ptrace rules currently take the form of

  ptrace [<ptrace_perms>] [<peer_profile_name>],
  ptrace_perm := read|trace|readby|tracedby
  ptrace_perms := ptrace_perm | '(' ptrace_perm+ ')'

After having used the cross check (permission needed in both profiles)
I am not sure it is correct for ptrace.

Signed-off-by: John Johansen <john.johan...@canonical.com>

---
 parser/Makefile        |    8 ++
 parser/parser.h        |    1 
 parser/parser_common.c |    1 
 parser/parser_lex.l    |   25 +++++++-
 parser/parser_main.c   |    2 
 parser/parser_misc.c   |    3 +
 parser/parser_regex.c  |    4 +
 parser/parser_yacc.y   |   73 +++++++++++++++++++++++++
 parser/ptrace.c        |  139 +++++++++++++++++++++++++++++++++++++++++++++++++
 parser/ptrace.h        |   52 ++++++++++++++++++
 10 files changed, 301 insertions(+), 7 deletions(-)

--- 2.9-test.orig/parser/Makefile
+++ 2.9-test/parser/Makefile
@@ -79,9 +79,10 @@
 SRCS = parser_common.c parser_include.c parser_interface.c parser_lex.c \
        parser_main.c parser_misc.c parser_merge.c parser_symtab.c \
        parser_yacc.c parser_regex.c parser_variable.c parser_policy.c \
-       parser_alias.c mount.c dbus.c lib.c profile.cc rule.c signal.c
+       parser_alias.c mount.c dbus.c lib.c profile.cc rule.c signal.c \
+       ptrace.c
 HDRS = parser.h parser_include.h immunix.h mount.h dbus.h lib.h profile.h \
-       rule.h signal.h
+       rule.h signal.h ptrace.h
 TOOLS = apparmor_parser
 
 OBJECTS = $(SRCS:.c=.o)
@@ -243,6 +244,9 @@
 signal.o: signal.c signal.h parser.h immunix.h parser_yacc.h rule.h 
$(APPARMOR_H)
        $(CXX) $(EXTRA_CFLAGS) -c -o $@ $<
 
+ptrace.o: ptrace.c ptrace.h parser.h immunix.h parser_yacc.h rule.h 
$(APPARMOR_H)
+       $(CXX) $(EXTRA_CFLAGS) -c -o $@ $<
+
 profile.o: profile.cc profile.h parser.h
        $(CXX) $(EXTRA_CFLAGS) -c -o $@ $<
 
--- 2.9-test.orig/parser/parser.h
+++ 2.9-test/parser/parser.h
@@ -265,6 +265,7 @@
 extern int kernel_supports_mount;
 extern int kernel_supports_dbus;
 extern int kernel_supports_signal;
+extern int kernel_supports_ptrace;
 extern int conf_verbose;
 extern int conf_quiet;
 extern int names_only;
--- 2.9-test.orig/parser/parser_common.c
+++ 2.9-test/parser/parser_common.c
@@ -56,6 +56,7 @@
 int kernel_supports_mount = 0;         /* kernel supports mount rules */
 int kernel_supports_dbus = 0;          /* kernel supports dbus rules */
 int kernel_supports_signal = 0;                /* kernel supports signal rules 
*/
+int kernel_supports_ptrace = 0;                /* kernel supports ptrace rules 
*/
 int conf_verbose = 0;
 int conf_quiet = 0;
 int names_only = 0;
--- 2.9-test.orig/parser/parser_lex.l
+++ 2.9-test/parser/parser_lex.l
@@ -254,6 +254,7 @@
 %x MOUNT_MODE
 %x DBUS_MODE
 %x SIGNAL_MODE
+%x PTRACE_MODE
 %x CHANGE_PROFILE_MODE
 %x INCLUDE
 
@@ -268,7 +269,7 @@
        }
 %}
 
-<INITIAL,INCLUDE,LIST_VAL_MODE,EXTCOND_MODE,LIST_COND_VAL,LIST_COND_PAREN_VAL,LIST_COND_MODE,EXTCONDLIST_MODE,ASSIGN_MODE,NETWORK_MODE,CHANGE_PROFILE_MODE,RLIMIT_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE>{
+<INITIAL,INCLUDE,LIST_VAL_MODE,EXTCOND_MODE,LIST_COND_VAL,LIST_COND_PAREN_VAL,LIST_COND_MODE,EXTCONDLIST_MODE,ASSIGN_MODE,NETWORK_MODE,CHANGE_PROFILE_MODE,RLIMIT_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        {WS}+   {  DUMP_PREPROCESS; /* Ignoring whitespace */ }
 }
 
@@ -294,7 +295,7 @@
                yyterminate();
 }
 
-<INITIAL,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE>{
+<INITIAL,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        {VARIABLE_NAME}/{WS}*=  {
                /* we match to the = in the lexer so that we can switch scanner
                 * state.  By the time the parser see the = it may be too late
@@ -470,6 +471,15 @@
 <DBUS_MODE,SIGNAL_MODE>{
        send            { RETURN_TOKEN(TOK_SEND); }
        receive         { RETURN_TOKEN(TOK_RECEIVE); }
+}
+
+<PTRACE_MODE>{
+       trace           { RETURN_TOKEN(TOK_TRACE); }
+       viewedby        { RETURN_TOKEN(TOK_READBY); }
+       tracedby        { RETURN_TOKEN(TOK_TRACEDBY); }
+}
+
+<DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        read            { RETURN_TOKEN(TOK_READ); }
        write           { RETURN_TOKEN(TOK_WRITE); }
        {OPEN_PAREN}    {
@@ -481,9 +491,11 @@
                        }
 }
 
-<MOUNT_MODE,DBUS_MODE,SIGNAL_MODE>{
+<MOUNT_MODE>{
        {ARROW}         { RETURN_TOKEN(TOK_ARROW); }
+}
 
+<MOUNT_MODE,DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        ({IDS_NOEQ}|{PATHNAME}|{QUOTED_ID}) {
                yylval.id = processid(yytext, yyleng);
                RETURN_TOKEN(TOK_ID);
@@ -573,13 +585,15 @@
        case TOK_SIGNAL:
                state = SIGNAL_MODE;
                break;
+       case TOK_PTRACE:
+               state = PTRACE_MODE;
        default: /* nothing */
                break;
        }
        PUSH_AND_RETURN(state, token);
 }
 
-<INITIAL,NETWORK_MODE,RLIMIT_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE>{
+<INITIAL,NETWORK_MODE,RLIMIT_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        {END_OF_RULE}   {
                if (YY_START != INITIAL)
                        POP();
@@ -592,7 +606,7 @@
        }
 }
 
-<INITIAL,SUB_ID,SUB_VALUE,LIST_VAL_MODE,EXTCOND_MODE,LIST_COND_VAL,LIST_COND_PAREN_VAL,LIST_COND_MODE,EXTCONDLIST_MODE,ASSIGN_MODE,NETWORK_MODE,CHANGE_PROFILE_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE>{
+<INITIAL,SUB_ID,SUB_VALUE,LIST_VAL_MODE,EXTCOND_MODE,LIST_COND_VAL,LIST_COND_PAREN_VAL,LIST_COND_MODE,EXTCONDLIST_MODE,ASSIGN_MODE,NETWORK_MODE,CHANGE_PROFILE_MODE,MOUNT_MODE,DBUS_MODE,SIGNAL_MODE,PTRACE_MODE>{
        [^\n]   {
                DUMP_PREPROCESS;
                /* Something we didn't expect */
@@ -620,6 +634,7 @@
        STATE_TABLE_ENT(MOUNT_MODE),
        STATE_TABLE_ENT(DBUS_MODE),
        STATE_TABLE_ENT(SIGNAL_MODE),
+       STATE_TABLE_ENT(PTRACE_MODE),
        STATE_TABLE_ENT(CHANGE_PROFILE_MODE),
        STATE_TABLE_ENT(INCLUDE),
 };
--- 2.9-test.orig/parser/parser_main.c
+++ 2.9-test/parser/parser_main.c
@@ -850,6 +850,8 @@
                kernel_supports_dbus = 1;
        if (strstr(features_string, "signal"))
                kernel_supports_signal = 1;
+       if (strstr(features_string, "ptrace {"))
+               kernel_supports_ptrace = 1;
 }
 
 int process_binary(int option, const char *profilename)
--- 2.9-test.orig/parser/parser_misc.c
+++ 2.9-test/parser/parser_misc.c
@@ -150,6 +150,9 @@
        {"write",               TOK_WRITE},
        {"eavesdrop",           TOK_EAVESDROP},
        {"peer",                TOK_PEER},
+       {"trace",               TOK_TRACE},
+       {"tracedby",            TOK_TRACEDBY},
+       {"readby",              TOK_READBY},
 
        /* terminate */
        {NULL, 0}
--- 2.9-test.orig/parser/parser_regex.c
+++ 2.9-test/parser/parser_regex.c
@@ -674,6 +674,7 @@
 static const char *mediates_mount = CLASS_STR(AA_CLASS_MOUNT);
 static const char *mediates_dbus =  CLASS_STR(AA_CLASS_DBUS);
 static const char *mediates_signal =  CLASS_STR(AA_CLASS_SIGNAL);
+static const char *mediates_ptrace =  CLASS_STR(AA_CLASS_PTRACE);
 
 int process_profile_policydb(Profile *prof)
 {
@@ -703,6 +704,9 @@
        if (kernel_supports_signal &&
            !prof->policy.rules->add_rule(mediates_signal, 0, AA_MAY_READ, 0, 
dfaflags))
                goto out;
+       if (kernel_supports_ptrace &&
+           !prof->policy.rules->add_rule(mediates_ptrace, 0, AA_MAY_READ, 0, 
dfaflags))
+               goto out;
 
        if (prof->policy.rules->rule_count > 0) {
                prof->policy.dfa = 
prof->policy.rules->create_dfa(&prof->policy.size, dfaflags);
--- 2.9-test.orig/parser/parser_yacc.y
+++ 2.9-test/parser/parser_yacc.y
@@ -138,6 +138,9 @@
 %token TOK_WRITE
 %token TOK_EAVESDROP
 %token TOK_PEER
+%token TOK_TRACE
+%token TOK_TRACEDBY
+%token TOK_READBY
 
  /* rlimits */
 %token TOK_RLIMIT
@@ -170,6 +173,7 @@
        #include "mount.h"
        #include "dbus.h"
        #include "signal.h"
+       #include "ptrace.h"
 }
 
 %union {
@@ -184,6 +188,7 @@
        mnt_rule *mnt_entry;
        dbus_rule *dbus_entry;
        signal_rule *signal_entry;
+       ptrace_rule *ptrace_entry;
 
        flagvals flags;
        int fmode;
@@ -250,6 +255,10 @@
 %type <fmode>  signal_perms
 %type <fmode>  opt_signal_perm
 %type <signal_entry>   signal_rule
+%type <fmode>  ptrace_perm
+%type <fmode>  ptrace_perms
+%type <fmode>  opt_ptrace_perm
+%type <ptrace_entry>   ptrace_rule
 %type <transition> opt_named_transition
 %type <boolean> opt_unsafe
 %type <boolean> opt_file
@@ -720,6 +729,22 @@
                $$ = $1;
        }
 
+rules:  rules opt_prefix ptrace_rule
+       {
+               if ($2.owner)
+                       yyerror(_("owner prefix not allowed on ptrace rules"));
+               if ($2.deny && $2.audit) {
+                       $3->deny = 1;
+               } else if ($2.deny) {
+                       $3->deny = 1;
+                       $3->audit = $3->mode;
+               } else if ($2.audit) {
+                       $3->audit = $3->mode;
+               }
+               $1->rule_ents.push_back($3);
+               $$ = $1;
+       }
+
 rules: rules change_profile
        {
                PDEBUG("matched: rules change_profile\n");
@@ -1279,6 +1304,54 @@
                $$ = ent;
        }
 
+ptrace_perm: TOK_VALUE
+       {
+               if (strcmp($1, "trace") == 0 || strcmp($1, "write") == 0)
+                       $$ = AA_MAY_TRACE;
+               else if (strcmp($1, "read") == 0)
+                       $$ = AA_MAY_READ;
+               else if (strcmp($1, "tracedby") == 0)
+                       $$ = AA_MAY_TRACEDBY;
+               else if (strcmp($1, "readby") == 0)
+                       $$ = AA_MAY_READBY;
+               else if ($1)
+                       parse_ptrace_mode($1, &$$, 1);
+               else
+                       $$ = 0;
+
+               if ($1)
+                       free($1);
+       }
+       | TOK_TRACE { $$ = AA_MAY_TRACE; }
+       | TOK_TRACEDBY { $$ = AA_MAY_TRACEDBY; }
+       | TOK_READ { $$ = AA_MAY_READ; }
+       | TOK_WRITE { $$ = AA_MAY_TRACE; }
+       | TOK_READBY { $$ = AA_MAY_READBY; }
+       | TOK_MODE
+       {
+               parse_ptrace_mode($1, &$$, 1);
+               free($1);
+       }
+
+ptrace_perms: { /* nothing */ $$ = 0; }
+       | ptrace_perms ptrace_perm { $$ = $1 | $2; }
+       | ptrace_perms TOK_COMMA ptrace_perm { $$ = $1 | $3; }
+
+opt_ptrace_perm: { /* nothing */ $$ = 0; }
+       | ptrace_perm { $$ = $1; }
+       | TOK_OPENPAREN ptrace_perms TOK_CLOSEPAREN { $$ = $2; }
+
+ptrace_rule: TOK_PTRACE opt_ptrace_perm opt_conds TOK_END_OF_RULE
+       {
+               ptrace_rule *ent = new ptrace_rule($2, $3, NULL);
+               $$ = ent;
+       }
+       |  TOK_PTRACE opt_ptrace_perm opt_conds TOK_ID TOK_END_OF_RULE
+       {
+               ptrace_rule *ent = new ptrace_rule($2, $3, $4);
+               $$ = ent;
+       }
+
 hat_start: TOK_CARET {}
        | TOK_HAT {}
 
--- /dev/null
+++ 2.9-test/parser/ptrace.c
@@ -0,0 +1,139 @@
+/*
+ *   Copyright (c) 2014
+ *   Canonical, Ltd. (All rights reserved)
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of version 2 of the GNU General Public
+ *   License published by the Free Software Foundation.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, contact Novell, Inc. or Canonical
+ *   Ltd.
+ */
+
+#include "parser.h"
+#include "profile.h"
+#include "ptrace.h"
+
+#include <iomanip>
+#include <string>
+#include <sstream>
+
+int parse_ptrace_mode(const char *str_mode, int *mode, int fail)
+{
+       return parse_X_mode("ptrace", AA_VALID_PTRACE_PERMS, str_mode, mode, 
fail);
+}
+
+void ptrace_rule::move_conditionals(struct cond_entry *conds)
+{
+       struct cond_entry *cond_ent;
+
+       list_for_each(conds, cond_ent) {
+               /* for now disallow keyword 'in' (list) */
+               if (!cond_ent->eq)
+                       yyerror("keyword \"in\" is not allowed in ptrace 
rules\n");
+
+               /* no valid conditionals atm */
+               yyerror("invalid ptrace rule conditional \"%s\"\n",
+                       cond_ent->name);
+       }
+}
+
+ptrace_rule::ptrace_rule(int mode_p, struct cond_entry *conds, char *peer):
+       peer_label(peer), audit(0), deny(0)
+{
+       if (mode_p) {
+               if (mode_p & ~AA_VALID_PTRACE_PERMS)
+                       yyerror("mode contains invalid permissions for 
ptrace\n");
+               mode = mode_p;
+       } else {
+               mode = AA_VALID_PTRACE_PERMS;
+       }
+
+       move_conditionals(conds);
+       free_cond_list(conds);
+}
+
+ostream &ptrace_rule::dump(ostream &os)
+{
+       if (audit)
+               os << "audit ";
+       if (deny)
+               os << "deny ";
+
+       os << "ptrace";
+
+       if (mode != AA_VALID_PTRACE_PERMS) {
+               os << " (";
+
+               if (mode & AA_MAY_READ)
+                       os << "read ";
+               if (mode & AA_MAY_READBY)
+                       os << "readby ";
+               if (mode & AA_MAY_TRACE)
+                       os << "trace ";
+               if (mode & AA_MAY_TRACEDBY)
+                       os << "tracedby ";
+               os << ")";
+       }
+
+       if (peer_label)
+               os << " " << peer_label;
+
+       os << ",\n";
+
+       return os;
+}
+
+
+int ptrace_rule::expand_variables(void)
+{
+       return expand_entry_variables(&peer_label);
+}
+
+int ptrace_rule::gen_policy_re(Profile &prof)
+{
+       std::ostringstream buffer;
+       std::string buf;
+
+       pattern_t ptype;
+       int pos;
+
+       /* ?? do we want to generate the rules in the policy so that it
+        * the compile could be used on another kernel unchanged??
+        * Current caching doesn't support this but in the future maybe
+        */
+       if (!kernel_supports_ptrace) {
+               pwarn("profile %s ptrace rules not enforced\n", prof.name);
+               return RULE_NOT_SUPPORTED;
+       }
+
+       buffer << "\\x" << std::setfill('0') << std::setw(2) << std::hex << 
AA_CLASS_PTRACE;
+
+       if (peer_label) {
+               ptype = convert_aaregex_to_pcre(peer_label, 0, buf, &pos);
+               if (ptype == ePatternInvalid)
+                       goto fail;
+               buffer << buf;
+       } else {
+               buffer << anyone_match_pattern;
+       }
+
+       buf = buffer.str();
+       if (mode & AA_VALID_PTRACE_PERMS) {
+               if (!prof.policy.rules->add_rule(buf.c_str(), deny, mode, audit,
+                                                dfaflags))
+                       goto fail;
+       }
+
+       return RULE_OK;
+
+fail:
+       return RULE_ERROR;
+}
+
--- /dev/null
+++ 2.9-test/parser/ptrace.h
@@ -0,0 +1,52 @@
+/*
+ *   Copyright (c) 2014
+ *   Canonical Ltd. (All rights reserved)
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of version 2 of the GNU General Public
+ *   License published by the Free Software Foundation.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, contact Novell, Inc. or Canonical
+ *   Ltd.
+ */
+#ifndef __AA_PTRACE_H
+#define __AA_PTRACE_H
+
+#include "immunix.h"
+#include "parser.h"
+
+#define AA_MAY_TRACE   AA_MAY_WRITE
+#define AA_MAY_READBY  0x10            /* MAY_CREATE in new encoding */
+#define AA_MAY_TRACEDBY        AA_MAY_APPEND
+#define AA_VALID_PTRACE_PERMS (AA_MAY_READ | AA_MAY_TRACE | AA_MAY_READBY | \
+                              AA_MAY_TRACEDBY)
+
+int parse_ptrace_mode(const char *str_mode, int *mode, int fail);
+
+class ptrace_rule: public rule_t {
+       void move_conditionals(struct cond_entry *conds);
+public:
+       char *peer_label;
+       int mode;
+       int audit;
+       int deny;
+
+       ptrace_rule(int mode, struct cond_entry *conds, char *peer);
+       virtual ~ptrace_rule()
+       {
+               free(peer_label);
+       };
+
+       virtual ostream &dump(ostream &os);
+       virtual int expand_variables(void);
+       virtual int gen_policy_re(Profile &prof);
+       virtual void post_process(Profile &prof __unused) { };
+};
+
+#endif /* __AA_PTRACE_H */


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