[IPSEC] ESP: Use block ciphers where applicable

This patch converts IPSec/ESP to use the new block cipher type where
applicable.  Similar to the HMAC conversion, existing algorithm names
have been kept for compatibility.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

2 files changed, 30 insertions, 20 deletions

diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 8514106761b0..3b5d504a74be 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -386,6 +386,7 @@ config INET_ESP
         select CRYPTO
         select CRYPTO_HMAC
         select CRYPTO_MD5
+        select CRYPTO_CBC
         select CRYPTO_SHA1
         select CRYPTO_DES
         ---help---
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index fc2f8ce441de..7c63ae494742 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -1,3 +1,4 @@
+#include <linux/err.h>
 #include <linux/module.h>
 #include <net/ip.h>
 #include <net/xfrm.h>
@@ -16,7 +17,8 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
         int err;
         struct iphdr *top_iph;
         struct ip_esp_hdr *esph;
-        struct crypto_tfm *tfm;
+        struct crypto_blkcipher *tfm;
+        struct blkcipher_desc desc;
         struct esp_data *esp;
         struct sk_buff *trailer;
         int blksize;
@@ -36,7 +38,9 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
         esp = x->data;
         alen = esp->auth.icv_trunc_len;
         tfm = esp->conf.tfm;
-        blksize = ALIGN(crypto_tfm_alg_blocksize(tfm), 4);
+        desc.tfm = tfm;
+        desc.flags = 0;
+        blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
         clen = ALIGN(clen + 2, blksize);
         if (esp->conf.padlen)
                 clen = ALIGN(clen, esp->conf.padlen);
@@ -92,7 +96,7 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
         xfrm_aevent_doreplay(x);
 
         if (esp->conf.ivlen)
-                crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
+                crypto_blkcipher_set_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
 
         do {
                 struct scatterlist *sg = &esp->sgbuf[0];
@@ -103,14 +107,17 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
                                 goto error;
                 }
                 skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen);
-                crypto_cipher_encrypt(tfm, sg, sg, clen);
+                err = crypto_blkcipher_encrypt(&desc, sg, sg, clen);
                 if (unlikely(sg != &esp->sgbuf[0]))
                         kfree(sg);
         } while (0);
 
+        if (unlikely(err))
+                goto error;
+
         if (esp->conf.ivlen) {
-                memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
-                crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
+                memcpy(esph->enc_data, esp->conf.ivec, esp->conf.ivlen);
+                crypto_blkcipher_get_iv(tfm, esp->conf.ivec, esp->conf.ivlen);
         }
 
         if (esp->auth.icv_full_len) {
@@ -121,8 +128,6 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 
         ip_send_check(top_iph);
 
-        err = 0;
-
 error:
         return err;
 }
@@ -137,8 +142,10 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
         struct iphdr *iph;
         struct ip_esp_hdr *esph;
         struct esp_data *esp = x->data;
+        struct crypto_blkcipher *tfm = esp->conf.tfm;
+        struct blkcipher_desc desc = { .tfm = tfm };
         struct sk_buff *trailer;
-        int blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4);
+        int blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
         int alen = esp->auth.icv_trunc_len;
         int elen = skb->len - sizeof(struct ip_esp_hdr) - esp->conf.ivlen - alen;
         int nfrags;
@@ -146,6 +153,7 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
         u8 nexthdr[2];
         struct scatterlist *sg;
         int padlen;
+        int err;
 
         if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr)))
                 goto out;
@@ -178,7 +186,7 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
 
         /* Get ivec. This can be wrong, check against another impls. */
         if (esp->conf.ivlen)
-                crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm));
+                crypto_blkcipher_set_iv(tfm, esph->enc_data, esp->conf.ivlen);
 
         sg = &esp->sgbuf[0];
 
@@ -188,9 +196,11 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
                         goto out;
         }
         skb_to_sgvec(skb, sg, sizeof(struct ip_esp_hdr) + esp->conf.ivlen, elen);
-        crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen);
+        err = crypto_blkcipher_decrypt(&desc, sg, sg, elen);
         if (unlikely(sg != &esp->sgbuf[0]))
                 kfree(sg);
+        if (unlikely(err))
+                return err;
 
         if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
                 BUG();
@@ -254,7 +264,7 @@ out:
 static u32 esp4_get_max_size(struct xfrm_state *x, int mtu)
 {
         struct esp_data *esp = x->data;
-        u32 blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4);
+        u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
 
         if (x->props.mode) {
                 mtu = ALIGN(mtu + 2, blksize);
@@ -293,7 +303,7 @@ static void esp_destroy(struct xfrm_state *x)
         if (!esp)
                 return;
 
-        crypto_free_tfm(esp->conf.tfm);
+        crypto_free_blkcipher(esp->conf.tfm);
         esp->conf.tfm = NULL;
         kfree(esp->conf.ivec);
         esp->conf.ivec = NULL;
@@ -307,6 +317,7 @@ static void esp_destroy(struct xfrm_state *x)
 static int esp_init_state(struct xfrm_state *x)
 {
         struct esp_data *esp = NULL;
+        struct crypto_blkcipher *tfm;
 
         /* null auth and encryption can have zero length keys */
         if (x->aalg) {
@@ -351,13 +362,11 @@ static int esp_init_state(struct xfrm_state *x)
         }
         esp->conf.key = x->ealg->alg_key;
         esp->conf.key_len = (x->ealg->alg_key_len+7)/8;
-        if (x->props.ealgo == SADB_EALG_NULL)
-                esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_ECB);
-        else
-                esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_CBC);
-        if (esp->conf.tfm == NULL)
+        tfm = crypto_alloc_blkcipher(x->ealg->alg_name, 0, CRYPTO_ALG_ASYNC);
+        if (IS_ERR(tfm))
                 goto error;
-        esp->conf.ivlen = crypto_tfm_alg_ivsize(esp->conf.tfm);
+        esp->conf.tfm = tfm;
+        esp->conf.ivlen = crypto_blkcipher_ivsize(tfm);
         esp->conf.padlen = 0;
         if (esp->conf.ivlen) {
                 esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL);
@@ -365,7 +374,7 @@ static int esp_init_state(struct xfrm_state *x)
                         goto error;
                 get_random_bytes(esp->conf.ivec, esp->conf.ivlen);
         }
-        if (crypto_cipher_setkey(esp->conf.tfm, esp->conf.key, esp->conf.key_len))
+        if (crypto_blkcipher_setkey(tfm, esp->conf.key, esp->conf.key_len))
                 goto error;
         x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen;
         if (x->props.mode)