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-rw-r--r--crypto/userspace/utils.c298
1 files changed, 298 insertions, 0 deletions
diff --git a/crypto/userspace/utils.c b/crypto/userspace/utils.c
new file mode 100644
index 00000000000..a427833fdad
--- /dev/null
+++ b/crypto/userspace/utils.c
@@ -0,0 +1,298 @@
+/*
+ * New driver for /dev/crypto device (aka CryptoDev)
+ *
+ * Copyright (c) 2010 Red Hat Inc.
+ *
+ * This program 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.
+ *
+ * This program 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ *
+ * Red Hat Author: Miloslav Trmač
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <net/netlink.h>
+#include "ncr-int.h"
+#include "utils.h"
+
+#ifdef CONFIG_COMPAT
+/* max() is too clever for compile-time constants */
+#define CONST_MAX(A, B) ((A) > (B) ? (A) : (B))
+
+#define MAX_SESSION_INPUT_DATA_SIZE \
+ (CONST_MAX(sizeof(struct ncr_session_input_data), \
+ sizeof(struct compat_ncr_session_input_data)))
+#define MAX_SESSION_OUTPUT_BUFFER_SIZE \
+ (CONST_MAX(sizeof(struct ncr_session_output_buffer), \
+ sizeof(struct compat_ncr_session_output_buffer)))
+
+#else /* !CONFIG_COMPAT */
+
+#define MAX_SESSION_INPUT_DATA_SIZE (sizeof(struct ncr_session_input_data))
+#define MAX_SESSION_OUTPUT_BUFFER_SIZE \
+ (sizeof(struct ncr_session_output_buffer))
+
+#endif /* !CONFIG_COMPAT */
+
+static const struct nla_policy ncr_attr_policy[NCR_ATTR_MAX + 1] = {
+ [NCR_ATTR_ALGORITHM] = { NLA_NUL_STRING, 0 },
+ [NCR_ATTR_DERIVATION_ALGORITHM] = { NLA_NUL_STRING, 0 },
+ [NCR_ATTR_SIGNATURE_HASH_ALGORITHM] = { NLA_NUL_STRING, 0 },
+ [NCR_ATTR_WRAPPING_ALGORITHM] = { NLA_NUL_STRING, 0 },
+ [NCR_ATTR_UPDATE_INPUT_DATA] = {
+ NLA_BINARY, MAX_SESSION_INPUT_DATA_SIZE
+ },
+ [NCR_ATTR_UPDATE_OUTPUT_BUFFER] = {
+ NLA_BINARY, MAX_SESSION_OUTPUT_BUFFER_SIZE
+ },
+ [NCR_ATTR_UPDATE_INPUT_KEY_AS_DATA] = { NLA_U32, 0 },
+ [NCR_ATTR_FINAL_INPUT_DATA] = {
+ NLA_BINARY, MAX_SESSION_INPUT_DATA_SIZE
+ },
+ [NCR_ATTR_FINAL_OUTPUT_BUFFER] = {
+ NLA_BINARY, MAX_SESSION_OUTPUT_BUFFER_SIZE
+ },
+ [NCR_ATTR_KEY] = { NLA_U32, 0 },
+ [NCR_ATTR_KEY_FLAGS] = { NLA_U32, 0 },
+ [NCR_ATTR_KEY_ID] = { NLA_BINARY, 0 },
+ [NCR_ATTR_KEY_TYPE] = { NLA_U32, 0 },
+ [NCR_ATTR_IV] = { NLA_BINARY, 0 },
+ [NCR_ATTR_SECRET_KEY_BITS] = { NLA_U32, 0 },
+ [NCR_ATTR_RSA_MODULUS_BITS] = { NLA_U32, 0 },
+ [NCR_ATTR_RSA_E] = { NLA_BINARY, 0 },
+ [NCR_ATTR_RSA_ENCODING_METHOD] = { NLA_U32, 0 },
+ [NCR_ATTR_RSA_OAEP_HASH_ALGORITHM] = { NLA_NUL_STRING, 0 },
+ [NCR_ATTR_RSA_PSS_SALT_LENGTH] = { NLA_U32, 0 },
+ [NCR_ATTR_DSA_P_BITS] = { NLA_U32, 0 },
+ [NCR_ATTR_DSA_Q_BITS] = { NLA_U32, 0 },
+ [NCR_ATTR_DH_PRIME] = { NLA_BINARY, 0 },
+ [NCR_ATTR_DH_BASE] = { NLA_BINARY, 0 },
+ [NCR_ATTR_DH_PUBLIC] = { NLA_BINARY, 0 },
+ [NCR_ATTR_WANTED_ATTRS] = { NLA_BINARY, 0 },
+ [NCR_ATTR_SESSION_CLONE_FROM] = { NLA_U32, 0 },
+};
+
+void *__ncr_get_input_args(void *fixed, struct nlattr *tb[], size_t fixed_size,
+ u32 *input_size_ptr, const void __user *arg)
+{
+ size_t input_size, buf_size;
+ void *buf;
+ int ret;
+
+ if (unlikely(copy_from_user(fixed, arg, fixed_size))) {
+ err();
+ return ERR_PTR(-EFAULT);
+ }
+ input_size = *input_size_ptr;
+
+ /* NCR_GET_INPUT_ARGS/NCR_GET_INPUT_ARGS_NO_OUTPUT has verified
+ fixed_size is correctly aligned for a struct nlattr. */
+ if (input_size == 0)
+ input_size = fixed_size;
+ else if (unlikely(input_size < fixed_size)) {
+ err();
+ return ERR_PTR(-EINVAL);
+ }
+ buf_size = input_size - fixed_size;
+ if (unlikely(buf_size > NCR_MAX_ATTR_SIZE)) {
+ err();
+ return ERR_PTR(-EOVERFLOW);
+ }
+
+ if (buf_size == 0)
+ buf = NULL;
+ else {
+ const char __user *var_arg;
+
+ buf = kmalloc(buf_size, GFP_KERNEL);
+ if (unlikely(buf == NULL)) {
+ err();
+ return ERR_PTR(-ENOMEM);
+ }
+ var_arg = (const char __user *)arg + fixed_size;
+ if (unlikely(copy_from_user(buf, var_arg, buf_size))) {
+ err();
+ ret = -EFAULT;
+ goto err_buf;
+ }
+ }
+
+ ret = nla_parse(tb, NCR_ATTR_MAX, buf, buf_size, ncr_attr_policy);
+ if (ret != 0) {
+ err();
+ goto err_buf;
+ }
+
+ return buf;
+
+err_buf:
+ kfree(buf);
+ return ERR_PTR(ret);
+}
+
+static int update_output_size(void __user *arg, size_t output_size_offset,
+ u32 old_value, u32 new_value)
+{
+ if (old_value != 0 && old_value != new_value) {
+ u32 __user *dest;
+
+ dest = (u32 __user *)((char __user *)arg + output_size_offset);
+ return put_user(new_value, dest);
+ }
+ return 0;
+}
+
+void *__ncr_get_input_args_no_output(void *fixed, struct nlattr *tb[],
+ size_t fixed_size, u32 *input_size_ptr,
+ size_t output_size_offset,
+ void __user *arg)
+{
+ void *attr_buf;
+ u32 output_size;
+ int ret;
+
+ attr_buf = __ncr_get_input_args(fixed, tb, fixed_size, input_size_ptr,
+ arg);
+ if (IS_ERR(attr_buf))
+ return attr_buf;
+
+ output_size = *(const u32 *)((const char *)fixed + output_size_offset);
+ ret = update_output_size(arg, output_size_offset, output_size,
+ fixed_size);
+ if (ret != 0) {
+ kfree(attr_buf);
+ return ERR_PTR(ret);
+ }
+ return attr_buf;
+}
+
+int __ncr_out_init(struct ncr_out *out, const void *fixed, size_t fixed_size,
+ size_t output_size_offset, void __user *arg)
+{
+ u32 output_size;
+
+ /* NCR_OUT_INIT has verified fixed_size is correctly aligned for a
+ struct nlattr. */
+ output_size = *(const u32 *)((const char *)fixed + output_size_offset);
+ if (output_size == 0)
+ out->left = 0;
+ else {
+ /* NCR_OUT_INIT has verified fixed_size is correctly aligned for
+ a struct nlattr. */
+ if (output_size < fixed_size)
+ return -EINVAL;
+ out->left = min_t(size_t, output_size - fixed_size,
+ NCR_MAX_ATTR_SIZE);
+ }
+ out->buf = kmalloc(out->left, GFP_KERNEL);
+ if (out->buf == NULL)
+ return -ENOMEM;
+ out->p = out->buf;
+ out->arg = arg;
+ out->output_size_offset = output_size_offset;
+ out->fixed_size = fixed_size;
+ out->orig_output_size = output_size;
+ return 0;
+}
+
+int ncr_out_finish(struct ncr_out *out)
+{
+ size_t buf_size;
+
+ buf_size = (char *)out->p - (char *)out->buf;
+ if (buf_size != 0) {
+ if (unlikely(copy_to_user((char __user *)out->arg
+ + out->fixed_size,
+ out->buf, buf_size)))
+ return -EFAULT;
+ }
+
+ return update_output_size(out->arg, out->output_size_offset,
+ out->orig_output_size,
+ out->fixed_size + buf_size);
+}
+
+void ncr_out_free(struct ncr_out *out)
+{
+ kfree(out->buf);
+}
+
+struct nlattr *ncr_out_reserve(struct ncr_out *out, int attrtype, int attrlen)
+{
+ size_t needed;
+ struct nlattr *nla;
+
+ needed = nla_total_size(attrlen);
+ if (out->left < needed)
+ ERR_PTR(-ERANGE);
+ nla = out->p;
+ out->p = (char *)out->p + needed;
+ out->left -= needed;
+
+ nla->nla_len = nla_attr_size(attrlen);
+ nla->nla_type = attrtype;
+ memset((unsigned char *)nla + nla->nla_len, 0, nla_padlen(attrlen));
+ return nla;
+}
+
+int ncr_out_put(struct ncr_out *out, int attrtype, int attrlen, const void *data)
+{
+ struct nlattr *nla;
+
+ nla = ncr_out_reserve(out, attrtype, attrlen);
+ if (IS_ERR(nla))
+ return PTR_ERR(nla);
+ memcpy(nla_data(nla), data, attrlen);
+ return 0;
+}
+
+/**
+ * Initialize a nlattr with @attrtype as a buffer of maximum possible size in
+ * @out. The buffer must be finalized using ncr_out_commit_buffer.
+ */
+struct nlattr *ncr_out_begin_buffer(struct ncr_out *out, int attrtype)
+{
+ struct nlattr *nla;
+
+ if (out->left < NLA_HDRLEN)
+ return ERR_PTR(-ERANGE);
+ nla = out->p;
+
+ /* Ensure the rounding down of out->left does not decrease it below
+ NLA_HDRLEN. */
+ BUILD_BUG_ON(NLA_ALIGN(NLA_HDRLEN) != NLA_HDRLEN);
+ nla->nla_len = out->left & ~(NLA_ALIGNTO - 1);
+ nla->nla_type = attrtype;
+ return nla;
+}
+
+/**
+ * Set the length of buffer initialied in @out with ncr_out_begin_buffer() to
+ * @attrlen and allow adding more attributes.
+ */
+void ncr_out_commit_buffer(struct ncr_out *out, int attrlen)
+{
+ struct nlattr *nla;
+ size_t total;
+
+ nla = out->p;
+ nla->nla_len = nla_attr_size(attrlen);
+ memset((unsigned char *)nla + nla->nla_len, 0, nla_padlen(attrlen));
+ total = nla_total_size(attrlen);
+
+ out->p = (char *)out->p + total;
+ out->left -= total;
+}