[PATCH v1 02/41] SUNRPC: Remove .blocksize field from struct gss_krb5_enctype
From: Chuck Lever <cel@kernel.org>
Date: 2023-01-13 15:28:38
Subsystem:
kernel nfsd, sunrpc, and lockd servers, networking [general], nfs, sunrpc, and lockd clients, the rest · Maintainers:
Chuck Lever, Jeff Layton, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Trond Myklebust, Anna Schumaker, Linus Torvalds
From: Chuck Lever <redacted> It is not clear from documenting comments, specifications, or code usage what value the gss_krb5_enctype.blocksize field is supposed to store. The "encryption blocksize" depends only on the cipher being used, so that value can be derived where it's needed instead of stored as a constant. RFC 3961 Section 5.2 says:
cipher block size, c This is the block size of the block cipher underlying the encryption and decryption functions indicated above, used for key derivation and for the size of the message confounder and initial vector. (If a block cipher is not in use, some comparable parameter should be determined.) It must be at least 5 octets. This is not actually an independent parameter; rather, it is a property of the functions E and D. It is listed here to clarify the distinction between it and the message block size, m.
In the Linux kernel's implemenation of the SunRPC RPCSEC GSS Kerberos 5 mechanism, the cipher block size, which is dependent on the encryption and decryption transforms, is used only in krb5_derive_key(), so it is straightforward to replace it. Tested-by: Scott Mayhew <redacted> Signed-off-by: Chuck Lever <redacted> --- include/linux/sunrpc/gss_krb5.h | 1 - net/sunrpc/auth_gss/gss_krb5_keys.c | 4 +--- net/sunrpc/auth_gss/gss_krb5_mech.c | 4 ---- 3 files changed, 1 insertion(+), 8 deletions(-)
diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
index 0135139ddf20..9a833825b55b 100644
--- a/include/linux/sunrpc/gss_krb5.h
+++ b/include/linux/sunrpc/gss_krb5.h@@ -64,7 +64,6 @@ struct gss_krb5_enctype { const char *cksum_name; /* crypto checksum name */ const u16 signalg; /* signing algorithm */ const u16 sealalg; /* sealing algorithm */ - const u32 blocksize; /* encryption blocksize */ const u32 conflen; /* confounder length (normally the same as the blocksize) */
diff --git a/net/sunrpc/auth_gss/gss_krb5_keys.c b/net/sunrpc/auth_gss/gss_krb5_keys.c
index 726c076950c0..554cfd23f288 100644
--- a/net/sunrpc/auth_gss/gss_krb5_keys.c
+++ b/net/sunrpc/auth_gss/gss_krb5_keys.c@@ -150,7 +150,6 @@ u32 krb5_derive_key(const struct gss_krb5_enctype *gk5e, struct crypto_sync_skcipher *cipher; u32 ret = EINVAL; - blocksize = gk5e->blocksize; keybytes = gk5e->keybytes; keylength = gk5e->keylength;
@@ -160,11 +159,10 @@ u32 krb5_derive_key(const struct gss_krb5_enctype *gk5e, cipher = crypto_alloc_sync_skcipher(gk5e->encrypt_name, 0, 0); if (IS_ERR(cipher)) goto err_return; + blocksize = crypto_sync_skcipher_blocksize(cipher); if (crypto_sync_skcipher_setkey(cipher, inkey->data, inkey->len)) goto err_return; - /* allocate and set up buffers */ - ret = ENOMEM; inblockdata = kmalloc(blocksize, gfp_mask); if (inblockdata == NULL)
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index 1c092b05c2bb..dd85fc9ca80b 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c@@ -47,7 +47,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .sealalg = SEAL_ALG_DES, .keybytes = 7, .keylength = 8, - .blocksize = 8, .conflen = 8, .cksumlength = 8, .keyed_cksum = 0,
@@ -69,7 +68,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .sealalg = SEAL_ALG_DES3KD, .keybytes = 21, .keylength = 24, - .blocksize = 8, .conflen = 8, .cksumlength = 20, .keyed_cksum = 1,
@@ -92,7 +90,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .sealalg = -1, .keybytes = 16, .keylength = 16, - .blocksize = 16, .conflen = 16, .cksumlength = 12, .keyed_cksum = 1,
@@ -115,7 +112,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .sealalg = -1, .keybytes = 32, .keylength = 32, - .blocksize = 16, .conflen = 16, .cksumlength = 12, .keyed_cksum = 1,