[XFRM]: User interface for handling XFRM_MSG_MIGRATE

Add user interface for handling XFRM_MSG_MIGRATE. The message is issued
by user application. When kernel receives the message, procedure of
updating XFRM databases will take place.

Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 173 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 82f36d396fca..079a5d315759 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1632,6 +1632,176 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
         return 0;
 }
 
+#ifdef CONFIG_XFRM_MIGRATE
+static int verify_user_migrate(struct rtattr **xfrma)
+{
+        struct rtattr *rt = xfrma[XFRMA_MIGRATE-1];
+        struct xfrm_user_migrate *um;
+
+        if (!rt)
+                return -EINVAL;
+
+        if ((rt->rta_len - sizeof(*rt)) < sizeof(*um))
+                return -EINVAL;
+
+        return 0;
+}
+
+static int copy_from_user_migrate(struct xfrm_migrate *ma,
+                                  struct rtattr **xfrma, int *num)
+{
+        struct rtattr *rt = xfrma[XFRMA_MIGRATE-1];
+        struct xfrm_user_migrate *um;
+        int i, num_migrate;
+
+        um = RTA_DATA(rt);
+        num_migrate = (rt->rta_len - sizeof(*rt)) / sizeof(*um);
+
+        if (num_migrate <= 0 || num_migrate > XFRM_MAX_DEPTH)
+                return -EINVAL;
+
+        for (i = 0; i < num_migrate; i++, um++, ma++) {
+                memcpy(&ma->old_daddr, &um->old_daddr, sizeof(ma->old_daddr));
+                memcpy(&ma->old_saddr, &um->old_saddr, sizeof(ma->old_saddr));
+                memcpy(&ma->new_daddr, &um->new_daddr, sizeof(ma->new_daddr));
+                memcpy(&ma->new_saddr, &um->new_saddr, sizeof(ma->new_saddr));
+
+                ma->proto = um->proto;
+                ma->mode = um->mode;
+                ma->reqid = um->reqid;
+
+                ma->old_family = um->old_family;
+                ma->new_family = um->new_family;
+        }
+
+        *num = i;
+        return 0;
+}
+
+static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
+                           struct rtattr **xfrma)
+{
+        struct xfrm_userpolicy_id *pi = NLMSG_DATA(nlh);
+        struct xfrm_migrate m[XFRM_MAX_DEPTH];
+        u8 type;
+        int err;
+        int n = 0;
+
+        err = verify_user_migrate((struct rtattr **)xfrma);
+        if (err)
+                return err;
+
+        err = copy_from_user_policy_type(&type, (struct rtattr **)xfrma);
+        if (err)
+                return err;
+
+        err = copy_from_user_migrate((struct xfrm_migrate *)m,
+                                     (struct rtattr **)xfrma, &n);
+        if (err)
+                return err;
+
+        if (!n)
+                return 0;
+
+        xfrm_migrate(&pi->sel, pi->dir, type, m, n);
+
+        return 0;
+}
+#else
+static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
+                           struct rtattr **xfrma)
+{
+        return -ENOPROTOOPT;
+}
+#endif
+
+#ifdef CONFIG_XFRM_MIGRATE
+static int copy_to_user_migrate(struct xfrm_migrate *m, struct sk_buff *skb)
+{
+        struct xfrm_user_migrate um;
+
+        memset(&um, 0, sizeof(um));
+        um.proto = m->proto;
+        um.mode = m->mode;
+        um.reqid = m->reqid;
+        um.old_family = m->old_family;
+        memcpy(&um.old_daddr, &m->old_daddr, sizeof(um.old_daddr));
+        memcpy(&um.old_saddr, &m->old_saddr, sizeof(um.old_saddr));
+        um.new_family = m->new_family;
+        memcpy(&um.new_daddr, &m->new_daddr, sizeof(um.new_daddr));
+        memcpy(&um.new_saddr, &m->new_saddr, sizeof(um.new_saddr));
+
+        RTA_PUT(skb, XFRMA_MIGRATE, sizeof(um), &um);
+        return 0;
+
+rtattr_failure:
+        return -1;
+}
+
+static int build_migrate(struct sk_buff *skb, struct xfrm_migrate *m,
+                         int num_migrate, struct xfrm_selector *sel,
+                         u8 dir, u8 type)
+{
+        struct xfrm_migrate *mp;
+        struct xfrm_userpolicy_id *pol_id;
+        struct nlmsghdr *nlh;
+        unsigned char *b = skb->tail;
+        int i;
+
+        nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_MIGRATE, sizeof(*pol_id));
+        pol_id = NLMSG_DATA(nlh);
+        nlh->nlmsg_flags = 0;
+
+        /* copy data from selector, dir, and type to the pol_id */
+        memset(pol_id, 0, sizeof(*pol_id));
+        memcpy(&pol_id->sel, sel, sizeof(pol_id->sel));
+        pol_id->dir = dir;
+
+        if (copy_to_user_policy_type(type, skb) < 0)
+                goto nlmsg_failure;
+
+        for (i = 0, mp = m ; i < num_migrate; i++, mp++) {
+                if (copy_to_user_migrate(mp, skb) < 0)
+                        goto nlmsg_failure;
+        }
+
+        nlh->nlmsg_len = skb->tail - b;
+        return skb->len;
+nlmsg_failure:
+        skb_trim(skb, b - skb->data);
+        return -1;
+}
+
+static int xfrm_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
+                             struct xfrm_migrate *m, int num_migrate)
+{
+        struct sk_buff *skb;
+        size_t len;
+
+        len = RTA_SPACE(sizeof(struct xfrm_user_migrate) * num_migrate);
+        len += NLMSG_SPACE(sizeof(struct xfrm_userpolicy_id));
+#ifdef CONFIG_XFRM_SUB_POLICY
+        len += RTA_SPACE(sizeof(struct xfrm_userpolicy_type));
+#endif
+        skb = alloc_skb(len, GFP_ATOMIC);
+        if (skb == NULL)
+                return -ENOMEM;
+
+        /* build migrate */
+        if (build_migrate(skb, m, num_migrate, sel, dir, type) < 0)
+                BUG();
+
+        NETLINK_CB(skb).dst_group = XFRMNLGRP_MIGRATE;
+        return netlink_broadcast(xfrm_nl, skb, 0, XFRMNLGRP_MIGRATE,
+                                 GFP_ATOMIC);
+}
+#else
+static int xfrm_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
+                             struct xfrm_migrate *m, int num_migrate)
+{
+        return -ENOPROTOOPT;
+}
+#endif
 
 #define XMSGSIZE(type) NLMSG_LENGTH(sizeof(struct type))
 
@@ -1653,6 +1823,7 @@ static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
         [XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
         [XFRM_MSG_GETAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
         [XFRM_MSG_REPORT      - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_report),
+        [XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
 };
 
 #undef XMSGSIZE
@@ -1679,6 +1850,7 @@ static struct xfrm_link {
         [XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = { .doit = xfrm_flush_policy  },
         [XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = { .doit = xfrm_new_ae  },
         [XFRM_MSG_GETAE       - XFRM_MSG_BASE] = { .doit = xfrm_get_ae  },
+        [XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = { .doit = xfrm_do_migrate    },
 };
 
 static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
@@ -2285,6 +2457,7 @@ static struct xfrm_mgr netlink_mgr = {
         .compile_policy = xfrm_compile_policy,
         .notify_policy  = xfrm_send_policy_notify,
         .report         = xfrm_send_report,
+        .migrate        = xfrm_send_migrate,
 };
 
 static int __init xfrm_user_init(void)