From fb6527468c26d18c800580f765ae8c8ea8edb88b Mon Sep 17 00:00:00 2001 From: Michael Buckley Date: Thu, 9 May 2024 15:39:28 -0700 Subject: [PATCH] sftp: implement posix-rename@openssh.com Add a new function `libssh2_sftp_posix_rename_ex()` and `libssh2_sftp_posix_rename()`, which implement the posix-rename@openssh.com extension. If the server does not support this extension, the function returns `LIBSSH2_FX_OP_UNSUPPORTED` and it's up to the user to recover, possibly by calling `libssh2_sftp_rename()`. Co-authored-by: Viktor Szakats (bump to size_t) Closes #1386 --- docs/Makefile.am | 2 + docs/libssh2_sftp_posix_rename.3 | 24 +++++ docs/libssh2_sftp_posix_rename_ex.3 | 58 ++++++++++ include/libssh2_sftp.h | 9 ++ src/sftp.c | 157 +++++++++++++++++++++++++++- src/sftp.h | 7 +- 6 files changed, 254 insertions(+), 3 deletions(-) create mode 100644 docs/libssh2_sftp_posix_rename.3 create mode 100644 docs/libssh2_sftp_posix_rename_ex.3 diff --git a/docs/Makefile.am b/docs/Makefile.am index 260e859f..f330b601 100644 --- a/docs/Makefile.am +++ b/docs/Makefile.am @@ -144,6 +144,8 @@ dist_man_MANS = \ libssh2_sftp_open_ex_r.3 \ libssh2_sftp_open_r.3 \ libssh2_sftp_opendir.3 \ + libssh2_sftp_posix_rename.3 \ + libssh2_sftp_posix_rename_ex.3 \ libssh2_sftp_read.3 \ libssh2_sftp_readdir.3 \ libssh2_sftp_readdir_ex.3 \ diff --git a/docs/libssh2_sftp_posix_rename.3 b/docs/libssh2_sftp_posix_rename.3 new file mode 100644 index 00000000..95cbd4de --- /dev/null +++ b/docs/libssh2_sftp_posix_rename.3 @@ -0,0 +1,24 @@ +.\" Copyright (C) The libssh2 project and its contributors. +.\" SPDX-License-Identifier: BSD-3-Clause +.TH libssh2_sftp_posix_rename 3 "9 May 2024" "libssh2 1.11.1" "libssh2" +.SH NAME +libssh2_sftp_rename - convenience macro for \fIlibssh2_sftp_posix_rename_ex(3)\fP calls +.SH SYNOPSIS +.nf +#include +#include + +int +libssh2_sftp_posix_rename(LIBSSH2_SFTP *sftp, + const char *source_filename, + const char *destination_filename); +.fi +.SH DESCRIPTION +This is a macro defined in a public libssh2 header file that is using the +underlying function \fIlibssh2_sftp_posix_rename_ex(3)\fP. +.SH RETURN VALUE +See \fIlibssh2_sftp_posix_rename_ex(3)\fP +.SH ERRORS +See \fIlibssh2_sftp_posix_rename_ex(3)\fP +.SH SEE ALSO +.BR libssh2_sftp_posix_rename_ex(3) diff --git a/docs/libssh2_sftp_posix_rename_ex.3 b/docs/libssh2_sftp_posix_rename_ex.3 new file mode 100644 index 00000000..03b6c39f --- /dev/null +++ b/docs/libssh2_sftp_posix_rename_ex.3 @@ -0,0 +1,58 @@ +.\" Copyright (C) The libssh2 project and its contributors. +.\" SPDX-License-Identifier: BSD-3-Clause +.TH libssh2_sftp_posix_rename_ex 3 "9 May 2024" "libssh2 1.11.1" "libssh2" +.SH NAME +libssh2_sftp_posix_rename_ex - rename an SFTP file using POSIX semantics +.SH SYNOPSIS +.nf +#include +#include + +int +libssh2_sftp_posix_rename_ex(LIBSSH2_SFTP *sftp, + const char *source_filename, + size_t source_filename_len, + const char *dest_filename, + size_t dest_filename_len); +.fi +.SH DESCRIPTION +\fIsftp\fP - SFTP instance as returned by +.BR libssh2_sftp_init(3) + +\fIsourcefile\fP - Path and name of the existing filesystem entry + +\fIsourcefile_len\fP - Length of the path and name of the existing +filesystem entry + +\fIdestfile\fP - Path and name of the target filesystem entry + +\fIdestfile_len\fP - Length of the path and name of the target +filesystem entry + +This function implements the posix-rename@openssh.com extension, which is +useful when, for example, moving files across filesystems on a remote server. +SSH_FXP_RENAME does not specify a specific implementation, but many servers +will attempt to user hard links when moving files using SSH_FXP_RENAME. + +If the server does not support posix-rename@openssh.com, this function will +return LIBSSH2_FX_OP_UNSUPPORTED and you can call libssh2_sftp_rename_ex (3) as +a backup. +.SH RETURN VALUE +Return 0 on success or negative on failure. It returns +LIBSSH2_ERROR_EAGAIN when it would otherwise block. While +LIBSSH2_ERROR_EAGAIN is a negative number, it is not really a failure per se. +.SH ERRORS +\fILIBSSH2_FX_OP_UNSUPPORTED\fP - Server does not support +posix-rename@openssh.com + +\fILIBSSH2_ERROR_ALLOC\fP - An internal memory allocation call failed. + +\fILIBSSH2_ERROR_SOCKET_SEND\fP - Unable to send data on socket. + +\fILIBSSH2_ERROR_SOCKET_TIMEOUT\fP - + +\fILIBSSH2_ERROR_SFTP_PROTOCOL\fP - An invalid SFTP protocol response was +received on the socket, or an SFTP operation caused an errorcode to +be returned by the server. +.SH SEE ALSO +.BR libssh2_sftp_init(3) diff --git a/include/libssh2_sftp.h b/include/libssh2_sftp.h index b6551d74..ab7b0af4 100644 --- a/include/libssh2_sftp.h +++ b/include/libssh2_sftp.h @@ -303,6 +303,15 @@ LIBSSH2_API int libssh2_sftp_rename_ex(LIBSSH2_SFTP *sftp, LIBSSH2_SFTP_RENAME_ATOMIC | \ LIBSSH2_SFTP_RENAME_NATIVE) +LIBSSH2_API int libssh2_sftp_posix_rename_ex(LIBSSH2_SFTP *sftp, + const char *source_filename, + size_t srouce_filename_len, + const char *dest_filename, + size_t dest_filename_len); +#define libssh2_sftp_posix_rename(sftp, sourcefile, destfile) \ + libssh2_sftp_posix_rename_ex((sftp), (sourcefile), strlen(sourcefile), \ + (destfile), strlen(destfile)) + LIBSSH2_API int libssh2_sftp_unlink_ex(LIBSSH2_SFTP *sftp, const char *filename, unsigned int filename_len); diff --git a/src/sftp.c b/src/sftp.c index f8f1323e..4c5f414a 100644 --- a/src/sftp.c +++ b/src/sftp.c @@ -47,6 +47,7 @@ #include "sftp.h" #include +#include /* strtol() */ /* This release of libssh2 implements Version 5 with automatic downgrade * based on server's declaration @@ -988,20 +989,42 @@ static LIBSSH2_SFTP *sftp_init(LIBSSH2_SESSION *session) sftp_handle->version)); while(buf.dataptr < endp) { unsigned char *extname, *extdata; + size_t extname_len, extdata_len; + uint32_t extversion = 0; - if(_libssh2_get_string(&buf, &extname, NULL)) { + if(_libssh2_get_string(&buf, &extname, &extname_len)) { LIBSSH2_FREE(session, data); _libssh2_error(session, LIBSSH2_ERROR_BUFFER_TOO_SMALL, "Data too short when extracting extname"); goto sftp_init_error; } - if(_libssh2_get_string(&buf, &extdata, NULL)) { + if(_libssh2_get_string(&buf, &extdata, &extdata_len)) { LIBSSH2_FREE(session, data); _libssh2_error(session, LIBSSH2_ERROR_BUFFER_TOO_SMALL, "Data too short when extracting extdata"); goto sftp_init_error; } + + if(extdata_len > 0) { + char *extversion_str; + extversion_str = (char *)LIBSSH2_ALLOC(session, extdata_len + 1); + if(!extversion_str) { + _libssh2_error(session, LIBSSH2_ERROR_ALLOC, + "Unable to allocate memory for SSH_FXP_VERSION " + "packet"); + goto sftp_init_error; + } + memcpy(extversion_str, extdata, extdata_len); + extversion_str[extdata_len] = '\0'; + extversion = (uint32_t)strtol(extversion_str, NULL, 10); + LIBSSH2_FREE(session, extversion_str); + } + if(extname_len == 24 + && strncmp("posix-rename@openssh.com", (char *)extname, 24) == 0) { + sftp_handle->posix_rename_version = extversion; + } + } LIBSSH2_FREE(session, data); @@ -3015,6 +3038,136 @@ libssh2_sftp_rename_ex(LIBSSH2_SFTP *sftp, const char *source_filename, return rc; } +static int +sftp_posix_rename(LIBSSH2_SFTP *sftp, const char *source_filename, + size_t source_filename_len, + const char *dest_filename, + size_t dest_filename_len) +{ + LIBSSH2_CHANNEL *channel = sftp->channel; + LIBSSH2_SESSION *session = channel->session; + uint32_t packet_len; + size_t data_len = 0; + unsigned char *packet, *s, *data = NULL; + ssize_t rc; + uint32_t retcode; + + if(sftp->posix_rename_version != 1) { + return _libssh2_error(session, LIBSSH2_FX_OP_UNSUPPORTED, + "Server does not support" + "posix-rename@openssh.com"); + } + + if(source_filename_len > UINT32_MAX || + dest_filename_len > UINT32_MAX || + 45 + source_filename_len + dest_filename_len > UINT32_MAX) { + return _libssh2_error(session, LIBSSH2_ERROR_OUT_OF_BOUNDARY, + "Input too large" + "posix-rename@openssh.com"); + } + + packet_len = (uint32_t)(45 + source_filename_len + dest_filename_len); + + /* 45 = packet_len(4) + packet_type(1) + request_id(4) + + string_len(4) + strlen("posix-rename@openssh.com")(24) + + oldpath_len(4) + source_filename_len + + newpath_len(4) + dest_filename_len */ + + if(sftp->posix_rename_state == libssh2_NB_state_idle) { + _libssh2_debug((session, LIBSSH2_TRACE_SFTP, + "Issuing posix_rename command")); + s = packet = LIBSSH2_ALLOC(session, packet_len); + if(!packet) { + return _libssh2_error(session, LIBSSH2_ERROR_ALLOC, + "Unable to allocate memory for FXP_EXTENDED " + "packet"); + } + + _libssh2_store_u32(&s, packet_len - 4); + *(s++) = SSH_FXP_EXTENDED; + sftp->posix_rename_request_id = sftp->request_id++; + _libssh2_store_u32(&s, sftp->posix_rename_request_id); + _libssh2_store_str(&s, "posix-rename@openssh.com", 24); + _libssh2_store_str(&s, source_filename, source_filename_len); + _libssh2_store_str(&s, dest_filename, dest_filename_len); + + sftp->posix_rename_state = libssh2_NB_state_created; + } + else { + packet = sftp->posix_rename_packet; + } + + if(sftp->posix_rename_state == libssh2_NB_state_created) { + rc = _libssh2_channel_write(channel, 0, packet, packet_len); + if(rc == LIBSSH2_ERROR_EAGAIN || + (0 <= rc && rc < (ssize_t)packet_len)) { + sftp->posix_rename_packet = packet; + return LIBSSH2_ERROR_EAGAIN; + } + + LIBSSH2_FREE(session, packet); + sftp->posix_rename_packet = NULL; + + if(rc < 0) { + sftp->posix_rename_state = libssh2_NB_state_idle; + return _libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND, + "_libssh2_channel_write() failed"); + } + sftp->posix_rename_state = libssh2_NB_state_sent; + } + + rc = sftp_packet_require(sftp, SSH_FXP_STATUS, + sftp->posix_rename_request_id, + &data, &data_len, 9); + if(rc == LIBSSH2_ERROR_EAGAIN) { + return (int)rc; + } + else if(rc == LIBSSH2_ERROR_BUFFER_TOO_SMALL) { + if(data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP posix_rename packet too short"); + } + else if(rc) { + sftp->posix_rename_state = libssh2_NB_state_idle; + return (int)_libssh2_error(session, (int)rc, + "Error waiting for FXP EXTENDED REPLY"); + } + + sftp->posix_rename_state = libssh2_NB_state_idle; + + retcode = _libssh2_ntohu32(data + 5); + LIBSSH2_FREE(session, data); + + if(retcode != LIBSSH2_FX_OK) { + sftp->last_errno = retcode; + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "posix_rename failed"); + } + + return 0; +} + +/* libssh2_sftp_posix_rename_ex + * Rename a file on the remote server using the posix-rename@openssh.com + * extension. + */ +LIBSSH2_API int +libssh2_sftp_posix_rename_ex(LIBSSH2_SFTP *sftp, const char *source_filename, + size_t source_filename_len, + const char *dest_filename, + size_t dest_filename_len) +{ + int rc; + if(!sftp) + return LIBSSH2_ERROR_BAD_USE; + BLOCK_ADJUST(rc, sftp->channel->session, + sftp_posix_rename(sftp, source_filename, source_filename_len, + dest_filename, dest_filename_len)); + return rc; +} + /* sftp_fstatvfs * Get file system statistics */ diff --git a/src/sftp.h b/src/sftp.h index 267c8fef..f2baeff3 100644 --- a/src/sftp.h +++ b/src/sftp.h @@ -137,7 +137,7 @@ struct _LIBSSH2_SFTP { LIBSSH2_CHANNEL *channel; - uint32_t request_id, version; + uint32_t request_id, version, posix_rename_version; struct list_head packets; @@ -202,6 +202,11 @@ struct _LIBSSH2_SFTP unsigned char *rename_s; uint32_t rename_request_id; + /* State variables used in libssh2_sftp_posix_rename_ex() */ + libssh2_nonblocking_states posix_rename_state; + unsigned char *posix_rename_packet; + uint32_t posix_rename_request_id; + /* State variables used in libssh2_sftp_fstatvfs() */ libssh2_nonblocking_states fstatvfs_state; unsigned char *fstatvfs_packet;