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-rw-r--r--net/9p/protocol.c641
1 files changed, 641 insertions, 0 deletions
diff --git a/net/9p/protocol.c b/net/9p/protocol.c
new file mode 100644
index 000000000..462ba144c
--- /dev/null
+++ b/net/9p/protocol.c
@@ -0,0 +1,641 @@
+/*
+ * net/9p/protocol.c
+ *
+ * 9P Protocol Support Code
+ *
+ * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ * Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2008 by IBM, Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to:
+ * Free Software Foundation
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA 02111-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include "protocol.h"
+
+#include <trace/events/9p.h>
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+
+void p9stat_free(struct p9_wstat *stbuf)
+{
+ kfree(stbuf->name);
+ stbuf->name = NULL;
+ kfree(stbuf->uid);
+ stbuf->uid = NULL;
+ kfree(stbuf->gid);
+ stbuf->gid = NULL;
+ kfree(stbuf->muid);
+ stbuf->muid = NULL;
+ kfree(stbuf->extension);
+ stbuf->extension = NULL;
+}
+EXPORT_SYMBOL(p9stat_free);
+
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
+{
+ size_t len = min(pdu->size - pdu->offset, size);
+ memcpy(data, &pdu->sdata[pdu->offset], len);
+ pdu->offset += len;
+ return size - len;
+}
+
+static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
+{
+ size_t len = min(pdu->capacity - pdu->size, size);
+ memcpy(&pdu->sdata[pdu->size], data, len);
+ pdu->size += len;
+ return size - len;
+}
+
+static size_t
+pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)
+{
+ size_t len = min(pdu->capacity - pdu->size, size);
+ struct iov_iter i = *from;
+ if (!copy_from_iter_full(&pdu->sdata[pdu->size], len, &i))
+ len = 0;
+
+ pdu->size += len;
+ return size - len;
+}
+
+/*
+ b - int8_t
+ w - int16_t
+ d - int32_t
+ q - int64_t
+ s - string
+ u - numeric uid
+ g - numeric gid
+ S - stat
+ Q - qid
+ D - data blob (int32_t size followed by void *, results are not freed)
+ T - array of strings (int16_t count, followed by strings)
+ R - array of qids (int16_t count, followed by qids)
+ A - stat for 9p2000.L (p9_stat_dotl)
+ ? - if optional = 1, continue parsing
+*/
+
+static int
+p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
+ va_list ap)
+{
+ const char *ptr;
+ int errcode = 0;
+
+ for (ptr = fmt; *ptr; ptr++) {
+ switch (*ptr) {
+ case 'b':{
+ int8_t *val = va_arg(ap, int8_t *);
+ if (pdu_read(pdu, val, sizeof(*val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ }
+ break;
+ case 'w':{
+ int16_t *val = va_arg(ap, int16_t *);
+ __le16 le_val;
+ if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = le16_to_cpu(le_val);
+ }
+ break;
+ case 'd':{
+ int32_t *val = va_arg(ap, int32_t *);
+ __le32 le_val;
+ if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = le32_to_cpu(le_val);
+ }
+ break;
+ case 'q':{
+ int64_t *val = va_arg(ap, int64_t *);
+ __le64 le_val;
+ if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = le64_to_cpu(le_val);
+ }
+ break;
+ case 's':{
+ char **sptr = va_arg(ap, char **);
+ uint16_t len;
+
+ errcode = p9pdu_readf(pdu, proto_version,
+ "w", &len);
+ if (errcode)
+ break;
+
+ *sptr = kmalloc(len + 1, GFP_NOFS);
+ if (*sptr == NULL) {
+ errcode = -ENOMEM;
+ break;
+ }
+ if (pdu_read(pdu, *sptr, len)) {
+ errcode = -EFAULT;
+ kfree(*sptr);
+ *sptr = NULL;
+ } else
+ (*sptr)[len] = 0;
+ }
+ break;
+ case 'u': {
+ kuid_t *uid = va_arg(ap, kuid_t *);
+ __le32 le_val;
+ if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *uid = make_kuid(&init_user_ns,
+ le32_to_cpu(le_val));
+ } break;
+ case 'g': {
+ kgid_t *gid = va_arg(ap, kgid_t *);
+ __le32 le_val;
+ if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *gid = make_kgid(&init_user_ns,
+ le32_to_cpu(le_val));
+ } break;
+ case 'Q':{
+ struct p9_qid *qid =
+ va_arg(ap, struct p9_qid *);
+
+ errcode = p9pdu_readf(pdu, proto_version, "bdq",
+ &qid->type, &qid->version,
+ &qid->path);
+ }
+ break;
+ case 'S':{
+ struct p9_wstat *stbuf =
+ va_arg(ap, struct p9_wstat *);
+
+ memset(stbuf, 0, sizeof(struct p9_wstat));
+ stbuf->n_uid = stbuf->n_muid = INVALID_UID;
+ stbuf->n_gid = INVALID_GID;
+
+ errcode =
+ p9pdu_readf(pdu, proto_version,
+ "wwdQdddqssss?sugu",
+ &stbuf->size, &stbuf->type,
+ &stbuf->dev, &stbuf->qid,
+ &stbuf->mode, &stbuf->atime,
+ &stbuf->mtime, &stbuf->length,
+ &stbuf->name, &stbuf->uid,
+ &stbuf->gid, &stbuf->muid,
+ &stbuf->extension,
+ &stbuf->n_uid, &stbuf->n_gid,
+ &stbuf->n_muid);
+ if (errcode)
+ p9stat_free(stbuf);
+ }
+ break;
+ case 'D':{
+ uint32_t *count = va_arg(ap, uint32_t *);
+ void **data = va_arg(ap, void **);
+
+ errcode =
+ p9pdu_readf(pdu, proto_version, "d", count);
+ if (!errcode) {
+ *count =
+ min_t(uint32_t, *count,
+ pdu->size - pdu->offset);
+ *data = &pdu->sdata[pdu->offset];
+ }
+ }
+ break;
+ case 'T':{
+ uint16_t *nwname = va_arg(ap, uint16_t *);
+ char ***wnames = va_arg(ap, char ***);
+
+ errcode = p9pdu_readf(pdu, proto_version,
+ "w", nwname);
+ if (!errcode) {
+ *wnames =
+ kmalloc_array(*nwname,
+ sizeof(char *),
+ GFP_NOFS);
+ if (!*wnames)
+ errcode = -ENOMEM;
+ }
+
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < *nwname; i++) {
+ errcode =
+ p9pdu_readf(pdu,
+ proto_version,
+ "s",
+ &(*wnames)[i]);
+ if (errcode)
+ break;
+ }
+ }
+
+ if (errcode) {
+ if (*wnames) {
+ int i;
+
+ for (i = 0; i < *nwname; i++)
+ kfree((*wnames)[i]);
+ }
+ kfree(*wnames);
+ *wnames = NULL;
+ }
+ }
+ break;
+ case 'R':{
+ uint16_t *nwqid = va_arg(ap, uint16_t *);
+ struct p9_qid **wqids =
+ va_arg(ap, struct p9_qid **);
+
+ *wqids = NULL;
+
+ errcode =
+ p9pdu_readf(pdu, proto_version, "w", nwqid);
+ if (!errcode) {
+ *wqids =
+ kmalloc_array(*nwqid,
+ sizeof(struct p9_qid),
+ GFP_NOFS);
+ if (*wqids == NULL)
+ errcode = -ENOMEM;
+ }
+
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < *nwqid; i++) {
+ errcode =
+ p9pdu_readf(pdu,
+ proto_version,
+ "Q",
+ &(*wqids)[i]);
+ if (errcode)
+ break;
+ }
+ }
+
+ if (errcode) {
+ kfree(*wqids);
+ *wqids = NULL;
+ }
+ }
+ break;
+ case 'A': {
+ struct p9_stat_dotl *stbuf =
+ va_arg(ap, struct p9_stat_dotl *);
+
+ memset(stbuf, 0, sizeof(struct p9_stat_dotl));
+ errcode =
+ p9pdu_readf(pdu, proto_version,
+ "qQdugqqqqqqqqqqqqqqq",
+ &stbuf->st_result_mask,
+ &stbuf->qid,
+ &stbuf->st_mode,
+ &stbuf->st_uid, &stbuf->st_gid,
+ &stbuf->st_nlink,
+ &stbuf->st_rdev, &stbuf->st_size,
+ &stbuf->st_blksize, &stbuf->st_blocks,
+ &stbuf->st_atime_sec,
+ &stbuf->st_atime_nsec,
+ &stbuf->st_mtime_sec,
+ &stbuf->st_mtime_nsec,
+ &stbuf->st_ctime_sec,
+ &stbuf->st_ctime_nsec,
+ &stbuf->st_btime_sec,
+ &stbuf->st_btime_nsec,
+ &stbuf->st_gen,
+ &stbuf->st_data_version);
+ }
+ break;
+ case '?':
+ if ((proto_version != p9_proto_2000u) &&
+ (proto_version != p9_proto_2000L))
+ return 0;
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ if (errcode)
+ break;
+ }
+
+ return errcode;
+}
+
+int
+p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+ va_list ap)
+{
+ const char *ptr;
+ int errcode = 0;
+
+ for (ptr = fmt; *ptr; ptr++) {
+ switch (*ptr) {
+ case 'b':{
+ int8_t val = va_arg(ap, int);
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'w':{
+ __le16 val = cpu_to_le16(va_arg(ap, int));
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'd':{
+ __le32 val = cpu_to_le32(va_arg(ap, int32_t));
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'q':{
+ __le64 val = cpu_to_le64(va_arg(ap, int64_t));
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 's':{
+ const char *sptr = va_arg(ap, const char *);
+ uint16_t len = 0;
+ if (sptr)
+ len = min_t(size_t, strlen(sptr),
+ USHRT_MAX);
+
+ errcode = p9pdu_writef(pdu, proto_version,
+ "w", len);
+ if (!errcode && pdu_write(pdu, sptr, len))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'u': {
+ kuid_t uid = va_arg(ap, kuid_t);
+ __le32 val = cpu_to_le32(
+ from_kuid(&init_user_ns, uid));
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ } break;
+ case 'g': {
+ kgid_t gid = va_arg(ap, kgid_t);
+ __le32 val = cpu_to_le32(
+ from_kgid(&init_user_ns, gid));
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ } break;
+ case 'Q':{
+ const struct p9_qid *qid =
+ va_arg(ap, const struct p9_qid *);
+ errcode =
+ p9pdu_writef(pdu, proto_version, "bdq",
+ qid->type, qid->version,
+ qid->path);
+ } break;
+ case 'S':{
+ const struct p9_wstat *stbuf =
+ va_arg(ap, const struct p9_wstat *);
+ errcode =
+ p9pdu_writef(pdu, proto_version,
+ "wwdQdddqssss?sugu",
+ stbuf->size, stbuf->type,
+ stbuf->dev, &stbuf->qid,
+ stbuf->mode, stbuf->atime,
+ stbuf->mtime, stbuf->length,
+ stbuf->name, stbuf->uid,
+ stbuf->gid, stbuf->muid,
+ stbuf->extension, stbuf->n_uid,
+ stbuf->n_gid, stbuf->n_muid);
+ } break;
+ case 'V':{
+ uint32_t count = va_arg(ap, uint32_t);
+ struct iov_iter *from =
+ va_arg(ap, struct iov_iter *);
+ errcode = p9pdu_writef(pdu, proto_version, "d",
+ count);
+ if (!errcode && pdu_write_u(pdu, from, count))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'T':{
+ uint16_t nwname = va_arg(ap, int);
+ const char **wnames = va_arg(ap, const char **);
+
+ errcode = p9pdu_writef(pdu, proto_version, "w",
+ nwname);
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < nwname; i++) {
+ errcode =
+ p9pdu_writef(pdu,
+ proto_version,
+ "s",
+ wnames[i]);
+ if (errcode)
+ break;
+ }
+ }
+ }
+ break;
+ case 'R':{
+ uint16_t nwqid = va_arg(ap, int);
+ struct p9_qid *wqids =
+ va_arg(ap, struct p9_qid *);
+
+ errcode = p9pdu_writef(pdu, proto_version, "w",
+ nwqid);
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < nwqid; i++) {
+ errcode =
+ p9pdu_writef(pdu,
+ proto_version,
+ "Q",
+ &wqids[i]);
+ if (errcode)
+ break;
+ }
+ }
+ }
+ break;
+ case 'I':{
+ struct p9_iattr_dotl *p9attr = va_arg(ap,
+ struct p9_iattr_dotl *);
+
+ errcode = p9pdu_writef(pdu, proto_version,
+ "ddugqqqqq",
+ p9attr->valid,
+ p9attr->mode,
+ p9attr->uid,
+ p9attr->gid,
+ p9attr->size,
+ p9attr->atime_sec,
+ p9attr->atime_nsec,
+ p9attr->mtime_sec,
+ p9attr->mtime_nsec);
+ }
+ break;
+ case '?':
+ if ((proto_version != p9_proto_2000u) &&
+ (proto_version != p9_proto_2000L))
+ return 0;
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ if (errcode)
+ break;
+ }
+
+ return errcode;
+}
+
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
+{
+ struct p9_fcall fake_pdu;
+ int ret;
+
+ fake_pdu.size = len;
+ fake_pdu.capacity = len;
+ fake_pdu.sdata = buf;
+ fake_pdu.offset = 0;
+
+ ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
+ if (ret) {
+ p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
+ trace_9p_protocol_dump(clnt, &fake_pdu);
+ return ret;
+ }
+
+ return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9stat_read);
+
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
+{
+ pdu->id = type;
+ return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
+}
+
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
+{
+ int size = pdu->size;
+ int err;
+
+ pdu->size = 0;
+ err = p9pdu_writef(pdu, 0, "d", size);
+ pdu->size = size;
+
+ trace_9p_protocol_dump(clnt, pdu);
+ p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
+ pdu->size, pdu->id, pdu->tag);
+
+ return err;
+}
+
+void p9pdu_reset(struct p9_fcall *pdu)
+{
+ pdu->offset = 0;
+ pdu->size = 0;
+}
+
+int p9dirent_read(struct p9_client *clnt, char *buf, int len,
+ struct p9_dirent *dirent)
+{
+ struct p9_fcall fake_pdu;
+ int ret;
+ char *nameptr;
+
+ fake_pdu.size = len;
+ fake_pdu.capacity = len;
+ fake_pdu.sdata = buf;
+ fake_pdu.offset = 0;
+
+ ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
+ &dirent->d_off, &dirent->d_type, &nameptr);
+ if (ret) {
+ p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
+ trace_9p_protocol_dump(clnt, &fake_pdu);
+ return ret;
+ }
+
+ ret = strscpy(dirent->d_name, nameptr, sizeof(dirent->d_name));
+ if (ret < 0) {
+ p9_debug(P9_DEBUG_ERROR,
+ "On the wire dirent name too long: %s\n",
+ nameptr);
+ kfree(nameptr);
+ return ret;
+ }
+ kfree(nameptr);
+
+ return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9dirent_read);