605 changes: 279 additions & 326 deletions src/util/srp.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,12 +26,14 @@
*
*/

// clang-format off
#ifdef WIN32
#include <windows.h>
#include <wincrypt.h>
#else
#include <time.h>
#endif
// clang-format on

#include <stdlib.h>
#include <string.h>
Expand Down Expand Up @@ -69,116 +71,116 @@ static int g_initialized = 0;
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;
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 *)) {
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
{
typedef struct {
mpz_t N;
mpz_t g;
} NGConstant;

struct NGHex
{
const char* n_hex;
const char* g_hex;
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 */
"EEAF0AB9ADB38DD69C33F80AFA8FC5E86072618775FF3C0B9EA2314C9C256576D674DF7496"
"EA81D3383B4813D692C6E0E0D5D8E250B98BE48E495C1D6089DAD15DC7D7B46154D6B6CE8E"
"F4AD69B15D4982559B297BCF1885C529F566660E57EC68EDBC3C05726CC02FD4CBF4976EAA"
"9AFD5138FE8376435B9FC61D2FC0EB06E3",
"2"
},
{ /* 2048 */
"AC6BDB41324A9A9BF166DE5E1389582FAF72B6651987EE07FC3192943DB56050A37329CBB4"
"A099ED8193E0757767A13DD52312AB4B03310DCD7F48A9DA04FD50E8083969EDB767B0CF60"
"95179A163AB3661A05FBD5FAAAE82918A9962F0B93B855F97993EC975EEAA80D740ADBF4FF"
"747359D041D5C33EA71D281E446B14773BCA97B43A23FB801676BD207A436C6481F1D2B907"
"8717461A5B9D32E688F87748544523B524B0D57D5EA77A2775D2ECFA032CFBDBF52FB37861"
"60279004E57AE6AF874E7303CE53299CCC041C7BC308D82A5698F3A8D0C38271AE35F8E9DB"
"FBB694B5C803D89F7AE435DE236D525F54759B65E372FCD68EF20FA7111F9E4AFF73",
"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 */
{/* 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) {
Expand All @@ -188,18 +190,18 @@ static void delete_ng(NGConstant *ng)
}
}

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

if (!ng) return 0;

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ShadowNinja Apr 28, 2016

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0 -> NULL

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

if (!ng)
return 0;

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

int rv = 0;
Expand All @@ -214,17 +216,13 @@ static NGConstant *new_ng( SRP_NGType ng_type, const char *n_hex, const char *g_
return ng;
}


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


struct SRPVerifier
{
struct SRPVerifier {
SRP_HashAlgorithm hash_alg;
NGConstant *ng;

Expand All @@ -237,9 +235,7 @@ struct SRPVerifier
unsigned char session_key[SHA512_DIGEST_LENGTH];
};


struct SRPUser
{
struct SRPUser {
SRP_HashAlgorithm hash_alg;
NGConstant *ng;

Expand All @@ -260,19 +256,23 @@ struct SRPUser
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);*/
/*
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);*/
/*
case SRP_SHA384: return SHA384_Init(&c->sha512);
case SRP_SHA512: return SHA512_Init(&c->sha512);
*/
default: return -1;
};
}
Expand All @@ -282,12 +282,16 @@ static int hash_update( SRP_HashAlgorithm alg, HashCTX *c, const void *data, siz
#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);*/
/*
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 );*/
/*
case SRP_SHA384: return SHA384_Update(&c->sha512, data, len);
case SRP_SHA512: return SHA512_Update(&c->sha512, data, len);
*/
default: return -1;
};
}
Expand All @@ -297,12 +301,16 @@ static int hash_final( SRP_HashAlgorithm alg, HashCTX *c, unsigned char *md )
#ifdef CSRP_USE_SHA1
case SRP_SHA1: return SHA1_Final(md, &c->sha);
#endif
/*case SRP_SHA224: return SHA224_Final(md, &c->sha256);*/
/*
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);*/
/*
case SRP_SHA384: return SHA384_Final(md, &c->sha512);
case SRP_SHA512: return SHA512_Final(md, &c->sha512);
*/
default: return -1;
};
}
Expand All @@ -312,12 +320,16 @@ static unsigned char *hash(SRP_HashAlgorithm alg, const unsigned char *d, size_t
#ifdef CSRP_USE_SHA1
case SRP_SHA1: return SHA1(d, n, md);
#endif
/*case SRP_SHA224: return SHA224( d, n, md );*/
/*
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 );*/
/*
case SRP_SHA384: return SHA384( d, n, md );
case SRP_SHA512: return SHA512( d, n, md );
*/
default: return 0;
};
}
Expand All @@ -327,19 +339,24 @@ static size_t hash_length(SRP_HashAlgorithm alg)
#ifdef CSRP_USE_SHA1
case SRP_SHA1: return SHA_DIGEST_LENGTH;
#endif
/*case SRP_SHA224: return SHA224_DIGEST_LENGTH;*/
/*
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;*/
/*
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;
return (mpz_sizeinbase(op, 2) + 7) / 8;
}

inline static void mpz_to_bin(const mpz_t op, unsigned char *to)
Expand All @@ -353,72 +370,77 @@ inline static void mpz_from_bin(const unsigned char *s, size_t len, mpz_t ret)
}

// 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)
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 )
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)
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 int H_nn(mpz_t result, SRP_HashAlgorithm alg, const mpz_t N, const mpz_t n1, const mpz_t n2)
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 0;
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 0;
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 );
hash(alg, bin, nbytes, buff);
srp_free(bin);
mpz_from_bin(buff, hash_length(alg), result);
return 1;
return SRP_OK;
}

static int H_ns(mpz_t result, SRP_HashAlgorithm alg, const unsigned char *n, size_t len_n, const unsigned char *bytes, size_t len_bytes)
static SRP_Result H_ns(mpz_t result, SRP_HashAlgorithm alg, const unsigned char *n,
size_t len_n, const unsigned char *bytes, size_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 0;
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 1;
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)
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: ");
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);
Expand All @@ -428,31 +450,31 @@ static int calculate_x(mpz_t result, SRP_HashAlgorithm alg, const unsigned char
return H_ns(result, alg, salt, salt_len, ucp_hash, hash_length(alg));
}

static void update_hash_n(SRP_HashAlgorithm alg, HashCTX *ctx, const mpz_t n)
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;
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 void hash_num( SRP_HashAlgorithm alg, const mpz_t n, unsigned char *dest )
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;
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 void 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)
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];
Expand All @@ -462,68 +484,42 @@ static void calculate_M(SRP_HashAlgorithm alg, NGConstant *ng, unsigned char *de
size_t i = 0;
size_t hash_len = hash_length(alg);

hash_num(alg, ng->N, H_N);
hash_num(alg, ng->g, H_g);
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++ )
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);
update_hash_n(alg, &ctx, A);
update_hash_n(alg, &ctx, B);
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 void calculate_H_AMK(SRP_HashAlgorithm alg, unsigned char *dest, const mpz_t A, const unsigned char *M, const unsigned char *K)
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);

update_hash_n(alg, &ctx, A);
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;
}

#ifndef WIN32

struct srp_pcgrandom {
unsigned long long int m_state;
unsigned long long int m_inc;
}; typedef struct srp_pcgrandom srp_pcgrandom;

static unsigned long int srp_pcgrandom_next(srp_pcgrandom *r)
{
unsigned long long int oldstate = r->m_state;
r->m_state = oldstate * 6364136223846793005ULL + r->m_inc;

unsigned long int xorshifted = ((oldstate >> 18u) ^ oldstate) >> 27u;
unsigned long int rot = oldstate >> 59u;
return (xorshifted >> rot) | (xorshifted << ((-rot) & 31));
}

static void srp_pcgrandom_seed(srp_pcgrandom *r, unsigned long long int state,
unsigned long long int seq)
{
r->m_state = 0U;
r->m_inc = (seq << 1u) | 1u;
srp_pcgrandom_next(r);
r->m_state += state;
srp_pcgrandom_next(r);
}
#endif

static SRP_Result fill_buff()
{
g_rand_idx = 0;
Expand All @@ -536,29 +532,18 @@ static SRP_Result fill_buff()

#ifdef WIN32

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

return SRP_OK;
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) {
fread(g_rand_buff, sizeof(g_rand_buff), 1, fp);
fclose(fp);
} else {
srp_pcgrandom *r = (srp_pcgrandom *) srp_alloc(sizeof(srp_pcgrandom));
if (!r)
return SRP_ERR;
srp_pcgrandom_seed(r, time(NULL) ^ clock(), 0xda3e39cb94b95bdbULL);
size_t i = 0;
for (i = 0; i < RAND_BUFF_MAX; i++) {
g_rand_buff[i] = srp_pcgrandom_next(r);
}
srp_free(r);
}
if (!fp) return SRP_ERR;

if (fread(g_rand_buff, sizeof(g_rand_buff), 1, fp) != 1) return SRP_ERR;
if (fclose(fp)) return SRP_ERR;
#endif
return SRP_OK;
}
Expand All @@ -567,17 +552,15 @@ 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);
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;
if (g_initialized) return SRP_OK;
SRP_Result ret = fill_buff();
g_initialized = (ret == SRP_OK);
return ret;
Expand All @@ -600,6 +583,7 @@ static SRP_Result init_random()
*
***********************************************************************************************************/

// 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,
Expand All @@ -611,10 +595,11 @@ SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,

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 (!ng) goto error_and_exit;

if (init_random() != SRP_OK) /* Only happens once */
goto error_and_exit;
Expand All @@ -623,18 +608,15 @@ SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,
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;
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))
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: ");
Expand All @@ -643,15 +625,14 @@ SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,

*len_v = mpz_num_bytes(v);

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

if (!bytes_v)
goto error_and_exit;
if (!*bytes_v) goto error_and_exit;

mpz_to_bin(v, *bytes_v);

cleanup_and_exit:
delete_ng( ng );
delete_ng(ng);
mpz_clear(v);
mpz_clear(x);
return ret;
Expand All @@ -660,7 +641,7 @@ SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,
goto cleanup_and_exit;
}


// clang-format off

/* Out: bytes_B, len_B.
*
Expand All @@ -685,28 +666,27 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
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;
if (!ng) goto cleanup_and_exit;

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

if (!ver)
goto cleanup_and_exit;
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->username = (char *)srp_alloc(ulen);
ver->hash_alg = alg;
ver->ng = ng;

Expand All @@ -716,7 +696,7 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
goto cleanup_and_exit;
}

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

ver->authenticated = 0;

Expand All @@ -726,29 +706,17 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
if (bytes_b) {
mpz_from_bin(bytes_b, len_b, b);
} else {
if (mpz_fill_random(b) != SRP_OK) {
srp_free(ver);
ver = 0;
goto cleanup_and_exit;
}
if (!mpz_fill_random(b)) goto ver_cleanup_and_exit;
}

if (!H_nn(k, alg, ng->N, ng->N, ng->g)) {
srp_free(ver);
ver = 0;
goto 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)) {
srp_free(ver);
ver = 0;
goto cleanup_and_exit;
}
if (!H_nn(u, alg, ng->N, A, B)) goto ver_cleanup_and_exit;

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

Expand All @@ -757,20 +725,22 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
mpz_mulm(tmp2, A, tmp1, ng->N, tmp3);
mpz_powm(S, tmp2, b, ng->N);

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

calculate_M(alg, ng, ver->M, username, bytes_s, len_s, A, B, ver->session_key);
calculate_H_AMK(alg, ver->H_AMK, A, ver->M, ver->session_key);
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);
*bytes_B = (unsigned char *)srp_alloc(*len_B);

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

mpz_to_bin(B, *bytes_B);
Expand All @@ -793,11 +763,13 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
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) {
Expand All @@ -809,36 +781,31 @@ void srp_verifier_delete(struct SRPVerifier *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)
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);
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)
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;
Expand All @@ -851,15 +818,14 @@ void srp_verifier_verify_session(struct SRPVerifier *ver, const unsigned char *u

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)
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;
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 (!usr) goto err_exit;

if (init_random() != SRP_OK) /* Only happens once */
goto err_exit;
Expand All @@ -871,16 +837,14 @@ struct SRPUser *srp_user_new(SRP_HashAlgorithm alg, SRP_NGType ng_type,
mpz_init(usr->A);
mpz_init(usr->S);

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

memcpy(usr->username, username, ulen);
memcpy(usr->username_verifier, username_for_verifier, uvlen);
Expand All @@ -897,8 +861,7 @@ struct SRPUser *srp_user_new(SRP_HashAlgorithm alg, SRP_NGType ng_type,
mpz_clear(usr->a);
mpz_clear(usr->A);
mpz_clear(usr->S);
if (usr->ng)
delete_ng(usr->ng);
if (usr->ng) delete_ng(usr->ng);
srp_free(usr->username);
srp_free(usr->username_verifier);
if (usr->password) {
Expand All @@ -911,11 +874,9 @@ struct SRPUser *srp_user_new(SRP_HashAlgorithm alg, SRP_NGType ng_type,
return 0;
}



void srp_user_delete(struct SRPUser *usr)
{
if(usr) {
if (usr) {
mpz_clear(usr->a);
mpz_clear(usr->A);
mpz_clear(usr->S);
Expand All @@ -928,67 +889,58 @@ void srp_user_delete(struct SRPUser *usr)
srp_free(usr->username_verifier);
srp_free(usr->password);

if (usr->bytes_A)
srp_free(usr->bytes_A);
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)
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);
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) != SRP_OK)
goto error_and_exit;
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);
*bytes_A = (unsigned char *)srp_alloc(*len_A);

if (!*bytes_A)
goto error_and_exit;
if (!*bytes_A) goto error_and_exit;

mpz_to_bin(usr->A, *bytes_A);

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

return SRP_OK;

Expand All @@ -999,7 +951,7 @@ SRP_Result srp_user_start_authentication(struct SRPUser *usr, char **username,
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,
Expand All @@ -1015,17 +967,17 @@ void srp_user_process_challenge(struct SRPUser *usr,
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;
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))
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: ");
Expand All @@ -1034,35 +986,37 @@ void srp_user_process_challenge(struct SRPUser *usr,
goto cleanup_and_exit;

/* SRP-6a safety check */
if ( mpz_sgn(B) != 0 && mpz_sgn(u) != 0 ) {
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

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

calculate_M( usr->hash_alg, usr->ng, usr->M, usr->username, bytes_s, len_s, usr->A,B, usr->session_key );
calculate_H_AMK( usr->hash_alg, usr->H_AMK, usr->A, usr->M, usr->session_key );
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 );
if (len_M) *len_M = hash_length(usr->hash_alg);
} else {
*bytes_M = NULL;
if (len_M)
*len_M = 0;
if (len_M) *len_M = 0;
}

cleanup_and_exit:

mpz_clear(B);
mpz_clear(u);
mpz_clear(x);
Expand All @@ -1074,7 +1028,6 @@ void srp_user_process_challenge(struct SRPUser *usr,
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)
Expand Down
70 changes: 35 additions & 35 deletions src/util/srp.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -56,34 +56,32 @@
#ifndef SRP_H
#define SRP_H


struct SRPVerifier;
struct SRPUser;

typedef enum
{
typedef enum {
SRP_NG_1024,
SRP_NG_2048,
SRP_NG_4096,
SRP_NG_8192,
SRP_NG_CUSTOM
} SRP_NGType;

typedef enum
{
typedef enum {
/*SRP_SHA1,*/
/*SRP_SHA224,*/
SRP_SHA256,
/*SRP_SHA384,
SRP_SHA512*/
} SRP_HashAlgorithm;

typedef enum
{
SRP_OK,
typedef enum {
SRP_ERR,
SRP_OK,
} SRP_Result;

// clang-format off

/* Sets the memory functions used by srp.
* Note: this doesn't set the memory functions used by gmp,
* but it is supported to have different functions for srp and gmp.
Expand All @@ -101,17 +99,18 @@ void srp_set_memory_functions(
* The n_hex and g_hex parameters should be 0 unless SRP_NG_CUSTOM is used for ng_type.
* If provided, they must contain ASCII text of the hexidecimal notation.
*
* If bytes_s == NULL, it is filled with random data. The caller is responsible for freeing.
* If bytes_s == NULL, it is filled with random data.
* The caller is responsible for freeing.
*
* Returns SRP_OK on success, and SRP_ERR on error.
* bytes_s might be in this case invalid, don't free it.
*/
SRP_Result srp_create_salted_verification_key( SRP_HashAlgorithm alg,
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 );
const char *n_hex, const char *g_hex);

/* Out: bytes_B, len_B.
*
Expand All @@ -132,63 +131,64 @@ struct SRPVerifier* srp_verifier_new(SRP_HashAlgorithm alg, SRP_NGType ng_type,
unsigned char** bytes_B, size_t *len_B,
const char* n_hex, const char* g_hex);

// clang-format on

void srp_verifier_delete( struct SRPVerifier* ver );
void srp_verifier_delete(struct SRPVerifier *ver);

// srp_verifier_verify_session must have been called before
int srp_verifier_is_authenticated( struct SRPVerifier* ver );

int srp_verifier_is_authenticated(struct SRPVerifier *ver);

const char * srp_verifier_get_username( struct SRPVerifier* ver );
const char *srp_verifier_get_username(struct SRPVerifier *ver);

/* key_length may be null */
const unsigned char* srp_verifier_get_session_key( struct SRPVerifier* ver,
size_t *key_length );


size_t srp_verifier_get_session_key_length(struct SRPVerifier* ver);
const unsigned char *srp_verifier_get_session_key(
struct SRPVerifier *ver, size_t *key_length);

size_t srp_verifier_get_session_key_length(struct SRPVerifier *ver);

/* Verifies session, on success, it writes bytes_HAMK.
* user_M must be exactly srp_verifier_get_session_key_length() bytes in size
*/
void srp_verifier_verify_session( struct SRPVerifier* ver,
const unsigned char* user_M, unsigned char** bytes_HAMK );
void srp_verifier_verify_session(
struct SRPVerifier *ver, const unsigned char *user_M, unsigned char **bytes_HAMK);

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

/* The n_hex and g_hex parameters should be 0 unless SRP_NG_CUSTOM is used for ng_type */
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);
const unsigned char *bytes_password, size_t len_password, const char *n_hex,
const char *g_hex);

void srp_user_delete(struct SRPUser * usr);
void srp_user_delete(struct SRPUser *usr);

int srp_user_is_authenticated(struct SRPUser * usr);
int srp_user_is_authenticated(struct SRPUser *usr);


const char* srp_user_get_username(struct SRPUser * usr);
const char *srp_user_get_username(struct SRPUser *usr);

/* key_length may be null */
const unsigned char* srp_user_get_session_key(struct SRPUser* usr, size_t* key_length);
const unsigned char *srp_user_get_session_key(struct SRPUser *usr, size_t *key_length);

size_t srp_user_get_session_key_length(struct SRPUser *usr);

size_t srp_user_get_session_key_length(struct SRPUser* usr);
// clang-format off

/* Output: username, bytes_A, len_A. If you don't want it get written, set username to NULL.
/* Output: username, bytes_A, len_A.
* If you don't want it get written, set username to NULL.
* If bytes_a == NULL, random data is used for 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);
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);

/* Output: bytes_M, len_M (len_M may be null and will always be
* srp_user_get_session_key_length() bytes in size) */
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);
// clang-format on

/* bytes_HAMK must be exactly srp_user_get_session_key_length() bytes in size */
void srp_user_verify_session(struct SRPUser* usr, const unsigned char* bytes_HAMK);
void srp_user_verify_session(struct SRPUser *usr, const unsigned char *bytes_HAMK);

#endif /* Include Guard */