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![Eric Snowberg](/assets/img/avatar_default.png)
Parse the X.509 Key Usage. The key usage extension defines the purpose of the key contained in the certificate. id-ce-keyUsage OBJECT IDENTIFIER ::= { id-ce 15 } KeyUsage ::= BIT STRING { digitalSignature (0), contentCommitment (1), keyEncipherment (2), dataEncipherment (3), keyAgreement (4), keyCertSign (5), cRLSign (6), encipherOnly (7), decipherOnly (8) } If the keyCertSign or digitalSignature is set, store it in the public_key structure. Having the purpose of the key being stored during parsing, allows enforcement on the usage field in the future. This will be used in a follow on patch that requires knowing the certificate key usage type. Link: https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.3 Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
817 lines
20 KiB
C
817 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* X.509 certificate parser
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*
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* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*/
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#define pr_fmt(fmt) "X.509: "fmt
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#include <linux/kernel.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/err.h>
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#include <linux/oid_registry.h>
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#include <crypto/public_key.h>
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#include "x509_parser.h"
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#include "x509.asn1.h"
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#include "x509_akid.asn1.h"
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struct x509_parse_context {
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struct x509_certificate *cert; /* Certificate being constructed */
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unsigned long data; /* Start of data */
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const void *key; /* Key data */
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size_t key_size; /* Size of key data */
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const void *params; /* Key parameters */
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size_t params_size; /* Size of key parameters */
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enum OID key_algo; /* Algorithm used by the cert's key */
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enum OID last_oid; /* Last OID encountered */
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enum OID sig_algo; /* Algorithm used to sign the cert */
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u8 o_size; /* Size of organizationName (O) */
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u8 cn_size; /* Size of commonName (CN) */
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u8 email_size; /* Size of emailAddress */
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u16 o_offset; /* Offset of organizationName (O) */
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u16 cn_offset; /* Offset of commonName (CN) */
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u16 email_offset; /* Offset of emailAddress */
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unsigned raw_akid_size;
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const void *raw_akid; /* Raw authorityKeyId in ASN.1 */
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const void *akid_raw_issuer; /* Raw directoryName in authorityKeyId */
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unsigned akid_raw_issuer_size;
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};
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/*
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* Free an X.509 certificate
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*/
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void x509_free_certificate(struct x509_certificate *cert)
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{
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if (cert) {
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public_key_free(cert->pub);
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public_key_signature_free(cert->sig);
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kfree(cert->issuer);
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kfree(cert->subject);
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kfree(cert->id);
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kfree(cert->skid);
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kfree(cert);
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}
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}
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EXPORT_SYMBOL_GPL(x509_free_certificate);
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/*
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* Parse an X.509 certificate
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*/
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struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
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{
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struct x509_certificate *cert;
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struct x509_parse_context *ctx;
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struct asymmetric_key_id *kid;
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long ret;
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ret = -ENOMEM;
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cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL);
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if (!cert)
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goto error_no_cert;
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cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
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if (!cert->pub)
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goto error_no_ctx;
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cert->sig = kzalloc(sizeof(struct public_key_signature), GFP_KERNEL);
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if (!cert->sig)
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goto error_no_ctx;
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ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
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if (!ctx)
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goto error_no_ctx;
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ctx->cert = cert;
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ctx->data = (unsigned long)data;
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/* Attempt to decode the certificate */
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ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen);
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if (ret < 0)
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goto error_decode;
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/* Decode the AuthorityKeyIdentifier */
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if (ctx->raw_akid) {
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pr_devel("AKID: %u %*phN\n",
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ctx->raw_akid_size, ctx->raw_akid_size, ctx->raw_akid);
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ret = asn1_ber_decoder(&x509_akid_decoder, ctx,
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ctx->raw_akid, ctx->raw_akid_size);
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if (ret < 0) {
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pr_warn("Couldn't decode AuthKeyIdentifier\n");
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goto error_decode;
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}
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}
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ret = -ENOMEM;
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cert->pub->key = kmemdup(ctx->key, ctx->key_size, GFP_KERNEL);
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if (!cert->pub->key)
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goto error_decode;
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cert->pub->keylen = ctx->key_size;
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cert->pub->params = kmemdup(ctx->params, ctx->params_size, GFP_KERNEL);
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if (!cert->pub->params)
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goto error_decode;
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cert->pub->paramlen = ctx->params_size;
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cert->pub->algo = ctx->key_algo;
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/* Grab the signature bits */
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ret = x509_get_sig_params(cert);
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if (ret < 0)
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goto error_decode;
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/* Generate cert issuer + serial number key ID */
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kid = asymmetric_key_generate_id(cert->raw_serial,
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cert->raw_serial_size,
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cert->raw_issuer,
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cert->raw_issuer_size);
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if (IS_ERR(kid)) {
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ret = PTR_ERR(kid);
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goto error_decode;
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}
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cert->id = kid;
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/* Detect self-signed certificates */
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ret = x509_check_for_self_signed(cert);
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if (ret < 0)
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goto error_decode;
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kfree(ctx);
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return cert;
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error_decode:
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kfree(ctx);
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error_no_ctx:
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x509_free_certificate(cert);
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error_no_cert:
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return ERR_PTR(ret);
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}
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EXPORT_SYMBOL_GPL(x509_cert_parse);
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/*
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* Note an OID when we find one for later processing when we know how
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* to interpret it.
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*/
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int x509_note_OID(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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ctx->last_oid = look_up_OID(value, vlen);
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if (ctx->last_oid == OID__NR) {
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char buffer[50];
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sprint_oid(value, vlen, buffer, sizeof(buffer));
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pr_debug("Unknown OID: [%lu] %s\n",
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(unsigned long)value - ctx->data, buffer);
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}
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return 0;
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}
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/*
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* Save the position of the TBS data so that we can check the signature over it
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* later.
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*/
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int x509_note_tbs_certificate(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n",
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hdrlen, tag, (unsigned long)value - ctx->data, vlen);
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ctx->cert->tbs = value - hdrlen;
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ctx->cert->tbs_size = vlen + hdrlen;
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return 0;
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}
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/*
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* Record the algorithm that was used to sign this certificate.
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*/
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int x509_note_sig_algo(void *context, size_t hdrlen, unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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pr_debug("PubKey Algo: %u\n", ctx->last_oid);
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switch (ctx->last_oid) {
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case OID_md2WithRSAEncryption:
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case OID_md3WithRSAEncryption:
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default:
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return -ENOPKG; /* Unsupported combination */
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case OID_md4WithRSAEncryption:
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ctx->cert->sig->hash_algo = "md4";
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goto rsa_pkcs1;
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case OID_sha1WithRSAEncryption:
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ctx->cert->sig->hash_algo = "sha1";
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goto rsa_pkcs1;
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case OID_sha256WithRSAEncryption:
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ctx->cert->sig->hash_algo = "sha256";
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goto rsa_pkcs1;
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case OID_sha384WithRSAEncryption:
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ctx->cert->sig->hash_algo = "sha384";
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goto rsa_pkcs1;
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case OID_sha512WithRSAEncryption:
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ctx->cert->sig->hash_algo = "sha512";
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goto rsa_pkcs1;
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case OID_sha224WithRSAEncryption:
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ctx->cert->sig->hash_algo = "sha224";
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goto rsa_pkcs1;
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case OID_id_ecdsa_with_sha1:
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ctx->cert->sig->hash_algo = "sha1";
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goto ecdsa;
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case OID_id_ecdsa_with_sha224:
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ctx->cert->sig->hash_algo = "sha224";
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goto ecdsa;
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case OID_id_ecdsa_with_sha256:
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ctx->cert->sig->hash_algo = "sha256";
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goto ecdsa;
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case OID_id_ecdsa_with_sha384:
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ctx->cert->sig->hash_algo = "sha384";
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goto ecdsa;
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case OID_id_ecdsa_with_sha512:
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ctx->cert->sig->hash_algo = "sha512";
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goto ecdsa;
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case OID_gost2012Signature256:
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ctx->cert->sig->hash_algo = "streebog256";
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goto ecrdsa;
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case OID_gost2012Signature512:
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ctx->cert->sig->hash_algo = "streebog512";
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goto ecrdsa;
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case OID_SM2_with_SM3:
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ctx->cert->sig->hash_algo = "sm3";
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goto sm2;
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}
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rsa_pkcs1:
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ctx->cert->sig->pkey_algo = "rsa";
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ctx->cert->sig->encoding = "pkcs1";
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ctx->sig_algo = ctx->last_oid;
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return 0;
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ecrdsa:
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ctx->cert->sig->pkey_algo = "ecrdsa";
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ctx->cert->sig->encoding = "raw";
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ctx->sig_algo = ctx->last_oid;
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return 0;
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sm2:
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ctx->cert->sig->pkey_algo = "sm2";
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ctx->cert->sig->encoding = "raw";
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ctx->sig_algo = ctx->last_oid;
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return 0;
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ecdsa:
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ctx->cert->sig->pkey_algo = "ecdsa";
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ctx->cert->sig->encoding = "x962";
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ctx->sig_algo = ctx->last_oid;
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return 0;
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}
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/*
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* Note the whereabouts and type of the signature.
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*/
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int x509_note_signature(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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pr_debug("Signature: alg=%u, size=%zu\n", ctx->last_oid, vlen);
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/*
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* In X.509 certificates, the signature's algorithm is stored in two
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* places: inside the TBSCertificate (the data that is signed), and
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* alongside the signature. These *must* match.
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*/
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if (ctx->last_oid != ctx->sig_algo) {
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pr_warn("signatureAlgorithm (%u) differs from tbsCertificate.signature (%u)\n",
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ctx->last_oid, ctx->sig_algo);
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return -EINVAL;
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}
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if (strcmp(ctx->cert->sig->pkey_algo, "rsa") == 0 ||
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strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0 ||
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strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0 ||
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strcmp(ctx->cert->sig->pkey_algo, "ecdsa") == 0) {
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/* Discard the BIT STRING metadata */
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if (vlen < 1 || *(const u8 *)value != 0)
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return -EBADMSG;
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value++;
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vlen--;
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}
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ctx->cert->raw_sig = value;
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ctx->cert->raw_sig_size = vlen;
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return 0;
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}
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/*
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* Note the certificate serial number
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*/
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int x509_note_serial(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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ctx->cert->raw_serial = value;
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ctx->cert->raw_serial_size = vlen;
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return 0;
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}
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/*
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* Note some of the name segments from which we'll fabricate a name.
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*/
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int x509_extract_name_segment(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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switch (ctx->last_oid) {
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case OID_commonName:
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ctx->cn_size = vlen;
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ctx->cn_offset = (unsigned long)value - ctx->data;
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break;
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case OID_organizationName:
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ctx->o_size = vlen;
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ctx->o_offset = (unsigned long)value - ctx->data;
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break;
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case OID_email_address:
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ctx->email_size = vlen;
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ctx->email_offset = (unsigned long)value - ctx->data;
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break;
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default:
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break;
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}
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return 0;
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}
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/*
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* Fabricate and save the issuer and subject names
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*/
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static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen,
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unsigned char tag,
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char **_name, size_t vlen)
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{
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const void *name, *data = (const void *)ctx->data;
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size_t namesize;
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char *buffer;
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if (*_name)
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return -EINVAL;
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/* Empty name string if no material */
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if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) {
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buffer = kmalloc(1, GFP_KERNEL);
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if (!buffer)
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return -ENOMEM;
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buffer[0] = 0;
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goto done;
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}
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if (ctx->cn_size && ctx->o_size) {
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/* Consider combining O and CN, but use only the CN if it is
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* prefixed by the O, or a significant portion thereof.
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*/
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namesize = ctx->cn_size;
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name = data + ctx->cn_offset;
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if (ctx->cn_size >= ctx->o_size &&
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memcmp(data + ctx->cn_offset, data + ctx->o_offset,
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ctx->o_size) == 0)
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goto single_component;
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if (ctx->cn_size >= 7 &&
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ctx->o_size >= 7 &&
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memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0)
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goto single_component;
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buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1,
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GFP_KERNEL);
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if (!buffer)
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return -ENOMEM;
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memcpy(buffer,
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data + ctx->o_offset, ctx->o_size);
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buffer[ctx->o_size + 0] = ':';
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buffer[ctx->o_size + 1] = ' ';
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memcpy(buffer + ctx->o_size + 2,
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data + ctx->cn_offset, ctx->cn_size);
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buffer[ctx->o_size + 2 + ctx->cn_size] = 0;
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goto done;
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} else if (ctx->cn_size) {
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namesize = ctx->cn_size;
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name = data + ctx->cn_offset;
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} else if (ctx->o_size) {
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namesize = ctx->o_size;
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name = data + ctx->o_offset;
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} else {
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namesize = ctx->email_size;
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name = data + ctx->email_offset;
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}
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single_component:
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buffer = kmalloc(namesize + 1, GFP_KERNEL);
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if (!buffer)
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return -ENOMEM;
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memcpy(buffer, name, namesize);
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buffer[namesize] = 0;
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done:
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*_name = buffer;
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ctx->cn_size = 0;
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ctx->o_size = 0;
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ctx->email_size = 0;
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return 0;
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}
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int x509_note_issuer(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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struct asymmetric_key_id *kid;
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ctx->cert->raw_issuer = value;
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ctx->cert->raw_issuer_size = vlen;
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if (!ctx->cert->sig->auth_ids[2]) {
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kid = asymmetric_key_generate_id(value, vlen, "", 0);
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if (IS_ERR(kid))
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return PTR_ERR(kid);
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ctx->cert->sig->auth_ids[2] = kid;
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}
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return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
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}
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int x509_note_subject(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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ctx->cert->raw_subject = value;
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ctx->cert->raw_subject_size = vlen;
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return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen);
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}
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/*
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* Extract the parameters for the public key
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*/
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int x509_note_params(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct x509_parse_context *ctx = context;
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/*
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* AlgorithmIdentifier is used three times in the x509, we should skip
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* first and ignore third, using second one which is after subject and
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* before subjectPublicKey.
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*/
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if (!ctx->cert->raw_subject || ctx->key)
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return 0;
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ctx->params = value - hdrlen;
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ctx->params_size = vlen + hdrlen;
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return 0;
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}
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/*
|
|
* Extract the data for the public key algorithm
|
|
*/
|
|
int x509_extract_key_data(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
enum OID oid;
|
|
|
|
ctx->key_algo = ctx->last_oid;
|
|
switch (ctx->last_oid) {
|
|
case OID_rsaEncryption:
|
|
ctx->cert->pub->pkey_algo = "rsa";
|
|
break;
|
|
case OID_gost2012PKey256:
|
|
case OID_gost2012PKey512:
|
|
ctx->cert->pub->pkey_algo = "ecrdsa";
|
|
break;
|
|
case OID_sm2:
|
|
ctx->cert->pub->pkey_algo = "sm2";
|
|
break;
|
|
case OID_id_ecPublicKey:
|
|
if (parse_OID(ctx->params, ctx->params_size, &oid) != 0)
|
|
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;
|
|
case OID_id_prime256v1:
|
|
ctx->cert->pub->pkey_algo = "ecdsa-nist-p256";
|
|
break;
|
|
case OID_id_ansip384r1:
|
|
ctx->cert->pub->pkey_algo = "ecdsa-nist-p384";
|
|
break;
|
|
default:
|
|
return -ENOPKG;
|
|
}
|
|
break;
|
|
default:
|
|
return -ENOPKG;
|
|
}
|
|
|
|
/* Discard the BIT STRING metadata */
|
|
if (vlen < 1 || *(const u8 *)value != 0)
|
|
return -EBADMSG;
|
|
ctx->key = value + 1;
|
|
ctx->key_size = vlen - 1;
|
|
return 0;
|
|
}
|
|
|
|
/* The keyIdentifier in AuthorityKeyIdentifier SEQUENCE is tag(CONT,PRIM,0) */
|
|
#define SEQ_TAG_KEYID (ASN1_CONT << 6)
|
|
|
|
/*
|
|
* Process certificate extensions that are used to qualify the certificate.
|
|
*/
|
|
int x509_process_extension(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
struct asymmetric_key_id *kid;
|
|
const unsigned char *v = value;
|
|
|
|
pr_debug("Extension: %u\n", ctx->last_oid);
|
|
|
|
if (ctx->last_oid == OID_subjectKeyIdentifier) {
|
|
/* Get hold of the key fingerprint */
|
|
if (ctx->cert->skid || vlen < 3)
|
|
return -EBADMSG;
|
|
if (v[0] != ASN1_OTS || v[1] != vlen - 2)
|
|
return -EBADMSG;
|
|
v += 2;
|
|
vlen -= 2;
|
|
|
|
ctx->cert->raw_skid_size = vlen;
|
|
ctx->cert->raw_skid = v;
|
|
kid = asymmetric_key_generate_id(v, vlen, "", 0);
|
|
if (IS_ERR(kid))
|
|
return PTR_ERR(kid);
|
|
ctx->cert->skid = kid;
|
|
pr_debug("subjkeyid %*phN\n", kid->len, kid->data);
|
|
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;
|
|
ctx->raw_akid_size = vlen;
|
|
return 0;
|
|
}
|
|
|
|
if (ctx->last_oid == OID_basicConstraints) {
|
|
/*
|
|
* Get hold of the basicConstraints
|
|
* v[1] is the encoding size
|
|
* (Expect 0x2 or greater, making it 1 or more bytes)
|
|
* v[2] is the encoding type
|
|
* (Expect an ASN1_BOOL for the CA)
|
|
* v[3] is the contents of the ASN1_BOOL
|
|
* (Expect 1 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;
|
|
if (vlen >= 4 && v[1] != 0 && v[2] == ASN1_BOOL && v[3] == 1)
|
|
ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_CA;
|
|
return 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* x509_decode_time - Decode an X.509 time ASN.1 object
|
|
* @_t: The time to fill in
|
|
* @hdrlen: The length of the object header
|
|
* @tag: The object tag
|
|
* @value: The object value
|
|
* @vlen: The size of the object value
|
|
*
|
|
* Decode an ASN.1 universal time or generalised time field into a struct the
|
|
* kernel can handle and check it for validity. The time is decoded thus:
|
|
*
|
|
* [RFC5280 §4.1.2.5]
|
|
* CAs conforming to this profile MUST always encode certificate validity
|
|
* dates through the year 2049 as UTCTime; certificate validity dates in
|
|
* 2050 or later MUST be encoded as GeneralizedTime. Conforming
|
|
* applications MUST be able to process validity dates that are encoded in
|
|
* either UTCTime or GeneralizedTime.
|
|
*/
|
|
int x509_decode_time(time64_t *_t, size_t hdrlen,
|
|
unsigned char tag,
|
|
const unsigned char *value, size_t vlen)
|
|
{
|
|
static const unsigned char month_lengths[] = { 31, 28, 31, 30, 31, 30,
|
|
31, 31, 30, 31, 30, 31 };
|
|
const unsigned char *p = value;
|
|
unsigned year, mon, day, hour, min, sec, mon_len;
|
|
|
|
#define dec2bin(X) ({ unsigned char x = (X) - '0'; if (x > 9) goto invalid_time; x; })
|
|
#define DD2bin(P) ({ unsigned x = dec2bin(P[0]) * 10 + dec2bin(P[1]); P += 2; x; })
|
|
|
|
if (tag == ASN1_UNITIM) {
|
|
/* UTCTime: YYMMDDHHMMSSZ */
|
|
if (vlen != 13)
|
|
goto unsupported_time;
|
|
year = DD2bin(p);
|
|
if (year >= 50)
|
|
year += 1900;
|
|
else
|
|
year += 2000;
|
|
} else if (tag == ASN1_GENTIM) {
|
|
/* GenTime: YYYYMMDDHHMMSSZ */
|
|
if (vlen != 15)
|
|
goto unsupported_time;
|
|
year = DD2bin(p) * 100 + DD2bin(p);
|
|
if (year >= 1950 && year <= 2049)
|
|
goto invalid_time;
|
|
} else {
|
|
goto unsupported_time;
|
|
}
|
|
|
|
mon = DD2bin(p);
|
|
day = DD2bin(p);
|
|
hour = DD2bin(p);
|
|
min = DD2bin(p);
|
|
sec = DD2bin(p);
|
|
|
|
if (*p != 'Z')
|
|
goto unsupported_time;
|
|
|
|
if (year < 1970 ||
|
|
mon < 1 || mon > 12)
|
|
goto invalid_time;
|
|
|
|
mon_len = month_lengths[mon - 1];
|
|
if (mon == 2) {
|
|
if (year % 4 == 0) {
|
|
mon_len = 29;
|
|
if (year % 100 == 0) {
|
|
mon_len = 28;
|
|
if (year % 400 == 0)
|
|
mon_len = 29;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (day < 1 || day > mon_len ||
|
|
hour > 24 || /* ISO 8601 permits 24:00:00 as midnight tomorrow */
|
|
min > 59 ||
|
|
sec > 60) /* ISO 8601 permits leap seconds [X.680 46.3] */
|
|
goto invalid_time;
|
|
|
|
*_t = mktime64(year, mon, day, hour, min, sec);
|
|
return 0;
|
|
|
|
unsupported_time:
|
|
pr_debug("Got unsupported time [tag %02x]: '%*phN'\n",
|
|
tag, (int)vlen, value);
|
|
return -EBADMSG;
|
|
invalid_time:
|
|
pr_debug("Got invalid time [tag %02x]: '%*phN'\n",
|
|
tag, (int)vlen, value);
|
|
return -EBADMSG;
|
|
}
|
|
EXPORT_SYMBOL_GPL(x509_decode_time);
|
|
|
|
int x509_note_not_before(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
return x509_decode_time(&ctx->cert->valid_from, hdrlen, tag, value, vlen);
|
|
}
|
|
|
|
int x509_note_not_after(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
return x509_decode_time(&ctx->cert->valid_to, hdrlen, tag, value, vlen);
|
|
}
|
|
|
|
/*
|
|
* Note a key identifier-based AuthorityKeyIdentifier
|
|
*/
|
|
int x509_akid_note_kid(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
struct asymmetric_key_id *kid;
|
|
|
|
pr_debug("AKID: keyid: %*phN\n", (int)vlen, value);
|
|
|
|
if (ctx->cert->sig->auth_ids[1])
|
|
return 0;
|
|
|
|
kid = asymmetric_key_generate_id(value, vlen, "", 0);
|
|
if (IS_ERR(kid))
|
|
return PTR_ERR(kid);
|
|
pr_debug("authkeyid %*phN\n", kid->len, kid->data);
|
|
ctx->cert->sig->auth_ids[1] = kid;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note a directoryName in an AuthorityKeyIdentifier
|
|
*/
|
|
int x509_akid_note_name(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
|
|
pr_debug("AKID: name: %*phN\n", (int)vlen, value);
|
|
|
|
ctx->akid_raw_issuer = value;
|
|
ctx->akid_raw_issuer_size = vlen;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note a serial number in an AuthorityKeyIdentifier
|
|
*/
|
|
int x509_akid_note_serial(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct x509_parse_context *ctx = context;
|
|
struct asymmetric_key_id *kid;
|
|
|
|
pr_debug("AKID: serial: %*phN\n", (int)vlen, value);
|
|
|
|
if (!ctx->akid_raw_issuer || ctx->cert->sig->auth_ids[0])
|
|
return 0;
|
|
|
|
kid = asymmetric_key_generate_id(value,
|
|
vlen,
|
|
ctx->akid_raw_issuer,
|
|
ctx->akid_raw_issuer_size);
|
|
if (IS_ERR(kid))
|
|
return PTR_ERR(kid);
|
|
|
|
pr_debug("authkeyid %*phN\n", kid->len, kid->data);
|
|
ctx->cert->sig->auth_ids[0] = kid;
|
|
return 0;
|
|
}
|