nss-myhostname: port to sd-rtnl

This commit is contained in:
Tom Gundersen 2014-04-14 12:46:09 +02:00
parent 6e20c8f8fa
commit d1ca51b153
2 changed files with 109 additions and 170 deletions

View File

@ -4062,6 +4062,10 @@ libnss_myhostname_la_LDFLAGS = \
-shared \
-shrext .so.2
libnss_myhostname_la_LIBADD = \
libsystemd-shared.la \
libsystemd-internal.la
lib_LTLIBRARIES += \
libnss_myhostname.la
endif

View File

@ -4,6 +4,7 @@
This file is part of systemd.
Copyright 2008-2011 Lennart Poettering
Copyright 2014 Tom Gundersen
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
@ -19,188 +20,122 @@
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <sys/socket.h>
#include <sys/un.h>
#include <asm/types.h>
#include <inttypes.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include "sd-rtnl.h"
#include "rtnl-util.h"
#include "macro.h"
#include "ifconf.h"
#define SEQ 4711
static int read_reply(int fd, struct address **list, unsigned *n_list) {
ssize_t bytes;
struct cmsghdr *cmsg;
struct ucred *ucred;
struct nlmsghdr *p;
uint8_t cred_buffer[CMSG_SPACE(sizeof(struct ucred))];
struct {
struct nlmsghdr hdr;
struct ifaddrmsg ifaddrmsg;
uint8_t payload[16*1024];
} resp;
struct iovec iov = {
.iov_base = &resp,
.iov_len = sizeof(resp),
};
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = cred_buffer,
.msg_controllen = sizeof(cred_buffer),
.msg_flags = 0,
};
assert(fd >= 0);
assert(list);
bytes = recvmsg(fd, &msg, 0);
if (bytes < 0)
return -errno;
cmsg = CMSG_FIRSTHDR(&msg);
if (!cmsg || cmsg->cmsg_type != SCM_CREDENTIALS)
return -EIO;
ucred = (struct ucred*) CMSG_DATA(cmsg);
if (ucred->uid != 0 || ucred->pid != 0)
return 0;
for (p = &resp.hdr; bytes > 0; p = NLMSG_NEXT(p, bytes)) {
struct ifaddrmsg *ifaddrmsg;
struct rtattr *a;
size_t l;
void *local = NULL, *address = NULL;
if (!NLMSG_OK(p, (size_t) bytes))
return -EIO;
if (p->nlmsg_seq != SEQ)
continue;
if (p->nlmsg_type == NLMSG_DONE)
return 1;
if (p->nlmsg_type == NLMSG_ERROR) {
struct nlmsgerr *nlmsgerr;
nlmsgerr = NLMSG_DATA(p);
return -nlmsgerr->error;
}
if (p->nlmsg_type != RTM_NEWADDR)
continue;
ifaddrmsg = NLMSG_DATA(p);
if (ifaddrmsg->ifa_family != AF_INET &&
ifaddrmsg->ifa_family != AF_INET6)
continue;
if (ifaddrmsg->ifa_scope == RT_SCOPE_HOST ||
ifaddrmsg->ifa_scope == RT_SCOPE_NOWHERE)
continue;
if (ifaddrmsg->ifa_flags & IFA_F_DEPRECATED)
continue;
l = NLMSG_PAYLOAD(p, sizeof(struct ifaddrmsg));
a = IFA_RTA(ifaddrmsg);
while (RTA_OK(a, l)) {
if (a->rta_type == IFA_ADDRESS)
address = RTA_DATA(a);
else if (a->rta_type == IFA_LOCAL)
local = RTA_DATA(a);
a = RTA_NEXT(a, l);
}
if (local)
address = local;
if (!address)
continue;
*list = realloc(*list, (*n_list+1) * sizeof(struct address));
if (!*list)
return -ENOMEM;
(*list)[*n_list].family = ifaddrmsg->ifa_family;
(*list)[*n_list].scope = ifaddrmsg->ifa_scope;
memcpy((*list)[*n_list].address,
address, ifaddrmsg->ifa_family == AF_INET ? 4 : 16);
(*list)[*n_list].ifindex = ifaddrmsg->ifa_index;
(*n_list)++;
}
return 0;
}
int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) {
struct {
struct nlmsghdr hdr;
struct rtgenmsg gen;
} req = { {
.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
.nlmsg_type = RTM_GETADDR,
.nlmsg_flags = NLM_F_REQUEST|NLM_F_DUMP|NLM_F_ACK,
.nlmsg_seq = SEQ,
.nlmsg_pid = 0,
}, {
.rtgen_family = AF_UNSPEC,
}
};
int r, on = 1;
struct address *list = NULL;
_cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
_cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL;
sd_rtnl_message *m;
_cleanup_free_ struct address *list = NULL;
struct address *new_list = NULL;
unsigned n_list = 0;
int fd;
int r;
fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
if (fd < 0)
return -errno;
if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) {
r = -errno;
goto finish;
}
if (send(fd, &req, req.hdr.nlmsg_len, 0) < 0) {
r = -errno;
goto finish;
}
while((r = read_reply(fd, &list, &n_list)) == 0)
;
finish:
close(fd);
if (r < 0) {
free(list);
r = sd_rtnl_open(&rtnl, 0);
if (r < 0)
return r;
r = sd_rtnl_message_new_addr(rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
if (r < 0)
return r;
r = sd_rtnl_call(rtnl, req, 0, &reply);
if (r < 0)
return r;
m = reply;
do {
uint16_t type;
unsigned char scope;
unsigned char flags;
unsigned char family;
int ifindex;
union {
struct in_addr in;
struct in6_addr in6;
} address;
r = sd_rtnl_message_get_errno(m);
if (r < 0)
return r;
r = sd_rtnl_message_get_type(m, &type);
if (r < 0)
return r;
if (type != RTM_NEWADDR)
continue;
r = sd_rtnl_message_addr_get_scope(m, &scope);
if (r < 0)
return r;
if (scope == RT_SCOPE_HOST || scope == RT_SCOPE_NOWHERE)
continue;
r = sd_rtnl_message_addr_get_flags(m, &flags);
if (r < 0)
return r;
if (flags & IFA_F_DEPRECATED)
continue;
r = sd_rtnl_message_addr_get_family(m, &family);
if (r < 0)
return r;
switch (family) {
case AF_INET:
r = sd_rtnl_message_read_in_addr(m, IFA_LOCAL, &address.in);
if (r < 0) {
r = sd_rtnl_message_read_in_addr(m, IFA_ADDRESS, &address.in);
if (r < 0)
continue;
}
break;
case AF_INET6:
r = sd_rtnl_message_read_in6_addr(m, IFA_LOCAL, &address.in6);
if (r < 0) {
r = sd_rtnl_message_read_in6_addr(m, IFA_ADDRESS, &address.in6);
if (r < 0)
continue;
}
break;
default:
continue;
}
r = sd_rtnl_message_addr_get_ifindex(m, &ifindex);
if (r < 0)
return r;
new_list = realloc(list, (n_list+1) * sizeof(struct address));
if (!new_list)
return -ENOMEM;
else
list = new_list;
assert_cc(sizeof(address) <= 16);
list[n_list].family = family;
list[n_list].scope = scope;
memcpy(list[n_list].address, &address, sizeof(address));
list[n_list].ifindex = ifindex;
n_list++;
} while ((m = sd_rtnl_message_next(m)));
if (n_list)
qsort(list, n_list, sizeof(struct address), address_compare);
*_list = list;
*_n_list = n_list;
*_list = list;
list = NULL;
return 0;
}