[RFC,2/9] libceph: add ceph_decode_entity_addr

Commit Message

Jeff Layton June 5, 2019, 1:10 p.m. UTC

Add a way to decode an entity_addr_t. Once CEPH_FEATURE_MSG_ADDR2 is
enabled, the server daemons will start encoding entity_addr_t
differently.

Add a new helper function that can handle either format.

Signed-off-by: Jeff Layton <[e-mail]>
---
 include/linux/ceph/decode.h |  2 +
 net/ceph/Makefile           |  2 +-
 net/ceph/decode.c           | 75 +++++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 1 deletion(-)
 create mode 100644 net/ceph/decode.c

Patch

diff --git a/include/linux/ceph/decode.h b/include/linux/ceph/decode.h
index a6c2a48d42e0..1c0a665bfc03 100644
--- a/include/linux/ceph/decode.h
+++ b/include/linux/ceph/decode.h
@@ -230,6 +230,8 @@  static inline void ceph_decode_addr(struct ceph_entity_addr *a)
 	WARN_ON(a->in_addr.ss_family == 512);
 }
 
+extern int ceph_decode_entity_addr(void **p, void *end,
+				   struct ceph_entity_addr *addr);
 /*
  * encoders
  */
diff --git a/net/ceph/Makefile b/net/ceph/Makefile
index db09defe27d0..59d0ba2072de 100644
--- a/net/ceph/Makefile
+++ b/net/ceph/Makefile
@@ -5,7 +5,7 @@ 
 obj-$(CONFIG_CEPH_LIB) += libceph.o
 
 libceph-y := ceph_common.o messenger.o msgpool.o buffer.o pagelist.o \
-	mon_client.o \
+	mon_client.o decode.o \
 	cls_lock_client.o \
 	osd_client.o osdmap.o crush/crush.o crush/mapper.o crush/hash.o \
 	striper.o \
diff --git a/net/ceph/decode.c b/net/ceph/decode.c
new file mode 100644
index 000000000000..27edf5d341ec
--- /dev/null
+++ b/net/ceph/decode.c
@@ -0,0 +1,75 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/ceph/decode.h>
+
+int
+ceph_decode_entity_addr(void **p, void *end, struct ceph_entity_addr *addr)
+{
+	u8 marker, v, compat;
+	u32 len;
+
+	ceph_decode_8_safe(p, end, marker, bad);
+	if (marker == 1) {
+		ceph_decode_8_safe(p, end, v, bad);
+		ceph_decode_8_safe(p, end, compat, bad);
+		if (!v || compat != 1)
+			goto bad;
+		/* FIXME: sanity check? */
+		ceph_decode_32_safe(p, end, len, bad);
+		/* type is __le32, so we must copy into place as-is */
+		ceph_decode_copy_safe(p, end, &addr->type,
+					sizeof(addr->type), bad);
+
+		/*
+		 * TYPE_NONE == 0
+		 * TYPE_LEGACY == 1
+		 *
+		 * Clients that don't support ADDR2 always send TYPE_NONE.
+		 * For now, since all we support is msgr1, just set this to 0
+		 * when we get a TYPE_LEGACY type.
+		 */
+		if (addr->type == cpu_to_le32(1))
+			addr->type = 0;
+	} else if (marker == 0) {
+		addr->type = 0;
+		/* Skip rest of type field */
+		ceph_decode_skip_n(p, end, 3, bad);
+	} else {
+		goto bad;
+	}
+
+	ceph_decode_need(p, end, sizeof(addr->nonce), bad);
+	ceph_decode_copy(p, &addr->nonce, sizeof(addr->nonce));
+
+	/* addr length */
+	if (marker ==  1) {
+		ceph_decode_32_safe(p, end, len, bad);
+		if (len > sizeof(addr->in_addr))
+			goto bad;
+	} else  {
+		len = sizeof(addr->in_addr);
+	}
+
+	memset(&addr->in_addr, 0, sizeof(addr->in_addr));
+
+	if (len) {
+		ceph_decode_need(p, end, len, bad);
+		ceph_decode_copy(p, &addr->in_addr, len);
+
+		/*
+		 * Fix up sa_family. Legacy encoding sends it in BE, addr2
+		 * encoding uses LE.
+		 */
+		if (marker == 1)
+			addr->in_addr.ss_family =
+				le16_to_cpu((__force __le16)addr->in_addr.ss_family);
+		else
+			addr->in_addr.ss_family =
+				be16_to_cpu((__force __be16)addr->in_addr.ss_family);
+	}
+	return 0;
+bad:
+	return -EINVAL;
+}
+EXPORT_SYMBOL(ceph_decode_entity_addr);
+