diff options
| author | Lennart Poettering <lennart@poettering.net> | 2016-05-05 22:24:36 +0200 |
|---|---|---|
| committer | Lennart Poettering <lennart@poettering.net> | 2016-05-05 22:24:36 +0200 |
| commit | fc2fffe7706ef269005bf4eef56570346c9ca3da (patch) | |
| tree | 9e89ac76ee15de498d97b0d03ed7d764b61874ce /src/basic | |
| parent | d8fdc62037b5b0a9fd603ad5efd6b49f956f86b5 (diff) | |
tree-wide: introduce new SOCKADDR_UN_LEN() macro, and use it everywhere
The macro determines the right length of a AF_UNIX "struct sockaddr_un" to pass to
connect() or bind(). It automatically figures out if the socket refers to an
abstract namespace socket, or a socket in the file system, and properly handles
the full length of the path field.
This macro is not only safer, but also simpler to use, than the usual
offsetof() + strlen() logic.
Diffstat (limited to 'src/basic')
| -rw-r--r-- | src/basic/log.c | 6 | ||||
| -rw-r--r-- | src/basic/socket-util.h | 11 |
2 files changed, 14 insertions, 3 deletions
diff --git a/src/basic/log.c b/src/basic/log.c index d89e6f7274..3ea643b6e6 100644 --- a/src/basic/log.c +++ b/src/basic/log.c @@ -165,7 +165,7 @@ static int log_open_syslog(void) { goto fail; } - if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) { safe_close(syslog_fd); /* Some legacy syslog systems still use stream @@ -177,7 +177,7 @@ static int log_open_syslog(void) { goto fail; } - if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) { r = -errno; goto fail; } @@ -215,7 +215,7 @@ static int log_open_journal(void) { goto fail; } - if (connect(journal_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + if (connect(journal_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) { r = -errno; goto fail; } diff --git a/src/basic/socket-util.h b/src/basic/socket-util.h index d17a2f35f8..daa4b24a37 100644 --- a/src/basic/socket-util.h +++ b/src/basic/socket-util.h @@ -137,3 +137,14 @@ ssize_t next_datagram_size_fd(int fd); #define CMSG_FOREACH(cmsg, mh) \ for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg))) + +/* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */ +#define SOCKADDR_UN_LEN(sa) \ + ({ \ + const struct sockaddr_un *_sa = &(sa); \ + assert(_sa->sun_family == AF_UNIX); \ + offsetof(struct sockaddr_un, sun_path) + \ + (_sa->sun_path[0] == 0 ? \ + 1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \ + strnlen(_sa->sun_path, sizeof(_sa->sun_path))); \ + }) |