PKCS#7: Refactor verify_pkcs7_signature()

IMA will need to verify a PKCS#7 signature which has already been parsed.
For this reason, factor out the code which does that from
verify_pkcs7_signature() into a new function which takes a struct
pkcs7_message instead of a data buffer.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This commit is contained in:
Thiago Jung Bauermann 2019-06-27 23:19:25 -03:00 committed by Mimi Zohar
parent c8424e776b
commit 2a7bf67118
2 changed files with 55 additions and 16 deletions

View File

@ -190,19 +190,18 @@ late_initcall(load_system_certificate_list);
#ifdef CONFIG_SYSTEM_DATA_VERIFICATION #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
/** /**
* verify_pkcs7_signature - Verify a PKCS#7-based signature on system data. * verify_pkcs7_message_sig - Verify a PKCS#7-based signature on system data.
* @data: The data to be verified (NULL if expecting internal data). * @data: The data to be verified (NULL if expecting internal data).
* @len: Size of @data. * @len: Size of @data.
* @raw_pkcs7: The PKCS#7 message that is the signature. * @pkcs7: The PKCS#7 message that is the signature.
* @pkcs7_len: The size of @raw_pkcs7.
* @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only,
* (void *)1UL for all trusted keys). * (void *)1UL for all trusted keys).
* @usage: The use to which the key is being put. * @usage: The use to which the key is being put.
* @view_content: Callback to gain access to content. * @view_content: Callback to gain access to content.
* @ctx: Context for callback. * @ctx: Context for callback.
*/ */
int verify_pkcs7_signature(const void *data, size_t len, int verify_pkcs7_message_sig(const void *data, size_t len,
const void *raw_pkcs7, size_t pkcs7_len, struct pkcs7_message *pkcs7,
struct key *trusted_keys, struct key *trusted_keys,
enum key_being_used_for usage, enum key_being_used_for usage,
int (*view_content)(void *ctx, int (*view_content)(void *ctx,
@ -210,13 +209,8 @@ int verify_pkcs7_signature(const void *data, size_t len,
size_t asn1hdrlen), size_t asn1hdrlen),
void *ctx) void *ctx)
{ {
struct pkcs7_message *pkcs7;
int ret; int ret;
pkcs7 = pkcs7_parse_message(raw_pkcs7, pkcs7_len);
if (IS_ERR(pkcs7))
return PTR_ERR(pkcs7);
/* The data should be detached - so we need to supply it. */ /* The data should be detached - so we need to supply it. */
if (data && pkcs7_supply_detached_data(pkcs7, data, len) < 0) { if (data && pkcs7_supply_detached_data(pkcs7, data, len) < 0) {
pr_err("PKCS#7 signature with non-detached data\n"); pr_err("PKCS#7 signature with non-detached data\n");
@ -269,6 +263,41 @@ int verify_pkcs7_signature(const void *data, size_t len,
} }
error: error:
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
/**
* verify_pkcs7_signature - Verify a PKCS#7-based signature on system data.
* @data: The data to be verified (NULL if expecting internal data).
* @len: Size of @data.
* @raw_pkcs7: The PKCS#7 message that is the signature.
* @pkcs7_len: The size of @raw_pkcs7.
* @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only,
* (void *)1UL for all trusted keys).
* @usage: The use to which the key is being put.
* @view_content: Callback to gain access to content.
* @ctx: Context for callback.
*/
int verify_pkcs7_signature(const void *data, size_t len,
const void *raw_pkcs7, size_t pkcs7_len,
struct key *trusted_keys,
enum key_being_used_for usage,
int (*view_content)(void *ctx,
const void *data, size_t len,
size_t asn1hdrlen),
void *ctx)
{
struct pkcs7_message *pkcs7;
int ret;
pkcs7 = pkcs7_parse_message(raw_pkcs7, pkcs7_len);
if (IS_ERR(pkcs7))
return PTR_ERR(pkcs7);
ret = verify_pkcs7_message_sig(data, len, pkcs7, trusted_keys, usage,
view_content, ctx);
pkcs7_free_message(pkcs7); pkcs7_free_message(pkcs7);
pr_devel("<==%s() = %d\n", __func__, ret); pr_devel("<==%s() = %d\n", __func__, ret);
return ret; return ret;

View File

@ -32,6 +32,7 @@ extern const char *const key_being_used_for[NR__KEY_BEING_USED_FOR];
#ifdef CONFIG_SYSTEM_DATA_VERIFICATION #ifdef CONFIG_SYSTEM_DATA_VERIFICATION
struct key; struct key;
struct pkcs7_message;
extern int verify_pkcs7_signature(const void *data, size_t len, extern int verify_pkcs7_signature(const void *data, size_t len,
const void *raw_pkcs7, size_t pkcs7_len, const void *raw_pkcs7, size_t pkcs7_len,
@ -41,6 +42,15 @@ extern int verify_pkcs7_signature(const void *data, size_t len,
const void *data, size_t len, const void *data, size_t len,
size_t asn1hdrlen), size_t asn1hdrlen),
void *ctx); void *ctx);
extern int verify_pkcs7_message_sig(const void *data, size_t len,
struct pkcs7_message *pkcs7,
struct key *trusted_keys,
enum key_being_used_for usage,
int (*view_content)(void *ctx,
const void *data,
size_t len,
size_t asn1hdrlen),
void *ctx);
#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
extern int verify_pefile_signature(const void *pebuf, unsigned pelen, extern int verify_pefile_signature(const void *pebuf, unsigned pelen,