eudev/socket-util.c

469 lines
15 KiB
C

/*-*- Mode: C; c-basic-offset: 8 -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <assert.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <net/if.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "macro.h"
#include "util.h"
#include "socket-util.h"
int socket_address_parse(SocketAddress *a, const char *s) {
int r;
char *e, *n;
unsigned u;
assert(a);
assert(s);
zero(*a);
a->type = SOCK_STREAM;
if (*s == '[') {
/* IPv6 in [x:.....:z]:p notation */
if (!(e = strchr(s+1, ']')))
return -EINVAL;
if (!(n = strndup(s+1, e-s-1)))
return -ENOMEM;
errno = 0;
if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0) {
free(n);
return errno != 0 ? -errno : -EINVAL;
}
free(n);
e++;
if (*e != ':')
return -EINVAL;
e++;
if ((r = safe_atou(e, &u)) < 0)
return r;
if (u <= 0 || u > 0xFFFF)
return -EINVAL;
a->sockaddr.in6.sin6_family = AF_INET6;
a->sockaddr.in6.sin6_port = htons((uint16_t) u);
a->size = sizeof(struct sockaddr_in6);
} else if (*s == '/') {
/* AF_UNIX socket */
size_t l;
l = strlen(s);
if (l >= sizeof(a->sockaddr.un.sun_path))
return -EINVAL;
a->sockaddr.un.sun_family = AF_UNIX;
memcpy(a->sockaddr.un.sun_path, s, l);
a->size = sizeof(sa_family_t) + l + 1;
} else if (*s == '@') {
/* Abstract AF_UNIX socket */
size_t l;
l = strlen(s+1);
if (l >= sizeof(a->sockaddr.un.sun_path) - 1)
return -EINVAL;
a->sockaddr.un.sun_family = AF_UNIX;
memcpy(a->sockaddr.un.sun_path+1, s+1, l);
a->size = sizeof(struct sockaddr_un);
} else {
if ((e = strchr(s, ':'))) {
if ((r = safe_atou(e+1, &u)) < 0)
return r;
if (u <= 0 || u > 0xFFFF)
return -EINVAL;
if (!(n = strndup(s, e-s)))
return -ENOMEM;
/* IPv4 in w.x.y.z:p notation? */
if ((r = inet_pton(AF_INET, n, &a->sockaddr.in4.sin_addr)) < 0) {
free(n);
return -errno;
}
if (r > 0) {
/* Gotcha, it's a traditional IPv4 address */
free(n);
a->sockaddr.in4.sin_family = AF_INET;
a->sockaddr.in4.sin_port = htons((uint16_t) u);
a->size = sizeof(struct sockaddr_in);
} else {
unsigned idx;
if (strlen(n) > IF_NAMESIZE-1) {
free(n);
return -EINVAL;
}
/* Uh, our last resort, an interface name */
idx = if_nametoindex(n);
free(n);
if (idx == 0)
return -EINVAL;
a->sockaddr.in6.sin6_family = AF_INET6;
a->sockaddr.in6.sin6_port = htons((uint16_t) u);
a->sockaddr.in6.sin6_scope_id = idx;
a->sockaddr.in6.sin6_addr = in6addr_any;
a->size = sizeof(struct sockaddr_in6);
}
} else {
/* Just a port */
if ((r = safe_atou(s, &u)) < 0)
return r;
if (u <= 0 || u > 0xFFFF)
return -EINVAL;
a->sockaddr.in6.sin6_family = AF_INET6;
a->sockaddr.in6.sin6_port = htons((uint16_t) u);
a->sockaddr.in6.sin6_addr = in6addr_any;
a->size = sizeof(struct sockaddr_in6);
}
}
return 0;
}
int socket_address_verify(const SocketAddress *a) {
assert(a);
switch (socket_address_family(a)) {
case AF_INET:
if (a->size != sizeof(struct sockaddr_in))
return -EINVAL;
if (a->sockaddr.in4.sin_port == 0)
return -EINVAL;
return 0;
case AF_INET6:
if (a->size != sizeof(struct sockaddr_in6))
return -EINVAL;
if (a->sockaddr.in6.sin6_port == 0)
return -EINVAL;
return 0;
case AF_UNIX:
if (a->size < sizeof(sa_family_t))
return -EINVAL;
if (a->size > sizeof(sa_family_t)) {
if (a->sockaddr.un.sun_path[0] == 0) {
/* abstract */
if (a->size != sizeof(struct sockaddr_un))
return -EINVAL;
} else {
char *e;
/* path */
if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path))))
return -EINVAL;
if (a->size != sizeof(sa_family_t) + (e - a->sockaddr.un.sun_path) + 1)
return -EINVAL;
}
}
return 0;
default:
return -EAFNOSUPPORT;
}
}
int socket_address_print(const SocketAddress *a, char **p) {
int r;
assert(a);
assert(p);
if ((r = socket_address_verify(a)) < 0)
return r;
switch (socket_address_family(a)) {
case AF_INET: {
char *ret;
if (!(ret = new(char, INET_ADDRSTRLEN+1+5+1)))
return -ENOMEM;
if (!inet_ntop(AF_INET, &a->sockaddr.in4.sin_addr, ret, INET_ADDRSTRLEN)) {
free(ret);
return -errno;
}
sprintf(strchr(ret, 0), ":%u", ntohs(a->sockaddr.in4.sin_port));
*p = ret;
return 0;
}
case AF_INET6: {
char *ret;
if (!(ret = new(char, 1+INET6_ADDRSTRLEN+2+5+1)))
return -ENOMEM;
ret[0] = '[';
if (!inet_ntop(AF_INET6, &a->sockaddr.in6.sin6_addr, ret+1, INET6_ADDRSTRLEN)) {
free(ret);
return -errno;
}
sprintf(strchr(ret, 0), "]:%u", ntohs(a->sockaddr.in6.sin6_port));
*p = ret;
return 0;
}
case AF_UNIX: {
char *ret;
if (a->size <= sizeof(sa_family_t)) {
if (!(ret = strdup("<unamed>")))
return -ENOMEM;
} else if (a->sockaddr.un.sun_path[0] == 0) {
/* abstract */
/* FIXME: We assume we can print the
* socket path here and that it hasn't
* more than one NUL byte. That is
* actually an invalid assumption */
if (!(ret = new(char, sizeof(a->sockaddr.un.sun_path)+1)))
return -ENOMEM;
ret[0] = '@';
memcpy(ret+1, a->sockaddr.un.sun_path+1, sizeof(a->sockaddr.un.sun_path)-1);
ret[sizeof(a->sockaddr.un.sun_path)] = 0;
} else {
if (!(ret = strdup(a->sockaddr.un.sun_path)))
return -ENOMEM;
}
*p = ret;
return 0;
}
default:
return -EINVAL;
}
}
int socket_address_listen(
const SocketAddress *a,
int backlog,
SocketAddressBindIPv6Only only,
const char *bind_to_device,
mode_t directory_mode,
mode_t socket_mode,
int *ret) {
int r, fd, one;
assert(a);
assert(ret);
if ((r = socket_address_verify(a)) < 0)
return r;
if ((fd = socket(socket_address_family(a), a->type | SOCK_NONBLOCK | SOCK_CLOEXEC, 0)) < 0)
return -errno;
if (socket_address_family(a) == AF_INET6 && only != SOCKET_ADDRESS_DEFAULT) {
int flag = only == SOCKET_ADDRESS_IPV6_ONLY;
if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &flag, sizeof(flag)) < 0)
goto fail;
}
if (bind_to_device)
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, bind_to_device, strlen(bind_to_device)+1) < 0)
goto fail;
one = 1;
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0)
goto fail;
if (socket_address_family(a) == AF_UNIX && a->sockaddr.un.sun_path[0] != 0) {
mode_t old_mask;
/* Create parents */
mkdir_parents(a->sockaddr.un.sun_path, directory_mode);
/* Enforce the right access mode for the socket*/
old_mask = umask(~ socket_mode);
/* Include the original umask in our mask */
umask(~socket_mode | old_mask);
r = bind(fd, &a->sockaddr.sa, a->size);
if (r < 0 && errno == EADDRINUSE) {
/* Unlink and try again */
unlink(a->sockaddr.un.sun_path);
r = bind(fd, &a->sockaddr.sa, a->size);
}
umask(old_mask);
} else
r = bind(fd, &a->sockaddr.sa, a->size);
if (r < 0)
goto fail;
if (a->type == SOCK_STREAM)
if (listen(fd, backlog) < 0)
goto fail;
*ret = fd;
return 0;
fail:
r = -errno;
close_nointr_nofail(fd);
return r;
}
bool socket_address_can_accept(const SocketAddress *a) {
assert(a);
return
a->type == SOCK_STREAM ||
a->type == SOCK_SEQPACKET;
}
bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
assert(a);
assert(b);
/* Invalid addresses are unequal to all */
if (socket_address_verify(a) < 0 ||
socket_address_verify(b) < 0)
return false;
if (a->type != b->type)
return false;
if (a->size != b->size)
return false;
if (socket_address_family(a) != socket_address_family(b))
return false;
switch (socket_address_family(a)) {
case AF_INET:
if (a->sockaddr.in4.sin_addr.s_addr != b->sockaddr.in4.sin_addr.s_addr)
return false;
if (a->sockaddr.in4.sin_port != b->sockaddr.in4.sin_port)
return false;
break;
case AF_INET6:
if (memcmp(&a->sockaddr.in6.sin6_addr, &b->sockaddr.in6.sin6_addr, sizeof(a->sockaddr.in6.sin6_addr)) != 0)
return false;
if (a->sockaddr.in6.sin6_port != b->sockaddr.in6.sin6_port)
return false;
break;
case AF_UNIX:
if ((a->sockaddr.un.sun_path[0] == 0) != (b->sockaddr.un.sun_path[0] == 0))
return false;
if (a->sockaddr.un.sun_path[0]) {
if (strncmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path)) != 0)
return false;
} else {
if (memcmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path)) != 0)
return false;
}
break;
default:
/* Cannot compare, so we assume the addresses are different */
return false;
}
return true;
}
bool socket_address_is(const SocketAddress *a, const char *s) {
struct SocketAddress b;
assert(a);
assert(s);
if (socket_address_parse(&b, s) < 0)
return false;
return socket_address_equal(a, &b);
}
bool socket_address_needs_mount(const SocketAddress *a, const char *prefix) {
assert(a);
if (socket_address_family(a) != AF_UNIX)
return false;
if (a->sockaddr.un.sun_path[0] == 0)
return false;
return path_startswith(a->sockaddr.un.sun_path, prefix);
}