#include "d0_bignum.h"
#include "sha2.h"
+// old "positive" protocol, uses one extra mod_inv in verify stages
+// #define D0_BLIND_ID_POSITIVE_PROTOCOL
+
// our SHA is SHA-256
#define SHA_DIGESTSIZE 32
const char *sha(const unsigned char *in, size_t len)
{
- static char h[32];
+ static __thread char h[32];
d0_blind_id_util_sha256(h, (const char *) in, len);
return h;
}
size_t msglen; // message length
};
+//#define CHECKDEBUG
+#ifdef CHECKDEBUG
+#define CHECK(x) do { if(!(x)) { fprintf(stderr, "CHECK FAILED (%s:%d): %s\n", __FILE__, __LINE__, #x); goto fail; } } while(0)
+#define CHECK_ASSIGN(var, value) do { d0_bignum_t *val; val = value; if(!val) { fprintf(stderr, "CHECK FAILED (%s:%d): %s\n", __FILE__, __LINE__, #value); goto fail; } var = val; } while(0)
+#else
#define CHECK(x) do { if(!(x)) goto fail; } while(0)
#define CHECK_ASSIGN(var, value) do { d0_bignum_t *val; val = value; if(!val) goto fail; var = val; } while(0)
-#define MPCHECK(x) do { if(!failed) if(!(x)) failed = 1; } while(0)
-#define MPCHECK_ASSIGN(var, value) do { if(!failed) { d0_bignum_t *val; val = value; if(val) var = val; else failed = 1; } } while(0)
+#endif
#define USING(x) if(!(ctx->x)) return 0
#define REPLACING(x)
-static d0_bignum_t *zero, *one, *four, *temp0, *temp1, *temp2, *temp3, *temp4;
+// safe to use
+static d0_bignum_t *zero, *one, *four;
+
+static d0_bignum_t *temp0, *temp1, *temp2, *temp3, *temp4;
+static void *tempmutex = NULL; // hold this mutex when using temp0 to temp4
+#define USINGTEMPS() int locked = 0
+#define LOCKTEMPS() do { if(!locked) d0_lockmutex(tempmutex); locked = 1; } while(0)
+#define UNLOCKTEMPS() do { if(locked) d0_unlockmutex(tempmutex); locked = 0; } while(0);
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_INITIALIZE(void)
{
+ USINGTEMPS();
+ tempmutex = d0_createmutex();
+ LOCKTEMPS();
CHECK(d0_bignum_INITIALIZE());
CHECK_ASSIGN(zero, d0_bignum_int(zero, 0));
CHECK_ASSIGN(one, d0_bignum_int(one, 1));
CHECK_ASSIGN(temp2, d0_bignum_int(temp2, 0));
CHECK_ASSIGN(temp3, d0_bignum_int(temp3, 0));
CHECK_ASSIGN(temp4, d0_bignum_int(temp4, 0));
+ UNLOCKTEMPS();
return 1;
fail:
+ UNLOCKTEMPS();
return 0;
}
void d0_blind_id_SHUTDOWN(void)
{
+ USINGTEMPS();
+ LOCKTEMPS();
d0_bignum_free(zero);
d0_bignum_free(one);
d0_bignum_free(four);
d0_bignum_free(temp3);
d0_bignum_free(temp4);
d0_bignum_SHUTDOWN();
+ UNLOCKTEMPS();
+ d0_destroymutex(tempmutex);
+ tempmutex = NULL;
}
// (G-1)/2
-d0_bignum_t *d0_dl_get_order(d0_bignum_t *o, const d0_bignum_t *G)
+static d0_bignum_t *d0_dl_get_order(d0_bignum_t *o, const d0_bignum_t *G)
{
CHECK_ASSIGN(o, d0_bignum_sub(o, G, one));
CHECK(d0_bignum_shl(o, o, -1)); // order o = (G-1)/2
return NULL;
}
-D0_BOOL d0_dl_generate_key(size_t size, d0_bignum_t *G)
+static D0_BOOL d0_dl_generate_key(size_t size, d0_bignum_t *G)
{
// using: temp0
if(size < 16)
return 0;
}
-D0_BOOL d0_rsa_generate_key(size_t size, const d0_bignum_t *challenge, d0_bignum_t *d, d0_bignum_t *n)
+static D0_BOOL d0_rsa_generate_key(size_t size, const d0_bignum_t *challenge, d0_bignum_t *d, d0_bignum_t *n)
{
// uses temp0 to temp4
int fail = 0;
if(!d0_bignum_cmp(temp4, one))
break;
if(++gcdfail == 3)
- return 0;
+ goto fail;
++gcdfail;
}
gcdfail = 0;
if(!d0_bignum_cmp(temp1, temp0))
{
if(++fail == 3)
- return 0;
+ goto fail;
}
fail = 0;
if(d0_bignum_isprime(temp1, 10) == 0)
if(!d0_bignum_cmp(temp4, one))
break;
if(++gcdfail == 3)
- return 0;
+ goto fail;
++gcdfail;
}
return 0;
}
-D0_BOOL d0_rsa_generate_key_fastreject(size_t size, d0_fastreject_function reject, d0_blind_id_t *ctx, void *pass)
+static D0_BOOL d0_rsa_generate_key_fastreject(size_t size, d0_fastreject_function reject, d0_blind_id_t *ctx, void *pass)
{
// uses temp0 to temp4
int fail = 0;
D0_WARN_UNUSED_RESULT D0_BOOL d0_longhash_bignum(const d0_bignum_t *in, unsigned char *outbuf, size_t outbuflen)
{
- static unsigned char convbuf[1024];
+ static __thread unsigned char convbuf[1024];
size_t sz;
CHECK(d0_bignum_export_unsigned(in, convbuf, sizeof(convbuf)) >= 0);
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_generate_private_key_fastreject(d0_blind_id_t *ctx, int k, d0_fastreject_function reject, void *pass)
{
+ USINGTEMPS();
REPLACING(rsa_e); REPLACING(rsa_d); REPLACING(rsa_n);
CHECK_ASSIGN(ctx->rsa_e, d0_bignum_int(ctx->rsa_e, 65537));
CHECK_ASSIGN(ctx->rsa_d, d0_bignum_zero(ctx->rsa_d));
CHECK_ASSIGN(ctx->rsa_n, d0_bignum_zero(ctx->rsa_n));
+ LOCKTEMPS();
if(reject)
CHECK(d0_rsa_generate_key_fastreject(k+1, reject, ctx, pass)); // must fit G for sure
else
CHECK(d0_rsa_generate_key(k+1, ctx->rsa_e, ctx->rsa_d, ctx->rsa_n)); // must fit G for sure
+ UNLOCKTEMPS();
return 1;
fail:
+ UNLOCKTEMPS();
return 0;
}
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_fingerprint64_public_key(const d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
d0_iobuf_t *out = NULL;
- static unsigned char convbuf[2048];
+ static __thread unsigned char convbuf[2048];
d0_iobuf_t *conv = NULL;
size_t sz, n;
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_generate_private_id_modulus(d0_blind_id_t *ctx)
{
+ USINGTEMPS();
USING(rsa_n);
REPLACING(schnorr_G);
CHECK_ASSIGN(ctx->schnorr_G, d0_bignum_zero(ctx->schnorr_G));
+ LOCKTEMPS();
CHECK(d0_dl_generate_key(d0_bignum_size(ctx->rsa_n)-1, ctx->schnorr_G));
+ UNLOCKTEMPS();
return 1;
fail:
+ UNLOCKTEMPS();
return 0;
}
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_generate_private_id_start(d0_blind_id_t *ctx)
{
- // temps: temp0 = order
+ USINGTEMPS(); // temps: temp0 = order
USING(schnorr_G);
REPLACING(schnorr_s); REPLACING(schnorr_g_to_s);
+ LOCKTEMPS();
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
CHECK_ASSIGN(ctx->schnorr_s, d0_bignum_rand_range(ctx->schnorr_s, zero, temp0));
CHECK_ASSIGN(ctx->schnorr_g_to_s, d0_bignum_mod_pow(ctx->schnorr_g_to_s, four, ctx->schnorr_s, ctx->schnorr_G));
CHECK_ASSIGN(ctx->schnorr_H_g_to_s_signature, d0_bignum_zero(ctx->schnorr_H_g_to_s_signature));
+ UNLOCKTEMPS();
return 1;
fail:
+ UNLOCKTEMPS();
return 0;
}
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_generate_private_id_request(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
d0_iobuf_t *out = NULL;
- static unsigned char shabuf[2048];
+ static __thread unsigned char shabuf[2048];
size_t sz;
- // temps: temp0 rsa_blind_signature_camouflage^challenge, temp1 (4^s)*rsa_blind_signature_camouflage^challenge
+ USINGTEMPS(); // temps: temp0 rsa_blind_signature_camouflage^challenge, temp1 (4^s)*rsa_blind_signature_camouflage^challenge
USING(rsa_n); USING(rsa_e); USING(schnorr_g_to_s);
REPLACING(rsa_blind_signature_camouflage);
CHECK(d0_bignum_mod_pow(temp0, ctx->rsa_blind_signature_camouflage, ctx->rsa_e, ctx->rsa_n));
// we will actually sign HA(4^s) to prevent a malleability attack!
+ LOCKTEMPS();
CHECK(d0_bignum_mov(temp2, ctx->schnorr_g_to_s));
sz = (d0_bignum_size(ctx->rsa_n) + 7) / 8; // this is too long, so we have to take the value % rsa_n when "decrypting"
if(sz > sizeof(shabuf))
// hash complete
CHECK(d0_bignum_mod_mul(temp1, temp2, temp0, ctx->rsa_n));
CHECK(d0_iobuf_write_bignum(out, temp1));
+ UNLOCKTEMPS();
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(out, outbuflen);
return 0;
}
d0_iobuf_t *in = NULL;
d0_iobuf_t *out = NULL;
- // temps: temp0 input, temp1 temp0^d
+ USINGTEMPS(); // temps: temp0 input, temp1 temp0^d
USING(rsa_d); USING(rsa_n);
in = d0_iobuf_open_read(inbuf, inbuflen);
out = d0_iobuf_open_write(outbuf, *outbuflen);
+ LOCKTEMPS();
CHECK(d0_iobuf_read_bignum(in, temp0));
CHECK(d0_bignum_mod_pow(temp1, temp0, ctx->rsa_d, ctx->rsa_n));
CHECK(d0_iobuf_write_bignum(out, temp1));
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
d0_iobuf_close(out, outbuflen);
return 0;
{
d0_iobuf_t *in = NULL;
- // temps: temp0 input, temp1 rsa_blind_signature_camouflage^-1
+ USINGTEMPS(); // temps: temp0 input, temp1 rsa_blind_signature_camouflage^-1
USING(rsa_blind_signature_camouflage); USING(rsa_n);
REPLACING(schnorr_H_g_to_s_signature);
in = d0_iobuf_open_read(inbuf, inbuflen);
+ LOCKTEMPS();
+
CHECK(d0_iobuf_read_bignum(in, temp0));
CHECK(d0_bignum_mod_inv(temp1, ctx->rsa_blind_signature_camouflage, ctx->rsa_n));
CHECK_ASSIGN(ctx->schnorr_H_g_to_s_signature, d0_bignum_mod_mul(ctx->schnorr_H_g_to_s_signature, temp0, temp1, ctx->rsa_n));
+ UNLOCKTEMPS();
return d0_iobuf_close(in, NULL);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
return 0;
}
// 1. get random r, send HASH(4^r)
{
d0_iobuf_t *out = NULL;
- static unsigned char convbuf[1024];
+ static __thread unsigned char convbuf[1024];
d0_iobuf_t *conv = NULL;
size_t sz = 0;
D0_BOOL failed = 0;
- // temps: temp0 order, temp0 4^r
+ USINGTEMPS(); // temps: temp0 order, temp0 4^r
if(is_first)
{
USING(schnorr_g_to_s); USING(schnorr_H_g_to_s_signature);
// start schnorr ID scheme
// generate random number r; x = g^r; send hash of x, remember r, forget x
+ LOCKTEMPS();
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
+#ifdef RNG_XKCD
+ CHECK_ASSIGN(ctx->r, d0_bignum_int(ctx->r, 4)); // decided by fair dice roll
+#else
CHECK_ASSIGN(ctx->r, d0_bignum_rand_range(ctx->r, zero, temp0));
- //CHECK(d0_bignum_mod_pow(temp0, four, ctx->r, ctx->schnorr_G));
+#endif
// initialize Signed Diffie Hellmann
// we already have the group order in temp1
+#ifdef RNG_XKCD
+ CHECK_ASSIGN(ctx->t, d0_bignum_int(ctx->t, 4)); // decided by fair dice roll
+#else
CHECK_ASSIGN(ctx->t, d0_bignum_rand_range(ctx->t, zero, temp0));
+#endif
// can we SOMEHOW do this with just one mod_pow?
CHECK(d0_bignum_mod_pow(temp0, four, ctx->r, ctx->schnorr_G));
CHECK(d0_iobuf_write_bignum(conv, ctx->g_to_t));
CHECK(d0_iobuf_write_packet(conv, msg, msglen));
CHECK(d0_iobuf_write_bignum(conv, temp0));
+ UNLOCKTEMPS();
CHECK(d0_iobuf_write_bignum(conv, ctx->g_to_t));
d0_iobuf_close(conv, &sz);
conv = NULL;
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(out, outbuflen);
return 0;
}
{
d0_iobuf_t *in = NULL;
d0_iobuf_t *out = NULL;
- static unsigned char shabuf[2048];
+ static __thread unsigned char shabuf[2048];
size_t sz;
- // temps: temp0 order, temp0 signature check
+ USINGTEMPS(); // temps: temp0 order, temp0 signature check
if(is_first)
{
REPLACING(schnorr_g_to_s); REPLACING(schnorr_H_g_to_s_signature);
CHECK(d0_bignum_cmp(ctx->schnorr_H_g_to_s_signature, ctx->rsa_n) < 0);
// check signature of key (t = k^d, so, t^challenge = k)
+ LOCKTEMPS();
CHECK(d0_bignum_mod_pow(temp0, ctx->schnorr_H_g_to_s_signature, ctx->rsa_e, ctx->rsa_n));
// we will actually sign SHA(4^s) to prevent a malleability attack!
CHECK(d0_iobuf_read_packet(in, ctx->msg, &ctx->msglen));
// send challenge
+#ifdef RNG_XKCD
+ CHECK_ASSIGN(ctx->challenge, d0_bignum_int(ctx->challenge, 4)); // decided by fair dice roll
+#else
CHECK_ASSIGN(ctx->challenge, d0_bignum_rand_bit_atmost(ctx->challenge, SCHNORR_BITS));
+#endif
CHECK(d0_iobuf_write_bignum(out, ctx->challenge));
// Diffie Hellmann send
+ LOCKTEMPS();
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
+#ifdef RNG_XKCD
+ CHECK_ASSIGN(ctx->t, d0_bignum_int(ctx->t, 4)); // decided by fair dice roll
+#else
CHECK_ASSIGN(ctx->t, d0_bignum_rand_range(ctx->t, zero, temp0));
+#endif
CHECK(d0_bignum_mod_pow(temp0, four, ctx->t, ctx->schnorr_G));
CHECK(d0_iobuf_write_bignum(out, temp0));
+ UNLOCKTEMPS();
if(status)
*status = !!d0_bignum_cmp(ctx->schnorr_H_g_to_s_signature, zero);
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
d0_iobuf_close(out, outbuflen);
return 0;
d0_iobuf_t *in = NULL;
d0_iobuf_t *out = NULL;
- // temps: 0 order, 1 prod, 2 y, 3 challenge
+ USINGTEMPS(); // temps: 0 order, 1 prod, 2 y, 3 challenge
REPLACING(other_g_to_t); REPLACING(t);
USING(schnorr_G); USING(schnorr_s); USING(r); USING(g_to_t);
in = d0_iobuf_open_read(inbuf, inbuflen);
out = d0_iobuf_open_write(outbuf, *outbuflen);
+ LOCKTEMPS();
CHECK(d0_iobuf_read_bignum(in, temp3));
CHECK(d0_bignum_cmp(temp3, zero) >= 0);
CHECK(d0_bignum_size(temp3) <= SCHNORR_BITS);
// i.challenge. r + ctx->schnorr_s * temp3
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
CHECK(d0_bignum_mod_mul(temp1, ctx->schnorr_s, temp3, temp0));
- CHECK(d0_bignum_mod_add(temp2, temp1, ctx->r, temp0));
+#ifdef D0_BLIND_ID_POSITIVE_PROTOCOL
+ CHECK(d0_bignum_mod_add(temp2, ctx->r, temp1, temp0));
+#else
+ CHECK(d0_bignum_mod_sub(temp2, ctx->r, temp1, temp0));
+#endif
CHECK(d0_iobuf_write_bignum(out, temp2));
+ UNLOCKTEMPS();
// Diffie Hellmann recv
CHECK_ASSIGN(ctx->other_g_to_t, d0_iobuf_read_bignum(in, ctx->other_g_to_t));
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
d0_iobuf_close(out, outbuflen);
return 0;
// (check using H(g^r) which we know)
{
d0_iobuf_t *in = NULL;
- static unsigned char convbuf[1024];
+ static __thread unsigned char convbuf[1024];
d0_iobuf_t *conv = NULL;
size_t sz;
- // temps: 0 y 1 order
+ USINGTEMPS(); // temps: 0 y 1 order
USING(challenge); USING(schnorr_G);
REPLACING(other_g_to_t);
in = d0_iobuf_open_read(inbuf, inbuflen);
+ LOCKTEMPS();
+
CHECK(d0_dl_get_order(temp1, ctx->schnorr_G));
CHECK(d0_iobuf_read_bignum(in, temp0));
CHECK(d0_bignum_cmp(temp0, zero) >= 0);
CHECK(d0_bignum_cmp(temp0, temp1) < 0);
// verify schnorr ID scheme
+#ifdef D0_BLIND_ID_POSITIVE_PROTOCOL
// we need 4^r = 4^temp0 (g^s)^-challenge
CHECK(d0_bignum_mod_inv(temp1, ctx->schnorr_g_to_s, ctx->schnorr_G));
CHECK(d0_bignum_mod_pow(temp2, temp1, ctx->challenge, ctx->schnorr_G));
+#else
+ // we need 4^r = 4^temp0 (g^s)^challenge
+ CHECK(d0_bignum_mod_pow(temp2, ctx->schnorr_g_to_s, ctx->challenge, ctx->schnorr_G));
+#endif
CHECK(d0_bignum_mod_pow(temp1, four, temp0, ctx->schnorr_G));
CHECK_ASSIGN(temp3, d0_bignum_mod_mul(temp3, temp1, temp2, ctx->schnorr_G));
CHECK(d0_iobuf_write_bignum(conv, ctx->other_g_to_t));
CHECK(d0_iobuf_write_packet(conv, ctx->msg, ctx->msglen));
CHECK(d0_iobuf_write_bignum(conv, temp3));
+ UNLOCKTEMPS();
CHECK(d0_iobuf_write_bignum(conv, ctx->other_g_to_t));
d0_iobuf_close(conv, &sz);
conv = NULL;
return 1;
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
return 0;
}
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_authenticate_with_private_id_generate_missing_signature(d0_blind_id_t *ctx)
{
size_t sz;
- static unsigned char shabuf[2048];
+ static __thread unsigned char shabuf[2048];
+ USINGTEMPS(); // temps: 2 hash
REPLACING(schnorr_H_g_to_s_signature);
USING(schnorr_g_to_s); USING(rsa_d); USING(rsa_n);
+ LOCKTEMPS();
+
// we will actually sign SHA(4^s) to prevent a malleability attack!
- CHECK(d0_bignum_mov(temp2, ctx->schnorr_g_to_s));
sz = (d0_bignum_size(ctx->rsa_n) + 7) / 8; // this is too long, so we have to take the value % rsa_n when "decrypting"
if(sz > sizeof(shabuf))
sz = sizeof(shabuf);
- CHECK(d0_longhash_bignum(temp2, shabuf, sz));
+ CHECK(d0_longhash_bignum(ctx->schnorr_g_to_s, shabuf, sz));
+ LOCKTEMPS();
CHECK(d0_bignum_import_unsigned(temp2, shabuf, sz));
// + 7 / 8 is too large, so let's mod it
CHECK(d0_bignum_divmod(NULL, temp1, temp2, ctx->rsa_n));
CHECK(d0_bignum_mod_pow(ctx->schnorr_H_g_to_s_signature, temp1, ctx->rsa_d, ctx->rsa_n));
+
+ UNLOCKTEMPS();
return 1;
fail:
+ UNLOCKTEMPS();
return 0;
}
-D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_sign(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL send_modulus, const char *message, size_t msglen, char *outbuf, size_t *outbuflen)
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_sign_internal(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL send_modulus, D0_BOOL with_msg, const char *message, size_t msglen, char *outbuf, size_t *outbuflen)
{
d0_iobuf_t *out = NULL;
- static unsigned char convbuf[1024];
- static unsigned char shabuf[1024];
+ unsigned char *convbuf = NULL;
+ static __thread unsigned char shabuf[2048];
d0_iobuf_t *conv = NULL;
size_t sz = 0;
+ USINGTEMPS(); // temps: 0 order 1 4^r 2 hash
if(is_first)
{
USING(schnorr_g_to_s); USING(schnorr_H_g_to_s_signature);
// start schnorr SIGNATURE scheme
// generate random number r; x = g^r; send hash of H(m||r), remember r, forget x
+ LOCKTEMPS();
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
CHECK_ASSIGN(ctx->r, d0_bignum_rand_range(ctx->r, zero, temp0));
CHECK(d0_bignum_mod_pow(temp1, four, ctx->r, ctx->schnorr_G));
// hash it, hash it, everybody hash it
- conv = d0_iobuf_open_write(convbuf, sizeof(convbuf));
+ conv = d0_iobuf_open_write_p((void **) &convbuf, 0);
CHECK(d0_iobuf_write_packet(conv, message, msglen));
CHECK(d0_iobuf_write_bignum(conv, temp1));
d0_iobuf_close(conv, &sz);
conv = NULL;
CHECK(d0_longhash_destructive(convbuf, sz, shabuf, (d0_bignum_size(temp0) + 7) / 8));
+ d0_free(convbuf);
+ convbuf = NULL;
CHECK(d0_bignum_import_unsigned(temp2, shabuf, (d0_bignum_size(temp0) + 7) / 8));
CHECK(d0_iobuf_write_bignum(out, temp2));
// multiply with secret, sub k, modulo order
CHECK(d0_bignum_mod_mul(temp1, temp2, ctx->schnorr_s, temp0));
+#ifdef D0_BLIND_ID_POSITIVE_PROTOCOL
+ CHECK(d0_bignum_mod_add(temp2, ctx->r, temp1, temp0));
+#else
CHECK(d0_bignum_mod_sub(temp2, ctx->r, temp1, temp0));
+#endif
CHECK(d0_iobuf_write_bignum(out, temp2));
+ UNLOCKTEMPS();
// write the message itself
- CHECK(d0_iobuf_write_packet(out, message, msglen));
+ if(with_msg)
+ CHECK(d0_iobuf_write_packet(out, message, msglen));
return d0_iobuf_close(out, outbuflen);
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(out, outbuflen);
return 0;
}
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_sign(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL send_modulus, const char *message, size_t msglen, char *outbuf, size_t *outbuflen)
+{
+ return d0_blind_id_sign_with_private_id_sign_internal(ctx, is_first, send_modulus, 1, message, msglen, outbuf, outbuflen);
+}
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_sign_detached(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL send_modulus, const char *message, size_t msglen, char *outbuf, size_t *outbuflen)
+{
+ return d0_blind_id_sign_with_private_id_sign_internal(ctx, is_first, send_modulus, 0, message, msglen, outbuf, outbuflen);
+}
-D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_verify(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL recv_modulus, const char *inbuf, size_t inbuflen, char *msg, size_t *msglen, D0_BOOL *status)
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_verify_internal(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL recv_modulus, D0_BOOL with_msg, const char *inbuf, size_t inbuflen, char *msg, size_t *msglen, D0_BOOL *status)
{
d0_iobuf_t *in = NULL;
d0_iobuf_t *conv = NULL;
- static unsigned char convbuf[2048];
- static unsigned char shabuf[2048];
+ unsigned char *convbuf = NULL;
+ static __thread unsigned char shabuf[2048];
size_t sz;
+ USINGTEMPS(); // temps: 0 sig^e 2 g^s 3 g^-s 4 order
if(is_first)
{
REPLACING(schnorr_g_to_s); REPLACING(schnorr_H_g_to_s_signature);
CHECK(d0_bignum_cmp(ctx->schnorr_H_g_to_s_signature, ctx->rsa_n) < 0);
// check signature of key (t = k^d, so, t^challenge = k)
+ LOCKTEMPS();
CHECK(d0_bignum_mod_pow(temp0, ctx->schnorr_H_g_to_s_signature, ctx->rsa_e, ctx->rsa_n));
// we will actually sign SHA(4^s) to prevent a malleability attack!
- CHECK(d0_bignum_mov(temp2, ctx->schnorr_g_to_s));
sz = (d0_bignum_size(ctx->rsa_n) + 7) / 8; // this is too long, so we have to take the value % rsa_n when "decrypting"
if(sz > sizeof(shabuf))
sz = sizeof(shabuf);
- CHECK(d0_longhash_bignum(temp2, shabuf, sz));
+ CHECK(d0_longhash_bignum(ctx->schnorr_g_to_s, shabuf, sz));
CHECK(d0_bignum_import_unsigned(temp2, shabuf, sz));
// + 7 / 8 is too large, so let's mod it
CHECK(d0_dl_get_order(temp4, ctx->schnorr_G));
CHECK(d0_iobuf_read_bignum(in, temp0)); // e == H(m || g^r)
CHECK(d0_iobuf_read_bignum(in, temp1)); // x == (r - s*e) mod |G|
- CHECK(d0_iobuf_read_packet(in, msg, msglen));
+ if(with_msg)
+ CHECK(d0_iobuf_read_packet(in, msg, msglen));
// VERIFY: g^x * (g^s)^-e = g^(x - s*e) = g^r
// verify schnorr ID scheme
// we need g^r = g^x (g^s)^e
CHECK(d0_bignum_mod_pow(temp2, four, temp1, ctx->schnorr_G));
+#ifdef D0_BLIND_ID_POSITIVE_PROTOCOL
+ CHECK(d0_bignum_mod_inv(temp3, ctx->schnorr_g_to_s, ctx->schnorr_G));
+ CHECK(d0_bignum_mod_pow(temp1, temp3, temp0, ctx->schnorr_G));
+#else
CHECK(d0_bignum_mod_pow(temp1, ctx->schnorr_g_to_s, temp0, ctx->schnorr_G));
+#endif
CHECK_ASSIGN(temp3, d0_bignum_mod_mul(temp3, temp1, temp2, ctx->schnorr_G)); // temp3 now is g^r
// hash it, hash it, everybody hash it
- conv = d0_iobuf_open_write(convbuf, sizeof(convbuf));
+ conv = d0_iobuf_open_write_p((void **) &convbuf, 0);
CHECK(d0_iobuf_write_packet(conv, msg, *msglen));
CHECK(d0_iobuf_write_bignum(conv, temp3));
d0_iobuf_close(conv, &sz);
conv = NULL;
CHECK(d0_longhash_destructive(convbuf, sz, shabuf, (d0_bignum_size(temp4) + 7) / 8));
+ d0_free(convbuf);
+ convbuf = NULL;
CHECK(d0_bignum_import_unsigned(temp1, shabuf, (d0_bignum_size(temp4) + 7) / 8));
// verify signature
CHECK(!d0_bignum_cmp(temp0, temp1));
+ UNLOCKTEMPS();
if(status)
*status = !!d0_bignum_cmp(ctx->schnorr_H_g_to_s_signature, zero);
return 1;
fail:
+ UNLOCKTEMPS();
d0_iobuf_close(in, NULL);
return 0;
}
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_verify(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL recv_modulus, const char *inbuf, size_t inbuflen, char *msg, size_t *msglen, D0_BOOL *status)
+{
+ return d0_blind_id_sign_with_private_id_verify_internal(ctx, is_first, recv_modulus, 1, inbuf, inbuflen, msg, msglen, status);
+}
+D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_sign_with_private_id_verify_detached(d0_blind_id_t *ctx, D0_BOOL is_first, D0_BOOL recv_modulus, const char *inbuf, size_t inbuflen, const char *msg, size_t msglen, D0_BOOL *status)
+{
+ return d0_blind_id_sign_with_private_id_verify_internal(ctx, is_first, recv_modulus, 0, inbuf, inbuflen, (char *) msg, &msglen, status);
+}
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_fingerprint64_public_id(const d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
d0_iobuf_t *out = NULL;
- static unsigned char convbuf[1024];
+ static __thread unsigned char convbuf[1024];
d0_iobuf_t *conv = NULL;
size_t sz, n;
D0_BOOL d0_blind_id_sessionkey_public_id(const d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
+ D0_BOOL ret;
+
+ USINGTEMPS(); // temps: temp0 result
USING(t); USING(other_g_to_t); USING(schnorr_G);
- // temps: temp0 result
+ LOCKTEMPS();
CHECK(d0_bignum_mod_pow(temp0, ctx->other_g_to_t, ctx->t, ctx->schnorr_G));
- return d0_longhash_bignum(temp0, (unsigned char *) outbuf, *outbuflen);
+ ret = d0_longhash_bignum(temp0, (unsigned char *) outbuf, *outbuflen);
+ UNLOCKTEMPS();
+ return ret;
fail:
+ UNLOCKTEMPS();
return 0;
}
projects / xonotic / d0_blind_id.git / blobdiff