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Diffstat (limited to 'lib/mpi/mpiutil.c')
| -rw-r--r-- | lib/mpi/mpiutil.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c new file mode 100644 index 000000000000..eefc55d6b7f5 --- /dev/null +++ b/lib/mpi/mpiutil.c @@ -0,0 +1,208 @@ +/* mpiutil.ac - Utility functions for MPI + * 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" + +/**************** + * Note: It was a bad idea to use the number of limbs to allocate + * because on a alpha the limbs are large but we normally need + * integers of n bits - So we should chnage this to bits (or bytes). + * + * But mpi_alloc is used in a lot of places :-) + */ +MPI mpi_alloc(unsigned nlimbs) +{ + MPI a; + + a = kmalloc(sizeof *a, GFP_KERNEL); + if (!a) + return a; + + if (nlimbs) { + a->d = mpi_alloc_limb_space(nlimbs); + if (!a->d) { + kfree(a); + return NULL; + } + } else { + a->d = NULL; + } + + a->alloced = nlimbs; + a->nlimbs = 0; + a->sign = 0; + a->flags = 0; + a->nbits = 0; + return a; +} +EXPORT_SYMBOL_GPL(mpi_alloc); + +mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs) +{ + size_t len = nlimbs * sizeof(mpi_limb_t); + + return kmalloc(len, GFP_KERNEL); +} + +void mpi_free_limb_space(mpi_ptr_t a) +{ + if (!a) + return; + + kfree(a); +} + +void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs) +{ + mpi_free_limb_space(a->d); + a->d = ap; + a->alloced = nlimbs; +} + +/**************** + * Resize the array of A to NLIMBS. the additional space is cleared + * (set to 0) [done by m_realloc()] + */ +int mpi_resize(MPI a, unsigned nlimbs) +{ + void *p; + + if (nlimbs <= a->alloced) + return 0; /* no need to do it */ + + if (a->d) { + p = kmalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL); + if (!p) + return -ENOMEM; + memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t)); + kfree(a->d); + a->d = p; + } else { + a->d = kzalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL); + if (!a->d) + return -ENOMEM; + } + a->alloced = nlimbs; + return 0; +} + +void mpi_clear(MPI a) +{ + a->nlimbs = 0; + a->nbits = 0; + a->flags = 0; +} + +void mpi_free(MPI a) +{ + if (!a) + return; + + if (a->flags & 4) + kfree(a->d); + else + mpi_free_limb_space(a->d); + + if (a->flags & ~7) + pr_info("invalid flag value in mpi\n"); + kfree(a); +} +EXPORT_SYMBOL_GPL(mpi_free); + +/**************** + * Note: This copy function should not interpret the MPI + * but copy it transparently. + */ +int mpi_copy(MPI *copied, const MPI a) +{ + size_t i; + MPI b; + + *copied = MPI_NULL; + + if (a) { + b = mpi_alloc(a->nlimbs); + if (!b) + return -ENOMEM; + + b->nlimbs = a->nlimbs; + b->sign = a->sign; + b->flags = a->flags; + b->nbits = a->nbits; + + for (i = 0; i < b->nlimbs; i++) + b->d[i] = a->d[i]; + + *copied = b; + } + + return 0; +} + +int mpi_set(MPI w, const MPI u) +{ + mpi_ptr_t wp, up; + mpi_size_t usize = u->nlimbs; + int usign = u->sign; + + if (RESIZE_IF_NEEDED(w, (size_t) usize) < 0) + return -ENOMEM; + + wp = w->d; + up = u->d; + MPN_COPY(wp, up, usize); + w->nlimbs = usize; + w->nbits = u->nbits; + w->flags = u->flags; + w->sign = usign; + return 0; +} + +int mpi_set_ui(MPI w, unsigned long u) +{ + if (RESIZE_IF_NEEDED(w, 1) < 0) + return -ENOMEM; + w->d[0] = u; + w->nlimbs = u ? 1 : 0; + w->sign = 0; + w->nbits = 0; + w->flags = 0; + return 0; +} + +MPI mpi_alloc_set_ui(unsigned long u) +{ + MPI w = mpi_alloc(1); + if (!w) + return w; + w->d[0] = u; + w->nlimbs = u ? 1 : 0; + w->sign = 0; + return w; +} + +void mpi_swap(MPI a, MPI b) +{ + struct gcry_mpi tmp; + + tmp = *a; + *a = *b; + *b = tmp; +} |