From 087516c0b4020534a666b0488e44bf8e1c8b4d53 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Wed, 10 Jun 2015 18:26:16 +0200 Subject: [PATCH] bus: fix bloom_add_prefixes() to add all required data Lets look at an example where we add arg0="/foo/bar/waldo" to a bloom-filter. The following strings are added: "arg0:/foo/bar/waldo" "arg0-slash-prefix:/foo/bar" "arg0-slash-prefix:/foo" Two problems arise: 1) If we match on "arg0path=/foo/bar/waldo", the dbus-spec explicitly states that equal strings are also considered prefixes. However, in the bloom-match, we can only provide a single match-filter. Therefore, we have to add "arg0-slash-prefix:/foo/bar/waldo" there, but this never occured in the bloom-mask of the message. Hence, this patch makes sure bloom_add_prefixes() adds the full path as prefix, too. 2) If we match on "arg0path=/foo/", the dbus-spec states that arg0path does prefix-matching with the trailing slash _included_, unlike path_namespace= matches, which does *not* include them. This is inconsistent, but we have to support the specs. Therefore, we must add prefixes with _and_ without trailing separators. Hence, this patch makes sure bloom_add_prefixes() adds all prefixes with the trailing slash included. The final set of strings added therefore is: "arg0:/foo/bar/waldo" "arg0-slash-prefix:/foo/bar/waldo" "arg0-slash-prefix:/foo/bar/" "arg0-slash-prefix:/foo/bar" "arg0-slash-prefix:/foo/" "arg0-slash-prefix:/foo" "arg0-slash-prefix:/" --- src/libelogind/sd-bus/bus-bloom.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/src/libelogind/sd-bus/bus-bloom.c b/src/libelogind/sd-bus/bus-bloom.c index 355677407..91fab90cb 100644 --- a/src/libelogind/sd-bus/bus-bloom.c +++ b/src/libelogind/sd-bus/bus-bloom.c @@ -116,11 +116,19 @@ void bloom_add_prefixes(uint64_t filter[], size_t size, unsigned k, const char * p = stpcpy(stpcpy(c, a), ":"); strcpy(p, b); + bloom_add_data(filter, size, k, c, n); + for (;;) { char *e; e = strrchr(p, sep); - if (!e || e == p) + if (!e) + break; + + *(e + 1) = 0; + bloom_add_data(filter, size, k, c, e - c + 1); + + if (e == p) break; *e = 0; -- 2.30.2