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Diffstat (limited to 'openssl/demos/jpake/jpakedemo.c')
-rw-r--r--openssl/demos/jpake/jpakedemo.c469
1 files changed, 0 insertions, 469 deletions
diff --git a/openssl/demos/jpake/jpakedemo.c b/openssl/demos/jpake/jpakedemo.c
deleted file mode 100644
index 338a8810d..000000000
--- a/openssl/demos/jpake/jpakedemo.c
+++ /dev/null
@@ -1,469 +0,0 @@
-#include "openssl/bn.h"
-#include "openssl/sha.h"
-#include <assert.h>
-#include <string.h>
-#include <stdlib.h>
-
-/* Copyright (C) 2008 Ben Laurie (ben@links.org) */
-
-/*
- * Implement J-PAKE, as described in
- * http://grouper.ieee.org/groups/1363/Research/contributions/hao-ryan-2008.pdf
- *
- * With hints from http://www.cl.cam.ac.uk/~fh240/software/JPAKE2.java.
- */
-
-static void showbn(const char *name, const BIGNUM *bn)
- {
- fputs(name, stdout);
- fputs(" = ", stdout);
- BN_print_fp(stdout, bn);
- putc('\n', stdout);
- }
-
-typedef struct
- {
- BN_CTX *ctx; // Perhaps not the best place for this?
- BIGNUM *p;
- BIGNUM *q;
- BIGNUM *g;
- } JPakeParameters;
-
-static void JPakeParametersInit(JPakeParameters *params)
- {
- params->ctx = BN_CTX_new();
-
- // For now use p, q, g from Java sample code. Later, generate them.
- params->p = NULL;
- BN_hex2bn(&params->p, "fd7f53811d75122952df4a9c2eece4e7f611b7523cef4400c31e3f80b6512669455d402251fb593d8d58fabfc5f5ba30f6cb9b556cd7813b801d346ff26660b76b9950a5a49f9fe8047b1022c24fbba9d7feb7c61bf83b57e7c6a8a6150f04fb83f6d3c51ec3023554135a169132f675f3ae2b61d72aeff22203199dd14801c7");
- params->q = NULL;
- BN_hex2bn(&params->q, "9760508f15230bccb292b982a2eb840bf0581cf5");
- params->g = NULL;
- BN_hex2bn(&params->g, "f7e1a085d69b3ddecbbcab5c36b857b97994afbbfa3aea82f9574c0b3d0782675159578ebad4594fe67107108180b449167123e84c281613b7cf09328cc8a6e13c167a8b547c8d28e0a3ae1e2bb3a675916ea37f0bfa213562f1fb627a01243bcca4f1bea8519089a883dfe15ae59f06928b665e807b552564014c3bfecf492a");
-
- showbn("p", params->p);
- showbn("q", params->q);
- showbn("g", params->g);
- }
-
-typedef struct
- {
- BIGNUM *gr; // g^r (r random)
- BIGNUM *b; // b = r - x*h, h=hash(g, g^r, g^x, name)
- } JPakeZKP;
-
-typedef struct
- {
- BIGNUM *gx; // g^x
- JPakeZKP zkpx; // ZKP(x)
- } JPakeStep1;
-
-typedef struct
- {
- BIGNUM *X; // g^(xa + xc + xd) * xb * s
- JPakeZKP zkpxbs; // ZKP(xb * s)
- } JPakeStep2;
-
-typedef struct
- {
- const char *name; // Must be unique
- int base; // 1 for Alice, 3 for Bob. Only used for printing stuff.
- JPakeStep1 s1c; // Alice's g^x3, ZKP(x3) or Bob's g^x1, ZKP(x1)
- JPakeStep1 s1d; // Alice's g^x4, ZKP(x4) or Bob's g^x2, ZKP(x2)
- JPakeStep2 s2; // Alice's A, ZKP(x2 * s) or Bob's B, ZKP(x4 * s)
- } JPakeUserPublic;
-
-/*
- * The user structure. In the definition, (xa, xb, xc, xd) are Alice's
- * (x1, x2, x3, x4) or Bob's (x3, x4, x1, x2). If you see what I mean.
- */
-typedef struct
- {
- JPakeUserPublic p;
- BIGNUM *secret; // The shared secret
- BIGNUM *key; // The calculated (shared) key
- BIGNUM *xa; // Alice's x1 or Bob's x3
- BIGNUM *xb; // Alice's x2 or Bob's x4
- } JPakeUser;
-
-// Generate each party's random numbers. xa is in [0, q), xb is in [1, q).
-static void genrand(JPakeUser *user, const JPakeParameters *params)
- {
- BIGNUM *qm1;
-
- // xa in [0, q)
- user->xa = BN_new();
- BN_rand_range(user->xa, params->q);
-
- // q-1
- qm1 = BN_new();
- BN_copy(qm1, params->q);
- BN_sub_word(qm1, 1);
-
- // ... and xb in [0, q-1)
- user->xb = BN_new();
- BN_rand_range(user->xb, qm1);
- // [1, q)
- BN_add_word(user->xb, 1);
-
- // cleanup
- BN_free(qm1);
-
- // Show
- printf("x%d", user->p.base);
- showbn("", user->xa);
- printf("x%d", user->p.base+1);
- showbn("", user->xb);
- }
-
-static void hashlength(SHA_CTX *sha, size_t l)
- {
- unsigned char b[2];
-
- assert(l <= 0xffff);
- b[0] = l >> 8;
- b[1] = l&0xff;
- SHA1_Update(sha, b, 2);
- }
-
-static void hashstring(SHA_CTX *sha, const char *string)
- {
- size_t l = strlen(string);
-
- hashlength(sha, l);
- SHA1_Update(sha, string, l);
- }
-
-static void hashbn(SHA_CTX *sha, const BIGNUM *bn)
- {
- size_t l = BN_num_bytes(bn);
- unsigned char *bin = alloca(l);
-
- hashlength(sha, l);
- BN_bn2bin(bn, bin);
- SHA1_Update(sha, bin, l);
- }
-
-// h=hash(g, g^r, g^x, name)
-static void zkpHash(BIGNUM *h, const JPakeZKP *zkp, const BIGNUM *gx,
- const JPakeUserPublic *from, const JPakeParameters *params)
- {
- unsigned char md[SHA_DIGEST_LENGTH];
- SHA_CTX sha;
-
- // XXX: hash should not allow moving of the boundaries - Java code
- // is flawed in this respect. Length encoding seems simplest.
- SHA1_Init(&sha);
- hashbn(&sha, params->g);
- hashbn(&sha, zkp->gr);
- hashbn(&sha, gx);
- hashstring(&sha, from->name);
- SHA1_Final(md, &sha);
- BN_bin2bn(md, SHA_DIGEST_LENGTH, h);
- }
-
-// Prove knowledge of x
-// Note that we don't send g^x because, as it happens, we've always
-// sent it elsewhere. Also note that because of that, we could avoid
-// calculating it here, but we don't, for clarity...
-static void CreateZKP(JPakeZKP *zkp, const BIGNUM *x, const JPakeUser *us,
- const BIGNUM *zkpg, const JPakeParameters *params,
- int n, const char *suffix)
- {
- BIGNUM *r = BN_new();
- BIGNUM *gx = BN_new();
- BIGNUM *h = BN_new();
- BIGNUM *t = BN_new();
-
- // r in [0,q)
- // XXX: Java chooses r in [0, 2^160) - i.e. distribution not uniform
- BN_rand_range(r, params->q);
- // g^r
- zkp->gr = BN_new();
- BN_mod_exp(zkp->gr, zkpg, r, params->p, params->ctx);
- // g^x
- BN_mod_exp(gx, zkpg, x, params->p, params->ctx);
-
- // h=hash...
- zkpHash(h, zkp, gx, &us->p, params);
-
- // b = r - x*h
- BN_mod_mul(t, x, h, params->q, params->ctx);
- zkp->b = BN_new();
- BN_mod_sub(zkp->b, r, t, params->q, params->ctx);
-
- // show
- printf(" ZKP(x%d%s)\n", n, suffix);
- showbn(" zkpg", zkpg);
- showbn(" g^x", gx);
- showbn(" g^r", zkp->gr);
- showbn(" b", zkp->b);
-
- // cleanup
- BN_free(t);
- BN_free(h);
- BN_free(gx);
- BN_free(r);
- }
-
-static int VerifyZKP(const JPakeZKP *zkp, BIGNUM *gx,
- const JPakeUserPublic *them, const BIGNUM *zkpg,
- const JPakeParameters *params, int n, const char *suffix)
- {
- BIGNUM *h = BN_new();
- BIGNUM *t1 = BN_new();
- BIGNUM *t2 = BN_new();
- BIGNUM *t3 = BN_new();
- int ret = 0;
-
- zkpHash(h, zkp, gx, them, params);
-
- // t1 = g^b
- BN_mod_exp(t1, zkpg, zkp->b, params->p, params->ctx);
- // t2 = (g^x)^h = g^{hx}
- BN_mod_exp(t2, gx, h, params->p, params->ctx);
- // t3 = t1 * t2 = g^{hx} * g^b = g^{hx+b} = g^r (allegedly)
- BN_mod_mul(t3, t1, t2, params->p, params->ctx);
-
- printf(" ZKP(x%d%s)\n", n, suffix);
- showbn(" zkpg", zkpg);
- showbn(" g^r'", t3);
-
- // verify t3 == g^r
- if(BN_cmp(t3, zkp->gr) == 0)
- ret = 1;
-
- // cleanup
- BN_free(t3);
- BN_free(t2);
- BN_free(t1);
- BN_free(h);
-
- if(ret)
- puts(" OK");
- else
- puts(" FAIL");
-
- return ret;
- }
-
-static void sendstep1_substep(JPakeStep1 *s1, const BIGNUM *x,
- const JPakeUser *us,
- const JPakeParameters *params, int n)
- {
- s1->gx = BN_new();
- BN_mod_exp(s1->gx, params->g, x, params->p, params->ctx);
- printf(" g^{x%d}", n);
- showbn("", s1->gx);
-
- CreateZKP(&s1->zkpx, x, us, params->g, params, n, "");
- }
-
-static void sendstep1(const JPakeUser *us, JPakeUserPublic *them,
- const JPakeParameters *params)
- {
- printf("\n%s sends %s:\n\n", us->p.name, them->name);
-
- // from's g^xa (which becomes to's g^xc) and ZKP(xa)
- sendstep1_substep(&them->s1c, us->xa, us, params, us->p.base);
- // from's g^xb (which becomes to's g^xd) and ZKP(xb)
- sendstep1_substep(&them->s1d, us->xb, us, params, us->p.base+1);
- }
-
-static int verifystep1(const JPakeUser *us, const JPakeUserPublic *them,
- const JPakeParameters *params)
- {
- printf("\n%s verifies %s:\n\n", us->p.name, them->name);
-
- // verify their ZKP(xc)
- if(!VerifyZKP(&us->p.s1c.zkpx, us->p.s1c.gx, them, params->g, params,
- them->base, ""))
- return 0;
-
- // verify their ZKP(xd)
- if(!VerifyZKP(&us->p.s1d.zkpx, us->p.s1d.gx, them, params->g, params,
- them->base+1, ""))
- return 0;
-
- // g^xd != 1
- printf(" g^{x%d} != 1: ", them->base+1);
- if(BN_is_one(us->p.s1d.gx))
- {
- puts("FAIL");
- return 0;
- }
- puts("OK");
-
- return 1;
- }
-
-static void sendstep2(const JPakeUser *us, JPakeUserPublic *them,
- const JPakeParameters *params)
- {
- BIGNUM *t1 = BN_new();
- BIGNUM *t2 = BN_new();
-
- printf("\n%s sends %s:\n\n", us->p.name, them->name);
-
- // X = g^{(xa + xc + xd) * xb * s}
- // t1 = g^xa
- BN_mod_exp(t1, params->g, us->xa, params->p, params->ctx);
- // t2 = t1 * g^{xc} = g^{xa} * g^{xc} = g^{xa + xc}
- BN_mod_mul(t2, t1, us->p.s1c.gx, params->p, params->ctx);
- // t1 = t2 * g^{xd} = g^{xa + xc + xd}
- BN_mod_mul(t1, t2, us->p.s1d.gx, params->p, params->ctx);
- // t2 = xb * s
- BN_mod_mul(t2, us->xb, us->secret, params->q, params->ctx);
- // X = t1^{t2} = t1^{xb * s} = g^{(xa + xc + xd) * xb * s}
- them->s2.X = BN_new();
- BN_mod_exp(them->s2.X, t1, t2, params->p, params->ctx);
-
- // Show
- printf(" g^{(x%d + x%d + x%d) * x%d * s)", us->p.base, them->base,
- them->base+1, us->p.base+1);
- showbn("", them->s2.X);
-
- // ZKP(xb * s)
- // XXX: this is kinda funky, because we're using
- //
- // g' = g^{xa + xc + xd}
- //
- // as the generator, which means X is g'^{xb * s}
- CreateZKP(&them->s2.zkpxbs, t2, us, t1, params, us->p.base+1, " * s");
-
- // cleanup
- BN_free(t1);
- BN_free(t2);
- }
-
-static int verifystep2(const JPakeUser *us, const JPakeUserPublic *them,
- const JPakeParameters *params)
- {
- BIGNUM *t1 = BN_new();
- BIGNUM *t2 = BN_new();
- int ret = 0;
-
- printf("\n%s verifies %s:\n\n", us->p.name, them->name);
-
- // g' = g^{xc + xa + xb} [from our POV]
- // t1 = xa + xb
- BN_mod_add(t1, us->xa, us->xb, params->q, params->ctx);
- // t2 = g^{t1} = g^{xa+xb}
- BN_mod_exp(t2, params->g, t1, params->p, params->ctx);
- // t1 = g^{xc} * t2 = g^{xc + xa + xb}
- BN_mod_mul(t1, us->p.s1c.gx, t2, params->p, params->ctx);
-
- if(VerifyZKP(&us->p.s2.zkpxbs, us->p.s2.X, them, t1, params, them->base+1,
- " * s"))
- ret = 1;
-
- // cleanup
- BN_free(t2);
- BN_free(t1);
-
- return ret;
- }
-
-static void computekey(JPakeUser *us, const JPakeParameters *params)
- {
- BIGNUM *t1 = BN_new();
- BIGNUM *t2 = BN_new();
- BIGNUM *t3 = BN_new();
-
- printf("\n%s calculates the shared key:\n\n", us->p.name);
-
- // K = (X/g^{xb * xd * s})^{xb}
- // = (g^{(xc + xa + xb) * xd * s - xb * xd *s})^{xb}
- // = (g^{(xa + xc) * xd * s})^{xb}
- // = g^{(xa + xc) * xb * xd * s}
- // [which is the same regardless of who calculates it]
-
- // t1 = (g^{xd})^{xb} = g^{xb * xd}
- BN_mod_exp(t1, us->p.s1d.gx, us->xb, params->p, params->ctx);
- // t2 = -s = q-s
- BN_sub(t2, params->q, us->secret);
- // t3 = t1^t2 = g^{-xb * xd * s}
- BN_mod_exp(t3, t1, t2, params->p, params->ctx);
- // t1 = X * t3 = X/g^{xb * xd * s}
- BN_mod_mul(t1, us->p.s2.X, t3, params->p, params->ctx);
- // K = t1^{xb}
- us->key = BN_new();
- BN_mod_exp(us->key, t1, us->xb, params->p, params->ctx);
-
- // show
- showbn(" K", us->key);
-
- // cleanup
- BN_free(t3);
- BN_free(t2);
- BN_free(t1);
- }
-
-int main(int argc, char **argv)
- {
- JPakeParameters params;
- JPakeUser alice, bob;
-
- alice.p.name = "Alice";
- alice.p.base = 1;
- bob.p.name = "Bob";
- bob.p.base = 3;
-
- JPakeParametersInit(&params);
-
- // Shared secret
- alice.secret = BN_new();
- BN_rand(alice.secret, 32, -1, 0);
- bob.secret = alice.secret;
- showbn("secret", alice.secret);
-
- assert(BN_cmp(alice.secret, params.q) < 0);
-
- // Alice's x1, x2
- genrand(&alice, &params);
-
- // Bob's x3, x4
- genrand(&bob, &params);
-
- // Now send stuff to each other...
- sendstep1(&alice, &bob.p, &params);
- sendstep1(&bob, &alice.p, &params);
-
- // And verify what each other sent
- if(!verifystep1(&alice, &bob.p, &params))
- return 1;
- if(!verifystep1(&bob, &alice.p, &params))
- return 2;
-
- // Second send
- sendstep2(&alice, &bob.p, &params);
- sendstep2(&bob, &alice.p, &params);
-
- // And second verify
- if(!verifystep2(&alice, &bob.p, &params))
- return 3;
- if(!verifystep2(&bob, &alice.p, &params))
- return 4;
-
- // Compute common key
- computekey(&alice, &params);
- computekey(&bob, &params);
-
- // Confirm the common key is identical
- // XXX: if the two secrets are not the same, everything works up
- // to this point, so the only way to detect a failure is by the
- // difference in the calculated keys.
- // Since we're all the same code, just compare them directly. In a
- // real system, Alice sends Bob H(H(K)), Bob checks it, then sends
- // back H(K), which Alice checks, or something equivalent.
- puts("\nAlice and Bob check keys are the same:");
- if(BN_cmp(alice.key, bob.key) == 0)
- puts(" OK");
- else
- {
- puts(" FAIL");
- return 5;
- }
-
- return 0;
- }
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