diff options
Diffstat (limited to 'lib/crypto/mpi/mpi-bit.c')
| -rw-r--r-- | lib/crypto/mpi/mpi-bit.c | 168 |
1 files changed, 18 insertions, 150 deletions
diff --git a/lib/crypto/mpi/mpi-bit.c b/lib/crypto/mpi/mpi-bit.c index e08fc202ea5c..835a2f0622a0 100644 --- a/lib/crypto/mpi/mpi-bit.c +++ b/lib/crypto/mpi/mpi-bit.c @@ -32,7 +32,6 @@ void mpi_normalize(MPI a) for (; a->nlimbs && !a->d[a->nlimbs - 1]; a->nlimbs--) ; } -EXPORT_SYMBOL_GPL(mpi_normalize); /**************** * Return the number of bits in A. @@ -77,9 +76,10 @@ EXPORT_SYMBOL_GPL(mpi_test_bit); /**************** * Set bit N of A. */ -void mpi_set_bit(MPI a, unsigned int n) +int mpi_set_bit(MPI a, unsigned int n) { unsigned int i, limbno, bitno; + int err; limbno = n / BITS_PER_MPI_LIMB; bitno = n % BITS_PER_MPI_LIMB; @@ -87,106 +87,31 @@ void mpi_set_bit(MPI a, unsigned int n) if (limbno >= a->nlimbs) { for (i = a->nlimbs; i < a->alloced; i++) a->d[i] = 0; - mpi_resize(a, limbno+1); + err = mpi_resize(a, limbno+1); + if (err) + return err; a->nlimbs = limbno+1; } a->d[limbno] |= (A_LIMB_1<<bitno); -} - -/**************** - * Set bit N of A. and clear all bits above - */ -void mpi_set_highbit(MPI a, unsigned int n) -{ - unsigned int i, limbno, bitno; - - limbno = n / BITS_PER_MPI_LIMB; - bitno = n % BITS_PER_MPI_LIMB; - - if (limbno >= a->nlimbs) { - for (i = a->nlimbs; i < a->alloced; i++) - a->d[i] = 0; - mpi_resize(a, limbno+1); - a->nlimbs = limbno+1; - } - a->d[limbno] |= (A_LIMB_1<<bitno); - for (bitno++; bitno < BITS_PER_MPI_LIMB; bitno++) - a->d[limbno] &= ~(A_LIMB_1 << bitno); - a->nlimbs = limbno+1; -} -EXPORT_SYMBOL_GPL(mpi_set_highbit); - -/**************** - * clear bit N of A and all bits above - */ -void mpi_clear_highbit(MPI a, unsigned int n) -{ - unsigned int limbno, bitno; - - limbno = n / BITS_PER_MPI_LIMB; - bitno = n % BITS_PER_MPI_LIMB; - - if (limbno >= a->nlimbs) - return; /* not allocated, therefore no need to clear bits :-) */ - - for ( ; bitno < BITS_PER_MPI_LIMB; bitno++) - a->d[limbno] &= ~(A_LIMB_1 << bitno); - a->nlimbs = limbno+1; -} - -/**************** - * Clear bit N of A. - */ -void mpi_clear_bit(MPI a, unsigned int n) -{ - unsigned int limbno, bitno; - - limbno = n / BITS_PER_MPI_LIMB; - bitno = n % BITS_PER_MPI_LIMB; - - if (limbno >= a->nlimbs) - return; /* Don't need to clear this bit, it's far too left. */ - a->d[limbno] &= ~(A_LIMB_1 << bitno); -} -EXPORT_SYMBOL_GPL(mpi_clear_bit); - - -/**************** - * Shift A by COUNT limbs to the right - * This is used only within the MPI library - */ -void mpi_rshift_limbs(MPI a, unsigned int count) -{ - mpi_ptr_t ap = a->d; - mpi_size_t n = a->nlimbs; - unsigned int i; - - if (count >= n) { - a->nlimbs = 0; - return; - } - - for (i = 0; i < n - count; i++) - ap[i] = ap[i+count]; - ap[i] = 0; - a->nlimbs -= count; + return 0; } /* * Shift A by N bits to the right. */ -void mpi_rshift(MPI x, MPI a, unsigned int n) +int mpi_rshift(MPI x, MPI a, unsigned int n) { mpi_size_t xsize; unsigned int i; unsigned int nlimbs = (n/BITS_PER_MPI_LIMB); unsigned int nbits = (n%BITS_PER_MPI_LIMB); + int err; if (x == a) { /* In-place operation. */ if (nlimbs >= x->nlimbs) { x->nlimbs = 0; - return; + return 0; } if (nlimbs) { @@ -201,7 +126,9 @@ void mpi_rshift(MPI x, MPI a, unsigned int n) /* Copy and shift by more or equal bits than in a limb. */ xsize = a->nlimbs; x->sign = a->sign; - RESIZE_IF_NEEDED(x, xsize); + err = RESIZE_IF_NEEDED(x, xsize); + if (err) + return err; x->nlimbs = xsize; for (i = 0; i < a->nlimbs; i++) x->d[i] = a->d[i]; @@ -209,7 +136,7 @@ void mpi_rshift(MPI x, MPI a, unsigned int n) if (nlimbs >= x->nlimbs) { x->nlimbs = 0; - return; + return 0; } for (i = 0; i < x->nlimbs - nlimbs; i++) @@ -223,7 +150,9 @@ void mpi_rshift(MPI x, MPI a, unsigned int n) /* Copy and shift by less than bits in a limb. */ xsize = a->nlimbs; x->sign = a->sign; - RESIZE_IF_NEEDED(x, xsize); + err = RESIZE_IF_NEEDED(x, xsize); + if (err) + return err; x->nlimbs = xsize; if (xsize) { @@ -239,68 +168,7 @@ void mpi_rshift(MPI x, MPI a, unsigned int n) } } MPN_NORMALIZE(x->d, x->nlimbs); -} -EXPORT_SYMBOL_GPL(mpi_rshift); - -/**************** - * Shift A by COUNT limbs to the left - * This is used only within the MPI library - */ -void mpi_lshift_limbs(MPI a, unsigned int count) -{ - mpi_ptr_t ap; - int n = a->nlimbs; - int i; - if (!count || !n) - return; - - RESIZE_IF_NEEDED(a, n+count); - - ap = a->d; - for (i = n-1; i >= 0; i--) - ap[i+count] = ap[i]; - for (i = 0; i < count; i++) - ap[i] = 0; - a->nlimbs += count; -} - -/* - * Shift A by N bits to the left. - */ -void mpi_lshift(MPI x, MPI a, unsigned int n) -{ - unsigned int nlimbs = (n/BITS_PER_MPI_LIMB); - unsigned int nbits = (n%BITS_PER_MPI_LIMB); - - if (x == a && !n) - return; /* In-place shift with an amount of zero. */ - - if (x != a) { - /* Copy A to X. */ - unsigned int alimbs = a->nlimbs; - int asign = a->sign; - mpi_ptr_t xp, ap; - - RESIZE_IF_NEEDED(x, alimbs+nlimbs+1); - xp = x->d; - ap = a->d; - MPN_COPY(xp, ap, alimbs); - x->nlimbs = alimbs; - x->flags = a->flags; - x->sign = asign; - } - - if (nlimbs && !nbits) { - /* Shift a full number of limbs. */ - mpi_lshift_limbs(x, nlimbs); - } else if (n) { - /* We use a very dump approach: Shift left by the number of - * limbs plus one and than fix it up by an rshift. - */ - mpi_lshift_limbs(x, nlimbs+1); - mpi_rshift(x, x, BITS_PER_MPI_LIMB - nbits); - } - - MPN_NORMALIZE(x->d, x->nlimbs); + return 0; } +EXPORT_SYMBOL_GPL(mpi_rshift); |