From 6c56c1e0d72670da274f3e77c51a7b4e078d59c6 Mon Sep 17 00:00:00 2001 From: Chris Townsend Date: Wed, 5 Sep 2018 10:51:38 -0500 Subject: [PATCH] sftpserver: Support some openssh extensions Add support for "hardlink@openssh.com" and "posix-rename@openssh.com" extensions. Signed-off-by: Chris Townsend Signed-off-by: Alberto Aguirre Reviewed-by: Andreas Schneider --- include/libssh/sftp.h | 3 +++ src/sftp.c | 9 ++++++++- src/sftpserver.c | 28 ++++++++++++++++++++++++++++ 3 files changed, 39 insertions(+), 1 deletion(-) diff --git a/include/libssh/sftp.h b/include/libssh/sftp.h index eeb4e615..b18bdc48 100644 --- a/include/libssh/sftp.h +++ b/include/libssh/sftp.h @@ -135,6 +135,7 @@ struct sftp_client_message_struct { ssh_string data; /* can be newpath of rename() */ ssh_buffer complete_message; /* complete message in case of retransmission*/ char *str_data; /* cstring version of data */ + char *submessage; /* for extended messages */ }; struct sftp_request_queue_struct { @@ -863,6 +864,7 @@ LIBSSH_API const char *sftp_client_message_get_filename(sftp_client_message msg) LIBSSH_API void sftp_client_message_set_filename(sftp_client_message msg, const char *newname); LIBSSH_API const char *sftp_client_message_get_data(sftp_client_message msg); LIBSSH_API uint32_t sftp_client_message_get_flags(sftp_client_message msg); +LIBSSH_API const char *sftp_client_message_get_submessage(sftp_client_message msg); LIBSSH_API int sftp_send_client_message(sftp_session sftp, sftp_client_message msg); LIBSSH_API int sftp_reply_name(sftp_client_message msg, const char *name, sftp_attributes attr); @@ -1012,6 +1014,7 @@ LIBSSH_API void sftp_handle_remove(sftp_session sftp, void *handle); #define SFTP_RENAME SSH_FXP_RENAME #define SFTP_READLINK SSH_FXP_READLINK #define SFTP_SYMLINK SSH_FXP_SYMLINK +#define SFTP_EXTENDED SSH_FXP_EXTENDED /* openssh flags */ #define SSH_FXE_STATVFS_ST_RDONLY 0x1 /* read-only */ diff --git a/src/sftp.c b/src/sftp.c index 6fc08f61..9a98d444 100644 --- a/src/sftp.c +++ b/src/sftp.c @@ -222,6 +222,7 @@ int sftp_server_init(sftp_session sftp){ sftp_packet packet = NULL; ssh_buffer reply = NULL; uint32_t version; + int rc; packet = sftp_packet_read(sftp); if (packet == NULL) { @@ -249,7 +250,13 @@ int sftp_server_init(sftp_session sftp){ return -1; } - if (ssh_buffer_add_u32(reply, ntohl(LIBSFTP_VERSION)) < 0) { + rc = ssh_buffer_pack(reply, "dssss", + LIBSFTP_VERSION, + "posix-rename@openssh.com", + "1", + "hardlink@openssh.com", + "1"); + if (rc != SSH_OK) { ssh_set_error_oom(session); ssh_buffer_free(reply); return -1; diff --git a/src/sftpserver.c b/src/sftpserver.c index 68fdb3d2..3cb30090 100644 --- a/src/sftpserver.c +++ b/src/sftpserver.c @@ -202,6 +202,29 @@ sftp_client_message sftp_get_client_message(sftp_session sftp) { return NULL; } break; + case SSH_FXP_EXTENDED: + rc = ssh_buffer_unpack(payload, + "s", + &msg->submessage); + if (rc != SSH_OK) { + ssh_set_error_oom(session); + sftp_client_message_free(msg); + return NULL; + } + + if (strcmp(msg->submessage, "hardlink@openssh.com") == 0 || + strcmp(msg->submessage, "posix-rename@openssh.com") == 0) { + rc = ssh_buffer_unpack(payload, + "sS", + &msg->filename, + &msg->data); + if (rc != SSH_OK) { + ssh_set_error_oom(session); + sftp_client_message_free(msg); + return NULL; + } + } + break; default: ssh_set_error(sftp->session, SSH_FATAL, "Received unhandled sftp message %d", msg->type); @@ -242,12 +265,17 @@ uint32_t sftp_client_message_get_flags(sftp_client_message msg){ return msg->flags; } +const char *sftp_client_message_get_submessage(sftp_client_message msg){ + return msg->submessage; +} + void sftp_client_message_free(sftp_client_message msg) { if (msg == NULL) { return; } SAFE_FREE(msg->filename); + SAFE_FREE(msg->submessage); ssh_string_free(msg->data); ssh_string_free(msg->handle); sftp_attributes_free(msg->attr);