util: move all to shared/ and split external dependencies in separate internal libraries

Before:
  $ ldd /lib/systemd/systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fffb05ff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f90aac57000)
  libcap.so.2 => /lib64/libcap.so.2 (0x00007f90aaa53000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f90aa84a000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f90aa494000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f90aae90000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f90aa290000)
  libattr.so.1 => /lib64/libattr.so.1 (0x00007f90aa08a000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f90a9e6e000)

After:
  $ ldd systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fff3cbff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f5eaa1c3000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f5ea9fbb000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f5ea9c04000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f5eaa3fc000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f5ea9a00000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f5ea97e4000)

1 files changed, 652 insertions, 0 deletions

diff --git a/src/shared/socket-util.c b/src/shared/socket-util.c
new file mode 100644
index 000000000..acc4d3337
--- /dev/null
+++ b/src/shared/socket-util.c
@@ -0,0 +1,652 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  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 <stddef.h>
+#include <sys/ioctl.h>
+
+#include "macro.h"
+#include "util.h"
+#include "socket-util.h"
+#include "missing.h"
+#include "label.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 (!socket_ipv6_is_supported()) {
+                        log_warning("Binding to IPv6 address not available since kernel does not support IPv6.");
+                        return -EAFNOSUPPORT;
+                }
+
+                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 = offsetof(struct sockaddr_un, sun_path) + 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 = offsetof(struct sockaddr_un, sun_path) + 1 + l;
+
+        } 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;
+
+                                if (!socket_ipv6_is_supported()) {
+                                        log_warning("Binding to interface is not available since kernel does not support IPv6.");
+                                        return -EAFNOSUPPORT;
+                                }
+
+                                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;
+
+                        if (socket_ipv6_is_supported()) {
+                                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);
+                        } else {
+                                a->sockaddr.in4.sin_family = AF_INET;
+                                a->sockaddr.in4.sin_port = htons((uint16_t) u);
+                                a->sockaddr.in4.sin_addr.s_addr = INADDR_ANY;
+                                a->size = sizeof(struct sockaddr_in);
+                        }
+                }
+        }
+
+        return 0;
+}
+
+int socket_address_parse_netlink(SocketAddress *a, const char *s) {
+        int family;
+        unsigned group = 0;
+        char* sfamily = NULL;
+        assert(a);
+        assert(s);
+
+        zero(*a);
+        a->type = SOCK_RAW;
+
+        errno = 0;
+        if (sscanf(s, "%ms %u", &sfamily, &group) < 1)
+                return errno ? -errno : -EINVAL;
+
+        if ((family = netlink_family_from_string(sfamily)) < 0)
+                if (safe_atoi(sfamily, &family) < 0) {
+                        free(sfamily);
+                        return -EINVAL;
+                }
+
+        free(sfamily);
+
+        a->sockaddr.nl.nl_family = AF_NETLINK;
+        a->sockaddr.nl.nl_groups = group;
+
+        a->type = SOCK_RAW;
+        a->size = sizeof(struct sockaddr_nl);
+        a->protocol = family;
+
+        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;
+
+                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+                        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;
+
+                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+                        return -EINVAL;
+
+                return 0;
+
+        case AF_UNIX:
+                if (a->size < offsetof(struct sockaddr_un, sun_path))
+                        return -EINVAL;
+
+                if (a->size > offsetof(struct sockaddr_un, sun_path)) {
+
+                        if (a->sockaddr.un.sun_path[0] != 0) {
+                                char *e;
+
+                                /* path */
+                                if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path))))
+                                        return -EINVAL;
+
+                                if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
+                                        return -EINVAL;
+                        }
+                }
+
+                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type != SOCK_SEQPACKET)
+                        return -EINVAL;
+
+                return 0;
+
+        case AF_NETLINK:
+
+                if (a->size != sizeof(struct sockaddr_nl))
+                        return -EINVAL;
+
+                if (a->type != SOCK_RAW && a->type != SOCK_DGRAM)
+                        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 <= offsetof(struct sockaddr_un, sun_path)) {
+
+                        if (!(ret = strdup("<unnamed>")))
+                                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;
+        }
+
+        case AF_NETLINK: {
+                const char *sfamily;
+
+                if ((sfamily = netlink_family_to_string(a->protocol)))
+                        r = asprintf(p, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
+                else
+                        r = asprintf(p, "%i %u", a->protocol, a->sockaddr.nl.nl_groups);
+
+                if (r < 0)
+                        return -ENOMEM;
+
+                return 0;
+        }
+
+        default:
+                return -EINVAL;
+        }
+}
+
+int socket_address_listen(
+                const SocketAddress *a,
+                int backlog,
+                SocketAddressBindIPv6Only only,
+                const char *bind_to_device,
+                bool free_bind,
+                bool transparent,
+                mode_t directory_mode,
+                mode_t socket_mode,
+                const char *label,
+                int *ret) {
+
+        int r, fd, one;
+        assert(a);
+        assert(ret);
+
+        if ((r = socket_address_verify(a)) < 0)
+                return r;
+
+        if (socket_address_family(a) == AF_INET6 && !socket_ipv6_is_supported())
+                return -EAFNOSUPPORT;
+
+        r = label_socket_set(label);
+        if (r < 0)
+                return r;
+
+        fd = socket(socket_address_family(a), a->type | SOCK_NONBLOCK | SOCK_CLOEXEC, a->protocol);
+        r = fd < 0 ? -errno : 0;
+
+        label_socket_clear();
+
+        if (r < 0)
+                return r;
+
+        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 (socket_address_family(a) == AF_INET || socket_address_family(a) == AF_INET6) {
+                if (bind_to_device)
+                        if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, bind_to_device, strlen(bind_to_device)+1) < 0)
+                                goto fail;
+
+                if (free_bind) {
+                        one = 1;
+                        if (setsockopt(fd, IPPROTO_IP, IP_FREEBIND, &one, sizeof(one)) < 0)
+                                log_warning("IP_FREEBIND failed: %m");
+                }
+
+                if (transparent) {
+                        one = 1;
+                        if (setsockopt(fd, IPPROTO_IP, IP_TRANSPARENT, &one, sizeof(one)) < 0)
+                                log_warning("IP_TRANSPARENT failed: %m");
+                }
+        }
+
+        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 = label_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 (socket_address_can_accept(a))
+                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, a->size) != 0)
+                                return false;
+                }
+
+                break;
+
+        case AF_NETLINK:
+
+                if (a->protocol != b->protocol)
+                        return false;
+
+                if (a->sockaddr.nl.nl_groups != b->sockaddr.nl.nl_groups)
+                        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, int type) {
+        struct SocketAddress b;
+
+        assert(a);
+        assert(s);
+
+        if (socket_address_parse(&b, s) < 0)
+                return false;
+
+        b.type = type;
+
+        return socket_address_equal(a, &b);
+}
+
+bool socket_address_is_netlink(const SocketAddress *a, const char *s) {
+        struct SocketAddress b;
+
+        assert(a);
+        assert(s);
+
+        if (socket_address_parse_netlink(&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);
+}
+
+bool socket_ipv6_is_supported(void) {
+        char *l = 0;
+        bool enabled;
+
+        if (access("/sys/module/ipv6", F_OK) != 0)
+                return 0;
+
+        /* If we can't check "disable" parameter, assume enabled */
+        if (read_one_line_file("/sys/module/ipv6/parameters/disable", &l) < 0)
+                return 1;
+
+        /* If module was loaded with disable=1 no IPv6 available */
+        enabled = l[0] == '0';
+        free(l);
+
+        return enabled;
+}
+
+static const char* const netlink_family_table[] = {
+        [NETLINK_ROUTE] = "route",
+        [NETLINK_FIREWALL] = "firewall",
+        [NETLINK_INET_DIAG] = "inet-diag",
+        [NETLINK_NFLOG] = "nflog",
+        [NETLINK_XFRM] = "xfrm",
+        [NETLINK_SELINUX] = "selinux",
+        [NETLINK_ISCSI] = "iscsi",
+        [NETLINK_AUDIT] = "audit",
+        [NETLINK_FIB_LOOKUP] = "fib-lookup",
+        [NETLINK_CONNECTOR] = "connector",
+        [NETLINK_NETFILTER] = "netfilter",
+        [NETLINK_IP6_FW] = "ip6-fw",
+        [NETLINK_DNRTMSG] = "dnrtmsg",
+        [NETLINK_KOBJECT_UEVENT] = "kobject-uevent",
+        [NETLINK_GENERIC] = "generic",
+        [NETLINK_SCSITRANSPORT] = "scsitransport",
+        [NETLINK_ECRYPTFS] = "ecryptfs"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(netlink_family, int);
+
+static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX] = {
+        [SOCKET_ADDRESS_DEFAULT] = "default",
+        [SOCKET_ADDRESS_BOTH] = "both",
+        [SOCKET_ADDRESS_IPV6_ONLY] = "ipv6-only"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(socket_address_bind_ipv6_only, SocketAddressBindIPv6Only);