1 files changed, 252 insertions, 202 deletions

diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index 4fefb219bfdc..e5b177c8e842 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -8,18 +8,17 @@
  */
 
 #define pr_fmt(fmt) "PKEY: "fmt
-#include <linux/module.h>
-#include <linux/export.h>
+#include <crypto/akcipher.h>
+#include <crypto/public_key.h>
+#include <crypto/sig.h>
+#include <keys/asymmetric-subtype.h>
+#include <linux/asn1.h>
+#include <linux/err.h>
 #include <linux/kernel.h>
-#include <linux/slab.h>
+#include <linux/module.h>
 #include <linux/seq_file.h>
-#include <linux/scatterlist.h>
-#include <linux/asn1.h>
-#include <keys/asymmetric-subtype.h>
-#include <crypto/public_key.h>
-#include <crypto/akcipher.h>
-#include <crypto/sm2.h>
-#include <crypto/sm3_base.h>
+#include <linux/slab.h>
+#include <linux/string.h>
 
 MODULE_DESCRIPTION("In-software asymmetric public-key subtype");
 MODULE_AUTHOR("Red Hat, Inc.");
@@ -43,7 +42,7 @@ static void public_key_describe(const struct key *asymmetric_key,
 void public_key_free(struct public_key *key)
 {
 	if (key) {
-		kfree(key->key);
+		kfree_sensitive(key->key);
 		kfree(key->params);
 		kfree(key);
 	}
@@ -60,39 +59,96 @@ static void public_key_destroy(void *payload0, void *payload3)
 }
 
 /*
- * Determine the crypto algorithm name.
+ * Given a public_key, and an encoding and hash_algo to be used for signing
+ * and/or verification with that key, determine the name of the corresponding
+ * akcipher algorithm.  Also check that encoding and hash_algo are allowed.
  */
-static
-int software_key_determine_akcipher(const char *encoding,
-				    const char *hash_algo,
-				    const struct public_key *pkey,
-				    char alg_name[CRYPTO_MAX_ALG_NAME])
+static int
+software_key_determine_akcipher(const struct public_key *pkey,
+				const char *encoding, const char *hash_algo,
+				char alg_name[CRYPTO_MAX_ALG_NAME], bool *sig,
+				enum kernel_pkey_operation op)
 {
 	int n;
 
-	if (strcmp(encoding, "pkcs1") == 0) {
-		/* The data wangled by the RSA algorithm is typically padded
-		 * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
-		 * sec 8.2].
+	*sig = true;
+
+	if (!encoding)
+		return -EINVAL;
+
+	if (strcmp(pkey->pkey_algo, "rsa") == 0) {
+		/*
+		 * RSA signatures usually use EMSA-PKCS1-1_5 [RFC3447 sec 8.2].
+		 */
+		if (strcmp(encoding, "pkcs1") == 0) {
+			*sig = op == kernel_pkey_sign ||
+			       op == kernel_pkey_verify;
+			if (!*sig) {
+				/*
+				 * For encrypt/decrypt, hash_algo is not used
+				 * but allowed to be set for historic reasons.
+				 */
+				n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
+					     "pkcs1pad(%s)",
+					     pkey->pkey_algo);
+			} else {
+				if (!hash_algo)
+					hash_algo = "none";
+				n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
+					     "pkcs1(%s,%s)",
+					     pkey->pkey_algo, hash_algo);
+			}
+			return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
+		}
+		if (strcmp(encoding, "raw") != 0)
+			return -EINVAL;
+		/*
+		 * Raw RSA cannot differentiate between different hash
+		 * algorithms.
+		 */
+		if (hash_algo)
+			return -EINVAL;
+		*sig = false;
+	} else if (strncmp(pkey->pkey_algo, "ecdsa", 5) == 0) {
+		if (strcmp(encoding, "x962") != 0 &&
+		    strcmp(encoding, "p1363") != 0)
+			return -EINVAL;
+		/*
+		 * ECDSA signatures are taken over a raw hash, so they don't
+		 * differentiate between different hash algorithms.  That means
+		 * that the verifier should hard-code a specific hash algorithm.
+		 * Unfortunately, in practice ECDSA is used with multiple SHAs,
+		 * so we have to allow all of them and not just one.
 		 */
 		if (!hash_algo)
-			n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
-				     "pkcs1pad(%s)",
-				     pkey->pkey_algo);
-		else
-			n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
-				     "pkcs1pad(%s,%s)",
-				     pkey->pkey_algo, hash_algo);
+			return -EINVAL;
+		if (strcmp(hash_algo, "sha1") != 0 &&
+		    strcmp(hash_algo, "sha224") != 0 &&
+		    strcmp(hash_algo, "sha256") != 0 &&
+		    strcmp(hash_algo, "sha384") != 0 &&
+		    strcmp(hash_algo, "sha512") != 0 &&
+		    strcmp(hash_algo, "sha3-256") != 0 &&
+		    strcmp(hash_algo, "sha3-384") != 0 &&
+		    strcmp(hash_algo, "sha3-512") != 0)
+			return -EINVAL;
+		n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+			     encoding, pkey->pkey_algo);
 		return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
+	} else if (strcmp(pkey->pkey_algo, "ecrdsa") == 0) {
+		if (strcmp(encoding, "raw") != 0)
+			return -EINVAL;
+		if (!hash_algo)
+			return -EINVAL;
+		if (strcmp(hash_algo, "streebog256") != 0 &&
+		    strcmp(hash_algo, "streebog512") != 0)
+			return -EINVAL;
+	} else {
+		/* Unknown public key algorithm */
+		return -ENOPKG;
 	}
-
-	if (strcmp(encoding, "raw") == 0 ||
-	    strcmp(encoding, "x962") == 0) {
-		strcpy(alg_name, pkey->pkey_algo);
-		return 0;
-	}
-
-	return -ENOPKG;
+	if (strscpy(alg_name, pkey->pkey_algo, CRYPTO_MAX_ALG_NAME) < 0)
+		return -EINVAL;
+	return 0;
 }
 
 static u8 *pkey_pack_u32(u8 *dst, u32 val)
@@ -107,57 +163,100 @@ static u8 *pkey_pack_u32(u8 *dst, u32 val)
 static int software_key_query(const struct kernel_pkey_params *params,
 			      struct kernel_pkey_query *info)
 {
-	struct crypto_akcipher *tfm;
 	struct public_key *pkey = params->key->payload.data[asym_crypto];
 	char alg_name[CRYPTO_MAX_ALG_NAME];
 	u8 *key, *ptr;
 	int ret, len;
+	bool issig;
 
-	ret = software_key_determine_akcipher(params->encoding,
-					      params->hash_algo,
-					      pkey, alg_name);
+	ret = software_key_determine_akcipher(pkey, params->encoding,
+					      params->hash_algo, alg_name,
+					      &issig, kernel_pkey_sign);
 	if (ret < 0)
 		return ret;
 
-	tfm = crypto_alloc_akcipher(alg_name, 0, 0);
-	if (IS_ERR(tfm))
-		return PTR_ERR(tfm);
-
-	ret = -ENOMEM;
 	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
 		      GFP_KERNEL);
 	if (!key)
-		goto error_free_tfm;
+		return -ENOMEM;
+
 	memcpy(key, pkey->key, pkey->keylen);
 	ptr = key + pkey->keylen;
 	ptr = pkey_pack_u32(ptr, pkey->algo);
 	ptr = pkey_pack_u32(ptr, pkey->paramlen);
 	memcpy(ptr, pkey->params, pkey->paramlen);
 
-	if (pkey->key_is_private)
-		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
-	else
-		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
-	if (ret < 0)
-		goto error_free_key;
+	memset(info, 0, sizeof(*info));
 
-	len = crypto_akcipher_maxsize(tfm);
-	info->key_size = len * 8;
-	info->max_data_size = len;
-	info->max_sig_size = len;
-	info->max_enc_size = len;
-	info->max_dec_size = len;
-	info->supported_ops = (KEYCTL_SUPPORTS_ENCRYPT |
-			       KEYCTL_SUPPORTS_VERIFY);
-	if (pkey->key_is_private)
-		info->supported_ops |= (KEYCTL_SUPPORTS_DECRYPT |
-					KEYCTL_SUPPORTS_SIGN);
-	ret = 0;
+	if (issig) {
+		struct crypto_sig *sig;
+
+		sig = crypto_alloc_sig(alg_name, 0, 0);
+		if (IS_ERR(sig)) {
+			ret = PTR_ERR(sig);
+			goto error_free_key;
+		}
+
+		if (pkey->key_is_private)
+			ret = crypto_sig_set_privkey(sig, key, pkey->keylen);
+		else
+			ret = crypto_sig_set_pubkey(sig, key, pkey->keylen);
+		if (ret < 0)
+			goto error_free_sig;
+
+		len = crypto_sig_keysize(sig);
+		info->key_size = len;
+		info->max_sig_size = crypto_sig_maxsize(sig);
+		info->max_data_size = crypto_sig_digestsize(sig);
+
+		info->supported_ops = KEYCTL_SUPPORTS_VERIFY;
+		if (pkey->key_is_private)
+			info->supported_ops |= KEYCTL_SUPPORTS_SIGN;
+
+		if (strcmp(params->encoding, "pkcs1") == 0) {
+			info->max_enc_size = len / BITS_PER_BYTE;
+			info->max_dec_size = len / BITS_PER_BYTE;
+
+			info->supported_ops |= KEYCTL_SUPPORTS_ENCRYPT;
+			if (pkey->key_is_private)
+				info->supported_ops |= KEYCTL_SUPPORTS_DECRYPT;
+		}
+
+error_free_sig:
+		crypto_free_sig(sig);
+	} else {
+		struct crypto_akcipher *tfm;
+
+		tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+		if (IS_ERR(tfm)) {
+			ret = PTR_ERR(tfm);
+			goto error_free_key;
+		}
+
+		if (pkey->key_is_private)
+			ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
+		else
+			ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
+		if (ret < 0)
+			goto error_free_akcipher;
+
+		len = crypto_akcipher_maxsize(tfm);
+		info->key_size = len * BITS_PER_BYTE;
+		info->max_sig_size = len;
+		info->max_data_size = len;
+		info->max_enc_size = len;
+		info->max_dec_size = len;
+
+		info->supported_ops = KEYCTL_SUPPORTS_ENCRYPT;
+		if (pkey->key_is_private)
+			info->supported_ops |= KEYCTL_SUPPORTS_DECRYPT;
+
+error_free_akcipher:
+		crypto_free_akcipher(tfm);
+	}
 
 error_free_key:
-	kfree(key);
-error_free_tfm:
-	crypto_free_akcipher(tfm);
+	kfree_sensitive(key);
 	pr_devel("<==%s() = %d\n", __func__, ret);
 	return ret;
 }
@@ -169,35 +268,25 @@ static int software_key_eds_op(struct kernel_pkey_params *params,
 			       const void *in, void *out)
 {
 	const struct public_key *pkey = params->key->payload.data[asym_crypto];
-	struct akcipher_request *req;
-	struct crypto_akcipher *tfm;
-	struct crypto_wait cwait;
-	struct scatterlist in_sg, out_sg;
 	char alg_name[CRYPTO_MAX_ALG_NAME];
+	struct crypto_akcipher *tfm;
+	struct crypto_sig *sig;
 	char *key, *ptr;
+	bool issig;
 	int ret;
 
 	pr_devel("==>%s()\n", __func__);
 
-	ret = software_key_determine_akcipher(params->encoding,
-					      params->hash_algo,
-					      pkey, alg_name);
+	ret = software_key_determine_akcipher(pkey, params->encoding,
+					      params->hash_algo, alg_name,
+					      &issig, params->op);
 	if (ret < 0)
 		return ret;
 
-	tfm = crypto_alloc_akcipher(alg_name, 0, 0);
-	if (IS_ERR(tfm))
-		return PTR_ERR(tfm);
-
-	ret = -ENOMEM;
-	req = akcipher_request_alloc(tfm, GFP_KERNEL);
-	if (!req)
-		goto error_free_tfm;
-
 	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
 		      GFP_KERNEL);
 	if (!key)
-		goto error_free_req;
+		return -ENOMEM;
 
 	memcpy(key, pkey->key, pkey->keylen);
 	ptr = key + pkey->keylen;
@@ -205,118 +294,84 @@ static int software_key_eds_op(struct kernel_pkey_params *params,
 	ptr = pkey_pack_u32(ptr, pkey->paramlen);
 	memcpy(ptr, pkey->params, pkey->paramlen);
 
-	if (pkey->key_is_private)
-		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
-	else
-		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
-	if (ret)
-		goto error_free_key;
+	if (issig) {
+		sig = crypto_alloc_sig(alg_name, 0, 0);
+		if (IS_ERR(sig)) {
+			ret = PTR_ERR(sig);
+			goto error_free_key;
+		}
 
-	sg_init_one(&in_sg, in, params->in_len);
-	sg_init_one(&out_sg, out, params->out_len);
-	akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
-				   params->out_len);
-	crypto_init_wait(&cwait);
-	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
-				      CRYPTO_TFM_REQ_MAY_SLEEP,
-				      crypto_req_done, &cwait);
+		if (pkey->key_is_private)
+			ret = crypto_sig_set_privkey(sig, key, pkey->keylen);
+		else
+			ret = crypto_sig_set_pubkey(sig, key, pkey->keylen);
+		if (ret)
+			goto error_free_tfm;
+	} else {
+		tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+		if (IS_ERR(tfm)) {
+			ret = PTR_ERR(tfm);
+			goto error_free_key;
+		}
+
+		if (pkey->key_is_private)
+			ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
+		else
+			ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
+		if (ret)
+			goto error_free_tfm;
+	}
+
+	ret = -EINVAL;
 
 	/* Perform the encryption calculation. */
 	switch (params->op) {
 	case kernel_pkey_encrypt:
-		ret = crypto_akcipher_encrypt(req);
+		if (issig)
+			break;
+		ret = crypto_akcipher_sync_encrypt(tfm, in, params->in_len,
+						   out, params->out_len);
 		break;
 	case kernel_pkey_decrypt:
-		ret = crypto_akcipher_decrypt(req);
+		if (issig)
+			break;
+		ret = crypto_akcipher_sync_decrypt(tfm, in, params->in_len,
+						   out, params->out_len);
 		break;
 	case kernel_pkey_sign:
-		ret = crypto_akcipher_sign(req);
+		if (!issig)
+			break;
+		ret = crypto_sig_sign(sig, in, params->in_len,
+				      out, params->out_len);
 		break;
 	default:
 		BUG();
 	}
 
-	ret = crypto_wait_req(ret, &cwait);
-	if (ret == 0)
-		ret = req->dst_len;
+	if (!issig && ret == 0)
+		ret = crypto_akcipher_maxsize(tfm);
 
-error_free_key:
-	kfree(key);
-error_free_req:
-	akcipher_request_free(req);
 error_free_tfm:
-	crypto_free_akcipher(tfm);
+	if (issig)
+		crypto_free_sig(sig);
+	else
+		crypto_free_akcipher(tfm);
+error_free_key:
+	kfree_sensitive(key);
 	pr_devel("<==%s() = %d\n", __func__, ret);
 	return ret;
 }
 
-#if IS_REACHABLE(CONFIG_CRYPTO_SM2)
-static int cert_sig_digest_update(const struct public_key_signature *sig,
-				  struct crypto_akcipher *tfm_pkey)
-{
-	struct crypto_shash *tfm;
-	struct shash_desc *desc;
-	size_t desc_size;
-	unsigned char dgst[SM3_DIGEST_SIZE];
-	int ret;
-
-	BUG_ON(!sig->data);
-
-	ret = sm2_compute_z_digest(tfm_pkey, SM2_DEFAULT_USERID,
-					SM2_DEFAULT_USERID_LEN, dgst);
-	if (ret)
-		return ret;
-
-	tfm = crypto_alloc_shash(sig->hash_algo, 0, 0);
-	if (IS_ERR(tfm))
-		return PTR_ERR(tfm);
-
-	desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
-	desc = kzalloc(desc_size, GFP_KERNEL);
-	if (!desc) {
-		ret = -ENOMEM;
-		goto error_free_tfm;
-	}
-
-	desc->tfm = tfm;
-
-	ret = crypto_shash_init(desc);
-	if (ret < 0)
-		goto error_free_desc;
-
-	ret = crypto_shash_update(desc, dgst, SM3_DIGEST_SIZE);
-	if (ret < 0)
-		goto error_free_desc;
-
-	ret = crypto_shash_finup(desc, sig->data, sig->data_size, sig->digest);
-
-error_free_desc:
-	kfree(desc);
-error_free_tfm:
-	crypto_free_shash(tfm);
-	return ret;
-}
-#else
-static inline int cert_sig_digest_update(
-	const struct public_key_signature *sig,
-	struct crypto_akcipher *tfm_pkey)
-{
-	return -ENOTSUPP;
-}
-#endif /* ! IS_REACHABLE(CONFIG_CRYPTO_SM2) */
-
 /*
  * Verify a signature using a public key.
  */
 int public_key_verify_signature(const struct public_key *pkey,
 				const struct public_key_signature *sig)
 {
-	struct crypto_wait cwait;
-	struct crypto_akcipher *tfm;
-	struct akcipher_request *req;
-	struct scatterlist src_sg[2];
 	char alg_name[CRYPTO_MAX_ALG_NAME];
+	struct crypto_sig *tfm;
 	char *key, *ptr;
+	bool issig;
 	int ret;
 
 	pr_devel("==>%s()\n", __func__);
@@ -325,25 +380,37 @@ int public_key_verify_signature(const struct public_key *pkey,
 	BUG_ON(!sig);
 	BUG_ON(!sig->s);
 
-	ret = software_key_determine_akcipher(sig->encoding,
-					      sig->hash_algo,
-					      pkey, alg_name);
+	/*
+	 * If the signature specifies a public key algorithm, it *must* match
+	 * the key's actual public key algorithm.
+	 *
+	 * Small exception: ECDSA signatures don't specify the curve, but ECDSA
+	 * keys do.  So the strings can mismatch slightly in that case:
+	 * "ecdsa-nist-*" for the key, but "ecdsa" for the signature.
+	 */
+	if (sig->pkey_algo) {
+		if (strcmp(pkey->pkey_algo, sig->pkey_algo) != 0 &&
+		    (strncmp(pkey->pkey_algo, "ecdsa-", 6) != 0 ||
+		     strcmp(sig->pkey_algo, "ecdsa") != 0))
+			return -EKEYREJECTED;
+	}
+
+	ret = software_key_determine_akcipher(pkey, sig->encoding,
+					      sig->hash_algo, alg_name,
+					      &issig, kernel_pkey_verify);
 	if (ret < 0)
 		return ret;
 
-	tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+	tfm = crypto_alloc_sig(alg_name, 0, 0);
 	if (IS_ERR(tfm))
 		return PTR_ERR(tfm);
 
-	ret = -ENOMEM;
-	req = akcipher_request_alloc(tfm, GFP_KERNEL);
-	if (!req)
-		goto error_free_tfm;
-
 	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
 		      GFP_KERNEL);
-	if (!key)
-		goto error_free_req;
+	if (!key) {
+		ret = -ENOMEM;
+		goto error_free_tfm;
+	}
 
 	memcpy(key, pkey->key, pkey->keylen);
 	ptr = key + pkey->keylen;
@@ -352,36 +419,19 @@ int public_key_verify_signature(const struct public_key *pkey,
 	memcpy(ptr, pkey->params, pkey->paramlen);
 
 	if (pkey->key_is_private)
-		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
+		ret = crypto_sig_set_privkey(tfm, key, pkey->keylen);
 	else
-		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
+		ret = crypto_sig_set_pubkey(tfm, key, pkey->keylen);
 	if (ret)
 		goto error_free_key;
 
-	if (sig->pkey_algo && strcmp(sig->pkey_algo, "sm2") == 0 &&
-	    sig->data_size) {
-		ret = cert_sig_digest_update(sig, tfm);
-		if (ret)
-			goto error_free_key;
-	}
-
-	sg_init_table(src_sg, 2);
-	sg_set_buf(&src_sg[0], sig->s, sig->s_size);
-	sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
-	akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
-				   sig->digest_size);
-	crypto_init_wait(&cwait);
-	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
-				      CRYPTO_TFM_REQ_MAY_SLEEP,
-				      crypto_req_done, &cwait);
-	ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
+	ret = crypto_sig_verify(tfm, sig->s, sig->s_size,
+				sig->digest, sig->digest_size);
 
 error_free_key:
-	kfree(key);
-error_free_req:
-	akcipher_request_free(req);
+	kfree_sensitive(key);
 error_free_tfm:
-	crypto_free_akcipher(tfm);
+	crypto_free_sig(tfm);
 	pr_devel("<==%s() = %d\n", __func__, ret);
 	if (WARN_ON_ONCE(ret > 0))
 		ret = -EINVAL;