xfrm: MIGRATE enhancements (draft-ebalard-mext-pfkey-enhanced-migrate)

Provides implementation of the enhancements of XFRM/PF_KEY MIGRATE mechanism
specified in draft-ebalard-mext-pfkey-enhanced-migrate-00. Defines associated
PF_KEY SADB_X_EXT_KMADDRESS extension and XFRM/netlink XFRMA_KMADDRESS
attribute.

Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/pfkeyv2.h b/include/linux/pfkeyv2.h
index 700725d..01b2629 100644 (file)
--- a/include/linux/pfkeyv2.h
+++ b/include/linux/pfkeyv2.h
@@ -226,6 +226,15 @@ struct sadb_x_sec_ctx {
 } __attribute__((packed));
 /* sizeof(struct sadb_sec_ctx) = 8 */
 
+/* Used by MIGRATE to pass addresses IKE will use to perform
+ * negotiation with the peer */
+struct sadb_x_kmaddress {
+       uint16_t        sadb_x_kmaddress_len;
+       uint16_t        sadb_x_kmaddress_exttype;
+       uint32_t        sadb_x_kmaddress_reserved;
+} __attribute__((packed));
+/* sizeof(struct sadb_x_kmaddress) == 8 */
+
 /* Message types */
 #define SADB_RESERVED          0
 #define SADB_GETSPI            1
@@ -346,7 +355,9 @@ struct sadb_x_sec_ctx {
 #define SADB_X_EXT_NAT_T_DPORT         22
 #define SADB_X_EXT_NAT_T_OA            23
 #define SADB_X_EXT_SEC_CTX             24
-#define SADB_EXT_MAX                   24
+/* Used with MIGRATE to pass @ to IKE for negotiation */
+#define SADB_X_EXT_KMADDRESS           25
+#define SADB_EXT_MAX                   25
 
 /* Identity Extension values */
 #define SADB_IDENTTYPE_RESERVED        0

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index fb0c215..4bc1e6b 100644 (file)
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -279,6 +279,7 @@ enum xfrm_attr_type_t {
        XFRMA_POLICY_TYPE,      /* struct xfrm_userpolicy_type */
        XFRMA_MIGRATE,
        XFRMA_ALG_AEAD,         /* struct xfrm_algo_aead */
+       XFRMA_KMADDRESS,        /* struct xfrm_user_kmaddress */
        __XFRMA_MAX
 
 #define XFRMA_MAX (__XFRMA_MAX - 1)
@@ -415,6 +416,15 @@ struct xfrm_user_report {
        struct xfrm_selector            sel;
 };
 
+/* Used by MIGRATE to pass addresses IKE should use to perform
+ * SA negotiation with the peer */
+struct xfrm_user_kmaddress {
+       xfrm_address_t                  local;
+       xfrm_address_t                  remote;
+       __u32                           reserved;
+       __u16                           family;
+};
+
 struct xfrm_user_migrate {
        xfrm_address_t                  old_daddr;
        xfrm_address_t                  old_saddr;

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index b98d205..11c890a 100644 (file)
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -492,6 +492,13 @@ struct xfrm_policy
        struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 };
 
+struct xfrm_kmaddress {
+       xfrm_address_t          local;
+       xfrm_address_t          remote;
+       u32                     reserved;
+       u16                     family;
+};
+
 struct xfrm_migrate {
        xfrm_address_t          old_daddr;
        xfrm_address_t          old_saddr;
@@ -531,7 +538,7 @@ struct xfrm_mgr
        int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
        int                     (*notify_policy)(struct xfrm_policy *x, int dir, struct km_event *c);
        int                     (*report)(u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
-       int                     (*migrate)(struct xfrm_selector *sel, u8 dir, u8 type, struct xfrm_migrate *m, int num_bundles);
+       int                     (*migrate)(struct xfrm_selector *sel, u8 dir, u8 type, struct xfrm_migrate *m, int num_bundles, struct xfrm_kmaddress *k);
 };
 
 extern int xfrm_register_km(struct xfrm_mgr *km);
@@ -1432,12 +1439,14 @@ extern int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *xdst,
 
 #ifdef CONFIG_XFRM_MIGRATE
 extern int km_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                     struct xfrm_migrate *m, int num_bundles);
+                     struct xfrm_migrate *m, int num_bundles,
+                     struct xfrm_kmaddress *k);
 extern struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m);
 extern struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
                                              struct xfrm_migrate *m);
 extern int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                       struct xfrm_migrate *m, int num_bundles);
+                       struct xfrm_migrate *m, int num_bundles,
+                       struct xfrm_kmaddress *k);
 #endif
 
 extern wait_queue_head_t km_waitq;

diff --git a/net/key/af_key.c b/net/key/af_key.c
index 7ae641d..362fe31 100644 (file)
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -398,6 +398,7 @@ static u8 sadb_ext_min_len[] = {
        [SADB_X_EXT_NAT_T_DPORT]        = (u8) sizeof(struct sadb_x_nat_t_port),
        [SADB_X_EXT_NAT_T_OA]           = (u8) sizeof(struct sadb_address),
        [SADB_X_EXT_SEC_CTX]            = (u8) sizeof(struct sadb_x_sec_ctx),
+       [SADB_X_EXT_KMADDRESS]          = (u8) sizeof(struct sadb_x_kmaddress),
 };
 
 /* Verify sadb_address_{len,prefixlen} against sa_family.  */
@@ -2384,24 +2385,21 @@ static int pfkey_sockaddr_pair_size(sa_family_t family)
        return PFKEY_ALIGN8(pfkey_sockaddr_len(family) * 2);
 }
 
-static int parse_sockaddr_pair(struct sadb_x_ipsecrequest *rq,
+static int parse_sockaddr_pair(struct sockaddr *sa, int ext_len,
                               xfrm_address_t *saddr, xfrm_address_t *daddr,
                               u16 *family)
 {
-       u8 *sa = (u8 *) (rq + 1);
        int af, socklen;
 
-       if (rq->sadb_x_ipsecrequest_len <
-           pfkey_sockaddr_pair_size(((struct sockaddr *)sa)->sa_family))
+       if (ext_len < pfkey_sockaddr_pair_size(sa->sa_family))
                return -EINVAL;
 
-       af = pfkey_sockaddr_extract((struct sockaddr *) sa,
-                                   saddr);
+       af = pfkey_sockaddr_extract(sa, saddr);
        if (!af)
                return -EINVAL;
 
        socklen = pfkey_sockaddr_len(af);
-       if (pfkey_sockaddr_extract((struct sockaddr *) (sa + socklen),
+       if (pfkey_sockaddr_extract((struct sockaddr *) (((u8 *)sa) + socklen),
                                   daddr) != af)
                return -EINVAL;
 
@@ -2421,7 +2419,9 @@ static int ipsecrequests_to_migrate(struct sadb_x_ipsecrequest *rq1, int len,
                return -EINVAL;
 
        /* old endoints */
-       err = parse_sockaddr_pair(rq1, &m->old_saddr, &m->old_daddr,
+       err = parse_sockaddr_pair((struct sockaddr *)(rq1 + 1),
+                                 rq1->sadb_x_ipsecrequest_len,
+                                 &m->old_saddr, &m->old_daddr,
                                  &m->old_family);
        if (err)
                return err;
@@ -2434,7 +2434,9 @@ static int ipsecrequests_to_migrate(struct sadb_x_ipsecrequest *rq1, int len,
                return -EINVAL;
 
        /* new endpoints */
-       err = parse_sockaddr_pair(rq2, &m->new_saddr, &m->new_daddr,
+       err = parse_sockaddr_pair((struct sockaddr *)(rq2 + 1),
+                                 rq2->sadb_x_ipsecrequest_len,
+                                 &m->new_saddr, &m->new_daddr,
                                  &m->new_family);
        if (err)
                return err;
@@ -2460,29 +2462,40 @@ static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
        int i, len, ret, err = -EINVAL;
        u8 dir;
        struct sadb_address *sa;
+       struct sadb_x_kmaddress *kma;
        struct sadb_x_policy *pol;
        struct sadb_x_ipsecrequest *rq;
        struct xfrm_selector sel;
        struct xfrm_migrate m[XFRM_MAX_DEPTH];
+       struct xfrm_kmaddress k;
 
        if (!present_and_same_family(ext_hdrs[SADB_EXT_ADDRESS_SRC - 1],
-           ext_hdrs[SADB_EXT_ADDRESS_DST - 1]) ||
+                                    ext_hdrs[SADB_EXT_ADDRESS_DST - 1]) ||
            !ext_hdrs[SADB_X_EXT_POLICY - 1]) {
                err = -EINVAL;
                goto out;
        }
 
+       kma = ext_hdrs[SADB_X_EXT_KMADDRESS - 1];
        pol = ext_hdrs[SADB_X_EXT_POLICY - 1];
-       if (!pol) {
-               err = -EINVAL;
-               goto out;
-       }
 
        if (pol->sadb_x_policy_dir >= IPSEC_DIR_MAX) {
                err = -EINVAL;
                goto out;
        }
 
+       if (kma) {
+               /* convert sadb_x_kmaddress to xfrm_kmaddress */
+               k.reserved = kma->sadb_x_kmaddress_reserved;
+               ret = parse_sockaddr_pair((struct sockaddr *)(kma + 1),
+                                         8*(kma->sadb_x_kmaddress_len) - sizeof(*kma),
+                                         &k.local, &k.remote, &k.family);
+               if (ret < 0) {
+                       err = ret;
+                       goto out;
+               }
+       }
+
        dir = pol->sadb_x_policy_dir - 1;
        memset(&sel, 0, sizeof(sel));
 
@@ -2527,7 +2540,8 @@ static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
                goto out;
        }
 
-       return xfrm_migrate(&sel, dir, XFRM_POLICY_TYPE_MAIN, m, i);
+       return xfrm_migrate(&sel, dir, XFRM_POLICY_TYPE_MAIN, m, i,
+                           kma ? &k : NULL);
 
  out:
        return err;
@@ -3319,6 +3333,32 @@ static int set_sadb_address(struct sk_buff *skb, int sasize, int type,
        return 0;
 }
 
+
+static int set_sadb_kmaddress(struct sk_buff *skb, struct xfrm_kmaddress *k)
+{
+       struct sadb_x_kmaddress *kma;
+       u8 *sa;
+       int family = k->family;
+       int socklen = pfkey_sockaddr_len(family);
+       int size_req;
+
+       size_req = (sizeof(struct sadb_x_kmaddress) +
+                   pfkey_sockaddr_pair_size(family));
+
+       kma = (struct sadb_x_kmaddress *)skb_put(skb, size_req);
+       memset(kma, 0, size_req);
+       kma->sadb_x_kmaddress_len = size_req / 8;
+       kma->sadb_x_kmaddress_exttype = SADB_X_EXT_KMADDRESS;
+       kma->sadb_x_kmaddress_reserved = k->reserved;
+
+       sa = (u8 *)(kma + 1);
+       if (!pfkey_sockaddr_fill(&k->local, 0, (struct sockaddr *)sa, family) ||
+           !pfkey_sockaddr_fill(&k->remote, 0, (struct sockaddr *)(sa+socklen), family))
+               return -EINVAL;
+
+       return 0;
+}
+
 static int set_ipsecrequest(struct sk_buff *skb,
                            uint8_t proto, uint8_t mode, int level,
                            uint32_t reqid, uint8_t family,
@@ -3351,7 +3391,8 @@ static int set_ipsecrequest(struct sk_buff *skb,
 
 #ifdef CONFIG_NET_KEY_MIGRATE
 static int pfkey_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                             struct xfrm_migrate *m, int num_bundles)
+                             struct xfrm_migrate *m, int num_bundles,
+                             struct xfrm_kmaddress *k)
 {
        int i;
        int sasize_sel;
@@ -3368,6 +3409,12 @@ static int pfkey_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
        if (num_bundles <= 0 || num_bundles > XFRM_MAX_DEPTH)
                return -EINVAL;
 
+       if (k != NULL) {
+               /* addresses for KM */
+               size += PFKEY_ALIGN8(sizeof(struct sadb_x_kmaddress) +
+                                    pfkey_sockaddr_pair_size(k->family));
+       }
+
        /* selector */
        sasize_sel = pfkey_sockaddr_size(sel->family);
        if (!sasize_sel)
@@ -3404,6 +3451,10 @@ static int pfkey_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
        hdr->sadb_msg_seq = 0;
        hdr->sadb_msg_pid = 0;
 
+       /* Addresses to be used by KM for negotiation, if ext is available */
+       if (k != NULL && (set_sadb_kmaddress(skb, k) < 0))
+               return -EINVAL;
+
        /* selector src */
        set_sadb_address(skb, sasize_sel, SADB_EXT_ADDRESS_SRC, sel);
 
@@ -3449,7 +3500,8 @@ err:
 }
 #else
 static int pfkey_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                             struct xfrm_migrate *m, int num_bundles)
+                             struct xfrm_migrate *m, int num_bundles,
+                             struct xfrm_kmaddress *k)
 {
        return -ENOPROTOOPT;
 }

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index b7ec080..832b47c 100644 (file)
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2679,7 +2679,8 @@ static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
 }
 
 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                struct xfrm_migrate *m, int num_migrate)
+                struct xfrm_migrate *m, int num_migrate,
+                struct xfrm_kmaddress *k)
 {
        int i, err, nx_cur = 0, nx_new = 0;
        struct xfrm_policy *pol = NULL;
@@ -2723,7 +2724,7 @@ int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
        }
 
        /* Stage 5 - announce */
-       km_migrate(sel, dir, type, m, num_migrate);
+       km_migrate(sel, dir, type, m, num_migrate, k);
 
        xfrm_pol_put(pol);
 

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 747fd8c..508337f 100644 (file)
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1814,7 +1814,8 @@ EXPORT_SYMBOL(km_policy_expired);
 
 #ifdef CONFIG_XFRM_MIGRATE
 int km_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-              struct xfrm_migrate *m, int num_migrate)
+              struct xfrm_migrate *m, int num_migrate,
+              struct xfrm_kmaddress *k)
 {
        int err = -EINVAL;
        int ret;
@@ -1823,7 +1824,7 @@ int km_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
        read_lock(&xfrm_km_lock);
        list_for_each_entry(km, &xfrm_km_list, list) {
                if (km->migrate) {
-                       ret = km->migrate(sel, dir, type, m, num_migrate);
+                       ret = km->migrate(sel, dir, type, m, num_migrate, k);
                        if (!ret)
                                err = ret;
                }

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 76f75df..4a8a1ab 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1710,12 +1710,23 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 #ifdef CONFIG_XFRM_MIGRATE
 static int copy_from_user_migrate(struct xfrm_migrate *ma,
+                                 struct xfrm_kmaddress *k,
                                  struct nlattr **attrs, int *num)
 {
        struct nlattr *rt = attrs[XFRMA_MIGRATE];
        struct xfrm_user_migrate *um;
        int i, num_migrate;
 
+       if (k != NULL) {
+               struct xfrm_user_kmaddress *uk;
+
+               uk = nla_data(attrs[XFRMA_KMADDRESS]);
+               memcpy(&k->local, &uk->local, sizeof(k->local));
+               memcpy(&k->remote, &uk->remote, sizeof(k->remote));
+               k->family = uk->family;
+               k->reserved = uk->reserved;
+       }
+
        um = nla_data(rt);
        num_migrate = nla_len(rt) / sizeof(*um);
 
@@ -1745,6 +1756,7 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
 {
        struct xfrm_userpolicy_id *pi = nlmsg_data(nlh);
        struct xfrm_migrate m[XFRM_MAX_DEPTH];
+       struct xfrm_kmaddress km, *kmp;
        u8 type;
        int err;
        int n = 0;
@@ -1752,19 +1764,20 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
        if (attrs[XFRMA_MIGRATE] == NULL)
                return -EINVAL;
 
+       kmp = attrs[XFRMA_KMADDRESS] ? &km : NULL;
+
        err = copy_from_user_policy_type(&type, attrs);
        if (err)
                return err;
 
-       err = copy_from_user_migrate((struct xfrm_migrate *)m,
-                                    attrs, &n);
+       err = copy_from_user_migrate((struct xfrm_migrate *)m, kmp, attrs, &n);
        if (err)
                return err;
 
        if (!n)
                return 0;
 
-       xfrm_migrate(&pi->sel, pi->dir, type, m, n);
+       xfrm_migrate(&pi->sel, pi->dir, type, m, n, kmp);
 
        return 0;
 }
@@ -1795,16 +1808,30 @@ static int copy_to_user_migrate(struct xfrm_migrate *m, struct sk_buff *skb)
        return nla_put(skb, XFRMA_MIGRATE, sizeof(um), &um);
 }
 
-static inline size_t xfrm_migrate_msgsize(int num_migrate)
+static int copy_to_user_kmaddress(struct xfrm_kmaddress *k, struct sk_buff *skb)
+{
+       struct xfrm_user_kmaddress uk;
+
+       memset(&uk, 0, sizeof(uk));
+       uk.family = k->family;
+       uk.reserved = k->reserved;
+       memcpy(&uk.local, &k->local, sizeof(uk.local));
+       memcpy(&uk.remote, &k->local, sizeof(uk.remote));
+
+       return nla_put(skb, XFRMA_KMADDRESS, sizeof(uk), &uk);
+}
+
+static inline size_t xfrm_migrate_msgsize(int num_migrate, int with_kma)
 {
        return NLMSG_ALIGN(sizeof(struct xfrm_userpolicy_id))
-              + nla_total_size(sizeof(struct xfrm_user_migrate) * num_migrate)
-              + userpolicy_type_attrsize();
+             + (with_kma ? nla_total_size(sizeof(struct xfrm_kmaddress)) : 0)
+             + nla_total_size(sizeof(struct xfrm_user_migrate) * num_migrate)
+             + userpolicy_type_attrsize();
 }
 
 static int build_migrate(struct sk_buff *skb, struct xfrm_migrate *m,
-                        int num_migrate, struct xfrm_selector *sel,
-                        u8 dir, u8 type)
+                        int num_migrate, struct xfrm_kmaddress *k,
+                        struct xfrm_selector *sel, u8 dir, u8 type)
 {
        struct xfrm_migrate *mp;
        struct xfrm_userpolicy_id *pol_id;
@@ -1821,6 +1848,9 @@ static int build_migrate(struct sk_buff *skb, struct xfrm_migrate *m,
        memcpy(&pol_id->sel, sel, sizeof(pol_id->sel));
        pol_id->dir = dir;
 
+       if (k != NULL && (copy_to_user_kmaddress(k, skb) < 0))
+                       goto nlmsg_failure;
+
        if (copy_to_user_policy_type(type, skb) < 0)
                goto nlmsg_failure;
 
@@ -1836,23 +1866,25 @@ nlmsg_failure:
 }
 
 static int xfrm_send_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
-                            struct xfrm_migrate *m, int num_migrate)
+                            struct xfrm_migrate *m, int num_migrate,
+                            struct xfrm_kmaddress *k)
 {
        struct sk_buff *skb;
 
-       skb = nlmsg_new(xfrm_migrate_msgsize(num_migrate), GFP_ATOMIC);
+       skb = nlmsg_new(xfrm_migrate_msgsize(num_migrate, !!k), GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;
 
        /* build migrate */
-       if (build_migrate(skb, m, num_migrate, sel, dir, type) < 0)
+       if (build_migrate(skb, m, num_migrate, k, sel, dir, type) < 0)
                BUG();
 
        return nlmsg_multicast(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)
+                            struct xfrm_migrate *m, int num_migrate,
+                            struct xfrm_kmaddress *k)
 {
        return -ENOPROTOOPT;
 }
@@ -1901,6 +1933,7 @@ static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
        [XFRMA_COADDR]          = { .len = sizeof(xfrm_address_t) },
        [XFRMA_POLICY_TYPE]     = { .len = sizeof(struct xfrm_userpolicy_type)},
        [XFRMA_MIGRATE]         = { .len = sizeof(struct xfrm_user_migrate) },
+       [XFRMA_KMADDRESS]       = { .len = sizeof(struct xfrm_user_kmaddress) },
 };
 
 static struct xfrm_link {