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authorLinus Torvalds <torvalds@linux-foundation.org>2023-08-29 11:23:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2023-08-29 11:23:29 -0700
commit68cf01760bc0891074e813b9bb06d2696cac1c01 (patch)
tree0bfbd6a995c19df689476782450a7df8bd51b213 /lib/crypto/mpi/mpi-add.c
parentf97e18a3f2fb78a4ed0d25e427535d9f853b9e9e (diff)
parent85b9bf9a514d991fcecb118d0a8a35e754ff9265 (diff)
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Merge tag 'v6.6-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "API: - Move crypto engine callback from tfm ctx into algorithm object - Fix atomic sleep bug in crypto_destroy_instance - Move lib/mpi into lib/crypto Algorithms: - Add chacha20 and poly1305 implementation for powerpc p10 Drivers: - Add AES skcipher and aead support to starfive - Add Dynamic Boost Control support to ccp - Add support for STM32P13 platform to stm32" * tag 'v6.6-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (149 commits) Revert "dt-bindings: crypto: qcom,prng: Add SM8450" crypto: chelsio - Remove unused declarations X.509: if signature is unsupported skip validation crypto: qat - fix crypto capability detection for 4xxx crypto: drivers - Explicitly include correct DT includes crypto: engine - Remove crypto_engine_ctx crypto: zynqmp - Use new crypto_engine_op interface crypto: virtio - Use new crypto_engine_op interface crypto: stm32 - Use new crypto_engine_op interface crypto: jh7110 - Use new crypto_engine_op interface crypto: rk3288 - Use new crypto_engine_op interface crypto: omap - Use new crypto_engine_op interface crypto: keembay - Use new crypto_engine_op interface crypto: sl3516 - Use new crypto_engine_op interface crypto: caam - Use new crypto_engine_op interface crypto: aspeed - Remove non-standard sha512 algorithms crypto: aspeed - Use new crypto_engine_op interface crypto: amlogic - Use new crypto_engine_op interface crypto: sun8i-ss - Use new crypto_engine_op interface crypto: sun8i-ce - Use new crypto_engine_op interface ...
Diffstat (limited to 'lib/crypto/mpi/mpi-add.c')
-rw-r--r--lib/crypto/mpi/mpi-add.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/lib/crypto/mpi/mpi-add.c b/lib/crypto/mpi/mpi-add.c
new file mode 100644
index 000000000000..9056fc5167fc
--- /dev/null
+++ b/lib/crypto/mpi/mpi-add.c
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+/* mpi-add.c - MPI functions
+ * Copyright (C) 1994, 1996, 1998, 2001, 2002,
+ * 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * 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.
+ */
+
+#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.
+ */
+void mpi_add_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)
+ mpi_resize(w, wsize);
+
+ /* 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;
+}
+
+
+void 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;
+ 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;
+ }
+ 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;
+}
+EXPORT_SYMBOL_GPL(mpi_add);
+
+void mpi_sub(MPI w, MPI u, MPI v)
+{
+ MPI vv = mpi_copy(v);
+ vv->sign = !vv->sign;
+ mpi_add(w, u, vv);
+ mpi_free(vv);
+}
+EXPORT_SYMBOL_GPL(mpi_sub);
+
+void mpi_addm(MPI w, MPI u, MPI v, MPI m)
+{
+ mpi_add(w, u, v);
+ mpi_mod(w, w, m);
+}
+EXPORT_SYMBOL_GPL(mpi_addm);
+
+void mpi_subm(MPI w, MPI u, MPI v, MPI m)
+{
+ mpi_sub(w, u, v);
+ mpi_mod(w, w, m);
+}
+EXPORT_SYMBOL_GPL(mpi_subm);