From b8cf945b3166c4394386f162a527c9950f396ce2 Mon Sep 17 00:00:00 2001 From: Eric Van Hensbergen Date: Fri, 9 Sep 2005 13:04:21 -0700 Subject: [PATCH] v9fs: 9P protocol implementation This part of the patch contains the 9P protocol functions. Signed-off-by: Eric Van Hensbergen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/9p/conv.c | 693 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 693 insertions(+) create mode 100644 fs/9p/conv.c (limited to 'fs/9p/conv.c') diff --git a/fs/9p/conv.c b/fs/9p/conv.c new file mode 100644 index 00000000000..1554731bd65 --- /dev/null +++ b/fs/9p/conv.c @@ -0,0 +1,693 @@ +/* + * linux/fs/9p/conv.c + * + * 9P protocol conversion functions + * + * Copyright (C) 2004 by Eric Van Hensbergen + * Copyright (C) 2002 by Ron Minnich + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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 +#include +#include +#include +#include + +#include "debug.h" +#include "v9fs.h" +#include "9p.h" +#include "conv.h" + +/* + * Buffer to help with string parsing + */ +struct cbuf { + unsigned char *sp; + unsigned char *p; + unsigned char *ep; +}; + +static inline void buf_init(struct cbuf *buf, void *data, int datalen) +{ + buf->sp = buf->p = data; + buf->ep = data + datalen; +} + +static inline int buf_check_overflow(struct cbuf *buf) +{ + return buf->p > buf->ep; +} + +static inline void buf_check_size(struct cbuf *buf, int len) +{ + if (buf->p+len > buf->ep) { + if (buf->p < buf->ep) { + eprintk(KERN_ERR, "buffer overflow\n"); + buf->p = buf->ep + 1; + } + } +} + +static inline void *buf_alloc(struct cbuf *buf, int len) +{ + void *ret = NULL; + + buf_check_size(buf, len); + ret = buf->p; + buf->p += len; + + return ret; +} + +static inline void buf_put_int8(struct cbuf *buf, u8 val) +{ + buf_check_size(buf, 1); + + buf->p[0] = val; + buf->p++; +} + +static inline void buf_put_int16(struct cbuf *buf, u16 val) +{ + buf_check_size(buf, 2); + + *(__le16 *) buf->p = cpu_to_le16(val); + buf->p += 2; +} + +static inline void buf_put_int32(struct cbuf *buf, u32 val) +{ + buf_check_size(buf, 4); + + *(__le32 *)buf->p = cpu_to_le32(val); + buf->p += 4; +} + +static inline void buf_put_int64(struct cbuf *buf, u64 val) +{ + buf_check_size(buf, 8); + + *(__le64 *)buf->p = cpu_to_le64(val); + buf->p += 8; +} + +static inline void buf_put_stringn(struct cbuf *buf, const char *s, u16 slen) +{ + buf_check_size(buf, slen + 2); + + buf_put_int16(buf, slen); + memcpy(buf->p, s, slen); + buf->p += slen; +} + +static inline void buf_put_string(struct cbuf *buf, const char *s) +{ + buf_put_stringn(buf, s, strlen(s)); +} + +static inline void buf_put_data(struct cbuf *buf, void *data, u32 datalen) +{ + buf_check_size(buf, datalen); + + memcpy(buf->p, data, datalen); + buf->p += datalen; +} + +static inline u8 buf_get_int8(struct cbuf *buf) +{ + u8 ret = 0; + + buf_check_size(buf, 1); + ret = buf->p[0]; + + buf->p++; + + return ret; +} + +static inline u16 buf_get_int16(struct cbuf *buf) +{ + u16 ret = 0; + + buf_check_size(buf, 2); + ret = le16_to_cpu(*(__le16 *)buf->p); + + buf->p += 2; + + return ret; +} + +static inline u32 buf_get_int32(struct cbuf *buf) +{ + u32 ret = 0; + + buf_check_size(buf, 4); + ret = le32_to_cpu(*(__le32 *)buf->p); + + buf->p += 4; + + return ret; +} + +static inline u64 buf_get_int64(struct cbuf *buf) +{ + u64 ret = 0; + + buf_check_size(buf, 8); + ret = le64_to_cpu(*(__le64 *)buf->p); + + buf->p += 8; + + return ret; +} + +static inline int +buf_get_string(struct cbuf *buf, char *data, unsigned int datalen) +{ + + u16 len = buf_get_int16(buf); + buf_check_size(buf, len); + if (len + 1 > datalen) + return 0; + + memcpy(data, buf->p, len); + data[len] = 0; + buf->p += len; + + return len + 1; +} + +static inline char *buf_get_stringb(struct cbuf *buf, struct cbuf *sbuf) +{ + char *ret = NULL; + int n = buf_get_string(buf, sbuf->p, sbuf->ep - sbuf->p); + + if (n > 0) { + ret = sbuf->p; + sbuf->p += n; + } + + return ret; +} + +static inline int buf_get_data(struct cbuf *buf, void *data, int datalen) +{ + buf_check_size(buf, datalen); + + memcpy(data, buf->p, datalen); + buf->p += datalen; + + return datalen; +} + +static inline void *buf_get_datab(struct cbuf *buf, struct cbuf *dbuf, + int datalen) +{ + char *ret = NULL; + int n = 0; + + buf_check_size(dbuf, datalen); + + n = buf_get_data(buf, dbuf->p, datalen); + + if (n > 0) { + ret = dbuf->p; + dbuf->p += n; + } + + return ret; +} + +/** + * v9fs_size_stat - calculate the size of a variable length stat struct + * @v9ses: session information + * @stat: metadata (stat) structure + * + */ + +static int v9fs_size_stat(struct v9fs_session_info *v9ses, + struct v9fs_stat *stat) +{ + int size = 0; + + if (stat == NULL) { + eprintk(KERN_ERR, "v9fs_size_stat: got a NULL stat pointer\n"); + return 0; + } + + size = /* 2 + *//* size[2] */ + 2 + /* type[2] */ + 4 + /* dev[4] */ + 1 + /* qid.type[1] */ + 4 + /* qid.vers[4] */ + 8 + /* qid.path[8] */ + 4 + /* mode[4] */ + 4 + /* atime[4] */ + 4 + /* mtime[4] */ + 8 + /* length[8] */ + 8; /* minimum sum of string lengths */ + + if (stat->name) + size += strlen(stat->name); + if (stat->uid) + size += strlen(stat->uid); + if (stat->gid) + size += strlen(stat->gid); + if (stat->muid) + size += strlen(stat->muid); + + if (v9ses->extended) { + size += 4 + /* n_uid[4] */ + 4 + /* n_gid[4] */ + 4 + /* n_muid[4] */ + 2; /* string length of extension[4] */ + if (stat->extension) + size += strlen(stat->extension); + } + + return size; +} + +/** + * serialize_stat - safely format a stat structure for transmission + * @v9ses: session info + * @stat: metadata (stat) structure + * @bufp: buffer to serialize structure into + * + */ + +static int +serialize_stat(struct v9fs_session_info *v9ses, struct v9fs_stat *stat, + struct cbuf *bufp) +{ + buf_put_int16(bufp, stat->size); + buf_put_int16(bufp, stat->type); + buf_put_int32(bufp, stat->dev); + buf_put_int8(bufp, stat->qid.type); + buf_put_int32(bufp, stat->qid.version); + buf_put_int64(bufp, stat->qid.path); + buf_put_int32(bufp, stat->mode); + buf_put_int32(bufp, stat->atime); + buf_put_int32(bufp, stat->mtime); + buf_put_int64(bufp, stat->length); + + buf_put_string(bufp, stat->name); + buf_put_string(bufp, stat->uid); + buf_put_string(bufp, stat->gid); + buf_put_string(bufp, stat->muid); + + if (v9ses->extended) { + buf_put_string(bufp, stat->extension); + buf_put_int32(bufp, stat->n_uid); + buf_put_int32(bufp, stat->n_gid); + buf_put_int32(bufp, stat->n_muid); + } + + if (buf_check_overflow(bufp)) + return 0; + + return stat->size; +} + +/** + * deserialize_stat - safely decode a recieved metadata (stat) structure + * @v9ses: session info + * @bufp: buffer to deserialize + * @stat: metadata (stat) structure + * @dbufp: buffer to deserialize variable strings into + * + */ + +static inline int +deserialize_stat(struct v9fs_session_info *v9ses, struct cbuf *bufp, + struct v9fs_stat *stat, struct cbuf *dbufp) +{ + + stat->size = buf_get_int16(bufp); + stat->type = buf_get_int16(bufp); + stat->dev = buf_get_int32(bufp); + stat->qid.type = buf_get_int8(bufp); + stat->qid.version = buf_get_int32(bufp); + stat->qid.path = buf_get_int64(bufp); + stat->mode = buf_get_int32(bufp); + stat->atime = buf_get_int32(bufp); + stat->mtime = buf_get_int32(bufp); + stat->length = buf_get_int64(bufp); + stat->name = buf_get_stringb(bufp, dbufp); + stat->uid = buf_get_stringb(bufp, dbufp); + stat->gid = buf_get_stringb(bufp, dbufp); + stat->muid = buf_get_stringb(bufp, dbufp); + + if (v9ses->extended) { + stat->extension = buf_get_stringb(bufp, dbufp); + stat->n_uid = buf_get_int32(bufp); + stat->n_gid = buf_get_int32(bufp); + stat->n_muid = buf_get_int32(bufp); + } + + if (buf_check_overflow(bufp) || buf_check_overflow(dbufp)) + return 0; + + return stat->size + 2; +} + +/** + * deserialize_statb - wrapper for decoding a received metadata structure + * @v9ses: session info + * @bufp: buffer to deserialize + * @dbufp: buffer to deserialize variable strings into + * + */ + +static inline struct v9fs_stat *deserialize_statb(struct v9fs_session_info + *v9ses, struct cbuf *bufp, + struct cbuf *dbufp) +{ + struct v9fs_stat *ret = buf_alloc(dbufp, sizeof(struct v9fs_stat)); + + if (ret) { + int n = deserialize_stat(v9ses, bufp, ret, dbufp); + if (n <= 0) + return NULL; + } + + return ret; +} + +/** + * v9fs_deserialize_stat - decode a received metadata structure + * @v9ses: session info + * @buf: buffer to deserialize + * @buflen: length of received buffer + * @stat: metadata structure to decode into + * @statlen: length of destination metadata structure + * + */ + +int +v9fs_deserialize_stat(struct v9fs_session_info *v9ses, void *buf, + u32 buflen, struct v9fs_stat *stat, u32 statlen) +{ + struct cbuf buffer; + struct cbuf *bufp = &buffer; + struct cbuf dbuffer; + struct cbuf *dbufp = &dbuffer; + + buf_init(bufp, buf, buflen); + buf_init(dbufp, (char *)stat + sizeof(struct v9fs_stat), + statlen - sizeof(struct v9fs_stat)); + + return deserialize_stat(v9ses, bufp, stat, dbufp); +} + +static inline int +v9fs_size_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall) +{ + int size = 4 + 1 + 2; /* size[4] msg[1] tag[2] */ + int i = 0; + + switch (fcall->id) { + default: + eprintk(KERN_ERR, "bad msg type %d\n", fcall->id); + return 0; + case TVERSION: /* msize[4] version[s] */ + size += 4 + 2 + strlen(fcall->params.tversion.version); + break; + case TAUTH: /* afid[4] uname[s] aname[s] */ + size += 4 + 2 + strlen(fcall->params.tauth.uname) + + 2 + strlen(fcall->params.tauth.aname); + break; + case TFLUSH: /* oldtag[2] */ + size += 2; + break; + case TATTACH: /* fid[4] afid[4] uname[s] aname[s] */ + size += 4 + 4 + 2 + strlen(fcall->params.tattach.uname) + + 2 + strlen(fcall->params.tattach.aname); + break; + case TWALK: /* fid[4] newfid[4] nwname[2] nwname*(wname[s]) */ + size += 4 + 4 + 2; + /* now compute total for the array of names */ + for (i = 0; i < fcall->params.twalk.nwname; i++) + size += 2 + strlen(fcall->params.twalk.wnames[i]); + break; + case TOPEN: /* fid[4] mode[1] */ + size += 4 + 1; + break; + case TCREATE: /* fid[4] name[s] perm[4] mode[1] */ + size += 4 + 2 + strlen(fcall->params.tcreate.name) + 4 + 1; + break; + case TREAD: /* fid[4] offset[8] count[4] */ + size += 4 + 8 + 4; + break; + case TWRITE: /* fid[4] offset[8] count[4] data[count] */ + size += 4 + 8 + 4 + fcall->params.twrite.count; + break; + case TCLUNK: /* fid[4] */ + size += 4; + break; + case TREMOVE: /* fid[4] */ + size += 4; + break; + case TSTAT: /* fid[4] */ + size += 4; + break; + case TWSTAT: /* fid[4] stat[n] */ + fcall->params.twstat.stat->size = + v9fs_size_stat(v9ses, fcall->params.twstat.stat); + size += 4 + 2 + 2 + fcall->params.twstat.stat->size; + } + return size; +} + +/* + * v9fs_serialize_fcall - marshall fcall struct into a packet + * @v9ses: session information + * @fcall: structure to convert + * @data: buffer to serialize fcall into + * @datalen: length of buffer to serialize fcall into + * + */ + +int +v9fs_serialize_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall, + void *data, u32 datalen) +{ + int i = 0; + struct v9fs_stat *stat = NULL; + struct cbuf buffer; + struct cbuf *bufp = &buffer; + + buf_init(bufp, data, datalen); + + if (!fcall) { + eprintk(KERN_ERR, "no fcall\n"); + return -EINVAL; + } + + fcall->size = v9fs_size_fcall(v9ses, fcall); + + buf_put_int32(bufp, fcall->size); + buf_put_int8(bufp, fcall->id); + buf_put_int16(bufp, fcall->tag); + + dprintk(DEBUG_CONV, "size %d id %d tag %d\n", fcall->size, fcall->id, + fcall->tag); + + /* now encode it */ + switch (fcall->id) { + default: + eprintk(KERN_ERR, "bad msg type: %d\n", fcall->id); + return -EPROTO; + case TVERSION: + buf_put_int32(bufp, fcall->params.tversion.msize); + buf_put_string(bufp, fcall->params.tversion.version); + break; + case TAUTH: + buf_put_int32(bufp, fcall->params.tauth.afid); + buf_put_string(bufp, fcall->params.tauth.uname); + buf_put_string(bufp, fcall->params.tauth.aname); + break; + case TFLUSH: + buf_put_int16(bufp, fcall->params.tflush.oldtag); + break; + case TATTACH: + buf_put_int32(bufp, fcall->params.tattach.fid); + buf_put_int32(bufp, fcall->params.tattach.afid); + buf_put_string(bufp, fcall->params.tattach.uname); + buf_put_string(bufp, fcall->params.tattach.aname); + break; + case TWALK: + buf_put_int32(bufp, fcall->params.twalk.fid); + buf_put_int32(bufp, fcall->params.twalk.newfid); + buf_put_int16(bufp, fcall->params.twalk.nwname); + for (i = 0; i < fcall->params.twalk.nwname; i++) + buf_put_string(bufp, fcall->params.twalk.wnames[i]); + break; + case TOPEN: + buf_put_int32(bufp, fcall->params.topen.fid); + buf_put_int8(bufp, fcall->params.topen.mode); + break; + case TCREATE: + buf_put_int32(bufp, fcall->params.tcreate.fid); + buf_put_string(bufp, fcall->params.tcreate.name); + buf_put_int32(bufp, fcall->params.tcreate.perm); + buf_put_int8(bufp, fcall->params.tcreate.mode); + break; + case TREAD: + buf_put_int32(bufp, fcall->params.tread.fid); + buf_put_int64(bufp, fcall->params.tread.offset); + buf_put_int32(bufp, fcall->params.tread.count); + break; + case TWRITE: + buf_put_int32(bufp, fcall->params.twrite.fid); + buf_put_int64(bufp, fcall->params.twrite.offset); + buf_put_int32(bufp, fcall->params.twrite.count); + buf_put_data(bufp, fcall->params.twrite.data, + fcall->params.twrite.count); + break; + case TCLUNK: + buf_put_int32(bufp, fcall->params.tclunk.fid); + break; + case TREMOVE: + buf_put_int32(bufp, fcall->params.tremove.fid); + break; + case TSTAT: + buf_put_int32(bufp, fcall->params.tstat.fid); + break; + case TWSTAT: + buf_put_int32(bufp, fcall->params.twstat.fid); + stat = fcall->params.twstat.stat; + + buf_put_int16(bufp, stat->size + 2); + serialize_stat(v9ses, stat, bufp); + break; + } + + if (buf_check_overflow(bufp)) + return -EIO; + + return fcall->size; +} + +/** + * deserialize_fcall - unmarshal a response + * @v9ses: session information + * @msgsize: size of rcall message + * @buf: recieved buffer + * @buflen: length of received buffer + * @rcall: fcall structure to populate + * @rcalllen: length of fcall structure to populate + * + */ + +int +v9fs_deserialize_fcall(struct v9fs_session_info *v9ses, u32 msgsize, + void *buf, u32 buflen, struct v9fs_fcall *rcall, + int rcalllen) +{ + + struct cbuf buffer; + struct cbuf *bufp = &buffer; + struct cbuf dbuffer; + struct cbuf *dbufp = &dbuffer; + int i = 0; + + buf_init(bufp, buf, buflen); + buf_init(dbufp, (char *)rcall + sizeof(struct v9fs_fcall), + rcalllen - sizeof(struct v9fs_fcall)); + + rcall->size = msgsize; + rcall->id = buf_get_int8(bufp); + rcall->tag = buf_get_int16(bufp); + + dprintk(DEBUG_CONV, "size %d id %d tag %d\n", rcall->size, rcall->id, + rcall->tag); + switch (rcall->id) { + default: + eprintk(KERN_ERR, "unknown message type: %d\n", rcall->id); + return -EPROTO; + case RVERSION: + rcall->params.rversion.msize = buf_get_int32(bufp); + rcall->params.rversion.version = buf_get_stringb(bufp, dbufp); + break; + case RFLUSH: + break; + case RATTACH: + rcall->params.rattach.qid.type = buf_get_int8(bufp); + rcall->params.rattach.qid.version = buf_get_int32(bufp); + rcall->params.rattach.qid.path = buf_get_int64(bufp); + break; + case RWALK: + rcall->params.rwalk.nwqid = buf_get_int16(bufp); + rcall->params.rwalk.wqids = buf_alloc(bufp, + rcall->params.rwalk.nwqid * sizeof(struct v9fs_qid)); + if (rcall->params.rwalk.wqids) + for (i = 0; i < rcall->params.rwalk.nwqid; i++) { + rcall->params.rwalk.wqids[i].type = + buf_get_int8(bufp); + rcall->params.rwalk.wqids[i].version = + buf_get_int16(bufp); + rcall->params.rwalk.wqids[i].path = + buf_get_int64(bufp); + } + break; + case ROPEN: + rcall->params.ropen.qid.type = buf_get_int8(bufp); + rcall->params.ropen.qid.version = buf_get_int32(bufp); + rcall->params.ropen.qid.path = buf_get_int64(bufp); + rcall->params.ropen.iounit = buf_get_int32(bufp); + break; + case RCREATE: + rcall->params.rcreate.qid.type = buf_get_int8(bufp); + rcall->params.rcreate.qid.version = buf_get_int32(bufp); + rcall->params.rcreate.qid.path = buf_get_int64(bufp); + rcall->params.rcreate.iounit = buf_get_int32(bufp); + break; + case RREAD: + rcall->params.rread.count = buf_get_int32(bufp); + rcall->params.rread.data = buf_get_datab(bufp, dbufp, + rcall->params.rread.count); + break; + case RWRITE: + rcall->params.rwrite.count = buf_get_int32(bufp); + break; + case RCLUNK: + break; + case RREMOVE: + break; + case RSTAT: + buf_get_int16(bufp); + rcall->params.rstat.stat = + deserialize_statb(v9ses, bufp, dbufp); + break; + case RWSTAT: + break; + case RERROR: + rcall->params.rerror.error = buf_get_stringb(bufp, dbufp); + if (v9ses->extended) + rcall->params.rerror.errno = buf_get_int16(bufp); + break; + } + + if (buf_check_overflow(bufp) || buf_check_overflow(dbufp)) + return -EIO; + + return rcall->size; +} -- cgit v1.2.3