diff options
Diffstat (limited to 'net/tipc/msg.c')
| -rw-r--r-- | net/tipc/msg.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/net/tipc/msg.c b/net/tipc/msg.c index 4093b4c94d26..6070dd0ec634 100644 --- a/net/tipc/msg.c +++ b/net/tipc/msg.c @@ -37,6 +37,8 @@ #include "core.h" #include "msg.h" +#define MAX_FORWARD_SIZE 1024 + static unsigned int align(unsigned int i) { return (i + 3) & ~3u; @@ -328,3 +330,43 @@ bool tipc_msg_make_bundle(struct sk_buff **buf, u32 mtu, u32 dnode) *buf = bbuf; return true; } + +/** + * tipc_msg_reverse(): swap source and destination addresses and add error code + * @buf: buffer containing message to be reversed + * @dnode: return value: node where to send message after reversal + * @err: error code to be set in message + * Consumes buffer if failure + * Returns true if success, otherwise false + */ +bool tipc_msg_reverse(struct sk_buff *buf, u32 *dnode, int err) +{ + struct tipc_msg *msg = buf_msg(buf); + uint imp = msg_importance(msg); + struct tipc_msg ohdr; + uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE); + + if (skb_linearize(buf) || !msg_isdata(msg)) + goto exit; + if (msg_dest_droppable(msg) || msg_errcode(msg)) + goto exit; + + memcpy(&ohdr, msg, msg_hdr_sz(msg)); + msg_set_importance(msg, min_t(uint, ++imp, TIPC_CRITICAL_IMPORTANCE)); + msg_set_errcode(msg, err); + msg_set_origport(msg, msg_destport(&ohdr)); + msg_set_destport(msg, msg_origport(&ohdr)); + msg_set_prevnode(msg, tipc_own_addr); + if (!msg_short(msg)) { + msg_set_orignode(msg, msg_destnode(&ohdr)); + msg_set_destnode(msg, msg_orignode(&ohdr)); + } + msg_set_size(msg, msg_hdr_sz(msg) + rdsz); + skb_trim(buf, msg_size(msg)); + skb_orphan(buf); + *dnode = msg_orignode(&ohdr); + return true; +exit: + kfree_skb(buf); + return false; +} |