apparmor: allow ptrace checks to be finer grained than just capability

[uclinux-h8/linux.git] / security / apparmor / ipc.c

diff --git a/security/apparmor/ipc.c b/security/apparmor/ipc.c
index f816493..11e66b5 100644 (file)
--- a/security/apparmor/ipc.c
+++ b/security/apparmor/ipc.c
@@ -21,20 +21,76 @@
 #include "include/policy.h"
 #include "include/ipc.h"
 
+/**
+ * audit_ptrace_mask - convert mask to permission string
+ * @buffer: buffer to write string to (NOT NULL)
+ * @mask: permission mask to convert
+ */
+static void audit_ptrace_mask(struct audit_buffer *ab, u32 mask)
+{
+       switch (mask) {
+       case MAY_READ:
+               audit_log_string(ab, "read");
+               break;
+       case MAY_WRITE:
+               audit_log_string(ab, "trace");
+               break;
+       case AA_MAY_BE_READ:
+               audit_log_string(ab, "readby");
+               break;
+       case AA_MAY_BE_TRACED:
+               audit_log_string(ab, "tracedby");
+               break;
+       }
+}
+
 /* call back to audit ptrace fields */
 static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
 {
        struct common_audit_data *sa = va;
 
+       if (aad(sa)->request & AA_PTRACE_PERM_MASK) {
+               audit_log_format(ab, " requested_mask=");
+               audit_ptrace_mask(ab, aad(sa)->request);
+
+               if (aad(sa)->denied & AA_PTRACE_PERM_MASK) {
+                       audit_log_format(ab, " denied_mask=");
+                       audit_ptrace_mask(ab, aad(sa)->denied);
+               }
+       }
        audit_log_format(ab, " peer=");
        aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
                        FLAGS_NONE, GFP_ATOMIC);
 }
 
+/* TODO: conditionals */
+static int profile_ptrace_perm(struct aa_profile *profile,
+                              struct aa_profile *peer, u32 request,
+                              struct common_audit_data *sa)
+{
+       struct aa_perms perms = { };
+
+       /* need because of peer in cross check */
+       if (profile_unconfined(profile) ||
+           !PROFILE_MEDIATES(profile, AA_CLASS_PTRACE))
+               return 0;
+
+       aad(sa)->peer = &peer->label;
+       aa_profile_match_label(profile, &peer->label, AA_CLASS_PTRACE, request,
+                              &perms);
+       aa_apply_modes_to_perms(profile, &perms);
+       return aa_check_perms(profile, &perms, request, sa, audit_ptrace_cb);
+}
+
 static int cross_ptrace_perm(struct aa_profile *tracer,
                             struct aa_profile *tracee, u32 request,
                             struct common_audit_data *sa)
 {
+       if (PROFILE_MEDIATES(tracer, AA_CLASS_PTRACE))
+               return xcheck(profile_ptrace_perm(tracer, tracee, request, sa),
+                             profile_ptrace_perm(tracee, tracer,
+                                                 request << PTRACE_PERM_SHIFT,
+                                                 sa));
        /* policy uses the old style capability check for ptrace */
        if (profile_unconfined(tracer) || tracer == tracee)
                return 0;