chiark / gitweb /
build-sys: move source files to subdirectory
[elogind.git] / src / socket-util.c
diff --git a/src/socket-util.c b/src/socket-util.c
new file mode 100644 (file)
index 0000000..32f6bcb
--- /dev/null
@@ -0,0 +1,468 @@
+/*-*- 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);
+}