[CRYPTO]: Cleanups and more consistency checks.

- Removed local_bh_disable() from kmap wrapper, not needed now with
two atomic kmaps.
- Nuked atomic flag, use in_softirq() instead.
- Converted crypto_kmap() and crypto_yield() to check in_softirq().
- Check CRYPTO_MAX_CIPHER_BLOCK_SIZE during alg init.
- Try to initialize as much at compile time as possible
(feedback from Christoph Hellwig).
- Clean up list handling a bit (feedback from Christoph Hellwig).

crypto/api.c

@@ -23,7 +23,7 @@
 #include "internal.h"
 
 static LIST_HEAD(crypto_alg_list);
-static struct rw_semaphore crypto_alg_sem;
+static DECLARE_RWSEM(crypto_alg_sem);
 
 static inline int crypto_alg_get(struct crypto_alg *alg)
 {
@@ -38,17 +38,12 @@ static inline void crypto_alg_put(struct crypto_alg *alg)
 
 struct crypto_alg *crypto_alg_lookup(char *name)
 {
-	struct list_head *p;
-	struct crypto_alg *alg = NULL;
+	struct crypto_alg *q, *alg = NULL;
 	
 	down_read(&crypto_alg_sem);
 	
-	list_for_each(p, &crypto_alg_list) {
-		struct crypto_alg *q =
-			list_entry(p, struct crypto_alg, cra_list);
-
+	list_for_each_entry(q, &crypto_alg_list, cra_list) {
 		if (!(strcmp(q->cra_name, name))) {
-
 			if (crypto_alg_get(q))
 				alg = q;
 			break;
@@ -63,9 +58,6 @@ static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
 {
 	tfm->crt_flags = 0;
 	
-	if (flags & CRYPTO_TFM_REQ_ATOMIC)
-		tfm->crt_flags |= CRYPTO_TFM_REQ_ATOMIC;
-	
 	switch (crypto_tfm_alg_type(tfm)) {
 	case CRYPTO_ALG_TYPE_CIPHER:
 		return crypto_init_cipher_flags(tfm, flags);
@@ -164,22 +156,34 @@ void crypto_free_tfm(struct crypto_tfm *tfm)
 	kfree(tfm);
 }
 
+static inline int crypto_alg_blocksize_check(struct crypto_alg *alg)
+{
+	return ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK)
+			== CRYPTO_ALG_TYPE_CIPHER &&
+	         alg->cra_blocksize > CRYPTO_MAX_CIPHER_BLOCK_SIZE);
+}
+
 int crypto_register_alg(struct crypto_alg *alg)
 {
 	int ret = 0;
-	struct list_head *p;
+	struct crypto_alg *q;
 	
 	down_write(&crypto_alg_sem);
 	
-	list_for_each(p, &crypto_alg_list) {
-		struct crypto_alg *q =
-			list_entry(p, struct crypto_alg, cra_list);
-		
+	list_for_each_entry(q, &crypto_alg_list, cra_list) {
 		if (!(strcmp(q->cra_name, alg->cra_name))) {
 			ret = -EEXIST;
 			goto out;
 		}
 	}
+	
+	if (crypto_alg_blocksize_check(alg)) {
+		printk(KERN_WARNING "%s: blocksize %Zd exceeds max. "
+		       "size %Zd\n", __FUNCTION__, alg->cra_blocksize,
+		       CRYPTO_MAX_CIPHER_BLOCK_SIZE);
+		ret = -EINVAL;
+	}
+	else
 		list_add_tail(&alg->cra_list, &crypto_alg_list);
 out:	
 	up_write(&crypto_alg_sem);
@@ -189,14 +193,14 @@ int crypto_register_alg(struct crypto_alg *alg)
 int crypto_unregister_alg(struct crypto_alg *alg)
 {
 	int ret = -ENOENT;
-	struct list_head *p;
+	struct crypto_alg *q;
 	
 	BUG_ON(!alg->cra_module);
 	
 	down_write(&crypto_alg_sem);
-	list_for_each(p, &crypto_alg_list) {
-		if (alg == (void *)p) {
-			list_del(p);
+	list_for_each_entry(q, &crypto_alg_list, cra_list) {
+		if (alg == q) {
+			list_del(&alg->cra_list);
 			ret = 0;
 			goto out;
 		}
@@ -282,7 +286,6 @@ static int __init init_crypto(void)
 	struct proc_dir_entry *proc;
 	
 	printk(KERN_INFO "Initializing Cryptographic API\n");
-	init_rwsem(&crypto_alg_sem);
 	proc = create_proc_entry("crypto", 0, NULL);
 	if (proc)
 		proc->proc_fops = &proc_crypto_ops;

crypto/cipher.c

@@ -71,14 +71,14 @@ static int copy_chunks(struct crypto_tfm *tfm, u8 *buf,
 			clen = rlen;
 		}
 
-		p = crypto_kmap(tfm, sg[i].page) + sg[i].offset + coff;
+		p = crypto_kmap(sg[i].page) + sg[i].offset + coff;
 		
 		if (in)
 			memcpy(&buf[copied], p, clen);
 		else
 			memcpy(p, &buf[copied], clen);
 		
-		crypto_kunmap(tfm, p);
+		crypto_kunmap(p);
 		*last = aligned ? 0 : clen;
 		copied += clen;
 	}
@@ -118,7 +118,7 @@ static int crypt(struct crypto_tfm *tfm, struct scatterlist *sg,
 {
 	int i, coff;
 	size_t bsize = crypto_tfm_alg_blocksize(tfm);
-	u8 tmp[CRYPTO_MAX_BLOCK_SIZE];
+	u8 tmp[CRYPTO_MAX_CIPHER_BLOCK_SIZE];
 
 	if (sglen(sg, nsg) % bsize) {
 		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
@@ -128,11 +128,11 @@ static int crypt(struct crypto_tfm *tfm, struct scatterlist *sg,
 	for (i = 0, coff = 0; i < nsg; i++) {
 		int n = 0, boff = 0;
 		int len = sg[i].length - coff;
-		char *p = crypto_kmap(tfm, sg[i].page) + sg[i].offset + coff;
+		char *p = crypto_kmap(sg[i].page) + sg[i].offset + coff;
 
 		while (len) {
 			if (len < bsize) {
-				crypto_kunmap(tfm, p);
+				crypto_kunmap(p);
 				n = gather_chunks(tfm, tmp, sg, i, len, &coff);
 				prfn(tfm, tmp, crfn, enc);
 				scatter_chunks(tfm, tmp, sg, i, len, &coff);
@@ -140,12 +140,12 @@ static int crypt(struct crypto_tfm *tfm, struct scatterlist *sg,
 				goto unmapped;
 			} else {
 				prfn(tfm, p, crfn, enc);
-				crypto_kunmap(tfm, p);
+				crypto_kunmap(p);
 				crypto_yield(tfm);
 				
 				/* remap and point to recalculated offset */
 				boff += bsize;
-				p = crypto_kmap(tfm, sg[i].page)
+				p = crypto_kmap(sg[i].page)
 				    + sg[i].offset + coff + boff;
 				
 				len -= bsize;
@@ -155,7 +155,7 @@ static int crypt(struct crypto_tfm *tfm, struct scatterlist *sg,
 					coff = 0;
 			}
 		}
-		crypto_kunmap(tfm, p);	
+		crypto_kunmap(p);	
 unmapped:
 		i += n;
 
@@ -172,7 +172,7 @@ static void cbc_process(struct crypto_tfm *tfm,
 		memcpy(tfm->crt_cipher.cit_iv, block,
 		       crypto_tfm_alg_blocksize(tfm));
 	} else {
-		u8 buf[CRYPTO_MAX_BLOCK_SIZE];
+		u8 buf[CRYPTO_MAX_CIPHER_BLOCK_SIZE];
 		
 		fn(tfm->crt_ctx, buf, block);
 		xor_64(buf, tfm->crt_cipher.cit_iv);

crypto/des.c

@@ -1260,6 +1260,7 @@ static struct crypto_alg des_alg = {
 	.cra_blocksize	=	DES_BLOCK_SIZE,
 	.cra_ctxsize	=	sizeof(struct des_ctx),
 	.cra_module	=	THIS_MODULE,
+	.cra_list	=	LIST_HEAD_INIT(des_alg.cra_list),
 	.cra_u		=	{ .cipher = {
 	.cia_keysize	=	DES_KEY_SIZE,
 	.cia_ivsize	=	DES_BLOCK_SIZE,
@@ -1274,6 +1275,7 @@ static struct crypto_alg des3_ede_alg = {
 	.cra_blocksize	=	DES3_EDE_BLOCK_SIZE,
 	.cra_ctxsize	=	sizeof(struct des3_ede_ctx),
 	.cra_module	=	THIS_MODULE,
+	.cra_list	=	LIST_HEAD_INIT(des3_ede_alg.cra_list),
 	.cra_u		=	{ .cipher = {
 	.cia_keysize	=	DES3_EDE_KEY_SIZE,
 	.cia_ivsize	=	DES3_EDE_BLOCK_SIZE,
@@ -1286,9 +1288,6 @@ static int __init init(void)
 {
 	int ret = 0;
 	
-	INIT_LIST_HEAD(&des_alg.cra_list);
-	INIT_LIST_HEAD(&des3_ede_alg.cra_list);
-	
 	ret = crypto_register_alg(&des_alg);
 	if (ret < 0)
 		goto out;

crypto/digest.c

@@ -34,10 +34,10 @@ static void update(struct crypto_tfm *tfm, struct scatterlist *sg, size_t nsg)
 	int i;
 	
 	for (i = 0; i < nsg; i++) {
-		char *p = crypto_kmap(tfm, sg[i].page) + sg[i].offset;
+		char *p = crypto_kmap(sg[i].page) + sg[i].offset;
 		tfm->__crt_alg->cra_digest.dia_update(tfm->crt_ctx,
 		                                      p, sg[i].length);
-		crypto_kunmap(tfm, p);
+		crypto_kunmap(p);
 		crypto_yield(tfm);
 	}
 	return;
@@ -57,10 +57,10 @@ static void digest(struct crypto_tfm *tfm,
 	tfm->crt_digest.dit_init(tfm);
 		
 	for (i = 0; i < nsg; i++) {
-		char *p = crypto_kmap(tfm, sg[i].page) + sg[i].offset;
+		char *p = crypto_kmap(sg[i].page) + sg[i].offset;
 		tfm->__crt_alg->cra_digest.dia_update(tfm->crt_ctx,
 		                                      p, sg[i].length);
-		crypto_kunmap(tfm, p);
+		crypto_kunmap(p);
 		crypto_yield(tfm);
 	}
 	crypto_digest_final(tfm, out);

crypto/internal.h

@@ -17,31 +17,21 @@
 #include <asm/hardirq.h>
 #include <asm/softirq.h>
 
-static inline void *crypto_kmap(struct crypto_tfm *tfm, struct page *page)
+static inline void *crypto_kmap(struct page *page)
 {
-	if (tfm->crt_flags & CRYPTO_TFM_REQ_ATOMIC) {
-#ifdef CONFIG_HIGHMEM	/* XXX: remove this after the api change */
-		local_bh_disable();
-#endif
-		return kmap_atomic(page, KM_CRYPTO_SOFTIRQ);
-	} else
-		return kmap_atomic(page, KM_CRYPTO_USER);
+	return kmap_atomic(page, in_softirq() ?
+	                   KM_CRYPTO_SOFTIRQ : KM_CRYPTO_USER);
 }
 
-static inline void crypto_kunmap(struct crypto_tfm *tfm, void *vaddr)
+static inline void crypto_kunmap(void *vaddr)
 {
-	if (tfm->crt_flags & CRYPTO_TFM_REQ_ATOMIC) {
-		kunmap_atomic(vaddr, KM_CRYPTO_SOFTIRQ);
-#ifdef CONFIG_HIGHMEM	/* XXX: remove this after the api change */
-		local_bh_enable();
-#endif
-	} else
-		kunmap_atomic(vaddr, KM_CRYPTO_USER);
+	return kunmap_atomic(vaddr, in_softirq() ?
+	                     KM_CRYPTO_SOFTIRQ : KM_CRYPTO_USER);
 }
 
 static inline void crypto_yield(struct crypto_tfm *tfm)
 {
-	if (!(tfm->crt_flags & CRYPTO_TFM_REQ_ATOMIC))
+	if (!in_softirq())
 		cond_resched();
 }
 

crypto/md4.c

@@ -226,6 +226,7 @@ static struct crypto_alg alg = {
 	.cra_blocksize	=	MD4_HMAC_BLOCK_SIZE,
 	.cra_ctxsize	=	sizeof(struct md4_ctx),
 	.cra_module	=	THIS_MODULE,
+	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),	
 	.cra_u		=	{ .digest = {
 	.dia_digestsize	=	MD4_DIGEST_SIZE,
 	.dia_init   	= 	md4_init,
@@ -235,7 +236,6 @@ static struct crypto_alg alg = {
 
 static int __init init(void)
 {
-	INIT_LIST_HEAD(&alg.cra_list);
 	return crypto_register_alg(&alg);
 }
 

crypto/md5.c

@@ -219,6 +219,7 @@ static struct crypto_alg alg = {
 	.cra_blocksize	=	MD5_HMAC_BLOCK_SIZE,
 	.cra_ctxsize	=	sizeof(struct md5_ctx),
 	.cra_module	=	THIS_MODULE,
+	.cra_list	=	LIST_HEAD_INIT(alg.cra_list),
 	.cra_u		=	{ .digest = {
 	.dia_digestsize	=	MD5_DIGEST_SIZE,
 	.dia_init   	= 	md5_init,
@@ -228,7 +229,6 @@ static struct crypto_alg alg = {
 
 static int __init init(void)
 {
-	INIT_LIST_HEAD(&alg.cra_list);
 	return crypto_register_alg(&alg);
 }
 

crypto/sha1.c

@@ -183,6 +183,7 @@ static struct crypto_alg alg = {
 	.cra_blocksize	=	SHA1_HMAC_BLOCK_SIZE,
 	.cra_ctxsize	=	sizeof(struct sha1_ctx),
 	.cra_module	=	THIS_MODULE,
+	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),
 	.cra_u		=	{ .digest = {
 	.dia_digestsize	=	SHA1_DIGEST_SIZE,
 	.dia_init   	= 	sha1_init,
@@ -192,7 +193,6 @@ static struct crypto_alg alg = {
 
 static int __init init(void)
 {
-	INIT_LIST_HEAD(&alg.cra_list);
 	return crypto_register_alg(&alg);
 }
 

crypto/tcrypt.c

@@ -739,7 +739,7 @@ test_des(void)
 	 */
 	i = 7;
 	key = des_tv[i].key;
-	tfm->crt_flags = CRYPTO_TFM_REQ_ATOMIC;
+	tfm->crt_flags = 0;
 
 	ret = crypto_cipher_setkey(tfm, key, 8);
 	if (ret) {
@@ -985,7 +985,6 @@ test_des(void)
 	for (i = 0; i < DES_CBC_ENC_TEST_VECTORS; i++) {
 		printk("test %d:\n", i + 1);
 
-		tfm->crt_flags |= CRYPTO_TFM_REQ_ATOMIC;
 		key = des_tv[i].key;
 
 		ret = crypto_cipher_setkey(tfm, key, 8);

include/linux/crypto.h

@@ -37,8 +37,7 @@
 #define CRYPTO_TFM_MODE_CFB		0x00000004
 #define CRYPTO_TFM_MODE_CTR		0x00000008
 
-#define CRYPTO_TFM_REQ_ATOMIC		0x00000100
-#define CRYPTO_TFM_REQ_WEAK_KEY		0x00000200
+#define CRYPTO_TFM_REQ_WEAK_KEY		0x00000100
 
 #define CRYPTO_TFM_RES_WEAK_KEY		0x00100000
 #define CRYPTO_TFM_RES_BAD_KEY_LEN   	0x00200000
@@ -52,7 +51,7 @@
  */
 #define CRYPTO_UNSPEC			0
 #define CRYPTO_MAX_ALG_NAME		64
-#define CRYPTO_MAX_BLOCK_SIZE		16
+#define CRYPTO_MAX_CIPHER_BLOCK_SIZE	16
 
 struct scatterlist;