qemu-e2k/block/curl.c
Max Reitz 4e504535c1 block/curl: Do not wait for data beyond EOF
libcurl will only give us as much data as there is, not more. The block
layer will deny requests beyond the end of file for us; but since this
block driver is still using a sector-based interface, we can still get
in trouble if the file size is not a multiple of 512.

While we have already made sure not to attempt transfers beyond the end
of the file, we are currently still trying to receive data from there if
the original request exceeds the file size. This patch fixes this issue
and invokes qemu_iovec_memset() on the iovec's tail.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20161025025431.24714-5-mreitz@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00

948 lines
27 KiB
C

/*
* QEMU Block driver for CURL images
*
* Copyright (c) 2009 Alexander Graf <agraf@suse.de>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
#include "block/block_int.h"
#include "qapi/qmp/qbool.h"
#include "qapi/qmp/qstring.h"
#include "crypto/secret.h"
#include <curl/curl.h>
#include "qemu/cutils.h"
// #define DEBUG_CURL
// #define DEBUG_VERBOSE
#ifdef DEBUG_CURL
#define DEBUG_CURL_PRINT 1
#else
#define DEBUG_CURL_PRINT 0
#endif
#define DPRINTF(fmt, ...) \
do { \
if (DEBUG_CURL_PRINT) { \
fprintf(stderr, fmt, ## __VA_ARGS__); \
} \
} while (0)
#if LIBCURL_VERSION_NUM >= 0x071000
/* The multi interface timer callback was introduced in 7.16.0 */
#define NEED_CURL_TIMER_CALLBACK
#define HAVE_SOCKET_ACTION
#endif
#ifndef HAVE_SOCKET_ACTION
/* If curl_multi_socket_action isn't available, define it statically here in
* terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
* less efficient but still safe. */
static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
curl_socket_t sockfd,
int ev_bitmask,
int *running_handles)
{
return curl_multi_socket(multi_handle, sockfd, running_handles);
}
#define curl_multi_socket_action __curl_multi_socket_action
#endif
#define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
CURLPROTO_FTP | CURLPROTO_FTPS)
#define CURL_NUM_STATES 8
#define CURL_NUM_ACB 8
#define READ_AHEAD_DEFAULT (256 * 1024)
#define CURL_TIMEOUT_DEFAULT 5
#define CURL_TIMEOUT_MAX 10000
#define FIND_RET_NONE 0
#define FIND_RET_OK 1
#define FIND_RET_WAIT 2
#define CURL_BLOCK_OPT_URL "url"
#define CURL_BLOCK_OPT_READAHEAD "readahead"
#define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
#define CURL_BLOCK_OPT_TIMEOUT "timeout"
#define CURL_BLOCK_OPT_COOKIE "cookie"
#define CURL_BLOCK_OPT_USERNAME "username"
#define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
#define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
#define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
struct BDRVCURLState;
typedef struct CURLAIOCB {
BlockAIOCB common;
QEMUIOVector *qiov;
int64_t sector_num;
int nb_sectors;
size_t start;
size_t end;
} CURLAIOCB;
typedef struct CURLSocket {
int fd;
QLIST_ENTRY(CURLSocket) next;
} CURLSocket;
typedef struct CURLState
{
struct BDRVCURLState *s;
CURLAIOCB *acb[CURL_NUM_ACB];
CURL *curl;
QLIST_HEAD(, CURLSocket) sockets;
char *orig_buf;
size_t buf_start;
size_t buf_off;
size_t buf_len;
char range[128];
char errmsg[CURL_ERROR_SIZE];
char in_use;
} CURLState;
typedef struct BDRVCURLState {
CURLM *multi;
QEMUTimer timer;
size_t len;
CURLState states[CURL_NUM_STATES];
char *url;
size_t readahead_size;
bool sslverify;
uint64_t timeout;
char *cookie;
bool accept_range;
AioContext *aio_context;
char *username;
char *password;
char *proxyusername;
char *proxypassword;
} BDRVCURLState;
static void curl_clean_state(CURLState *s);
static void curl_multi_do(void *arg);
static void curl_multi_read(void *arg);
#ifdef NEED_CURL_TIMER_CALLBACK
static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
{
BDRVCURLState *s = opaque;
DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
if (timeout_ms == -1) {
timer_del(&s->timer);
} else {
int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
timer_mod(&s->timer,
qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
}
return 0;
}
#endif
static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
void *userp, void *sp)
{
BDRVCURLState *s;
CURLState *state = NULL;
CURLSocket *socket;
curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
s = state->s;
QLIST_FOREACH(socket, &state->sockets, next) {
if (socket->fd == fd) {
if (action == CURL_POLL_REMOVE) {
QLIST_REMOVE(socket, next);
g_free(socket);
}
break;
}
}
if (!socket) {
socket = g_new0(CURLSocket, 1);
socket->fd = fd;
QLIST_INSERT_HEAD(&state->sockets, socket, next);
}
socket = NULL;
DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, (int)fd);
switch (action) {
case CURL_POLL_IN:
aio_set_fd_handler(s->aio_context, fd, false,
curl_multi_read, NULL, state);
break;
case CURL_POLL_OUT:
aio_set_fd_handler(s->aio_context, fd, false,
NULL, curl_multi_do, state);
break;
case CURL_POLL_INOUT:
aio_set_fd_handler(s->aio_context, fd, false,
curl_multi_read, curl_multi_do, state);
break;
case CURL_POLL_REMOVE:
aio_set_fd_handler(s->aio_context, fd, false,
NULL, NULL, NULL);
break;
}
return 0;
}
static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
{
BDRVCURLState *s = opaque;
size_t realsize = size * nmemb;
const char *accept_line = "Accept-Ranges: bytes";
if (realsize >= strlen(accept_line)
&& strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
s->accept_range = true;
}
return realsize;
}
static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
{
CURLState *s = ((CURLState*)opaque);
size_t realsize = size * nmemb;
int i;
DPRINTF("CURL: Just reading %zd bytes\n", realsize);
if (!s || !s->orig_buf) {
goto read_end;
}
if (s->buf_off >= s->buf_len) {
/* buffer full, read nothing */
goto read_end;
}
realsize = MIN(realsize, s->buf_len - s->buf_off);
memcpy(s->orig_buf + s->buf_off, ptr, realsize);
s->buf_off += realsize;
for(i=0; i<CURL_NUM_ACB; i++) {
CURLAIOCB *acb = s->acb[i];
if (!acb)
continue;
if ((s->buf_off >= acb->end)) {
size_t request_length = acb->nb_sectors * BDRV_SECTOR_SIZE;
qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
acb->end - acb->start);
if (acb->end - acb->start < request_length) {
size_t offset = acb->end - acb->start;
qemu_iovec_memset(acb->qiov, offset, 0,
request_length - offset);
}
acb->common.cb(acb->common.opaque, 0);
qemu_aio_unref(acb);
s->acb[i] = NULL;
}
}
read_end:
/* curl will error out if we do not return this value */
return size * nmemb;
}
static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
CURLAIOCB *acb)
{
int i;
size_t end = start + len;
size_t clamped_end = MIN(end, s->len);
size_t clamped_len = clamped_end - start;
for (i=0; i<CURL_NUM_STATES; i++) {
CURLState *state = &s->states[i];
size_t buf_end = (state->buf_start + state->buf_off);
size_t buf_fend = (state->buf_start + state->buf_len);
if (!state->orig_buf)
continue;
if (!state->buf_off)
continue;
// Does the existing buffer cover our section?
if ((start >= state->buf_start) &&
(start <= buf_end) &&
(clamped_end >= state->buf_start) &&
(clamped_end <= buf_end))
{
char *buf = state->orig_buf + (start - state->buf_start);
qemu_iovec_from_buf(acb->qiov, 0, buf, clamped_len);
if (clamped_len < len) {
qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len);
}
acb->common.cb(acb->common.opaque, 0);
return FIND_RET_OK;
}
// Wait for unfinished chunks
if (state->in_use &&
(start >= state->buf_start) &&
(start <= buf_fend) &&
(clamped_end >= state->buf_start) &&
(clamped_end <= buf_fend))
{
int j;
acb->start = start - state->buf_start;
acb->end = acb->start + clamped_len;
for (j=0; j<CURL_NUM_ACB; j++) {
if (!state->acb[j]) {
state->acb[j] = acb;
return FIND_RET_WAIT;
}
}
}
}
return FIND_RET_NONE;
}
static void curl_multi_check_completion(BDRVCURLState *s)
{
int msgs_in_queue;
/* Try to find done transfers, so we can free the easy
* handle again. */
for (;;) {
CURLMsg *msg;
msg = curl_multi_info_read(s->multi, &msgs_in_queue);
/* Quit when there are no more completions */
if (!msg)
break;
if (msg->msg == CURLMSG_DONE) {
CURLState *state = NULL;
curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
(char **)&state);
/* ACBs for successful messages get completed in curl_read_cb */
if (msg->data.result != CURLE_OK) {
int i;
static int errcount = 100;
/* Don't lose the original error message from curl, since
* it contains extra data.
*/
if (errcount > 0) {
error_report("curl: %s", state->errmsg);
if (--errcount == 0) {
error_report("curl: further errors suppressed");
}
}
for (i = 0; i < CURL_NUM_ACB; i++) {
CURLAIOCB *acb = state->acb[i];
if (acb == NULL) {
continue;
}
acb->common.cb(acb->common.opaque, -EPROTO);
qemu_aio_unref(acb);
state->acb[i] = NULL;
}
}
curl_clean_state(state);
break;
}
}
}
static void curl_multi_do(void *arg)
{
CURLState *s = (CURLState *)arg;
CURLSocket *socket, *next_socket;
int running;
int r;
if (!s->s->multi) {
return;
}
/* Need to use _SAFE because curl_multi_socket_action() may trigger
* curl_sock_cb() which might modify this list */
QLIST_FOREACH_SAFE(socket, &s->sockets, next, next_socket) {
do {
r = curl_multi_socket_action(s->s->multi, socket->fd, 0, &running);
} while (r == CURLM_CALL_MULTI_PERFORM);
}
}
static void curl_multi_read(void *arg)
{
CURLState *s = (CURLState *)arg;
curl_multi_do(arg);
curl_multi_check_completion(s->s);
}
static void curl_multi_timeout_do(void *arg)
{
#ifdef NEED_CURL_TIMER_CALLBACK
BDRVCURLState *s = (BDRVCURLState *)arg;
int running;
if (!s->multi) {
return;
}
curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
curl_multi_check_completion(s);
#else
abort();
#endif
}
static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
{
CURLState *state = NULL;
int i, j;
do {
for (i=0; i<CURL_NUM_STATES; i++) {
for (j=0; j<CURL_NUM_ACB; j++)
if (s->states[i].acb[j])
continue;
if (s->states[i].in_use)
continue;
state = &s->states[i];
state->in_use = 1;
break;
}
if (!state) {
aio_poll(bdrv_get_aio_context(bs), true);
}
} while(!state);
if (!state->curl) {
state->curl = curl_easy_init();
if (!state->curl) {
return NULL;
}
curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
(long) s->sslverify);
if (s->cookie) {
curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
}
curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
(void *)curl_read_cb);
curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
if (s->username) {
curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
}
if (s->password) {
curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
}
if (s->proxyusername) {
curl_easy_setopt(state->curl,
CURLOPT_PROXYUSERNAME, s->proxyusername);
}
if (s->proxypassword) {
curl_easy_setopt(state->curl,
CURLOPT_PROXYPASSWORD, s->proxypassword);
}
/* Restrict supported protocols to avoid security issues in the more
* obscure protocols. For example, do not allow POP3/SMTP/IMAP see
* CVE-2013-0249.
*
* Restricting protocols is only supported from 7.19.4 upwards.
*/
#if LIBCURL_VERSION_NUM >= 0x071304
curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
#endif
#ifdef DEBUG_VERBOSE
curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
#endif
}
QLIST_INIT(&state->sockets);
state->s = s;
return state;
}
static void curl_clean_state(CURLState *s)
{
if (s->s->multi)
curl_multi_remove_handle(s->s->multi, s->curl);
while (!QLIST_EMPTY(&s->sockets)) {
CURLSocket *socket = QLIST_FIRST(&s->sockets);
QLIST_REMOVE(socket, next);
g_free(socket);
}
s->in_use = 0;
}
static void curl_parse_filename(const char *filename, QDict *options,
Error **errp)
{
qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
}
static void curl_detach_aio_context(BlockDriverState *bs)
{
BDRVCURLState *s = bs->opaque;
int i;
for (i = 0; i < CURL_NUM_STATES; i++) {
if (s->states[i].in_use) {
curl_clean_state(&s->states[i]);
}
if (s->states[i].curl) {
curl_easy_cleanup(s->states[i].curl);
s->states[i].curl = NULL;
}
g_free(s->states[i].orig_buf);
s->states[i].orig_buf = NULL;
}
if (s->multi) {
curl_multi_cleanup(s->multi);
s->multi = NULL;
}
timer_del(&s->timer);
}
static void curl_attach_aio_context(BlockDriverState *bs,
AioContext *new_context)
{
BDRVCURLState *s = bs->opaque;
aio_timer_init(new_context, &s->timer,
QEMU_CLOCK_REALTIME, SCALE_NS,
curl_multi_timeout_do, s);
assert(!s->multi);
s->multi = curl_multi_init();
s->aio_context = new_context;
curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
#ifdef NEED_CURL_TIMER_CALLBACK
curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
#endif
}
static QemuOptsList runtime_opts = {
.name = "curl",
.head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
.desc = {
{
.name = CURL_BLOCK_OPT_URL,
.type = QEMU_OPT_STRING,
.help = "URL to open",
},
{
.name = CURL_BLOCK_OPT_READAHEAD,
.type = QEMU_OPT_SIZE,
.help = "Readahead size",
},
{
.name = CURL_BLOCK_OPT_SSLVERIFY,
.type = QEMU_OPT_BOOL,
.help = "Verify SSL certificate"
},
{
.name = CURL_BLOCK_OPT_TIMEOUT,
.type = QEMU_OPT_NUMBER,
.help = "Curl timeout"
},
{
.name = CURL_BLOCK_OPT_COOKIE,
.type = QEMU_OPT_STRING,
.help = "Pass the cookie or list of cookies with each request"
},
{
.name = CURL_BLOCK_OPT_USERNAME,
.type = QEMU_OPT_STRING,
.help = "Username for HTTP auth"
},
{
.name = CURL_BLOCK_OPT_PASSWORD_SECRET,
.type = QEMU_OPT_STRING,
.help = "ID of secret used as password for HTTP auth",
},
{
.name = CURL_BLOCK_OPT_PROXY_USERNAME,
.type = QEMU_OPT_STRING,
.help = "Username for HTTP proxy auth"
},
{
.name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
.type = QEMU_OPT_STRING,
.help = "ID of secret used as password for HTTP proxy auth",
},
{ /* end of list */ }
},
};
static int curl_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
BDRVCURLState *s = bs->opaque;
CURLState *state = NULL;
QemuOpts *opts;
Error *local_err = NULL;
const char *file;
const char *cookie;
double d;
const char *secretid;
static int inited = 0;
if (flags & BDRV_O_RDWR) {
error_setg(errp, "curl block device does not support writes");
return -EROFS;
}
opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_noclean;
}
s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
READ_AHEAD_DEFAULT);
if ((s->readahead_size & 0x1ff) != 0) {
error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
s->readahead_size);
goto out_noclean;
}
s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
CURL_TIMEOUT_DEFAULT);
if (s->timeout > CURL_TIMEOUT_MAX) {
error_setg(errp, "timeout parameter is too large or negative");
goto out_noclean;
}
s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
s->cookie = g_strdup(cookie);
file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
if (file == NULL) {
error_setg(errp, "curl block driver requires an 'url' option");
goto out_noclean;
}
s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
if (secretid) {
s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
if (!s->password) {
goto out_noclean;
}
}
s->proxyusername = g_strdup(
qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
if (secretid) {
s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
if (!s->proxypassword) {
goto out_noclean;
}
}
if (!inited) {
curl_global_init(CURL_GLOBAL_ALL);
inited = 1;
}
DPRINTF("CURL: Opening %s\n", file);
s->aio_context = bdrv_get_aio_context(bs);
s->url = g_strdup(file);
state = curl_init_state(bs, s);
if (!state)
goto out_noclean;
// Get file size
s->accept_range = false;
curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
curl_header_cb);
curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
if (curl_easy_perform(state->curl))
goto out;
if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
goto out;
}
/* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
* know or the size is zero. From 7.19.4 CURL returns -1 if size is not
* known and zero if it is realy zero-length file. */
#if LIBCURL_VERSION_NUM >= 0x071304
if (d < 0) {
pstrcpy(state->errmsg, CURL_ERROR_SIZE,
"Server didn't report file size.");
goto out;
}
#else
if (d <= 0) {
pstrcpy(state->errmsg, CURL_ERROR_SIZE,
"Unknown file size or zero-length file.");
goto out;
}
#endif
s->len = (size_t)d;
if ((!strncasecmp(s->url, "http://", strlen("http://"))
|| !strncasecmp(s->url, "https://", strlen("https://")))
&& !s->accept_range) {
pstrcpy(state->errmsg, CURL_ERROR_SIZE,
"Server does not support 'range' (byte ranges).");
goto out;
}
DPRINTF("CURL: Size = %zd\n", s->len);
curl_clean_state(state);
curl_easy_cleanup(state->curl);
state->curl = NULL;
curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
qemu_opts_del(opts);
return 0;
out:
error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
curl_easy_cleanup(state->curl);
state->curl = NULL;
out_noclean:
g_free(s->cookie);
g_free(s->url);
qemu_opts_del(opts);
return -EINVAL;
}
static const AIOCBInfo curl_aiocb_info = {
.aiocb_size = sizeof(CURLAIOCB),
};
static void curl_readv_bh_cb(void *p)
{
CURLState *state;
int running;
CURLAIOCB *acb = p;
BDRVCURLState *s = acb->common.bs->opaque;
size_t start = acb->sector_num * BDRV_SECTOR_SIZE;
size_t end;
// In case we have the requested data already (e.g. read-ahead),
// we can just call the callback and be done.
switch (curl_find_buf(s, start, acb->nb_sectors * BDRV_SECTOR_SIZE, acb)) {
case FIND_RET_OK:
qemu_aio_unref(acb);
// fall through
case FIND_RET_WAIT:
return;
default:
break;
}
// No cache found, so let's start a new request
state = curl_init_state(acb->common.bs, s);
if (!state) {
acb->common.cb(acb->common.opaque, -EIO);
qemu_aio_unref(acb);
return;
}
acb->start = 0;
acb->end = MIN(acb->nb_sectors * BDRV_SECTOR_SIZE, s->len - start);
state->buf_off = 0;
g_free(state->orig_buf);
state->buf_start = start;
state->buf_len = MIN(acb->end + s->readahead_size, s->len - start);
end = start + state->buf_len - 1;
state->orig_buf = g_try_malloc(state->buf_len);
if (state->buf_len && state->orig_buf == NULL) {
curl_clean_state(state);
acb->common.cb(acb->common.opaque, -ENOMEM);
qemu_aio_unref(acb);
return;
}
state->acb[0] = acb;
snprintf(state->range, 127, "%zd-%zd", start, end);
DPRINTF("CURL (AIO): Reading %llu at %zd (%s)\n",
(acb->nb_sectors * BDRV_SECTOR_SIZE), start, state->range);
curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
curl_multi_add_handle(s->multi, state->curl);
/* Tell curl it needs to kick things off */
curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
}
static BlockAIOCB *curl_aio_readv(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque)
{
CURLAIOCB *acb;
acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
acb->qiov = qiov;
acb->sector_num = sector_num;
acb->nb_sectors = nb_sectors;
aio_bh_schedule_oneshot(bdrv_get_aio_context(bs), curl_readv_bh_cb, acb);
return &acb->common;
}
static void curl_close(BlockDriverState *bs)
{
BDRVCURLState *s = bs->opaque;
DPRINTF("CURL: Close\n");
curl_detach_aio_context(bs);
g_free(s->cookie);
g_free(s->url);
}
static int64_t curl_getlength(BlockDriverState *bs)
{
BDRVCURLState *s = bs->opaque;
return s->len;
}
static BlockDriver bdrv_http = {
.format_name = "http",
.protocol_name = "http",
.instance_size = sizeof(BDRVCURLState),
.bdrv_parse_filename = curl_parse_filename,
.bdrv_file_open = curl_open,
.bdrv_close = curl_close,
.bdrv_getlength = curl_getlength,
.bdrv_aio_readv = curl_aio_readv,
.bdrv_detach_aio_context = curl_detach_aio_context,
.bdrv_attach_aio_context = curl_attach_aio_context,
};
static BlockDriver bdrv_https = {
.format_name = "https",
.protocol_name = "https",
.instance_size = sizeof(BDRVCURLState),
.bdrv_parse_filename = curl_parse_filename,
.bdrv_file_open = curl_open,
.bdrv_close = curl_close,
.bdrv_getlength = curl_getlength,
.bdrv_aio_readv = curl_aio_readv,
.bdrv_detach_aio_context = curl_detach_aio_context,
.bdrv_attach_aio_context = curl_attach_aio_context,
};
static BlockDriver bdrv_ftp = {
.format_name = "ftp",
.protocol_name = "ftp",
.instance_size = sizeof(BDRVCURLState),
.bdrv_parse_filename = curl_parse_filename,
.bdrv_file_open = curl_open,
.bdrv_close = curl_close,
.bdrv_getlength = curl_getlength,
.bdrv_aio_readv = curl_aio_readv,
.bdrv_detach_aio_context = curl_detach_aio_context,
.bdrv_attach_aio_context = curl_attach_aio_context,
};
static BlockDriver bdrv_ftps = {
.format_name = "ftps",
.protocol_name = "ftps",
.instance_size = sizeof(BDRVCURLState),
.bdrv_parse_filename = curl_parse_filename,
.bdrv_file_open = curl_open,
.bdrv_close = curl_close,
.bdrv_getlength = curl_getlength,
.bdrv_aio_readv = curl_aio_readv,
.bdrv_detach_aio_context = curl_detach_aio_context,
.bdrv_attach_aio_context = curl_attach_aio_context,
};
static void curl_block_init(void)
{
bdrv_register(&bdrv_http);
bdrv_register(&bdrv_https);
bdrv_register(&bdrv_ftp);
bdrv_register(&bdrv_ftps);
}
block_init(curl_block_init);