#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];
+ 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;
+static d0_bignum_t *zero, *one, *four;
+static d0_bignum_t *temp0, *temp1, *temp2, *temp3, *temp4; // FIXME make these thread safe by putting them in some per-thread object
D0_WARN_UNUSED_RESULT D0_BOOL d0_blind_id_INITIALIZE(void)
{
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_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_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
// 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;
// start schnorr ID scheme
// generate random number r; x = g^r; send hash of x, remember r, forget x
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));
{
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
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
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));
// 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));
// Diffie Hellmann recv
// (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;
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));
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];
REPLACING(schnorr_H_g_to_s_signature);
USING(schnorr_g_to_s); USING(rsa_d); USING(rsa_n);
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;
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));
// 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);
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;
if(is_first)
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
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;
projects / xonotic / d0_blind_id.git / blobdiff