diff options
Diffstat (limited to 'source3/libsmb/clireadwrite.c')
| -rw-r--r-- | source3/libsmb/clireadwrite.c | 178 |
1 files changed, 163 insertions, 15 deletions
diff --git a/source3/libsmb/clireadwrite.c b/source3/libsmb/clireadwrite.c index c618509f01..5aee8f18bd 100644 --- a/source3/libsmb/clireadwrite.c +++ b/source3/libsmb/clireadwrite.c @@ -444,27 +444,175 @@ NTSTATUS cli_pull(struct cli_state *cli, uint16_t fnum, return result; } -static NTSTATUS cli_read_sink(char *buf, size_t n, void *priv) +/**************************************************************************** +Issue a single SMBread and don't wait for a reply. +****************************************************************************/ + +static bool cli_issue_read(struct cli_state *cli, int fnum, off_t offset, + size_t size, int i) { - char **pbuf = (char **)priv; - memcpy(*pbuf, buf, n); - *pbuf += n; - return NT_STATUS_OK; + bool bigoffset = False; + + memset(cli->outbuf,'\0',smb_size); + memset(cli->inbuf,'\0',smb_size); + + if ((SMB_BIG_UINT)offset >> 32) + bigoffset = True; + + cli_set_message(cli->outbuf,bigoffset ? 12 : 10,0,True); + + SCVAL(cli->outbuf,smb_com,SMBreadX); + SSVAL(cli->outbuf,smb_tid,cli->cnum); + cli_setup_packet(cli); + + SCVAL(cli->outbuf,smb_vwv0,0xFF); + SSVAL(cli->outbuf,smb_vwv2,fnum); + SIVAL(cli->outbuf,smb_vwv3,offset); + SSVAL(cli->outbuf,smb_vwv5,size); + SSVAL(cli->outbuf,smb_vwv6,size); + SSVAL(cli->outbuf,smb_vwv7,(size >> 16)); + SSVAL(cli->outbuf,smb_mid,cli->mid + i); + + if (bigoffset) { + SIVAL(cli->outbuf,smb_vwv10,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff); + } + + return cli_send_smb(cli); } -ssize_t cli_read(struct cli_state *cli, int fnum, char *buf, - off_t offset, size_t size) +/**************************************************************************** + Read size bytes at offset offset using SMBreadX. +****************************************************************************/ + +ssize_t cli_read(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size) { - NTSTATUS status; - ssize_t ret; + char *p; + size_t size2; + size_t readsize; + ssize_t total = 0; + /* We can only do direct reads if not signing or encrypting. */ + bool direct_reads = !client_is_signing_on(cli) && !cli_encryption_on(cli); - status = cli_pull(cli, fnum, offset, size, size, - cli_read_sink, &buf, &ret); - if (!NT_STATUS_IS_OK(status)) { - cli_set_error(cli, status); - return -1; + if (size == 0) + return 0; + + /* + * Set readsize to the maximum size we can handle in one readX, + * rounded down to a multiple of 1024. + */ + + if (client_is_signing_on(cli) == false && + cli_encryption_on(cli) == false && + (cli->posix_capabilities & CIFS_UNIX_LARGE_READ_CAP)) { + readsize = CLI_SAMBA_MAX_POSIX_LARGE_READX_SIZE; + } else if (cli->capabilities & CAP_LARGE_READX) { + if (cli->is_samba) { + readsize = CLI_SAMBA_MAX_LARGE_READX_SIZE; + } else { + readsize = CLI_WINDOWS_MAX_LARGE_READX_SIZE; + } + } else { + readsize = (cli->max_xmit - (smb_size+32)) & ~1023; + } + + while (total < size) { + readsize = MIN(readsize, size-total); + + /* Issue a read and receive a reply */ + + if (!cli_issue_read(cli, fnum, offset, readsize, 0)) + return -1; + + if (direct_reads) { + if (!cli_receive_smb_readX_header(cli)) + return -1; + } else { + if (!cli_receive_smb(cli)) + return -1; + } + + /* Check for error. Make sure to check for DOS and NT + errors. */ + + if (cli_is_error(cli)) { + bool recoverable_error = False; + NTSTATUS status = NT_STATUS_OK; + uint8 eclass = 0; + uint32 ecode = 0; + + if (cli_is_nt_error(cli)) + status = cli_nt_error(cli); + else + cli_dos_error(cli, &eclass, &ecode); + + /* + * ERRDOS ERRmoredata or STATUS_MORE_ENRTIES is a + * recoverable error, plus we have valid data in the + * packet so don't error out here. + */ + + if ((eclass == ERRDOS && ecode == ERRmoredata) || + NT_STATUS_V(status) == NT_STATUS_V(STATUS_MORE_ENTRIES)) + recoverable_error = True; + + if (!recoverable_error) + return -1; + } + + /* size2 is the number of bytes the server returned. + * Might be zero. */ + size2 = SVAL(cli->inbuf, smb_vwv5); + size2 |= (((unsigned int)(SVAL(cli->inbuf, smb_vwv7))) << 16); + + if (size2 > readsize) { + DEBUG(5,("server returned more than we wanted!\n")); + return -1; + } else if (size2 < 0) { + DEBUG(5,("read return < 0!\n")); + return -1; + } + + if (size2) { + /* smb_vwv6 is the offset in the packet of the returned + * data bytes. Only valid if size2 != 0. */ + + if (!direct_reads) { + /* Copy data into buffer */ + p = smb_base(cli->inbuf) + SVAL(cli->inbuf,smb_vwv6); + memcpy(buf + total, p, size2); + } else { + /* Ensure the remaining data matches the return size. */ + ssize_t toread = smb_len_large(cli->inbuf) - SVAL(cli->inbuf,smb_vwv6); + + /* Ensure the size is correct. */ + if (toread != size2) { + DEBUG(5,("direct read logic fail toread (%d) != size2 (%u)\n", + (int)toread, (unsigned int)size2 )); + return -1; + } + + /* Read data directly into buffer */ + toread = cli_receive_smb_data(cli,buf+total,size2); + if (toread != size2) { + DEBUG(5,("direct read read failure toread (%d) != size2 (%u)\n", + (int)toread, (unsigned int)size2 )); + return -1; + } + } + } + + total += size2; + offset += size2; + + /* + * If the server returned less than we asked for we're at EOF. + */ + + if (size2 < readsize) + break; } - return ret; + + return total; } #if 0 /* relies on client_receive_smb(), now a static in libsmb/clientgen.c */ |