add smack_get_peer_label for sockets.

diff --git a/src/smack.c b/src/smack.c
index 4dbdc94..46c8b07 100644 (file)
--- a/src/smack.c
+++ b/src/smack.c
@@ -29,6 +29,7 @@
 #include <uthash.h>
 #include <pthread.h>
 #include <sys/stat.h>
+#include <sys/socket.h>
 
 #define SMACK_LEN 23
 
@@ -447,6 +448,40 @@ int smack_have_access(const char *path, const char *subject,
        return res;
 }
 
+int smack_get_peer_label(int sock_fd, char **label)
+{
+        *label = NULL;
+        char *value;
+        int ret;
+        socklen_t length = SMACK_LEN + 1;
+
+        value = calloc(length, 1);
+        if (!value)
+                return -1;
+
+        ret = getsockopt(sock_fd, SOL_SOCKET, SO_PEERSEC, value, &length);
+        if (ret == -1)
+        {
+                if (errno == ERANGE)
+                {
+                        char *val2;
+                        val2 = realloc(value, length);
+                        if (!val2)
+                                goto err;
+
+                        value = val2;
+                        ret = getsockopt(sock_fd, SOL_SOCKET, SO_PEERSEC, value, &length);
+                }
+        }
+
+        if (ret == 0)
+               *label = strndup(value, length);
+
+err:
+        free(value);
+        return ret;
+}
+
 static int update_rule(struct smack_subject **subjects,
                       const char *subject_str,
                       const char *object_str, unsigned ac)

diff --git a/src/smack.h b/src/smack.h
index 6484a2a..efa6e93 100644 (file)
--- a/src/smack.h
+++ b/src/smack.h
@@ -193,6 +193,16 @@ extern int smack_rule_set_iter_next(SmackRuleSetIter iter,
 extern int smack_have_access(const char *path, const char *subject,
                             const char *object, const char *access_type);
 
+/*!
+  * Get the label that is associated with a peer on the other
+  * end of a socket.
+  *
+  * @param sock_fd The file descriptor of the socket
+  * @param label (out) The NULL terminated label of the socket if it exists, the caller is responsible to call free on label.
+  * @return 0 on success, -1 otherwise.
+  */
+extern int smack_get_peer_label(int sock_fd, char **label);
+
 #ifdef __cplusplus
 }
 #endif