[PATCH 7/9] KEYS: Overhaul key identification when searching for asymmetric keys

From: David Howells
Date: Fri Sep 12 2014 - 15:05:58 EST

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@xxxxxxxxxx>
---

crypto/asymmetric_keys/asymmetric_keys.h | 4 -
crypto/asymmetric_keys/asymmetric_type.c | 133 ++++++++++++-----------------
crypto/asymmetric_keys/pkcs7_parser.c | 38 ++++++--
crypto/asymmetric_keys/pkcs7_parser.h | 5 -
crypto/asymmetric_keys/pkcs7_trust.c | 6 -
crypto/asymmetric_keys/pkcs7_verify.c | 44 ++++------
crypto/asymmetric_keys/x509_cert_parser.c | 55 +++++++-----
crypto/asymmetric_keys/x509_parser.h | 5 +
crypto/asymmetric_keys/x509_public_key.c | 89 +++++++++++--------
include/crypto/public_key.h | 5 +
10 files changed, 198 insertions(+), 186 deletions(-)

diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h
index 917be6b985e7..fd21ac28e0a0 100644
--- a/crypto/asymmetric_keys/asymmetric_keys.h
+++ b/crypto/asymmetric_keys/asymmetric_keys.h
@@ -9,13 +9,13 @@
* 2 of the Licence, or (at your option) any later version.
*/

-int asymmetric_keyid_match(const char *kid, const char *id);
extern bool asymmetric_match_key_ids(const struct asymmetric_key_ids *kids,
const struct asymmetric_key_id *match_id);

extern struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id);

-static inline const char *asymmetric_key_id(const struct key *key)
+static inline
+const struct asymmetric_key_ids *asymmetric_key_ids(const struct key *key)
{
return key->type_data.p[1];
}
diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index 3bc71b4e1eed..6f16f647d21b 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -105,76 +105,15 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
}

/*
- * Match asymmetric key id with partial match
- * @id: key id to match in a form "id:<id>"
- */
-int asymmetric_keyid_match(const char *kid, const char *id)
-{
- size_t idlen, kidlen;
-
- if (!kid || !id)
- return 0;
-
- /* make it possible to use id as in the request: "id:<id>" */
- if (strncmp(id, "id:", 3) == 0)
- id += 3;
-
- /* Anything after here requires a partial match on the ID string */
- idlen = strlen(id);
- kidlen = strlen(kid);
- if (idlen > kidlen)
- return 0;
-
- kid += kidlen - idlen;
- if (strcasecmp(id, kid) != 0)
- return 0;
-
- return 1;
-}
-EXPORT_SYMBOL_GPL(asymmetric_keyid_match);
-
-/*
- * Match asymmetric keys on (part of) their name
- * We have some shorthand methods for matching keys. We allow:
- *
- * "<desc>" - request a key by description
- * "id:<id>" - request a key matching the ID
- * "<subtype>:<id>" - request a key of a subtype
+ * Match asymmetric keys by ID.
*/
static bool asymmetric_key_cmp(const struct key *key,
const struct key_match_data *match_data)
{
- const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
- const char *description = match_data->raw_data;
- const char *spec = description;
- const char *id;
- ptrdiff_t speclen;
-
- if (!subtype || !spec || !*spec)
- return 0;
-
- /* See if the full key description matches as is */
- if (key->description && strcmp(key->description, description) == 0)
- return 1;
-
- /* All tests from here on break the criterion description into a
- * specifier, a colon and then an identifier.
- */
- id = strchr(spec, ':');
- if (!id)
- return 0;
-
- speclen = id - spec;
- id++;
-
- if (speclen == 2 && memcmp(spec, "id", 2) == 0)
- return asymmetric_keyid_match(asymmetric_key_id(key), id);
+ const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+ const struct asymmetric_key_id *match_id = match_data->preparsed;

- if (speclen == subtype->name_len &&
- memcmp(spec, subtype->name, speclen) == 0)
- return 1;
-
- return 0;
+ return asymmetric_match_key_ids(kids, match_id);
}

/*
@@ -191,8 +130,30 @@ static bool asymmetric_key_cmp(const struct key *key,
*/
static int asymmetric_key_match_preparse(struct key_match_data *match_data)
{
- match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
+ struct asymmetric_key_id *match_id;
+ const char *spec = match_data->raw_data;
+ const char *id;
+
+ if (!spec || !*spec)
+ return -EINVAL;
+ if (spec[0] == 'i' &&
+ spec[1] == 'd' &&
+ spec[2] == ':') {
+ id = spec + 3;
+ } else {
+ goto default_match;
+ }
+
+ match_id = asymmetric_key_hex_to_key_id(id);
+ if (!match_id)
+ return -ENOMEM;
+
+ match_data->preparsed = match_id;
match_data->cmp = asymmetric_key_cmp;
+ match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
+ return 0;
+
+default_match:
return 0;
}

@@ -201,6 +162,7 @@ static int asymmetric_key_match_preparse(struct key_match_data *match_data)
*/
static void asymmetric_key_match_free(struct key_match_data *match_data)
{
+ kfree(match_data->preparsed);
}

/*
@@ -209,8 +171,10 @@ static void asymmetric_key_match_free(struct key_match_data *match_data)
static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
{
const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
- const char *kid = asymmetric_key_id(key);
- size_t n;
+ const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+ const struct asymmetric_key_id *kid;
+ const unsigned char *p;
+ int n;

seq_puts(m, key->description);

@@ -218,13 +182,16 @@ static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
seq_puts(m, ": ");
subtype->describe(key, m);

- if (kid) {
+ if (kids && kids->id[0]) {
+ kid = kids->id[0];
seq_putc(m, ' ');
- n = strlen(kid);
- if (n <= 8)
- seq_puts(m, kid);
- else
- seq_puts(m, kid + n - 8);
+ n = kid->len;
+ p = kid->data;
+ if (n > 8) {
+ p += n - 8;
+ n = 8;
+ }
+ seq_printf(m, "%*phN", n, p);
}

seq_puts(m, " [");
@@ -275,6 +242,7 @@ static int asymmetric_key_preparse(struct key_preparsed_payload *prep)
static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
{
struct asymmetric_key_subtype *subtype = prep->type_data[0];
+ struct asymmetric_key_ids *kids = prep->type_data[1];

pr_devel("==>%s()\n", __func__);

@@ -282,7 +250,11 @@ static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
subtype->destroy(prep->payload[0]);
module_put(subtype->owner);
}
- kfree(prep->type_data[1]);
+ if (kids) {
+ kfree(kids->id[0]);
+ kfree(kids->id[1]);
+ kfree(kids);
+ }
kfree(prep->description);
}

@@ -292,13 +264,20 @@ static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
static void asymmetric_key_destroy(struct key *key)
{
struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
+ struct asymmetric_key_ids *kids = key->type_data.p[1];
+
if (subtype) {
subtype->destroy(key->payload.data);
module_put(subtype->owner);
key->type_data.p[0] = NULL;
}
- kfree(key->type_data.p[1]);
- key->type_data.p[1] = NULL;
+
+ if (kids) {
+ kfree(kids->id[0]);
+ kfree(kids->id[1]);
+ kfree(kids);
+ key->type_data.p[1] = NULL;
+ }
}

struct key_type key_type_asymmetric = {
diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c
index 1e9861da7ee4..3bd5a1e4c493 100644
--- a/crypto/asymmetric_keys/pkcs7_parser.c
+++ b/crypto/asymmetric_keys/pkcs7_parser.c
@@ -29,6 +29,10 @@ struct pkcs7_parse_context {
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;
};

/*
@@ -39,6 +43,7 @@ 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);
}
}
@@ -251,10 +256,10 @@ int pkcs7_extract_cert(void *context, size_t hdrlen,
if (IS_ERR(x509))
return PTR_ERR(x509);

- pr_debug("Got cert for %s\n", x509->subject);
- pr_debug("- fingerprint %s\n", x509->fingerprint);
-
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;
@@ -343,8 +348,8 @@ int pkcs7_sig_note_serial(void *context, size_t hdrlen,
const void *value, size_t vlen)
{
struct pkcs7_parse_context *ctx = context;
- ctx->sinfo->raw_serial = value;
- ctx->sinfo->raw_serial_size = vlen;
+ ctx->raw_serial = value;
+ ctx->raw_serial_size = vlen;
return 0;
}

@@ -356,8 +361,8 @@ int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
const void *value, size_t vlen)
{
struct pkcs7_parse_context *ctx = context;
- ctx->sinfo->raw_issuer = value;
- ctx->sinfo->raw_issuer_size = vlen;
+ ctx->raw_issuer = value;
+ ctx->raw_issuer_size = vlen;
return 0;
}

@@ -390,10 +395,21 @@ int pkcs7_note_signed_info(void *context, size_t hdrlen,
const void *value, size_t vlen)
{
struct pkcs7_parse_context *ctx = context;
-
- ctx->sinfo->index = ++ctx->sinfo_index;
- *ctx->ppsinfo = ctx->sinfo;
- ctx->ppsinfo = &ctx->sinfo->next;
+ 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;
diff --git a/crypto/asymmetric_keys/pkcs7_parser.h b/crypto/asymmetric_keys/pkcs7_parser.h
index d25f4d15370f..91949f92bc72 100644
--- a/crypto/asymmetric_keys/pkcs7_parser.h
+++ b/crypto/asymmetric_keys/pkcs7_parser.h
@@ -33,10 +33,7 @@ struct pkcs7_signed_info {
const void *authattrs;

/* Issuing cert serial number and issuer's name */
- const void *raw_serial;
- unsigned raw_serial_size;
- unsigned raw_issuer_size;
- const void *raw_issuer;
+ struct asymmetric_key_id *signing_cert_id;

/* Message signature.
*
diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c
index fad888ea4fad..09197e50fa82 100644
--- a/crypto/asymmetric_keys/pkcs7_trust.c
+++ b/crypto/asymmetric_keys/pkcs7_trust.c
@@ -49,8 +49,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
/* Look to see if this certificate is present in the trusted
* keys.
*/
- key = x509_request_asymmetric_key(trust_keyring, x509->subject,
- x509->fingerprint);
+ key = x509_request_asymmetric_key(trust_keyring, x509->id);
if (!IS_ERR(key))
/* One of the X.509 certificates in the PKCS#7 message
* is apparently the same as one we already trust.
@@ -82,8 +81,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
return -ENOKEY;
}

- key = x509_request_asymmetric_key(trust_keyring, last->issuer,
- last->authority);
+ key = x509_request_asymmetric_key(trust_keyring, last->authority);
if (IS_ERR(key))
return PTR_ERR(key) == -ENOMEM ? -ENOMEM : -ENOKEY;
x509 = last;
diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index c62cf8006e1f..57e90fa17f2b 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -131,8 +131,7 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
struct x509_certificate *x509;
unsigned certix = 1;

- kenter("%u,%u,%u",
- sinfo->index, sinfo->raw_serial_size, sinfo->raw_issuer_size);
+ kenter("%u", sinfo->index);

for (x509 = pkcs7->certs; x509; x509 = x509->next, certix++) {
/* I'm _assuming_ that the generator of the PKCS#7 message will
@@ -140,21 +139,11 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
* PKCS#7 message - but I can't be 100% sure of that. It's
* possible this will need element-by-element comparison.
*/
- if (x509->raw_serial_size != sinfo->raw_serial_size ||
- memcmp(x509->raw_serial, sinfo->raw_serial,
- sinfo->raw_serial_size) != 0)
+ if (!asymmetric_key_id_same(x509->id, sinfo->signing_cert_id))
continue;
pr_devel("Sig %u: Found cert serial match X.509[%u]\n",
sinfo->index, certix);

- if (x509->raw_issuer_size != sinfo->raw_issuer_size ||
- memcmp(x509->raw_issuer, sinfo->raw_issuer,
- sinfo->raw_issuer_size) != 0) {
- pr_warn("Sig %u: X.509 subject and PKCS#7 issuer don't match\n",
- sinfo->index);
- continue;
- }
-
if (x509->pub->pkey_algo != sinfo->sig.pkey_algo) {
pr_warn("Sig %u: X.509 algo and PKCS#7 sig algo don't match\n",
sinfo->index);
@@ -164,8 +153,10 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
sinfo->signer = x509;
return 0;
}
+
pr_warn("Sig %u: Issuing X.509 cert not found (#%*ph)\n",
- sinfo->index, sinfo->raw_serial_size, sinfo->raw_serial);
+ sinfo->index,
+ sinfo->signing_cert_id->len, sinfo->signing_cert_id->data);
return -ENOKEY;
}

@@ -184,7 +175,9 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
p->seen = false;

for (;;) {
- pr_debug("verify %s: %s\n", x509->subject, x509->fingerprint);
+ pr_debug("verify %s: %*phN\n",
+ x509->subject,
+ x509->raw_serial_size, x509->raw_serial);
x509->seen = true;
ret = x509_get_sig_params(x509);
if (ret < 0)
@@ -192,7 +185,8 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,

pr_debug("- issuer %s\n", x509->issuer);
if (x509->authority)
- pr_debug("- authkeyid %s\n", x509->authority);
+ pr_debug("- authkeyid %*phN\n",
+ x509->authority->len, x509->authority->data);

if (!x509->authority ||
strcmp(x509->subject, x509->issuer) == 0) {
@@ -218,13 +212,14 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
/* Look through the X.509 certificates in the PKCS#7 message's
* list to see if the next one is there.
*/
- pr_debug("- want %s\n", x509->authority);
+ pr_debug("- want %*phN\n",
+ x509->authority->len, x509->authority->data);
for (p = pkcs7->certs; p; p = p->next) {
- pr_debug("- cmp [%u] %s\n", p->index, p->fingerprint);
- if (p->raw_subject_size == x509->raw_issuer_size &&
- strcmp(p->fingerprint, x509->authority) == 0 &&
- memcmp(p->raw_subject, x509->raw_issuer,
- x509->raw_issuer_size) == 0)
+ if (!p->skid)
+ continue;
+ pr_debug("- cmp [%u] %*phN\n",
+ p->index, p->skid->len, p->skid->data);
+ if (asymmetric_key_id_same(p->skid, x509->authority))
goto found_issuer;
}

@@ -233,7 +228,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
return 0;

found_issuer:
- pr_debug("- issuer %s\n", p->subject);
+ pr_debug("- subject %s\n", p->subject);
if (p->seen) {
pr_warn("Sig %u: X.509 chain contains loop\n",
sinfo->index);
@@ -304,7 +299,8 @@ int pkcs7_verify(struct pkcs7_message *pkcs7)
ret = x509_get_sig_params(x509);
if (ret < 0)
return ret;
- pr_debug("X.509[%u] %s\n", n, x509->authority);
+ pr_debug("X.509[%u] %*phN\n",
+ n, x509->authority->len, x509->authority->data);
}

for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) {
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index ac72348c186a..96151b2b91a2 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -46,7 +46,8 @@ void x509_free_certificate(struct x509_certificate *cert)
public_key_destroy(cert->pub);
kfree(cert->issuer);
kfree(cert->subject);
- kfree(cert->fingerprint);
+ kfree(cert->id);
+ kfree(cert->skid);
kfree(cert->authority);
kfree(cert->sig.digest);
mpi_free(cert->sig.rsa.s);
@@ -62,6 +63,7 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
{
struct x509_certificate *cert;
struct x509_parse_context *ctx;
+ struct asymmetric_key_id *kid;
long ret;

ret = -ENOMEM;
@@ -89,6 +91,17 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
if (ret < 0)
goto error_decode;

+ /* 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;
+
kfree(ctx);
return cert;

@@ -407,36 +420,34 @@ int x509_process_extension(void *context, size_t hdrlen,
const void *value, size_t vlen)
{
struct x509_parse_context *ctx = context;
+ struct asymmetric_key_id *kid;
const unsigned char *v = value;
- char *f;
int i;

pr_debug("Extension: %u\n", ctx->last_oid);

if (ctx->last_oid == OID_subjectKeyIdentifier) {
/* Get hold of the key fingerprint */
- if (vlen < 3)
+ if (ctx->cert->skid || vlen < 3)
return -EBADMSG;
if (v[0] != ASN1_OTS || v[1] != vlen - 2)
return -EBADMSG;
v += 2;
vlen -= 2;

- f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
- if (!f)
- return -ENOMEM;
- for (i = 0; i < vlen; i++)
- sprintf(f + i * 2, "%02x", v[i]);
- pr_debug("fingerprint %s\n", f);
- ctx->cert->fingerprint = f;
+ kid = asymmetric_key_generate_id(v, vlen,
+ ctx->cert->raw_subject,
+ ctx->cert->raw_subject_size);
+ 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) {
- size_t key_len;
-
/* Get hold of the CA key fingerprint */
- if (vlen < 5)
+ if (ctx->cert->authority || vlen < 5)
return -EBADMSG;

/* Authority Key Identifier must be a Constructed SEQUENCE */
@@ -454,7 +465,7 @@ int x509_process_extension(void *context, size_t hdrlen,
v[3] > vlen - 4)
return -EBADMSG;

- key_len = v[3];
+ vlen = v[3];
v += 4;
} else {
/* Long Form length */
@@ -476,17 +487,17 @@ int x509_process_extension(void *context, size_t hdrlen,
v[sub + 1] > vlen - 4 - sub)
return -EBADMSG;

- key_len = v[sub + 1];
+ vlen = v[sub + 1];
v += (sub + 2);
}

- f = kmalloc(key_len * 2 + 1, GFP_KERNEL);
- if (!f)
- return -ENOMEM;
- for (i = 0; i < key_len; i++)
- sprintf(f + i * 2, "%02x", v[i]);
- pr_debug("authority %s\n", f);
- ctx->cert->authority = f;
+ kid = asymmetric_key_generate_id(v, vlen,
+ ctx->cert->raw_issuer,
+ ctx->cert->raw_issuer_size);
+ if (IS_ERR(kid))
+ return PTR_ERR(kid);
+ pr_debug("authkeyid %*phN\n", kid->len, kid->data);
+ ctx->cert->authority = kid;
return 0;
}

diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h
index 1b76f207c1f3..0e8d59b010fb 100644
--- a/crypto/asymmetric_keys/x509_parser.h
+++ b/crypto/asymmetric_keys/x509_parser.h
@@ -19,8 +19,9 @@ struct x509_certificate {
struct public_key_signature sig; /* Signature parameters */
char *issuer; /* Name of certificate issuer */
char *subject; /* Name of certificate subject */
- char *fingerprint; /* Key fingerprint as hex */
- char *authority; /* Authority key fingerprint as hex */
+ struct asymmetric_key_id *id; /* Issuer + serial number */
+ struct asymmetric_key_id *skid; /* Subject key identifier */
+ struct asymmetric_key_id *authority; /* Authority key identifier */
struct tm valid_from;
struct tm valid_to;
const void *tbs; /* Signed data */
diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
index f3d62307e6ee..c60905c3f4d2 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -25,7 +25,7 @@
#include "x509_parser.h"

static bool use_builtin_keys;
-static char *ca_keyid;
+static struct asymmetric_key_id *ca_keyid;

#ifndef MODULE
static int __init ca_keys_setup(char *str)
@@ -33,10 +33,16 @@ static int __init ca_keys_setup(char *str)
if (!str) /* default system keyring */
return 1;

- if (strncmp(str, "id:", 3) == 0)
- ca_keyid = str; /* owner key 'id:xxxxxx' */
- else if (strcmp(str, "builtin") == 0)
+ if (strncmp(str, "id:", 3) == 0) {
+ struct asymmetric_key_id *p;
+ p = asymmetric_key_hex_to_key_id(str);
+ if (p == ERR_PTR(-EINVAL))
+ pr_err("Unparsable hex string in ca_keys\n");
+ else if (!IS_ERR(p))
+ ca_keyid = p; /* owner key 'id:xxxxxx' */
+ } else if (strcmp(str, "builtin") == 0) {
use_builtin_keys = true;
+ }

return 1;
}
@@ -46,31 +52,28 @@ __setup("ca_keys=", ca_keys_setup);
/**
* x509_request_asymmetric_key - Request a key by X.509 certificate params.
* @keyring: The keys to search.
- * @subject: The name of the subject to whom the key belongs.
- * @key_id: The subject key ID as a hex string.
+ * @kid: The key ID.
*
* Find a key in the given keyring by subject name and key ID. These might,
* for instance, be the issuer name and the authority key ID of an X.509
* certificate that needs to be verified.
*/
struct key *x509_request_asymmetric_key(struct key *keyring,
- const char *subject,
- const char *key_id)
+ const struct asymmetric_key_id *kid)
{
key_ref_t key;
- size_t subject_len = strlen(subject), key_id_len = strlen(key_id);
- char *id;
+ char *id, *p;

- /* Construct an identifier "<subjname>:<keyid>". */
- id = kmalloc(subject_len + 2 + key_id_len + 1, GFP_KERNEL);
+ /* Construct an identifier "id:<keyid>". */
+ p = id = kmalloc(2 + 1 + kid->len * 2 + 1, GFP_KERNEL);
if (!id)
return ERR_PTR(-ENOMEM);

- memcpy(id, subject, subject_len);
- id[subject_len + 0] = ':';
- id[subject_len + 1] = ' ';
- memcpy(id + subject_len + 2, key_id, key_id_len);
- id[subject_len + 2 + key_id_len] = 0;
+ *p++ = 'i';
+ *p++ = 'd';
+ *p++ = ':';
+ p = bin2hex(p, kid->data, kid->len);
+ *p = 0;

pr_debug("Look up: \"%s\"\n", id);

@@ -195,11 +198,10 @@ static int x509_validate_trust(struct x509_certificate *cert,
if (!trust_keyring)
return -EOPNOTSUPP;

- if (ca_keyid && !asymmetric_keyid_match(cert->authority, ca_keyid))
+ if (ca_keyid && !asymmetric_key_id_same(cert->authority, ca_keyid))
return -EPERM;

- key = x509_request_asymmetric_key(trust_keyring,
- cert->issuer, cert->authority);
+ key = x509_request_asymmetric_key(trust_keyring, cert->authority);
if (!IS_ERR(key)) {
if (!use_builtin_keys
|| test_bit(KEY_FLAG_BUILTIN, &key->flags))
@@ -214,9 +216,11 @@ static int x509_validate_trust(struct x509_certificate *cert,
*/
static int x509_key_preparse(struct key_preparsed_payload *prep)
{
+ struct asymmetric_key_ids *kids;
struct x509_certificate *cert;
+ const char *q;
size_t srlen, sulen;
- char *desc = NULL;
+ char *desc = NULL, *p;
int ret;

cert = x509_cert_parse(prep->data, prep->datalen);
@@ -249,19 +253,12 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
pkey_algo_name[cert->sig.pkey_algo],
hash_algo_name[cert->sig.pkey_hash_algo]);

- if (!cert->fingerprint) {
- pr_warn("Cert for '%s' must have a SubjKeyId extension\n",
- cert->subject);
- ret = -EKEYREJECTED;
- goto error_free_cert;
- }
-
cert->pub->algo = pkey_algo[cert->pub->pkey_algo];
cert->pub->id_type = PKEY_ID_X509;

/* Check the signature on the key if it appears to be self-signed */
if (!cert->authority ||
- strcmp(cert->fingerprint, cert->authority) == 0) {
+ asymmetric_key_id_same(cert->skid, cert->authority)) {
ret = x509_check_signature(cert->pub, cert); /* self-signed */
if (ret < 0)
goto error_free_cert;
@@ -273,31 +270,47 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)

/* Propose a description */
sulen = strlen(cert->subject);
- srlen = strlen(cert->fingerprint);
+ srlen = cert->raw_serial_size;
+ q = cert->raw_serial;
+ if (srlen > 1 && *q == 0) {
+ srlen--;
+ q++;
+ }
+
ret = -ENOMEM;
- desc = kmalloc(sulen + 2 + srlen + 1, GFP_KERNEL);
+ desc = kmalloc(sulen + 2 + srlen * 2 + 1, GFP_KERNEL);
if (!desc)
goto error_free_cert;
- memcpy(desc, cert->subject, sulen);
- desc[sulen] = ':';
- desc[sulen + 1] = ' ';
- memcpy(desc + sulen + 2, cert->fingerprint, srlen);
- desc[sulen + 2 + srlen] = 0;
+ p = memcpy(desc, cert->subject, sulen);
+ p += sulen;
+ *p++ = ':';
+ *p++ = ' ';
+ p = bin2hex(p, q, srlen);
+ *p = 0;
+
+ kids = kmalloc(sizeof(struct asymmetric_key_ids), GFP_KERNEL);
+ if (!kids)
+ goto error_free_desc;
+ kids->id[0] = cert->id;
+ kids->id[1] = cert->skid;

/* We're pinning the module by being linked against it */
__module_get(public_key_subtype.owner);
prep->type_data[0] = &public_key_subtype;
- prep->type_data[1] = cert->fingerprint;
+ prep->type_data[1] = kids;
prep->payload[0] = cert->pub;
prep->description = desc;
prep->quotalen = 100;

/* We've finished with the certificate */
cert->pub = NULL;
- cert->fingerprint = NULL;
+ cert->id = NULL;
+ cert->skid = NULL;
desc = NULL;
ret = 0;

+error_free_desc:
+ kfree(desc);
error_free_cert:
x509_free_certificate(cert);
return ret;
diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h
index 0d164c6af539..fa73a6fd536c 100644
--- a/include/crypto/public_key.h
+++ b/include/crypto/public_key.h
@@ -15,6 +15,7 @@
#define _LINUX_PUBLIC_KEY_H

#include <linux/mpi.h>
+#include <keys/asymmetric-type.h>
#include <crypto/hash_info.h>

enum pkey_algo {
@@ -98,8 +99,8 @@ struct key;
extern int verify_signature(const struct key *key,
const struct public_key_signature *sig);

+struct asymmetric_key_id;
extern struct key *x509_request_asymmetric_key(struct key *keyring,
- const char *issuer,
- const char *key_id);
+ const struct asymmetric_key_id *kid);

#endif /* _LINUX_PUBLIC_KEY_H */

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