crypto: hash - annotate algorithms taking optional key

commit a208fa8f33031b9e0aba44c7d1b7e68eb0cbd29e upstream.

We need to consistently enforce that keyed hashes cannot be used without
setting the key.  To do this we need a reliable way to determine whether
a given hash algorithm is keyed or not.  AF_ALG currently does this by
checking for the presence of a ->setkey() method.  However, this is
actually slightly broken because the CRC-32 algorithms implement
->setkey() but can also be used without a key.  (The CRC-32 "key" is not
actually a cryptographic key but rather represents the initial state.
If not overridden, then a default initial state is used.)

Prepare to fix this by introducing a flag CRYPTO_ALG_OPTIONAL_KEY which
indicates that the algorithm has a ->setkey() method, but it is not
required to be called.  Then set it on all the CRC-32 algorithms.

The same also applies to the Adler-32 implementation in Lustre.

Also, the cryptd and mcryptd templates have to pass through the flag
from their underlying algorithm.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


diff --git a/arch/arm64/crypto/crc32-arm64.c b/arch/arm64/crypto/crc32-arm64.c
index 6a37c3c..3ec568a 100644
--- a/arch/arm64/crypto/crc32-arm64.c
+++ b/arch/arm64/crypto/crc32-arm64.c
@@ -232,6 +232,7 @@
 		.cra_name		=	"crc32",
 		.cra_driver_name	=	"crc32-arm64-hw",
 		.cra_priority		=	300,
+		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_alignmask		=	0,
 		.cra_ctxsize		=	sizeof(struct chksum_ctx),
@@ -253,6 +254,7 @@
 		.cra_name		=	"crc32c",
 		.cra_driver_name	=	"crc32c-arm64-hw",
 		.cra_priority		=	300,
+		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_alignmask		=	0,
 		.cra_ctxsize		=	sizeof(struct chksum_ctx),
diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
index f058e0c..fd1d6c8 100644
--- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c
+++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
@@ -141,6 +141,7 @@
 		.cra_name		= "crc32c",
 		.cra_driver_name	= "crc32c-vpmsum",
 		.cra_priority		= 200,
+		.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(u32),
 		.cra_module		= THIS_MODULE,
diff --git a/arch/s390/crypto/crc32-vx.c b/arch/s390/crypto/crc32-vx.c
index 992e630..6f4985f 100644
--- a/arch/s390/crypto/crc32-vx.c
+++ b/arch/s390/crypto/crc32-vx.c
@@ -238,6 +238,7 @@
 			.cra_name	 = "crc32",
 			.cra_driver_name = "crc32-vx",
 			.cra_priority	 = 200,
+			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
 			.cra_ctxsize	 = sizeof(struct crc_ctx),
 			.cra_module	 = THIS_MODULE,
@@ -258,6 +259,7 @@
 			.cra_name	 = "crc32be",
 			.cra_driver_name = "crc32be-vx",
 			.cra_priority	 = 200,
+			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
 			.cra_ctxsize	 = sizeof(struct crc_ctx),
 			.cra_module	 = THIS_MODULE,
@@ -278,6 +280,7 @@
 			.cra_name	 = "crc32c",
 			.cra_driver_name = "crc32c-vx",
 			.cra_priority	 = 200,
+			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
 			.cra_ctxsize	 = sizeof(struct crc_ctx),
 			.cra_module	 = THIS_MODULE,
diff --git a/arch/sparc/crypto/crc32c_glue.c b/arch/sparc/crypto/crc32c_glue.c
index d1064e4..8aa6646 100644
--- a/arch/sparc/crypto/crc32c_glue.c
+++ b/arch/sparc/crypto/crc32c_glue.c
@@ -133,6 +133,7 @@
 		.cra_name		=	"crc32c",
 		.cra_driver_name	=	"crc32c-sparc64",
 		.cra_priority		=	SPARC_CR_OPCODE_PRIORITY,
+		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		=	sizeof(u32),
 		.cra_alignmask		=	7,
diff --git a/arch/x86/crypto/crc32-pclmul_glue.c b/arch/x86/crypto/crc32-pclmul_glue.c
index 27226df..c8d9cda 100644
--- a/arch/x86/crypto/crc32-pclmul_glue.c
+++ b/arch/x86/crypto/crc32-pclmul_glue.c
@@ -162,6 +162,7 @@
 			.cra_name		= "crc32",
 			.cra_driver_name	= "crc32-pclmul",
 			.cra_priority		= 200,
+			.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 			.cra_blocksize		= CHKSUM_BLOCK_SIZE,
 			.cra_ctxsize		= sizeof(u32),
 			.cra_module		= THIS_MODULE,
diff --git a/arch/x86/crypto/crc32c-intel_glue.c b/arch/x86/crypto/crc32c-intel_glue.c
index 0857b1a..60a391b 100644
--- a/arch/x86/crypto/crc32c-intel_glue.c
+++ b/arch/x86/crypto/crc32c-intel_glue.c
@@ -239,6 +239,7 @@
 		.cra_name		=	"crc32c",
 		.cra_driver_name	=	"crc32c-intel",
 		.cra_priority		=	200,
+		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		=	sizeof(u32),
 		.cra_module		=	THIS_MODULE,
diff --git a/crypto/crc32_generic.c b/crypto/crc32_generic.c
index aa2a25f..718cbce 100644
--- a/crypto/crc32_generic.c
+++ b/crypto/crc32_generic.c
@@ -133,6 +133,7 @@
 		.cra_name		= "crc32",
 		.cra_driver_name	= "crc32-generic",
 		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(u32),
 		.cra_module		= THIS_MODULE,
diff --git a/crypto/crc32c_generic.c b/crypto/crc32c_generic.c
index 4c0a0e2..3723203 100644
--- a/crypto/crc32c_generic.c
+++ b/crypto/crc32c_generic.c
@@ -146,6 +146,7 @@
 		.cra_name		=	"crc32c",
 		.cra_driver_name	=	"crc32c-generic",
 		.cra_priority		=	100,
+		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_alignmask		=	3,
 		.cra_ctxsize		=	sizeof(struct chksum_ctx),
diff --git a/crypto/cryptd.c b/crypto/cryptd.c
index af9ad45..9b66ce7 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -673,10 +673,9 @@
 	if (err)
 		goto out_free_inst;
 
-	type = CRYPTO_ALG_ASYNC;
-	if (alg->cra_flags & CRYPTO_ALG_INTERNAL)
-		type |= CRYPTO_ALG_INTERNAL;
-	inst->alg.halg.base.cra_flags = type;
+	inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC |
+		(alg->cra_flags & (CRYPTO_ALG_INTERNAL |
+				   CRYPTO_ALG_OPTIONAL_KEY));
 
 	inst->alg.halg.digestsize = salg->digestsize;
 	inst->alg.halg.statesize = salg->statesize;
diff --git a/crypto/mcryptd.c b/crypto/mcryptd.c
index 6e9389c..7406ed0 100644
--- a/crypto/mcryptd.c
+++ b/crypto/mcryptd.c
@@ -516,10 +516,9 @@
 	if (err)
 		goto out_free_inst;
 
-	type = CRYPTO_ALG_ASYNC;
-	if (alg->cra_flags & CRYPTO_ALG_INTERNAL)
-		type |= CRYPTO_ALG_INTERNAL;
-	inst->alg.halg.base.cra_flags = type;
+	inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC |
+		(alg->cra_flags & (CRYPTO_ALG_INTERNAL |
+				   CRYPTO_ALG_OPTIONAL_KEY));
 
 	inst->alg.halg.digestsize = halg->digestsize;
 	inst->alg.halg.statesize = halg->statesize;
diff --git a/drivers/crypto/bfin_crc.c b/drivers/crypto/bfin_crc.c
index 10db7df..2ee1180 100644
--- a/drivers/crypto/bfin_crc.c
+++ b/drivers/crypto/bfin_crc.c
@@ -494,7 +494,8 @@
 		.cra_driver_name	= DRIVER_NAME,
 		.cra_priority		= 100,
 		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
-						CRYPTO_ALG_ASYNC,
+						CRYPTO_ALG_ASYNC |
+						CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(struct bfin_crypto_crc_ctx),
 		.cra_alignmask		= 3,
diff --git a/drivers/staging/lustre/lnet/libcfs/linux/linux-crypto-adler.c b/drivers/staging/lustre/lnet/libcfs/linux/linux-crypto-adler.c
index db05727..ab30a0f 100644
--- a/drivers/staging/lustre/lnet/libcfs/linux/linux-crypto-adler.c
+++ b/drivers/staging/lustre/lnet/libcfs/linux/linux-crypto-adler.c
@@ -119,6 +119,7 @@
 		.cra_name		= "adler32",
 		.cra_driver_name	= "adler32-zlib",
 		.cra_priority		= 100,
+		.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
 		.cra_ctxsize		= sizeof(u32),
 		.cra_module		= THIS_MODULE,
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 7cee555..b0175fa 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -103,6 +103,12 @@
 #define CRYPTO_ALG_INTERNAL		0x00002000
 
 /*
+ * Set if the algorithm has a ->setkey() method but can be used without
+ * calling it first, i.e. there is a default key.
+ */
+#define CRYPTO_ALG_OPTIONAL_KEY		0x00004000
+
+/*
  * Transform masks and values (for crt_flags).
  */
 #define CRYPTO_TFM_REQ_MASK		0x000fff00