| /* |
| * 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(&pdu->sdata[pdu->size], len, &i) != len) |
| 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 = -EFAULT; |
| 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(sizeof(char *) * *nwname, |
| 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(*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); |