diff options
Diffstat (limited to 'net/9p/protocol.c')
| -rw-r--r-- | net/9p/protocol.c | 635 |
1 files changed, 635 insertions, 0 deletions
diff --git a/net/9p/protocol.c b/net/9p/protocol.c new file mode 100644 index 000000000..ef0a82dbb --- /dev/null +++ b/net/9p/protocol.c @@ -0,0 +1,635 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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. + */ + +#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 ***); + + *wnames = NULL; + + errcode = p9pdu_readf(pdu, proto_version, + "w", nwname); + if (!errcode) { + *wnames = + kmalloc_array(*nwname, + sizeof(char *), + GFP_NOFS); + if (!*wnames) + errcode = -ENOMEM; + else + (*wnames)[0] = NULL; + } + + if (!errcode) { + int i; + + for (i = 0; i < *nwname; i++) { + errcode = + p9pdu_readf(pdu, + proto_version, + "s", + &(*wnames)[i]); + if (errcode) { + (*wnames)[i] = NULL; + break; + } + } + } + + if (errcode) { + if (*wnames) { + int i; + + for (i = 0; i < *nwname; i++) { + if (!(*wnames)[i]) + break; + 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); |