Merge branch 'drm-patches' of ssh://master.kernel.org/pub/scm/linux/kernel/git/airlie...

[linux-2.6] / net / ipv4 / esp4.c

diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index bdc65d8af1813bb6f8f436567c02e658a16696f7..98767a4f1185befb14c519fb73395056066f159f 100644 (file)
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -272,32 +272,33 @@ out:
        return -EINVAL;
 }
 
-static u32 esp4_get_max_size(struct xfrm_state *x, int mtu)
+static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
 {
        struct esp_data *esp = x->data;
        u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
-       int enclen = 0;
+       u32 align = max_t(u32, blksize, esp->conf.padlen);
+       u32 rem;
+
+       mtu -= x->props.header_len + esp->auth.icv_trunc_len;
+       rem = mtu & (align - 1);
+       mtu &= ~(align - 1);
 
        switch (x->props.mode) {
        case XFRM_MODE_TUNNEL:
-               mtu = ALIGN(mtu +2, blksize);
                break;
        default:
        case XFRM_MODE_TRANSPORT:
                /* The worst case */
-               mtu = ALIGN(mtu + 2, 4) + blksize - 4;
+               mtu -= blksize - 4;
+               mtu += min_t(u32, blksize - 4, rem);
                break;
        case XFRM_MODE_BEET:
                /* The worst case. */
-               enclen = IPV4_BEET_PHMAXLEN;
-               mtu = ALIGN(mtu + enclen + 2, blksize);
+               mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem);
                break;
        }
 
-       if (esp->conf.padlen)
-               mtu = ALIGN(mtu, esp->conf.padlen);
-
-       return mtu + x->props.header_len + esp->auth.icv_trunc_len - enclen;
+       return mtu - 2;
 }
 
 static void esp4_err(struct sk_buff *skb, u32 info)
@@ -340,6 +341,7 @@ static int esp_init_state(struct xfrm_state *x)
 {
        struct esp_data *esp = NULL;
        struct crypto_blkcipher *tfm;
+       u32 align;
 
        /* null auth and encryption can have zero length keys */
        if (x->aalg) {
@@ -406,6 +408,8 @@ static int esp_init_state(struct xfrm_state *x)
        x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen;
        if (x->props.mode == XFRM_MODE_TUNNEL)
                x->props.header_len += sizeof(struct iphdr);
+       else if (x->props.mode == XFRM_MODE_BEET)
+               x->props.header_len += IPV4_BEET_PHMAXLEN;
        if (x->encap) {
                struct xfrm_encap_tmpl *encap = x->encap;
 
@@ -421,7 +425,10 @@ static int esp_init_state(struct xfrm_state *x)
                }
        }
        x->data = esp;
-       x->props.trailer_len = esp4_get_max_size(x, 0) - x->props.header_len;
+       align = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
+       if (esp->conf.padlen)
+               align = max_t(u32, align, esp->conf.padlen);
+       x->props.trailer_len = align + 1 + esp->auth.icv_trunc_len;
        return 0;
 
 error:
@@ -438,7 +445,7 @@ static struct xfrm_type esp_type =
        .proto          = IPPROTO_ESP,
        .init_state     = esp_init_state,
        .destructor     = esp_destroy,
-       .get_max_size   = esp4_get_max_size,
+       .get_mtu        = esp4_get_mtu,
        .input          = esp_input,
        .output         = esp_output
 };
@@ -474,3 +481,4 @@ static void __exit esp4_fini(void)
 module_init(esp4_init);
 module_exit(esp4_fini);
 MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);