mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
46963b774d
Make use of the new match string preparsing to overhaul key identification when searching for asymmetric keys. The following changes are made: (1) Use the previously created asymmetric_key_id struct to hold the following key IDs derived from the X.509 certificate or PKCS#7 message: id: serial number + issuer skid: subjKeyId + subject authority: authKeyId + issuer (2) Replace the hex fingerprint attached to key->type_data[1] with an asymmetric_key_ids struct containing the id and the skid (if present). (3) Make the asymmetric_type match data preparse select one of two searches: (a) An iterative search for the key ID given if prefixed with "id:". The prefix is expected to be followed by a hex string giving the ID to search for. The criterion key ID is checked against all key IDs recorded on the key. (b) A direct search if the key ID is not prefixed with "id:". This will look for an exact match on the key description. (4) Make x509_request_asymmetric_key() take a key ID. This is then converted into "id:<hex>" and passed into keyring_search() where match preparsing will turn it back into a binary ID. (5) X.509 certificate verification then takes the authority key ID and looks up a key that matches it to find the public key for the certificate signature. (6) PKCS#7 certificate verification then takes the id key ID and looks up a key that matches it to find the public key for the signed information block signature. Additional changes: (1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the cert to be rejected with -EBADMSG. (2) The 'fingerprint' ID is gone. This was primarily intended to convey PGP public key fingerprints. If PGP is supported in future, this should generate a key ID that carries the fingerprint. (3) Th ca_keyid= kernel command line option is now converted to a key ID and used to match the authority key ID. Possibly this should only match the actual authKeyId part and not the issuer as well. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
418 lines
10 KiB
C
418 lines
10 KiB
C
/* PKCS#7 parser
|
|
*
|
|
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "PKCS7: "fmt
|
|
#include <linux/kernel.h>
|
|
#include <linux/export.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/err.h>
|
|
#include <linux/oid_registry.h>
|
|
#include "public_key.h"
|
|
#include "pkcs7_parser.h"
|
|
#include "pkcs7-asn1.h"
|
|
|
|
struct pkcs7_parse_context {
|
|
struct pkcs7_message *msg; /* Message being constructed */
|
|
struct pkcs7_signed_info *sinfo; /* SignedInfo being constructed */
|
|
struct pkcs7_signed_info **ppsinfo;
|
|
struct x509_certificate *certs; /* Certificate cache */
|
|
struct x509_certificate **ppcerts;
|
|
unsigned long data; /* Start of data */
|
|
enum OID last_oid; /* Last OID encountered */
|
|
unsigned x509_index;
|
|
unsigned sinfo_index;
|
|
const void *raw_serial;
|
|
unsigned raw_serial_size;
|
|
unsigned raw_issuer_size;
|
|
const void *raw_issuer;
|
|
};
|
|
|
|
/*
|
|
* Free a signed information block.
|
|
*/
|
|
static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo)
|
|
{
|
|
if (sinfo) {
|
|
mpi_free(sinfo->sig.mpi[0]);
|
|
kfree(sinfo->sig.digest);
|
|
kfree(sinfo->signing_cert_id);
|
|
kfree(sinfo);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* pkcs7_free_message - Free a PKCS#7 message
|
|
* @pkcs7: The PKCS#7 message to free
|
|
*/
|
|
void pkcs7_free_message(struct pkcs7_message *pkcs7)
|
|
{
|
|
struct x509_certificate *cert;
|
|
struct pkcs7_signed_info *sinfo;
|
|
|
|
if (pkcs7) {
|
|
while (pkcs7->certs) {
|
|
cert = pkcs7->certs;
|
|
pkcs7->certs = cert->next;
|
|
x509_free_certificate(cert);
|
|
}
|
|
while (pkcs7->crl) {
|
|
cert = pkcs7->crl;
|
|
pkcs7->crl = cert->next;
|
|
x509_free_certificate(cert);
|
|
}
|
|
while (pkcs7->signed_infos) {
|
|
sinfo = pkcs7->signed_infos;
|
|
pkcs7->signed_infos = sinfo->next;
|
|
pkcs7_free_signed_info(sinfo);
|
|
}
|
|
kfree(pkcs7);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(pkcs7_free_message);
|
|
|
|
/**
|
|
* pkcs7_parse_message - Parse a PKCS#7 message
|
|
* @data: The raw binary ASN.1 encoded message to be parsed
|
|
* @datalen: The size of the encoded message
|
|
*/
|
|
struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen)
|
|
{
|
|
struct pkcs7_parse_context *ctx;
|
|
struct pkcs7_message *msg = ERR_PTR(-ENOMEM);
|
|
int ret;
|
|
|
|
ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL);
|
|
if (!ctx)
|
|
goto out_no_ctx;
|
|
ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL);
|
|
if (!ctx->msg)
|
|
goto out_no_msg;
|
|
ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
|
|
if (!ctx->sinfo)
|
|
goto out_no_sinfo;
|
|
|
|
ctx->data = (unsigned long)data;
|
|
ctx->ppcerts = &ctx->certs;
|
|
ctx->ppsinfo = &ctx->msg->signed_infos;
|
|
|
|
/* Attempt to decode the signature */
|
|
ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen);
|
|
if (ret < 0) {
|
|
msg = ERR_PTR(ret);
|
|
goto out;
|
|
}
|
|
|
|
msg = ctx->msg;
|
|
ctx->msg = NULL;
|
|
|
|
out:
|
|
while (ctx->certs) {
|
|
struct x509_certificate *cert = ctx->certs;
|
|
ctx->certs = cert->next;
|
|
x509_free_certificate(cert);
|
|
}
|
|
pkcs7_free_signed_info(ctx->sinfo);
|
|
out_no_sinfo:
|
|
pkcs7_free_message(ctx->msg);
|
|
out_no_msg:
|
|
kfree(ctx);
|
|
out_no_ctx:
|
|
return msg;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pkcs7_parse_message);
|
|
|
|
/**
|
|
* pkcs7_get_content_data - Get access to the PKCS#7 content
|
|
* @pkcs7: The preparsed PKCS#7 message to access
|
|
* @_data: Place to return a pointer to the data
|
|
* @_data_len: Place to return the data length
|
|
* @want_wrapper: True if the ASN.1 object header should be included in the data
|
|
*
|
|
* Get access to the data content of the PKCS#7 message, including, optionally,
|
|
* the header of the ASN.1 object that contains it. Returns -ENODATA if the
|
|
* data object was missing from the message.
|
|
*/
|
|
int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
|
|
const void **_data, size_t *_data_len,
|
|
bool want_wrapper)
|
|
{
|
|
size_t wrapper;
|
|
|
|
if (!pkcs7->data)
|
|
return -ENODATA;
|
|
|
|
wrapper = want_wrapper ? pkcs7->data_hdrlen : 0;
|
|
*_data = pkcs7->data - wrapper;
|
|
*_data_len = pkcs7->data_len + wrapper;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pkcs7_get_content_data);
|
|
|
|
/*
|
|
* Note an OID when we find one for later processing when we know how
|
|
* to interpret it.
|
|
*/
|
|
int pkcs7_note_OID(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
ctx->last_oid = look_up_OID(value, vlen);
|
|
if (ctx->last_oid == OID__NR) {
|
|
char buffer[50];
|
|
sprint_oid(value, vlen, buffer, sizeof(buffer));
|
|
printk("PKCS7: Unknown OID: [%lu] %s\n",
|
|
(unsigned long)value - ctx->data, buffer);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note the digest algorithm for the signature.
|
|
*/
|
|
int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
switch (ctx->last_oid) {
|
|
case OID_md4:
|
|
ctx->sinfo->sig.pkey_hash_algo = HASH_ALGO_MD4;
|
|
break;
|
|
case OID_md5:
|
|
ctx->sinfo->sig.pkey_hash_algo = HASH_ALGO_MD5;
|
|
break;
|
|
case OID_sha1:
|
|
ctx->sinfo->sig.pkey_hash_algo = HASH_ALGO_SHA1;
|
|
break;
|
|
case OID_sha256:
|
|
ctx->sinfo->sig.pkey_hash_algo = HASH_ALGO_SHA256;
|
|
break;
|
|
default:
|
|
printk("Unsupported digest algo: %u\n", ctx->last_oid);
|
|
return -ENOPKG;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note the public key algorithm for the signature.
|
|
*/
|
|
int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
switch (ctx->last_oid) {
|
|
case OID_rsaEncryption:
|
|
ctx->sinfo->sig.pkey_algo = PKEY_ALGO_RSA;
|
|
break;
|
|
default:
|
|
printk("Unsupported pkey algo: %u\n", ctx->last_oid);
|
|
return -ENOPKG;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Extract a certificate and store it in the context.
|
|
*/
|
|
int pkcs7_extract_cert(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
struct x509_certificate *x509;
|
|
|
|
if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) {
|
|
pr_debug("Cert began with tag %02x at %lu\n",
|
|
tag, (unsigned long)ctx - ctx->data);
|
|
return -EBADMSG;
|
|
}
|
|
|
|
/* We have to correct for the header so that the X.509 parser can start
|
|
* from the beginning. Note that since X.509 stipulates DER, there
|
|
* probably shouldn't be an EOC trailer - but it is in PKCS#7 (which
|
|
* stipulates BER).
|
|
*/
|
|
value -= hdrlen;
|
|
vlen += hdrlen;
|
|
|
|
if (((u8*)value)[1] == 0x80)
|
|
vlen += 2; /* Indefinite length - there should be an EOC */
|
|
|
|
x509 = x509_cert_parse(value, vlen);
|
|
if (IS_ERR(x509))
|
|
return PTR_ERR(x509);
|
|
|
|
x509->index = ++ctx->x509_index;
|
|
pr_debug("Got cert %u for %s\n", x509->index, x509->subject);
|
|
pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data);
|
|
|
|
*ctx->ppcerts = x509;
|
|
ctx->ppcerts = &x509->next;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Save the certificate list
|
|
*/
|
|
int pkcs7_note_certificate_list(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
pr_devel("Got cert list (%02x)\n", tag);
|
|
|
|
*ctx->ppcerts = ctx->msg->certs;
|
|
ctx->msg->certs = ctx->certs;
|
|
ctx->certs = NULL;
|
|
ctx->ppcerts = &ctx->certs;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Extract the data from the message and store that and its content type OID in
|
|
* the context.
|
|
*/
|
|
int pkcs7_note_data(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
pr_debug("Got data\n");
|
|
|
|
ctx->msg->data = value;
|
|
ctx->msg->data_len = vlen;
|
|
ctx->msg->data_hdrlen = hdrlen;
|
|
ctx->msg->data_type = ctx->last_oid;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Parse authenticated attributes
|
|
*/
|
|
int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
|
|
|
|
switch (ctx->last_oid) {
|
|
case OID_messageDigest:
|
|
if (tag != ASN1_OTS)
|
|
return -EBADMSG;
|
|
ctx->sinfo->msgdigest = value;
|
|
ctx->sinfo->msgdigest_len = vlen;
|
|
return 0;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note the set of auth attributes for digestion purposes [RFC2315 9.3]
|
|
*/
|
|
int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
|
|
/* We need to switch the 'CONT 0' to a 'SET OF' when we digest */
|
|
ctx->sinfo->authattrs = value - (hdrlen - 1);
|
|
ctx->sinfo->authattrs_len = vlen + (hdrlen - 1);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note the issuing certificate serial number
|
|
*/
|
|
int pkcs7_sig_note_serial(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
ctx->raw_serial = value;
|
|
ctx->raw_serial_size = vlen;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note the issuer's name
|
|
*/
|
|
int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
ctx->raw_issuer = value;
|
|
ctx->raw_issuer_size = vlen;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note the signature data
|
|
*/
|
|
int pkcs7_sig_note_signature(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
MPI mpi;
|
|
|
|
BUG_ON(ctx->sinfo->sig.pkey_algo != PKEY_ALGO_RSA);
|
|
|
|
mpi = mpi_read_raw_data(value, vlen);
|
|
if (!mpi)
|
|
return -ENOMEM;
|
|
|
|
ctx->sinfo->sig.mpi[0] = mpi;
|
|
ctx->sinfo->sig.nr_mpi = 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note a signature information block
|
|
*/
|
|
int pkcs7_note_signed_info(void *context, size_t hdrlen,
|
|
unsigned char tag,
|
|
const void *value, size_t vlen)
|
|
{
|
|
struct pkcs7_parse_context *ctx = context;
|
|
struct pkcs7_signed_info *sinfo = ctx->sinfo;
|
|
struct asymmetric_key_id *kid;
|
|
|
|
/* Generate cert issuer + serial number key ID */
|
|
kid = asymmetric_key_generate_id(ctx->raw_serial,
|
|
ctx->raw_serial_size,
|
|
ctx->raw_issuer,
|
|
ctx->raw_issuer_size);
|
|
if (IS_ERR(kid))
|
|
return PTR_ERR(kid);
|
|
|
|
sinfo->signing_cert_id = kid;
|
|
sinfo->index = ++ctx->sinfo_index;
|
|
*ctx->ppsinfo = sinfo;
|
|
ctx->ppsinfo = &sinfo->next;
|
|
ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
|
|
if (!ctx->sinfo)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|