1 files changed, 128 insertions, 63 deletions

diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 6d003096b5bc..b37cae914987 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -19,15 +19,13 @@
 struct x509_parse_context {
 	struct x509_certificate	*cert;		/* Certificate being constructed */
 	unsigned long	data;			/* Start of data */
-	const void	*cert_start;		/* Start of cert content */
 	const void	*key;			/* Key data */
 	size_t		key_size;		/* Size of key data */
 	const void	*params;		/* Key parameters */
 	size_t		params_size;		/* Size of key parameters */
-	enum OID	key_algo;		/* Public key algorithm */
+	enum OID	key_algo;		/* Algorithm used by the cert's key */
 	enum OID	last_oid;		/* Last OID encountered */
-	enum OID	algo_oid;		/* Algorithm OID */
-	unsigned char	nr_mpi;			/* Number of MPIs stored */
+	enum OID	sig_algo;		/* Algorithm used to sign the cert */
 	u8		o_size;			/* Size of organizationName (O) */
 	u8		cn_size;		/* Size of commonName (CN) */
 	u8		email_size;		/* Size of emailAddress */
@@ -62,24 +60,23 @@ EXPORT_SYMBOL_GPL(x509_free_certificate);
  */
 struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
 {
-	struct x509_certificate *cert;
-	struct x509_parse_context *ctx;
+	struct x509_certificate *cert __free(x509_free_certificate) = NULL;
+	struct x509_parse_context *ctx __free(kfree) = NULL;
 	struct asymmetric_key_id *kid;
 	long ret;
 
-	ret = -ENOMEM;
 	cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL);
 	if (!cert)
-		goto error_no_cert;
+		return ERR_PTR(-ENOMEM);
 	cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
 	if (!cert->pub)
-		goto error_no_ctx;
+		return ERR_PTR(-ENOMEM);
 	cert->sig = kzalloc(sizeof(struct public_key_signature), GFP_KERNEL);
 	if (!cert->sig)
-		goto error_no_ctx;
+		return ERR_PTR(-ENOMEM);
 	ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
 	if (!ctx)
-		goto error_no_ctx;
+		return ERR_PTR(-ENOMEM);
 
 	ctx->cert = cert;
 	ctx->data = (unsigned long)data;
@@ -87,7 +84,7 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
 	/* Attempt to decode the certificate */
 	ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen);
 	if (ret < 0)
-		goto error_decode;
+		return ERR_PTR(ret);
 
 	/* Decode the AuthorityKeyIdentifier */
 	if (ctx->raw_akid) {
@@ -97,20 +94,19 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
 				       ctx->raw_akid, ctx->raw_akid_size);
 		if (ret < 0) {
 			pr_warn("Couldn't decode AuthKeyIdentifier\n");
-			goto error_decode;
+			return ERR_PTR(ret);
 		}
 	}
 
-	ret = -ENOMEM;
 	cert->pub->key = kmemdup(ctx->key, ctx->key_size, GFP_KERNEL);
 	if (!cert->pub->key)
-		goto error_decode;
+		return ERR_PTR(-ENOMEM);
 
 	cert->pub->keylen = ctx->key_size;
 
 	cert->pub->params = kmemdup(ctx->params, ctx->params_size, GFP_KERNEL);
 	if (!cert->pub->params)
-		goto error_decode;
+		return ERR_PTR(-ENOMEM);
 
 	cert->pub->paramlen = ctx->params_size;
 	cert->pub->algo = ctx->key_algo;
@@ -118,33 +114,23 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
 	/* Grab the signature bits */
 	ret = x509_get_sig_params(cert);
 	if (ret < 0)
-		goto error_decode;
+		return ERR_PTR(ret);
 
 	/* Generate cert issuer + serial number key ID */
 	kid = asymmetric_key_generate_id(cert->raw_serial,
 					 cert->raw_serial_size,
 					 cert->raw_issuer,
 					 cert->raw_issuer_size);
-	if (IS_ERR(kid)) {
-		ret = PTR_ERR(kid);
-		goto error_decode;
-	}
+	if (IS_ERR(kid))
+		return ERR_CAST(kid);
 	cert->id = kid;
 
 	/* Detect self-signed certificates */
 	ret = x509_check_for_self_signed(cert);
 	if (ret < 0)
-		goto error_decode;
+		return ERR_PTR(ret);
 
-	kfree(ctx);
-	return cert;
-
-error_decode:
-	kfree(ctx);
-error_no_ctx:
-	x509_free_certificate(cert);
-error_no_cert:
-	return ERR_PTR(ret);
+	return_ptr(cert);
 }
 EXPORT_SYMBOL_GPL(x509_cert_parse);
 
@@ -187,26 +173,19 @@ int x509_note_tbs_certificate(void *context, size_t hdrlen,
 }
 
 /*
- * Record the public key algorithm
+ * Record the algorithm that was used to sign this certificate.
  */
-int x509_note_pkey_algo(void *context, size_t hdrlen,
-			unsigned char tag,
-			const void *value, size_t vlen)
+int x509_note_sig_algo(void *context, size_t hdrlen, unsigned char tag,
+		       const void *value, size_t vlen)
 {
 	struct x509_parse_context *ctx = context;
 
 	pr_debug("PubKey Algo: %u\n", ctx->last_oid);
 
 	switch (ctx->last_oid) {
-	case OID_md2WithRSAEncryption:
-	case OID_md3WithRSAEncryption:
 	default:
 		return -ENOPKG; /* Unsupported combination */
 
-	case OID_md4WithRSAEncryption:
-		ctx->cert->sig->hash_algo = "md4";
-		goto rsa_pkcs1;
-
 	case OID_sha1WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha1";
 		goto rsa_pkcs1;
@@ -231,6 +210,18 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
 		ctx->cert->sig->hash_algo = "sha1";
 		goto ecdsa;
 
+	case OID_id_rsassa_pkcs1_v1_5_with_sha3_256:
+		ctx->cert->sig->hash_algo = "sha3-256";
+		goto rsa_pkcs1;
+
+	case OID_id_rsassa_pkcs1_v1_5_with_sha3_384:
+		ctx->cert->sig->hash_algo = "sha3-384";
+		goto rsa_pkcs1;
+
+	case OID_id_rsassa_pkcs1_v1_5_with_sha3_512:
+		ctx->cert->sig->hash_algo = "sha3-512";
+		goto rsa_pkcs1;
+
 	case OID_id_ecdsa_with_sha224:
 		ctx->cert->sig->hash_algo = "sha224";
 		goto ecdsa;
@@ -247,6 +238,18 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
 		ctx->cert->sig->hash_algo = "sha512";
 		goto ecdsa;
 
+	case OID_id_ecdsa_with_sha3_256:
+		ctx->cert->sig->hash_algo = "sha3-256";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha3_384:
+		ctx->cert->sig->hash_algo = "sha3-384";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha3_512:
+		ctx->cert->sig->hash_algo = "sha3-512";
+		goto ecdsa;
+
 	case OID_gost2012Signature256:
 		ctx->cert->sig->hash_algo = "streebog256";
 		goto ecrdsa;
@@ -254,31 +257,22 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
 	case OID_gost2012Signature512:
 		ctx->cert->sig->hash_algo = "streebog512";
 		goto ecrdsa;
-
-	case OID_SM2_with_SM3:
-		ctx->cert->sig->hash_algo = "sm3";
-		goto sm2;
 	}
 
 rsa_pkcs1:
 	ctx->cert->sig->pkey_algo = "rsa";
 	ctx->cert->sig->encoding = "pkcs1";
-	ctx->algo_oid = ctx->last_oid;
+	ctx->sig_algo = ctx->last_oid;
 	return 0;
 ecrdsa:
 	ctx->cert->sig->pkey_algo = "ecrdsa";
 	ctx->cert->sig->encoding = "raw";
-	ctx->algo_oid = ctx->last_oid;
-	return 0;
-sm2:
-	ctx->cert->sig->pkey_algo = "sm2";
-	ctx->cert->sig->encoding = "raw";
-	ctx->algo_oid = ctx->last_oid;
+	ctx->sig_algo = ctx->last_oid;
 	return 0;
 ecdsa:
 	ctx->cert->sig->pkey_algo = "ecdsa";
 	ctx->cert->sig->encoding = "x962";
-	ctx->algo_oid = ctx->last_oid;
+	ctx->sig_algo = ctx->last_oid;
 	return 0;
 }
 
@@ -291,17 +285,21 @@ int x509_note_signature(void *context, size_t hdrlen,
 {
 	struct x509_parse_context *ctx = context;
 
-	pr_debug("Signature type: %u size %zu\n", ctx->last_oid, vlen);
+	pr_debug("Signature: alg=%u, size=%zu\n", ctx->last_oid, vlen);
 
-	if (ctx->last_oid != ctx->algo_oid) {
-		pr_warn("Got cert with pkey (%u) and sig (%u) algorithm OIDs\n",
-			ctx->algo_oid, ctx->last_oid);
+	/*
+	 * In X.509 certificates, the signature's algorithm is stored in two
+	 * places: inside the TBSCertificate (the data that is signed), and
+	 * alongside the signature.  These *must* match.
+	 */
+	if (ctx->last_oid != ctx->sig_algo) {
+		pr_warn("signatureAlgorithm (%u) differs from tbsCertificate.signature (%u)\n",
+			ctx->last_oid, ctx->sig_algo);
 		return -EINVAL;
 	}
 
 	if (strcmp(ctx->cert->sig->pkey_algo, "rsa") == 0 ||
 	    strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0 ||
-	    strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0 ||
 	    strcmp(ctx->cert->sig->pkey_algo, "ecdsa") == 0) {
 		/* Discard the BIT STRING metadata */
 		if (vlen < 1 || *(const u8 *)value != 0)
@@ -374,10 +372,9 @@ static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen,
 
 	/* Empty name string if no material */
 	if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) {
-		buffer = kmalloc(1, GFP_KERNEL);
+		buffer = kzalloc(1, GFP_KERNEL);
 		if (!buffer)
 			return -ENOMEM;
-		buffer[0] = 0;
 		goto done;
 	}
 
@@ -441,8 +438,18 @@ int x509_note_issuer(void *context, size_t hdrlen,
 		     const void *value, size_t vlen)
 {
 	struct x509_parse_context *ctx = context;
+	struct asymmetric_key_id *kid;
+
 	ctx->cert->raw_issuer = value;
 	ctx->cert->raw_issuer_size = vlen;
+
+	if (!ctx->cert->sig->auth_ids[2]) {
+		kid = asymmetric_key_generate_id(value, vlen, "", 0);
+		if (IS_ERR(kid))
+			return PTR_ERR(kid);
+		ctx->cert->sig->auth_ids[2] = kid;
+	}
+
 	return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
 }
 
@@ -501,9 +508,6 @@ int x509_extract_key_data(void *context, size_t hdrlen,
 			return -EBADMSG;
 
 		switch (oid) {
-		case OID_sm2:
-			ctx->cert->pub->pkey_algo = "sm2";
-			break;
 		case OID_id_prime192v1:
 			ctx->cert->pub->pkey_algo = "ecdsa-nist-p192";
 			break;
@@ -513,6 +517,9 @@ int x509_extract_key_data(void *context, size_t hdrlen,
 		case OID_id_ansip384r1:
 			ctx->cert->pub->pkey_algo = "ecdsa-nist-p384";
 			break;
+		case OID_id_ansip521r1:
+			ctx->cert->pub->pkey_algo = "ecdsa-nist-p521";
+			break;
 		default:
 			return -ENOPKG;
 		}
@@ -564,6 +571,34 @@ int x509_process_extension(void *context, size_t hdrlen,
 		return 0;
 	}
 
+	if (ctx->last_oid == OID_keyUsage) {
+		/*
+		 * Get hold of the keyUsage bit string
+		 * v[1] is the encoding size
+		 *       (Expect either 0x02 or 0x03, making it 1 or 2 bytes)
+		 * v[2] is the number of unused bits in the bit string
+		 *       (If >= 3 keyCertSign is missing when v[1] = 0x02)
+		 * v[3] and possibly v[4] contain the bit string
+		 *
+		 * From RFC 5280 4.2.1.3:
+		 *   0x04 is where keyCertSign lands in this bit string
+		 *   0x80 is where digitalSignature lands in this bit string
+		 */
+		if (v[0] != ASN1_BTS)
+			return -EBADMSG;
+		if (vlen < 4)
+			return -EBADMSG;
+		if (v[2] >= 8)
+			return -EBADMSG;
+		if (v[3] & 0x80)
+			ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_DIGITALSIG;
+		if (v[1] == 0x02 && v[2] <= 2 && (v[3] & 0x04))
+			ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN;
+		else if (vlen > 4 && v[1] == 0x03 && (v[3] & 0x04))
+			ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN;
+		return 0;
+	}
+
 	if (ctx->last_oid == OID_authorityKeyIdentifier) {
 		/* Get hold of the CA key fingerprint */
 		ctx->raw_akid = v;
@@ -571,6 +606,36 @@ int x509_process_extension(void *context, size_t hdrlen,
 		return 0;
 	}
 
+	if (ctx->last_oid == OID_basicConstraints) {
+		/*
+		 * Get hold of the basicConstraints
+		 * v[1] is the encoding size
+		 *	(Expect 0x00 for empty SEQUENCE with CA:FALSE, or
+		 *	0x03 or greater for non-empty SEQUENCE)
+		 * v[2] is the encoding type
+		 *	(Expect an ASN1_BOOL for the CA)
+		 * v[3] is the length of the ASN1_BOOL
+		 *	(Expect 1 for a single byte boolean)
+		 * v[4] is the contents of the ASN1_BOOL
+		 *	(Expect 0xFF if the CA is TRUE)
+		 * vlen should match the entire extension size
+		 */
+		if (v[0] != (ASN1_CONS_BIT | ASN1_SEQ))
+			return -EBADMSG;
+		if (vlen < 2)
+			return -EBADMSG;
+		if (v[1] != vlen - 2)
+			return -EBADMSG;
+		/* Empty SEQUENCE means CA:FALSE (default value omitted per DER) */
+		if (v[1] == 0)
+			return 0;
+		if (vlen >= 5 && v[2] == ASN1_BOOL && v[3] == 1 && v[4] == 0xFF)
+			ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_CA;
+		else
+			return -EBADMSG;
+		return 0;
+	}
+
 	return 0;
 }