From 744dccdd361afff8220221c1d385cf54aeb823e0 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Wed, 10 Jun 2015 19:34:05 +0200 Subject: [PATCH] bus: fix pattern matching DBus-spec defines two different pattern matchings: 1) Path and namespace prefix matching. In this case, A matches B either if both are equal, or if B is fully included in the namespace of A. In other words, A has to be a prefix of B, but end with a separator character (or the following character in B must be one). This is used for path_namespace= and arg0namespace= 2) The other pattern matching is used for arg0path= which does a two-way matching. That is, A must be a prefix of B, or B a prefix of A. Furthermore, the prefix must end with a separator. Fix the sd-bus helpers to reflect that. The 'simple_' and 'complex_' prefixes don't make any sense now, but.. eh.. --- src/libsystemd/sd-bus/bus-internal.c | 30 ++++++++++++++++--- src/libsystemd/sd-bus/test-bus-kernel-bloom.c | 10 +++++++ src/libsystemd/sd-bus/test-bus-signature.c | 13 +++++--- 3 files changed, 45 insertions(+), 8 deletions(-) diff --git a/src/libsystemd/sd-bus/bus-internal.c b/src/libsystemd/sd-bus/bus-internal.c index 91b288cd255..37793e48edb 100644 --- a/src/libsystemd/sd-bus/bus-internal.c +++ b/src/libsystemd/sd-bus/bus-internal.c @@ -211,6 +211,17 @@ bool member_name_is_valid(const char *p) { return true; } +/* + * Complex pattern match + * This checks whether @a is a 'complex-prefix' of @b, or @b is a + * 'complex-prefix' of @a, based on strings that consist of labels with @c as + * spearator. This function returns true if: + * - both strings are equal + * - either is a prefix of the other and ends with @c + * The second rule makes sure that either string needs to be fully included in + * the other, and the string which is considered the prefix needs to end with a + * separator. + */ static bool complex_pattern_check(char c, const char *a, const char *b) { bool separator = false; @@ -222,9 +233,7 @@ static bool complex_pattern_check(char c, const char *a, const char *b) { for (;;) { if (*a != *b) - return (separator && (*a == 0 || *b == 0)) || - (*a == 0 && *b == c && b[1] == 0) || - (*b == 0 && *a == c && a[1] == 0); + return (separator && (*a == 0 || *b == 0)); if (*a == 0) return true; @@ -243,7 +252,18 @@ bool path_complex_pattern(const char *pattern, const char *value) { return complex_pattern_check('/', pattern, value); } +/* + * Simple pattern match + * This checks whether @a is a 'simple-prefix' of @b, based on strings that + * consist of labels with @c as separator. This function returns true, if: + * - if @a and @b are equal + * - if @a is a prefix of @b, and the first following character in @b (or the + * last character in @a) is @c + * The second rule basically makes sure that if @a is a prefix of @b, then @b + * must follow with a new label separated by @c. It cannot extend the label. + */ static bool simple_pattern_check(char c, const char *a, const char *b) { + bool separator = false; if (!a && !b) return true; @@ -253,11 +273,13 @@ static bool simple_pattern_check(char c, const char *a, const char *b) { for (;;) { if (*a != *b) - return *a == 0 && *b == c; + return *a == 0 && (*b == c || separator); if (*a == 0) return true; + separator = *a == c; + a++, b++; } } diff --git a/src/libsystemd/sd-bus/test-bus-kernel-bloom.c b/src/libsystemd/sd-bus/test-bus-kernel-bloom.c index 8ebbbfaaac3..01f784f8c23 100644 --- a/src/libsystemd/sd-bus/test-bus-kernel-bloom.c +++ b/src/libsystemd/sd-bus/test-bus-kernel-bloom.c @@ -124,5 +124,15 @@ int main(int argc, char *argv[]) { test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path_namespace='/'", true); test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path_namespace='/quux'", false); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path='/foo/bar/waldo/'", false); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path='/foo/'", false); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path_namespace='/foo/bar/waldo/'", false); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "foobar", "path_namespace='/foo/'", true); + + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "/foo/bar/waldo", "arg0path='/foo/'", true); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "/foo", "arg0path='/foo'", true); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "/foo", "arg0path='/foo/bar/waldo'", false); + test_one("/foo/bar/waldo", "waldo.com", "Piep", false, "/foo/", "arg0path='/foo/bar/waldo'", true); + return 0; } diff --git a/src/libsystemd/sd-bus/test-bus-signature.c b/src/libsystemd/sd-bus/test-bus-signature.c index 4165c9273a1..17c6188ca01 100644 --- a/src/libsystemd/sd-bus/test-bus-signature.c +++ b/src/libsystemd/sd-bus/test-bus-signature.c @@ -95,23 +95,28 @@ int main(int argc, char *argv[]) { assert_se(!namespace_complex_pattern("foo.", "")); assert_se(path_complex_pattern("", "")); - assert_se(path_complex_pattern("", "/")); - assert_se(path_complex_pattern("/", "")); + assert_se(!path_complex_pattern("", "/")); + assert_se(!path_complex_pattern("/", "")); assert_se(path_complex_pattern("/", "/")); assert_se(path_complex_pattern("/foobar/", "/")); - assert_se(path_complex_pattern("/foobar/", "/foobar")); + assert_se(!path_complex_pattern("/foobar/", "/foobar")); assert_se(path_complex_pattern("/foobar", "/foobar")); - assert_se(path_complex_pattern("/foobar", "/foobar/")); + assert_se(!path_complex_pattern("/foobar", "/foobar/")); assert_se(!path_complex_pattern("/foobar", "/foobar/waldo")); assert_se(path_complex_pattern("/foobar/", "/foobar/waldo")); + assert_se(path_complex_pattern("/foobar/waldo", "/foobar/")); + + assert_se(path_simple_pattern("/foo/", "/foo/bar/waldo")); assert_se(namespace_simple_pattern("", "")); + assert_se(namespace_simple_pattern("", ".foobar")); assert_se(namespace_simple_pattern("foobar", "foobar")); assert_se(namespace_simple_pattern("foobar.waldo", "foobar.waldo")); assert_se(namespace_simple_pattern("foobar", "foobar.waldo")); assert_se(!namespace_simple_pattern("foobar.waldo", "foobar")); assert_se(!namespace_simple_pattern("", "foo")); assert_se(!namespace_simple_pattern("foo", "")); + assert_se(namespace_simple_pattern("foo.", "foo.bar.waldo")); assert_se(streq(object_path_startswith("/foo/bar", "/foo"), "bar")); assert_se(streq(object_path_startswith("/foo", "/foo"), ""));