nfsd: use SHA-256 library API instead of crypto_shash API

From: Eric Biggers <[email protected]>

This user of SHA-256 does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use.

Signed-off-by Eric Biggers <[email protected]>

---
 fs/nfsd/Kconfig       |  2 +-
 fs/nfsd/nfs4recover.c | 57 ++++++++-----------------------------------
 2 files changed, 11 insertions(+), 48 deletions(-)

fs/nfsd/Kconfig +1 -1

index 731a88f6313eb..879e0b104d1c8 100644
@@ -75,12 +75,12 @@ config NFSD_V4
 	bool "NFS server support for NFS version 4"
 	depends on NFSD && PROC_FS
 	select FS_POSIX_ACL
 	select RPCSEC_GSS_KRB5
 	select CRYPTO
+	select CRYPTO_LIB_SHA256
 	select CRYPTO_MD5
-	select CRYPTO_SHA256
 	select GRACE_PERIOD
 	select NFS_V4_2_SSC_HELPER if NFS_V4_2
 	help
 	  This option enables support in your system's NFS server for
 	  version 4 of the NFS protocol (RFC 3530).

fs/nfsd/nfs4recover.c +10 -47

index acde3edab7336..c3840793261be 100644
@@ -31,10 +31,11 @@
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
 
 #include <crypto/hash.h>
+#include <crypto/sha2.h>
 #include <linux/file.h>
 #include <linux/slab.h>
 #include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/fs.h>

@@ -735,11 +736,10 @@ static const struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 struct cld_net {
 	struct rpc_pipe		*cn_pipe;
 	spinlock_t		 cn_lock;
 	struct list_head	 cn_list;
 	unsigned int		 cn_xid;
-	struct crypto_shash	*cn_tfm;
 #ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 	bool			 cn_has_legacy;
 #endif
 };
 

@@ -1061,12 +1061,10 @@ nfsd4_remove_cld_pipe(struct net *net)
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
 
 	nfsd4_cld_unregister_net(net, cn->cn_pipe);
 	rpc_destroy_pipe_data(cn->cn_pipe);
-	if (cn->cn_tfm)
-		crypto_free_shash(cn->cn_tfm);
 	kfree(nn->cld_net);
 	nn->cld_net = NULL;
 }
 
 static struct cld_upcall *

@@ -1156,12 +1154,10 @@ nfsd4_cld_create_v2(struct nfs4_client *clp)
 	int ret;
 	struct cld_upcall *cup;
 	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
 	struct cld_msg_v2 *cmsg;
-	struct crypto_shash *tfm = cn->cn_tfm;
-	struct xdr_netobj cksum;
 	char *principal = NULL;
 
 	/* Don't upcall if it's already stored */
 	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 		return;

@@ -1180,36 +1176,22 @@ nfsd4_cld_create_v2(struct nfs4_client *clp)
 	if (clp->cl_cred.cr_raw_principal)
 		principal = clp->cl_cred.cr_raw_principal;
 	else if (clp->cl_cred.cr_principal)
 		principal = clp->cl_cred.cr_principal;
 	if (principal) {
-		cksum.len = crypto_shash_digestsize(tfm);
-		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
-		if (cksum.data == NULL) {
-			ret = -ENOMEM;
-			goto out;
-		}
-		ret = crypto_shash_tfm_digest(tfm, principal, strlen(principal),
-					      cksum.data);
-		if (ret) {
-			kfree(cksum.data);
-			goto out;
-		}
-		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = cksum.len;
-		memcpy(cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data,
-		       cksum.data, cksum.len);
-		kfree(cksum.data);
+		sha256(principal, strlen(principal),
+		       cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data);
+		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = SHA256_DIGEST_SIZE;
 	} else
 		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = 0;
 
 	ret = cld_pipe_upcall(cn->cn_pipe, cmsg, nn);
 	if (!ret) {
 		ret = cmsg->cm_status;
 		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 	}
 
-out:
 	free_cld_upcall(cup);
 out_err:
 	if (ret)
 		pr_err("NFSD: Unable to create client record on stable storage: %d\n",
 				ret);

@@ -1347,13 +1329,10 @@ static int
 nfsd4_cld_check_v2(struct nfs4_client *clp)
 {
 	struct nfs4_client_reclaim *crp;
 	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
-	int status;
-	struct crypto_shash *tfm = cn->cn_tfm;
-	struct xdr_netobj cksum;
 	char *principal = NULL;
 
 	/* did we already find that this client is stable? */
 	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 		return 0;

@@ -1365,10 +1344,11 @@ nfsd4_cld_check_v2(struct nfs4_client *clp)
 
 #ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 	if (cn->cn_has_legacy) {
 		struct xdr_netobj name;
 		char dname[HEXDIR_LEN];
+		int status;
 
 		status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 		if (status)
 			return -ENOENT;
 

@@ -1387,32 +1367,22 @@ nfsd4_cld_check_v2(struct nfs4_client *clp)
 	}
 #endif
 	return -ENOENT;
 found:
 	if (crp->cr_princhash.len) {
+		u8 digest[SHA256_DIGEST_SIZE];
+
 		if (clp->cl_cred.cr_raw_principal)
 			principal = clp->cl_cred.cr_raw_principal;
 		else if (clp->cl_cred.cr_principal)
 			principal = clp->cl_cred.cr_principal;
 		if (principal == NULL)
 			return -ENOENT;
-		cksum.len = crypto_shash_digestsize(tfm);
-		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
-		if (cksum.data == NULL)
-			return -ENOENT;
-		status = crypto_shash_tfm_digest(tfm, principal,
-						 strlen(principal), cksum.data);
-		if (status) {
-			kfree(cksum.data);
+		sha256(principal, strlen(principal), digest);
+		if (memcmp(crp->cr_princhash.data, digest,
+				crp->cr_princhash.len))
 			return -ENOENT;
-		}
-		if (memcmp(crp->cr_princhash.data, cksum.data,
-				crp->cr_princhash.len)) {
-			kfree(cksum.data);
-			return -ENOENT;
-		}
-		kfree(cksum.data);
 	}
 	crp->cr_clp = clp;
 	return 0;
 }
 

@@ -1588,11 +1558,10 @@ nfsd4_cld_tracking_init(struct net *net)
 {
 	int status;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 	bool running;
 	int retries = 10;
-	struct crypto_shash *tfm;
 
 	status = nfs4_cld_state_init(net);
 	if (status)
 		return status;
 

@@ -1613,16 +1582,10 @@ nfsd4_cld_tracking_init(struct net *net)
 
 	if (!running) {
 		status = -ETIMEDOUT;
 		goto err_remove;
 	}
-	tfm = crypto_alloc_shash("sha256", 0, 0);
-	if (IS_ERR(tfm)) {
-		status = PTR_ERR(tfm);
-		goto err_remove;
-	}
-	nn->cld_net->cn_tfm = tfm;
 
 	status = nfsd4_cld_get_version(nn);
 	if (status == -EOPNOTSUPP)
 		pr_warn("NFSD: nfsdcld GetVersion upcall failed. Please upgrade nfsdcld.\n");
 

base-commit: 33035b665157558254b3c21c3f049fd728e72368

Quoted 213 lines · Eric Biggers

From: Eric Biggers <[email protected]>

This user of SHA-256 does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use.

Signed-off-by Eric Biggers <[email protected]>

---
 fs/nfsd/Kconfig       |  2 +-
 fs/nfsd/nfs4recover.c | 57 ++++++++-----------------------------------
 2 files changed, 11 insertions(+), 48 deletions(-)

fs/nfsd/Kconfig +1 -1

index 731a88f6313eb..879e0b104d1c8 100644
@@ -75,12 +75,12 @@ config NFSD_V4
 	bool "NFS server support for NFS version 4"
 	depends on NFSD && PROC_FS
 	select FS_POSIX_ACL
 	select RPCSEC_GSS_KRB5
 	select CRYPTO
+	select CRYPTO_LIB_SHA256
 	select CRYPTO_MD5
-	select CRYPTO_SHA256
 	select GRACE_PERIOD
 	select NFS_V4_2_SSC_HELPER if NFS_V4_2
 	help
 	  This option enables support in your system's NFS server for
 	  version 4 of the NFS protocol (RFC 3530).

fs/nfsd/nfs4recover.c +10 -47

index acde3edab7336..c3840793261be 100644
@@ -31,10 +31,11 @@
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
 
 #include <crypto/hash.h>
+#include <crypto/sha2.h>
 #include <linux/file.h>
 #include <linux/slab.h>
 #include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/fs.h>

@@ -735,11 +736,10 @@ static const struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 struct cld_net {
 	struct rpc_pipe		*cn_pipe;
 	spinlock_t		 cn_lock;
 	struct list_head	 cn_list;
 	unsigned int		 cn_xid;
-	struct crypto_shash	*cn_tfm;
 #ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 	bool			 cn_has_legacy;
 #endif
 };
 

@@ -1061,12 +1061,10 @@ nfsd4_remove_cld_pipe(struct net *net)
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
 
 	nfsd4_cld_unregister_net(net, cn->cn_pipe);
 	rpc_destroy_pipe_data(cn->cn_pipe);
-	if (cn->cn_tfm)
-		crypto_free_shash(cn->cn_tfm);
 	kfree(nn->cld_net);
 	nn->cld_net = NULL;
 }
 
 static struct cld_upcall *

@@ -1156,12 +1154,10 @@ nfsd4_cld_create_v2(struct nfs4_client *clp)
 	int ret;
 	struct cld_upcall *cup;
 	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
 	struct cld_msg_v2 *cmsg;
-	struct crypto_shash *tfm = cn->cn_tfm;
-	struct xdr_netobj cksum;
 	char *principal = NULL;
 
 	/* Don't upcall if it's already stored */
 	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 		return;

@@ -1180,36 +1176,22 @@ nfsd4_cld_create_v2(struct nfs4_client *clp)
 	if (clp->cl_cred.cr_raw_principal)
 		principal = clp->cl_cred.cr_raw_principal;
 	else if (clp->cl_cred.cr_principal)
 		principal = clp->cl_cred.cr_principal;
 	if (principal) {
-		cksum.len = crypto_shash_digestsize(tfm);
-		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
-		if (cksum.data == NULL) {
-			ret = -ENOMEM;
-			goto out;
-		}
-		ret = crypto_shash_tfm_digest(tfm, principal, strlen(principal),
-					      cksum.data);
-		if (ret) {
-			kfree(cksum.data);
-			goto out;
-		}
-		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = cksum.len;
-		memcpy(cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data,
-		       cksum.data, cksum.len);
-		kfree(cksum.data);
+		sha256(principal, strlen(principal),
+		       cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data);
+		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = SHA256_DIGEST_SIZE;
 	} else
 		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = 0;
 
 	ret = cld_pipe_upcall(cn->cn_pipe, cmsg, nn);
 	if (!ret) {
 		ret = cmsg->cm_status;
 		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 	}
 
-out:
 	free_cld_upcall(cup);
 out_err:
 	if (ret)
 		pr_err("NFSD: Unable to create client record on stable storage: %d\n",
 				ret);

@@ -1347,13 +1329,10 @@ static int
 nfsd4_cld_check_v2(struct nfs4_client *clp)
 {
 	struct nfs4_client_reclaim *crp;
 	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 	struct cld_net *cn = nn->cld_net;
-	int status;
-	struct crypto_shash *tfm = cn->cn_tfm;
-	struct xdr_netobj cksum;
 	char *principal = NULL;
 
 	/* did we already find that this client is stable? */
 	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 		return 0;

@@ -1365,10 +1344,11 @@ nfsd4_cld_check_v2(struct nfs4_client *clp)
 
 #ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 	if (cn->cn_has_legacy) {
 		struct xdr_netobj name;
 		char dname[HEXDIR_LEN];
+		int status;
 
 		status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 		if (status)
 			return -ENOENT;
 

@@ -1387,32 +1367,22 @@ nfsd4_cld_check_v2(struct nfs4_client *clp)
 	}
 #endif
 	return -ENOENT;
 found:
 	if (crp->cr_princhash.len) {
+		u8 digest[SHA256_DIGEST_SIZE];
+
 		if (clp->cl_cred.cr_raw_principal)
 			principal = clp->cl_cred.cr_raw_principal;
 		else if (clp->cl_cred.cr_principal)
 			principal = clp->cl_cred.cr_principal;
 		if (principal == NULL)
 			return -ENOENT;
-		cksum.len = crypto_shash_digestsize(tfm);
-		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
-		if (cksum.data == NULL)
-			return -ENOENT;
-		status = crypto_shash_tfm_digest(tfm, principal,
-						 strlen(principal), cksum.data);
-		if (status) {
-			kfree(cksum.data);
+		sha256(principal, strlen(principal), digest);
+		if (memcmp(crp->cr_princhash.data, digest,
+				crp->cr_princhash.len))
 			return -ENOENT;
-		}
-		if (memcmp(crp->cr_princhash.data, cksum.data,
-				crp->cr_princhash.len)) {
-			kfree(cksum.data);
-			return -ENOENT;
-		}
-		kfree(cksum.data);
 	}
 	crp->cr_clp = clp;
 	return 0;
 }
 

@@ -1588,11 +1558,10 @@ nfsd4_cld_tracking_init(struct net *net)
 {
 	int status;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 	bool running;
 	int retries = 10;
-	struct crypto_shash *tfm;
 
 	status = nfs4_cld_state_init(net);
 	if (status)
 		return status;
 

@@ -1613,16 +1582,10 @@ nfsd4_cld_tracking_init(struct net *net)
 
 	if (!running) {
 		status = -ETIMEDOUT;
 		goto err_remove;
 	}
-	tfm = crypto_alloc_shash("sha256", 0, 0);
-	if (IS_ERR(tfm)) {
-		status = PTR_ERR(tfm);
-		goto err_remove;
-	}
-	nn->cld_net->cn_tfm = tfm;
 

Quoted 6 lines

fs/nfsd/nfs4recover.c +0 -0

 	status = nfsd4_cld_get_version(nn);
 	if (status == -EOPNOTSUPP)
 		pr_warn("NFSD: nfsdcld GetVersion upcall failed. Please upgrade nfsdcld.\n");
 

base-commit: 33035b665157558254b3c21c3f049fd728e72368

Make sense to me. Scott, can I get an R-b: from you?

Signature · 2 lines

-- 
Chuck Lever

This user of SHA-256 does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use.