[tor-commits] [tor/master] added experimental support for open syscall path param

[nickm at torproject.org]

commit c15d09293bdfc90e94ef34369205cc6db9882607
Author: Cristian Toader <cristian.matei.toader at gmail.com>
Date:   Tue Jul 23 14:01:53 2013 +0300

    added experimental support for open syscall path param
---
 src/common/compat.c  |    1 +
 src/common/sandbox.c |   39 +++++++++++++++++++++++++++++++++------
 src/common/sandbox.h |    2 +-
 src/or/routerlist.c  |    2 +-
 4 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/src/common/compat.c b/src/common/compat.c
index 69eb064..5b15367 100644
--- a/src/common/compat.c
+++ b/src/common/compat.c
@@ -125,6 +125,7 @@ tor_open_cloexec(const char *path, int flags, unsigned mode)
 {
   int fd;
 #ifdef O_CLOEXEC
+  path = get_prot_param(path);
   fd = open(path, flags|O_CLOEXEC, mode);
   if (fd >= 0)
     return fd;
diff --git a/src/common/sandbox.c b/src/common/sandbox.c
index 7c73215..143995d 100644
--- a/src/common/sandbox.c
+++ b/src/common/sandbox.c
@@ -46,7 +46,34 @@ static ParFilter param_filter[] = {
     {SCMP_SYS(rt_sigaction), PARAM_NUM, (intptr_t)(SIGXFSZ), 0},
 #endif
     {SCMP_SYS(rt_sigaction), PARAM_NUM, (intptr_t)(SIGCHLD), 0},
-
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-certs"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-consensus"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/unverified-consensus"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-microdesc-consensus"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-microdesc-consensus.tmp"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-microdescs"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-microdescs.new"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/unverified-microdesc-consensus"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-descriptors"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-descriptors.new"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/cached-extrainfo"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/state.tmp"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/unparseable-desc.tmp"), 0},
+    {SCMP_SYS(open), PARAM_PTR,
+        (intptr_t)("/home/cristi/.tor/unparseable-desc"), 0},
 };
 
 /** Variable used for storing all syscall numbers that will be allowed with the
@@ -106,7 +133,6 @@ static int general_filter[] = {
     SCMP_SYS(mprotect),
     SCMP_SYS(mremap),
     SCMP_SYS(munmap),
-    SCMP_SYS(open),
     SCMP_SYS(openat),
     SCMP_SYS(poll),
     SCMP_SYS(prctl),
@@ -175,13 +201,14 @@ get_prot_param(char *param)
   }
 
   for (i = 0; i < filter_size; i++) {
-    if (param_filter[i].prot && !strncmp(param, (char*) param_filter[i].param,
-        MAX_PARAM_LEN) && param_filter[i].ptype == PARAM_PTR) {
+    if (param_filter[i].prot  && param_filter[i].ptype == PARAM_PTR
+        && !strncmp(param, (char*)(param_filter[i].param), MAX_PARAM_LEN)) {
       return (char*)(param_filter[i].param);
     }
   }
 
-  return NULL;
+  log_warn(LD_BUG, "(Sandbox) Parameter %s not found", param);
+  return param;
 }
 
 static int
@@ -213,7 +240,7 @@ add_param_filter(scmp_filter_ctx ctx)
       }
 
       // copying from non protected to protected + pointer reassign
-      memcpy(map, (char*) param_filter[i].param, param_size);
+      memcpy(map, (char*) (param_filter[i].param), param_size);
       param_filter[i].param = (intptr_t) map;
 
       // protecting from writes
diff --git a/src/common/sandbox.h b/src/common/sandbox.h
index de5699e..b973d97 100644
--- a/src/common/sandbox.h
+++ b/src/common/sandbox.h
@@ -32,7 +32,7 @@
 #define __USE_GNU
 #include <sys/ucontext.h>
 
-#define MAX_PARAM_LEN 32
+#define MAX_PARAM_LEN 64
 
 #define PARAM_PTR 0
 #define PARAM_NUM 1
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index a145ba7..465aaed 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -37,7 +37,7 @@
 #include "routerlist.h"
 #include "routerparse.h"
 #include "routerset.h"
-
+#include "../common/sandbox.h"
 // #define DEBUG_ROUTERLIST
 
 /****************************************************************************/