diff options
Diffstat (limited to 'lib/mpi')
| -rw-r--r-- | lib/mpi/Makefile | 11 | ||||
| -rw-r--r-- | lib/mpi/generic_mpi-asm-defs.h | 4 | ||||
| -rw-r--r-- | lib/mpi/mpi-add.c | 234 | ||||
| -rw-r--r-- | lib/mpi/mpi-cmp.c | 68 | ||||
| -rw-r--r-- | lib/mpi/mpi-div.c | 333 | ||||
| -rw-r--r-- | lib/mpi/mpi-gcd.c | 59 | ||||
| -rw-r--r-- | lib/mpi/mpi-inline.c | 31 | ||||
| -rw-r--r-- | lib/mpi/mpi-inv.c | 187 | ||||
| -rw-r--r-- | lib/mpi/mpi-mpow.c | 133 | ||||
| -rw-r--r-- | lib/mpi/mpi-mul.c | 194 | ||||
| -rw-r--r-- | lib/mpi/mpi-scan.c | 136 |
11 files changed, 1390 insertions, 0 deletions
diff --git a/lib/mpi/Makefile b/lib/mpi/Makefile index 45ca90a8639c..567d52e74d77 100644 --- a/lib/mpi/Makefile +++ b/lib/mpi/Makefile @@ -19,3 +19,14 @@ mpi-y = \ mpih-mul.o \ mpi-pow.o \ mpiutil.o + +mpi-$(CONFIG_MPILIB_EXTRA) += \ + mpi-add.o \ + mpi-div.o \ + mpi-cmp.o \ + mpi-gcd.o \ + mpi-inline.o \ + mpi-inv.o \ + mpi-mpow.o \ + mpi-mul.o \ + mpi-scan.o diff --git a/lib/mpi/generic_mpi-asm-defs.h b/lib/mpi/generic_mpi-asm-defs.h new file mode 100644 index 000000000000..047d1f5a7249 --- /dev/null +++ b/lib/mpi/generic_mpi-asm-defs.h @@ -0,0 +1,4 @@ +/* This file defines some basic constants for the MPI machinery. We + * need to define the types on a per-CPU basis, so it is done with + * this file here. */ +#define BYTES_PER_MPI_LIMB (SIZEOF_UNSIGNED_LONG) diff --git a/lib/mpi/mpi-add.c b/lib/mpi/mpi-add.c new file mode 100644 index 000000000000..f56b9ba295e6 --- /dev/null +++ b/lib/mpi/mpi-add.c @@ -0,0 +1,234 @@ +/* mpi-add.c - MPI functions + * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * Copyright (C) 1994, 1996 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + * The GNU MP Library itself is published under the LGPL; + * however I decided to publish this code under the plain GPL. + */ + +#include "mpi-internal.h" + +/**************** + * Add the unsigned integer V to the mpi-integer U and store the + * result in W. U and V may be the same. + */ +int mpi_add_ui(MPI w, const MPI u, unsigned long v) +{ + mpi_ptr_t wp, up; + mpi_size_t usize, wsize; + int usign, wsign; + + usize = u->nlimbs; + usign = u->sign; + wsign = 0; + + /* If not space for W (and possible carry), increase space. */ + wsize = usize + 1; + if (w->alloced < wsize) + if (mpi_resize(w, wsize) < 0) + return -ENOMEM; + + /* These must be after realloc (U may be the same as W). */ + up = u->d; + wp = w->d; + + if (!usize) { /* simple */ + wp[0] = v; + wsize = v ? 1 : 0; + } else if (!usign) { /* mpi is not negative */ + mpi_limb_t cy; + cy = mpihelp_add_1(wp, up, usize, v); + wp[usize] = cy; + wsize = usize + cy; + } else { /* The signs are different. Need exact comparison to determine + * which operand to subtract from which. */ + if (usize == 1 && up[0] < v) { + wp[0] = v - up[0]; + wsize = 1; + } else { + mpihelp_sub_1(wp, up, usize, v); + /* Size can decrease with at most one limb. */ + wsize = usize - (wp[usize - 1] == 0); + wsign = 1; + } + } + + w->nlimbs = wsize; + w->sign = wsign; + return 0; +} + +int mpi_add(MPI w, MPI u, MPI v) +{ + mpi_ptr_t wp, up, vp; + mpi_size_t usize, vsize, wsize; + int usign, vsign, wsign; + + if (u->nlimbs < v->nlimbs) { /* Swap U and V. */ + usize = v->nlimbs; + usign = v->sign; + vsize = u->nlimbs; + vsign = u->sign; + wsize = usize + 1; + if (RESIZE_IF_NEEDED(w, wsize) < 0) + return -ENOMEM; + /* 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; + if (RESIZE_IF_NEEDED(w, wsize) < 0) + return -ENOMEM; + /* 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); + wsize = usize; + wsign = usign; + } else if (usign != vsign) { /* different sign */ + /* This test is right since USIZE >= VSIZE */ + if (usize != vsize) { + mpihelp_sub(wp, up, usize, vp, vsize); + wsize = usize; + MPN_NORMALIZE(wp, wsize); + wsign = usign; + } else if (mpihelp_cmp(up, vp, usize) < 0) { + mpihelp_sub_n(wp, vp, up, usize); + wsize = usize; + MPN_NORMALIZE(wp, wsize); + if (!usign) + wsign = 1; + } else { + mpihelp_sub_n(wp, up, vp, usize); + wsize = usize; + MPN_NORMALIZE(wp, wsize); + if (usign) + wsign = 1; + } + } else { /* U and V have same sign. Add them. */ + mpi_limb_t cy = mpihelp_add(wp, up, usize, vp, vsize); + wp[usize] = cy; + wsize = usize + cy; + if (usign) + wsign = 1; + } + + w->nlimbs = wsize; + w->sign = wsign; + return 0; +} + +/**************** + * Subtract the unsigned integer V from the mpi-integer U and store the + * result in W. + */ +int mpi_sub_ui(MPI w, MPI u, unsigned long v) +{ + mpi_ptr_t wp, up; + mpi_size_t usize, wsize; + int usign, wsign; + + usize = u->nlimbs; + usign = u->sign; + wsign = 0; + + /* If not space for W (and possible carry), increase space. */ + wsize = usize + 1; + if (w->alloced < wsize) + if (mpi_resize(w, wsize) < 0) + return -ENOMEM; + + /* These must be after realloc (U may be the same as W). */ + up = u->d; + wp = w->d; + + if (!usize) { /* simple */ + wp[0] = v; + wsize = v ? 1 : 0; + wsign = 1; + } else if (usign) { /* mpi and v are negative */ + mpi_limb_t cy; + cy = mpihelp_add_1(wp, up, usize, v); + wp[usize] = cy; + wsize = usize + cy; + } else { /* The signs are different. Need exact comparison to determine + * which operand to subtract from which. */ + if (usize == 1 && up[0] < v) { + wp[0] = v - up[0]; + wsize = 1; + wsign = 1; + } else { + mpihelp_sub_1(wp, up, usize, v); + /* Size can decrease with at most one limb. */ + wsize = usize - (wp[usize - 1] == 0); + } + } + + w->nlimbs = wsize; + w->sign = wsign; + return 0; +} + +int mpi_sub(MPI w, MPI u, MPI v) +{ + int rc; + + if (w == v) { + MPI vv; + if (mpi_copy(&vv, v) < 0) + return -ENOMEM; + vv->sign = !vv->sign; + rc = mpi_add(w, u, vv); + mpi_free(vv); + } else { + /* fixme: this is not thread-save (we temp. modify v) */ + v->sign = !v->sign; + rc = mpi_add(w, u, v); + v->sign = !v->sign; + } + return rc; +} + +int mpi_addm(MPI w, MPI u, MPI v, MPI m) +{ + if (mpi_add(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0) + return -ENOMEM; + return 0; +} + +int mpi_subm(MPI w, MPI u, MPI v, MPI m) +{ + if (mpi_sub(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0) + return -ENOMEM; + return 0; +} diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c new file mode 100644 index 000000000000..914bc42a8a80 --- /dev/null +++ b/lib/mpi/mpi-cmp.c @@ -0,0 +1,68 @@ +/* mpi-cmp.c - MPI functions + * Copyright (C) 1998, 1999 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "mpi-internal.h" + +int mpi_cmp_ui(MPI u, unsigned long v) +{ + mpi_limb_t limb = v; + + mpi_normalize(u); + if (!u->nlimbs && !limb) + return 0; + if (u->sign) + return -1; + if (u->nlimbs > 1) + return 1; + + if (u->d[0] == limb) + return 0; + else if (u->d[0] > limb) + return 1; + else + return -1; +} + +int mpi_cmp(MPI u, MPI v) +{ + mpi_size_t usize, vsize; + int cmp; + + mpi_normalize(u); + mpi_normalize(v); + usize = u->nlimbs; + vsize = v->nlimbs; + if (!u->sign && v->sign) + return 1; + if (u->sign && !v->sign) + return -1; + if (usize != vsize && !u->sign && !v->sign) + return usize - vsize; + if (usize != vsize && u->sign && v->sign) + return vsize + usize; + if (!usize) + return 0; + cmp = mpihelp_cmp(u->d, v->d, usize); + if (!cmp) + return 0; + if ((cmp < 0 ? 1 : 0) == (u->sign ? 1 : 0)) + return 1; + return -1; +} diff --git a/lib/mpi/mpi-div.c b/lib/mpi/mpi-div.c new file mode 100644 index 000000000000..c3087d1390ce --- /dev/null +++ b/lib/mpi/mpi-div.c @@ -0,0 +1,333 @@ +/* mpi-div.c - MPI functions + * Copyright (C) 1994, 1996 Free Software Foundation, Inc. + * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + * The GNU MP Library itself is published under the LGPL; + * however I decided to publish this code under the plain GPL. + */ + +#include <linux/string.h> +#include "mpi-internal.h" +#include "longlong.h" + +int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor) +{ + int rc = -ENOMEM; + int divisor_sign = divisor->sign; + MPI temp_divisor = NULL; + + /* We need the original value of the divisor after the remainder has been + * preliminary calculated. We have to copy it to temporary space if it's + * the same variable as REM. */ + if (rem == divisor) { + if (mpi_copy(&temp_divisor, divisor) < 0) + goto nomem; + divisor = temp_divisor; + } + + if (mpi_tdiv_qr(NULL, rem, dividend, divisor) < 0) + goto nomem; + if (((divisor_sign ? 1 : 0) ^ (dividend->sign ? 1 : 0)) && rem->nlimbs) + if (mpi_add(rem, rem, divisor) < 0) + goto nomem; + + rc = 0; + +nomem: + if (temp_divisor) + mpi_free(temp_divisor); + return rc; +} + +/**************** + * Division rounding the quotient towards -infinity. + * The remainder gets the same sign as the denominator. + * rem is optional + */ + +ulong mpi_fdiv_r_ui(MPI rem, MPI dividend, ulong divisor) +{ + mpi_limb_t rlimb; + + rlimb = mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor); + if (rlimb && dividend->sign) + rlimb = divisor - rlimb; + + if (rem) { + rem->d[0] = rlimb; + rem->nlimbs = rlimb ? 1 : 0; + } + return rlimb; +} + +int mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor) +{ + MPI tmp = mpi_alloc(mpi_get_nlimbs(quot)); + if (!tmp) + return -ENOMEM; + mpi_fdiv_qr(quot, tmp, dividend, divisor); + mpi_free(tmp); + return 0; +} + +int mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor) +{ + int divisor_sign = divisor->sign; + MPI temp_divisor = NULL; + + if (quot == divisor || rem == divisor) { + if (mpi_copy(&temp_divisor, divisor) < 0) + return -ENOMEM; + divisor = temp_divisor; + } + + if (mpi_tdiv_qr(quot, rem, dividend, divisor) < 0) + goto nomem; + + if ((divisor_sign ^ dividend->sign) && rem->nlimbs) { + if (mpi_sub_ui(quot, quot, 1) < 0) + goto nomem; + if (mpi_add(rem, rem, divisor) < 0) + goto nomem; + } + + if (temp_divisor) + mpi_free(temp_divisor); + + return 0; + +nomem: + mpi_free(temp_divisor); + return -ENOMEM; +} + +/* If den == quot, den needs temporary storage. + * If den == rem, den needs temporary storage. + * If num == quot, num needs temporary storage. + * If den has temporary storage, it can be normalized while being copied, + * i.e no extra storage should be allocated. + */ + +int mpi_tdiv_r(MPI rem, MPI num, MPI den) +{ + return mpi_tdiv_qr(NULL, rem, num, den); +} + +int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) +{ + int rc = -ENOMEM; + mpi_ptr_t np, dp; + mpi_ptr_t qp, rp; + mpi_size_t nsize = num->nlimbs; + mpi_size_t dsize = den->nlimbs; + mpi_size_t qsize, rsize; + mpi_size_t sign_remainder = num->sign; + mpi_size_t sign_quotient = num->sign ^ den->sign; + unsigned normalization_steps; + mpi_limb_t q_limb; + mpi_ptr_t marker[5]; + int markidx = 0; + + memset(marker, 0, sizeof(marker)); + + /* Ensure space is enough for quotient and remainder. + * We need space for an extra limb in the remainder, because it's + * up-shifted (normalized) below. */ + rsize = nsize + 1; + if (mpi_resize(rem, rsize) < 0) + goto nomem; + + qsize = rsize - dsize; /* qsize cannot be bigger than this. */ + if (qsize <= 0) { + if (num != rem) { + rem->nlimbs = num->nlimbs; + rem->sign = num->sign; + MPN_COPY(rem->d, num->d, nsize); + } + if (quot) { + /* This needs to follow the assignment to rem, in case the + * numerator and quotient are the same. */ + quot->nlimbs = 0; + quot->sign = 0; + } + return 0; + } + + if (quot) + if (mpi_resize(quot, qsize) < 0) + goto nomem; + + /* Read pointers here, when reallocation is finished. */ + np = num->d; + dp = den->d; + rp = rem->d; + + /* Optimize division by a single-limb divisor. */ + if (dsize == 1) { + mpi_limb_t rlimb; + if (quot) { + qp = quot->d; + rlimb = mpihelp_divmod_1(qp, np, nsize, dp[0]); + qsize -= qp[qsize - 1] == 0; + quot->nlimbs = qsize; + quot->sign = sign_quotient; + } else + rlimb = mpihelp_mod_1(np, nsize, dp[0]); + rp[0] = rlimb; + rsize = rlimb != 0 ? 1 : 0; + rem->nlimbs = rsize; + rem->sign = sign_remainder; + return 0; + } + + if (quot) { + qp = quot->d; + /* Make sure QP and NP point to different objects. Otherwise the + * numerator would be gradually overwritten by the quotient limbs. */ + if (qp == np) { /* Copy NP object to temporary space. */ + np = marker[markidx++] = mpi_alloc_limb_space(nsize); + MPN_COPY(np, qp, nsize); + } + } else /* Put quotient at top of remainder. */ + qp = rp + dsize; + + count_leading_zeros(normalization_steps, dp[dsize - 1]); + + /* Normalize the denominator, i.e. make its most significant bit set by + * shifting it NORMALIZATION_STEPS bits to the left. Also shift the + * numerator the same number of steps (to keep the quotient the same!). + */ + if (normalization_steps) { + mpi_ptr_t tp; + mpi_limb_t nlimb; + + /* Shift up the denominator setting the most significant bit of + * the most significant word. Use temporary storage not to clobber + * the original contents of the denominator. */ + tp = marker[markidx++] = mpi_alloc_limb_space(dsize); + if (!tp) + goto nomem; + mpihelp_lshift(tp, dp, dsize, normalization_steps); + dp = tp; + + /* Shift up the numerator, possibly introducing a new most + * significant word. Move the shifted numerator in the remainder + * meanwhile. */ + nlimb = mpihelp_lshift(rp, np, nsize, normalization_steps); + if (nlimb) { + rp[nsize] = nlimb; + rsize = nsize + 1; + } else + rsize = nsize; + } else { + /* The denominator is already normalized, as required. Copy it to + * temporary space if it overlaps with the quotient or remainder. */ + if (dp == rp || (quot && (dp == qp))) { + mpi_ptr_t tp; + + tp = marker[markidx++] = mpi_alloc_limb_space(dsize); + if (!tp) + goto nomem; + MPN_COPY(tp, dp, dsize); + dp = tp; + } + + /* Move the numerator to the remainder. */ + if (rp != np) + MPN_COPY(rp, np, nsize); + + rsize = nsize; + } + + q_limb = mpihelp_divrem(qp, 0, rp, rsize, dp, dsize); + + if (quot) { + qsize = rsize - dsize; + if (q_limb) { + qp[qsize] = q_limb; + qsize += 1; + } + + quot->nlimbs = qsize; + quot->sign = sign_quotient; + } + + rsize = dsize; + MPN_NORMALIZE(rp, rsize); + + if (normalization_steps && rsize) { + mpihelp_rshift(rp, rp, rsize, normalization_steps); + rsize -= rp[rsize - 1] == 0 ? 1 : 0; + } + + rem->nlimbs = rsize; + rem->sign = sign_remainder; + + rc = 0; +nomem: + while (markidx) + mpi_free_limb_space(marker[--markidx]); + return rc; +} + +int mpi_tdiv_q_2exp(MPI w, MPI u, unsigned count) +{ + mpi_size_t usize, wsize; + mpi_size_t limb_cnt; + + usize = u->nlimbs; + limb_cnt = count / BITS_PER_MPI_LIMB; + wsize = usize - limb_cnt; + if (limb_cnt >= usize) + w->nlimbs = 0; + else { + mpi_ptr_t wp; + mpi_ptr_t up; + + if (RESIZE_IF_NEEDED(w, wsize) < 0) + return -ENOMEM; + wp = w->d; + up = u->d; + + count %= BITS_PER_MPI_LIMB; + if (count) { + mpihelp_rshift(wp, up + limb_cnt, wsize, count); + wsize -= !wp[wsize - 1]; + } else { + MPN_COPY_INCR(wp, up + limb_cnt, wsize); + } + + w->nlimbs = wsize; + } + return 0; +} + +/**************** + * Check whether dividend is divisible by divisor + * (note: divisor must fit into a limb) + */ +int mpi_divisible_ui(MPI dividend, ulong divisor) +{ + return !mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor); +} diff --git a/lib/mpi/mpi-gcd.c b/lib/mpi/mpi-gcd.c new file mode 100644 index 000000000000..13c48aef9c4e --- /dev/null +++ b/lib/mpi/mpi-gcd.c @@ -0,0 +1,59 @@ +/* mpi-gcd.c - MPI functions + * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "mpi-internal.h" + +/**************** + * Find the greatest common divisor G of A and B. + * Return: true if this 1, false in all other cases + */ +int mpi_gcd(MPI g, const MPI xa, const MPI xb) +{ + MPI a = NULL, b = NULL; + + if (mpi_copy(&a, xa) < 0) + goto nomem; + + if (mpi_copy(&b, xb) < 0) + goto nomem; + + /* TAOCP Vol II, 4.5.2, Algorithm A */ + a->sign = 0; + b->sign = 0; + while (mpi_cmp_ui(b, 0)) { + if (mpi_fdiv_r(g, a, b) < 0) /* g used as temorary variable */ + goto nomem; + if (mpi_set(a, b) < 0) + goto nomem; + if (mpi_set(b, g) < 0) + goto nomem; + } + if (mpi_set(g, a) < 0) + goto nomem; + + mpi_free(a); + mpi_free(b); + return !mpi_cmp_ui(g, 1); + +nomem: + mpi_free(a); + mpi_free(b); + return -ENOMEM; +} diff --git a/lib/mpi/mpi-inline.c b/lib/mpi/mpi-inline.c new file mode 100644 index 000000000000..654f68aeed8b --- /dev/null +++ b/lib/mpi/mpi-inline.c @@ -0,0 +1,31 @@ +/* mpi-inline.c + * Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +/* put the inline functions as real functions into the lib */ +#define G10_MPI_INLINE_DECL + +#include "mpi-internal.h" + +/* always include the header becuase it is only + * included by mpi-internal if __GCC__ is defined but we + * need it here in all cases and the above definition of + * of the macro allows us to do so + */ +#include "mpi-inline.h" diff --git a/lib/mpi/mpi-inv.c b/lib/mpi/mpi-inv.c new file mode 100644 index 000000000000..0951f9847745 --- /dev/null +++ b/lib/mpi/mpi-inv.c @@ -0,0 +1,187 @@ +/* mpi-inv.c - MPI functions + * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "mpi-internal.h" + +/**************** + * Calculate the multiplicative inverse X of A mod N + * That is: Find the solution x for + * 1 = (a*x) mod n + */ +int mpi_invm(MPI x, const MPI a, const MPI n) +{ + /* Extended Euclid's algorithm (See TAOPC Vol II, 4.5.2, Alg X) + * modified according to Michael Penk's solution for Exercice 35 + * with further enhancement */ + MPI u = NULL, v = NULL; + MPI u1 = NULL, u2 = NULL, u3 = NULL; + MPI v1 = NULL, v2 = NULL, v3 = NULL; + MPI t1 = NULL, t2 = NULL, t3 = NULL; + unsigned k; + int sign; + int odd = 0; + int rc = -ENOMEM; + + if (mpi_copy(&u, a) < 0) + goto cleanup; + if (mpi_copy(&v, n) < 0) + goto cleanup; + + for (k = 0; !mpi_test_bit(u, 0) && !mpi_test_bit(v, 0); k++) { + if (mpi_rshift(u, u, 1) < 0) + goto cleanup; + if (mpi_rshift(v, v, 1) < 0) + goto cleanup; + } + odd = mpi_test_bit(v, 0); + + u1 = mpi_alloc_set_ui(1); + if (!u1) + goto cleanup; + if (!odd) { + u2 = mpi_alloc_set_ui(0); + if (!u2) + goto cleanup; + } + if (mpi_copy(&u3, u) < 0) + goto cleanup; + if (mpi_copy(&v1, v) < 0) + goto cleanup; + if (!odd) { + v2 = mpi_alloc(mpi_get_nlimbs(u)); + if (!v2) + goto cleanup; + if (mpi_sub(v2, u1, u) < 0) + goto cleanup; /* U is used as const 1 */ + } + if (mpi_copy(&v3, v) < 0) + goto cleanup; + if (mpi_test_bit(u, 0)) { /* u is odd */ + t1 = mpi_alloc_set_ui(0); + if (!t1) + goto cleanup; + if (!odd) { + t2 = mpi_alloc_set_ui(1); + if (!t2) + goto cleanup; + t2->sign = 1; + } + if (mpi_copy(&t3, v) < 0) + goto cleanup; + t3->sign = !t3->sign; + goto Y4; + } else { + t1 = mpi_alloc_set_ui(1); + if (!t1) + goto cleanup; + if (!odd) { + t2 = mpi_alloc_set_ui(0); + if (!t2) + goto cleanup; + } + if (mpi_copy(&t3, u) < 0) + goto cleanup; + } + do { + do { + if (!odd) { + if (mpi_test_bit(t1, 0) || mpi_test_bit(t2, 0)) { /* one is odd */ + if (mpi_add(t1, t1, v) < 0) + goto cleanup; + if (mpi_sub(t2, t2, u) < 0) + goto cleanup; + } + if (mpi_rshift(t1, t1, 1) < 0) + goto cleanup; + if (mpi_rshift(t2, t2, 1) < 0) + goto cleanup; + if (mpi_rshift(t3, t3, 1) < 0) + goto cleanup; + } else { + if (mpi_test_bit(t1, 0)) + if (mpi_add(t1, t1, v) < 0) + goto cleanup; + if (mpi_rshift(t1, t1, 1) < 0) + goto cleanup; + if (mpi_rshift(t3, t3, 1) < 0) + goto cleanup; + } +Y4: + ; + } while (!mpi_test_bit(t3, 0)); /* while t3 is even */ + + if (!t3->sign) { + if (mpi_set(u1, t1) < 0) + goto cleanup; + if (!odd) + if (mpi_set(u2, t2) < 0) + goto cleanup; + if (mpi_set(u3, t3) < 0) + goto cleanup; + } else { + if (mpi_sub(v1, v, t1) < 0) + goto cleanup; + sign = u->sign; + u->sign = !u->sign; + if (!odd) + if (mpi_sub(v2, u, t2) < 0) + goto cleanup; + u->sign = sign; + sign = t3->sign; + t3->sign = !t3->sign; + if (mpi_set(v3, t3) < 0) + goto cleanup; + t3->sign = sign; + } + if (mpi_sub(t1, u1, v1) < 0) + goto cleanup; + if (!odd) + if (mpi_sub(t2, u2, v2) < 0) + goto cleanup; + if (mpi_sub(t3, u3, v3) < 0) + goto cleanup; + if (t1->sign) { + if (mpi_add(t1, t1, v) < 0) + goto cleanup; + if (!odd) + if (mpi_sub(t2, t2, u) < 0) + goto cleanup; + } + } while (mpi_cmp_ui(t3, 0)); /* while t3 != 0 */ + /* mpi_lshift( u3, k ); */ + rc = mpi_set(x, u1); + +cleanup: + mpi_free(u1); + mpi_free(v1); + mpi_free(t1); + if (!odd) { + mpi_free(u2); + mpi_free(v2); + mpi_free(t2); + } + mpi_free(u3); + mpi_free(v3); + mpi_free(t3); + + mpi_free(u); + mpi_free(v); + return rc; +} diff --git a/lib/mpi/mpi-mpow.c b/lib/mpi/mpi-mpow.c new file mode 100644 index 000000000000..4cc75933c5a7 --- /dev/null +++ b/lib/mpi/mpi-mpow.c @@ -0,0 +1,133 @@ +/* mpi-mpow.c - MPI functions + * Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "mpi-internal.h" +#include "longlong.h" + +static int build_index(const MPI *exparray, int k, int i, int t) +{ + int j, bitno; + int index = 0; + + bitno = t - i; + for (j = k - 1; j >= 0; j--) { + index <<= 1; + if (mpi_test_bit(exparray[j], bitno)) + index |= 1; + } + return index; +} + +/**************** + * RES = (BASE[0] ^ EXP[0]) * (BASE[1] ^ EXP[1]) * ... * mod M + */ +int mpi_mulpowm(MPI res, MPI *basearray, MPI *exparray, MPI m) +{ + int rc = -ENOMEM; + int k; /* number of elements */ + int t; /* bit size of largest exponent */ + int i, j, idx; + MPI *G = NULL; /* table with precomputed values of size 2^k */ + MPI tmp = NULL; + + for (k = 0; basearray[k]; k++) + ; + if (!k) { + pr_emerg("mpi_mulpowm: assert(k) failed\n"); + BUG(); + } + for (t = 0, i = 0; (tmp = exparray[i]); i++) { + j = mpi_get_nbits(tmp); + if (j > t) + t = j; + } + if (i != k) { + pr_emerg("mpi_mulpowm: assert(i==k) failed\n"); + BUG(); + } + if (!t) { + pr_emerg("mpi_mulpowm: assert(t) failed\n"); + BUG(); + } + if (k >= 10) { + pr_emerg("mpi_mulpowm: assert(k<10) failed\n"); + BUG(); + } + + G = kzalloc((1 << k) * sizeof *G, GFP_KERNEL); + if (!G) + goto nomem; + + /* and calculate */ + tmp = mpi_alloc(mpi_get_nlimbs(m) + 1); + if (!tmp) + goto nomem; + if (mpi_set_ui(res, 1) < 0) + goto nomem; + for (i = 1; i <= t; i++) { + if (mpi_mulm(tmp, res, res, m) < 0) + goto nomem; + idx = build_index(exparray, k, i, t); + if (!(idx >= 0 && idx < (1 << k))) { + pr_emerg("mpi_mulpowm: assert(idx >= 0 && idx < (1<<k)) failed\n"); + BUG(); + } + if (!G[idx]) { + if (!idx) { + G[0] = mpi_alloc_set_ui(1); + if (!G[0]) + goto nomem; + } else { + for (j = 0; j < k; j++) { + if ((idx & (1 << j))) { + if (!G[idx]) { + if (mpi_copy + (&G[idx], + basearray[j]) < 0) + goto nomem; + } else { + if (mpi_mulm + (G[idx], G[idx], + basearray[j], + m) < 0) + goto nomem; + } + } + } + if (!G[idx]) { + G[idx] = mpi_alloc(0); + if (!G[idx]) + goto nomem; + } + } + } + if (mpi_mulm(res, tmp, G[idx], m) < 0) + goto nomem; + } + + rc = 0; +nomem: + /* cleanup */ + mpi_free(tmp); + for (i = 0; i < (1 << k); i++) + mpi_free(G[i]); + kfree(G); + return rc; +} diff --git a/lib/mpi/mpi-mul.c b/lib/mpi/mpi-mul.c new file mode 100644 index 000000000000..1f3219e27292 --- /dev/null +++ b/lib/mpi/mpi-mul.c @@ -0,0 +1,194 @@ +/* mpi-mul.c - MPI functions + * Copyright (C) 1994, 1996 Free Software Foundation, Inc. + * Copyright (C) 1998, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + * The GNU MP Library itself is published under the LGPL; + * however I decided to publish this code under the plain GPL. + */ + +#include "mpi-internal.h" + +int mpi_mul_ui(MPI prod, MPI mult, unsigned long small_mult) +{ + mpi_size_t size, prod_size; + mpi_ptr_t prod_ptr; + mpi_limb_t cy; + int sign; + + size = mult->nlimbs; + sign = mult->sign; + + if (!size || !small_mult) { + prod->nlimbs = 0; + prod->sign = 0; + return 0; + } + + prod_size = size + 1; + if (prod->alloced < prod_size) + if (mpi_resize(prod, prod_size) < 0) + return -ENOMEM; + prod_ptr = prod->d; + + cy = mpihelp_mul_1(prod_ptr, mult->d, size, (mpi_limb_t) small_mult); + if (cy) + prod_ptr[size++] = cy; + prod->nlimbs = size; + prod->sign = sign; + return 0; +} + +int mpi_mul_2exp(MPI w, MPI u, unsigned long cnt) +{ + mpi_size_t usize, wsize, limb_cnt; + mpi_ptr_t wp; + mpi_limb_t wlimb; + int usign, wsign; + + usize = u->nlimbs; + usign = u->sign; + + if (!usize) { + w->nlimbs = 0; + w->sign = 0; + return 0; + } + + limb_cnt = cnt / BITS_PER_MPI_LIMB; + wsize = usize + limb_cnt + 1; + if (w->alloced < wsize) + if (mpi_resize(w, wsize) < 0) + return -ENOMEM; + wp = w->d; + wsize = usize + limb_cnt; + wsign = usign; + + cnt %= BITS_PER_MPI_LIMB; + if (cnt) { + wlimb = mpihelp_lshift(wp + limb_cnt, u->d, usize, cnt); + if (wlimb) { + wp[wsize] = wlimb; + wsize++; + } + } else { + MPN_COPY_DECR(wp + limb_cnt, u->d, usize); + } + + /* Zero all whole limbs at low end. Do it here and not before calling + * mpn_lshift, not to lose for U == W. */ + MPN_ZERO(wp, limb_cnt); + + w->nlimbs = wsize; + w->sign = wsign; + return 0; +} + +int mpi_mul(MPI w, MPI u, MPI v) +{ + int rc = -ENOMEM; + mpi_size_t usize, vsize, wsize; + mpi_ptr_t up, vp, wp; + mpi_limb_t cy; + int usign, vsign, sign_product; + int assign_wp = 0; + mpi_ptr_t tmp_limb = NULL; + + if (u->nlimbs < v->nlimbs) { /* Swap U and V. */ + usize = v->nlimbs; + usign = v->sign; + up = v->d; + vsize = u->nlimbs; + vsign = u->sign; + vp = u->d; + } else { + usize = u->nlimbs; + usign = u->sign; + up = u->d; + vsize = v->nlimbs; + vsign = v->sign; + vp = v->d; + } + sign_product = usign ^ vsign; + wp = w->d; + + /* Ensure W has space enough to store the result. */ + wsize = usize + vsize; + if (w->alloced < (size_t) wsize) { + if (wp == up || wp == vp) { + wp = mpi_alloc_limb_space(wsize); + if (!wp) + goto nomem; + assign_wp = 1; + } else { + if (mpi_resize(w, wsize) < 0) + goto nomem; + wp = w->d; + } + } else { /* Make U and V not overlap with W. */ + if (wp == up) { + /* W and U are identical. Allocate temporary space for U. */ + up = tmp_limb = mpi_alloc_limb_space(usize); + if (!up) + goto nomem; + /* Is V identical too? Keep it identical with U. */ + if (wp == vp) + vp = up; + /* Copy to the temporary space. */ + MPN_COPY(up, wp, usize); + } else if (wp == vp) { + /* W and V are identical. Allocate temporary space for V. */ + vp = tmp_limb = mpi_alloc_limb_space(vsize); + if (!vp) + goto nomem; + /* Copy to the temporary space. */ + MPN_COPY(vp, wp, vsize); + } + } + + if (!vsize) + wsize = 0; + else { + if (mpihelp_mul(wp, up, usize, vp, vsize, &cy) < 0) + goto nomem; + wsize -= cy ? 0 : 1; + } + + if (assign_wp) + mpi_assign_limb_space(w, wp, wsize); + + w->nlimbs = wsize; + w->sign = sign_product; + rc = 0; +nomem: + if (tmp_limb) + mpi_free_limb_space(tmp_limb); + return rc; +} + +int mpi_mulm(MPI w, MPI u, MPI v, MPI m) +{ + if (mpi_mul(w, u, v) < 0) + return -ENOMEM; + return mpi_fdiv_r(w, w, m); +} diff --git a/lib/mpi/mpi-scan.c b/lib/mpi/mpi-scan.c new file mode 100644 index 000000000000..b2da5ad96199 --- /dev/null +++ b/lib/mpi/mpi-scan.c @@ -0,0 +1,136 @@ +/* mpi-scan.c - MPI functions + * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include "mpi-internal.h" +#include "longlong.h" + +/**************** + * Scan through an mpi and return byte for byte. a -1 is returned to indicate + * the end of the mpi. Scanning is done from the lsb to the msb, returned + * values are in the range of 0 .. 255. + * + * FIXME: This code is VERY ugly! + */ +int mpi_getbyte(const MPI a, unsigned idx) +{ + int i, j; + unsigned n; + mpi_ptr_t ap; + mpi_limb_t limb; + + ap = a->d; + for (n = 0, i = 0; i < a->nlimbs; i++) { + limb = ap[i]; + for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++) + if (n == idx) + return (limb >> j * 8) & 0xff; + } + return -1; +} + +/**************** + * Put a value at position IDX into A. idx counts from lsb to msb + */ +void mpi_putbyte(MPI a, unsigned idx, int xc) +{ + int i, j; + unsigned n; + mpi_ptr_t ap; + mpi_limb_t limb, c; + + c = xc & 0xff; + ap = a->d; + for (n = 0, i = 0; i < a->alloced; i++) { + limb = ap[i]; + for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++) + if (n == idx) { +#if BYTES_PER_MPI_LIMB == 4 + if (j == 0) + limb = (limb & 0xffffff00) | c; + else if (j == 1) + limb = (limb & 0xffff00ff) | (c << 8); + else if (j == 2) + limb = (limb & 0xff00ffff) | (c << 16); + else + limb = (limb & 0x00ffffff) | (c << 24); +#elif BYTES_PER_MPI_LIMB == 8 + if (j == 0) + limb = (limb & 0xffffffffffffff00) | c; + else if (j == 1) + limb = + (limb & 0xffffffffffff00ff) | (c << + 8); + else if (j == 2) + limb = + (limb & 0xffffffffff00ffff) | (c << + 16); + else if (j == 3) + limb = + (limb & 0xffffffff00ffffff) | (c << + 24); + else if (j == 4) + limb = + (limb & 0xffffff00ffffffff) | (c << + 32); + else if (j == 5) + limb = + (limb & 0xffff00ffffffffff) | (c << + 40); + else if (j == 6) + limb = + (limb & 0xff00ffffffffffff) | (c << + 48); + else + limb = + (limb & 0x00ffffffffffffff) | (c << + 56); +#else +#error please enhance this function, its ugly - i know. +#endif + if (a->nlimbs <= i) + a->nlimbs = i + 1; + ap[i] = limb; + return; + } + } + log_bug("index out of range\n"); +} + +/**************** + * Count the number of zerobits at the low end of A + */ +unsigned mpi_trailing_zeros(const MPI a) +{ + unsigned n, count = 0; + + for (n = 0; n < a->nlimbs; n++) { + if (a->d[n]) { + unsigned nn; + mpi_limb_t alimb = a->d[n]; + + count_trailing_zeros(nn, alimb); + count += nn; + break; + } + count += BITS_PER_MPI_LIMB; + } + return count; + +} |