[PATCHv2 2/7] Move net/ceph/armor to lib/ and add docs
From: Dan Aloni
Date: Sat Jan 13 2018 - 16:38:01 EST
Plus, add functions that assist in managing buffer bounds.
Signed-off-by: Dan Aloni <dan@xxxxxxxxxxxx>
---
include/linux/base64-armor.h | 65 ++++++++++++++++++++++++++++++++++
lib/Kconfig | 7 ++++
lib/Makefile | 1 +
net/ceph/armor.c => lib/base64-armor.c | 13 ++++---
net/ceph/Kconfig | 1 +
net/ceph/Makefile | 2 +-
net/ceph/crypto.c | 3 +-
net/ceph/crypto.h | 4 ---
8 files changed, 85 insertions(+), 11 deletions(-)
create mode 100644 include/linux/base64-armor.h
rename net/ceph/armor.c => lib/base64-armor.c (86%)
diff --git a/include/linux/base64-armor.h b/include/linux/base64-armor.h
new file mode 100644
index 000000000000..e5160c77bb2f
--- /dev/null
+++ b/include/linux/base64-armor.h
@@ -0,0 +1,65 @@
+#ifndef __LINUX_BASE64_ARMOR_H__
+#define __LINUX_BASE64_ARMOR_H__
+
+#include <linux/types.h>
+
+/**
+ * base64_armor: Perform armored base64 encoding. Output may or may
+ * not contain newlines, depending on input length.
+ *
+ * @dst: Beginning of the destination buffer.
+ * @src: Beginning of the source buffer.
+ * @end: Sentinel for the source buffer, pointing one byte after the
+ * last byte to be encoded.
+ *
+ * Returns the number of bytes written to the destination buffer.
+ *
+ * _Neither_ the input or output are expected to be NULL-terminated.
+ *
+ * The number of output bytes is exactly (n * 4 + (n / 16)) where
+ * n = ((end - src) + 2) / 3. A less stringent but more wasteful
+ * validation for output buffer size can be: 4 + (end - src) * 2.
+ *
+ * See base64_encode_buffer_bound below.
+ */
+
+extern int base64_armor(char *dst, const char *src, const char *end);
+
+/**
+ * base64_unarmor: Perform armored base64 decoding.
+ *
+ * @dst: Beginning of the destination buffer.
+ * @src: Beginning of the source buffer
+ * @end: Sentinel for the source buffer, pointing one byte after the
+ * last byte to be encoded.
+ *
+ * Returns the number of bytes written to the destination buffer, or
+ * -EINVAL if the source buffer contains invalid bytes.
+ *
+ * _Neither_ the input or output are expected to be NULL-terminated.
+ *
+ * It can be assumed that the number of output bytes is less or
+ * equals to: 3 * ((end - src) / 4).
+ *
+ * See base64_decode_buffer_bound below.
+ */
+extern int base64_unarmor(char *dst, const char *src, const char *end);
+
+
+/*
+ * Utility functions for buffer upper bounds:
+ */
+
+static inline size_t base64_encode_buffer_bound(size_t src_len)
+{
+ size_t n = (src_len + 2) / 3;
+
+ return (n * 4 + (n / 16));
+}
+
+static inline size_t base64_decode_buffer_bound(size_t src_len)
+{
+ return 3 * (src_len / 4);
+}
+
+#endif
diff --git a/lib/Kconfig b/lib/Kconfig
index c5e84fbcb30b..caddcaebbc2f 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -188,6 +188,13 @@ config CRC8
when they need to do cyclic redundancy check according CRC8
algorithm. Module will be called crc8.
+config BASE64_ARMOR
+ tristate "BASE64 encoding/decoding functions"
+ help
+ This option provides BASE64 encoding and decoding functions.
+ Module name will be base64-armor if this code is built as a
+ module.
+
config XXHASH
tristate
diff --git a/lib/Makefile b/lib/Makefile
index d11c48ec8ffd..47335d28f77f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -94,6 +94,7 @@ ifneq ($(CONFIG_HAVE_DEC_LOCK),y)
lib-y += dec_and_lock.o
endif
+obj-$(CONFIG_BASE64_ARMOR) += base64-armor.o
obj-$(CONFIG_BITREVERSE) += bitrev.o
obj-$(CONFIG_RATIONAL) += rational.o
obj-$(CONFIG_CRC_CCITT) += crc-ccitt.o
diff --git a/net/ceph/armor.c b/lib/base64-armor.c
similarity index 86%
rename from net/ceph/armor.c
rename to lib/base64-armor.c
index 0db8065928df..e07d25ac2850 100644
--- a/net/ceph/armor.c
+++ b/lib/base64-armor.c
@@ -1,9 +1,8 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/errno.h>
-
-int ceph_armor(char *dst, const char *src, const char *end);
-int ceph_unarmor(char *dst, const char *src, const char *end);
+#include <linux/module.h>
+#include <linux/base64-armor.h>
/*
* base64 encode/decode.
@@ -34,7 +33,7 @@ static int decode_bits(char c)
return -EINVAL;
}
-int ceph_armor(char *dst, const char *src, const char *end)
+int base64_armor(char *dst, const char *src, const char *end)
{
int olen = 0;
int line = 0;
@@ -71,8 +70,9 @@ int ceph_armor(char *dst, const char *src, const char *end)
}
return olen;
}
+EXPORT_SYMBOL(base64_unarmor);
-int ceph_unarmor(char *dst, const char *src, const char *end)
+int base64_unarmor(char *dst, const char *src, const char *end)
{
int olen = 0;
@@ -104,3 +104,6 @@ int ceph_unarmor(char *dst, const char *src, const char *end)
}
return olen;
}
+EXPORT_SYMBOL(base64_armor);
+
+MODULE_LICENSE("GPL v2");
diff --git a/net/ceph/Kconfig b/net/ceph/Kconfig
index f8cceb99e732..5c4e7d0f2896 100644
--- a/net/ceph/Kconfig
+++ b/net/ceph/Kconfig
@@ -2,6 +2,7 @@ config CEPH_LIB
tristate "Ceph core library"
depends on INET
select LIBCRC32C
+ select BASE64_ARMOR
select CRYPTO_AES
select CRYPTO_CBC
select CRYPTO
diff --git a/net/ceph/Makefile b/net/ceph/Makefile
index b4bded4b5396..bf6f5e34bdb1 100644
--- a/net/ceph/Makefile
+++ b/net/ceph/Makefile
@@ -10,7 +10,7 @@ libceph-y := ceph_common.o messenger.o msgpool.o buffer.o pagelist.o \
osd_client.o osdmap.o crush/crush.o crush/mapper.o crush/hash.o \
debugfs.o \
auth.o auth_none.o \
- crypto.o armor.o \
+ crypto.o \
auth_x.o \
ceph_fs.o ceph_strings.o ceph_hash.o \
pagevec.o snapshot.o string_table.o
diff --git a/net/ceph/crypto.c b/net/ceph/crypto.c
index bf9d079cbafd..25e04e3b1aa4 100644
--- a/net/ceph/crypto.c
+++ b/net/ceph/crypto.c
@@ -10,6 +10,7 @@
#include <crypto/skcipher.h>
#include <linux/key-type.h>
#include <linux/sched/mm.h>
+#include <linux/base64-armor.h>
#include <keys/ceph-type.h>
#include <keys/user-type.h>
@@ -115,7 +116,7 @@ int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *inkey)
buf = kmalloc(blen, GFP_NOFS);
if (!buf)
return -ENOMEM;
- blen = ceph_unarmor(buf, inkey, inkey+inlen);
+ blen = base64_unarmor(buf, inkey, inkey+inlen);
if (blen < 0) {
kfree(buf);
return blen;
diff --git a/net/ceph/crypto.h b/net/ceph/crypto.h
index bb45c7d43739..a0236cbad530 100644
--- a/net/ceph/crypto.h
+++ b/net/ceph/crypto.h
@@ -29,8 +29,4 @@ int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
int ceph_crypto_init(void);
void ceph_crypto_shutdown(void);
-/* armor.c */
-int ceph_armor(char *dst, const char *src, const char *end);
-int ceph_unarmor(char *dst, const char *src, const char *end);
-
#endif
--
2.14.3