diff options
Diffstat (limited to 'lib/crypto/mpi/mpi-div.c')
| -rw-r--r-- | lib/crypto/mpi/mpi-div.c | 55 |
1 files changed, 40 insertions, 15 deletions
diff --git a/lib/crypto/mpi/mpi-div.c b/lib/crypto/mpi/mpi-div.c index 2ff0ebd74fd7..6e5044e72595 100644 --- a/lib/crypto/mpi/mpi-div.c +++ b/lib/crypto/mpi/mpi-div.c @@ -14,12 +14,13 @@ #include "mpi-internal.h" #include "longlong.h" -void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den); +int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den); -void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor) +int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor) { int divisor_sign = divisor->sign; MPI temp_divisor = NULL; + int err; /* 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 @@ -27,16 +28,22 @@ void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor) */ if (rem == divisor) { temp_divisor = mpi_copy(divisor); + if (!temp_divisor) + return -ENOMEM; divisor = temp_divisor; } - mpi_tdiv_r(rem, dividend, divisor); + err = mpi_tdiv_r(rem, dividend, divisor); + if (err) + goto free_temp_divisor; if (((divisor_sign?1:0) ^ (dividend->sign?1:0)) && rem->nlimbs) - mpi_add(rem, rem, divisor); + err = mpi_add(rem, rem, divisor); - if (temp_divisor) - mpi_free(temp_divisor); +free_temp_divisor: + mpi_free(temp_divisor); + + return err; } /* If den == quot, den needs temporary storage. @@ -46,12 +53,12 @@ void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor) * i.e no extra storage should be allocated. */ -void mpi_tdiv_r(MPI rem, MPI num, MPI den) +int mpi_tdiv_r(MPI rem, MPI num, MPI den) { - mpi_tdiv_qr(NULL, rem, num, den); + return mpi_tdiv_qr(NULL, rem, num, den); } -void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) +int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) { mpi_ptr_t np, dp; mpi_ptr_t qp, rp; @@ -64,13 +71,16 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) mpi_limb_t q_limb; mpi_ptr_t marker[5]; int markidx = 0; + int err; /* 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; - mpi_resize(rem, rsize); + err = mpi_resize(rem, rsize); + if (err) + return err; qsize = rsize - dsize; /* qsize cannot be bigger than this. */ if (qsize <= 0) { @@ -86,11 +96,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) quot->nlimbs = 0; quot->sign = 0; } - return; + return 0; } - if (quot) - mpi_resize(quot, qsize); + if (quot) { + err = mpi_resize(quot, qsize); + if (err) + return err; + } /* Read pointers here, when reallocation is finished. */ np = num->d; @@ -112,10 +125,10 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) rsize = rlimb != 0?1:0; rem->nlimbs = rsize; rem->sign = sign_remainder; - return; + return 0; } - + err = -ENOMEM; if (quot) { qp = quot->d; /* Make sure QP and NP point to different objects. Otherwise the @@ -123,6 +136,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) */ if (qp == np) { /* Copy NP object to temporary space. */ np = marker[markidx++] = mpi_alloc_limb_space(nsize); + if (!np) + goto out_free_marker; MPN_COPY(np, qp, nsize); } } else /* Put quotient at top of remainder. */ @@ -143,6 +158,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) * the original contents of the denominator. */ tp = marker[markidx++] = mpi_alloc_limb_space(dsize); + if (!tp) + goto out_free_marker; mpihelp_lshift(tp, dp, dsize, normalization_steps); dp = tp; @@ -164,6 +181,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) mpi_ptr_t tp; tp = marker[markidx++] = mpi_alloc_limb_space(dsize); + if (!tp) + goto out_free_marker; MPN_COPY(tp, dp, dsize); dp = tp; } @@ -198,8 +217,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den) rem->nlimbs = rsize; rem->sign = sign_remainder; + + err = 0; + +out_free_marker: while (markidx) { markidx--; mpi_free_limb_space(marker[markidx]); } + + return err; } |