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Commit message (Collapse)AuthorAge
* Client eventmanager refactor (#7179)Loïc Blot2018-03-30
| | | | | | | | | | | | | | | | | | | | | * Drop EventManager from GameDef & do some client cleanups * EventManager is only used by Client. Don't expose it on Server & GameDef for nothing * Drop Client::event() in favor of direct calls to getEventManager * Cleanup some event put from new + put to put(new) * MtEvent: add Type(u8) enum * This will enhance event performance & ensure stricter type * Drop MtEvent::checkIs (unused) * clang-tidy reported fixes * Code style * Move event_manager.h to the client directory as it's only used by client Add EventManager unittests + switch to unordered_map as order is not important here Drop a unused function
* Cleanup sound manager class (#7158)Loïc Blot2018-03-24
| | | | | | | | | | * Cleanup sound manager client * Use some const refs * Use auto on iterators * Drop unused parameters * Move sound_openal.* to client folder * Move sound.cpp + OnDemandSoundFetcher to client/ folder + reorganize includes properly
* Node definition manager refactor (#7016)Dániel Juhász2018-02-10
| | | | | | | | | * Rename IWritableNodeDefManager to NodeDefManager * Make INodeDefManager functions const * Use "const *NodeDefManager" instead of "*INodeDefManager" * Remove unused INodeDefManager class * Merge NodeDefManager and CNodeDefManager * Document NodeDefManager
* Implement mod communication channels (#6351)Loïc Blot2017-09-26
| | | | | | | | | | Implement network communication for channels * Implement ModChannel manager server side to route incoming messages from clients to other clients * Add signal handler switch on client & ModChannelMgr on client to handle channels * Add Lua API bindings + client packet sending + unittests * Implement server message sending * Add callback from received message handler to Lua API using registration method
* C++ modernize: Pragma once (#6264)Loïc Blot2017-08-17
| | | | * Migrate cpp headers to pragma once
* Add ModStorageAPI to client side modding (#5396)Loïc Blot2017-03-16
| | | mod storage is located into user_path / client / mod_storage
* Add `get_wielded_item`red-0012017-03-13
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* [CSM] Client side moddingLoic Blot2017-03-13
| | | | | | | | | | * rename GameScripting to ServerScripting * Make getBuiltinLuaPath static serverside * Add on_shutdown callback * Add on_receiving_chat_message & on_sending_chat_message callbacks * ScriptApiBase: use IGameDef instead of Server This permits to share common attribute between client & server * Enable mod security in client side modding without conditions
* Environment & IGameDef code refactoring (#4985)Ner'zhul2017-01-09
| | | | | | | | | | | | | | | | | | | | | * Environment code refactoring * Cleanup includes & class declarations in client & server environment to improve build speed * ServerEnvironment::m_gamedef is now a pointer to Server instead of IGameDef, permitting to cleanup many casts. * Cleanup IGameDef * Move ITextureSource* IGameDef::getTextureSource() to Client only. * Also move ITextureSource *IGameDef::tsrc() helper * drop getShaderSource, getSceneManager, getSoundManager & getCamera abstract call * drop unused emerge() call * cleanup server unused functions (mentionned before) * Drop one unused parameter from ContentFeatures::updateTextures * move checkLocalPrivilege to Client * Remove some unnecessary casts * create_formspec_menu: remove IWritableTextureSource pointer, as client already knows it * Fix some comments * Change required IGameDef to Server/Client pointers * Previous change that game.cpp sometimes calls functions with Client + InventoryManager + IGameDef in same functions but it's the same objects * Remove duplicate Client pointer in GUIFormSpecMenu::GUIFormSpecMenu * drop ClientMap::sectorWasDrawn which is unused
* Move object nametags to cameraRealBadAngel2016-02-18
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* Biomes: Remove referenced biomes from Decorations on clearkwolekr2015-04-16
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* Clean up rollbackShadowNinja2014-11-19
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* Recalculate normals for cached meshes.RealBadAngel2014-10-21
| | | | | | Check if mesh is here before adding to meshcollector. Fix deleting the meshes.
* Create new instance of mesh every time it's required (Solves #703)Perttu Ahola2014-01-06
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* Update Copyright YearsSfan52013-02-24
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* Change Minetest-c55 to MinetestPilzAdam2013-02-24
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* ShaderSource and silly example shadersKahrl2012-12-02
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* Experimental-ish rollback functionalityPerttu Ahola2012-07-27
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* Switch the license to be LGPLv2/later, with small parts still remaining as ↵Perttu Ahola2012-06-05
| | | | GPLv2/later, by agreement of major contributors
* Add 'fly' and 'fast' privileges and the underlying privileges-to-client systemPerttu Ahola2012-03-31
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* Add event manager and use it to trigger soundsPerttu Ahola2012-03-24
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* celeron55's sound system initial frameworkPerttu Ahola2012-03-24
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* Node placement / mineral / serialization / iron freq / node_dig callbackKahrl2012-01-22
| | | | | | | | - Node placement code moved to Lua - Mineral system removed (added default:stone_with_coal and default:stone_with_iron). - MapBlock and MapNode serialization updated. - Mapgen: Frequency of iron increased. - node_dig callback and related changes.
* The huge item definition and item namespace unification patch (itemdef), see ↵Kahrl2012-01-12
| | | | http://c55.me/minetest/wiki/doku.php?id=changes:itemdef
* CraftItem rework and Lua interfaceKahrl2011-11-29
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* Crafting definition in scriptsPerttu Ahola2011-11-29
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* Node definition namesPerttu Ahola2011-11-29
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* GameDef compilesPerttu Ahola2011-11-29
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* Create framework for getting rid of global definitions of ↵Perttu Ahola2011-11-29
node/tool/item/whatever types
03' href='#n603'>603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040
/*
 * Secure Remote Password 6a implementation
 * https://github.com/est31/csrp-gmp
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2010, 2013 Tom Cocagne, 2015 est31 <MTest31@outlook.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

// clang-format off

#include <cstddef>

#ifdef WIN32
	#include <windows.h>
	#include <wincrypt.h>
#else
	#include <ctime>

#endif
// clang-format on

#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <cstdint>

#include <config.h>

#if USE_SYSTEM_GMP
	#include <gmp.h>
#else
	#include <mini-gmp.h>
#endif

#include <util/sha2.h>

#include "srp.h"
//#define CSRP_USE_SHA1
#define CSRP_USE_SHA256

#define srp_dbg_data(data, datalen, prevtext) ;
/*void srp_dbg_data(unsigned char * data, size_t datalen, char * prevtext)
{
	printf(prevtext);
	size_t i;
	for (i = 0; i < datalen; i++)
	{
		printf("%02X", data[i]);
	}
	printf("\n");
}*/

static int g_initialized = 0;

#define RAND_BUFF_MAX 128
static unsigned int g_rand_idx;
static unsigned char g_rand_buff[RAND_BUFF_MAX];

void *(*srp_alloc)(size_t) = &malloc;
void *(*srp_realloc)(void *, size_t) = &realloc;
void (*srp_free)(void *) = &free;

// clang-format off
void srp_set_memory_functions(
		void *(*new_srp_alloc)(size_t),
		void *(*new_srp_realloc)(void *, size_t),
		void (*new_srp_free)(void *))
{
	srp_alloc = new_srp_alloc;
	srp_realloc = new_srp_realloc;
	srp_free = new_srp_free;
}
// clang-format on

typedef struct {
	mpz_t N;
	mpz_t g;
} NGConstant;

struct NGHex {
	const char *n_hex;
	const char *g_hex;
};

/* All constants here were pulled from Appendix A of RFC 5054 */
static struct NGHex global_Ng_constants[] = {
	{/* 1024 */
		"EEAF0AB9ADB38DD69C33F80AFA8FC5E86072618775FF3C0B9EA2314C"
		"9C256576D674DF7496EA81D3383B4813D692C6E0E0D5D8E250B98BE4"
		"8E495C1D6089DAD15DC7D7B46154D6B6CE8EF4AD69B15D4982559B29"
		"7BCF1885C529F566660E57EC68EDBC3C05726CC02FD4CBF4976EAA9A"
		"FD5138FE8376435B9FC61D2FC0EB06E3",
		"2"},
	{/* 2048 */
		"AC6BDB41324A9A9BF166DE5E1389582FAF72B6651987EE07FC319294"
		"3DB56050A37329CBB4A099ED8193E0757767A13DD52312AB4B03310D"
		"CD7F48A9DA04FD50E8083969EDB767B0CF6095179A163AB3661A05FB"
		"D5FAAAE82918A9962F0B93B855F97993EC975EEAA80D740ADBF4FF74"
		"7359D041D5C33EA71D281E446B14773BCA97B43A23FB801676BD207A"
		"436C6481F1D2B9078717461A5B9D32E688F87748544523B524B0D57D"
		"5EA77A2775D2ECFA032CFBDBF52FB3786160279004E57AE6AF874E73"
		"03CE53299CCC041C7BC308D82A5698F3A8D0C38271AE35F8E9DBFBB6"
		"94B5C803D89F7AE435DE236D525F54759B65E372FCD68EF20FA7111F"
		"9E4AFF73",
		"2"},
	{/* 4096 */
		"FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E08"
		"8A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B"
		"302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9"
		"A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE6"
		"49286651ECE45B3DC2007CB8A163BF0598DA48361C55D39A69163FA8"
		"FD24CF5F83655D23DCA3AD961C62F356208552BB9ED529077096966D"
		"670C354E4ABC9804F1746C08CA18217C32905E462E36CE3BE39E772C"
		"180E86039B2783A2EC07A28FB5C55DF06F4C52C9DE2BCBF695581718"
		"3995497CEA956AE515D2261898FA051015728E5A8AAAC42DAD33170D"
		"04507A33A85521ABDF1CBA64ECFB850458DBEF0A8AEA71575D060C7D"
		"B3970F85A6E1E4C7ABF5AE8CDB0933D71E8C94E04A25619DCEE3D226"
		"1AD2EE6BF12FFA06D98A0864D87602733EC86A64521F2B18177B200C"
		"BBE117577A615D6C770988C0BAD946E208E24FA074E5AB3143DB5BFC"
		"E0FD108E4B82D120A92108011A723C12A787E6D788719A10BDBA5B26"
		"99C327186AF4E23C1A946834B6150BDA2583E9CA2AD44CE8DBBBC2DB"
		"04DE8EF92E8EFC141FBECAA6287C59474E6BC05D99B2964FA090C3A2"
		"233BA186515BE7ED1F612970CEE2D7AFB81BDD762170481CD0069127"
		"D5B05AA993B4EA988D8FDDC186FFB7DC90A6C08F4DF435C934063199"
		"FFFFFFFFFFFFFFFF",
		"5"},
	{/* 8192 */
		"FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E08"
		"8A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B"
		"302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9"
		"A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE6"
		"49286651ECE45B3DC2007CB8A163BF0598DA48361C55D39A69163FA8"
		"FD24CF5F83655D23DCA3AD961C62F356208552BB9ED529077096966D"
		"670C354E4ABC9804F1746C08CA18217C32905E462E36CE3BE39E772C"
		"180E86039B2783A2EC07A28FB5C55DF06F4C52C9DE2BCBF695581718"
		"3995497CEA956AE515D2261898FA051015728E5A8AAAC42DAD33170D"
		"04507A33A85521ABDF1CBA64ECFB850458DBEF0A8AEA71575D060C7D"
		"B3970F85A6E1E4C7ABF5AE8CDB0933D71E8C94E04A25619DCEE3D226"
		"1AD2EE6BF12FFA06D98A0864D87602733EC86A64521F2B18177B200C"
		"BBE117577A615D6C770988C0BAD946E208E24FA074E5AB3143DB5BFC"
		"E0FD108E4B82D120A92108011A723C12A787E6D788719A10BDBA5B26"
		"99C327186AF4E23C1A946834B6150BDA2583E9CA2AD44CE8DBBBC2DB"
		"04DE8EF92E8EFC141FBECAA6287C59474E6BC05D99B2964FA090C3A2"
		"233BA186515BE7ED1F612970CEE2D7AFB81BDD762170481CD0069127"
		"D5B05AA993B4EA988D8FDDC186FFB7DC90A6C08F4DF435C934028492"
		"36C3FAB4D27C7026C1D4DCB2602646DEC9751E763DBA37BDF8FF9406"
		"AD9E530EE5DB382F413001AEB06A53ED9027D831179727B0865A8918"
		"DA3EDBEBCF9B14ED44CE6CBACED4BB1BDB7F1447E6CC254B33205151"
		"2BD7AF426FB8F401378CD2BF5983CA01C64B92ECF032EA15D1721D03"
		"F482D7CE6E74FEF6D55E702F46980C82B5A84031900B1C9E59E7C97F"
		"BEC7E8F323A97A7E36CC88BE0F1D45B7FF585AC54BD407B22B4154AA"
		"CC8F6D7EBF48E1D814CC5ED20F8037E0A79715EEF29BE32806A1D58B"
		"B7C5DA76F550AA3D8A1FBFF0EB19CCB1A313D55CDA56C9EC2EF29632"
		"387FE8D76E3C0468043E8F663F4860EE12BF2D5B0B7474D6E694F91E"
		"6DBE115974A3926F12FEE5E438777CB6A932DF8CD8BEC4D073B931BA"
		"3BC832B68D9DD300741FA7BF8AFC47ED2576F6936BA424663AAB639C"
		"5AE4F5683423B4742BF1C978238F16CBE39D652DE3FDB8BEFC848AD9"
		"22222E04A4037C0713EB57A81A23F0C73473FC646CEA306B4BCBC886"
		"2F8385DDFA9D4B7FA2C087E879683303ED5BDD3A062B3CF5B3A278A6"
		"6D2A13F83F44F82DDF310EE074AB6A364597E899A0255DC164F31CC5"
		"0846851DF9AB48195DED7EA1B1D510BD7EE74D73FAF36BC31ECFA268"
		"359046F4EB879F924009438B481C6CD7889A002ED5EE382BC9190DA6"
		"FC026E479558E4475677E9AA9E3050E2765694DFC81F56E880B96E71"
		"60C980DD98EDD3DFFFFFFFFFFFFFFFFF",
		"13"},
	{0, 0} /* null sentinel */
};

static void delete_ng(NGConstant *ng)
{
	if (ng) {
		mpz_clear(ng->N);
		mpz_clear(ng->g);
		srp_free(ng);
	}
}

static NGConstant *new_ng(SRP_NGType ng_type, const char *n_hex, const char *g_hex)
{
	NGConstant *ng = (NGConstant *)srp_alloc(sizeof(NGConstant));

	if (!ng) return 0;

	mpz_init(ng->N);
	mpz_init(ng->g);

	if (ng_type != SRP_NG_CUSTOM) {
		n_hex = global_Ng_constants[ng_type].n_hex;
		g_hex = global_Ng_constants[ng_type].g_hex;
	}

	int rv = 0;
	rv = mpz_set_str(ng->N, n_hex, 16);
	rv = rv | mpz_set_str(ng->g, g_hex, 16);

	if (rv) {
		delete_ng(ng);
		return 0;
	}

	return ng;
}

typedef union {
	SHA_CTX sha;
	SHA256_CTX sha256;
	// SHA512_CTX sha512;
} HashCTX;

struct SRPVerifier {
	SRP_HashAlgorithm hash_alg;
	NGConstant *ng;

	char *username;
	unsigned char *bytes_B;
	int authenticated;

	unsigned char M[SHA512_DIGEST_LENGTH];
	unsigned char H_AMK[SHA512_DIGEST_LENGTH];
	unsigned char session_key[SHA512_DIGEST_LENGTH];
};

struct SRPUser {
	SRP_HashAlgorithm hash_alg;
	NGConstant *ng;

	mpz_t a;
	mpz_t A;
	mpz_t S;

	unsigned char *bytes_A;
	int authenticated;

	char *username;
	char *username_verifier;
	unsigned char *password;
	size_t password_len;

	unsigned char M[SHA512_DIGEST_LENGTH];
	unsigned char H_AMK[SHA512_DIGEST_LENGTH];
	unsigned char session_key[SHA512_DIGEST_LENGTH];
};

// clang-format off
static int hash_init(SRP_HashAlgorithm alg, HashCTX *c)
{
	switch (alg) {
#ifdef CSRP_USE_SHA1
		case SRP_SHA1: return SHA1_Init(&c->sha);
#endif
		/*
		case SRP_SHA224: return SHA224_Init(&c->sha256);
		*/
#ifdef CSRP_USE_SHA256
		case SRP_SHA256: return SHA256_Init(&c->sha256);
#endif
		/*
		case SRP_SHA384: return SHA384_Init(&c->sha512);
		case SRP_SHA512: return SHA512_Init(&c->sha512);
		*/
		default: return -1;
	};
}
static int hash_update( SRP_HashAlgorithm alg, HashCTX *c, const void *data, size_t len )
{
	switch (alg) {
#ifdef CSRP_USE_SHA1
		case SRP_SHA1: return SHA1_Update(&c->sha, data, len);
#endif
		/*
		case SRP_SHA224: return SHA224_Update(&c->sha256, data, len);
		*/
#ifdef CSRP_USE_SHA256
		case SRP_SHA256: return SHA256_Update(&c->sha256, data, len);
#endif
		/*
		case SRP_SHA384: return SHA384_Update(&c->sha512, data, len);
		case SRP_SHA512: return SHA512_Update(&c->sha512, data, len);
		*/
		default: return -1;
	};
}
static int hash_final( SRP_HashAlgorithm alg, HashCTX *c, unsigned char *md )
{
	switch (alg) {
#ifdef CSRP_USE_SHA1
		case SRP_SHA1: return SHA1_Final(md, &c->sha);
#endif
		/*
		case SRP_SHA224: return SHA224_Final(md, &c->sha256);
		*/
#ifdef CSRP_USE_SHA256
		case SRP_SHA256: return SHA256_Final(md, &c->sha256);
#endif
		/*
		case SRP_SHA384: return SHA384_Final(md, &c->sha512);
		case SRP_SHA512: return SHA512_Final(md, &c->sha512);
		*/
		default: return -1;
	};
}
static unsigned char *hash(SRP_HashAlgorithm alg, const unsigned char *d, size_t n, unsigned char *md)
{
	switch (alg) {
#ifdef CSRP_USE_SHA1
		case SRP_SHA1: return SHA1(d, n, md);
#endif
		/*
		case SRP_SHA224: return SHA224( d, n, md );
		*/
#ifdef CSRP_USE_SHA256
		case SRP_SHA256: return SHA256(d, n, md);
#endif
		/*
		case SRP_SHA384: return SHA384( d, n, md );
		case SRP_SHA512: return SHA512( d, n, md );
		*/
		default: return 0;
	};
}
static size_t hash_length(SRP_HashAlgorithm alg)
{
	switch (alg) {
#ifdef CSRP_USE_SHA1
		case SRP_SHA1: return SHA_DIGEST_LENGTH;
#endif
		/*
		case SRP_SHA224: return SHA224_DIGEST_LENGTH;
		*/
#ifdef CSRP_USE_SHA256
		case SRP_SHA256: return SHA256_DIGEST_LENGTH;
#endif
		/*
		case SRP_SHA384: return SHA384_DIGEST_LENGTH;
		case SRP_SHA512: return SHA512_DIGEST_LENGTH;
		*/
		default: return -1;
	};
}
// clang-format on

inline static int mpz_num_bytes(const mpz_t op)
{
	return (mpz_sizeinbase(op, 2) + 7) / 8;
}

inline static void mpz_to_bin(const mpz_t op, unsigned char *to)
{
	mpz_export(to, NULL, 1, 1, 1, 0, op);
}

inline static void mpz_from_bin(const unsigned char *s, size_t len, mpz_t ret)
{
	mpz_import(ret, len, 1, 1, 1, 0, s);
}

// set op to (op1 * op2) mod d, using tmp for the calculation
inline static void mpz_mulm(
	mpz_t op, const mpz_t op1, const mpz_t op2, const mpz_t d, mpz_t tmp)
{
	mpz_mul(tmp, op1, op2);
	mpz_mod(op, tmp, d);
}

// set op to (op1 + op2) mod d, using tmp for the calculation
inline static void mpz_addm(
	mpz_t op, const mpz_t op1, const mpz_t op2, const mpz_t d, mpz_t tmp)
{
	mpz_add(tmp, op1, op2);
	mpz_mod(op, tmp, d);
}

// set op to (op1 - op2) mod d, using tmp for the calculation
inline static void mpz_subm(
	mpz_t op, const mpz_t op1, const mpz_t op2, const mpz_t d, mpz_t tmp)
{
	mpz_sub(tmp, op1, op2);
	mpz_mod(op, tmp, d);
}

static SRP_Result H_nn(
	mpz_t result, SRP_HashAlgorithm alg, const mpz_t N, const mpz_t n1, const mpz_t n2)
{
	unsigned char buff[SHA512_DIGEST_LENGTH];
	size_t len_N = mpz_num_bytes(N);
	size_t len_n1 = mpz_num_bytes(n1);
	size_t len_n2 = mpz_num_bytes(n2);
	size_t nbytes = len_N + len_N;
	unsigned char *bin = (unsigned char *)srp_alloc(nbytes);
	if (!bin) return SRP_ERR;
	if (len_n1 > len_N || len_n2 > len_N) {
		srp_free(bin);
		return SRP_ERR;
	}
	memset(bin, 0, nbytes);
	mpz_to_bin(n1, bin + (len_N - len_n1));
	mpz_to_bin(n2, bin + (len_N + len_N - len_n2));
	hash(alg, bin, nbytes, buff);
	srp_free(bin);
	mpz_from_bin(buff, hash_length(alg), result);
	return SRP_OK;
}

static SRP_Result H_ns(mpz_t result, SRP_HashAlgorithm alg, const unsigned char *n,
	size_t len_n, const unsigned char *bytes, uint32_t len_bytes)
{
	unsigned char buff[SHA512_DIGEST_LENGTH];
	size_t nbytes = len_n + len_bytes;
	unsigned char *bin = (unsigned char *)srp_alloc(nbytes);
	if (!bin) return SRP_ERR;
	memcpy(bin, n, len_n);
	memcpy(bin + len_n, bytes, len_bytes);
	hash(alg, bin, nbytes, buff);
	srp_free(bin);
	mpz_from_bin(buff, hash_length(alg), result);
	return SRP_OK;
}

static int calculate_x(mpz_t result, SRP_HashAlgorithm alg, const unsigned char *salt,
	size_t salt_len, const char *username, const unsigned char *password,
	size_t password_len)
{
	unsigned char ucp_hash[SHA512_DIGEST_LENGTH];
	HashCTX ctx;
	hash_init(alg, &ctx);

	srp_dbg_data((char *)username, strlen(username), "Username for x: ");
	srp_dbg_data((char *)password, password_len, "Password for x: ");
	hash_update(alg, &ctx, username, strlen(username));
	hash_update(alg, &ctx, ":", 1);
	hash_update(alg, &ctx, password, password_len);

	hash_final(alg, &ctx, ucp_hash);

	return H_ns(result, alg, salt, salt_len, ucp_hash, hash_length(alg));
}

static SRP_Result update_hash_n(SRP_HashAlgorithm alg, HashCTX *ctx, const mpz_t n)
{
	size_t len = mpz_num_bytes(n);
	unsigned char *n_bytes = (unsigned char *)srp_alloc(len);
	if (!n_bytes) return SRP_ERR;
	mpz_to_bin(n, n_bytes);
	hash_update(alg, ctx, n_bytes, len);
	srp_free(n_bytes);
	return SRP_OK;
}

static SRP_Result hash_num(SRP_HashAlgorithm alg, const mpz_t n, unsigned char *dest)
{
	int nbytes = mpz_num_bytes(n);
	unsigned char *bin = (unsigned char *)srp_alloc(nbytes);
	if (!bin) return SRP_ERR;
	mpz_to_bin(n, bin);
	hash(alg, bin, nbytes, dest);
	srp_free(bin);
	return SRP_OK;
}

static SRP_Result calculate_M(SRP_HashAlgorithm alg, NGConstant *ng, unsigned char *dest,
	const char *I, const unsigned char *s_bytes, size_t s_len, const mpz_t A,
	const mpz_t B, const unsigned char *K)
{
	unsigned char H_N[SHA512_DIGEST_LENGTH];
	unsigned char H_g[SHA512_DIGEST_LENGTH];
	unsigned char H_I[SHA512_DIGEST_LENGTH];
	unsigned char H_xor[SHA512_DIGEST_LENGTH];
	HashCTX ctx;
	size_t i = 0;
	size_t hash_len = hash_length(alg);

	if (!hash_num(alg, ng->N, H_N)) return SRP_ERR;
	if (!hash_num(alg, ng->g, H_g)) return SRP_ERR;

	hash(alg, (const unsigned char *)I, strlen(I), H_I);

	for (i = 0; i < hash_len; i++)
		H_xor[i] = H_N[i] ^ H_g[i];

	hash_init(alg, &ctx);

	hash_update(alg, &ctx, H_xor, hash_len);
	hash_update(alg, &ctx, H_I, hash_len);
	hash_update(alg, &ctx, s_bytes, s_len);
	if (!update_hash_n(alg, &ctx, A)) return SRP_ERR;
	if (!update_hash_n(alg, &ctx, B)) return SRP_ERR;
	hash_update(alg, &ctx, K, hash_len);

	hash_final(alg, &ctx, dest);
	return SRP_OK;
}

static SRP_Result calculate_H_AMK(SRP_HashAlgorithm alg, unsigned char *dest,
	const mpz_t A, const unsigned char *M, const unsigned char *K)
{
	HashCTX ctx;

	hash_init(alg, &ctx);

	if (!update_hash_n(alg, &ctx, A)) return SRP_ERR;
	hash_update(alg, &ctx, M, hash_length(alg));
	hash_update(alg, &ctx, K, hash_length(alg));

	hash_final(alg, &ctx, dest);
	return SRP_OK;
}

static SRP_Result fill_buff()
{
	g_rand_idx = 0;

#ifdef WIN32
	HCRYPTPROV wctx;
#else
	FILE *fp = 0;
#endif

#ifdef WIN32

	if (!CryptAcquireContext(&wctx, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
		return SRP_ERR;
	if (!CryptGenRandom(wctx, sizeof(g_rand_buff), (BYTE *)g_rand_buff)) return SRP_ERR;
	if (!CryptReleaseContext(wctx, 0)) return SRP_ERR;

#else
	fp = fopen("/dev/urandom", "r");

	if (!fp) return SRP_ERR;

	if (fread(g_rand_buff, sizeof(g_rand_buff), 1, fp) != 1) { fclose(fp); return SRP_ERR; }
	if (fclose(fp)) return SRP_ERR;
#endif
	return SRP_OK;
}

static SRP_Result mpz_fill_random(mpz_t num)
{
	// was call: BN_rand(num, 256, -1, 0);
	if (RAND_BUFF_MAX - g_rand_idx < 32)
		if (fill_buff() != SRP_OK) return SRP_ERR;
	mpz_from_bin((const unsigned char *)(&g_rand_buff[g_rand_idx]), 32, num);
	g_rand_idx += 32;
	return SRP_OK;
}

static SRP_Result init_random()
{
	if (g_initialized) return SRP_OK;
	SRP_Result ret = fill_buff();
	g_initialized = (ret == SRP_OK);
	return ret;
}

#define srp_dbg_num(num, text) ;
/*void srp_dbg_num(mpz_t num, char * prevtext)
{
	int len_num = mpz_num_bytes(num);
	char *bytes_num = (char*) srp_alloc(len_num);
	mpz_to_bin(num, (unsigned char *) bytes_num);
	srp_dbg_data(bytes_num, len_num, prevtext);
	srp_free(bytes_num);

}*/

/***********************************************************************************************************
 *
 *  Exported Functions
 *
 ***********************************************************************************************************/

// clang-format off
SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,
	SRP_NGType ng_type, const char *username_for_verifier,
	const unsigned char *password, size_t len_password,
	unsigned char **bytes_s,  size_t *len_s,
	unsigned char **bytes_v, size_t *len_v,
	const char *n_hex, const char *g_hex )
{
	SRP_Result ret = SRP_OK;

	mpz_t v; mpz_init(v);
	mpz_t x; mpz_init(x);
	// clang-format on

	NGConstant *ng = new_ng(ng_type, n_hex, g_hex);

	if (!ng) goto error_and_exit;

	if (init_random() != SRP_OK) /* Only happens once */
		goto error_and_exit;

	if (*bytes_s == NULL) {
		size_t size_to_fill = 16;
		*len_s = size_to_fill;
		if (RAND_BUFF_MAX - g_rand_idx < size_to_fill)
			if (fill_buff() != SRP_OK) goto error_and_exit;
		*bytes_s = (unsigned char *)srp_alloc(size_to_fill);
		if (!*bytes_s) goto error_and_exit;
		memcpy(*bytes_s, &g_rand_buff[g_rand_idx], size_to_fill);
		g_rand_idx += size_to_fill;
	}

	if (!calculate_x(
			x, alg, *bytes_s, *len_s, username_for_verifier, password, len_password))
		goto error_and_exit;

	srp_dbg_num(x, "Server calculated x: ");

	mpz_powm(v, ng->g, x, ng->N);

	*len_v = mpz_num_bytes(v);

	*bytes_v = (unsigned char *)srp_alloc(*len_v);

	if (!*bytes_v) goto error_and_exit;

	mpz_to_bin(v, *bytes_v);

cleanup_and_exit:
	delete_ng(ng);
	mpz_clear(v);
	mpz_clear(x);
	return ret;
error_and_exit:
	ret = SRP_ERR;
	goto cleanup_and_exit;
}

// clang-format off

/* Out: bytes_B, len_B.
 *
 * On failure, bytes_B will be set to NULL and len_B will be set to 0
 */
struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
	SRP_NGType ng_type, const char *username,
	const unsigned char *bytes_s, size_t len_s,
	const unsigned char *bytes_v, size_t len_v,
	const unsigned char *bytes_A, size_t len_A,
	const unsigned char *bytes_b, size_t len_b,
	unsigned char **bytes_B, size_t *len_B,
	const char *n_hex, const char *g_hex )
{
	mpz_t v; mpz_init(v); mpz_from_bin(bytes_v, len_v, v);
	mpz_t A; mpz_init(A); mpz_from_bin(bytes_A, len_A, A);
	mpz_t u; mpz_init(u);
	mpz_t B; mpz_init(B);
	mpz_t S; mpz_init(S);
	mpz_t b; mpz_init(b);
	mpz_t k; mpz_init(k);
	mpz_t tmp1; mpz_init(tmp1);
	mpz_t tmp2; mpz_init(tmp2);
	mpz_t tmp3; mpz_init(tmp3);
	// clang-format on
	size_t ulen = strlen(username) + 1;
	NGConstant *ng = new_ng(ng_type, n_hex, g_hex);
	struct SRPVerifier *ver = 0;

	*len_B = 0;
	*bytes_B = 0;

	if (!ng) goto cleanup_and_exit;

	ver = (struct SRPVerifier *)srp_alloc(sizeof(struct SRPVerifier));

	if (!ver) goto cleanup_and_exit;

	if (init_random() != SRP_OK) { /* Only happens once */
		srp_free(ver);
		ver = 0;
		goto cleanup_and_exit;
	}

	ver->username = (char *)srp_alloc(ulen);
	ver->hash_alg = alg;
	ver->ng = ng;

	if (!ver->username) {
		srp_free(ver);
		ver = 0;
		goto cleanup_and_exit;
	}

	memcpy(ver->username, username, ulen);

	ver->authenticated = 0;

	/* SRP-6a safety check */
	mpz_mod(tmp1, A, ng->N);
	if (mpz_sgn(tmp1) != 0) {
		if (bytes_b) {
			mpz_from_bin(bytes_b, len_b, b);
		} else {
			if (!mpz_fill_random(b)) goto ver_cleanup_and_exit;
		}

		if (!H_nn(k, alg, ng->N, ng->N, ng->g)) goto ver_cleanup_and_exit;

		/* B = kv + g^b */
		mpz_mulm(tmp1, k, v, ng->N, tmp3);
		mpz_powm(tmp2, ng->g, b, ng->N);
		mpz_addm(B, tmp1, tmp2, ng->N, tmp3);

		if (!H_nn(u, alg, ng->N, A, B)) goto ver_cleanup_and_exit;

		srp_dbg_num(u, "Server calculated u: ");

		/* S = (A *(v^u)) ^ b */
		mpz_powm(tmp1, v, u, ng->N);
		mpz_mulm(tmp2, A, tmp1, ng->N, tmp3);
		mpz_powm(S, tmp2, b, ng->N);

		if (!hash_num(alg, S, ver->session_key)) goto ver_cleanup_and_exit;

		if (!calculate_M(
				alg, ng, ver->M, username, bytes_s, len_s, A, B, ver->session_key)) {
			goto ver_cleanup_and_exit;
		}
		if (!calculate_H_AMK(alg, ver->H_AMK, A, ver->M, ver->session_key)) {
			goto ver_cleanup_and_exit;
		}

		*len_B = mpz_num_bytes(B);
		*bytes_B = (unsigned char *)srp_alloc(*len_B);

		if (!*bytes_B) {
			*len_B = 0;
			goto ver_cleanup_and_exit;
		}

		mpz_to_bin(B, *bytes_B);

		ver->bytes_B = *bytes_B;
	} else {
		srp_free(ver);
		ver = 0;
	}

cleanup_and_exit:
	mpz_clear(v);
	mpz_clear(A);
	mpz_clear(u);
	mpz_clear(k);
	mpz_clear(B);
	mpz_clear(S);
	mpz_clear(b);
	mpz_clear(tmp1);
	mpz_clear(tmp2);
	mpz_clear(tmp3);
	return ver;
ver_cleanup_and_exit:
	srp_free(ver->username);
	srp_free(ver);
	ver = 0;
	goto cleanup_and_exit;
}

void srp_verifier_delete(struct SRPVerifier *ver)
{
	if (ver) {
		delete_ng(ver->ng);
		srp_free(ver->username);
		srp_free(ver->bytes_B);
		memset(ver, 0, sizeof(*ver));
		srp_free(ver);
	}
}

int srp_verifier_is_authenticated(struct SRPVerifier *ver)
{
	return ver->authenticated;
}

const char *srp_verifier_get_username(struct SRPVerifier *ver)
{
	return ver->username;
}

const unsigned char *srp_verifier_get_session_key(
	struct SRPVerifier *ver, size_t *key_length)
{
	if (key_length) *key_length = hash_length(ver->hash_alg);
	return ver->session_key;
}

size_t srp_verifier_get_session_key_length(struct SRPVerifier *ver)
{
	return hash_length(ver->hash_alg);
}

/* user_M must be exactly SHA512_DIGEST_LENGTH bytes in size */
void srp_verifier_verify_session(
	struct SRPVerifier *ver, const unsigned char *user_M, unsigned char **bytes_HAMK)
{
	if (memcmp(ver->M, user_M, hash_length(ver->hash_alg)) == 0) {
		ver->authenticated = 1;
		*bytes_HAMK = ver->H_AMK;
	} else
		*bytes_HAMK = NULL;
}

/*******************************************************************************/

struct SRPUser *srp_user_new(SRP_HashAlgorithm alg, SRP_NGType ng_type,
	const char *username, const char *username_for_verifier,
	const unsigned char *bytes_password, size_t len_password, const char *n_hex,
	const char *g_hex)
{
	struct SRPUser *usr = (struct SRPUser *)srp_alloc(sizeof(struct SRPUser));
	size_t ulen = strlen(username) + 1;
	size_t uvlen = strlen(username_for_verifier) + 1;

	if (!usr) goto err_exit;

	if (init_random() != SRP_OK) /* Only happens once */
		goto err_exit;

	usr->hash_alg = alg;
	usr->ng = new_ng(ng_type, n_hex, g_hex);

	mpz_init(usr->a);
	mpz_init(usr->A);
	mpz_init(usr->S);

	if (!usr->ng) goto err_exit;

	usr->username = (char *)srp_alloc(ulen);
	usr->username_verifier = (char *)srp_alloc(uvlen);
	usr->password = (unsigned char *)srp_alloc(len_password);
	usr->password_len = len_password;

	if (!usr->username || !usr->password || !usr->username_verifier) goto err_exit;

	memcpy(usr->username, username, ulen);
	memcpy(usr->username_verifier, username_for_verifier, uvlen);
	memcpy(usr->password, bytes_password, len_password);

	usr->authenticated = 0;

	usr->bytes_A = 0;

	return usr;

err_exit:
	if (usr) {
		mpz_clear(usr->a);
		mpz_clear(usr->A);
		mpz_clear(usr->S);
		delete_ng(usr->ng);
		srp_free(usr->username);
		srp_free(usr->username_verifier);
		if (usr->password) {
			memset(usr->password, 0, usr->password_len);
			srp_free(usr->password);
		}
		srp_free(usr);
	}

	return 0;
}

void srp_user_delete(struct SRPUser *usr)
{
	if (usr) {
		mpz_clear(usr->a);
		mpz_clear(usr->A);
		mpz_clear(usr->S);

		delete_ng(usr->ng);

		memset(usr->password, 0, usr->password_len);

		srp_free(usr->username);
		srp_free(usr->username_verifier);
		srp_free(usr->password);

		if (usr->bytes_A) srp_free(usr->bytes_A);

		memset(usr, 0, sizeof(*usr));
		srp_free(usr);
	}
}

int srp_user_is_authenticated(struct SRPUser *usr)
{
	return usr->authenticated;
}

const char *srp_user_get_username(struct SRPUser *usr)
{
	return usr->username;
}

const unsigned char *srp_user_get_session_key(struct SRPUser *usr, size_t *key_length)
{
	if (key_length) *key_length = hash_length(usr->hash_alg);
	return usr->session_key;
}

size_t srp_user_get_session_key_length(struct SRPUser *usr)
{
	return hash_length(usr->hash_alg);
}

// clang-format off
/* Output: username, bytes_A, len_A */
SRP_Result srp_user_start_authentication(struct SRPUser *usr, char **username,
	const unsigned char *bytes_a, size_t len_a,
	unsigned char **bytes_A, size_t *len_A)
{
	// clang-format on
	if (bytes_a) {
		mpz_from_bin(bytes_a, len_a, usr->a);
	} else {
		if (!mpz_fill_random(usr->a)) goto error_and_exit;
	}

	mpz_powm(usr->A, usr->ng->g, usr->a, usr->ng->N);

	*len_A = mpz_num_bytes(usr->A);
	*bytes_A = (unsigned char *)srp_alloc(*len_A);

	if (!*bytes_A) goto error_and_exit;

	mpz_to_bin(usr->A, *bytes_A);

	usr->bytes_A = *bytes_A;
	if (username) *username = usr->username;

	return SRP_OK;

error_and_exit:
	*len_A = 0;
	*bytes_A = 0;
	*username = 0;
	return SRP_ERR;
}

// clang-format off
/* Output: bytes_M. Buffer length is SHA512_DIGEST_LENGTH */
void  srp_user_process_challenge(struct SRPUser *usr,
	const unsigned char *bytes_s, size_t len_s,
	const unsigned char *bytes_B, size_t len_B,
	unsigned char **bytes_M, size_t *len_M)
{
	mpz_t B; mpz_init(B); mpz_from_bin(bytes_B, len_B, B);
	mpz_t u; mpz_init(u);
	mpz_t x; mpz_init(x);
	mpz_t k; mpz_init(k);
	mpz_t v; mpz_init(v);
	mpz_t tmp1; mpz_init(tmp1);
	mpz_t tmp2; mpz_init(tmp2);
	mpz_t tmp3; mpz_init(tmp3);
	mpz_t tmp4; mpz_init(tmp4);
	// clang-format on

	*len_M = 0;
	*bytes_M = 0;

	if (!H_nn(u, usr->hash_alg, usr->ng->N, usr->A, B)) goto cleanup_and_exit;

	srp_dbg_num(u, "Client calculated u: ");

	if (!calculate_x(x, usr->hash_alg, bytes_s, len_s, usr->username_verifier,
			usr->password, usr->password_len))
		goto cleanup_and_exit;

	srp_dbg_num(x, "Client calculated x: ");

	if (!H_nn(k, usr->hash_alg, usr->ng->N, usr->ng->N, usr->ng->g))
		goto cleanup_and_exit;

	/* SRP-6a safety check */
	if (mpz_sgn(B) != 0 && mpz_sgn(u) != 0) {
		mpz_powm(v, usr->ng->g, x, usr->ng->N);

		srp_dbg_num(v, "Client calculated v: ");

		// clang-format off
		/* S = (B - k*(g^x)) ^ (a + ux) */
		mpz_mul(tmp1, u, x);
		mpz_add(tmp2, usr->a, tmp1);               /* tmp2 = (a + ux)      */
		mpz_powm(tmp1, usr->ng->g, x, usr->ng->N); /* tmp1 = g^x           */
		mpz_mulm(tmp3, k, tmp1, usr->ng->N, tmp4); /* tmp3 = k*(g^x)       */
		mpz_subm(tmp1, B, tmp3, usr->ng->N, tmp4); /* tmp1 = (B - K*(g^x)) */
		mpz_powm(usr->S, tmp1, tmp2, usr->ng->N);
		// clang-format on

		if (!hash_num(usr->hash_alg, usr->S, usr->session_key)) goto cleanup_and_exit;

		if (!calculate_M(usr->hash_alg, usr->ng, usr->M, usr->username, bytes_s, len_s,
				usr->A, B, usr->session_key))
			goto cleanup_and_exit;
		if (!calculate_H_AMK(usr->hash_alg, usr->H_AMK, usr->A, usr->M, usr->session_key))
			goto cleanup_and_exit;

		*bytes_M = usr->M;
		if (len_M) *len_M = hash_length(usr->hash_alg);
	} else {
		*bytes_M = NULL;
		if (len_M) *len_M = 0;
	}

cleanup_and_exit:
	mpz_clear(B);
	mpz_clear(u);
	mpz_clear(x);
	mpz_clear(k);
	mpz_clear(v);
	mpz_clear(tmp1);
	mpz_clear(tmp2);
	mpz_clear(tmp3);
	mpz_clear(tmp4);
}

void srp_user_verify_session(struct SRPUser *usr, const unsigned char *bytes_HAMK)
{
	if (memcmp(usr->H_AMK, bytes_HAMK, hash_length(usr->hash_alg)) == 0)
		usr->authenticated = 1;
}