), hash.second) << ":" << GetIVString(); Log(LOG_DEBUG_2) << "(enc_sha256) hashed password from [" << src << "] to [" << buf.str() << " ]"; dest = buf.str(); return EVENT_ALLOW; } void OnCheckAuthentication(User *, IdentifyRequest *req) anope_override { const NickAlias *na = NickAlias::Find(req->GetAccount()); if (na == NULL) return; NickCore *nc = na->nc; size_t pos = nc->pass.find(':'); if (pos == Anope::string::npos) return; Anope::string hash_method(nc->pass.begin(), nc->pass.begin() + pos); if (!hash_method.equals_cs("sha256")) return; GetIVFromPass(nc->pass); use_iv = true; Anope::string buf; this->OnEncrypt(req->GetPassword(), buf); if (nc->pass.equals_cs(buf)) { /* if we are NOT the first module in the list, * we want to re-encrypt the pass with the new encryption */ if (ModuleManager::FindFirstOf(ENCRYPTION) != this) Anope::Encrypt(req->GetPassword(), nc->pass); req->Success(this); } } }; MODULE_INIT(ESHA256)