1 files changed, 102 insertions, 0 deletions
diff --git a/test/packetdrill/capability.h b/test/packetdrill/capability.h
new file mode 100644
index 0000000..7ec5ee2
--- /dev/null
+++ b/test/packetdrill/capability.h
@@ -0,0 +1,102 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+// Author: willemb@google.com (Will de Bruijn)
+//
+// POSIX capability support for Linux: simplified libcap
+// GPL applies, as this interface was inspired by sys/capability.h
+
+#ifndef _LINUX_GTESTS_NET_CAPABILITY_H
+#define _LINUX_GTESTS_NET_CAPABILITY_H
+
+#ifdef HAVE_SYS_CAPABILITY_H
+#include <sys/capability.h>
+#else
+#include <linux/capability.h>
+
+typedef struct __user_cap_data_struct *cap_t;
+typedef int cap_value_t;
+
+typedef enum {
+	CAP_EFFECTIVE=0,
+	CAP_PERMITTED=1,
+	CAP_INHERITABLE=2
+} cap_flag_t;
+
+typedef enum {
+	CAP_CLEAR=0,
+	CAP_SET=1
+} cap_flag_value_t;
+
+static struct __user_cap_header_struct header = {
+	.version = _LINUX_CAPABILITY_VERSION_3,
+	.pid = 0,
+};
+
+// System calls: implemented in libc
+int capset(cap_user_header_t header, cap_user_data_t data);
+int capget(cap_user_header_t header, const cap_user_data_t data);
+
+// Extract a value for one name in one of the capability lists
+// only supports flag CAP_EFFECTIVE
+static inline int
+cap_get_flag(cap_t cap, cap_value_t name, cap_flag_t flag, cap_flag_value_t *val)
+{
+	assert(flag == CAP_EFFECTIVE);
+	assert(name < (sizeof(cap->effective) * 8));
+	*val = (cap->effective & (1 << name)) ? CAP_SET : CAP_CLEAR;
+	return 0;
+}
+
+// Set the value for a number of names in one of the capability lists
+// only supports flag CAP_EFFECTIVE
+static inline int
+cap_set_flag(cap_t cap, cap_flag_t flag, int num_name,
+	     const cap_value_t *names, cap_flag_value_t val)
+{
+	int i;
+
+	assert(flag == CAP_EFFECTIVE);
+	if (val == CAP_SET)
+		for (i = 0; i < num_name; i++)
+			cap->effective |= (1 << names[i]);
+	else
+		for (i = 0; i < num_name; i++)
+			cap->effective &= ~(1 << names[i]);
+
+	return 0;
+}
+
+// Get the capability lists from the kernel
+static inline cap_t
+cap_get_proc(void)
+{
+	cap_t capabilities = calloc(_LINUX_CAPABILITY_U32S_3,
+				    sizeof(struct __user_cap_data_struct));
+	if (capget(&header, capabilities)) {
+		perror("capget");
+		return NULL;
+	}
+
+	return capabilities;
+}
+
+// Update the capability lists in the kernel
+static inline int
+cap_set_proc(cap_t capabilities)
+{
+	if (capset(&header, capabilities)) {
+		perror("capset");
+		return -1;
+	}
+	return 0;
+}
+
+// Free a capability list
+static inline int
+cap_free(void *capabilities)
+{
+	free(capabilities);
+	return 0;
+}
+
+#endif /* !HAVE_SYS_CAPABILITY_H */
+#endif /* _LINUX_GTESTS_NET_CAPABILITY_H */