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 (file)
--- a/arch/arm64/crypto/crc32-arm64.c
+++ b/arch/arm64/crypto/crc32-arm64.c
@@ -232,6 +232,7 @@ static struct shash_alg crc32_alg = {
                .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 @@ static struct shash_alg crc32c_alg = {
                .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 (file)
--- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c
+++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
@@ -141,6 +141,7 @@ static struct shash_alg alg = {
                .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 (file)
--- a/arch/s390/crypto/crc32-vx.c
+++ b/arch/s390/crypto/crc32-vx.c
@@ -238,6 +238,7 @@ static struct shash_alg crc32_vx_algs[] = {
                        .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 @@ static struct shash_alg crc32_vx_algs[] = {
                        .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 @@ static struct shash_alg crc32_vx_algs[] = {
                        .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 (file)
--- a/arch/sparc/crypto/crc32c_glue.c
+++ b/arch/sparc/crypto/crc32c_glue.c
@@ -133,6 +133,7 @@ static struct shash_alg alg = {
                .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 (file)
--- a/arch/x86/crypto/crc32-pclmul_glue.c
+++ b/arch/x86/crypto/crc32-pclmul_glue.c
@@ -162,6 +162,7 @@ static struct shash_alg alg = {
                        .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 (file)
--- a/arch/x86/crypto/crc32c-intel_glue.c
+++ b/arch/x86/crypto/crc32c-intel_glue.c
@@ -239,6 +239,7 @@ static struct shash_alg alg = {
                .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 (file)
--- a/crypto/crc32_generic.c
+++ b/crypto/crc32_generic.c
@@ -133,6 +133,7 @@ static struct shash_alg alg = {
                .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 (file)
--- a/crypto/crc32c_generic.c
+++ b/crypto/crc32c_generic.c
@@ -146,6 +146,7 @@ static struct shash_alg alg = {
                .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 (file)
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -673,10 +673,9 @@ static int cryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
        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 (file)
--- a/crypto/mcryptd.c
+++ b/crypto/mcryptd.c
@@ -516,10 +516,9 @@ static int mcryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
        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 (file)
--- a/drivers/crypto/bfin_crc.c
+++ b/drivers/crypto/bfin_crc.c
@@ -494,7 +494,8 @@ static struct ahash_alg algs = {
                .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 (file)
--- 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 @@ static struct shash_alg alg = {
                .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 (file)
--- 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