X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fcore%2Fmachine-id-setup.c;h=608b0a5e7e07fc5dbc15b4b91cea7232a6bb6f47;hb=a6b26d9011de60e1c41f51e8d2aab1d2f7bbf0f5;hp=ca163978f39a885142dade4023c01f2192ed885a;hpb=a5c32cff1f56afe6f0c6c70d91a88a7a8238b2d7;p=elogind.git diff --git a/src/core/machine-id-setup.c b/src/core/machine-id-setup.c index ca163978f..608b0a5e7 100644 --- a/src/core/machine-id-setup.c +++ b/src/core/machine-id-setup.c @@ -151,62 +151,53 @@ static int generate(char id[34]) { } int machine_id_setup(void) { - int fd, r; + _cleanup_close_ int fd = -1; + int r; bool writable; struct stat st; char id[34]; /* 32 + \n + \0 */ - mode_t m; - - m = umask(0000); - - /* We create this 0444, to indicate that this isn't really - * something you should ever modify. Of course, since the file - * will be owned by root it doesn't matter much, but maybe - * people look. */ - - fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444); - if (fd >= 0) - writable = true; - else { - fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY); - if (fd < 0) { - umask(m); - log_error("Cannot open /etc/machine-id: %m"); - return -errno; - } - writable = false; - } + RUN_WITH_UMASK(0000) { + /* We create this 0444, to indicate that this isn't really + * something you should ever modify. Of course, since the file + * will be owned by root it doesn't matter much, but maybe + * people look. */ + + fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444); + if (fd >= 0) + writable = true; + else { + fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (fd < 0) { + log_error("Cannot open /etc/machine-id: %m"); + return -errno; + } - umask(m); + writable = false; + } + } if (fstat(fd, &st) < 0) { log_error("fstat() failed: %m"); - r = -errno; - goto finish; + return -errno; } - if (S_ISREG(st.st_mode)) { - if (loop_read(fd, id, 32, false) >= 32) { - r = 0; - goto finish; - } - } + if (S_ISREG(st.st_mode)) + if (loop_read(fd, id, 32, false) >= 32) + return 0; /* Hmm, so, the id currently stored is not useful, then let's * generate one */ r = generate(id); if (r < 0) - goto finish; + return r; if (S_ISREG(st.st_mode) && writable) { lseek(fd, 0, SEEK_SET); - if (loop_write(fd, id, 33, false) == 33) { - r = 0; - goto finish; - } + if (loop_write(fd, id, 33, false) == 33) + return 0; } close_nointr_nofail(fd); @@ -215,33 +206,28 @@ int machine_id_setup(void) { /* Hmm, we couldn't write it? So let's write it to * /run/machine-id as a replacement */ - m = umask(0022); - r = write_one_line_file("/run/machine-id", id); - umask(m); - + RUN_WITH_UMASK(0022) { + r = write_string_file("/run/machine-id", id); + } if (r < 0) { log_error("Cannot write /run/machine-id: %s", strerror(-r)); - unlink("/run/machine-id"); - goto finish; + return r; } /* And now, let's mount it over */ - r = mount("/run/machine-id", "/etc/machine-id", NULL, MS_BIND, NULL) < 0 ? -errno : 0; + r = mount("/run/machine-id", "/etc/machine-id", NULL, MS_BIND, NULL); if (r < 0) { - unlink("/run/machine-id"); - log_error("Failed to mount /etc/machine-id: %s", strerror(-r)); - } else { - log_info("Installed transient /etc/machine-id file."); - - /* Mark the mount read-only */ - mount(NULL, "/etc/machine-id", NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, NULL); + log_error("Failed to mount /etc/machine-id: %m"); + unlink_noerrno("/run/machine-id"); + return -errno; } -finish: + log_info("Installed transient /etc/machine-id file."); - if (fd >= 0) - close_nointr_nofail(fd); + /* Mark the mount read-only */ + if (mount(NULL, "/etc/machine-id", NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, NULL) < 0) + log_warning("Failed to make transient /etc/machine-id read-only: %m"); - return r; + return 0; }