import: add a new "pull-gpt" verb for downloading GPT disk images from the internet

Makefile.am

@@ -5136,6 +5136,8 @@ bin_PROGRAMS += \
 
 systemd_import_SOURCES = \
 	src/import/import.c \
+	src/import/import-gpt.c \
+	src/import/import-gpt.h \
 	src/import/import-dkr.c \
 	src/import/import-dkr.h \
 	src/import/curl-util.c \

src/import/curl-util.c

@@ -413,3 +413,34 @@ int curl_header_strdup(const void *contents, size_t sz, const char *field, char
         *value = s;
         return 1;
 }
+
+int curl_parse_http_time(const char *t, time_t *ret) {
+        struct tm tm;
+        time_t v;
+
+        assert(t);
+        assert(ret);
+
+        RUN_WITH_LOCALE(LC_TIME, "C") {
+                const char *e;
+
+                /* RFC822 */
+                e = strptime(t, "%a, %d %b %Y %H:%M:%S %Z", &tm);
+                if (!e || *e != 0)
+                        /* RFC 850 */
+                        e = strptime(t, "%A, %d-%b-%y %H:%M:%S %Z", &tm);
+                if (!e || *e != 0)
+                        /* ANSI C */
+                        e = strptime(t, "%a %b %d %H:%M:%S %Y", &tm);
+                if (!e || *e != 0)
+                        return -EINVAL;
+
+                v = timegm(&tm);
+        }
+
+        if (v == (time_t) -1)
+                return -EINVAL;
+
+        *ret = v;
+        return 0;
+}

src/import/curl-util.h

@@ -51,6 +51,7 @@ void curl_glue_remove_and_free(CurlGlue *g, CURL *c);
 
 struct curl_slist *curl_slist_new(const char *first, ...) _sentinel_;
 int curl_header_strdup(const void *contents, size_t sz, const char *field, char **value);
+int curl_parse_http_time(const char *t, time_t *ret);
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(CURL*, curl_easy_cleanup);
 DEFINE_TRIVIAL_CLEANUP_FUNC(struct curl_slist*, curl_slist_free_all);

src/import/import-gpt.c

@@ -0,0 +1,504 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 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 <sys/xattr.h>
+#include <curl/curl.h>
+
+#include "hashmap.h"
+#include "utf8.h"
+#include "curl-util.h"
+#include "import-gpt.h"
+
+typedef struct GptImportFile GptImportFile;
+
+struct GptImportFile {
+        GptImport *import;
+
+        char *url;
+        char *local;
+
+        CURL *curl;
+        struct curl_slist *request_header;
+
+        char *temp_path;
+        char *final_path;
+        char *etag;
+        char *old_etag;
+
+        uint64_t content_length;
+        uint64_t written;
+
+        time_t mtime;
+
+        bool force_local;
+        bool done;
+
+        int disk_fd;
+};
+
+struct GptImport {
+        sd_event *event;
+        CurlGlue *glue;
+
+        Hashmap *files;
+
+        gpt_import_on_finished on_finished;
+        void *userdata;
+
+        bool finished;
+};
+
+static GptImportFile *gpt_import_file_unref(GptImportFile *f) {
+        if (!f)
+                return NULL;
+
+        if (f->import)
+                curl_glue_remove_and_free(f->import->glue, f->curl);
+        curl_slist_free_all(f->request_header);
+
+        safe_close(f->disk_fd);
+
+        free(f->final_path);
+
+        if (f->temp_path) {
+                unlink(f->temp_path);
+                free(f->temp_path);
+        }
+
+        free(f->url);
+        free(f->local);
+        free(f->etag);
+        free(f->old_etag);
+        free(f);
+
+        return NULL;
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(GptImportFile*, gpt_import_file_unref);
+
+static void gpt_import_finish(GptImport *import, int error) {
+        assert(import);
+
+        if (import->finished)
+                return;
+
+        import->finished = true;
+
+        if (import->on_finished)
+                import->on_finished(import, error, import->userdata);
+        else
+                sd_event_exit(import->event, error);
+}
+
+static void gpt_import_curl_on_finished(CurlGlue *g, CURL *curl, CURLcode result) {
+        GptImportFile *f = NULL;
+        struct stat st;
+        CURLcode code;
+        long status;
+        int r;
+
+        if (curl_easy_getinfo(curl, CURLINFO_PRIVATE, &f) != CURLE_OK)
+                return;
+
+        if (!f)
+                return;
+
+        f->done = true;
+
+        if (result != CURLE_OK) {
+                log_error("Transfer failed: %s", curl_easy_strerror(result));
+                r = -EIO;
+                goto fail;
+        }
+
+        code = curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &status);
+        if (code != CURLE_OK) {
+                log_error("Failed to retrieve response code: %s", curl_easy_strerror(code));
+                r = -EIO;
+                goto fail;
+        } else if (status == 304) {
+                log_info("File unmodified.");
+                r = 0;
+                goto fail;
+        } else if (status >= 300) {
+                log_error("HTTP request to %s failed with code %li.", f->url, status);
+                r = -EIO;
+                goto fail;
+        } else if (status < 200) {
+                log_error("HTTP request to %s finished with unexpected code %li.", f->url, status);
+                r = -EIO;
+                goto fail;
+        }
+
+        if (f->disk_fd < 0) {
+                log_error("No data received.");
+                r = -EIO;
+                goto fail;
+        }
+
+        if (f->content_length != (uint64_t) -1 &&
+            f->content_length != f->written) {
+                log_error("Download truncated.");
+                r = -EIO;
+                goto fail;
+        }
+
+        if (f->etag)
+                (void) fsetxattr(f->disk_fd, "user.etag", f->etag, strlen(f->etag), XATTR_CREATE);
+
+        if (f->mtime != 0) {
+                struct timespec ut[2];
+
+                timespec_store(&ut[0], (usec_t) f->mtime * USEC_PER_SEC);
+                ut[1] = ut[0];
+
+                (void) futimens(f->disk_fd, ut);
+        }
+
+        if (fstat(f->disk_fd, &st) < 0) {
+                r = log_error_errno(errno, "Failed to stat file: %m");
+                goto fail;
+        }
+
+        /* Mark read-only */
+        (void) fchmod(f->disk_fd, st.st_mode & 07444);
+
+        f->disk_fd = safe_close(f->disk_fd);
+
+        assert(f->temp_path);
+        assert(f->final_path);
+
+        r = rename(f->temp_path, f->final_path);
+        if (r < 0) {
+                r = log_error_errno(errno, "Failed to move GPT file into place: %m");
+                goto fail;
+        }
+
+        r = 0;
+
+fail:
+        gpt_import_finish(f->import, r);
+}
+
+static int gpt_import_file_open_disk(GptImportFile *f) {
+        int r;
+
+        assert(f);
+
+        if (f->disk_fd >= 0)
+                return 0;
+
+        assert(f->final_path);
+
+        if (!f->temp_path) {
+                r = tempfn_random(f->final_path, &f->temp_path);
+                if (r < 0)
+                        return log_oom();
+        }
+
+        f->disk_fd = open(f->temp_path, O_CREAT|O_EXCL|O_NOCTTY|O_CLOEXEC|O_WRONLY, 0644);
+        if (f->disk_fd < 0)
+                return log_error_errno(errno, "Failed to create %s: %m", f->temp_path);
+
+        return 0;
+}
+
+static size_t gpt_import_file_write_callback(void *contents, size_t size, size_t nmemb, void *userdata) {
+        GptImportFile *f = userdata;
+        size_t sz = size * nmemb;
+        ssize_t n;
+        int r;
+
+        assert(contents);
+        assert(f);
+
+        r = gpt_import_file_open_disk(f);
+        if (r < 0)
+                goto fail;
+
+        if (f->written + sz < f->written) {
+                log_error("File too large, overflow");
+                r = -EOVERFLOW;
+                goto fail;
+        }
+
+        if (f->content_length != (uint64_t) -1 &&
+            f->written + sz > f->content_length) {
+                log_error("Content length incorrect.");
+                r = -EFBIG;
+                goto fail;
+        }
+
+        n = write(f->disk_fd, contents, sz);
+        if (n < 0) {
+                log_error_errno(errno, "Failed to write file: %m");
+                goto fail;
+        }
+
+        if ((size_t) n < sz) {
+                log_error("Short write");
+                r = -EIO;
+                goto fail;
+        }
+
+        f->written += sz;
+
+        return sz;
+
+fail:
+        gpt_import_finish(f->import, r);
+        return 0;
+}
+
+static size_t gpt_import_file_header_callback(void *contents, size_t size, size_t nmemb, void *userdata) {
+        GptImportFile *f = userdata;
+        size_t sz = size * nmemb;
+        _cleanup_free_ char *length = NULL, *last_modified = NULL;
+        char *etag;
+        int r;
+
+        assert(contents);
+        assert(f);
+
+        r = curl_header_strdup(contents, sz, "ETag:", &etag);
+        if (r < 0) {
+                log_oom();
+                goto fail;
+        }
+        if (r > 0) {
+                free(f->etag);
+                f->etag = etag;
+
+                if (streq_ptr(f->old_etag, f->etag)) {
+                        log_info("Image already up to date. Finishing.");
+                        gpt_import_finish(f->import, 0);
+                        return sz;
+                }
+
+                return sz;
+        }
+
+        r = curl_header_strdup(contents, sz, "Content-Length:", &length);
+        if (r < 0) {
+                log_oom();
+                goto fail;
+        }
+        if (r > 0) {
+                (void) safe_atou64(length, &f->content_length);
+                return sz;
+        }
+
+        r = curl_header_strdup(contents, sz, "Last-Modified:", &last_modified);
+        if (r < 0) {
+                log_oom();
+                goto fail;
+        }
+        if (r > 0) {
+                (void) curl_parse_http_time(last_modified, &f->mtime);
+                return sz;
+        }
+
+        return sz;
+
+fail:
+        gpt_import_finish(f->import, r);
+        return 0;
+}
+
+static int gpt_import_file_begin(GptImportFile *f) {
+        int r;
+
+        assert(f);
+        assert(!f->curl);
+
+        log_info("Getting %s.", f->url);
+
+        r = curl_glue_make(&f->curl, f->url, f);
+        if (r < 0)
+                return r;
+
+        if (f->old_etag) {
+                const char *hdr;
+
+                hdr = strappenda("If-None-Match: ", f->old_etag);
+
+                f->request_header = curl_slist_new(hdr, NULL);
+                if (!f->request_header)
+                        return -ENOMEM;
+
+                if (curl_easy_setopt(f->curl, CURLOPT_HTTPHEADER, f->request_header) != CURLE_OK)
+                        return -EIO;
+        }
+
+        if (curl_easy_setopt(f->curl, CURLOPT_WRITEFUNCTION, gpt_import_file_write_callback) != CURLE_OK)
+                return -EIO;
+
+        if (curl_easy_setopt(f->curl, CURLOPT_WRITEDATA, f) != CURLE_OK)
+                return -EIO;
+
+        if (curl_easy_setopt(f->curl, CURLOPT_HEADERFUNCTION, gpt_import_file_header_callback) != CURLE_OK)
+                return -EIO;
+
+        if (curl_easy_setopt(f->curl, CURLOPT_HEADERDATA, f) != CURLE_OK)
+                return -EIO;
+
+        r = curl_glue_add(f->import->glue, f->curl);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+int gpt_import_new(GptImport **import, sd_event *event, gpt_import_on_finished on_finished, void *userdata) {
+        _cleanup_(gpt_import_unrefp) GptImport *i = NULL;
+        int r;
+
+        assert(import);
+
+        i = new0(GptImport, 1);
+        if (!i)
+                return -ENOMEM;
+
+        i->on_finished = on_finished;
+        i->userdata = userdata;
+
+        if (event)
+                i->event = sd_event_ref(event);
+        else {
+                r = sd_event_default(&i->event);
+                if (r < 0)
+                        return r;
+        }
+
+        r = curl_glue_new(&i->glue, i->event);
+        if (r < 0)
+                return r;
+
+        i->glue->on_finished = gpt_import_curl_on_finished;
+        i->glue->userdata = i;
+
+        *import = i;
+        i = NULL;
+
+        return 0;
+}
+
+GptImport* gpt_import_unref(GptImport *import) {
+        GptImportFile *f;
+
+        if (!import)
+                return NULL;
+
+        while ((f = hashmap_steal_first(import->files)))
+                gpt_import_file_unref(f);
+        hashmap_free(import->files);
+
+        curl_glue_unref(import->glue);
+        sd_event_unref(import->event);
+
+        free(import);
+
+        return NULL;
+}
+
+int gpt_import_cancel(GptImport *import, const char *url) {
+        GptImportFile *f;
+
+        assert(import);
+        assert(url);
+
+        f = hashmap_remove(import->files, url);
+        if (!f)
+                return 0;
+
+        gpt_import_file_unref(f);
+        return 1;
+}
+
+int gpt_import_pull(GptImport *import, const char *url, const char *local, bool force_local) {
+        _cleanup_(gpt_import_file_unrefp) GptImportFile *f = NULL;
+        char etag[LINE_MAX];
+        ssize_t n;
+        int r;
+
+        assert(import);
+        assert(gpt_url_is_valid(url));
+        assert(machine_name_is_valid(local));
+
+        if (hashmap_get(import->files, url))
+                return -EEXIST;
+
+        r = hashmap_ensure_allocated(&import->files, &string_hash_ops);
+        if (r < 0)
+                return r;
+
+        f = new0(GptImportFile, 1);
+        if (!f)
+                return -ENOMEM;
+
+        f->import = import;
+        f->disk_fd = -1;
+        f->content_length = (uint64_t) -1;
+
+        f->url = strdup(url);
+        if (!f->url)
+                return -ENOMEM;
+
+        f->local = strdup(local);
+        if (!f->local)
+                return -ENOMEM;
+
+        f->final_path = strjoin("/var/lib/container/", local, ".gpt", NULL);
+        if (!f->final_path)
+                return -ENOMEM;
+
+        n = getxattr(f->final_path, "user.etag", etag, sizeof(etag));
+        if (n > 0) {
+                f->old_etag = strndup(etag, n);
+                if (!f->old_etag)
+                        return -ENOMEM;
+        }
+
+        r = hashmap_put(import->files, f->url, f);
+        if (r < 0)
+                return r;
+
+        r = gpt_import_file_begin(f);
+        if (r < 0) {
+                gpt_import_cancel(import, f->url);
+                f = NULL;
+                return r;
+        }
+
+        f = NULL;
+        return 0;
+}
+
+bool gpt_url_is_valid(const char *url) {
+        if (isempty(url))
+                return false;
+
+        if (!startswith(url, "http://") &&
+            !startswith(url, "https://"))
+                return false;
+
+        return ascii_is_valid(url);
+}

src/import/import-gpt.h

@@ -0,0 +1,37 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 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 "sd-event.h"
+#include "util.h"
+
+typedef struct GptImport GptImport;
+
+typedef void (*gpt_import_on_finished)(GptImport *import, int error, void *userdata);
+
+int gpt_import_new(GptImport **import, sd_event *event, gpt_import_on_finished on_finished, void *userdata);
+GptImport* gpt_import_unref(GptImport *import);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(GptImport*, gpt_import_unref);
+
+int gpt_import_pull(GptImport *import, const char *url, const char *local, bool force_local);
+int gpt_import_cancel(GptImport *import, const char *name);
+
+bool gpt_url_is_valid(const char *url);

src/import/import.c

@@ -25,13 +25,103 @@
 #include "event-util.h"
 #include "verbs.h"
 #include "build.h"
+#include "import-gpt.h"
 #include "import-dkr.h"
 
 static bool arg_force = false;
 
 static const char* arg_dkr_index_url = DEFAULT_DKR_INDEX_URL;
 
-static void on_finished(DkrImport *import, int error, void *userdata) {
+static void on_gpt_finished(GptImport *import, int error, void *userdata) {
+        sd_event *event = userdata;
+        assert(import);
+
+        if (error == 0)
+                log_info("Operation completed successfully.");
+        else
+                log_info_errno(error, "Operation failed: %m");
+
+        sd_event_exit(event, error);
+}
+
+static int pull_gpt(int argc, char *argv[], void *userdata) {
+        _cleanup_(gpt_import_unrefp) GptImport *import = NULL;
+        _cleanup_event_unref_ sd_event *event = NULL;
+        _cleanup_free_ char *local_truncated = NULL, *local_generated = NULL;
+        const char *url, *local, *suffix;
+        int r;
+
+        url = argv[1];
+        local = argv[2];
+
+        if (!gpt_url_is_valid(url)) {
+                log_error("URL '%s' is not valid.", url);
+                return -EINVAL;
+        }
+
+        if (isempty(local) || streq(local, "-"))
+                local = NULL;
+
+        if (!local) {
+                const char *e, *p;
+
+                e = url + strlen(url);
+                while (e > url && e[-1] == '/')
+                        e--;
+
+                p = e;
+                while (p > url && p[-1] != '/')
+                        p--;
+
+                local_generated = strndup(p, e - p);
+                if (!local_generated)
+                        return log_oom();
+
+                local = local_generated;
+        }
+
+        suffix = endswith(local, ".gpt");
+        if (suffix) {
+                local_truncated = strndup(local, suffix - local);
+                if (!local_truncated)
+                        return log_oom();
+
+                local = local_truncated;
+        }
+
+        if (!machine_name_is_valid(local)) {
+                log_error("Local image name '%s' is not valid.", local);
+                return -EINVAL;
+        }
+
+        log_info("Pulling '%s' as '%s'", url, local);
+
+        r = sd_event_default(&event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate event loop: %m");
+
+        assert_se(sigprocmask_many(SIG_BLOCK, SIGTERM, SIGINT, -1) == 0);
+        sd_event_add_signal(event, NULL, SIGTERM, NULL,  NULL);
+        sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+
+        r = gpt_import_new(&import, event, on_gpt_finished, event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate importer: %m");
+
+        r = gpt_import_pull(import, url, local, arg_force);
+        if (r < 0)
+                return log_error_errno(r, "Failed to pull image: %m");
+
+        r = sd_event_loop(event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to run event loop: %m");
+
+        log_info("Exiting.");
+
+        return 0;
+}
+
+static void on_dkr_finished(DkrImport *import, int error, void *userdata) {
         sd_event *event = userdata;
         assert(import);
 
@@ -141,7 +231,8 @@ static int help(int argc, char *argv[], void *userdata) {
                "     --force                  Force creation of image\n"
                "     --dkr-index-url=URL      Specify index URL to use for downloads\n\n"
                "Commands:\n"
-               "  pull-dkr REMOTE [NAME]      Download an image\n",
+               "  pull-dkr REMOTE [NAME]      Download a DKR image\n"
+               "  pull-gpt URL [NAME]         Download a GPT image\n",
                program_invocation_short_name);
 
         return 0;
@@ -208,6 +299,7 @@ static int import_main(int argc, char *argv[]) {
         static const Verb verbs[] = {
                 { "help",     VERB_ANY, VERB_ANY, 0, help     },
                 { "pull-dkr", 2,        3,        0, pull_dkr },
+                { "pull-gpt", 2,        3,        0, pull_gpt },
                 {}
         };