/*-

* Copyright (c) 2009-2013 Juan Romero Pardines

* Copyright (c) 2000-2004 Dag-Erling Coïdan Smørgrav

* All rights reserved.

*

* Redistribution and use in source and binary forms, with or without

* modification, are permitted provided that the following conditions

* are met:

* 1. Redistributions of source code must retain the above copyright

* notice, this list of conditions and the following disclaimer

* in this position and unchanged.

* 2. Redistributions in binary form must reproduce the above copyright

* notice, this list of conditions and the following disclaimer in the

* documentation and/or other materials provided with the distribution.

* 3. The name of the author may not be used to endorse or promote products

* derived from this software without specific prior written permission

*

* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*

* From FreeBSD fetch(8):

* $FreeBSD: src/usr.bin/fetch/fetch.c,v 1.84.2.1 2009/08/03 08:13:06 kensmith Exp $

*/

#include <sys/param.h>

#include <sys/stat.h>

#include <sys/time.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <errno.h>

#include <fcntl.h>

#include <libgen.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>

#include <unistd.h>

#include <openssl/sha.h>

#include "xbps_api_impl.h"

#include "fetch.h"

#include "compat.h"

/**

* @file lib/download.c

* @brief Download routines

* @defgroup download Download functions

*

* XBPS download related functions, frontend for NetBSD's libfetch.

*/

static const char *

print_time(time_t *t)

{

struct tm tm;

static char buf[255];

gmtime_r(t, &tm);

strftime(buf, sizeof(buf), "%d %b %Y %H:%M", &tm);

return buf;

}

void HIDDEN

xbps_fetch_set_cache_connection(int global, int per_host)

{

if (global == 0)

global = XBPS_FETCH_CACHECONN;

if (per_host == 0)

per_host = XBPS_FETCH_CACHECONN_HOST;

fetchConnectionCacheInit(global, per_host);

}

void HIDDEN

xbps_fetch_unset_cache_connection(void)

{

fetchConnectionCacheClose();

}

const char *

xbps_fetch_error_string(void)

{

if (fetchLastErrCode == 0 || fetchLastErrCode == FETCH_OK)

return NULL;

return fetchLastErrString;

}

int

xbps_fetch_file_dest_sha256(struct xbps_handle *xhp, const char *uri, const char *filename, const char *flags, unsigned char *digest, size_t digestlen)

{

struct stat st, st_tmpfile, *stp;

struct url *url = NULL;

struct url_stat url_st;

struct fetchIO *fio = NULL;

struct timespec ts[2];

off_t bytes_dload = 0;

ssize_t bytes_read = 0, bytes_written = 0;

char buf[4096], *tempfile = NULL;

char fetch_flags[8];

int fd = -1, rv = 0;

bool refetch = false, restart = false;

SHA256_CTX sha256;

assert(xhp);

assert(uri);

if (digest != NULL) {

assert(digestlen >= XBPS_SHA256_DIGEST_SIZE);

if (digestlen < XBPS_SHA256_DIGEST_SIZE) {

errno = ENOBUFS;

return -1;

}

SHA256_Init(&sha256);

}

/* Extern vars declared in libfetch */

fetchLastErrCode = 0;

if (!filename || (url = fetchParseURL(uri)) == NULL)

return -1;

memset(&fetch_flags, 0, sizeof(fetch_flags));

if (flags != NULL)

xbps_strlcpy(fetch_flags, flags, 7);

tempfile = xbps_xasprintf("%s.part", filename);

/*

* Check if we have to resume a transfer.

*/

memset(&st_tmpfile, 0, sizeof(st_tmpfile));

if (stat(tempfile, &st_tmpfile) == 0) {

if (st_tmpfile.st_size > 0)

restart = true;

} else {

if (errno != ENOENT) {

rv = -1;

goto fetch_file_out;

}

}

/*

* Check if we have to refetch a transfer.

*/

memset(&st, 0, sizeof(st));

if (stat(filename, &st) == 0) {

refetch = true;

url->last_modified = st.st_mtime;

xbps_strlcat(fetch_flags, "i", sizeof(fetch_flags));

} else {

if (errno != ENOENT) {

rv = -1;

goto fetch_file_out;

}

}

if (refetch && !restart) {

/* fetch the whole file, filename available */

stp = &st;

} else {

/* resume transfer, partial file found */

stp = &st_tmpfile;

url->offset = stp->st_size;

}

/*

* Issue a GET request.

*/

fio = fetchXGet(url, &url_st, fetch_flags);

/* debug stuff */

xbps_dbg_printf("st.st_size: %zd\n", (ssize_t)stp->st_size);

xbps_dbg_printf("st.st_atime: %s\n", print_time(&stp->st_atime));

xbps_dbg_printf("st.st_mtime: %s\n", print_time(&stp->st_mtime));

xbps_dbg_printf("url_stat.size: %zd\n", (ssize_t)url_st.size);

xbps_dbg_printf("url_stat.atime: %s\n", print_time(&url_st.atime));

xbps_dbg_printf("url_stat.mtime: %s\n", print_time(&url_st.mtime));

if (fio == NULL) {

if (fetchLastErrCode == FETCH_UNCHANGED) {

/* Last-Modified matched */

goto fetch_file_out;

} else if (fetchLastErrCode == FETCH_PROTO && url_st.size == stp->st_size) {

/* 413, requested offset == length */

goto rename_file;

}

rv = -1;

goto fetch_file_out;

}

if (url_st.size == -1) {

xbps_dbg_printf("Remote file size is unknown, resume "

"not possible...\n");

restart = false;

} else if (stp->st_size > url_st.size) {

/*

* Remove local file if bigger than remote, and refetch the

* whole shit again.

*/

xbps_dbg_printf("Local file %s is greater than remote, "

"removing local file and refetching...\n", filename);

(void)remove(tempfile);

restart = false;

}

xbps_dbg_printf("url->scheme: %s\n", url->scheme);

xbps_dbg_printf("url->host: %s\n", url->host);

xbps_dbg_printf("url->port: %d\n", url->port);

xbps_dbg_printf("url->doc: %s\n", url->doc);

xbps_dbg_printf("url->offset: %zd\n", (ssize_t)url->offset);

xbps_dbg_printf("url->length: %zu\n", url->length);

xbps_dbg_printf("url->last_modified: %s\n",

print_time(&url->last_modified));

/*

* If restarting, open the file for appending otherwise create it.

*/

if (restart)

fd = open(tempfile, O_RDWR|O_CLOEXEC);

else

fd = open(tempfile, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC, 0644);

if (fd == -1) {

rv = -1;

goto fetch_file_out;

}

/*

* If restarting and digest was requested, read the current data

* and feed into sha256 hash.

*/

if (restart) {

if (digest) {

while ((bytes_read = read(fd, buf, sizeof(buf))) > 0) {

SHA256_Update(&sha256, buf, bytes_read);

}

if (bytes_read == -1) {

xbps_dbg_printf("IO error while reading %s: %s\n",

tempfile, strerror(errno));

errno = EIO;

rv = -1;

goto fetch_file_out;

}

}

lseek(fd, 0, SEEK_END);

}

/*

* Initialize data for the fetch progress function callback

* and let the user know that the transfer is going to start

* immediately.

*/

xbps_set_cb_fetch(xhp, url_st.size, url->offset, url->offset,

filename, true, false, false);

/*

* Start fetching requested file.

*/

while ((bytes_read = fetchIO_read(fio, buf, sizeof(buf))) > 0) {

if (digest)

SHA256_Update(&sha256, buf, bytes_read);

bytes_written = write(fd, buf, (size_t)bytes_read);

if (bytes_written != bytes_read) {

xbps_dbg_printf("Couldn't write to %s!\n", tempfile);

rv = -1;

goto fetch_file_out;

}

bytes_dload += bytes_read;

/*

* Let the fetch progress callback know that

* we are sucking more bytes from it.

*/

xbps_set_cb_fetch(xhp, url_st.size, url->offset,

url->offset + bytes_dload,

filename, false, true, false);

}

if (bytes_read == -1) {

xbps_dbg_printf("IO error while fetching %s: %s\n",

filename, fetchLastErrString);

errno = EIO;

rv = -1;

goto fetch_file_out;

} else if (url_st.size > 0 && ((bytes_dload + url->offset) != url_st.size)) {

xbps_dbg_printf("file %s is truncated\n", filename);

errno = EIO;

rv = -1;

goto fetch_file_out;

}

/*

* Let the fetch progress callback know that the file

* has been fetched.

*/

xbps_set_cb_fetch(xhp, url_st.size, url->offset, bytes_dload,

filename, false, false, true);

/*

* Update mtime in local file to match remote file if transfer

* was successful.

*/

ts[0].tv_sec = url_st.atime ? url_st.atime : url_st.mtime;

ts[1].tv_sec = url_st.mtime;

ts[0].tv_nsec = ts[1].tv_nsec = 0;

if (futimens(fd, ts) == -1) {

rv = -1;

goto fetch_file_out;

}

(void)close(fd);

fd = -1;

rename_file:

/* File downloaded successfully, rename to destfile */

if (rename(tempfile, filename) == -1) {

xbps_dbg_printf("failed to rename %s to %s: %s",

tempfile, filename, strerror(errno));

rv = -1;

goto fetch_file_out;

}

rv = 1;

if (digest)

SHA256_Final(digest, &sha256);

fetch_file_out:

if (fio != NULL)

fetchIO_close(fio);

if (fd != -1)

(void)close(fd);

if (url != NULL)

fetchFreeURL(url);

free(tempfile);

return rv;

}

int

xbps_fetch_file_dest(struct xbps_handle *xhp, const char *uri,

const char *filename, const char *flags)

{

return xbps_fetch_file_dest_sha256(xhp, uri, filename, flags, NULL, 0);

}

int

xbps_fetch_file_sha256(struct xbps_handle *xhp, const char *uri,

const char *flags, unsigned char *digest, size_t digestlen)

{

const char *filename;

/*

* Get the filename specified in URI argument.

*/

if ((filename = strrchr(uri, '/')) == NULL)

return -1;

filename++;

return xbps_fetch_file_dest_sha256(xhp, uri, filename, flags,

digest, digestlen);

}

int

xbps_fetch_file(struct xbps_handle *xhp, const char *uri, const char *flags)

{

return xbps_fetch_file_sha256(xhp, uri, flags, NULL, 0);

}