Commit d0796d1e authored by Richard Alpe's avatar Richard Alpe Committed by David S. Miller
Browse files

tipc: convert legacy nl bearer dump to nl compat



Introduce a framework for dumping netlink data from the new netlink
API and formatting it to the old legacy API format. This is done by
looping the dump data and calling a format handler for each entity, in
this case a bearer.

We dump until either all data is dumped or we reach the limited buffer
size of the legacy API. Remember, the legacy API doesn't scale.

In this commit we convert TIPC_CMD_GET_BEARER_NAMES to use the compat
layer.
Signed-off-by: default avatarRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: default avatarErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
Reviewed-by: default avatarJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bfb3e5dd
......@@ -272,6 +272,11 @@ static inline int TLV_CHECK(const void *tlv, __u16 space, __u16 exp_type)
(ntohs(((struct tlv_desc *)tlv)->tlv_type) == exp_type);
}
static inline int TLV_GET_LEN(struct tlv_desc *tlv)
{
return ntohs(tlv->tlv_len);
}
static inline int TLV_SET(void *tlv, __u16 type, void *data, __u16 len)
{
struct tlv_desc *tlv_ptr;
......
......@@ -205,35 +205,6 @@ struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
return NULL;
}
/**
* tipc_bearer_get_names - record names of bearers in buffer
*/
struct sk_buff *tipc_bearer_get_names(struct net *net)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
struct sk_buff *buf;
struct tipc_bearer *b;
int i, j;
buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
if (!buf)
return NULL;
for (i = 0; media_info_array[i] != NULL; i++) {
for (j = 0; j < MAX_BEARERS; j++) {
b = rtnl_dereference(tn->bearer_list[j]);
if (!b)
continue;
if (b->media == media_info_array[i]) {
tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
b->name,
strlen(b->name) + 1);
}
}
}
return buf;
}
void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
......
......@@ -205,7 +205,6 @@ void tipc_disable_l2_media(struct tipc_bearer *b);
int tipc_l2_send_msg(struct net *net, struct sk_buff *buf,
struct tipc_bearer *b, struct tipc_media_addr *dest);
struct sk_buff *tipc_bearer_get_names(struct net *net);
void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest);
void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest);
struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name);
......
......@@ -252,9 +252,6 @@ struct sk_buff *tipc_cfg_do_cmd(struct net *net, u32 orig_node, u16 cmd,
rep_tlv_buf = tipc_nametbl_get(net, req_tlv_area,
req_tlv_space);
break;
case TIPC_CMD_GET_BEARER_NAMES:
rep_tlv_buf = tipc_bearer_get_names(net);
break;
case TIPC_CMD_GET_MEDIA_NAMES:
rep_tlv_buf = tipc_media_get_names();
break;
......
......@@ -33,9 +33,265 @@
#include "core.h"
#include "config.h"
#include "bearer.h"
#include <net/genetlink.h>
#include <linux/tipc_config.h>
/* The legacy API had an artificial message length limit called
* ULTRA_STRING_MAX_LEN.
*/
#define ULTRA_STRING_MAX_LEN 32768
#define TIPC_SKB_MAX TLV_SPACE(ULTRA_STRING_MAX_LEN)
#define REPLY_TRUNCATED "<truncated>\n"
struct tipc_nl_compat_msg {
u16 cmd;
int rep_size;
struct sk_buff *rep;
struct tlv_desc *req;
struct sock *dst_sk;
};
struct tipc_nl_compat_cmd_dump {
int (*dumpit)(struct sk_buff *, struct netlink_callback *);
int (*format)(struct tipc_nl_compat_msg *msg, struct nlattr **attrs);
};
static int tipc_skb_tailroom(struct sk_buff *skb)
{
int tailroom;
int limit;
tailroom = skb_tailroom(skb);
limit = TIPC_SKB_MAX - skb->len;
if (tailroom < limit)
return tailroom;
return limit;
}
static int tipc_add_tlv(struct sk_buff *skb, u16 type, void *data, u16 len)
{
struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(skb);
if (tipc_skb_tailroom(skb) < TLV_SPACE(len))
return -EMSGSIZE;
skb_put(skb, TLV_SPACE(len));
tlv->tlv_type = htons(type);
tlv->tlv_len = htons(TLV_LENGTH(len));
if (len && data)
memcpy(TLV_DATA(tlv), data, len);
return 0;
}
static struct sk_buff *tipc_tlv_alloc(int size)
{
int hdr_len;
struct sk_buff *buf;
size = TLV_SPACE(size);
hdr_len = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN);
buf = alloc_skb(hdr_len + size, GFP_KERNEL);
if (!buf)
return NULL;
skb_reserve(buf, hdr_len);
return buf;
}
static struct sk_buff *tipc_get_err_tlv(char *str)
{
int str_len = strlen(str) + 1;
struct sk_buff *buf;
buf = tipc_tlv_alloc(TLV_SPACE(str_len));
if (buf)
tipc_add_tlv(buf, TIPC_TLV_ERROR_STRING, str, str_len);
return buf;
}
static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd,
struct tipc_nl_compat_msg *msg,
struct sk_buff *arg)
{
int len = 0;
int err;
struct sk_buff *buf;
struct nlmsghdr *nlmsg;
struct netlink_callback cb;
memset(&cb, 0, sizeof(cb));
cb.nlh = (struct nlmsghdr *)arg->data;
cb.skb = arg;
buf = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
buf->sk = msg->dst_sk;
do {
int rem;
len = (*cmd->dumpit)(buf, &cb);
nlmsg_for_each_msg(nlmsg, nlmsg_hdr(buf), len, rem) {
struct nlattr **attrs;
err = tipc_nlmsg_parse(nlmsg, &attrs);
if (err)
goto err_out;
err = (*cmd->format)(msg, attrs);
if (err)
goto err_out;
if (tipc_skb_tailroom(msg->rep) <= 1) {
err = -EMSGSIZE;
goto err_out;
}
}
skb_reset_tail_pointer(buf);
buf->len = 0;
} while (len);
err = 0;
err_out:
kfree_skb(buf);
if (err == -EMSGSIZE) {
/* The legacy API only considered messages filling
* "ULTRA_STRING_MAX_LEN" to be truncated.
*/
if ((TIPC_SKB_MAX - msg->rep->len) <= 1) {
char *tail = skb_tail_pointer(msg->rep);
if (*tail != '\0')
sprintf(tail - sizeof(REPLY_TRUNCATED) - 1,
REPLY_TRUNCATED);
}
return 0;
}
return err;
}
static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd,
struct tipc_nl_compat_msg *msg)
{
int err;
struct sk_buff *arg;
msg->rep = tipc_tlv_alloc(msg->rep_size);
if (!msg->rep)
return -ENOMEM;
arg = nlmsg_new(0, GFP_KERNEL);
if (!arg) {
kfree_skb(msg->rep);
return -ENOMEM;
}
err = __tipc_nl_compat_dumpit(cmd, msg, arg);
if (err)
kfree_skb(msg->rep);
kfree_skb(arg);
return err;
}
static int tipc_nl_compat_bearer_dump(struct tipc_nl_compat_msg *msg,
struct nlattr **attrs)
{
struct nlattr *bearer[TIPC_NLA_BEARER_MAX + 1];
nla_parse_nested(bearer, TIPC_NLA_BEARER_MAX, attrs[TIPC_NLA_BEARER],
NULL);
return tipc_add_tlv(msg->rep, TIPC_TLV_BEARER_NAME,
nla_data(bearer[TIPC_NLA_BEARER_NAME]),
nla_len(bearer[TIPC_NLA_BEARER_NAME]));
}
static int tipc_nl_compat_handle(struct tipc_nl_compat_msg *msg)
{
struct tipc_nl_compat_cmd_dump dump;
memset(&dump, 0, sizeof(dump));
switch (msg->cmd) {
case TIPC_CMD_GET_BEARER_NAMES:
msg->rep_size = MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME);
dump.dumpit = tipc_nl_bearer_dump;
dump.format = tipc_nl_compat_bearer_dump;
return tipc_nl_compat_dumpit(&dump, msg);
}
return -EOPNOTSUPP;
}
static int tipc_nl_compat_recv(struct sk_buff *skb, struct genl_info *info)
{
int err;
int len;
struct tipc_nl_compat_msg msg;
struct nlmsghdr *req_nlh;
struct nlmsghdr *rep_nlh;
struct tipc_genlmsghdr *req_userhdr = info->userhdr;
struct net *net = genl_info_net(info);
memset(&msg, 0, sizeof(msg));
req_nlh = (struct nlmsghdr *)skb->data;
msg.req = nlmsg_data(req_nlh) + GENL_HDRLEN + TIPC_GENL_HDRLEN;
msg.cmd = req_userhdr->cmd;
msg.dst_sk = info->dst_sk;
if ((msg.cmd & 0xC000) && (!netlink_net_capable(skb, CAP_NET_ADMIN))) {
msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_NET_ADMIN);
err = -EACCES;
goto send;
}
len = nlmsg_attrlen(req_nlh, GENL_HDRLEN + TIPC_GENL_HDRLEN);
if (TLV_GET_LEN(msg.req) && !TLV_OK(msg.req, len)) {
msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED);
err = -EOPNOTSUPP;
goto send;
}
err = tipc_nl_compat_handle(&msg);
if (err == -EOPNOTSUPP)
msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED);
else if (err == -EINVAL)
msg.rep = tipc_get_err_tlv(TIPC_CFG_TLV_ERROR);
send:
if (!msg.rep)
return err;
len = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN);
skb_push(msg.rep, len);
rep_nlh = nlmsg_hdr(msg.rep);
memcpy(rep_nlh, info->nlhdr, len);
rep_nlh->nlmsg_len = msg.rep->len;
genlmsg_unicast(net, msg.rep, NETLINK_CB(skb).portid);
return err;
}
static int handle_cmd(struct sk_buff *skb, struct genl_info *info)
{
struct net *net = genl_info_net(info);
......@@ -69,6 +325,22 @@ static int handle_cmd(struct sk_buff *skb, struct genl_info *info)
return 0;
}
/* Temporary function to keep functionality throughout the patchset
* without having to mess with the global variables and other trickery
* of the old API.
*/
static int tipc_nl_compat_tmp_wrap(struct sk_buff *skb, struct genl_info *info)
{
struct tipc_genlmsghdr *req = info->userhdr;
switch (req->cmd) {
case TIPC_CMD_GET_BEARER_NAMES:
return tipc_nl_compat_recv(skb, info);
}
return handle_cmd(skb, info);
}
static struct genl_family tipc_genl_compat_family = {
.id = GENL_ID_GENERATE,
.name = TIPC_GENL_NAME,
......@@ -81,7 +353,7 @@ static struct genl_family tipc_genl_compat_family = {
static struct genl_ops tipc_genl_compat_ops[] = {
{
.cmd = TIPC_GENL_CMD,
.doit = handle_cmd,
.doit = tipc_nl_compat_tmp_wrap,
},
};
......
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