linux/crypto/asymmetric_keys/x509_cert_parser.c

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/* X.509 certificate 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) "X.509: "fmt
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/oid_registry.h>
#include <crypto/public_key.h>
#include "x509_parser.h"
#include "x509-asn1.h"
#include "x509_akid-asn1.h"
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 */
enum OID last_oid; /* Last OID encountered */
enum OID algo_oid; /* Algorithm OID */
unsigned char nr_mpi; /* Number of MPIs stored */
u8 o_size; /* Size of organizationName (O) */
u8 cn_size; /* Size of commonName (CN) */
u8 email_size; /* Size of emailAddress */
u16 o_offset; /* Offset of organizationName (O) */
u16 cn_offset; /* Offset of commonName (CN) */
u16 email_offset; /* Offset of emailAddress */
unsigned raw_akid_size;
const void *raw_akid; /* Raw authorityKeyId in ASN.1 */
const void *akid_raw_issuer; /* Raw directoryName in authorityKeyId */
unsigned akid_raw_issuer_size;
};
/*
* Free an X.509 certificate
*/
void x509_free_certificate(struct x509_certificate *cert)
{
if (cert) {
public_key_free(cert->pub);
public_key_signature_free(cert->sig);
kfree(cert->issuer);
kfree(cert->subject);
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
kfree(cert->id);
kfree(cert->skid);
kfree(cert);
}
}
EXPORT_SYMBOL_GPL(x509_free_certificate);
/*
* Parse an X.509 certificate
*/
struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
{
struct x509_certificate *cert;
struct x509_parse_context *ctx;
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
struct asymmetric_key_id *kid;
long ret;
ret = -ENOMEM;
cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL);
if (!cert)
goto error_no_cert;
cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
if (!cert->pub)
goto error_no_ctx;
cert->sig = kzalloc(sizeof(struct public_key_signature), GFP_KERNEL);
if (!cert->sig)
goto error_no_ctx;
ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
if (!ctx)
goto error_no_ctx;
ctx->cert = cert;
ctx->data = (unsigned long)data;
/* Attempt to decode the certificate */
ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen);
if (ret < 0)
goto error_decode;
/* Decode the AuthorityKeyIdentifier */
if (ctx->raw_akid) {
pr_devel("AKID: %u %*phN\n",
ctx->raw_akid_size, ctx->raw_akid_size, ctx->raw_akid);
ret = asn1_ber_decoder(&x509_akid_decoder, ctx,
ctx->raw_akid, ctx->raw_akid_size);
if (ret < 0) {
pr_warn("Couldn't decode AuthKeyIdentifier\n");
goto error_decode;
}
}
ret = -ENOMEM;
cert->pub->key = kmemdup(ctx->key, ctx->key_size, GFP_KERNEL);
if (!cert->pub->key)
goto error_decode;
cert->pub->keylen = ctx->key_size;
/* Grab the signature bits */
ret = x509_get_sig_params(cert);
if (ret < 0)
goto error_decode;
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
/* 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;
}
cert->id = kid;
/* Detect self-signed certificates */
ret = x509_check_for_self_signed(cert);
if (ret < 0)
goto error_decode;
kfree(ctx);
return cert;
error_decode:
kfree(ctx);
error_no_ctx:
x509_free_certificate(cert);
error_no_cert:
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(x509_cert_parse);
/*
* Note an OID when we find one for later processing when we know how
* to interpret it.
*/
int x509_note_OID(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_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));
pr_debug("Unknown OID: [%lu] %s\n",
(unsigned long)value - ctx->data, buffer);
}
return 0;
}
/*
* Save the position of the TBS data so that we can check the signature over it
* later.
*/
int x509_note_tbs_certificate(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n",
hdrlen, tag, (unsigned long)value - ctx->data, vlen);
ctx->cert->tbs = value - hdrlen;
ctx->cert->tbs_size = vlen + hdrlen;
return 0;
}
/*
* Record the public key algorithm
*/
int x509_note_pkey_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";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha1WithRSAEncryption:
ctx->cert->sig->hash_algo = "sha1";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha256WithRSAEncryption:
ctx->cert->sig->hash_algo = "sha256";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha384WithRSAEncryption:
ctx->cert->sig->hash_algo = "sha384";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha512WithRSAEncryption:
ctx->cert->sig->hash_algo = "sha512";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha224WithRSAEncryption:
ctx->cert->sig->hash_algo = "sha224";
ctx->cert->sig->pkey_algo = "rsa";
break;
}
ctx->algo_oid = ctx->last_oid;
return 0;
}
/*
* Note the whereabouts and type of the signature.
*/
int x509_note_signature(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
pr_debug("Signature type: %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);
return -EINVAL;
}
ctx->cert->raw_sig = value;
ctx->cert->raw_sig_size = vlen;
return 0;
}
/*
* Note the certificate serial number
*/
int x509_note_serial(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
ctx->cert->raw_serial = value;
ctx->cert->raw_serial_size = vlen;
return 0;
}
/*
* Note some of the name segments from which we'll fabricate a name.
*/
int x509_extract_name_segment(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
switch (ctx->last_oid) {
case OID_commonName:
ctx->cn_size = vlen;
ctx->cn_offset = (unsigned long)value - ctx->data;
break;
case OID_organizationName:
ctx->o_size = vlen;
ctx->o_offset = (unsigned long)value - ctx->data;
break;
case OID_email_address:
ctx->email_size = vlen;
ctx->email_offset = (unsigned long)value - ctx->data;
break;
default:
break;
}
return 0;
}
/*
* Fabricate and save the issuer and subject names
*/
static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen,
unsigned char tag,
char **_name, size_t vlen)
{
const void *name, *data = (const void *)ctx->data;
size_t namesize;
char *buffer;
if (*_name)
return -EINVAL;
/* Empty name string if no material */
if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) {
buffer = kmalloc(1, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
buffer[0] = 0;
goto done;
}
if (ctx->cn_size && ctx->o_size) {
/* Consider combining O and CN, but use only the CN if it is
* prefixed by the O, or a significant portion thereof.
*/
namesize = ctx->cn_size;
name = data + ctx->cn_offset;
if (ctx->cn_size >= ctx->o_size &&
memcmp(data + ctx->cn_offset, data + ctx->o_offset,
ctx->o_size) == 0)
goto single_component;
if (ctx->cn_size >= 7 &&
ctx->o_size >= 7 &&
memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0)
goto single_component;
buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1,
GFP_KERNEL);
if (!buffer)
return -ENOMEM;
memcpy(buffer,
data + ctx->o_offset, ctx->o_size);
buffer[ctx->o_size + 0] = ':';
buffer[ctx->o_size + 1] = ' ';
memcpy(buffer + ctx->o_size + 2,
data + ctx->cn_offset, ctx->cn_size);
buffer[ctx->o_size + 2 + ctx->cn_size] = 0;
goto done;
} else if (ctx->cn_size) {
namesize = ctx->cn_size;
name = data + ctx->cn_offset;
} else if (ctx->o_size) {
namesize = ctx->o_size;
name = data + ctx->o_offset;
} else {
namesize = ctx->email_size;
name = data + ctx->email_offset;
}
single_component:
buffer = kmalloc(namesize + 1, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
memcpy(buffer, name, namesize);
buffer[namesize] = 0;
done:
*_name = buffer;
ctx->cn_size = 0;
ctx->o_size = 0;
ctx->email_size = 0;
return 0;
}
int x509_note_issuer(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
ctx->cert->raw_issuer = value;
ctx->cert->raw_issuer_size = vlen;
return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
}
int x509_note_subject(void *context, size_t hdrlen,
unsigned char tag,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
ctx->cert->raw_subject = value;
ctx->cert->raw_subject_size = vlen;
return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen);
}
/*
* 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;
if (ctx->last_oid != OID_rsaEncryption)
return -ENOPKG;
ctx->cert->pub->pkey_algo = "rsa";
/* Discard the BIT STRING metadata */
ctx->key = value + 1;
ctx->key_size = vlen - 1;
return 0;
}
X.509: Support parse long form of length octets in Authority Key Identifier Per X.509 spec in 4.2.1.1 section, the structure of Authority Key Identifier Extension is: AuthorityKeyIdentifier ::= SEQUENCE { keyIdentifier [0] KeyIdentifier OPTIONAL, authorityCertIssuer [1] GeneralNames OPTIONAL, authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL } KeyIdentifier ::= OCTET STRING When a certificate also provides authorityCertIssuer and authorityCertSerialNumber then the length of AuthorityKeyIdentifier SEQUENCE is likely to long form format. e.g. The example certificate demos/tunala/A-server.pem in openssl source: X509v3 Authority Key Identifier: keyid:49:FB:45:72:12:C4:CC:E1:45:A1:D3:08:9E:95:C4:2C:6D:55:3F:17 DirName:/C=NZ/L=Wellington/O=Really Irresponsible Authorisation Authority (RIAA)/OU=Cert-stamping/CN=Jackov al-Trades/emailAddress=none@fake.domain serial:00 Current parsing rule of OID_authorityKeyIdentifier only take care the short form format, it causes load certificate to modsign_keyring fail: [ 12.061147] X.509: Extension: 47 [ 12.075121] MODSIGN: Problem loading in-kernel X.509 certificate (-74) So, this patch add the parsing rule for support long form format against Authority Key Identifier. v3: Changed the size check in "Short Form length" case, we allow v[3] smaller then (vlen - 4) because authorityCertIssuer and authorityCertSerialNumber are also possible attach in AuthorityKeyIdentifier sequence. v2: - Removed comma from author's name. - Moved 'Short Form length' comment inside the if-body. - Changed the type of sub to size_t. - Use ASN1_INDEFINITE_LENGTH rather than writing 0x80 and 127. - Moved the key_len's value assignment before alter v. - Fixed the typo of octets. - Add 2 to v before entering the loop for calculate the length. - Removed the comment of check vlen. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Josh Boyer <jwboyer@redhat.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Chun-Yi Lee <jlee@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-22 03:26:55 +02:00
/* 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;
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
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 */
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
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);
KEYS: Overhaul key identification when searching for asymmetric keys 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>
2014-09-16 18:36:13 +02:00
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_authorityKeyIdentifier) {
/* Get hold of the CA key fingerprint */
ctx->raw_akid = v;
ctx->raw_akid_size = vlen;
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;
X.509: Fix the time validation [ver #2] This fixes CVE-2015-5327. It affects kernels from 4.3-rc1 onwards. Fix the X.509 time validation to use month number-1 when looking up the number of days in that month. Also put the month number validation before doing the lookup so as not to risk overrunning the array. This can be tested by doing the following: cat <<EOF | openssl x509 -outform DER | keyctl padd asymmetric "" @s -----BEGIN CERTIFICATE----- MIIDbjCCAlagAwIBAgIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAMCkxETAPBgNV BAoMCGxvY2FsLWNhMRQwEgYDVQQDDAtzaWduaW5nIGtleTAeFw0xNTA5MDEyMTMw MThaFw0xNjA4MzEyMTMwMThaMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQwEgYDVQQD DAtzaWduaW5nIGtleTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANrn crcMfMeG67nagX4+m02Xk9rkmsMKI5XTUxbikROe7GSUVJ27sPVPZp4mgzoWlvhh jfK8CC/qhEhwep8Pgg4EJZyWOjhZb7R97ckGvLIoUC6IO3FC2ZnR7WtmWDgo2Jcj VlXwJdHhKU1VZwulh81O61N8IBKqz2r/kDhIWiicUCUkI/Do/RMRfKAoDBcSh86m gOeIAGfq62vbiZhVsX5dOE8Oo2TK5weAvwUIOR7OuGBl5AqwFlPnXQolewiHzKry THg9e44HfzG4Mi6wUvcJxVaQT1h5SrKD779Z5+8+wf1JLaooetcEUArvWyuxCU59 qxA4lsTjBwl4cmEki+cCAwEAAaOBmDCBlTAMBgNVHRMEBTADAQH/MAsGA1UdDwQE AwIHgDAdBgNVHQ4EFgQUyND/eKUis7ep/hXMJ8iZMdUhI+IwWQYDVR0jBFIwUIAU yND/eKUis7ep/hXMJ8iZMdUhI+KhLaQrMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQw EgYDVQQDDAtzaWduaW5nIGtleYIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAA4IB AQAMqm1N1yD5pimUELLhT5eO2lRdGUfTozljRxc7e2QT3RLk2TtGhg65JFFN6eml XS58AEPVcAsSLDlR6WpOpOLB2giM0+fV/eYFHHmh22yqTJl4YgkdUwyzPdCHNOZL hmSKeY9xliHb6PNrNWWtZwhYYvRaO2DX4GXOMR0Oa2O4vaYu6/qGlZOZv3U6qZLY wwHEJSrqeBDyMuwN+eANHpoSpiBzD77S4e+7hUDJnql4j6xzJ65+nWJ89fCrQypR 4sN5R3aGeIh3QAQUIKpHilwek0CtEaYERgc5m+jGyKSc1rezJW62hWRTaitOc+d5 G5hh+9YpnYcxQHEKnZ7rFNKJ -----END CERTIFICATE----- EOF If it works, it emit a key ID; if it fails, it should give a bad message error. Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-11-12 10:36:40 +01:00
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;
}
}
}
X.509: Fix the time validation [ver #2] This fixes CVE-2015-5327. It affects kernels from 4.3-rc1 onwards. Fix the X.509 time validation to use month number-1 when looking up the number of days in that month. Also put the month number validation before doing the lookup so as not to risk overrunning the array. This can be tested by doing the following: cat <<EOF | openssl x509 -outform DER | keyctl padd asymmetric "" @s -----BEGIN CERTIFICATE----- MIIDbjCCAlagAwIBAgIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAMCkxETAPBgNV BAoMCGxvY2FsLWNhMRQwEgYDVQQDDAtzaWduaW5nIGtleTAeFw0xNTA5MDEyMTMw MThaFw0xNjA4MzEyMTMwMThaMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQwEgYDVQQD DAtzaWduaW5nIGtleTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANrn crcMfMeG67nagX4+m02Xk9rkmsMKI5XTUxbikROe7GSUVJ27sPVPZp4mgzoWlvhh jfK8CC/qhEhwep8Pgg4EJZyWOjhZb7R97ckGvLIoUC6IO3FC2ZnR7WtmWDgo2Jcj VlXwJdHhKU1VZwulh81O61N8IBKqz2r/kDhIWiicUCUkI/Do/RMRfKAoDBcSh86m gOeIAGfq62vbiZhVsX5dOE8Oo2TK5weAvwUIOR7OuGBl5AqwFlPnXQolewiHzKry THg9e44HfzG4Mi6wUvcJxVaQT1h5SrKD779Z5+8+wf1JLaooetcEUArvWyuxCU59 qxA4lsTjBwl4cmEki+cCAwEAAaOBmDCBlTAMBgNVHRMEBTADAQH/MAsGA1UdDwQE AwIHgDAdBgNVHQ4EFgQUyND/eKUis7ep/hXMJ8iZMdUhI+IwWQYDVR0jBFIwUIAU yND/eKUis7ep/hXMJ8iZMdUhI+KhLaQrMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQw EgYDVQQDDAtzaWduaW5nIGtleYIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAA4IB AQAMqm1N1yD5pimUELLhT5eO2lRdGUfTozljRxc7e2QT3RLk2TtGhg65JFFN6eml XS58AEPVcAsSLDlR6WpOpOLB2giM0+fV/eYFHHmh22yqTJl4YgkdUwyzPdCHNOZL hmSKeY9xliHb6PNrNWWtZwhYYvRaO2DX4GXOMR0Oa2O4vaYu6/qGlZOZv3U6qZLY wwHEJSrqeBDyMuwN+eANHpoSpiBzD77S4e+7hUDJnql4j6xzJ65+nWJ89fCrQypR 4sN5R3aGeIh3QAQUIKpHilwek0CtEaYERgc5m+jGyKSc1rezJW62hWRTaitOc+d5 G5hh+9YpnYcxQHEKnZ7rFNKJ -----END CERTIFICATE----- EOF If it works, it emit a key ID; if it fails, it should give a bad message error. Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-11-12 10:36:40 +01:00
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;
X.509: Fix the time validation [ver #2] This fixes CVE-2015-5327. It affects kernels from 4.3-rc1 onwards. Fix the X.509 time validation to use month number-1 when looking up the number of days in that month. Also put the month number validation before doing the lookup so as not to risk overrunning the array. This can be tested by doing the following: cat <<EOF | openssl x509 -outform DER | keyctl padd asymmetric "" @s -----BEGIN CERTIFICATE----- MIIDbjCCAlagAwIBAgIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAMCkxETAPBgNV BAoMCGxvY2FsLWNhMRQwEgYDVQQDDAtzaWduaW5nIGtleTAeFw0xNTA5MDEyMTMw MThaFw0xNjA4MzEyMTMwMThaMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQwEgYDVQQD DAtzaWduaW5nIGtleTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANrn crcMfMeG67nagX4+m02Xk9rkmsMKI5XTUxbikROe7GSUVJ27sPVPZp4mgzoWlvhh jfK8CC/qhEhwep8Pgg4EJZyWOjhZb7R97ckGvLIoUC6IO3FC2ZnR7WtmWDgo2Jcj VlXwJdHhKU1VZwulh81O61N8IBKqz2r/kDhIWiicUCUkI/Do/RMRfKAoDBcSh86m gOeIAGfq62vbiZhVsX5dOE8Oo2TK5weAvwUIOR7OuGBl5AqwFlPnXQolewiHzKry THg9e44HfzG4Mi6wUvcJxVaQT1h5SrKD779Z5+8+wf1JLaooetcEUArvWyuxCU59 qxA4lsTjBwl4cmEki+cCAwEAAaOBmDCBlTAMBgNVHRMEBTADAQH/MAsGA1UdDwQE AwIHgDAdBgNVHQ4EFgQUyND/eKUis7ep/hXMJ8iZMdUhI+IwWQYDVR0jBFIwUIAU yND/eKUis7ep/hXMJ8iZMdUhI+KhLaQrMCkxETAPBgNVBAoMCGxvY2FsLWNhMRQw EgYDVQQDDAtzaWduaW5nIGtleYIJAN/lUld+VR4hMA0GCSqGSIb3DQEBCwUAA4IB AQAMqm1N1yD5pimUELLhT5eO2lRdGUfTozljRxc7e2QT3RLk2TtGhg65JFFN6eml XS58AEPVcAsSLDlR6WpOpOLB2giM0+fV/eYFHHmh22yqTJl4YgkdUwyzPdCHNOZL hmSKeY9xliHb6PNrNWWtZwhYYvRaO2DX4GXOMR0Oa2O4vaYu6/qGlZOZv3U6qZLY wwHEJSrqeBDyMuwN+eANHpoSpiBzD77S4e+7hUDJnql4j6xzJ65+nWJ89fCrQypR 4sN5R3aGeIh3QAQUIKpHilwek0CtEaYERgc5m+jGyKSc1rezJW62hWRTaitOc+d5 G5hh+9YpnYcxQHEKnZ7rFNKJ -----END CERTIFICATE----- EOF If it works, it emit a key ID; if it fails, it should give a bad message error. Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-11-12 10:36:40 +01:00
*_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;
}