diff options
author | Lennart Poettering <lennart@poettering.net> | 2012-04-13 17:10:21 +0200 |
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committer | Lennart Poettering <lennart@poettering.net> | 2012-04-13 18:52:53 +0200 |
commit | 2c3ff76eb004d71a70cb5e253cbca7332c53ac09 (patch) | |
tree | 164e775e3ff63290eeeab5c76ebafeff69be7284 /src/core | |
parent | manager: support systems lacking /dev/tty0 (diff) | |
download | systemd-2c3ff76eb004d71a70cb5e253cbca7332c53ac09.tar.xz systemd-2c3ff76eb004d71a70cb5e253cbca7332c53ac09.zip |
loopback: handle EPERM more gracefully
Diffstat (limited to '')
-rw-r--r-- | src/core/loopback-setup.c | 73 |
1 files changed, 58 insertions, 15 deletions
diff --git a/src/core/loopback-setup.c b/src/core/loopback-setup.c index 46c1fc843a..065b75a6e3 100644 --- a/src/core/loopback-setup.c +++ b/src/core/loopback-setup.c @@ -61,7 +61,8 @@ static ssize_t sendto_loop(int fd, const void *buf, size_t buf_len, int flags, c for (;;) { ssize_t l; - if ((l = sendto(fd, buf, buf_len, flags, sa, sa_len)) >= 0) + l = sendto(fd, buf, buf_len, flags, sa, sa_len); + if (l >= 0) return l; if (errno != EINTR) @@ -74,7 +75,8 @@ static ssize_t recvfrom_loop(int fd, void *buf, size_t buf_len, int flags, struc for (;;) { ssize_t l; - if ((l = recvfrom(fd, buf, buf_len, flags, sa, sa_len)) >= 0) + l = recvfrom(fd, buf, buf_len, flags, sa, sa_len); + if (l >= 0) return l; if (errno != EINTR) @@ -112,7 +114,8 @@ static int add_adresses(int fd, int if_loopback, unsigned *requests) { ifaddrmsg->ifa_scope = RT_SCOPE_HOST; ifaddrmsg->ifa_index = if_loopback; - if ((r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &ipv4_address, sizeof(ipv4_address))) < 0) + r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &ipv4_address, sizeof(ipv4_address)); + if (r < 0) return r; zero(sa); @@ -131,7 +134,8 @@ static int add_adresses(int fd, int if_loopback, unsigned *requests) { ifaddrmsg->ifa_family = AF_INET6; ifaddrmsg->ifa_prefixlen = 128; - if ((r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &in6addr_loopback, sizeof(in6addr_loopback))) < 0) + r = add_rtattr(&request.header, sizeof(request), IFA_LOCAL, &in6addr_loopback, sizeof(in6addr_loopback)); + if (r < 0) return r; if (sendto_loop(fd, &request, request.header.nlmsg_len, 0, &sa.sa, sizeof(sa)) < 0) @@ -193,7 +197,8 @@ static int read_response(int fd, unsigned requests_max) { socklen_t sa_len = sizeof(sa); struct nlmsgerr *nlmsgerr; - if ((l = recvfrom_loop(fd, &response, sizeof(response), 0, &sa.sa, &sa_len)) < 0) + l = recvfrom_loop(fd, &response, sizeof(response), 0, &sa.sa, &sa_len); + if (l < 0) return -errno; if (sa_len != sizeof(sa.nl) || @@ -217,50 +222,88 @@ static int read_response(int fd, unsigned requests_max) { nlmsgerr = NLMSG_DATA(&response.header); - if (nlmsgerr->error < 0 && nlmsgerr->error != -EEXIST) { - log_warning("Netlink failure for request %i: %s", response.header.nlmsg_seq, strerror(-nlmsgerr->error)); + if (nlmsgerr->error < 0 && nlmsgerr->error != -EEXIST) return nlmsgerr->error; - } return response.header.nlmsg_seq; } +static int check_loopback(void) { + int r, fd; + union { + struct sockaddr sa; + struct sockaddr_in in; + } sa; + + /* If we failed to set up the loop back device, check whether + * it might already be set up */ + + fd = socket(AF_INET, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + zero(sa); + sa.in.sin_family = AF_INET; + sa.in.sin_addr.s_addr = INADDR_LOOPBACK; + + if (bind(fd, &sa.sa, sizeof(sa.in)) >= 0) + r = 1; + else + r = errno == EADDRNOTAVAIL ? 0 : -errno; + + close_nointr_nofail(fd); + + return r; +} + int loopback_setup(void) { int r, if_loopback; union { struct sockaddr sa; struct sockaddr_nl nl; - struct sockaddr_storage storage; } sa; unsigned requests = 0, i; int fd; + bool eperm = false; errno = 0; - if ((if_loopback = (int) if_nametoindex("lo")) <= 0) + if_loopback = (int) if_nametoindex("lo"); + if (if_loopback <= 0) return errno ? -errno : -ENODEV; - if ((fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) < 0) + fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (fd < 0) return -errno; zero(sa); sa.nl.nl_family = AF_NETLINK; - if (bind(fd, &sa.sa, sizeof(sa)) < 0) { r = -errno; goto finish; } - if ((r = add_adresses(fd, if_loopback, &requests)) < 0) + r = add_adresses(fd, if_loopback, &requests); + if (r < 0) goto finish; - if ((r = start_interface(fd, if_loopback, &requests)) < 0) + r = start_interface(fd, if_loopback, &requests); + if (r < 0) goto finish; for (i = 0; i < requests; i++) { - if ((r = read_response(fd, requests)) < 0) + r = read_response(fd, requests); + + if (r == -EPERM) + eperm = true; + else if (r < 0) goto finish; } + if (eperm && check_loopback() < 0) { + r = -EPERM; + goto finish; + } + r = 0; finish: |