Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=cf5cb79f6946063b04be3df16dcaa781e48bdbef
Commit:     cf5cb79f6946063b04be3df16dcaa781e48bdbef
Parent:     a7bd9a45c8c8901f800a461a4098ebae2b8a4b78
Author:     Thomas Graf <[EMAIL PROTECTED]>
AuthorDate: Wed Aug 22 13:59:04 2007 -0700
Committer:  David S. Miller <[EMAIL PROTECTED]>
CommitDate: Wed Oct 10 16:48:23 2007 -0700

    [XFRM] netlink: Establish an attribute policy
    
    Adds a policy defining the minimal payload lengths for all the attributes
    allowing for most attribute validation checks to be removed from in
    the middle of the code path. Makes updates more consistent as many format
    errors are recognised earlier, before any changes have been attempted.
    
    Signed-off-by: Thomas Graf <[EMAIL PROTECTED]>
    Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
---
 net/xfrm/xfrm_user.c |  125 ++++++++++++-------------------------------------
 1 files changed, 31 insertions(+), 94 deletions(-)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 9103af0..1371a0a 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -42,19 +42,12 @@ static int verify_one_alg(struct rtattr **xfrma, enum 
xfrm_attr_type_t type)
 {
        struct rtattr *rt = xfrma[type - 1];
        struct xfrm_algo *algp;
-       int len;
 
        if (!rt)
                return 0;
 
-       len = (rt->rta_len - sizeof(*rt)) - sizeof(*algp);
-       if (len < 0)
-               return -EINVAL;
-
        algp = RTA_DATA(rt);
-
-       len -= (algp->alg_key_len + 7U) / 8;
-       if (len < 0)
+       if (RTA_PAYLOAD(rt) < alg_len(algp))
                return -EINVAL;
 
        switch (type) {
@@ -82,55 +75,25 @@ static int verify_one_alg(struct rtattr **xfrma, enum 
xfrm_attr_type_t type)
        return 0;
 }
 
-static int verify_encap_tmpl(struct rtattr **xfrma)
-{
-       struct rtattr *rt = xfrma[XFRMA_ENCAP - 1];
-       struct xfrm_encap_tmpl *encap;
-
-       if (!rt)
-               return 0;
-
-       if ((rt->rta_len - sizeof(*rt)) < sizeof(*encap))
-               return -EINVAL;
-
-       return 0;
-}
-
-static int verify_one_addr(struct rtattr **xfrma, enum xfrm_attr_type_t type,
+static void verify_one_addr(struct rtattr **xfrma, enum xfrm_attr_type_t type,
                           xfrm_address_t **addrp)
 {
        struct rtattr *rt = xfrma[type - 1];
 
-       if (!rt)
-               return 0;
-
-       if ((rt->rta_len - sizeof(*rt)) < sizeof(**addrp))
-               return -EINVAL;
-
-       if (addrp)
+       if (rt && addrp)
                *addrp = RTA_DATA(rt);
-
-       return 0;
 }
 
 static inline int verify_sec_ctx_len(struct rtattr **xfrma)
 {
        struct rtattr *rt = xfrma[XFRMA_SEC_CTX - 1];
        struct xfrm_user_sec_ctx *uctx;
-       int len = 0;
 
        if (!rt)
                return 0;
 
-       if (rt->rta_len < sizeof(*uctx))
-               return -EINVAL;
-
        uctx = RTA_DATA(rt);
-
-       len += sizeof(struct xfrm_user_sec_ctx);
-       len += uctx->ctx_len;
-
-       if (uctx->len != len)
+       if (uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len))
                return -EINVAL;
 
        return 0;
@@ -205,12 +168,8 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
                goto out;
        if ((err = verify_one_alg(xfrma, XFRMA_ALG_COMP)))
                goto out;
-       if ((err = verify_encap_tmpl(xfrma)))
-               goto out;
        if ((err = verify_sec_ctx_len(xfrma)))
                goto out;
-       if ((err = verify_one_addr(xfrma, XFRMA_COADDR, NULL)))
-               goto out;
 
        err = -EINVAL;
        switch (p->mode) {
@@ -339,9 +298,8 @@ static void copy_from_user_state(struct xfrm_state *x, 
struct xfrm_usersa_info *
  * somehow made shareable and move it to xfrm_state.c - JHS
  *
 */
-static int xfrm_update_ae_params(struct xfrm_state *x, struct rtattr **xfrma)
+static void xfrm_update_ae_params(struct xfrm_state *x, struct rtattr **xfrma)
 {
-       int err = - EINVAL;
        struct rtattr *rp = xfrma[XFRMA_REPLAY_VAL-1];
        struct rtattr *lt = xfrma[XFRMA_LTIME_VAL-1];
        struct rtattr *et = xfrma[XFRMA_ETIMER_THRESH-1];
@@ -349,8 +307,6 @@ static int xfrm_update_ae_params(struct xfrm_state *x, 
struct rtattr **xfrma)
 
        if (rp) {
                struct xfrm_replay_state *replay;
-               if (RTA_PAYLOAD(rp) < sizeof(*replay))
-                       goto error;
                replay = RTA_DATA(rp);
                memcpy(&x->replay, replay, sizeof(*replay));
                memcpy(&x->preplay, replay, sizeof(*replay));
@@ -358,8 +314,6 @@ static int xfrm_update_ae_params(struct xfrm_state *x, 
struct rtattr **xfrma)
 
        if (lt) {
                struct xfrm_lifetime_cur *ltime;
-               if (RTA_PAYLOAD(lt) < sizeof(*ltime))
-                       goto error;
                ltime = RTA_DATA(lt);
                x->curlft.bytes = ltime->bytes;
                x->curlft.packets = ltime->packets;
@@ -367,21 +321,11 @@ static int xfrm_update_ae_params(struct xfrm_state *x, 
struct rtattr **xfrma)
                x->curlft.use_time = ltime->use_time;
        }
 
-       if (et) {
-               if (RTA_PAYLOAD(et) < sizeof(u32))
-                       goto error;
+       if (et)
                x->replay_maxage = *(u32*)RTA_DATA(et);
-       }
 
-       if (rt) {
-               if (RTA_PAYLOAD(rt) < sizeof(u32))
-                       goto error;
+       if (rt)
                x->replay_maxdiff = *(u32*)RTA_DATA(rt);
-       }
-
-       return 0;
-error:
-       return err;
 }
 
 static struct xfrm_state *xfrm_state_construct(struct xfrm_usersa_info *p,
@@ -429,9 +373,7 @@ static struct xfrm_state *xfrm_state_construct(struct 
xfrm_usersa_info *p,
 
        /* override default values from above */
 
-       err = xfrm_update_ae_params(x, (struct rtattr **)xfrma);
-       if (err < 0)
-               goto error;
+       xfrm_update_ae_params(x, (struct rtattr **)xfrma);
 
        return x;
 
@@ -497,10 +439,7 @@ static struct xfrm_state *xfrm_user_state_lookup(struct 
xfrm_usersa_id *p,
        } else {
                xfrm_address_t *saddr = NULL;
 
-               err = verify_one_addr(xfrma, XFRMA_SRCADDR, &saddr);
-               if (err)
-                       goto out;
-
+               verify_one_addr(xfrma, XFRMA_SRCADDR, &saddr);
                if (!saddr) {
                        err = -EINVAL;
                        goto out;
@@ -1072,9 +1011,6 @@ static int copy_from_user_policy_type(u8 *tp, struct 
rtattr **xfrma)
        int err;
 
        if (rt) {
-               if (rt->rta_len < sizeof(*upt))
-                       return -EINVAL;
-
                upt = RTA_DATA(rt);
                type = upt->type;
        }
@@ -1537,10 +1473,8 @@ static int xfrm_new_ae(struct sk_buff *skb, struct 
nlmsghdr *nlh,
                goto out;
 
        spin_lock_bh(&x->lock);
-       err = xfrm_update_ae_params(x, xfrma);
+       xfrm_update_ae_params(x, xfrma);
        spin_unlock_bh(&x->lock);
-       if (err < 0)
-               goto out;
 
        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;
@@ -1726,20 +1660,6 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct 
nlmsghdr *nlh,
 }
 
 #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)
 {
@@ -1780,9 +1700,8 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct 
nlmsghdr *nlh,
        int err;
        int n = 0;
 
-       err = verify_user_migrate((struct rtattr **)xfrma);
-       if (err)
-               return err;
+       if (xfrma[XFRMA_MIGRATE-1] == NULL)
+               return -EINVAL;
 
        err = copy_from_user_policy_type(&type, (struct rtattr **)xfrma);
        if (err)
@@ -1917,6 +1836,23 @@ static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
 
 #undef XMSGSIZE
 
+static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
+       [XFRMA_ALG_AUTH]        = { .len = sizeof(struct xfrm_algo) },
+       [XFRMA_ALG_CRYPT]       = { .len = sizeof(struct xfrm_algo) },
+       [XFRMA_ALG_COMP]        = { .len = sizeof(struct xfrm_algo) },
+       [XFRMA_ENCAP]           = { .len = sizeof(struct xfrm_encap_tmpl) },
+       [XFRMA_TMPL]            = { .len = sizeof(struct xfrm_user_tmpl) },
+       [XFRMA_SEC_CTX]         = { .len = sizeof(struct xfrm_sec_ctx) },
+       [XFRMA_LTIME_VAL]       = { .len = sizeof(struct xfrm_lifetime_cur) },
+       [XFRMA_REPLAY_VAL]      = { .len = sizeof(struct xfrm_replay_state) },
+       [XFRMA_REPLAY_THRESH]   = { .type = NLA_U32 },
+       [XFRMA_ETIMER_THRESH]   = { .type = NLA_U32 },
+       [XFRMA_SRCADDR]         = { .len = sizeof(xfrm_address_t) },
+       [XFRMA_COADDR]          = { .len = sizeof(xfrm_address_t) },
+       [XFRMA_POLICY_TYPE]     = { .len = sizeof(struct xfrm_userpolicy_type)},
+       [XFRMA_MIGRATE]         = { .len = sizeof(struct xfrm_user_migrate) },
+};
+
 static struct xfrm_link {
        int (*doit)(struct sk_buff *, struct nlmsghdr *, struct rtattr **);
        int (*dump)(struct sk_buff *, struct netlink_callback *);
@@ -1972,7 +1908,8 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct 
nlmsghdr *nlh)
 
        /* FIXME: Temporary hack, nlmsg_parse() starts at xfrma[1], old code
         * expects first attribute at xfrma[0] */
-       err = nlmsg_parse(nlh, xfrm_msg_min[type], xfrma-1, XFRMA_MAX, NULL);
+       err = nlmsg_parse(nlh, xfrm_msg_min[type], xfrma-1, XFRMA_MAX,
+                         xfrma_policy);
        if (err < 0)
                return err;
 
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to