d0_bignum_t *e; // challenge
char msg[MSGSIZE]; // message
size_t msglen; // message length
+ d0_bignum_t *other_4_to_r; // for DH key exchange
};
#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 USING(x) if(!(ctx->x)) return 0
+#define REPLACING(x)
+
static d0_bignum_t *zero, *one, *four, *temp0, *temp1, *temp2, *temp3, *temp4;
void d0_blind_id_INITIALIZE(void)
if(ctx->rn) d0_bignum_free(ctx->rn);
if(ctx->r) d0_bignum_free(ctx->r);
if(ctx->e) d0_bignum_free(ctx->e);
+ if(ctx->other_4_to_r) d0_bignum_free(ctx->other_4_to_r);
memset(ctx, 0, sizeof(*ctx));
}
if(src->rn) ctx->rn = d0_bignum_mov(NULL, src->rn);
if(src->r) ctx->r = d0_bignum_mov(NULL, src->r);
if(src->e) ctx->e = d0_bignum_mov(NULL, src->e);
- // TODO xnbh, msg, msglen?
+ if(src->other_4_to_r) ctx->other_4_to_r = d0_bignum_mov(NULL, src->other_4_to_r);
+ memcpy(ctx->msg, src->msg, sizeof(ctx->msg));
+ ctx->msglen = src->msglen;
+ memcpy(ctx->xnbh, src->xnbh, sizeof(ctx->xnbh));
}
WARN_UNUSED_RESULT BOOL d0_blind_id_generate_private_key(d0_blind_id_t *ctx, int k)
{
- d0_blind_id_clear(ctx);
+ 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));
WARN_UNUSED_RESULT BOOL d0_blind_id_read_private_key(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in = d0_iobuf_open_read(inbuf, inbuflen);
+ d0_iobuf_t *in = NULL;
+
+ REPLACING(rsa_n); REPLACING(rsa_e); REPLACING(rsa_d);
+
+ in = d0_iobuf_open_read(inbuf, inbuflen);
+
CHECK_ASSIGN(ctx->rsa_n, d0_iobuf_read_bignum(in, ctx->rsa_n));
CHECK_ASSIGN(ctx->rsa_e, d0_iobuf_read_bignum(in, ctx->rsa_e));
CHECK_ASSIGN(ctx->rsa_d, d0_iobuf_read_bignum(in, ctx->rsa_d));
WARN_UNUSED_RESULT BOOL d0_blind_id_read_public_key(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in = d0_iobuf_open_read(inbuf, inbuflen);
+ d0_iobuf_t *in = NULL;
+
+ REPLACING(rsa_n); REPLACING(rsa_e);
+
+ in = d0_iobuf_open_read(inbuf, inbuflen);
CHECK_ASSIGN(ctx->rsa_n, d0_iobuf_read_bignum(in, ctx->rsa_n));
CHECK_ASSIGN(ctx->rsa_e, d0_iobuf_read_bignum(in, ctx->rsa_e));
return d0_iobuf_close(in, NULL);
return 0;
}
-#define USING(x) if(!(ctx->x)) return 0
-#define REPLACING(x)
-
WARN_UNUSED_RESULT BOOL d0_blind_id_write_private_key(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
USING(rsa_n); USING(rsa_e); USING(rsa_d);
WARN_UNUSED_RESULT BOOL d0_blind_id_write_public_key(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
USING(rsa_n); USING(rsa_e);
WARN_UNUSED_RESULT BOOL d0_blind_id_read_private_id_modulus(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in = d0_iobuf_open_read(inbuf, inbuflen);
+ d0_iobuf_t *in = NULL;
+
+ REPLACING(schnorr_G);
+
+ in = d0_iobuf_open_read(inbuf, inbuflen);
CHECK_ASSIGN(ctx->schnorr_G, d0_iobuf_read_bignum(in, ctx->schnorr_G));
return d0_iobuf_close(in, NULL);
WARN_UNUSED_RESULT BOOL d0_blind_id_write_private_id_modulus(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
USING(schnorr_G);
WARN_UNUSED_RESULT BOOL d0_blind_id_generate_private_id_start(d0_blind_id_t *ctx)
{
- // temps: temp0 order
+ // temps: temp0 = order
USING(schnorr_G);
REPLACING(schnorr_s); REPLACING(schnorr_4_to_s);
WARN_UNUSED_RESULT BOOL d0_blind_id_generate_private_id_request(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
- // temps: temp0 temp1
+ // temps: temp0 rn^e, temp1 (4^s)*rn^e
USING(rsa_n); USING(rsa_e); USING(schnorr_4_to_s);
REPLACING(rn);
WARN_UNUSED_RESULT BOOL d0_blind_id_answer_private_id_request(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *in;
- d0_iobuf_t *out;
+ d0_iobuf_t *in = NULL;
+ d0_iobuf_t *out = NULL;
- // temps: temp0 temp1
+ // temps: temp0 input, temp1 temp0^d
USING(rsa_d); USING(rsa_n);
in = d0_iobuf_open_read(inbuf, inbuflen);
WARN_UNUSED_RESULT BOOL d0_blind_id_finish_private_id_request(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in;
+ d0_iobuf_t *in = NULL;
- // temps: temp0 temp1
+ // temps: temp0 input, temp1 rn^-1
USING(rn); USING(rsa_n);
REPLACING(schnorr_4_to_s_signature);
WARN_UNUSED_RESULT BOOL d0_blind_id_read_private_id(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in;
+ d0_iobuf_t *in = NULL;
REPLACING(schnorr_s); REPLACING(schnorr_4_to_s); REPLACING(schnorr_4_to_s_signature);
WARN_UNUSED_RESULT BOOL d0_blind_id_read_public_id(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen)
{
- d0_iobuf_t *in;
+ d0_iobuf_t *in = NULL;
REPLACING(schnorr_4_to_s); REPLACING(schnorr_4_to_s_signature);
WARN_UNUSED_RESULT BOOL d0_blind_id_write_private_id(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
USING(schnorr_s); USING(schnorr_4_to_s); USING(schnorr_4_to_s_signature);
WARN_UNUSED_RESULT BOOL d0_blind_id_write_public_id(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
+ d0_iobuf_t *out = NULL;
USING(schnorr_4_to_s); USING(schnorr_4_to_s_signature);
// first run: send 4^s, 4^s signature
// 1. get random r, send HASH(4^r)
{
- d0_iobuf_t *out;
- unsigned char convbuf[1024];
- d0_iobuf_t *conv;
- size_t sz;
+ d0_iobuf_t *out = NULL;
+ static unsigned char convbuf[1024];
+ d0_iobuf_t *conv = NULL;
+ size_t sz = 0;
+ // temps: temp0 order, temp0 4^r
if(is_first)
{
USING(schnorr_4_to_s); USING(schnorr_4_to_s_signature);
// 2. save HASH(4^r)
// 3. send challenge e of SCHNORR_BITS
{
- d0_iobuf_t *in;
- d0_iobuf_t *out;
+ d0_iobuf_t *in = NULL;
+ d0_iobuf_t *out = NULL;
+ // temps: temp0 order, temp0 signature check
if(is_first)
{
- REPLACING(schnorr_4_to_s); REPLACING(k); REPLACING(schnorr_4_to_s_signature);
- USING(rsa_n);
- if(!recv_modulus)
+ REPLACING(schnorr_4_to_s); REPLACING(schnorr_4_to_s_signature);
+ if(recv_modulus)
+ REPLACING(schnorr_G);
+ else
USING(schnorr_G);
}
else
{
- USING(schnorr_4_to_s_signature); USING(schnorr_4_to_s);
+ USING(schnorr_4_to_s); USING(schnorr_4_to_s_signature);
USING(schnorr_G);
}
USING(rsa_e); USING(rsa_n);
- REPLACING(e); REPLACING(msg); REPLACING(msglen);
+ REPLACING(e); REPLACING(msg); REPLACING(msglen); REPLACING(xnbh); REPLACING(r);
in = d0_iobuf_open_read(inbuf, inbuflen);
out = d0_iobuf_open_write(outbuf, *outbuflen);
CHECK(d0_iobuf_write_bignum(out, ctx->e));
+ // Diffie Hellmann
+ 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(temp0, four, ctx->r, ctx->schnorr_G));
+ CHECK(d0_iobuf_write_bignum(out, temp0));
+
if(status)
*status = !!d0_bignum_cmp(ctx->schnorr_4_to_s_signature, zero);
// 1. read challenge e of SCHNORR_BITS
// 2. reply with r + s * e mod order
{
- d0_iobuf_t *in;
- d0_iobuf_t *out;
+ d0_iobuf_t *in = NULL;
+ d0_iobuf_t *out = NULL;
// temps: 0 order, 1 prod, 2 y, 3 e
+ REPLACING(other_4_to_r);
USING(schnorr_G); USING(schnorr_s); USING(r);
in = d0_iobuf_open_read(inbuf, inbuflen);
out = d0_iobuf_open_write(outbuf, *outbuflen);
CHECK(d0_iobuf_read_bignum(in, temp3));
- // TODO check if >= 2^SCHNORR_BITS or < 0, if yes, then fail (needed for zero knowledge)
CHECK(d0_bignum_cmp(temp3, zero) >= 0);
CHECK(d0_bignum_size(temp3) <= SCHNORR_BITS);
+ // Diffie Hellmann
+ CHECK_ASSIGN(ctx->other_4_to_r, d0_iobuf_read_bignum(in, ctx->other_4_to_r));
+ CHECK(d0_bignum_cmp(ctx->other_4_to_r, zero) > 0);
+ CHECK(d0_bignum_cmp(ctx->other_4_to_r, ctx->schnorr_G) < 0);
+
// send response for schnorr ID scheme
// i.e. r + ctx->schnorr_s * temp3
CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
return 0;
}
-WARN_UNUSED_RESULT BOOL d0_blind_id_authenticate_with_private_id_verify(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen, char *msg, ssize_t *msglen, BOOL *status)
+WARN_UNUSED_RESULT BOOL d0_blind_id_authenticate_with_private_id_verify(d0_blind_id_t *ctx, const char *inbuf, size_t inbuflen, char *msg, size_t *msglen, BOOL *status)
// 1. read y = r + s * e mod order
// 2. verify: g^y (g^s)^-e = g^(r+s*e-s*e) = g^r
// (check using H(g^r) which we know)
{
- d0_iobuf_t *in;
- unsigned char convbuf[1024];
- d0_iobuf_t *conv;
+ d0_iobuf_t *in = NULL;
+ static unsigned char convbuf[1024];
+ d0_iobuf_t *conv = NULL;
size_t sz;
// temps: 0 y 1 order
USING(e); USING(schnorr_G);
+ REPLACING(other_4_to_r);
in = d0_iobuf_open_read(inbuf, inbuflen);
- *msglen = -1;
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_neg(temp1, ctx->e));
CHECK(d0_bignum_mod_pow(temp2, ctx->schnorr_4_to_s, temp1, ctx->schnorr_G));
CHECK(d0_bignum_mod_pow(temp1, four, temp0, ctx->schnorr_G));
- CHECK(d0_bignum_mod_mul(temp3, temp1, temp2, ctx->schnorr_G));
+ CHECK_ASSIGN(ctx->other_4_to_r, d0_bignum_mod_mul(ctx->other_4_to_r, temp1, temp2, ctx->schnorr_G));
// hash must be equal to xnbh
// hash it, hash it, everybody hash it
conv = d0_iobuf_open_write(convbuf, sizeof(convbuf));
- CHECK(d0_iobuf_write_bignum(conv, temp3));
+ CHECK(d0_iobuf_write_bignum(conv, ctx->other_4_to_r));
CHECK(d0_iobuf_write_packet(conv, ctx->msg, ctx->msglen));
- CHECK(d0_iobuf_write_bignum(conv, temp3));
+ CHECK(d0_iobuf_write_bignum(conv, ctx->other_4_to_r));
d0_iobuf_close(conv, &sz);
conv = NULL;
if(memcmp(sha(convbuf, sz), ctx->xnbh, SCHNORR_HASHSIZE))
if(status)
*status = !!d0_bignum_cmp(ctx->schnorr_4_to_s_signature, zero);
- if(ctx->msglen <= (size_t) *msglen)
+ if(ctx->msglen <= *msglen)
memcpy(msg, ctx->msg, ctx->msglen);
else
memcpy(msg, ctx->msg, *msglen);
WARN_UNUSED_RESULT BOOL d0_blind_id_fingerprint64_public_id(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
{
- d0_iobuf_t *out;
- d0_iobuf_t *conv;
+ d0_iobuf_t *out = NULL;
static unsigned char convbuf[1024];
+ d0_iobuf_t *conv = NULL;
size_t sz, n;
USING(schnorr_4_to_s);
n = (*outbuflen / 4) * 3;
if(n > SHA_DIGESTSIZE)
n = SHA_DIGESTSIZE;
- if(d0_iobuf_write_raw(out, sha(convbuf, sz), n) != n)
- goto fail;
- if(!d0_iobuf_conv_base64_out(out))
- goto fail;
+ CHECK(d0_iobuf_write_raw(out, sha(convbuf, sz), n) == n);
+ CHECK(d0_iobuf_conv_base64_out(out));
return d0_iobuf_close(out, outbuflen);
fail:
if(conv)
- if(!d0_iobuf_close(conv, &sz)) { }
- if(!d0_iobuf_close(out, outbuflen))
- return 0;
+ d0_iobuf_close(conv, &sz);
+ d0_iobuf_close(out, outbuflen);
+ return 0;
+}
+
+BOOL d0_blind_id_sessionkey_public_id(d0_blind_id_t *ctx, char *outbuf, size_t *outbuflen)
+{
+ d0_iobuf_t *out = NULL;
+ static unsigned char convbuf[1024];
+ d0_iobuf_t *conv = NULL;
+ size_t n, sz;
+
+ USING(r); USING(other_4_to_r); USING(schnorr_G);
+
+ out = d0_iobuf_open_write(outbuf, *outbuflen);
+ conv = d0_iobuf_open_write(convbuf, sizeof(convbuf));
+
+ // temps: temp0 result
+ CHECK(d0_bignum_mod_pow(temp0, ctx->other_4_to_r, ctx->r, ctx->schnorr_G));
+ CHECK(d0_iobuf_write_bignum(conv, temp0));
+ CHECK(d0_iobuf_close(conv, &sz));
+ conv = NULL;
+
+ n = *outbuflen;
+ if(n > SHA_DIGESTSIZE)
+ n = SHA_DIGESTSIZE;
+ CHECK(d0_iobuf_write_raw(out, sha(convbuf, sz), n) == n);
+
+ return d0_iobuf_close(out, outbuflen);
+
+fail:
+ if(conv)
+ d0_iobuf_close(conv, &sz);
+ d0_iobuf_close(out, outbuflen);
return 0;
}
projects / xonotic / d0_blind_id.git / blobdiff