The getsockopt SO_PEERSEC provides the LSM based security
information for a single module, but for reasons of backward
compatibility cannot include the information for multiple
modules. A new option SO_PEERCONTEXT is added to report the
security "context" of multiple modules using a "compound" format
lsm1\0value\0lsm2\0value\0
This is expected to be used by system services, including dbus-daemon.
Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
---
arch/alpha/include/uapi/asm/socket.h | 1 +
arch/mips/include/uapi/asm/socket.h | 1 +
arch/parisc/include/uapi/asm/socket.h | 1 +
arch/sparc/include/uapi/asm/socket.h | 1 +
include/linux/lsm_hooks.h | 9 ++-
include/linux/security.h | 10 ++-
include/uapi/asm-generic/socket.h | 1 +
net/core/sock.c | 7 +-
security/apparmor/lsm.c | 20 ++----
security/security.c | 94 ++++++++++++++++++++++++---
security/selinux/hooks.c | 20 ++----
security/smack/smack_lsm.c | 31 ++++-----
12 files changed, 134 insertions(+), 62 deletions(-)
diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h
index 976e89b116e5..019e5fa8bcda 100644
--- a/arch/alpha/include/uapi/asm/socket.h
+++ b/arch/alpha/include/uapi/asm/socket.h
@@ -121,6 +121,7 @@
#define SO_RCVTIMEO_NEW 66
#define SO_SNDTIMEO_NEW 67
+#define SO_PEERCONTEXT 68
#if !defined(__KERNEL__)
diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h
index d41765cfbc6e..df8d984d76ed 100644
--- a/arch/mips/include/uapi/asm/socket.h
+++ b/arch/mips/include/uapi/asm/socket.h
@@ -132,6 +132,7 @@
#define SO_RCVTIMEO_NEW 66
#define SO_SNDTIMEO_NEW 67
+#define SO_PEERCONTEXT 68
#if !defined(__KERNEL__)
diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h
index 66c5dd245ac7..9ae358309f46 100644
--- a/arch/parisc/include/uapi/asm/socket.h
+++ b/arch/parisc/include/uapi/asm/socket.h
@@ -113,6 +113,7 @@
#define SO_RCVTIMEO_NEW 0x4040
#define SO_SNDTIMEO_NEW 0x4041
+#define SO_PEERCONTEXT 0x4042
#if !defined(__KERNEL__)
diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h
index 9265a9eece15..e8a53ef65210 100644
--- a/arch/sparc/include/uapi/asm/socket.h
+++ b/arch/sparc/include/uapi/asm/socket.h
@@ -114,6 +114,7 @@
#define SO_RCVTIMEO_NEW 0x0044
#define SO_SNDTIMEO_NEW 0x0045
+#define SO_PEERCONTEXT 0x0046
#if !defined(__KERNEL__)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 33e5ab4af9f8..b0f788bf82b6 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -864,8 +864,8 @@
* SO_GETPEERSEC. For tcp sockets this can be meaningful if the
* socket is associated with an ipsec SA.
* @sock is the local socket.
- * @optval userspace memory where the security state is to be copied.
- * @optlen userspace int where the module should copy the actual length
+ * @optval memory where the security state is to be copied.
+ * @optlen int where the module should copy the actual length
* of the security state.
* @len as input is the maximum length to copy to userspace provided
* by the caller.
@@ -1697,9 +1697,8 @@ union security_list_options {
int (*socket_setsockopt)(struct socket *sock, int level, int optname);
int (*socket_shutdown)(struct socket *sock, int how);
int (*socket_sock_rcv_skb)(struct sock *sk, struct sk_buff *skb);
- int (*socket_getpeersec_stream)(struct socket *sock,
- char __user *optval,
- int __user *optlen, unsigned len);
+ int (*socket_getpeersec_stream)(struct socket *sock, char **optval,
+ int *optlen, unsigned len);
int (*socket_getpeersec_dgram)(struct socket *sock,
struct sk_buff *skb, u32 *secid);
int (*sk_alloc_security)(struct sock *sk, int family, gfp_t priority);
diff --git a/include/linux/security.h b/include/linux/security.h
index 12f6d5fcbf6a..0665a27a2891 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -130,6 +130,7 @@ struct lsmblob {
#define LSMBLOB_NOT_NEEDED -3 /* Slot not requested */
#define LSMBLOB_DISPLAY -4 /* Use the "display" slot */
#define LSMBLOB_FIRST -5 /* Use the default "display" slot */
+#define LSMBLOB_COMPOUND -6 /* A compound "display" */
/**
* lsmblob_init - initialize an lsmblob structure.
@@ -1324,7 +1325,8 @@ int security_socket_setsockopt(struct socket *sock, int level, int optname);
int security_socket_shutdown(struct socket *sock, int how);
int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
- int __user *optlen, unsigned len);
+ int __user *optlen, unsigned len,
+ int display);
int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
struct lsmblob *blob);
int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
@@ -1458,8 +1460,10 @@ static inline int security_sock_rcv_skb(struct sock *sk,
return 0;
}
-static inline int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
- int __user *optlen, unsigned len)
+static inline int security_socket_getpeersec_stream(struct socket *sock,
+ char __user *optval,
+ int __user *optlen,
+ unsigned len, int display)
{
return -ENOPROTOOPT;
}
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 8c1391c89171..b38d080c2802 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -116,6 +116,7 @@
#define SO_RCVTIMEO_NEW 66
#define SO_SNDTIMEO_NEW 67
+#define SO_PEERCONTEXT 68
#if !defined(__KERNEL__)
diff --git a/net/core/sock.c b/net/core/sock.c
index 782343bb925b..b0955a34167c 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1412,7 +1412,12 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
break;
case SO_PEERSEC:
- return security_socket_getpeersec_stream(sock, optval, optlen, len);
+ return security_socket_getpeersec_stream(sock, optval, optlen,
+ len, LSMBLOB_DISPLAY);
+
+ case SO_PEERCONTEXT:
+ return security_socket_getpeersec_stream(sock, optval, optlen,
+ len, LSMBLOB_COMPOUND);
case SO_MARK:
v.val = sk->sk_mark;
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index ec2e39aa9a84..5d25959610f9 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1037,10 +1037,8 @@ static struct aa_label *sk_peer_label(struct sock *sk)
*
* Note: for tcp only valid if using ipsec or cipso on lan
*/
-static int apparmor_socket_getpeersec_stream(struct socket *sock,
- char __user *optval,
- int __user *optlen,
- unsigned int len)
+static int apparmor_socket_getpeersec_stream(struct socket *sock, char **optval,
+ int *optlen, unsigned int len)
{
char *name;
int slen, error = 0;
@@ -1060,17 +1058,11 @@ static int apparmor_socket_getpeersec_stream(struct socket *sock,
if (slen < 0) {
error = -ENOMEM;
} else {
- if (slen > len) {
+ if (slen > len)
error = -ERANGE;
- } else if (copy_to_user(optval, name, slen)) {
- error = -EFAULT;
- goto out;
- }
- if (put_user(slen, optlen))
- error = -EFAULT;
-out:
- kfree(name);
-
+ else
+ *optval = name;
+ *optlen = slen;
}
done:
diff --git a/security/security.c b/security/security.c
index 9e5e3ebd169d..5551c146c035 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2126,8 +2126,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
continue;
- if (lsm == NULL && *display != LSMBLOB_INVALID &&
- *display != hp->lsmid->slot)
+ if (lsm == NULL && display != NULL &&
+ *display != LSMBLOB_INVALID && *display != hp->lsmid->slot)
continue;
return hp->hook.setprocattr(name, value, size);
}
@@ -2351,17 +2351,91 @@ int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
EXPORT_SYMBOL(security_sock_rcv_skb);
int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
- int __user *optlen, unsigned len)
+ int __user *optlen, unsigned len,
+ int display)
{
- int display = lsm_task_display(current);
struct security_hook_list *hp;
+ char *final = NULL;
+ char *cp;
+ char *tp;
+ int rc = 0;
+ unsigned finallen = 0;
+ unsigned llen;
+ unsigned clen = 0;
+ unsigned tlen;
+
+ switch (display) {
+ case LSMBLOB_DISPLAY:
+ rc = -ENOPROTOOPT;
+ display = lsm_task_display(current);
+ hlist_for_each_entry(hp,
+ &security_hook_heads.socket_getpeersec_stream,
+ list)
+ if (display == LSMBLOB_INVALID ||
+ display == hp->lsmid->slot) {
+ rc = hp->hook.socket_getpeersec_stream(sock,
+ &final, &finallen, len);
+ break;
+ }
+ break;
+ case LSMBLOB_COMPOUND:
+ /*
+ * A compound context, in the form lsm='value'[,lsm='value']...
+ */
+ hlist_for_each_entry(hp,
+ &security_hook_heads.socket_getpeersec_stream,
+ list) {
+ rc = hp->hook.socket_getpeersec_stream(sock, &cp, &clen,
+ len);
+ if (rc == -EINVAL || rc == -ENOPROTOOPT) {
+ rc = 0;
+ continue;
+ }
+ if (rc) {
+ kfree(final);
+ return rc;
+ }
+ /*
+ * Don't propogate trailing nul bytes.
+ */
+ clen = strnlen(cp, clen) + 1;
+ llen = strlen(hp->lsmid->lsm) + 1;
+ tlen = llen + clen;
+ if (final)
+ tlen += finallen;
+ tp = kzalloc(tlen, GFP_KERNEL);
+ if (tp == NULL) {
+ kfree(cp);
+ kfree(final);
+ return -ENOMEM;
+ }
+ if (final)
+ memcpy(tp, final, finallen);
+ memcpy(tp + finallen, hp->lsmid->lsm, llen);
+ memcpy(tp + finallen + llen, cp, clen);
+ kfree(cp);
+ if (final)
+ kfree(final);
+ final = tp;
+ finallen = tlen;
+ }
+ if (final == NULL)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
- hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
- list)
- if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
- return hp->hook.socket_getpeersec_stream(sock, optval,
- optlen, len);
- return -ENOPROTOOPT;
+ if (finallen > len)
+ rc = -ERANGE;
+ else if (copy_to_user(optval, final, finallen))
+ rc = -EFAULT;
+
+ if (put_user(finallen, optlen))
+ rc = -EFAULT;
+
+ kfree(final);
+ return rc;
}
int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index fcad2e3432d2..5e7d61754798 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4923,10 +4923,8 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
return err;
}
-static int selinux_socket_getpeersec_stream(struct socket *sock,
- char __user *optval,
- int __user *optlen,
- unsigned int len)
+static int selinux_socket_getpeersec_stream(struct socket *sock, char **optval,
+ int *optlen, unsigned int len)
{
int err = 0;
char *scontext;
@@ -4946,18 +4944,12 @@ static int selinux_socket_getpeersec_stream(struct socket *sock,
if (err)
return err;
- if (scontext_len > len) {
+ if (scontext_len > len)
err = -ERANGE;
- goto out_len;
- }
-
- if (copy_to_user(optval, scontext, scontext_len))
- err = -EFAULT;
+ else
+ *optval = scontext;
-out_len:
- if (put_user(scontext_len, optlen))
- err = -EFAULT;
- kfree(scontext);
+ *optlen = scontext_len;
return err;
}
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 7a30b8692b1e..40c75205a914 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3919,28 +3919,29 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
*
* returns zero on success, an error code otherwise
*/
-static int smack_socket_getpeersec_stream(struct socket *sock,
- char __user *optval,
- int __user *optlen, unsigned len)
+static int smack_socket_getpeersec_stream(struct socket *sock, char **optval,
+ int *optlen, unsigned len)
{
- struct socket_smack *ssp;
- char *rcp = "";
- int slen = 1;
+ struct socket_smack *ssp = smack_sock(sock->sk);
+ char *rcp;
+ int slen;
int rc = 0;
- ssp = smack_sock(sock->sk);
- if (ssp->smk_packet != NULL) {
- rcp = ssp->smk_packet->smk_known;
- slen = strlen(rcp) + 1;
+ if (ssp->smk_packet == NULL) {
+ *optlen = 0;
+ return -EINVAL;
}
+ rcp = ssp->smk_packet->smk_known;
+ slen = strlen(rcp) + 1;
if (slen > len)
rc = -ERANGE;
- else if (copy_to_user(optval, rcp, slen) != 0)
- rc = -EFAULT;
-
- if (put_user(slen, optlen) != 0)
- rc = -EFAULT;
+ else {
+ *optval = kstrdup(rcp, GFP_KERNEL);
+ if (*optval == NULL)
+ rc = -ENOMEM;
+ }
+ *optlen = slen;
return rc;
}
--
2.20.1
