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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 20:11:12 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 20:11:12 +0300
commitccc9d4a6d640cbde05d519edeb727881646cf71b (patch)
tree736c90b100703501d5e3fa3eccc57a48f70bef14 /lib/mpi/mpicoder.c
parent66ef3493d4bb387f5a83915e33dc893102fd1b43 (diff)
parent271817a3e92c0455bda5856d87eca244ad67d3a2 (diff)
downloadlinux-ccc9d4a6d640cbde05d519edeb727881646cf71b.tar.xz
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu: "API: - Add support for cipher output IVs in testmgr - Add missing crypto_ahash_blocksize helper - Mark authenc and des ciphers as not allowed under FIPS. Algorithms: - Add CRC support to 842 compression - Add keywrap algorithm - A number of changes to the akcipher interface: + Separate functions for setting public/private keys. + Use SG lists. Drivers: - Add Intel SHA Extension optimised SHA1 and SHA256 - Use dma_map_sg instead of custom functions in crypto drivers - Add support for STM32 RNG - Add support for ST RNG - Add Device Tree support to exynos RNG driver - Add support for mxs-dcp crypto device on MX6SL - Add xts(aes) support to caam - Add ctr(aes) and xts(aes) support to qat - A large set of fixes from Russell King for the marvell/cesa driver" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (115 commits) crypto: asymmetric_keys - Fix unaligned access in x509_get_sig_params() crypto: akcipher - Don't #include crypto/public_key.h as the contents aren't used hwrng: exynos - Add Device Tree support hwrng: exynos - Fix missing configuration after suspend to RAM hwrng: exynos - Add timeout for waiting on init done dt-bindings: rng: Describe Exynos4 PRNG bindings crypto: marvell/cesa - use __le32 for hardware descriptors crypto: marvell/cesa - fix missing cpu_to_le32() in mv_cesa_dma_add_op() crypto: marvell/cesa - use memcpy_fromio()/memcpy_toio() crypto: marvell/cesa - use gfp_t for gfp flags crypto: marvell/cesa - use dma_addr_t for cur_dma crypto: marvell/cesa - use readl_relaxed()/writel_relaxed() crypto: caam - fix indentation of close braces crypto: caam - only export the state we really need to export crypto: caam - fix non-block aligned hash calculation crypto: caam - avoid needlessly saving and restoring caam_hash_ctx crypto: caam - print errno code when hash registration fails crypto: marvell/cesa - fix memory leak crypto: marvell/cesa - fix first-fragment handling in mv_cesa_ahash_dma_last_req() crypto: marvell/cesa - rearrange handling for sw padded hashes ...
Diffstat (limited to 'lib/mpi/mpicoder.c')
-rw-r--r--lib/mpi/mpicoder.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 95c52a95259e..c7e0a705eecf 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -319,3 +319,202 @@ int mpi_set_buffer(MPI a, const void *xbuffer, unsigned nbytes, int sign)
return 0;
}
EXPORT_SYMBOL_GPL(mpi_set_buffer);
+
+/**
+ * mpi_write_to_sgl() - Funnction exports MPI to an sgl (msb first)
+ *
+ * This function works in the same way as the mpi_read_buffer, but it
+ * takes an sgl instead of u8 * buf.
+ *
+ * @a: a multi precision integer
+ * @sgl: scatterlist to write to. Needs to be at least
+ * mpi_get_size(a) long.
+ * @nbytes: in/out param - it has the be set to the maximum number of
+ * bytes that can be written to sgl. This has to be at least
+ * the size of the integer a. On return it 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
+ */
+int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
+ int *sign)
+{
+ u8 *p, *p2;
+ mpi_limb_t alimb, alimb2;
+ unsigned int n = mpi_get_size(a);
+ int i, x, y = 0, lzeros = 0, buf_len;
+
+ if (!nbytes || *nbytes < n)
+ return -EINVAL;
+
+ if (sign)
+ *sign = a->sign;
+
+ p = (void *)&a->d[a->nlimbs] - 1;
+
+ for (i = a->nlimbs * sizeof(alimb) - 1; i >= 0; i--, p--) {
+ if (!*p)
+ lzeros++;
+ else
+ break;
+ }
+
+ *nbytes = n - lzeros;
+ buf_len = sgl->length;
+ p2 = sg_virt(sgl);
+
+ for (i = a->nlimbs - 1; i >= 0; i--) {
+ alimb = a->d[i];
+ p = (u8 *)&alimb2;
+#if BYTES_PER_MPI_LIMB == 4
+ *p++ = alimb >> 24;
+ *p++ = alimb >> 16;
+ *p++ = alimb >> 8;
+ *p++ = alimb;
+#elif BYTES_PER_MPI_LIMB == 8
+ *p++ = alimb >> 56;
+ *p++ = alimb >> 48;
+ *p++ = alimb >> 40;
+ *p++ = alimb >> 32;
+ *p++ = alimb >> 24;
+ *p++ = alimb >> 16;
+ *p++ = alimb >> 8;
+ *p++ = alimb;
+#else
+#error please implement for this limb size.
+#endif
+ if (lzeros > 0) {
+ if (lzeros >= sizeof(alimb)) {
+ p -= sizeof(alimb);
+ continue;
+ } else {
+ mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
+ mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
+ + lzeros;
+ *limb1 = *limb2;
+ p -= lzeros;
+ y = lzeros;
+ }
+ lzeros -= sizeof(alimb);
+ }
+
+ p = p - (sizeof(alimb) - y);
+
+ for (x = 0; x < sizeof(alimb) - y; x++) {
+ if (!buf_len) {
+ sgl = sg_next(sgl);
+ if (!sgl)
+ return -EINVAL;
+ buf_len = sgl->length;
+ p2 = sg_virt(sgl);
+ }
+ *p2++ = *p++;
+ buf_len--;
+ }
+ y = 0;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_write_to_sgl);
+
+/*
+ * mpi_read_raw_from_sgl() - Function allocates an MPI and populates it with
+ * data from the sgl
+ *
+ * This function works in the same way as the mpi_read_raw_data, but it
+ * takes an sgl instead of void * buffer. i.e. it allocates
+ * a new MPI and reads the content of the sgl to the MPI.
+ *
+ * @sgl: scatterlist to read from
+ * @len: number of bytes to read
+ *
+ * Return: Pointer to a new MPI or NULL on error
+ */
+MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int len)
+{
+ struct scatterlist *sg;
+ int x, i, j, z, lzeros, ents;
+ unsigned int nbits, nlimbs, nbytes;
+ mpi_limb_t a;
+ MPI val = NULL;
+
+ lzeros = 0;
+ ents = sg_nents(sgl);
+
+ for_each_sg(sgl, sg, ents, i) {
+ const u8 *buff = sg_virt(sg);
+ int len = sg->length;
+
+ while (len && !*buff) {
+ lzeros++;
+ len--;
+ buff++;
+ }
+
+ if (len && *buff)
+ break;
+
+ ents--;
+ lzeros = 0;
+ }
+
+ sgl = sg;
+
+ if (!ents)
+ nbytes = 0;
+ else
+ nbytes = len - lzeros;
+
+ nbits = nbytes * 8;
+ if (nbits > MAX_EXTERN_MPI_BITS) {
+ pr_info("MPI: mpi too large (%u bits)\n", nbits);
+ return NULL;
+ }
+
+ if (nbytes > 0)
+ nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros));
+ else
+ nbits = 0;
+
+ nlimbs = DIV_ROUND_UP(nbytes, BYTES_PER_MPI_LIMB);
+ val = mpi_alloc(nlimbs);
+ if (!val)
+ return NULL;
+
+ val->nbits = nbits;
+ val->sign = 0;
+ val->nlimbs = nlimbs;
+
+ if (nbytes == 0)
+ return val;
+
+ j = nlimbs - 1;
+ a = 0;
+ z = 0;
+ x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
+ x %= BYTES_PER_MPI_LIMB;
+
+ for_each_sg(sgl, sg, ents, i) {
+ const u8 *buffer = sg_virt(sg) + lzeros;
+ int len = sg->length - lzeros;
+ int buf_shift = x;
+
+ if (sg_is_last(sg) && (len % BYTES_PER_MPI_LIMB))
+ len += BYTES_PER_MPI_LIMB - (len % BYTES_PER_MPI_LIMB);
+
+ for (; x < len + buf_shift; x++) {
+ a <<= 8;
+ a |= *buffer++;
+ if (((z + x + 1) % BYTES_PER_MPI_LIMB) == 0) {
+ val->d[j--] = a;
+ a = 0;
+ }
+ }
+ z += x;
+ x = 0;
+ lzeros = 0;
+ }
+ return val;
+}
+EXPORT_SYMBOL_GPL(mpi_read_raw_from_sgl);