#include <fcntl.h>

#include <sys/stat.h>

#include <sys/xattr.h>

#include "alloc-util.h"

#include "fd-util.h"

#include "format-util.h"

#include "gcrypt-util.h"

#include "hexdecoct.h"

#include "import-util.h"

#include "io-util.h"

#include "machine-pool.h"

#include "parse-util.h"

#include "pull-common.h"

#include "pull-job.h"

#include "string-util.h"

#include "strv.h"

#include "sync-util.h"

#include "xattr-util.h"

void pull_job_close_disk_fd(PullJob *j) {

if (!j)

return;

if (j->close_disk_fd)

safe_close(j->disk_fd);

j->disk_fd = -1;

}

PullJob* pull_job_unref(PullJob *j) {

if (!j)

return NULL;

pull_job_close_disk_fd(j);

curl_glue_remove_and_free(j->glue, j->curl);

curl_slist_free_all(j->request_header);

import_compress_free(&j->compress);

if (j->checksum_ctx)

#if PREFER_OPENSSL

EVP_MD_CTX_free(j->checksum_ctx);

gcry_md_close(j->checksum_ctx);

free(j->url);

free(j->etag);

strv_free(j->old_etags);

free(j->payload);

free(j->checksum);

return mfree(j);

}

static void pull_job_finish(PullJob *j, int ret) {

assert(j);

if (IN_SET(j->state, PULL_JOB_DONE, PULL_JOB_FAILED))

return;

if (ret == 0) {

j->state = PULL_JOB_DONE;

j->progress_percent = 100;

log_info("Download of %s complete.", j->url);

} else {

j->state = PULL_JOB_FAILED;

j->error = ret;

}

if (j->on_finished)

j->on_finished(j);

}

static int pull_job_restart(PullJob *j, const char *new_url) {

int r;

assert(j);

assert(new_url);

r = free_and_strdup(&j->url, new_url);

if (r < 0)

return r;

j->state = PULL_JOB_INIT;

j->error = 0;

j->payload = mfree(j->payload);

j->payload_size = 0;

j->written_compressed = 0;

j->written_uncompressed = 0;

j->content_length = UINT64_MAX;

j->etag = mfree(j->etag);

j->etag_exists = false;

j->mtime = 0;

j->checksum = mfree(j->checksum);

curl_glue_remove_and_free(j->glue, j->curl);

j->curl = NULL;

curl_slist_free_all(j->request_header);

j->request_header = NULL;

import_compress_free(&j->compress);

if (j->checksum_ctx) {

#if PREFER_OPENSSL

EVP_MD_CTX_free(j->checksum_ctx);

gcry_md_close(j->checksum_ctx);

j->checksum_ctx = NULL;

}

r = pull_job_begin(j);

if (r < 0)

return r;

return 0;

}

void pull_job_curl_on_finished(CurlGlue *g, CURL *curl, CURLcode result) {

PullJob *j = NULL;

CURLcode code;

long protocol;

int r;

if (curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&j) != CURLE_OK)

return;

if (!j || IN_SET(j->state, PULL_JOB_DONE, PULL_JOB_FAILED))

return;

if (result != CURLE_OK) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Transfer failed: %s", curl_easy_strerror(result));

goto finish;

}

code = curl_easy_getinfo(curl, CURLINFO_PROTOCOL, &protocol);

if (code != CURLE_OK) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve response code: %s", curl_easy_strerror(code));

goto finish;

}

if (IN_SET(protocol, CURLPROTO_HTTP, CURLPROTO_HTTPS)) {

long status;

code = curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &status);

if (code != CURLE_OK) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve response code: %s", curl_easy_strerror(code));

goto finish;

}

if (status == 304) {

log_info("Image already downloaded. Skipping download.");

j->etag_exists = true;

r = 0;

goto finish;

} else if (status >= 300) {

if (status == 404 && j->on_not_found) {

_cleanup_free_ char *new_url = NULL;

/* This resource wasn't found, but the implementor wants to maybe let us know a new URL, query for it. */

r = j->on_not_found(j, &new_url);

if (r < 0)

goto finish;

if (r > 0) { /* A new url to use */

assert(new_url);

r = pull_job_restart(j, new_url);

if (r < 0)

goto finish;

code = curl_easy_getinfo(j->curl, CURLINFO_RESPONSE_CODE, &status);

if (code != CURLE_OK) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve response code: %s", curl_easy_strerror(code));

goto finish;

}

if (status == 0)

return;

}

}

r = log_error_errno(

status == 404 ? SYNTHETIC_ERRNO(ENOMEDIUM) : SYNTHETIC_ERRNO(EIO), /* Make the most common error recognizable */

"HTTP request to %s failed with code %li.", j->url, status);

goto finish;

} else if (status < 200) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "HTTP request to %s finished with unexpected code %li.", j->url, status);

goto finish;

}

}

if (j->state != PULL_JOB_RUNNING) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Premature connection termination.");

goto finish;

}

if (j->content_length != UINT64_MAX &&

j->content_length != j->written_compressed) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Download truncated.");

goto finish;

}

if (j->checksum_ctx) {

unsigned checksum_len;

#if PREFER_OPENSSL

uint8_t k[EVP_MAX_MD_SIZE];

r = EVP_DigestFinal_ex(j->checksum_ctx, k, &checksum_len);

if (r == 0) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to get checksum.");

goto finish;

}

assert(checksum_len <= sizeof k);

const uint8_t *k;

k = gcry_md_read(j->checksum_ctx, GCRY_MD_SHA256);

if (!k) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to get checksum.");

goto finish;

}

checksum_len = gcry_md_get_algo_dlen(GCRY_MD_SHA256);

j->checksum = hexmem(k, checksum_len);

if (!j->checksum) {

r = log_oom();

goto finish;

}

log_debug("SHA256 of %s is %s.", j->url, j->checksum);

}

/* Do a couple of finishing disk operations, but only if we are the sole owner of the file (i.e. no

if (j->disk_fd >= 0) {

if (S_ISREG(j->disk_stat.st_mode)) {

if (j->offset == UINT64_MAX) {

if (j->written_compressed > 0) {

/* Make sure the file size is right, in case the file was sparse and we just seeked

if (ftruncate(j->disk_fd, j->written_uncompressed) < 0) {

r = log_error_errno(errno, "Failed to truncate file: %m");

goto finish;

}

}

if (j->etag)

(void) fsetxattr(j->disk_fd, "user.source_etag", j->etag, strlen(j->etag), 0);

if (j->url)

(void) fsetxattr(j->disk_fd, "user.source_url", j->url, strlen(j->url), 0);

if (j->mtime != 0) {

struct timespec ut;

timespec_store(&ut, j->mtime);

if (futimens(j->disk_fd, (struct timespec[]) { ut, ut }) < 0)

log_debug_errno(errno, "Failed to adjust atime/mtime of created image, ignoring: %m");

r = fd_setcrtime(j->disk_fd, j->mtime);

if (r < 0)

log_debug_errno(r, "Failed to adjust crtime of created image, ignoring: %m");

}

}

if (j->sync) {

r = fsync_full(j->disk_fd);

if (r < 0) {

log_error_errno(r, "Failed to synchronize file to disk: %m");

goto finish;

}

}

} else if (S_ISBLK(j->disk_stat.st_mode) && j->sync) {

if (fsync(j->disk_fd) < 0) {

r = log_error_errno(errno, "Failed to synchronize block device: %m");

goto finish;

}

}

}

log_info("Acquired %s.", FORMAT_BYTES(j->written_uncompressed));

r = 0;

finish:

pull_job_finish(j, r);

}

static int pull_job_write_uncompressed(const void *p, size_t sz, void *userdata) {

PullJob *j = userdata;

bool too_much = false;

int r;

assert(j);

assert(p);

assert(sz > 0);

if (j->written_uncompressed > UINT64_MAX - sz)

return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "File too large, overflow");

if (j->written_uncompressed >= j->uncompressed_max) {

too_much = true;

goto finish;

}

if (j->written_uncompressed + sz > j->uncompressed_max) {

too_much = true;

sz = j->uncompressed_max - j->written_uncompressed; /* since we have the data in memory

}

if (j->disk_fd >= 0) {

if (S_ISREG(j->disk_stat.st_mode) && j->offset == UINT64_MAX) {

ssize_t n;

n = sparse_write(j->disk_fd, p, sz, 64);

if (n < 0)

return log_error_errno((int) n, "Failed to write file: %m");

if ((size_t) n < sz)

return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short write");

} else {

r = loop_write(j->disk_fd, p, sz, false);

if (r < 0)

return log_error_errno(r, "Failed to write file: %m");

}

}

if (j->disk_fd < 0 || j->force_memory) {

if (!GREEDY_REALLOC(j->payload, j->payload_size + sz))

return log_oom();

memcpy(j->payload + j->payload_size, p, sz);

j->payload_size += sz;

}

j->written_uncompressed += sz;

finish:

if (too_much)

return log_error_errno(SYNTHETIC_ERRNO(EFBIG), "File overly large, refusing.");

return 0;

}

static int pull_job_write_compressed(PullJob *j, void *p, size_t sz) {

int r;

assert(j);

assert(p);

if (sz <= 0)

return 0;

if (j->written_compressed + sz < j->written_compressed)

return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "File too large, overflow");

if (j->written_compressed + sz > j->compressed_max)

return log_error_errno(SYNTHETIC_ERRNO(EFBIG), "File overly large, refusing.");

if (j->content_length != UINT64_MAX &&

j->written_compressed + sz > j->content_length)

return log_error_errno(SYNTHETIC_ERRNO(EFBIG),

"Content length incorrect.");

if (j->checksum_ctx) {

#if PREFER_OPENSSL

r = EVP_DigestUpdate(j->checksum_ctx, p, sz);

if (r == 0)

return log_error_errno(SYNTHETIC_ERRNO(EIO),

"Could not hash chunk.");

gcry_md_write(j->checksum_ctx, p, sz);

}

r = import_uncompress(&j->compress, p, sz, pull_job_write_uncompressed, j);

if (r < 0)

return r;

j->written_compressed += sz;

return 0;

}

static int pull_job_open_disk(PullJob *j) {

int r;

assert(j);

if (j->on_open_disk) {

r = j->on_open_disk(j);

if (r < 0)

return r;

}

if (j->disk_fd >= 0) {

if (fstat(j->disk_fd, &j->disk_stat) < 0)

return log_error_errno(errno, "Failed to stat disk file: %m");

if (j->offset != UINT64_MAX) {

if (lseek(j->disk_fd, j->offset, SEEK_SET) == (off_t) -1)

return log_error_errno(errno, "Failed to seek on file descriptor: %m");

}

}

if (j->calc_checksum) {

#if PREFER_OPENSSL

j->checksum_ctx = EVP_MD_CTX_new();

if (!j->checksum_ctx)

return log_oom();

r = EVP_DigestInit_ex(j->checksum_ctx, EVP_sha256(), NULL);

if (r == 0)

return log_error_errno(SYNTHETIC_ERRNO(EIO),

"Failed to initialize hash context.");

initialize_libgcrypt(false);

if (gcry_md_open(&j->checksum_ctx, GCRY_MD_SHA256, 0) != 0)

return log_error_errno(SYNTHETIC_ERRNO(EIO),

"Failed to initialize hash context.");

}

return 0;

}

static int pull_job_detect_compression(PullJob *j) {

_cleanup_free_ uint8_t *stub = NULL;

size_t stub_size;

int r;

assert(j);

r = import_uncompress_detect(&j->compress, j->payload, j->payload_size);

if (r < 0)

return log_error_errno(r, "Failed to initialize compressor: %m");

if (r == 0)

return 0;

log_debug("Stream is compressed: %s", import_compress_type_to_string(j->compress.type));

r = pull_job_open_disk(j);

if (r < 0)

return r;

/* Now, take the payload we read so far, and decompress it */

stub = j->payload;

stub_size = j->payload_size;

j->payload = NULL;

j->payload_size = 0;

j->state = PULL_JOB_RUNNING;

r = pull_job_write_compressed(j, stub, stub_size);

if (r < 0)

return r;

return 0;

}

static size_t pull_job_write_callback(void *contents, size_t size, size_t nmemb, void *userdata) {

PullJob *j = userdata;

size_t sz = size * nmemb;

int r;

assert(contents);

assert(j);

switch (j->state) {

case PULL_JOB_ANALYZING:

/* Let's first check what it actually is */

if (!GREEDY_REALLOC(j->payload, j->payload_size + sz)) {

r = log_oom();

goto fail;

}

memcpy(j->payload + j->payload_size, contents, sz);

j->payload_size += sz;

r = pull_job_detect_compression(j);

if (r < 0)

goto fail;

break;

case PULL_JOB_RUNNING:

r = pull_job_write_compressed(j, contents, sz);

if (r < 0)

goto fail;

break;

case PULL_JOB_DONE:

case PULL_JOB_FAILED:

r = -ESTALE;

goto fail;

default:

assert_not_reached();

}

return sz;

fail:

pull_job_finish(j, r);

return 0;

}

static int http_status_ok(CURLcode status) {

/* Consider all HTTP status code in the 2xx range as OK */

return status >= 200 && status <= 299;

}

static int http_status_etag_exists(CURLcode status) {

/* This one is special, it's triggered by our etag mgmt logic */

return status == 304;

}

static size_t pull_job_header_callback(void *contents, size_t size, size_t nmemb, void *userdata) {

_cleanup_free_ char *length = NULL, *last_modified = NULL, *etag = NULL;

size_t sz = size * nmemb;

PullJob *j = userdata;

CURLcode code;

long status;

int r;

assert(contents);

assert(j);

if (IN_SET(j->state, PULL_JOB_DONE, PULL_JOB_FAILED)) {

r = -ESTALE;

goto fail;

}

assert(j->state == PULL_JOB_ANALYZING);

code = curl_easy_getinfo(j->curl, CURLINFO_RESPONSE_CODE, &status);

if (code != CURLE_OK) {

r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve response code: %s", curl_easy_strerror(code));

goto fail;

}

if (http_status_ok(status) || http_status_etag_exists(status)) {

/* Check Etag on OK and etag exists responses. */

r = curl_header_strdup(contents, sz, "ETag:", &etag);

if (r < 0) {

log_oom();

goto fail;

}

if (r > 0) {

free_and_replace(j->etag, etag);

if (strv_contains(j->old_etags, j->etag)) {

log_info("Image already downloaded. Skipping download. (%s)", j->etag);

j->etag_exists = true;

pull_job_finish(j, 0);

return sz;

}

return sz;

}

}

if (!http_status_ok(status)) /* Let's ignore the rest here, these requests are probably redirects and

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, &j->content_length);

if (j->content_length != UINT64_MAX) {

if (j->content_length > j->compressed_max) {

r = log_error_errno(SYNTHETIC_ERRNO(EFBIG), "Content too large.");

goto fail;

}

log_info("Downloading %s for %s.", FORMAT_BYTES(j->content_length), j->url);

}

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, &j->mtime);

return sz;

}

if (j->on_header) {

r = j->on_header(j, contents, sz);

if (r < 0)

goto fail;

}

return sz;

fail:

pull_job_finish(j, r);

return 0;

}

static int pull_job_progress_callback(void *userdata, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow) {

PullJob *j = userdata;

unsigned percent;

usec_t n;

assert(j);

if (dltotal <= 0)

return 0;

percent = ((100 * dlnow) / dltotal);

n = now(CLOCK_MONOTONIC);

if (n > j->last_status_usec + USEC_PER_SEC &&

percent != j->progress_percent &&

dlnow < dltotal) {

if (n - j->start_usec > USEC_PER_SEC && dlnow > 0) {

usec_t left, done;

done = n - j->start_usec;

left = (usec_t) (((double) done * (double) dltotal) / dlnow) - done;

log_info("Got %u%% of %s. %s left at %s/s.",

percent,

j->url,

FORMAT_TIMESPAN(left, USEC_PER_SEC),

FORMAT_BYTES((uint64_t) ((double) dlnow / ((double) done / (double) USEC_PER_SEC))));

} else

log_info("Got %u%% of %s.", percent, j->url);

j->progress_percent = percent;

j->last_status_usec = n;

if (j->on_progress)

j->on_progress(j);

}

return 0;

}

int pull_job_new(

void *userdata) {

_cleanup_(pull_job_unrefp) PullJob *j = NULL;

_cleanup_free_ char *u = NULL;

assert(url);

assert(glue);

assert(ret);

u = strdup(url);

if (!u)

return -ENOMEM;

j = new(PullJob, 1);

if (!j)

return -ENOMEM;

*j = (PullJob) {

.state = PULL_JOB_INIT,

.disk_fd = -1,

.close_disk_fd = true,

.userdata = userdata,

.glue = glue,

.content_length = UINT64_MAX,

.start_usec = now(CLOCK_MONOTONIC),

.compressed_max = 64LLU * 1024LLU * 1024LLU * 1024LLU, /* 64GB safety limit */

.uncompressed_max = 64LLU * 1024LLU * 1024LLU * 1024LLU, /* 64GB safety limit */

.url = TAKE_PTR(u),

.offset = UINT64_MAX,

.sync = true,

};

*ret = TAKE_PTR(j);

return 0;

}

int pull_job_begin(PullJob *j) {

int r;

assert(j);

if (j->state != PULL_JOB_INIT)

return -EBUSY;

r = curl_glue_make(&j->curl, j->url, j);

if (r < 0)

return r;

if (!strv_isempty(j->old_etags)) {

_cleanup_free_ char *cc = NULL, *hdr = NULL;

cc = strv_join(j->old_etags, ", ");

if (!cc)

return -ENOMEM;

hdr = strjoin("If-None-Match: ", cc);

if (!hdr)

return -ENOMEM;

if (!j->request_header) {

j->request_header = curl_slist_new(hdr, NULL);

if (!j->request_header)

return -ENOMEM;

} else {

struct curl_slist *l;

l = curl_slist_append(j->request_header, hdr);

if (!l)

return -ENOMEM;

j->request_header = l;

}

}

if (j->request_header) {

if (curl_easy_setopt(j->curl, CURLOPT_HTTPHEADER, j->request_header) != CURLE_OK)

return -EIO;

}

if (curl_easy_setopt(j->curl, CURLOPT_WRITEFUNCTION, pull_job_write_callback) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_WRITEDATA, j) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_HEADERFUNCTION, pull_job_header_callback) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_HEADERDATA, j) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_XFERINFOFUNCTION, pull_job_progress_callback) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_XFERINFODATA, j) != CURLE_OK)

return -EIO;

if (curl_easy_setopt(j->curl, CURLOPT_NOPROGRESS, 0) != CURLE_OK)

return -EIO;

r = curl_glue_add(j->glue, j->curl);

if (r < 0)

return r;

j->state = PULL_JOB_ANALYZING;

return 0;

}