diff options
Diffstat (limited to 'lib/mpi')
| -rw-r--r-- | lib/mpi/longlong.h | 4 | ||||
| -rw-r--r-- | lib/mpi/mpicoder.c | 107 | ||||
| -rw-r--r-- | lib/mpi/mpiutil.c | 6 |
3 files changed, 89 insertions, 28 deletions
diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h index aac511417ad1..a89d041592c8 100644 --- a/lib/mpi/longlong.h +++ b/lib/mpi/longlong.h @@ -639,7 +639,7 @@ do { \ ************** MIPS ***************** ***************************************/ #if defined(__mips__) && W_TYPE_SIZE == 32 -#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#if (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4) #define umul_ppmm(w1, w0, u, v) \ do { \ UDItype __ll = (UDItype)(u) * (v); \ @@ -671,7 +671,7 @@ do { \ ************** MIPS/64 ************** ***************************************/ #if (defined(__mips) && __mips >= 3) && W_TYPE_SIZE == 64 -#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#if (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4) #define umul_ppmm(w1, w0, u, v) \ do { \ typedef unsigned int __ll_UTItype __attribute__((mode(TI))); \ diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c index 4cc6442733f4..95c52a95259e 100644 --- a/lib/mpi/mpicoder.c +++ b/lib/mpi/mpicoder.c @@ -128,28 +128,43 @@ leave: } EXPORT_SYMBOL_GPL(mpi_read_from_buffer); -/**************** - * Return an allocated buffer with the MPI (msb first). - * NBYTES receives the length of this buffer. Caller must free the - * return string (This function does return a 0 byte buffer with NBYTES - * set to zero if the value of A is zero. If sign is not NULL, it will - * be set to the sign of the A. +/** + * mpi_read_buffer() - read MPI to a bufer provided by user (msb first) + * + * @a: a multi precision integer + * @buf: bufer to which the output will be written to. Needs to be at + * leaset mpi_get_size(a) long. + * @buf_len: size of the buf. + * @nbytes: receives the actual length of the data written. + * @sign: if not NULL, it will be set to the sign of a. + * + * Return: 0 on success or error code in case of error */ -void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign) +int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes, + int *sign) { - uint8_t *p, *buffer; + uint8_t *p; mpi_limb_t alimb; - int i; - unsigned int n; + unsigned int n = mpi_get_size(a); + int i, lzeros = 0; + + if (buf_len < n || !buf || !nbytes) + return -EINVAL; if (sign) *sign = a->sign; - *nbytes = n = a->nlimbs * BYTES_PER_MPI_LIMB; - if (!n) - n++; /* avoid zero length allocation */ - p = buffer = kmalloc(n, GFP_KERNEL); - if (!p) - return NULL; + + p = (void *)&a->d[a->nlimbs] - 1; + + for (i = a->nlimbs * sizeof(alimb) - 1; i >= 0; i--, p--) { + if (!*p) + lzeros++; + else + break; + } + + p = buf; + *nbytes = n - lzeros; for (i = a->nlimbs - 1; i >= 0; i--) { alimb = a->d[i]; @@ -170,16 +185,62 @@ void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign) #else #error please implement for this limb size. #endif + + if (lzeros > 0) { + if (lzeros >= sizeof(alimb)) { + p -= sizeof(alimb); + } else { + mpi_limb_t *limb1 = (void *)p - sizeof(alimb); + mpi_limb_t *limb2 = (void *)p - sizeof(alimb) + + lzeros; + *limb1 = *limb2; + p -= lzeros; + } + lzeros -= sizeof(alimb); + } } + return 0; +} +EXPORT_SYMBOL_GPL(mpi_read_buffer); + +/* + * mpi_get_buffer() - Returns an allocated buffer with the MPI (msb first). + * Caller must free the return string. + * This function does return a 0 byte buffer with nbytes set to zero if the + * value of A is zero. + * + * @a: a multi precision integer. + * @nbytes: receives the length of this buffer. + * @sign: if not NULL, it will be set to the sign of the a. + * + * Return: Pointer to MPI buffer or NULL on error + */ +void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign) +{ + uint8_t *buf; + unsigned int n; + int ret; + + if (!nbytes) + return NULL; + + n = mpi_get_size(a); - /* this is sub-optimal but we need to do the shift operation - * because the caller has to free the returned buffer */ - for (p = buffer; !*p && *nbytes; p++, --*nbytes) - ; - if (p != buffer) - memmove(buffer, p, *nbytes); + if (!n) + n++; - return buffer; + buf = kmalloc(n, GFP_KERNEL); + + if (!buf) + return NULL; + + ret = mpi_read_buffer(a, buf, n, nbytes, sign); + + if (ret) { + kfree(buf); + return NULL; + } + return buf; } EXPORT_SYMBOL_GPL(mpi_get_buffer); diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c index bf076d281d40..314f4dfa603e 100644 --- a/lib/mpi/mpiutil.c +++ b/lib/mpi/mpiutil.c @@ -69,7 +69,7 @@ void mpi_free_limb_space(mpi_ptr_t a) if (!a) return; - kfree(a); + kzfree(a); } void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs) @@ -95,7 +95,7 @@ int mpi_resize(MPI a, unsigned nlimbs) if (!p) return -ENOMEM; memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t)); - kfree(a->d); + kzfree(a->d); a->d = p; } else { a->d = kzalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL); @@ -112,7 +112,7 @@ void mpi_free(MPI a) return; if (a->flags & 4) - kfree(a->d); + kzfree(a->d); else mpi_free_limb_space(a->d); |