[PATCH 0/5] RFC v2: AF_ALG auditing

[PATCH 0/5] RFC v2: AF_ALG auditing

[Miloslav Trmač]

Hello,
these patches add support for auditing uses of the AF_ALG protocol family
developed by Herbert Xu to provide user-space access to kernel crypto
accelerators.

One new record is defined: AUDIT_CRYPTO_USERSPACE_OP.  An audited event
is always caused by a syscall, and all other syscall-related data
(process identity, syscall result) is audited in the usual records.

To disable auditing crypto by default and to allow the users to
selectively enable them using filters, a new filter field
AUDIT_CRYPTO_OP is defined; auditing of all crypto operations can
thus be enabled using (auditctl -a exit,always -F crypto_op!=0).

Changes since the previous version:
* Use audit_aux_data instead of a separate linked list
* Don't overwrite initial values of "err" by 0 in algif_skcipher.c
    Mirek

Miloslav Trmač (5):
  Add general crypto auditing infrastructure
  Add unique IDs to AF_ALG sockets
  Add "alg_name" operation to af_alg_type.
  Audit type-independent events
  Audit type-specific crypto operations

 crypto/af_alg.c         |  110 ++++++++++++++++++++++++++++++++++++++++++++++-
 crypto/algif_hash.c     |   35 +++++++++++++--
 crypto/algif_skcipher.c |   28 +++++++++++-
 include/crypto/if_alg.h |   17 +++++--
 include/linux/audit.h   |   22 +++++++++
 kernel/auditfilter.c    |    2 +
 kernel/auditsc.c        |   97 +++++++++++++++++++++++++++++++++++++++++
 7 files changed, 296 insertions(+), 15 deletions(-)

-- 
1.7.3.2

[PATCH 1/5] Add general crypto auditing infrastructure

[Miloslav Trmač]

Collect audited crypto operations in a list, because a single _exit()
can cause several AF_ALG sockets to be closed, and each needs to be
audited.

Add the AUDIT_CRYPTO_OP field so that crypto operations are not audited
by default, but auditing can be enabled using a rule (probably
"-F crypto_op!=0").

Signed-off-by: Miloslav Trmač <mitr@redhat.com>
---
 include/linux/audit.h |   22 +++++++++++
 kernel/auditfilter.c  |    2 +
 kernel/auditsc.c      |   97 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 121 insertions(+), 0 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index f391d45..a9516da 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -122,6 +122,8 @@
 #define AUDIT_MAC_UNLBL_STCADD	1416	/* NetLabel: add a static label */
 #define AUDIT_MAC_UNLBL_STCDEL	1417	/* NetLabel: del a static label */
 
+#define AUDIT_CRYPTO_USERSPACE_OP   1600 /* User-space crypto operation */
+
 #define AUDIT_FIRST_KERN_ANOM_MSG   1700
 #define AUDIT_LAST_KERN_ANOM_MSG    1799
 #define AUDIT_ANOM_PROMISCUOUS      1700 /* Device changed promiscuous mode */
@@ -219,6 +221,7 @@
 #define AUDIT_PERM	106
 #define AUDIT_DIR	107
 #define AUDIT_FILETYPE	108
+#define AUDIT_CRYPTO_OP	109
 
 #define AUDIT_ARG0      200
 #define AUDIT_ARG1      (AUDIT_ARG0+1)
@@ -314,6 +317,13 @@ enum {
 #define AUDIT_PERM_READ		4
 #define AUDIT_PERM_ATTR		8
 
+#define AUDIT_CRYPTO_OP_TFM_NEW		1
+#define AUDIT_CRYPTO_OP_TFM_KEY_IMPORT	2
+#define AUDIT_CRYPTO_OP_TFM_DEL		3
+#define AUDIT_CRYPTO_OP_CTX_NEW		4
+#define AUDIT_CRYPTO_OP_CTX_OP		5
+#define AUDIT_CRYPTO_OP_CTX_DEL		6
+
 struct audit_status {
 	__u32		mask;		/* Bit mask for valid entries */
 	__u32		enabled;	/* 1 = enabled, 0 = disabled */
@@ -478,6 +488,8 @@ extern int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
 				  const struct cred *new,
 				  const struct cred *old);
 extern void __audit_log_capset(pid_t pid, const struct cred *new, const struct cred *old);
+extern int __audit_log_crypto_op(int op, int tfm, int ctx, int ctx2,
+				 const char *algorithm, const char *operation);
 
 static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
@@ -531,6 +543,15 @@ static inline void audit_log_capset(pid_t pid, const struct cred *new,
 		__audit_log_capset(pid, new, old);
 }
 
+static inline int audit_log_crypto_op(int op, int tfm, int ctx, int ctx2,
+				      const char *algorithm,
+				      const char *operation)
+{
+	if (unlikely(!audit_dummy_context()))
+		return __audit_log_crypto_op(op, tfm, ctx, ctx2, algorithm, operation);
+	return 0;
+}
+
 extern int audit_n_rules;
 extern int audit_signals;
 #else
@@ -564,6 +585,7 @@ extern int audit_signals;
 #define audit_mq_getsetattr(d,s) ((void)0)
 #define audit_log_bprm_fcaps(b, ncr, ocr) ({ 0; })
 #define audit_log_capset(pid, ncr, ocr) ((void)0)
+#define audit_log_crypto_op(op, tfm, ctx, ctx2, algorithm, operation) (0)
 #define audit_ptrace(t) ((void)0)
 #define audit_n_rules 0
 #define audit_signals 0
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index ce08041..6f35eed 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -364,6 +364,7 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
 		case AUDIT_DEVMINOR:
 		case AUDIT_EXIT:
 		case AUDIT_SUCCESS:
+		case AUDIT_CRYPTO_OP:
 			/* bit ops are only useful on syscall args */
 			if (f->op == Audit_bitmask || f->op == Audit_bittest)
 				goto exit_free;
@@ -454,6 +455,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 		case AUDIT_DEVMINOR:
 		case AUDIT_EXIT:
 		case AUDIT_SUCCESS:
+		case AUDIT_CRYPTO_OP:
 		case AUDIT_ARG0:
 		case AUDIT_ARG1:
 		case AUDIT_ARG2:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 3828ad5..e9761ad 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -158,6 +158,16 @@ struct audit_aux_data_capset {
 	struct audit_cap_data	cap;
 };
 
+struct audit_aux_data_crypto_op {
+	struct audit_aux_data	d;
+	int			op;
+	int			tfm;
+	int			ctx;	    /* -1 means N/A */
+	int			ctx2;	    /* -1 means N/A */
+	const char		*algorithm; /* NULL means N/A */
+	const char		*operation; /* NULL means N/A */
+};
+
 struct audit_tree_refs {
 	struct audit_tree_refs *next;
 	struct audit_chunk *c[31];
@@ -633,6 +643,24 @@ static int audit_filter_rules(struct task_struct *tsk,
 		case AUDIT_FILETYPE:
 			result = audit_match_filetype(ctx, f->val);
 			break;
+		case AUDIT_CRYPTO_OP: {
+			struct audit_aux_data *aux;
+
+			if (!ctx)
+				break;
+			for (aux = ctx->aux; aux; aux = aux->next) {
+				struct audit_aux_data_crypto_op *ax;
+
+				if (aux->type != AUDIT_CRYPTO_USERSPACE_OP)
+					continue;
+				ax = (void *)aux;
+				result = audit_comparator(ax->op, f->op,
+							  f->val);
+				if (result)
+					break;
+			}
+			break;
+		}
 		}
 
 		if (!result) {
@@ -1201,6 +1229,37 @@ static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *c
 	}
 }
 
+static void log_crypto_op(struct audit_buffer *ab,
+			  const struct audit_aux_data_crypto_op *crypto)
+{
+	static const char *const ops[] = {
+		[AUDIT_CRYPTO_OP_TFM_NEW] = "tfm_new",
+		[AUDIT_CRYPTO_OP_TFM_KEY_IMPORT] = "tfm_key_import",
+		[AUDIT_CRYPTO_OP_TFM_DEL] = "tfm_del",
+		[AUDIT_CRYPTO_OP_CTX_NEW] = "ctx_new",
+		[AUDIT_CRYPTO_OP_CTX_OP] = "ctx_op",
+		[AUDIT_CRYPTO_OP_CTX_DEL] = "ctx_del",
+	};
+
+	if (crypto->op < ARRAY_SIZE(ops) && ops[crypto->op] != NULL)
+		audit_log_format(ab, "crypto_op=%s", ops[crypto->op]);
+	else
+		audit_log_format(ab, "crypto_op=%d", crypto->op);
+	audit_log_format(ab, " tfm=%d", crypto->tfm);
+	if (crypto->ctx != -1)
+		audit_log_format(ab, " ctx=%d", crypto->ctx);
+	if (crypto->ctx2 != -1)
+		audit_log_format(ab, " ctx2=%d", crypto->ctx2);
+	if (crypto->algorithm != NULL) {
+		audit_log_format(ab, " algorithm=");
+		audit_log_string(ab, crypto->algorithm);
+	}
+	if (crypto->operation != NULL) {
+		audit_log_format(ab, " operation=");
+		audit_log_string(ab, crypto->operation);
+	}
+}
+
 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
 {
 	kernel_cap_t *perm = &name->fcap.permitted;
@@ -1404,6 +1463,11 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
 			break; }
 
+		case AUDIT_CRYPTO_USERSPACE_OP: {
+			struct audit_aux_data_crypto_op *axc = (void *)aux;
+			log_crypto_op(ab, axc);
+			break; }
+
 		}
 		audit_log_end(ab);
 	}
@@ -2464,6 +2528,39 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
 }
 
 /**
+ * __audit_log_crypto_op - store information about an user-space crypto op
+ * @op: AUDIT_CRYPTO_OP_*
+ * @tfm: unique transform ID
+ * @ctx: unique context ID, or -1
+ * @ctx2: secondary context ID, or -1
+ * @algorithm: algorithm (crypto API transform) name, or NULL
+ * @operation: more detailed operation description, or NULL
+ */
+int __audit_log_crypto_op(int op, int tfm, int ctx, int ctx2,
+			  const char *algorithm, const char *operation)
+{
+	struct audit_aux_data_crypto_op *ax;
+	struct audit_context *context = current->audit_context;
+
+	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
+	if (!ax)
+		return -ENOMEM;
+
+	ax->d.type = AUDIT_CRYPTO_USERSPACE_OP;
+	ax->d.next = context->aux;
+	context->aux = (void *)ax;
+
+	ax->op = op;
+	ax->tfm = tfm;
+	ax->ctx = ctx;
+	ax->ctx2 = ctx2;
+	ax->algorithm = algorithm;
+	ax->operation = operation;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__audit_log_crypto_op);
+
+/**
  * __audit_log_capset - store information about the arguments to the capset syscall
  * @pid: target pid of the capset call
  * @new: the new credentials
-- 
1.7.3.2

[PATCH 2/5] Add unique IDs to AF_ALG sockets

[Miloslav Trmač]

Ideally we should be able to use i_ino of the inode associated with the
socket, but i_ino can have duplicate values if the static counter inside
new_inode() wraps around.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>
---
 crypto/af_alg.c         |   66 +++++++++++++++++++++++++++++++++++++++++++++-
 crypto/algif_hash.c     |    2 +-
 crypto/algif_skcipher.c |    2 +-
 include/crypto/if_alg.h |   10 +++---
 4 files changed, 71 insertions(+), 9 deletions(-)

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index cabed0e..490ae43 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -15,10 +15,12 @@
 #include <asm/atomic.h>
 #include <crypto/if_alg.h>
 #include <linux/crypto.h>
+#include <linux/idr.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 #include <linux/net.h>
 #include <linux/rwsem.h>
 
@@ -38,6 +40,10 @@ static struct proto alg_proto = {
 
 static LIST_HEAD(alg_types);
 static DECLARE_RWSEM(alg_types_sem);
+#ifdef CONFIG_AUDIT
+static DEFINE_MUTEX(alg_ida_mutex);
+static DEFINE_IDA(alg_ida);
+#endif
 
 static const struct af_alg_type *alg_get_type(const char *name)
 {
@@ -107,6 +113,59 @@ int af_alg_unregister_type(const struct af_alg_type *type)
 }
 EXPORT_SYMBOL_GPL(af_alg_unregister_type);
 
+static struct sock *alg_sk_alloc(struct net *net)
+{
+	struct sock *sk;
+
+	sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto);
+	if (!sk)
+		goto out;
+
+#ifdef CONFIG_AUDIT
+	mutex_lock(&alg_ida_mutex);
+	/* ida_pre_get() should preallocate enough, and, due to
+	   lists_ida_mutex, nobody else can use the preallocated data.
+	   Therefore the loop recommended in idr_get_new() documentation is not
+	   necessary. */
+	if (ida_pre_get(&alg_ida, GFP_KERNEL) == 0 ||
+	    ida_get_new(&alg_ida, &alg_sk(sk)->id) != 0) {
+		mutex_unlock(&alg_ida_mutex);
+		alg_sk(sk)->id = -1;
+		sk_free(sk);
+		sk = NULL;
+		goto out;
+	}
+	mutex_unlock(&alg_ida_mutex);
+#endif
+
+out:
+	return sk;
+}
+
+#ifdef CONFIG_AUDIT
+static void alg_sk_destruct(struct sock *sk)
+{
+	struct alg_sock *ask = alg_sk(sk);
+
+	if (ask->id != -1) {
+               mutex_lock(&alg_ida_mutex);
+               ida_remove(&alg_ida, ask->id);
+               mutex_unlock(&alg_ida_mutex);
+	}
+}
+#else
+static void alg_sk_destruct(struct sock *sk) {}
+#endif
+
+void af_alg_sk_destruct_child(struct sock *sk)
+{
+	struct alg_sock *ask = alg_sk(sk);
+
+	sock_put(ask->parent);
+	alg_sk_destruct(sk);
+}
+EXPORT_SYMBOL_GPL(af_alg_sk_destruct_child);
+
 static void alg_do_release(const struct af_alg_type *type, void *private)
 {
 	if (!type)
@@ -236,7 +295,7 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
 	if (!type)
 		goto unlock;
 
-	sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto);
+	sk2 = alg_sk_alloc(sock_net(sk));
 	err = -ENOMEM;
 	if (!sk2)
 		goto unlock;
@@ -245,6 +304,7 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
 
 	err = type->accept(ask->private, sk2);
 	if (err) {
+		alg_sk_destruct(sk2);
 		sk_free(sk2);
 		goto unlock;
 	}
@@ -300,6 +360,7 @@ static void alg_sock_destruct(struct sock *sk)
 	struct alg_sock *ask = alg_sk(sk);
 
 	alg_do_release(ask->type, ask->private);
+	alg_sk_destruct(sk);
 }
 
 static int alg_create(struct net *net, struct socket *sock, int protocol,
@@ -314,7 +375,7 @@ static int alg_create(struct net *net, struct socket *sock, int protocol,
 		return -EPROTONOSUPPORT;
 
 	err = -ENOMEM;
-	sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto);
+	sk = alg_sk_alloc(net);
 	if (!sk)
 		goto out;
 
@@ -474,6 +535,7 @@ static void __exit af_alg_exit(void)
 {
 	sock_unregister(PF_ALG);
 	proto_unregister(&alg_proto);
+	ida_destroy(&alg_ida);
 }
 
 module_init(af_alg_init);
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index 62122a1..f08a42c 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -256,7 +256,7 @@ static void hash_sock_destruct(struct sock *sk)
 	sock_kfree_s(sk, ctx->result,
 		     crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
 	sock_kfree_s(sk, ctx, ctx->len);
-	af_alg_release_parent(sk);
+	af_alg_sk_destruct_child(sk);
 }
 
 static int hash_accept_parent(void *private, struct sock *sk)
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index d8d3ddf..4069460 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -575,7 +575,7 @@ static void skcipher_sock_destruct(struct sock *sk)
 	skcipher_free_sgl(sk);
 	sock_kfree_s(sk, ctx->iv, crypto_ablkcipher_ivsize(tfm));
 	sock_kfree_s(sk, ctx, ctx->len);
-	af_alg_release_parent(sk);
+	af_alg_sk_destruct_child(sk);
 }
 
 static int skcipher_accept_parent(void *private, struct sock *sk)
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index c5813c8..336b9f2 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -31,6 +31,9 @@ struct alg_sock {
 
 	const struct af_alg_type *type;
 	void *private;
+#ifdef CONFIG_AUDIT
+	int id;
+#endif
 };
 
 struct af_alg_completion {
@@ -62,6 +65,8 @@ struct af_alg_sgl {
 int af_alg_register_type(const struct af_alg_type *type);
 int af_alg_unregister_type(const struct af_alg_type *type);
 
+void af_alg_sk_destruct_child(struct sock *sk);
+
 int af_alg_release(struct socket *sock);
 int af_alg_accept(struct sock *sk, struct socket *newsock);
 
@@ -79,11 +84,6 @@ static inline struct alg_sock *alg_sk(struct sock *sk)
 	return (struct alg_sock *)sk;
 }
 
-static inline void af_alg_release_parent(struct sock *sk)
-{
-	sock_put(alg_sk(sk)->parent);
-}
-
 static inline void af_alg_init_completion(struct af_alg_completion *completion)
 {
 	init_completion(&completion->completion);
-- 
1.7.3.2

[PATCH 3/5] Add "alg_name" operation to af_alg_type.

[Miloslav Trmač]

Signed-off-by: Miloslav Trmač <mitr@redhat.com>
---
 crypto/algif_hash.c     |    6 ++++++
 crypto/algif_skcipher.c |    6 ++++++
 include/crypto/if_alg.h |    1 +
 3 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index f08a42c..3a61e9d 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -243,6 +243,11 @@ static void hash_release(void *private)
 	crypto_free_ahash(private);
 }
 
+static const char *hash_alg_name(void *private)
+{
+	return crypto_tfm_alg_name(crypto_ahash_tfm(private));
+}
+
 static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
 {
 	return crypto_ahash_setkey(private, key, keylen);
@@ -296,6 +301,7 @@ static int hash_accept_parent(void *private, struct sock *sk)
 static const struct af_alg_type algif_type_hash = {
 	.bind		=	hash_bind,
 	.release	=	hash_release,
+	.alg_name	=	hash_alg_name,
 	.setkey		=	hash_setkey,
 	.accept		=	hash_accept_parent,
 	.ops		=	&algif_hash_ops,
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 4069460..e14c8be 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -561,6 +561,11 @@ static void skcipher_release(void *private)
 	crypto_free_ablkcipher(private);
 }
 
+static const char *skcipher_alg_name(void *private)
+{
+	return crypto_tfm_alg_name(crypto_ablkcipher_tfm(private));
+}
+
 static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
 {
 	return crypto_ablkcipher_setkey(private, key, keylen);
@@ -619,6 +624,7 @@ static int skcipher_accept_parent(void *private, struct sock *sk)
 static const struct af_alg_type algif_type_skcipher = {
 	.bind		=	skcipher_bind,
 	.release	=	skcipher_release,
+	.alg_name	=	skcipher_alg_name,
 	.setkey		=	skcipher_setkey,
 	.accept		=	skcipher_accept_parent,
 	.ops		=	&algif_skcipher_ops,
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 336b9f2..092c599 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -49,6 +49,7 @@ struct af_alg_control {
 struct af_alg_type {
 	void *(*bind)(const char *name, u32 type, u32 mask);
 	void (*release)(void *private);
+	const char *(*alg_name)(void *private);
 	int (*setkey)(void *private, const u8 *key, unsigned int keylen);
 	int (*accept)(void *private, struct sock *sk);
 
-- 
1.7.3.2

[PATCH 4/5] Audit type-independent events

[Miloslav Trmač]

Signed-off-by: Miloslav Trmač <mitr@redhat.com>
---
 crypto/af_alg.c |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 490ae43..fc1b0f7 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -14,6 +14,7 @@
 
 #include <asm/atomic.h>
 #include <crypto/if_alg.h>
+#include <linux/audit.h>
 #include <linux/crypto.h>
 #include <linux/idr.h>
 #include <linux/init.h>
@@ -160,6 +161,11 @@ static void alg_sk_destruct(struct sock *sk) {}
 void af_alg_sk_destruct_child(struct sock *sk)
 {
 	struct alg_sock *ask = alg_sk(sk);
+	struct alg_sock *parent_ask = alg_sk(ask->parent);
+
+	audit_log_crypto_op(AUDIT_CRYPTO_OP_CTX_DEL, parent_ask->id,
+			    ask->id, -1,
+			    ask->type->alg_name(parent_ask->private), NULL);
 
 	sock_put(ask->parent);
 	alg_sk_destruct(sk);
@@ -235,6 +241,11 @@ static int alg_setkey(struct sock *sk, char __user *ukey,
 	u8 *key;
 	int err;
 
+	err = audit_log_crypto_op(AUDIT_CRYPTO_OP_TFM_KEY_IMPORT, ask->id, -1,
+				  -1, type->alg_name(ask->private), NULL);
+	if (err)
+		return err;
+
 	key = sock_kmalloc(sk, keylen, GFP_KERNEL);
 	if (!key)
 		return -ENOMEM;
@@ -315,6 +326,14 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
 	alg_sk(sk2)->parent = sk;
 	alg_sk(sk2)->type = type;
 
+	err = audit_log_crypto_op(AUDIT_CRYPTO_OP_CTX_NEW, ask->id,
+				  alg_sk(sk2)->id, -1,
+				  type->alg_name(ask->private), NULL);
+	if (err) {
+		sk_free(sk2);
+		return err;
+	}
+
 	newsock->ops = type->ops;
 	newsock->state = SS_CONNECTED;
 
@@ -359,6 +378,9 @@ static void alg_sock_destruct(struct sock *sk)
 {
 	struct alg_sock *ask = alg_sk(sk);
 
+	audit_log_crypto_op(AUDIT_CRYPTO_OP_TFM_DEL, ask->id, -1, -1, NULL,
+			    NULL);
+
 	alg_do_release(ask->type, ask->private);
 	alg_sk_destruct(sk);
 }
@@ -379,6 +401,14 @@ static int alg_create(struct net *net, struct socket *sock, int protocol,
 	if (!sk)
 		goto out;
 
+	err = audit_log_crypto_op(AUDIT_CRYPTO_OP_TFM_NEW, alg_sk(sk)->id, -1,
+				  -1, NULL, NULL);
+	if (err) {
+		alg_sk_destruct(sk);
+		sk_free(sk);
+		goto out;
+	}
+
 	sock->ops = &alg_proto_ops;
 	sock_init_data(sock, sk);
 
-- 
1.7.3.2

[PATCH 5/5] Audit type-specific crypto operations

[Miloslav Trmač]

Signed-off-by: Miloslav Trmač <mitr@redhat.com>
---
 crypto/af_alg.c         |   14 ++++++++++++++
 crypto/algif_hash.c     |   27 +++++++++++++++++++++++----
 crypto/algif_skcipher.c |   20 ++++++++++++++++++--
 include/crypto/if_alg.h |    6 ++++++
 4 files changed, 61 insertions(+), 6 deletions(-)

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index fc1b0f7..450d51a 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -542,6 +542,20 @@ void af_alg_complete(struct crypto_async_request *req, int err)
 }
 EXPORT_SYMBOL_GPL(af_alg_complete);
 
+#ifdef CONFIG_AUDIT
+int af_alg_audit_crypto_op(struct sock *sk, const char *operation, int ctx2)
+{
+	struct alg_sock *ask = alg_sk(sk);
+	struct alg_sock *parent_ask = alg_sk(ask->parent);
+	const char *alg_name;
+
+	alg_name = parent_ask->type->alg_name(parent_ask->private);
+	return audit_log_crypto_op(AUDIT_CRYPTO_OP_CTX_OP, parent_ask->id,
+				   ask->id, ctx2, alg_name, operation);
+}
+EXPORT_SYMBOL_GPL(af_alg_audit_crypto_op);
+#endif
+
 static int __init af_alg_init(void)
 {
 	int err = proto_register(&alg_proto, 0);
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index 3a61e9d..7e3ffd1 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -46,6 +46,10 @@ static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
 	long copied = 0;
 	int err;
 
+	err = af_alg_audit_crypto_op(sk, "hash-input", -1);
+	if (err)
+		return err;
+
 	if (limit > sk->sk_sndbuf)
 		limit = sk->sk_sndbuf;
 
@@ -112,6 +116,10 @@ static ssize_t hash_sendpage(struct socket *sock, struct page *page,
 	struct hash_ctx *ctx = ask->private;
 	int err;
 
+	err = af_alg_audit_crypto_op(sk, "hash-input", -1);
+	if (err)
+		return err;
+
 	lock_sock(sk);
 	sg_init_table(ctx->sgl.sg, 1);
 	sg_set_page(ctx->sgl.sg, page, size, offset);
@@ -154,6 +162,10 @@ static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
 	unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
 	int err;
 
+	err = af_alg_audit_crypto_op(sk, "hash-output", -1);
+	if (err)
+		return err;
+
 	if (len > ds)
 		len = ds;
 	else if (len < ds)
@@ -202,12 +214,19 @@ static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
 	ctx2 = ask2->private;
 	ctx2->more = 1;
 
+	err = af_alg_audit_crypto_op(sk, "hash-clone", ask2->id);
+	if (err)
+		goto error_sk2;
+
 	err = crypto_ahash_import(&ctx2->req, state);
-	if (err) {
-		sock_orphan(sk2);
-		sock_put(sk2);
-	}
+	if (err)
+		goto error_sk2;
+
+	return err;
 
+error_sk2:
+	sock_orphan(sk2);
+	sock_put(sk2);
 	return err;
 }
 
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index e14c8be..c5c37d6 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -283,6 +283,11 @@ static int skcipher_sendmsg(struct kiocb *unused, struct socket *sock,
 			memcpy(ctx->iv, con.iv->iv, ivsize);
 	}
 
+	err = af_alg_audit_crypto_op(sk, ctx->enc ? "encrypt-input"
+				     : "decrypt-input", -1);
+	if (err)
+		goto unlock;
+
 	limit = max_t(int, sk->sk_sndbuf, PAGE_SIZE);
 	limit -= ctx->used;
 
@@ -381,9 +386,15 @@ static ssize_t skcipher_sendpage(struct socket *sock, struct page *page,
 	struct alg_sock *ask = alg_sk(sk);
 	struct skcipher_ctx *ctx = ask->private;
 	struct skcipher_sg_list *sgl;
-	int err = -EINVAL;
+	int err;
 	int limit;
 
+	err = af_alg_audit_crypto_op(sk, ctx->enc ? "encrypt-input"
+				     : "decrypt-input", -1);
+	if (err)
+		return err;
+
+	err = -EINVAL;
 	lock_sock(sk);
 	if (!ctx->more && ctx->used)
 		goto unlock;
@@ -439,10 +450,15 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
 	struct scatterlist *sg;
 	unsigned long iovlen;
 	struct iovec *iov;
-	int err = -EAGAIN;
+	int err;
 	int used;
 	long copied = 0;
 
+	err = af_alg_audit_crypto_op(sk, ctx->enc ? "encrypt-output"
+				     : "decrypt-output", -1);
+	if (err)
+		return err;
+
 	lock_sock(sk);
 	for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
 	     iovlen--, iov++) {
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 092c599..6650ae5 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -80,6 +80,12 @@ int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);
 int af_alg_wait_for_completion(int err, struct af_alg_completion *completion);
 void af_alg_complete(struct crypto_async_request *req, int err);
 
+#ifdef CONFIG_AUDIT
+int af_alg_audit_crypto_op(struct sock *sk, const char *operation, int ctx2);
+#else
+#define af_alg_audit_crypto_op(sk, operation, ctx2) (0)
+#endif
+
 static inline struct alg_sock *alg_sk(struct sock *sk)
 {
 	return (struct alg_sock *)sk;
-- 
1.7.3.2

Re: [PATCH 0/5] RFC v2: AF_ALG auditing

[Herbert Xu]

On Wed, Nov 24, 2010 at 06:05:50PM +0100, Miloslav Trmač wrote:
> 
> Miloslav Trmač (5):
>   Add general crypto auditing infrastructure
>   Add unique IDs to AF_ALG sockets
>   Add "alg_name" operation to af_alg_type.
>   Audit type-independent events
>   Audit type-specific crypto operations

Acked-by: Herbert Xu <herbert@gondor.apana.org.au>

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt