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authorDmitry Kasatkin <dmitry.kasatkin@intel.com>2012-05-09 10:37:55 -0400
committerJames Morris <james.l.morris@oracle.com>2012-05-25 21:50:44 -0400
commit9e235dcaf4f63d88a7e9ce5735ba5c2eb2719603 (patch)
treeb9eed6c4ee356996fd57a129b65730c087b4880d /lib
parent423b9788023263364ea5de04189f02bd9b6a12db (diff)
Revert "crypto: GnuPG based MPI lib - additional sources (part 4)"
This reverts commit 7e8dec918ef8e0f68b4937c3c50fa57002077a4d. RSA verification implementation does not use this code. James Morris has asked to remove that. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Requested-by: James Morris <james.l.morris@oracle.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig8
-rw-r--r--lib/mpi/Makefile11
-rw-r--r--lib/mpi/generic_mpi-asm-defs.h4
-rw-r--r--lib/mpi/mpi-add.c234
-rw-r--r--lib/mpi/mpi-cmp.c68
-rw-r--r--lib/mpi/mpi-div.c338
-rw-r--r--lib/mpi/mpi-gcd.c59
-rw-r--r--lib/mpi/mpi-inline.c31
-rw-r--r--lib/mpi/mpi-inv.c187
-rw-r--r--lib/mpi/mpi-mpow.c134
-rw-r--r--lib/mpi/mpi-mul.c194
-rw-r--r--lib/mpi/mpi-scan.c136
12 files changed, 0 insertions, 1404 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 4a8aba2e5cc0..ac9d8d31c4a6 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -361,14 +361,6 @@ config MPILIB
361 It is used to implement RSA digital signature verification, 361 It is used to implement RSA digital signature verification,
362 which is used by IMA/EVM digital signature extension. 362 which is used by IMA/EVM digital signature extension.
363 363
364config MPILIB_EXTRA
365 bool
366 depends on MPILIB
367 help
368 Additional sources of multiprecision maths library from GnuPG.
369 This code is unnecessary for RSA digital signature verification,
370 but can be compiled if needed.
371
372config SIGNATURE 364config SIGNATURE
373 tristate 365 tristate
374 depends on KEYS && CRYPTO 366 depends on KEYS && CRYPTO
diff --git a/lib/mpi/Makefile b/lib/mpi/Makefile
index 567d52e74d77..45ca90a8639c 100644
--- a/lib/mpi/Makefile
+++ b/lib/mpi/Makefile
@@ -19,14 +19,3 @@ mpi-y = \
19 mpih-mul.o \ 19 mpih-mul.o \
20 mpi-pow.o \ 20 mpi-pow.o \
21 mpiutil.o 21 mpiutil.o
22
23mpi-$(CONFIG_MPILIB_EXTRA) += \
24 mpi-add.o \
25 mpi-div.o \
26 mpi-cmp.o \
27 mpi-gcd.o \
28 mpi-inline.o \
29 mpi-inv.o \
30 mpi-mpow.o \
31 mpi-mul.o \
32 mpi-scan.o
diff --git a/lib/mpi/generic_mpi-asm-defs.h b/lib/mpi/generic_mpi-asm-defs.h
deleted file mode 100644
index 047d1f5a7249..000000000000
--- a/lib/mpi/generic_mpi-asm-defs.h
+++ /dev/null
@@ -1,4 +0,0 @@
1/* This file defines some basic constants for the MPI machinery. We
2 * need to define the types on a per-CPU basis, so it is done with
3 * this file here. */
4#define BYTES_PER_MPI_LIMB (SIZEOF_UNSIGNED_LONG)
diff --git a/lib/mpi/mpi-add.c b/lib/mpi/mpi-add.c
deleted file mode 100644
index f56b9ba295e6..000000000000
--- a/lib/mpi/mpi-add.c
+++ /dev/null
@@ -1,234 +0,0 @@
1/* mpi-add.c - MPI functions
2 * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
3 * Copyright (C) 1994, 1996 Free Software Foundation, Inc.
4 *
5 * This file is part of GnuPG.
6 *
7 * GnuPG is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * GnuPG is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
20 *
21 * Note: This code is heavily based on the GNU MP Library.
22 * Actually it's the same code with only minor changes in the
23 * way the data is stored; this is to support the abstraction
24 * of an optional secure memory allocation which may be used
25 * to avoid revealing of sensitive data due to paging etc.
26 * The GNU MP Library itself is published under the LGPL;
27 * however I decided to publish this code under the plain GPL.
28 */
29
30#include "mpi-internal.h"
31
32/****************
33 * Add the unsigned integer V to the mpi-integer U and store the
34 * result in W. U and V may be the same.
35 */
36int mpi_add_ui(MPI w, const MPI u, unsigned long v)
37{
38 mpi_ptr_t wp, up;
39 mpi_size_t usize, wsize;
40 int usign, wsign;
41
42 usize = u->nlimbs;
43 usign = u->sign;
44 wsign = 0;
45
46 /* If not space for W (and possible carry), increase space. */
47 wsize = usize + 1;
48 if (w->alloced < wsize)
49 if (mpi_resize(w, wsize) < 0)
50 return -ENOMEM;
51
52 /* These must be after realloc (U may be the same as W). */
53 up = u->d;
54 wp = w->d;
55
56 if (!usize) { /* simple */
57 wp[0] = v;
58 wsize = v ? 1 : 0;
59 } else if (!usign) { /* mpi is not negative */
60 mpi_limb_t cy;
61 cy = mpihelp_add_1(wp, up, usize, v);
62 wp[usize] = cy;
63 wsize = usize + cy;
64 } else { /* The signs are different. Need exact comparison to determine
65 * which operand to subtract from which. */
66 if (usize == 1 && up[0] < v) {
67 wp[0] = v - up[0];
68 wsize = 1;
69 } else {
70 mpihelp_sub_1(wp, up, usize, v);
71 /* Size can decrease with at most one limb. */
72 wsize = usize - (wp[usize - 1] == 0);
73 wsign = 1;
74 }
75 }
76
77 w->nlimbs = wsize;
78 w->sign = wsign;
79 return 0;
80}
81
82int mpi_add(MPI w, MPI u, MPI v)
83{
84 mpi_ptr_t wp, up, vp;
85 mpi_size_t usize, vsize, wsize;
86 int usign, vsign, wsign;
87
88 if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
89 usize = v->nlimbs;
90 usign = v->sign;
91 vsize = u->nlimbs;
92 vsign = u->sign;
93 wsize = usize + 1;
94 if (RESIZE_IF_NEEDED(w, wsize) < 0)
95 return -ENOMEM;
96 /* These must be after realloc (u or v may be the same as w). */
97 up = v->d;
98 vp = u->d;
99 } else {
100 usize = u->nlimbs;
101 usign = u->sign;
102 vsize = v->nlimbs;
103 vsign = v->sign;
104 wsize = usize + 1;
105 if (RESIZE_IF_NEEDED(w, wsize) < 0)
106 return -ENOMEM;
107 /* These must be after realloc (u or v may be the same as w). */
108 up = u->d;
109 vp = v->d;
110 }
111 wp = w->d;
112 wsign = 0;
113
114 if (!vsize) { /* simple */
115 MPN_COPY(wp, up, usize);
116 wsize = usize;
117 wsign = usign;
118 } else if (usign != vsign) { /* different sign */
119 /* This test is right since USIZE >= VSIZE */
120 if (usize != vsize) {
121 mpihelp_sub(wp, up, usize, vp, vsize);
122 wsize = usize;
123 MPN_NORMALIZE(wp, wsize);
124 wsign = usign;
125 } else if (mpihelp_cmp(up, vp, usize) < 0) {
126 mpihelp_sub_n(wp, vp, up, usize);
127 wsize = usize;
128 MPN_NORMALIZE(wp, wsize);
129 if (!usign)
130 wsign = 1;
131 } else {
132 mpihelp_sub_n(wp, up, vp, usize);
133 wsize = usize;
134 MPN_NORMALIZE(wp, wsize);
135 if (usign)
136 wsign = 1;
137 }
138 } else { /* U and V have same sign. Add them. */
139 mpi_limb_t cy = mpihelp_add(wp, up, usize, vp, vsize);
140 wp[usize] = cy;
141 wsize = usize + cy;
142 if (usign)
143 wsign = 1;
144 }
145
146 w->nlimbs = wsize;
147 w->sign = wsign;
148 return 0;
149}
150
151/****************
152 * Subtract the unsigned integer V from the mpi-integer U and store the
153 * result in W.
154 */
155int mpi_sub_ui(MPI w, MPI u, unsigned long v)
156{
157 mpi_ptr_t wp, up;
158 mpi_size_t usize, wsize;
159 int usign, wsign;
160
161 usize = u->nlimbs;
162 usign = u->sign;
163 wsign = 0;
164
165 /* If not space for W (and possible carry), increase space. */
166 wsize = usize + 1;
167 if (w->alloced < wsize)
168 if (mpi_resize(w, wsize) < 0)
169 return -ENOMEM;
170
171 /* These must be after realloc (U may be the same as W). */
172 up = u->d;
173 wp = w->d;
174
175 if (!usize) { /* simple */
176 wp[0] = v;
177 wsize = v ? 1 : 0;
178 wsign = 1;
179 } else if (usign) { /* mpi and v are negative */
180 mpi_limb_t cy;
181 cy = mpihelp_add_1(wp, up, usize, v);
182 wp[usize] = cy;
183 wsize = usize + cy;
184 } else { /* The signs are different. Need exact comparison to determine
185 * which operand to subtract from which. */
186 if (usize == 1 && up[0] < v) {
187 wp[0] = v - up[0];
188 wsize = 1;
189 wsign = 1;
190 } else {
191 mpihelp_sub_1(wp, up, usize, v);
192 /* Size can decrease with at most one limb. */
193 wsize = usize - (wp[usize - 1] == 0);
194 }
195 }
196
197 w->nlimbs = wsize;
198 w->sign = wsign;
199 return 0;
200}
201
202int mpi_sub(MPI w, MPI u, MPI v)
203{
204 int rc;
205
206 if (w == v) {
207 MPI vv;
208 if (mpi_copy(&vv, v) < 0)
209 return -ENOMEM;
210 vv->sign = !vv->sign;
211 rc = mpi_add(w, u, vv);
212 mpi_free(vv);
213 } else {
214 /* fixme: this is not thread-save (we temp. modify v) */
215 v->sign = !v->sign;
216 rc = mpi_add(w, u, v);
217 v->sign = !v->sign;
218 }
219 return rc;
220}
221
222int mpi_addm(MPI w, MPI u, MPI v, MPI m)
223{
224 if (mpi_add(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0)
225 return -ENOMEM;
226 return 0;
227}
228
229int mpi_subm(MPI w, MPI u, MPI v, MPI m)
230{
231 if (mpi_sub(w, u, v) < 0 || mpi_fdiv_r(w, w, m) < 0)
232 return -ENOMEM;
233 return 0;
234}
diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c
deleted file mode 100644
index 914bc42a8a80..000000000000
--- a/lib/mpi/mpi-cmp.c
+++ /dev/null
@@ -1,68 +0,0 @@
1/* mpi-cmp.c - MPI functions
2 * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22
23int mpi_cmp_ui(MPI u, unsigned long v)
24{
25 mpi_limb_t limb = v;
26
27 mpi_normalize(u);
28 if (!u->nlimbs && !limb)
29 return 0;
30 if (u->sign)
31 return -1;
32 if (u->nlimbs > 1)
33 return 1;
34
35 if (u->d[0] == limb)
36 return 0;
37 else if (u->d[0] > limb)
38 return 1;
39 else
40 return -1;
41}
42
43int mpi_cmp(MPI u, MPI v)
44{
45 mpi_size_t usize, vsize;
46 int cmp;
47
48 mpi_normalize(u);
49 mpi_normalize(v);
50 usize = u->nlimbs;
51 vsize = v->nlimbs;
52 if (!u->sign && v->sign)
53 return 1;
54 if (u->sign && !v->sign)
55 return -1;
56 if (usize != vsize && !u->sign && !v->sign)
57 return usize - vsize;
58 if (usize != vsize && u->sign && v->sign)
59 return vsize + usize;
60 if (!usize)
61 return 0;
62 cmp = mpihelp_cmp(u->d, v->d, usize);
63 if (!cmp)
64 return 0;
65 if ((cmp < 0 ? 1 : 0) == (u->sign ? 1 : 0))
66 return 1;
67 return -1;
68}
diff --git a/lib/mpi/mpi-div.c b/lib/mpi/mpi-div.c
deleted file mode 100644
index f68cbbb4d4a4..000000000000
--- a/lib/mpi/mpi-div.c
+++ /dev/null
@@ -1,338 +0,0 @@
1/* mpi-div.c - MPI functions
2 * Copyright (C) 1994, 1996 Free Software Foundation, Inc.
3 * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
4 *
5 * This file is part of GnuPG.
6 *
7 * GnuPG is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * GnuPG is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
20 *
21 * Note: This code is heavily based on the GNU MP Library.
22 * Actually it's the same code with only minor changes in the
23 * way the data is stored; this is to support the abstraction
24 * of an optional secure memory allocation which may be used
25 * to avoid revealing of sensitive data due to paging etc.
26 * The GNU MP Library itself is published under the LGPL;
27 * however I decided to publish this code under the plain GPL.
28 */
29
30#include <linux/string.h>
31#include "mpi-internal.h"
32#include "longlong.h"
33
34int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
35{
36 int rc = -ENOMEM;
37 int divisor_sign = divisor->sign;
38 MPI temp_divisor = NULL;
39
40 /* We need the original value of the divisor after the remainder has been
41 * preliminary calculated. We have to copy it to temporary space if it's
42 * the same variable as REM. */
43 if (rem == divisor) {
44 if (mpi_copy(&temp_divisor, divisor) < 0)
45 goto nomem;
46 divisor = temp_divisor;
47 }
48
49 if (mpi_tdiv_qr(NULL, rem, dividend, divisor) < 0)
50 goto nomem;
51 if (((divisor_sign ? 1 : 0) ^ (dividend->sign ? 1 : 0)) && rem->nlimbs)
52 if (mpi_add(rem, rem, divisor) < 0)
53 goto nomem;
54
55 rc = 0;
56
57nomem:
58 if (temp_divisor)
59 mpi_free(temp_divisor);
60 return rc;
61}
62
63/****************
64 * Division rounding the quotient towards -infinity.
65 * The remainder gets the same sign as the denominator.
66 * rem is optional
67 */
68
69ulong mpi_fdiv_r_ui(MPI rem, MPI dividend, ulong divisor)
70{
71 mpi_limb_t rlimb;
72
73 rlimb = mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor);
74 if (rlimb && dividend->sign)
75 rlimb = divisor - rlimb;
76
77 if (rem) {
78 rem->d[0] = rlimb;
79 rem->nlimbs = rlimb ? 1 : 0;
80 }
81 return rlimb;
82}
83
84int mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor)
85{
86 MPI tmp = mpi_alloc(mpi_get_nlimbs(quot));
87 if (!tmp)
88 return -ENOMEM;
89 mpi_fdiv_qr(quot, tmp, dividend, divisor);
90 mpi_free(tmp);
91 return 0;
92}
93
94int mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor)
95{
96 int divisor_sign = divisor->sign;
97 MPI temp_divisor = NULL;
98
99 if (quot == divisor || rem == divisor) {
100 if (mpi_copy(&temp_divisor, divisor) < 0)
101 return -ENOMEM;
102 divisor = temp_divisor;
103 }
104
105 if (mpi_tdiv_qr(quot, rem, dividend, divisor) < 0)
106 goto nomem;
107
108 if ((divisor_sign ^ dividend->sign) && rem->nlimbs) {
109 if (mpi_sub_ui(quot, quot, 1) < 0)
110 goto nomem;
111 if (mpi_add(rem, rem, divisor) < 0)
112 goto nomem;
113 }
114
115 if (temp_divisor)
116 mpi_free(temp_divisor);
117
118 return 0;
119
120nomem:
121 mpi_free(temp_divisor);
122 return -ENOMEM;
123}
124
125/* If den == quot, den needs temporary storage.
126 * If den == rem, den needs temporary storage.
127 * If num == quot, num needs temporary storage.
128 * If den has temporary storage, it can be normalized while being copied,
129 * i.e no extra storage should be allocated.
130 */
131
132int mpi_tdiv_r(MPI rem, MPI num, MPI den)
133{
134 return mpi_tdiv_qr(NULL, rem, num, den);
135}
136
137int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
138{
139 int rc = -ENOMEM;
140 mpi_ptr_t np, dp;
141 mpi_ptr_t qp, rp;
142 mpi_size_t nsize = num->nlimbs;
143 mpi_size_t dsize = den->nlimbs;
144 mpi_size_t qsize, rsize;
145 mpi_size_t sign_remainder = num->sign;
146 mpi_size_t sign_quotient = num->sign ^ den->sign;
147 unsigned normalization_steps;
148 mpi_limb_t q_limb;
149 mpi_ptr_t marker[5];
150 int markidx = 0;
151
152 if (!dsize)
153 return -EINVAL;
154
155 memset(marker, 0, sizeof(marker));
156
157 /* Ensure space is enough for quotient and remainder.
158 * We need space for an extra limb in the remainder, because it's
159 * up-shifted (normalized) below. */
160 rsize = nsize + 1;
161 if (mpi_resize(rem, rsize) < 0)
162 goto nomem;
163
164 qsize = rsize - dsize; /* qsize cannot be bigger than this. */
165 if (qsize <= 0) {
166 if (num != rem) {
167 rem->nlimbs = num->nlimbs;
168 rem->sign = num->sign;
169 MPN_COPY(rem->d, num->d, nsize);
170 }
171 if (quot) {
172 /* This needs to follow the assignment to rem, in case the
173 * numerator and quotient are the same. */
174 quot->nlimbs = 0;
175 quot->sign = 0;
176 }
177 return 0;
178 }
179
180 if (quot)
181 if (mpi_resize(quot, qsize) < 0)
182 goto nomem;
183
184 /* Read pointers here, when reallocation is finished. */
185 np = num->d;
186 dp = den->d;
187 rp = rem->d;
188
189 /* Optimize division by a single-limb divisor. */
190 if (dsize == 1) {
191 mpi_limb_t rlimb;
192 if (quot) {
193 qp = quot->d;
194 rlimb = mpihelp_divmod_1(qp, np, nsize, dp[0]);
195 qsize -= qp[qsize - 1] == 0;
196 quot->nlimbs = qsize;
197 quot->sign = sign_quotient;
198 } else
199 rlimb = mpihelp_mod_1(np, nsize, dp[0]);
200 rp[0] = rlimb;
201 rsize = rlimb != 0 ? 1 : 0;
202 rem->nlimbs = rsize;
203 rem->sign = sign_remainder;
204 return 0;
205 }
206
207 if (quot) {
208 qp = quot->d;
209 /* Make sure QP and NP point to different objects. Otherwise the
210 * numerator would be gradually overwritten by the quotient limbs. */
211 if (qp == np) { /* Copy NP object to temporary space. */
212 np = marker[markidx++] = mpi_alloc_limb_space(nsize);
213 if (!np)
214 goto nomem;
215 MPN_COPY(np, qp, nsize);
216 }
217 } else /* Put quotient at top of remainder. */
218 qp = rp + dsize;
219
220 count_leading_zeros(normalization_steps, dp[dsize - 1]);
221
222 /* Normalize the denominator, i.e. make its most significant bit set by
223 * shifting it NORMALIZATION_STEPS bits to the left. Also shift the
224 * numerator the same number of steps (to keep the quotient the same!).
225 */
226 if (normalization_steps) {
227 mpi_ptr_t tp;
228 mpi_limb_t nlimb;
229
230 /* Shift up the denominator setting the most significant bit of
231 * the most significant word. Use temporary storage not to clobber
232 * the original contents of the denominator. */
233 tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
234 if (!tp)
235 goto nomem;
236 mpihelp_lshift(tp, dp, dsize, normalization_steps);
237 dp = tp;
238
239 /* Shift up the numerator, possibly introducing a new most
240 * significant word. Move the shifted numerator in the remainder
241 * meanwhile. */
242 nlimb = mpihelp_lshift(rp, np, nsize, normalization_steps);
243 if (nlimb) {
244 rp[nsize] = nlimb;
245 rsize = nsize + 1;
246 } else
247 rsize = nsize;
248 } else {
249 /* The denominator is already normalized, as required. Copy it to
250 * temporary space if it overlaps with the quotient or remainder. */
251 if (dp == rp || (quot && (dp == qp))) {
252 mpi_ptr_t tp;
253
254 tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
255 if (!tp)
256 goto nomem;
257 MPN_COPY(tp, dp, dsize);
258 dp = tp;
259 }
260
261 /* Move the numerator to the remainder. */
262 if (rp != np)
263 MPN_COPY(rp, np, nsize);
264
265 rsize = nsize;
266 }
267
268 q_limb = mpihelp_divrem(qp, 0, rp, rsize, dp, dsize);
269
270 if (quot) {
271 qsize = rsize - dsize;
272 if (q_limb) {
273 qp[qsize] = q_limb;
274 qsize += 1;
275 }
276
277 quot->nlimbs = qsize;
278 quot->sign = sign_quotient;
279 }
280
281 rsize = dsize;
282 MPN_NORMALIZE(rp, rsize);
283
284 if (normalization_steps && rsize) {
285 mpihelp_rshift(rp, rp, rsize, normalization_steps);
286 rsize -= rp[rsize - 1] == 0 ? 1 : 0;
287 }
288
289 rem->nlimbs = rsize;
290 rem->sign = sign_remainder;
291
292 rc = 0;
293nomem:
294 while (markidx)
295 mpi_free_limb_space(marker[--markidx]);
296 return rc;
297}
298
299int mpi_tdiv_q_2exp(MPI w, MPI u, unsigned count)
300{
301 mpi_size_t usize, wsize;
302 mpi_size_t limb_cnt;
303
304 usize = u->nlimbs;
305 limb_cnt = count / BITS_PER_MPI_LIMB;
306 wsize = usize - limb_cnt;
307 if (limb_cnt >= usize)
308 w->nlimbs = 0;
309 else {
310 mpi_ptr_t wp;
311 mpi_ptr_t up;
312
313 if (RESIZE_IF_NEEDED(w, wsize) < 0)
314 return -ENOMEM;
315 wp = w->d;
316 up = u->d;
317
318 count %= BITS_PER_MPI_LIMB;
319 if (count) {
320 mpihelp_rshift(wp, up + limb_cnt, wsize, count);
321 wsize -= !wp[wsize - 1];
322 } else {
323 MPN_COPY_INCR(wp, up + limb_cnt, wsize);
324 }
325
326 w->nlimbs = wsize;
327 }
328 return 0;
329}
330
331/****************
332 * Check whether dividend is divisible by divisor
333 * (note: divisor must fit into a limb)
334 */
335int mpi_divisible_ui(MPI dividend, ulong divisor)
336{
337 return !mpihelp_mod_1(dividend->d, dividend->nlimbs, divisor);
338}
diff --git a/lib/mpi/mpi-gcd.c b/lib/mpi/mpi-gcd.c
deleted file mode 100644
index 13c48aef9c4e..000000000000
--- a/lib/mpi/mpi-gcd.c
+++ /dev/null
@@ -1,59 +0,0 @@
1/* mpi-gcd.c - MPI functions
2 * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22
23/****************
24 * Find the greatest common divisor G of A and B.
25 * Return: true if this 1, false in all other cases
26 */
27int mpi_gcd(MPI g, const MPI xa, const MPI xb)
28{
29 MPI a = NULL, b = NULL;
30
31 if (mpi_copy(&a, xa) < 0)
32 goto nomem;
33
34 if (mpi_copy(&b, xb) < 0)
35 goto nomem;
36
37 /* TAOCP Vol II, 4.5.2, Algorithm A */
38 a->sign = 0;
39 b->sign = 0;
40 while (mpi_cmp_ui(b, 0)) {
41 if (mpi_fdiv_r(g, a, b) < 0) /* g used as temorary variable */
42 goto nomem;
43 if (mpi_set(a, b) < 0)
44 goto nomem;
45 if (mpi_set(b, g) < 0)
46 goto nomem;
47 }
48 if (mpi_set(g, a) < 0)
49 goto nomem;
50
51 mpi_free(a);
52 mpi_free(b);
53 return !mpi_cmp_ui(g, 1);
54
55nomem:
56 mpi_free(a);
57 mpi_free(b);
58 return -ENOMEM;
59}
diff --git a/lib/mpi/mpi-inline.c b/lib/mpi/mpi-inline.c
deleted file mode 100644
index 654f68aeed8b..000000000000
--- a/lib/mpi/mpi-inline.c
+++ /dev/null
@@ -1,31 +0,0 @@
1/* mpi-inline.c
2 * Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21/* put the inline functions as real functions into the lib */
22#define G10_MPI_INLINE_DECL
23
24#include "mpi-internal.h"
25
26/* always include the header becuase it is only
27 * included by mpi-internal if __GCC__ is defined but we
28 * need it here in all cases and the above definition of
29 * of the macro allows us to do so
30 */
31#include "mpi-inline.h"
diff --git a/lib/mpi/mpi-inv.c b/lib/mpi/mpi-inv.c
deleted file mode 100644
index 0951f9847745..000000000000
--- a/lib/mpi/mpi-inv.c
+++ /dev/null
@@ -1,187 +0,0 @@
1/* mpi-inv.c - MPI functions
2 * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22
23/****************
24 * Calculate the multiplicative inverse X of A mod N
25 * That is: Find the solution x for
26 * 1 = (a*x) mod n
27 */
28int mpi_invm(MPI x, const MPI a, const MPI n)
29{
30 /* Extended Euclid's algorithm (See TAOPC Vol II, 4.5.2, Alg X)
31 * modified according to Michael Penk's solution for Exercice 35
32 * with further enhancement */
33 MPI u = NULL, v = NULL;
34 MPI u1 = NULL, u2 = NULL, u3 = NULL;
35 MPI v1 = NULL, v2 = NULL, v3 = NULL;
36 MPI t1 = NULL, t2 = NULL, t3 = NULL;
37 unsigned k;
38 int sign;
39 int odd = 0;
40 int rc = -ENOMEM;
41
42 if (mpi_copy(&u, a) < 0)
43 goto cleanup;
44 if (mpi_copy(&v, n) < 0)
45 goto cleanup;
46
47 for (k = 0; !mpi_test_bit(u, 0) && !mpi_test_bit(v, 0); k++) {
48 if (mpi_rshift(u, u, 1) < 0)
49 goto cleanup;
50 if (mpi_rshift(v, v, 1) < 0)
51 goto cleanup;
52 }
53 odd = mpi_test_bit(v, 0);
54
55 u1 = mpi_alloc_set_ui(1);
56 if (!u1)
57 goto cleanup;
58 if (!odd) {
59 u2 = mpi_alloc_set_ui(0);
60 if (!u2)
61 goto cleanup;
62 }
63 if (mpi_copy(&u3, u) < 0)
64 goto cleanup;
65 if (mpi_copy(&v1, v) < 0)
66 goto cleanup;
67 if (!odd) {
68 v2 = mpi_alloc(mpi_get_nlimbs(u));
69 if (!v2)
70 goto cleanup;
71 if (mpi_sub(v2, u1, u) < 0)
72 goto cleanup; /* U is used as const 1 */
73 }
74 if (mpi_copy(&v3, v) < 0)
75 goto cleanup;
76 if (mpi_test_bit(u, 0)) { /* u is odd */
77 t1 = mpi_alloc_set_ui(0);
78 if (!t1)
79 goto cleanup;
80 if (!odd) {
81 t2 = mpi_alloc_set_ui(1);
82 if (!t2)
83 goto cleanup;
84 t2->sign = 1;
85 }
86 if (mpi_copy(&t3, v) < 0)
87 goto cleanup;
88 t3->sign = !t3->sign;
89 goto Y4;
90 } else {
91 t1 = mpi_alloc_set_ui(1);
92 if (!t1)
93 goto cleanup;
94 if (!odd) {
95 t2 = mpi_alloc_set_ui(0);
96 if (!t2)
97 goto cleanup;
98 }
99 if (mpi_copy(&t3, u) < 0)
100 goto cleanup;
101 }
102 do {
103 do {
104 if (!odd) {
105 if (mpi_test_bit(t1, 0) || mpi_test_bit(t2, 0)) { /* one is odd */
106 if (mpi_add(t1, t1, v) < 0)
107 goto cleanup;
108 if (mpi_sub(t2, t2, u) < 0)
109 goto cleanup;
110 }
111 if (mpi_rshift(t1, t1, 1) < 0)
112 goto cleanup;
113 if (mpi_rshift(t2, t2, 1) < 0)
114 goto cleanup;
115 if (mpi_rshift(t3, t3, 1) < 0)
116 goto cleanup;
117 } else {
118 if (mpi_test_bit(t1, 0))
119 if (mpi_add(t1, t1, v) < 0)
120 goto cleanup;
121 if (mpi_rshift(t1, t1, 1) < 0)
122 goto cleanup;
123 if (mpi_rshift(t3, t3, 1) < 0)
124 goto cleanup;
125 }
126Y4:
127 ;
128 } while (!mpi_test_bit(t3, 0)); /* while t3 is even */
129
130 if (!t3->sign) {
131 if (mpi_set(u1, t1) < 0)
132 goto cleanup;
133 if (!odd)
134 if (mpi_set(u2, t2) < 0)
135 goto cleanup;
136 if (mpi_set(u3, t3) < 0)
137 goto cleanup;
138 } else {
139 if (mpi_sub(v1, v, t1) < 0)
140 goto cleanup;
141 sign = u->sign;
142 u->sign = !u->sign;
143 if (!odd)
144 if (mpi_sub(v2, u, t2) < 0)
145 goto cleanup;
146 u->sign = sign;
147 sign = t3->sign;
148 t3->sign = !t3->sign;
149 if (mpi_set(v3, t3) < 0)
150 goto cleanup;
151 t3->sign = sign;
152 }
153 if (mpi_sub(t1, u1, v1) < 0)
154 goto cleanup;
155 if (!odd)
156 if (mpi_sub(t2, u2, v2) < 0)
157 goto cleanup;
158 if (mpi_sub(t3, u3, v3) < 0)
159 goto cleanup;
160 if (t1->sign) {
161 if (mpi_add(t1, t1, v) < 0)
162 goto cleanup;
163 if (!odd)
164 if (mpi_sub(t2, t2, u) < 0)
165 goto cleanup;
166 }
167 } while (mpi_cmp_ui(t3, 0)); /* while t3 != 0 */
168 /* mpi_lshift( u3, k ); */
169 rc = mpi_set(x, u1);
170
171cleanup:
172 mpi_free(u1);
173 mpi_free(v1);
174 mpi_free(t1);
175 if (!odd) {
176 mpi_free(u2);
177 mpi_free(v2);
178 mpi_free(t2);
179 }
180 mpi_free(u3);
181 mpi_free(v3);
182 mpi_free(t3);
183
184 mpi_free(u);
185 mpi_free(v);
186 return rc;
187}
diff --git a/lib/mpi/mpi-mpow.c b/lib/mpi/mpi-mpow.c
deleted file mode 100644
index 7328d0d6c748..000000000000
--- a/lib/mpi/mpi-mpow.c
+++ /dev/null
@@ -1,134 +0,0 @@
1/* mpi-mpow.c - MPI functions
2 * Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22#include "longlong.h"
23
24static int build_index(const MPI *exparray, int k, int i, int t)
25{
26 int j, bitno;
27 int index = 0;
28
29 bitno = t - i;
30 for (j = k - 1; j >= 0; j--) {
31 index <<= 1;
32 if (mpi_test_bit(exparray[j], bitno))
33 index |= 1;
34 }
35 return index;
36}
37
38/****************
39 * RES = (BASE[0] ^ EXP[0]) * (BASE[1] ^ EXP[1]) * ... * mod M
40 */
41int mpi_mulpowm(MPI res, MPI *basearray, MPI *exparray, MPI m)
42{
43 int rc = -ENOMEM;
44 int k; /* number of elements */
45 int t; /* bit size of largest exponent */
46 int i, j, idx;
47 MPI *G = NULL; /* table with precomputed values of size 2^k */
48 MPI tmp = NULL;
49
50 for (k = 0; basearray[k]; k++)
51 ;
52 if (!k) {
53 pr_emerg("mpi_mulpowm: assert(k) failed\n");
54 BUG();
55 }
56 for (t = 0, i = 0; (tmp = exparray[i]); i++) {
57 j = mpi_get_nbits(tmp);
58 if (j > t)
59 t = j;
60 }
61 if (i != k) {
62 pr_emerg("mpi_mulpowm: assert(i==k) failed\n");
63 BUG();
64 }
65 if (!t) {
66 pr_emerg("mpi_mulpowm: assert(t) failed\n");
67 BUG();
68 }
69 if (k >= 10) {
70 pr_emerg("mpi_mulpowm: assert(k<10) failed\n");
71 BUG();
72 }
73
74 G = kzalloc((1 << k) * sizeof *G, GFP_KERNEL);
75 if (!G)
76 goto err_out;
77
78 /* and calculate */
79 tmp = mpi_alloc(mpi_get_nlimbs(m) + 1);
80 if (!tmp)
81 goto nomem;
82 if (mpi_set_ui(res, 1) < 0)
83 goto nomem;
84 for (i = 1; i <= t; i++) {
85 if (mpi_mulm(tmp, res, res, m) < 0)
86 goto nomem;
87 idx = build_index(exparray, k, i, t);
88 if (!(idx >= 0 && idx < (1 << k))) {
89 pr_emerg("mpi_mulpowm: assert(idx >= 0 && idx < (1<<k)) failed\n");
90 BUG();
91 }
92 if (!G[idx]) {
93 if (!idx) {
94 G[0] = mpi_alloc_set_ui(1);
95 if (!G[0])
96 goto nomem;
97 } else {
98 for (j = 0; j < k; j++) {
99 if ((idx & (1 << j))) {
100 if (!G[idx]) {
101 if (mpi_copy
102 (&G[idx],
103 basearray[j]) < 0)
104 goto nomem;
105 } else {
106 if (mpi_mulm
107 (G[idx], G[idx],
108 basearray[j],
109 m) < 0)
110 goto nomem;
111 }
112 }
113 }
114 if (!G[idx]) {
115 G[idx] = mpi_alloc(0);
116 if (!G[idx])
117 goto nomem;
118 }
119 }
120 }
121 if (mpi_mulm(res, tmp, G[idx], m) < 0)
122 goto nomem;
123 }
124
125 rc = 0;
126nomem:
127 /* cleanup */
128 mpi_free(tmp);
129 for (i = 0; i < (1 << k); i++)
130 mpi_free(G[i]);
131 kfree(G);
132err_out:
133 return rc;
134}
diff --git a/lib/mpi/mpi-mul.c b/lib/mpi/mpi-mul.c
deleted file mode 100644
index 1f3219e27292..000000000000
--- a/lib/mpi/mpi-mul.c
+++ /dev/null
@@ -1,194 +0,0 @@
1/* mpi-mul.c - MPI functions
2 * Copyright (C) 1994, 1996 Free Software Foundation, Inc.
3 * Copyright (C) 1998, 2001 Free Software Foundation, Inc.
4 *
5 * This file is part of GnuPG.
6 *
7 * GnuPG is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * GnuPG is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
20 *
21 * Note: This code is heavily based on the GNU MP Library.
22 * Actually it's the same code with only minor changes in the
23 * way the data is stored; this is to support the abstraction
24 * of an optional secure memory allocation which may be used
25 * to avoid revealing of sensitive data due to paging etc.
26 * The GNU MP Library itself is published under the LGPL;
27 * however I decided to publish this code under the plain GPL.
28 */
29
30#include "mpi-internal.h"
31
32int mpi_mul_ui(MPI prod, MPI mult, unsigned long small_mult)
33{
34 mpi_size_t size, prod_size;
35 mpi_ptr_t prod_ptr;
36 mpi_limb_t cy;
37 int sign;
38
39 size = mult->nlimbs;
40 sign = mult->sign;
41
42 if (!size || !small_mult) {
43 prod->nlimbs = 0;
44 prod->sign = 0;
45 return 0;
46 }
47
48 prod_size = size + 1;
49 if (prod->alloced < prod_size)
50 if (mpi_resize(prod, prod_size) < 0)
51 return -ENOMEM;
52 prod_ptr = prod->d;
53
54 cy = mpihelp_mul_1(prod_ptr, mult->d, size, (mpi_limb_t) small_mult);
55 if (cy)
56 prod_ptr[size++] = cy;
57 prod->nlimbs = size;
58 prod->sign = sign;
59 return 0;
60}
61
62int mpi_mul_2exp(MPI w, MPI u, unsigned long cnt)
63{
64 mpi_size_t usize, wsize, limb_cnt;
65 mpi_ptr_t wp;
66 mpi_limb_t wlimb;
67 int usign, wsign;
68
69 usize = u->nlimbs;
70 usign = u->sign;
71
72 if (!usize) {
73 w->nlimbs = 0;
74 w->sign = 0;
75 return 0;
76 }
77
78 limb_cnt = cnt / BITS_PER_MPI_LIMB;
79 wsize = usize + limb_cnt + 1;
80 if (w->alloced < wsize)
81 if (mpi_resize(w, wsize) < 0)
82 return -ENOMEM;
83 wp = w->d;
84 wsize = usize + limb_cnt;
85 wsign = usign;
86
87 cnt %= BITS_PER_MPI_LIMB;
88 if (cnt) {
89 wlimb = mpihelp_lshift(wp + limb_cnt, u->d, usize, cnt);
90 if (wlimb) {
91 wp[wsize] = wlimb;
92 wsize++;
93 }
94 } else {
95 MPN_COPY_DECR(wp + limb_cnt, u->d, usize);
96 }
97
98 /* Zero all whole limbs at low end. Do it here and not before calling
99 * mpn_lshift, not to lose for U == W. */
100 MPN_ZERO(wp, limb_cnt);
101
102 w->nlimbs = wsize;
103 w->sign = wsign;
104 return 0;
105}
106
107int mpi_mul(MPI w, MPI u, MPI v)
108{
109 int rc = -ENOMEM;
110 mpi_size_t usize, vsize, wsize;
111 mpi_ptr_t up, vp, wp;
112 mpi_limb_t cy;
113 int usign, vsign, sign_product;
114 int assign_wp = 0;
115 mpi_ptr_t tmp_limb = NULL;
116
117 if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
118 usize = v->nlimbs;
119 usign = v->sign;
120 up = v->d;
121 vsize = u->nlimbs;
122 vsign = u->sign;
123 vp = u->d;
124 } else {
125 usize = u->nlimbs;
126 usign = u->sign;
127 up = u->d;
128 vsize = v->nlimbs;
129 vsign = v->sign;
130 vp = v->d;
131 }
132 sign_product = usign ^ vsign;
133 wp = w->d;
134
135 /* Ensure W has space enough to store the result. */
136 wsize = usize + vsize;
137 if (w->alloced < (size_t) wsize) {
138 if (wp == up || wp == vp) {
139 wp = mpi_alloc_limb_space(wsize);
140 if (!wp)
141 goto nomem;
142 assign_wp = 1;
143 } else {
144 if (mpi_resize(w, wsize) < 0)
145 goto nomem;
146 wp = w->d;
147 }
148 } else { /* Make U and V not overlap with W. */
149 if (wp == up) {
150 /* W and U are identical. Allocate temporary space for U. */
151 up = tmp_limb = mpi_alloc_limb_space(usize);
152 if (!up)
153 goto nomem;
154 /* Is V identical too? Keep it identical with U. */
155 if (wp == vp)
156 vp = up;
157 /* Copy to the temporary space. */
158 MPN_COPY(up, wp, usize);
159 } else if (wp == vp) {
160 /* W and V are identical. Allocate temporary space for V. */
161 vp = tmp_limb = mpi_alloc_limb_space(vsize);
162 if (!vp)
163 goto nomem;
164 /* Copy to the temporary space. */
165 MPN_COPY(vp, wp, vsize);
166 }
167 }
168
169 if (!vsize)
170 wsize = 0;
171 else {
172 if (mpihelp_mul(wp, up, usize, vp, vsize, &cy) < 0)
173 goto nomem;
174 wsize -= cy ? 0 : 1;
175 }
176
177 if (assign_wp)
178 mpi_assign_limb_space(w, wp, wsize);
179
180 w->nlimbs = wsize;
181 w->sign = sign_product;
182 rc = 0;
183nomem:
184 if (tmp_limb)
185 mpi_free_limb_space(tmp_limb);
186 return rc;
187}
188
189int mpi_mulm(MPI w, MPI u, MPI v, MPI m)
190{
191 if (mpi_mul(w, u, v) < 0)
192 return -ENOMEM;
193 return mpi_fdiv_r(w, w, m);
194}
diff --git a/lib/mpi/mpi-scan.c b/lib/mpi/mpi-scan.c
deleted file mode 100644
index b2da5ad96199..000000000000
--- a/lib/mpi/mpi-scan.c
+++ /dev/null
@@ -1,136 +0,0 @@
1/* mpi-scan.c - MPI functions
2 * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
3 *
4 * This file is part of GnuPG.
5 *
6 * GnuPG is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22#include "longlong.h"
23
24/****************
25 * Scan through an mpi and return byte for byte. a -1 is returned to indicate
26 * the end of the mpi. Scanning is done from the lsb to the msb, returned
27 * values are in the range of 0 .. 255.
28 *
29 * FIXME: This code is VERY ugly!
30 */
31int mpi_getbyte(const MPI a, unsigned idx)
32{
33 int i, j;
34 unsigned n;
35 mpi_ptr_t ap;
36 mpi_limb_t limb;
37
38 ap = a->d;
39 for (n = 0, i = 0; i < a->nlimbs; i++) {
40 limb = ap[i];
41 for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++)
42 if (n == idx)
43 return (limb >> j * 8) & 0xff;
44 }
45 return -1;
46}
47
48/****************
49 * Put a value at position IDX into A. idx counts from lsb to msb
50 */
51void mpi_putbyte(MPI a, unsigned idx, int xc)
52{
53 int i, j;
54 unsigned n;
55 mpi_ptr_t ap;
56 mpi_limb_t limb, c;
57
58 c = xc & 0xff;
59 ap = a->d;
60 for (n = 0, i = 0; i < a->alloced; i++) {
61 limb = ap[i];
62 for (j = 0; j < BYTES_PER_MPI_LIMB; j++, n++)
63 if (n == idx) {
64#if BYTES_PER_MPI_LIMB == 4
65 if (j == 0)
66 limb = (limb & 0xffffff00) | c;
67 else if (j == 1)
68 limb = (limb & 0xffff00ff) | (c << 8);
69 else if (j == 2)
70 limb = (limb & 0xff00ffff) | (c << 16);
71 else
72 limb = (limb & 0x00ffffff) | (c << 24);
73#elif BYTES_PER_MPI_LIMB == 8
74 if (j == 0)
75 limb = (limb & 0xffffffffffffff00) | c;
76 else if (j == 1)
77 limb =
78 (limb & 0xffffffffffff00ff) | (c <<
79 8);
80 else if (j == 2)
81 limb =
82 (limb & 0xffffffffff00ffff) | (c <<
83 16);
84 else if (j == 3)
85 limb =
86 (limb & 0xffffffff00ffffff) | (c <<
87 24);
88 else if (j == 4)
89 limb =
90 (limb & 0xffffff00ffffffff) | (c <<
91 32);
92 else if (j == 5)
93 limb =
94 (limb & 0xffff00ffffffffff) | (c <<
95 40);
96 else if (j == 6)
97 limb =
98 (limb & 0xff00ffffffffffff) | (c <<
99 48);
100 else
101 limb =
102 (limb & 0x00ffffffffffffff) | (c <<
103 56);
104#else
105#error please enhance this function, its ugly - i know.
106#endif
107 if (a->nlimbs <= i)
108 a->nlimbs = i + 1;
109 ap[i] = limb;
110 return;
111 }
112 }
113 log_bug("index out of range\n");
114}
115
116/****************
117 * Count the number of zerobits at the low end of A
118 */
119unsigned mpi_trailing_zeros(const MPI a)
120{
121 unsigned n, count = 0;
122
123 for (n = 0; n < a->nlimbs; n++) {
124 if (a->d[n]) {
125 unsigned nn;
126 mpi_limb_t alimb = a->d[n];
127
128 count_trailing_zeros(nn, alimb);
129 count += nn;
130 break;
131 }
132 count += BITS_PER_MPI_LIMB;
133 }
134 return count;
135
136}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-02 12:18:29 -0500