Merge tag 'keys-pkcs7-20140916' into keys-next

Changes for next to improve the matching of asymmetric keys and to improve the
handling of PKCS#7 certificates:

 (1) Provide a method to preparse the data supplied for matching a key.  This
     permits they key type to extract out the bits it needs for matching once
     only.

     Further, the type of search (direct lookup or iterative) can be set and
     the function used to actually check the match can be set by preparse
     rather than being hard coded for the type.

 (2) Improves asymmetric keys identification.

     Keys derived from X.509 certs now get labelled with IDs derived from their
     issuer and certificate number (required to match PKCS#7) and from their
     SKID and subject (required to match X.509).

     IDs are now binary and match criterion preparsing is provided so that
     criteria can be turned into binary blobs to make matching faster.

 (3) Improves PKCS#7 message handling to permit PKCS#7 messages without X.509
     cert lists to be matched to trusted keys, thereby allowing minimally sized
     PKCS#7 certs to be used.

 (4) Improves PKCS#7 message handling to better handle certificate chains that
     are broken due to unsupported crypto that can otherwise by used to
     intersect a trust keyring.

These must go on top of the PKCS#7 parser cleanup fixes.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 27 insertions, 11 deletions

diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c
index 1e9861da..3bd5a1e4 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;