systemd/src/shared/import-util.c

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  This file is part of systemd.

  Copyright 2015 Lennart Poettering

  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 "btrfs-util.h"
#include "string-util.h"
#include "util.h"
#include "import-util.h"

int import_url_last_component(const char *url, char **ret) {
        const char *e, *p;
        char *s;

        e = strchrnul(url, '?');

        while (e > url && e[-1] == '/')
                e--;

        p = e;
        while (p > url && p[-1] != '/')
                p--;

        if (e <= p)
                return -EINVAL;

        s = strndup(p, e - p);
        if (!s)
                return -ENOMEM;

        *ret = s;
        return 0;
}


int import_url_change_last_component(const char *url, const char *suffix, char **ret) {
        const char *e;
        char *s;

        assert(url);
        assert(ret);

        e = strchrnul(url, '?');

        while (e > url && e[-1] == '/')
                e--;

        while (e > url && e[-1] != '/')
                e--;

        if (e <= url)
                return -EINVAL;

        s = new(char, (e - url) + strlen(suffix) + 1);
        if (!s)
                return -ENOMEM;

        strcpy(mempcpy(s, url, e - url), suffix);
        *ret = s;
        return 0;
}

static const char* const import_verify_table[_IMPORT_VERIFY_MAX] = {
        [IMPORT_VERIFY_NO] = "no",
        [IMPORT_VERIFY_CHECKSUM] = "checksum",
        [IMPORT_VERIFY_SIGNATURE] = "signature",
};

DEFINE_STRING_TABLE_LOOKUP(import_verify, ImportVerify);

int tar_strip_suffixes(const char *name, char **ret) {
        const char *e;
        char *s;

        e = endswith(name, ".tar");
        if (!e)
                e = endswith(name, ".tar.xz");
        if (!e)
                e = endswith(name, ".tar.gz");
        if (!e)
                e = endswith(name, ".tar.bz2");
        if (!e)
                e = endswith(name, ".tgz");
        if (!e)
                e = strchr(name, 0);

        if (e <= name)
                return -EINVAL;

        s = strndup(name, e - name);
        if (!s)
                return -ENOMEM;

        *ret = s;
        return 0;
}

int raw_strip_suffixes(const char *p, char **ret) {

        static const char suffixes[] =
                ".xz\0"
                ".gz\0"
                ".bz2\0"
                ".raw\0"
                ".qcow2\0"
                ".img\0"
                ".bin\0";

        _cleanup_free_ char *q = NULL;

        q = strdup(p);
        if (!q)
                return -ENOMEM;

        for (;;) {
                const char *sfx;
                bool changed = false;

                NULSTR_FOREACH(sfx, suffixes) {
                        char *e;

                        e = endswith(q, sfx);
                        if (e) {
                                *e = 0;
                                changed = true;
                        }
                }

                if (!changed)
                        break;
        }

        *ret = q;
        q = NULL;

        return 0;
}

bool dkr_digest_is_valid(const char *digest) {
        /* 7 chars for prefix, 64 chars for the digest itself */
        if (strlen(digest) != 71)
                return false;

        return startswith(digest, "sha256:") && in_charset(digest + 7, "0123456789abcdef");
}

bool dkr_ref_is_valid(const char *ref) {
        const char *colon;

        if (isempty(ref))
                return false;

        colon = strchr(ref, ':');
        if (!colon)
                return filename_is_valid(ref);

        return dkr_digest_is_valid(ref);
}

bool dkr_name_is_valid(const char *name) {
        const char *slash, *p;

        if (isempty(name))
                return false;

        slash = strchr(name, '/');
        if (!slash)
                return false;

        if (!filename_is_valid(slash + 1))
                return false;

        p = strndupa(name, slash - name);
        if (!filename_is_valid(p))
                return false;

        return true;
}

bool dkr_id_is_valid(const char *id) {

        if (!filename_is_valid(id))
                return false;

        if (!in_charset(id, "0123456789abcdef"))
                return false;

        return true;
}

int import_assign_pool_quota_and_warn(const char *path) {
        int r;

        r = btrfs_subvol_auto_qgroup("/var/lib/machines", 0, true);
        if (r == -ENOTTY)  {
                log_debug_errno(r, "Failed to set up default quota hierarchy for /var/lib/machines, as directory is not on btrfs or not a subvolume. Ignoring.");
                return 0;
        }
        if (r < 0)
                return log_error_errno(r, "Failed to set up default quota hierarchy for /var/lib/machines: %m");
        if (r > 0)
                log_info("Set up default quota hierarchy for /var/lib/machines.");

        r = btrfs_subvol_auto_qgroup(path, 0, true);
        if (r == -ENOTTY) {
                log_debug_errno(r, "Failed to set up quota hierarchy for %s, as directory is not on btrfs or not a subvolume. Ignoring.", path);
                return 0;
        }
        if (r < 0)
                return log_error_errno(r, "Failed to set up default quota hierarchy for %s: %m", path);
        if (r > 0)
                log_info("Set up default quota hierarchy for %s.", path);

        return 0;
}