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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /crypto/dh_helper.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'crypto/dh_helper.c')
-rw-r--r--crypto/dh_helper.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/crypto/dh_helper.c b/crypto/dh_helper.c
new file mode 100644
index 000000000..2d4998793
--- /dev/null
+++ b/crypto/dh_helper.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <crypto/dh.h>
+#include <crypto/kpp.h>
+
+#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 3 * sizeof(int))
+
+static inline u8 *dh_pack_data(u8 *dst, u8 *end, const void *src, size_t size)
+{
+ if (!dst || size > end - dst)
+ return NULL;
+ memcpy(dst, src, size);
+ return dst + size;
+}
+
+static inline const u8 *dh_unpack_data(void *dst, const void *src, size_t size)
+{
+ memcpy(dst, src, size);
+ return src + size;
+}
+
+static inline unsigned int dh_data_size(const struct dh *p)
+{
+ return p->key_size + p->p_size + p->g_size;
+}
+
+unsigned int crypto_dh_key_len(const struct dh *p)
+{
+ return DH_KPP_SECRET_MIN_SIZE + dh_data_size(p);
+}
+EXPORT_SYMBOL_GPL(crypto_dh_key_len);
+
+int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params)
+{
+ u8 *ptr = buf;
+ u8 * const end = ptr + len;
+ struct kpp_secret secret = {
+ .type = CRYPTO_KPP_SECRET_TYPE_DH,
+ .len = len
+ };
+
+ if (unlikely(!len))
+ return -EINVAL;
+
+ ptr = dh_pack_data(ptr, end, &secret, sizeof(secret));
+ ptr = dh_pack_data(ptr, end, &params->key_size,
+ sizeof(params->key_size));
+ ptr = dh_pack_data(ptr, end, &params->p_size, sizeof(params->p_size));
+ ptr = dh_pack_data(ptr, end, &params->g_size, sizeof(params->g_size));
+ ptr = dh_pack_data(ptr, end, params->key, params->key_size);
+ ptr = dh_pack_data(ptr, end, params->p, params->p_size);
+ ptr = dh_pack_data(ptr, end, params->g, params->g_size);
+ if (ptr != end)
+ return -EINVAL;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_dh_encode_key);
+
+int __crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params)
+{
+ const u8 *ptr = buf;
+ struct kpp_secret secret;
+
+ if (unlikely(!buf || len < DH_KPP_SECRET_MIN_SIZE))
+ return -EINVAL;
+
+ ptr = dh_unpack_data(&secret, ptr, sizeof(secret));
+ if (secret.type != CRYPTO_KPP_SECRET_TYPE_DH)
+ return -EINVAL;
+
+ ptr = dh_unpack_data(&params->key_size, ptr, sizeof(params->key_size));
+ ptr = dh_unpack_data(&params->p_size, ptr, sizeof(params->p_size));
+ ptr = dh_unpack_data(&params->g_size, ptr, sizeof(params->g_size));
+ if (secret.len != crypto_dh_key_len(params))
+ return -EINVAL;
+
+ /* Don't allocate memory. Set pointers to data within
+ * the given buffer
+ */
+ params->key = (void *)ptr;
+ params->p = (void *)(ptr + params->key_size);
+ params->g = (void *)(ptr + params->key_size + params->p_size);
+
+ return 0;
+}
+
+int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params)
+{
+ int err;
+
+ err = __crypto_dh_decode_key(buf, len, params);
+ if (err)
+ return err;
+
+ /*
+ * Don't permit the buffer for 'key' or 'g' to be larger than 'p', since
+ * some drivers assume otherwise.
+ */
+ if (params->key_size > params->p_size ||
+ params->g_size > params->p_size)
+ return -EINVAL;
+
+ /*
+ * Don't permit 'p' to be 0. It's not a prime number, and it's subject
+ * to corner cases such as 'mod 0' being undefined or
+ * crypto_kpp_maxsize() returning 0.
+ */
+ if (memchr_inv(params->p, 0, params->p_size) == NULL)
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_dh_decode_key);