From deac9731884a83ad91eab9f27b288f406f56c87b Mon Sep 17 00:00:00 2001 From: Levente Polyak Date: Sat, 18 Jul 2015 17:58:23 +0200 Subject: ensure matching database and package version While loading each package ensure that the internal version matches the expected database version to avoid the possibility to circumvent the version check. This issue can be used by an attacker to trick the software into installing an older version. The behavior can be exploited by a man-in-the-middle attack through specially crafted database tarball containing a higher version, yet actually delivering an older and vulnerable version, which was previously shipped. Signed-off-by: Levente Polyak Signed-off-by: Remi Gacogne Signed-off-by: Allan McRae --- lib/libalpm/sync.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'lib/libalpm/sync.c') diff --git a/lib/libalpm/sync.c b/lib/libalpm/sync.c index 888ae15e..e843b07a 100644 --- a/lib/libalpm/sync.c +++ b/lib/libalpm/sync.c @@ -1212,6 +1212,7 @@ static int load_packages(alpm_handle_t *handle, alpm_list_t **data, EVENT(handle, &event); for(i = handle->trans->add; i; i = i->next, current++) { + int error = 0; alpm_pkg_t *spkg = i->data; char *filepath; int percent = (int)(((double)current_bytes / total_bytes) * 100); @@ -1232,6 +1233,23 @@ static int load_packages(alpm_handle_t *handle, alpm_list_t **data, spkg->name); alpm_pkg_t *pkgfile =_alpm_pkg_load_internal(handle, filepath, 1); if(!pkgfile) { + _alpm_log(handle, ALPM_LOG_DEBUG, "failed to load pkgfile internal\n"); + error = 1; + } else { + if(strcmp(spkg->name, pkgfile->name) != 0) { + _alpm_log(handle, ALPM_LOG_DEBUG, + "internal package name mismatch, expected: '%s', actual: '%s'\n", + spkg->name, pkgfile->name); + error = 1; + } + if(strcmp(spkg->version, pkgfile->version) != 0) { + _alpm_log(handle, ALPM_LOG_DEBUG, + "internal package version mismatch, expected: '%s', actual: '%s'\n", + spkg->version, pkgfile->version); + error = 1; + } + } + if(error != 0) { errors++; *data = alpm_list_add(*data, strdup(spkg->filename)); free(filepath); -- cgit v1.2.3-24-g4f1b