diff options
author | Lennart Poettering <lennart@poettering.net> | 2016-05-05 22:24:36 +0200 |
---|---|---|
committer | Sven Eden <yamakuzure@gmx.net> | 2017-06-16 10:12:58 +0200 |
commit | 34a47924489b195799b36932f56db80f2d4e1ab6 (patch) | |
tree | 067936d960bb2b0f88f24c18fa4615fd14defc43 /src/basic | |
parent | a799bc503d6055ecc97fce94d0685fdfe055a3f4 (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 ca12c8b41..08aa986a0 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; } @@ -216,7 +216,7 @@ 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 449273d9a..8850d9f16 100644 --- a/src/basic/socket-util.h +++ b/src/basic/socket-util.h @@ -143,3 +143,14 @@ int receive_one_fd(int transport_fd, int flags); #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))); \ + }) |