X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fmachine-id-setup.c;h=531f3b207382b4709a3bc6db51f9a5dac8ce93d1;hp=65792e9b842357b2f0b87e1f08403a64a094ddb4;hb=ba1d5596354e3299d5b9b995bb0fa9b3bdd285cc;hpb=76526bad9fbe936af69baec576674135585e6130 diff --git a/src/machine-id-setup.c b/src/machine-id-setup.c index 65792e9b8..531f3b207 100644 --- a/src/machine-id-setup.c +++ b/src/machine-id-setup.c @@ -27,21 +27,25 @@ #include #include +#include + #include "machine-id-setup.h" #include "macro.h" #include "util.h" #include "log.h" static int generate(char id[34]) { - int fd; - char buf[16]; - char *p, *q; + int fd, r; + unsigned char *p; + sd_id128_t buf; + char *q; ssize_t k; assert(id); /* First, try reading the D-Bus machine id, unless it is a symlink */ - if ((fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW)) >= 0) { + fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); + if (fd >= 0) { k = loop_read(fd, id, 33, false); close_nointr_nofail(fd); @@ -56,20 +60,13 @@ static int generate(char id[34]) { } /* If that didn't work, generate a random machine id */ - if ((fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) { - log_error("Failed to open /dev/urandom: %m"); - return -errno; - } - - k = loop_read(fd, buf, sizeof(buf), false); - close_nointr_nofail(fd); - - if (k != sizeof(buf)) { - log_error("Failed to read /dev/urandom: %s", strerror(k < 0 ? -k : EIO)); - return k < 0 ? (int) k : -EIO; + r = sd_id128_randomize(&buf); + if (r < 0) { + log_error("Failed to open /dev/urandom: %s", strerror(-r)); + return r; } - for (p = buf, q = id; p < buf + sizeof(buf); p++, q += 2) { + for (p = buf.bytes, q = id; p < buf.bytes + sizeof(buf); p++, q += 2) { q[0] = hexchar(*p >> 4); q[1] = hexchar(*p & 15); } @@ -96,10 +93,12 @@ int machine_id_setup(void) { * will be owned by root it doesn't matter much, but maybe * people look. */ - if ((fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444)) >= 0) + fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444); + if (fd >= 0) writable = true; else { - if ((fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) { + 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; @@ -126,7 +125,8 @@ int machine_id_setup(void) { /* Hmm, so, the id currently stored is not useful, then let's * generate one */ - if ((r = generate(id)) < 0) + r = generate(id); + if (r < 0) goto finish; if (S_ISREG(st.st_mode) && writable) { @@ -142,20 +142,24 @@ int machine_id_setup(void) { fd = -1; /* Hmm, we couldn't write it? So let's write it to - * /dev/.systemd/machine-id as a replacement */ + * /run/systemd/machine-id as a replacement */ - mkdir_p("/dev/.systemd", 0755); + mkdir_p("/run/systemd", 0755); + + m = umask(0022); + r = write_one_line_file("/run/systemd/machine-id", id); + umask(m); - if ((r = write_one_line_file("/dev/.systemd/machine-id", id)) < 0) { - log_error("Cannot write /dev/.systemd/machine-id: %s", strerror(-r)); + if (r < 0) { + log_error("Cannot write /run/systemd/machine-id: %s", strerror(-r)); - unlink("/dev/.systemd/machine-id"); + unlink("/run/systemd/machine-id"); goto finish; } /* And now, let's mount it over */ - r = mount("/dev/.systemd/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0; - unlink("/dev/.systemd/machine-id"); + r = mount("/run/systemd/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0; + unlink("/run/systemd/machine-id"); if (r < 0) log_error("Failed to mount /etc/machine-id: %s", strerror(-r));