diff options
| -rw-r--r-- | acconfig.h | 6 | ||||
| -rw-r--r-- | cipher/rsa.c | 37 | ||||
| -rw-r--r-- | configure.in | 9 | ||||
| -rw-r--r-- | mpi/mpi-add.c | 49 | ||||
| -rw-r--r-- | mpi/mpi-bit.c | 21 | ||||
| -rw-r--r-- | mpi/mpi-inv.c | 152 | ||||
| -rw-r--r-- | mpi/mpiutil.c | 5 |
7 files changed, 180 insertions, 99 deletions
@@ -22,10 +22,14 @@ @@TOP@@ - #undef M_DEBUG #undef VERSION #undef PACKAGE +/* RSA is only compiled in if you have these files. You can use + * RSA with out any restrictions, if your not in the U.S. or + * wait until sep 20, 2000 + */ +#undef HAVE_RSA_CIPHER @@BOTTOM@@ diff --git a/cipher/rsa.c b/cipher/rsa.c index ec761a95..b2694ed5 100644 --- a/cipher/rsa.c +++ b/cipher/rsa.c @@ -91,50 +91,57 @@ rsa_generate( RSA_public_key *pk, RSA_secret_key *sk, unsigned nbits ) MPI n; /* the public key */ MPI e; /* the exponent */ MPI phi; /* helper: (p-a)(q-1) */ + MPI g; + MPI f; /* select two (very secret) primes */ p = generate_random_prime( nbits / 2 ); q = generate_random_prime( nbits / 2 ); - if( mpi_cmp( p, q ) > 0 ) /* p shall be smaller than q */ + if( mpi_cmp( p, q ) > 0 ) /* p shall be smaller than q (for calc of u)*/ mpi_swap(p,q); - /* calculate phi = (p-1)(q-1) */ + /* calculate Euler totient: phi = (p-1)(q-1) */ t1 = mpi_alloc_secure( mpi_get_nlimbs(p) ); t2 = mpi_alloc_secure( mpi_get_nlimbs(p) ); phi = mpi_alloc_secure( nbits / BITS_PER_MPI_LIMB ); + g = mpi_alloc_secure( nbits / BITS_PER_MPI_LIMB ); + f = mpi_alloc_secure( nbits / BITS_PER_MPI_LIMB ); mpi_sub_ui( t1, p, 1 ); mpi_sub_ui( t2, q, 1 ); mpi_mul( phi, t1, t2 ); + mpi_gcd(g, t1, t2); + mpi_fdiv_q(f, phi, g); /* multiply them to make the private key */ n = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); mpi_mul( n, p, q ); /* find a public exponent */ e = mpi_alloc(1); mpi_set_ui( e, 17); /* start with 17 */ - while( !mpi_gcd(t1, e, phi) ) { /* (while gcd is not 1) */ - if( DBG_CIPHER ) - log_mpidump("trying e=", e); + while( !mpi_gcd(t1, e, phi) ) /* (while gcd is not 1) */ mpi_add_ui( e, e, 2); - } /* calculate the secret key d = e^1 mod phi */ d = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); - mpi_inv_mod(d, e, phi ); + mpi_inv_mod(d, e, f ); /* calculate the inverse of p and q (used for chinese remainder theorem)*/ u = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); mpi_inv_mod(u, p, q ); if( DBG_CIPHER ) { - log_mpidump("p=", p ); - log_mpidump("q=", q ); - log_mpidump("phi=", phi ); - log_mpidump("n=", n ); - log_mpidump("e=", e ); - log_mpidump("d=", d ); - log_mpidump("u=", u ); + log_mpidump(" p= ", p ); + log_mpidump(" q= ", q ); + log_mpidump("phi= ", phi ); + log_mpidump(" g= ", g ); + log_mpidump(" f= ", f ); + log_mpidump(" n= ", n ); + log_mpidump(" e= ", e ); + log_mpidump(" d= ", d ); + log_mpidump(" u= ", u ); } mpi_free(t1); mpi_free(t2); mpi_free(phi); + mpi_free(f); + mpi_free(g); pk->n = mpi_copy(n); pk->e = mpi_copy(e); @@ -146,7 +153,7 @@ rsa_generate( RSA_public_key *pk, RSA_secret_key *sk, unsigned nbits ) sk->u = u; /* now we can test our keys (this should never fail!) */ - test_keys( pk, sk, nbits - 16 ); + test_keys( pk, sk, nbits - 64 ); } diff --git a/configure.in b/configure.in index d6eeab10..f6c9f6a1 100644 --- a/configure.in +++ b/configure.in @@ -47,6 +47,15 @@ dnl Checks for library functions. AC_FUNC_VPRINTF AC_CHECK_FUNCS(strerror strtol strtoul) +dnl +AC_MSG_CHECKING(wether we have the rsa source) +if test -f cipher/rsa.c && test -f cipher/rsa.h; then + AC_DEFINE(HAVE_RSA_CIPHER) + AC_MSG_RESULT(yes) +else + AC_MSG_RESULT(no) +fi + AC_OUTPUT([ Makefile util/Makefile mpi/Makefile cipher/Makefile \ g10/Makefile tools/Makefile ], [echo timestamp > stamp-h ]) diff --git a/mpi/mpi-add.c b/mpi/mpi-add.c index 047a2fa3..2c1aa6c6 100644 --- a/mpi/mpi-add.c +++ b/mpi/mpi-add.c @@ -68,7 +68,7 @@ mpi_add_ui(MPI w, MPI u, unsigned long v ) else { mpihelp_sub_1(wp, up, usize, v); /* Size can decrease with at most one limb. */ - wsize = (usize - (wp[usize-1]? 0:1)); + wsize = usize - (wp[usize-1]==0); wsign = 1; } } @@ -85,27 +85,30 @@ mpi_add(MPI w, MPI u, MPI v) mpi_size_t usize, vsize, wsize; int usign, vsign, wsign; - usize = u->nlimbs; - vsize = v->nlimbs; - usign = u->sign; - vsign = v->sign; - - if( usize < vsize ) { /* Swap U and V. */ - { MPI t; t = u; u = v; v = t; } - { mpi_size_t t = usize; usize = vsize; vsize = t; } - { int t = usign; usign = vsign; vsign = t; } + if( u->nlimbs < v->nlimbs ) { /* Swap U and V. */ + usize = v->nlimbs; + usign = v->sign; + vsize = u->nlimbs; + vsign = u->sign; + wsize = usize + 1; + RESIZE_IF_NEEDED(w, wsize); + /* These must be after realloc (u or v may be the same as w). */ + up = v->d; + vp = u->d; + } + else { + usize = u->nlimbs; + usign = u->sign; + vsize = v->nlimbs; + vsign = v->sign; + wsize = usize + 1; + RESIZE_IF_NEEDED(w, wsize); + /* These must be after realloc (u or v may be the same as w). */ + up = u->d; + vp = v->d; } - - /* If not space for w (and possible carry), increase space. */ - wsize = usize + 1; - if( w->alloced < wsize ) - mpi_resize(w, wsize); - wsign = 0; - - /* These must be after realloc (u or v may be the same as w). */ - up = u->d; - vp = v->d; wp = w->d; + wsign = 0; if( !vsize ) { /* simple */ MPN_COPY(wp, up, usize ); @@ -140,7 +143,7 @@ mpi_add(MPI w, MPI u, MPI v) wp[usize] = cy; wsize = usize + cy; if( usign ) - wsize = 1; + wsign = 1; } w->nlimbs = wsize; @@ -193,7 +196,7 @@ mpi_sub_ui(MPI w, MPI u, unsigned long v ) else { mpihelp_sub_1(wp, up, usize, v); /* Size can decrease with at most one limb. */ - wsize = (usize - (wp[usize-1]? 1:0)); + wsize = usize - (wp[usize-1]==0); } } @@ -204,7 +207,7 @@ mpi_sub_ui(MPI w, MPI u, unsigned long v ) void mpi_sub(MPI w, MPI u, MPI v) { - if( w == v ) { + if( 1 || w == v ) { MPI vv = mpi_copy(v); vv->sign = !vv->sign; mpi_add( w, u, vv ); diff --git a/mpi/mpi-bit.c b/mpi/mpi-bit.c index 9cb346aa..9bde9f0f 100644 --- a/mpi/mpi-bit.c +++ b/mpi/mpi-bit.c @@ -130,4 +130,25 @@ mpi_set_bytes( MPI a, unsigned nbits, byte (*fnc)(int), int opaque ) assert(!xbits); } +/**************** + * Shift A by N bits to the right + * FIXME: should use alloc_limb if X and A are same. + */ +void +mpi_rshift( MPI x, MPI a, unsigned n ) +{ + mpi_ptr_t xp; + mpi_size_t xsize; + + xsize = a->nlimbs; + x->sign = a->sign; + RESIZE_IF_NEEDED(x, xsize); + xp = x->d; + + if( xsize ) { + mpihelp_rshift( xp, a->d, xsize, n); + MPN_NORMALIZE( xp, xsize); + } + x->nlimbs = xsize; +} diff --git a/mpi/mpi-inv.c b/mpi/mpi-inv.c index acde6055..f37f4e51 100644 --- a/mpi/mpi-inv.c +++ b/mpi/mpi-inv.c @@ -23,20 +23,21 @@ #include <stdlib.h> #include "mpi-internal.h" + /**************** - * Calculate the multiplicative inverse X of U mod V - * That is: Find the solution for - * 1 = (u*x) mod v - * This has only a unique solution if U and V are relatively prime. - * Returns 0 if a solution was found. + * Calculate the multiplicative inverse X of A mod N + * That is: Find the solution x for + * 1 = (a*x) mod n */ -int -mpi_inv_mod( MPI x, MPI u, MPI v ) +void +mpi_inv_mod( MPI x, MPI a, MPI n ) { #if 0 - /* Extended Euclid's algorithm (See TAOPC Vol II, 4.52. Alg X) */ - MPI u1, u2, u3, v1, v2, v3, q, t1, t2, t3; + MPI u, v, u1, u2, u3, v1, v2, v3, q, t1, t2, t3; + MPI ta, tb, tc; + u = mpi_copy(a); + v = mpi_copy(n); u1 = mpi_alloc_set_ui(1); u2 = mpi_alloc_set_ui(0); u3 = mpi_copy(u); @@ -48,22 +49,20 @@ mpi_inv_mod( MPI x, MPI u, MPI v ) t2 = mpi_alloc( mpi_get_nlimbs(u) ); t3 = mpi_alloc( mpi_get_nlimbs(u) ); while( mpi_cmp_ui( v3, 0 ) ) { - /*log_debug("----------------------\n"); - log_mpidump("q =", u1); - log_mpidump("u1=", u1); - log_mpidump("u2=", u2); - log_mpidump("u3=", u3); - log_mpidump("v1=", v1); - log_mpidump("v2=", v2); - log_mpidump("v3=", v3); */ mpi_fdiv_q( q, u3, v3 ); mpi_mul(t1, v1, q); mpi_mul(t2, v2, q); mpi_mul(t3, v3, q); mpi_sub(t1, u1, t1); mpi_sub(t2, u2, t2); mpi_sub(t3, u3, t3); - mpi_set(u1, v1); mpi_set(u2, v2); mpi_set(u3, v3); mpi_set(v1, t1); mpi_set(v2, t2); mpi_set(v3, t3); } - mpi_set(x, u3); + /* log_debug("result:\n"); + log_mpidump("q =", q ); + log_mpidump("u1=", u1); + log_mpidump("u2=", u2); + log_mpidump("u3=", u3); + log_mpidump("v1=", v1); + log_mpidump("v2=", v2); */ + mpi_set(x, u1); mpi_free(u1); mpi_free(u2); @@ -75,52 +74,89 @@ mpi_inv_mod( MPI x, MPI u, MPI v ) mpi_free(t1); mpi_free(t2); mpi_free(t3); - #endif + mpi_free(u); + mpi_free(v); + #else + /* Extended Euclid's algorithm (See TAOPC Vol II, 4.5.2, Alg X) + * modified according to Michael Penk's solution for Exercice 35 */ - /***************************** - * 1. Init: g0 = u g1 = v v0 = 0 v1 = 1 - * 2. Test: if g1 is 0 terminate. Result = v0 < 0: v0 + n - * else: v0 - * 3. Divide: div,rem = g0 / g1 - * t1 = v0 - div * v1 - * v0 = v1 - * v1 = t1 - * g0 = g1 - * g1 = rem - * continue with step 2. - */ - MPI g0, g1, v0, v1, div, rem, t1; + /* FIXME: we can simplify this in most cases (see Knuth) */ + MPI u, v, u1, u2, u3, v1, v2, v3, t1, t2, t3; + unsigned k; + int sign; + + u = mpi_copy(a); + v = mpi_copy(n); + for(k=0; !mpi_test_bit(u,0) && !mpi_test_bit(v,0); k++ ) { + mpi_rshift(u, u, 1); + mpi_rshift(v, v, 1); + } - g0 = mpi_copy(v); - g1 = mpi_copy(u); - v0 = mpi_alloc_set_ui( 0 ); - v1 = mpi_alloc_set_ui( 1 ); - div = mpi_alloc(mpi_get_nlimbs(v)); - rem = mpi_alloc(mpi_get_nlimbs(v)); - t1 = mpi_alloc(mpi_get_nlimbs(v)); - while( mpi_cmp_ui( g1, 0) ) { - mpi_fdiv_qr(div, rem, g0, g1); - mpi_mul(t1, div, v1); - mpi_sub(t1, v0, t1); - mpi_set(v0, v1); - mpi_set(v1, t1); - mpi_set(g0, g1); - mpi_set(g1, rem); + u1 = mpi_alloc_set_ui(1); + u2 = mpi_alloc_set_ui(0); + u3 = mpi_copy(u); + v1 = mpi_copy(v); /* !-- used as const 1 */ + v2 = mpi_alloc( mpi_get_nlimbs(u) ); mpi_sub( v2, u1, u ); + v3 = mpi_copy(v); + if( mpi_test_bit(u, 0) ) { /* u is odd */ + t1 = mpi_alloc_set_ui(0); + t2 = mpi_alloc_set_ui(1); t2->sign = 1; + t3 = mpi_copy(v); t3->sign = !t3->sign; + goto Y4; + } + else { + t1 = mpi_alloc_set_ui(1); + t2 = mpi_alloc_set_ui(0); + t3 = mpi_copy(u); } - if( mpi_cmp_ui( v0, 0) < 0 ) - mpi_add( x, v0, v); - else - mpi_set( x, v0); + do { + do { + if( mpi_test_bit(t1, 0) || mpi_test_bit(t2, 0) ) { /* one is odd */ + mpi_add(t1, t1, v); + mpi_sub(t2, t2, u); + } + mpi_rshift(t1, t1, 1); + mpi_rshift(t2, t2, 1); + mpi_rshift(t3, t3, 1); + Y4: + } while( !mpi_test_bit( t3, 0 ) ); /* while t3 is even */ - mpi_free(g0); - mpi_free(g1); - mpi_free(v0); + if( !t3->sign ) { + mpi_set(u1, t1); + mpi_set(u2, t2); + mpi_set(u3, t3); + } + else { + mpi_sub(v1, v, t1); + sign = u->sign; u->sign = !u->sign; + mpi_sub(v2, u, t2); + u->sign = sign; + sign = t3->sign; t3->sign = !t3->sign; + mpi_set(v3, t3); + t3->sign = sign; + } + mpi_sub(t1, u1, v1); + mpi_sub(t2, u2, v2); + mpi_sub(t3, u3, v3); + if( t1->sign ) { + mpi_add(t1, t1, v); + mpi_sub(t2, t2, u); + } + } while( mpi_cmp_ui( t3, 0 ) ); /* while t3 != 0 */ + /* mpi_lshift( u3, k ); */ + mpi_set(x, u1); + + mpi_free(u1); + mpi_free(u2); + mpi_free(u3); mpi_free(v1); - mpi_free(div); - mpi_free(rem); + mpi_free(v2); + mpi_free(v3); mpi_free(t1); - return 0; + mpi_free(t2); + mpi_free(t3); + #endif } diff --git a/mpi/mpiutil.c b/mpi/mpiutil.c index 752ce7f8..4e2a0905 100644 --- a/mpi/mpiutil.c +++ b/mpi/mpiutil.c @@ -265,6 +265,7 @@ mpi_copy( MPI a ) b = mpi_alloc( a->nlimbs ); #endif b->nlimbs = a->nlimbs; + b->sign = a->sign; for(i=0; i < b->nlimbs; i++ ) b->d[i] = a->d[i]; } @@ -318,9 +319,9 @@ mpi_alloc_set_ui( unsigned long u) void mpi_swap( MPI a, MPI b) { - MPI x; + struct mpi_struct tmp; - x = a; a = b; b = x; + tmp = *a; *a = *b; *b = tmp; } |