sd-network: add new library

This is similar to sd-login, but exposes the state of networkd rather than logind.

Include it in libsystemd-dhcp and rename it to libsystemd-network.

1 files changed, 401 insertions, 0 deletions

diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c
new file mode 100644
index 0000000000..0529b6d8fa
--- /dev/null
+++ b/src/libsystemd-network/sd-dhcp-lease.c
@@ -0,0 +1,401 @@
+/***
+  This file is part of systemd.
+
+  Copyright (C) 2013 Intel Corporation. All rights reserved.
+  Copyright (C) 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
+  the Free Software Foundation; either version 2.1 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <net/ethernet.h>
+#include <arpa/inet.h>
+#include <sys/param.h>
+
+#include "util.h"
+#include "list.h"
+#include "mkdir.h"
+#include "fileio.h"
+
+#include "dhcp-protocol.h"
+#include "dhcp-internal.h"
+#include "dhcp-lease-internal.h"
+#include "sd-dhcp-lease.h"
+#include "sd-dhcp-client.h"
+
+int sd_dhcp_lease_get_address(sd_dhcp_lease *lease, struct in_addr *addr) {
+        assert_return(lease, -EINVAL);
+        assert_return(addr, -EINVAL);
+
+        addr->s_addr = lease->address;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_mtu(sd_dhcp_lease *lease, uint16_t *mtu) {
+        assert_return(lease, -EINVAL);
+        assert_return(mtu, -EINVAL);
+
+        if (lease->mtu)
+                *mtu = lease->mtu;
+        else
+                return -ENOENT;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, struct in_addr **addr, size_t *addr_size) {
+        assert_return(lease, -EINVAL);
+        assert_return(addr, -EINVAL);
+        assert_return(addr_size, -EINVAL);
+
+        if (lease->dns_size) {
+                *addr_size = lease->dns_size;
+                *addr = lease->dns;
+        } else
+                return -ENOENT;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_domainname(sd_dhcp_lease *lease, const char **domainname) {
+        assert_return(lease, -EINVAL);
+        assert_return(domainname, -EINVAL);
+
+        if (lease->domainname)
+                *domainname = lease->domainname;
+        else
+                return -ENOENT;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_hostname(sd_dhcp_lease *lease, const char **hostname) {
+        assert_return(lease, -EINVAL);
+        assert_return(hostname, -EINVAL);
+
+        if (lease->hostname)
+                *hostname = lease->hostname;
+        else
+                return -ENOENT;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, struct in_addr *addr) {
+        assert_return(lease, -EINVAL);
+        assert_return(addr, -EINVAL);
+
+        addr->s_addr = lease->router;
+
+        return 0;
+}
+
+int sd_dhcp_lease_get_netmask(sd_dhcp_lease *lease, struct in_addr *addr) {
+        assert_return(lease, -EINVAL);
+        assert_return(addr, -EINVAL);
+
+        addr->s_addr = lease->subnet_mask;
+
+        return 0;
+}
+
+sd_dhcp_lease *sd_dhcp_lease_ref(sd_dhcp_lease *lease) {
+        if (lease)
+                assert_se(REFCNT_INC(lease->n_ref) >= 2);
+
+        return lease;
+}
+
+sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) {
+        if (lease && REFCNT_DEC(lease->n_ref) <= 0) {
+                free(lease->hostname);
+                free(lease->domainname);
+                free(lease->dns);
+                free(lease);
+        }
+
+        return NULL;
+}
+
+int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option,
+                              void *user_data) {
+        sd_dhcp_lease *lease = user_data;
+        be32_t val;
+
+        switch(code) {
+
+        case DHCP_OPTION_IP_ADDRESS_LEASE_TIME:
+                if (len == 4) {
+                        memcpy(&val, option, 4);
+                        lease->lifetime = be32toh(val);
+                }
+
+                break;
+
+        case DHCP_OPTION_SERVER_IDENTIFIER:
+                if (len >= 4)
+                        memcpy(&lease->server_address, option, 4);
+
+                break;
+
+        case DHCP_OPTION_SUBNET_MASK:
+                if (len >= 4)
+                        memcpy(&lease->subnet_mask, option, 4);
+
+                break;
+
+        case DHCP_OPTION_ROUTER:
+                if (len >= 4)
+                        memcpy(&lease->router, option, 4);
+
+                break;
+
+        case DHCP_OPTION_DOMAIN_NAME_SERVER:
+                if (len && !(len % 4)) {
+                        unsigned i;
+
+                        lease->dns_size = len / 4;
+
+                        free(lease->dns);
+                        lease->dns = new0(struct in_addr, lease->dns_size);
+                        if (!lease->dns)
+                                return -ENOMEM;
+
+                        for (i = 0; i < lease->dns_size; i++) {
+                                memcpy(&lease->dns[i].s_addr, option + 4 * i, 4);
+                        }
+                }
+
+                break;
+
+        case DHCP_OPTION_INTERFACE_MTU:
+                if (len >= 2) {
+                        be16_t mtu;
+
+                        memcpy(&mtu, option, 2);
+                        lease->mtu = be16toh(mtu);
+
+                        if (lease->mtu < 68)
+                                lease->mtu = 0;
+                }
+
+                break;
+
+        case DHCP_OPTION_DOMAIN_NAME:
+                if (len >= 1) {
+                        free(lease->domainname);
+                        lease->domainname = strndup((const char *)option, len);
+                }
+
+                break;
+
+        case DHCP_OPTION_HOST_NAME:
+                if (len >= 1) {
+                        free(lease->hostname);
+                        lease->hostname = strndup((const char *)option, len);
+                }
+
+                break;
+
+        case DHCP_OPTION_RENEWAL_T1_TIME:
+                if (len == 4) {
+                        memcpy(&val, option, 4);
+                        lease->t1 = be32toh(val);
+                }
+
+                break;
+
+        case DHCP_OPTION_REBINDING_T2_TIME:
+                if (len == 4) {
+                        memcpy(&val, option, 4);
+                        lease->t2 = be32toh(val);
+                }
+
+                break;
+        }
+
+        return 0;
+}
+
+int dhcp_lease_new(sd_dhcp_lease **ret) {
+        _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
+
+        lease = new0(sd_dhcp_lease, 1);
+        if (!lease)
+                return -ENOMEM;
+
+        lease->n_ref = REFCNT_INIT;
+
+        *ret = lease;
+        lease = NULL;
+
+        return 0;
+}
+
+int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
+        _cleanup_free_ char *temp_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        char buf[INET_ADDRSTRLEN];
+        struct in_addr address;
+        const char *string;
+        uint16_t mtu;
+        int r;
+
+        assert(lease);
+        assert(lease_file);
+
+        r = mkdir_safe_label("/run/systemd/network/leases", 0755, 0, 0);
+        if (r < 0)
+                goto finish;
+
+        r = fopen_temporary(lease_file, &f, &temp_path);
+        if (r < 0)
+                goto finish;
+
+        fchmod(fileno(f), 0644);
+
+        r = sd_dhcp_lease_get_address(lease, &address);
+        if (r < 0)
+                goto finish;
+
+        string = inet_ntop(AF_INET, &address, buf, INET_ADDRSTRLEN);
+        if (!string) {
+                r = -errno;
+                goto finish;
+        }
+
+        fprintf(f,
+                "# This is private data. Do not parse.\n"
+                "ADDRESS=%s\n", string);
+
+        r = sd_dhcp_lease_get_router(lease, &address);
+        if (r < 0)
+                goto finish;
+
+        string = inet_ntop(AF_INET, &address, buf, INET_ADDRSTRLEN);
+        if (!string) {
+                r = -errno;
+                goto finish;
+        }
+
+        fprintf(f,
+                "ROUTER=%s\n", string);
+
+        r = sd_dhcp_lease_get_netmask(lease, &address);
+        if (r < 0)
+                goto finish;
+
+        string = inet_ntop(AF_INET, &address, buf, INET_ADDRSTRLEN);
+        if (!string) {
+                r = -errno;
+                goto finish;
+        }
+
+        fprintf(f,
+                "NETMASK=%s\n", string);
+
+        r = sd_dhcp_lease_get_mtu(lease, &mtu);
+        if (r >= 0)
+                fprintf(f, "MTU=%" PRIu16 "\n", mtu);
+
+/* TODO: DNS. See resolv.conf writing in network-manager.c */
+
+        r = sd_dhcp_lease_get_domainname(lease, &string);
+        if (r >= 0)
+                fprintf(f, "DOMAINNAME=%s\n", string);
+
+        r = sd_dhcp_lease_get_hostname(lease, &string);
+        if (r >= 0)
+                fprintf(f, "HOSTNAME=%s\n", string);
+
+        r = 0;
+
+        fflush(f);
+
+        if (ferror(f) || rename(temp_path, lease_file) < 0) {
+                r = -errno;
+                unlink(lease_file);
+                unlink(temp_path);
+        }
+
+finish:
+        if (r < 0)
+                log_error("Failed to save lease data %s: %s", lease_file, strerror(-r));
+
+        return r;
+}
+
+int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) {
+        _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
+        _cleanup_free_ char *address = NULL, *router = NULL, *netmask = NULL,
+                            *mtu = NULL;
+        struct in_addr addr;
+        int r;
+
+        assert(lease_file);
+        assert(ret);
+
+        r = dhcp_lease_new(&lease);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(lease_file, NEWLINE,
+                           "ADDRESS", &address,
+                           "ROUTER", &router,
+                           "NETMASK", &netmask,
+                           "MTU", &mtu,
+                           "DOMAINNAME", &lease->domainname,
+                           "HOSTNAME", &lease->hostname,
+                           NULL);
+        if (r < 0) {
+                if (r == -ENOENT)
+                        return 0;
+
+                log_error("Failed to read %s: %s", lease_file, strerror(-r));
+                return r;
+        }
+
+        r = inet_pton(AF_INET, address, &addr);
+        if (r < 0)
+                return r;
+
+        lease->address = addr.s_addr;
+
+        r = inet_pton(AF_INET, router, &addr);
+        if (r < 0)
+                return r;
+
+        lease->router = addr.s_addr;
+
+        r = inet_pton(AF_INET, netmask, &addr);
+        if (r < 0)
+                return r;
+
+        lease->subnet_mask = addr.s_addr;
+
+        if (mtu) {
+                uint16_t u;
+                if (sscanf(mtu, "%" SCNu16, &u) > 0)
+                        lease->mtu = u;
+        }
+
+        *ret = lease;
+        lease = NULL;
+
+        return 0;
+}