From 8daa83a594a2e98f39d764422bfbdbc62c9efd44 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 19:20:00 +0200 Subject: Adding upstream version 2:4.20.0+dfsg. Signed-off-by: Daniel Baumann --- source3/utils/smbfilter.c | 356 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 356 insertions(+) create mode 100644 source3/utils/smbfilter.c (limited to 'source3/utils/smbfilter.c') diff --git a/source3/utils/smbfilter.c b/source3/utils/smbfilter.c new file mode 100644 index 0000000..ebf2809 --- /dev/null +++ b/source3/utils/smbfilter.c @@ -0,0 +1,356 @@ +/* + Unix SMB/CIFS implementation. + SMB filter/socket plugin + Copyright (C) Andrew Tridgell 1999 + + 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 3 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, see . +*/ + +#include "includes.h" +#include "system/filesys.h" +#include "system/select.h" +#include "libsmb/namequery.h" +#include "../lib/util/select.h" +#include "libsmb/nmblib.h" +#include "lib/util/sys_rw_data.h" + +#define SECURITY_MASK 0 +#define SECURITY_SET 0 + +/* this forces non-unicode */ +#define CAPABILITY_MASK 0 +#define CAPABILITY_SET 0 + +/* and non-unicode for the client too */ +#define CLI_CAPABILITY_MASK 0 +#define CLI_CAPABILITY_SET 0 + +static char *netbiosname; + +static void save_file(const char *fname, void *ppacket, size_t length) +{ + int fd; + fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0644); + if (fd == -1) { + perror(fname); + return; + } + if (write(fd, ppacket, length) != length) { + fprintf(stderr,"Failed to write %s\n", fname); + close(fd); + return; + } + close(fd); + printf("Wrote %ld bytes to %s\n", (unsigned long)length, fname); +} + +static void filter_reply(char *buf) +{ + int msg_type = CVAL(buf,0); + int type = CVAL(buf,smb_com); + unsigned x; + + if (msg_type) return; + + switch (type) { + + case SMBnegprot: + /* force the security bits */ + x = CVAL(buf, smb_vwv1); + x = (x | SECURITY_SET) & ~SECURITY_MASK; + SCVAL(buf, smb_vwv1, x); + + /* force the capabilities */ + x = IVAL(buf,smb_vwv9+1); + x = (x | CAPABILITY_SET) & ~CAPABILITY_MASK; + SIVAL(buf, smb_vwv9+1, x); + break; + + } +} + +static void filter_request(char *buf, size_t buf_len) +{ + int msg_type = CVAL(buf,0); + int type = CVAL(buf,smb_com); + unsigned x; + fstring name1,name2; + int name_len1 = 0; + int name_len2; + int name_type1, name_type2; + int ret; + + if (msg_type) { + /* it's a netbios special */ + switch (msg_type) + case 0x81: + /* session request */ + /* inbuf_size is guaranteed to be at least 4. */ + name_len1 = name_len((unsigned char *)(buf+4), + buf_len - 4); + if (name_len1 <= 0 || name_len1 > buf_len - 4) { + DEBUG(0,("Invalid name length in session request\n")); + return; + } + name_len2 = name_len((unsigned char *)(buf+4+name_len1), + buf_len - 4 - name_len1); + if (name_len2 <= 0 || name_len2 > buf_len - 4 - name_len1) { + DEBUG(0,("Invalid name length in session request\n")); + return; + } + + name_type1 = name_extract((unsigned char *)buf, + buf_len,(unsigned int)4,name1); + name_type2 = name_extract((unsigned char *)buf, + buf_len,(unsigned int)(4 + name_len1),name2); + + if (name_type1 == -1 || name_type2 == -1) { + DEBUG(0,("Invalid name type in session request\n")); + return; + } + + d_printf("session_request: %s -> %s\n", + name1, name2); + if (netbiosname) { + char *mangled = name_mangle( + talloc_tos(), netbiosname, 0x20); + if (mangled != NULL) { + /* replace the destination netbios + * name */ + memcpy(buf+4, mangled, + name_len((unsigned char *)mangled, + talloc_get_size(mangled))); + TALLOC_FREE(mangled); + } + } + return; + } + + /* it's an ordinary SMB request */ + switch (type) { + case SMBsesssetupX: + /* force the client capabilities */ + x = IVAL(buf,smb_vwv11); + d_printf("SMBsesssetupX cap=0x%08x\n", x); + d_printf("pwlen=%d/%d\n", SVAL(buf, smb_vwv7), SVAL(buf, smb_vwv8)); + ret = system("mv sessionsetup.dat sessionsetup1.dat"); + if (ret == -1) { + DBG_ERR("failed to call mv command\n"); + } + save_file("sessionsetup.dat", smb_buf(buf), SVAL(buf, smb_vwv7)); + x = (x | CLI_CAPABILITY_SET) & ~CLI_CAPABILITY_MASK; + SIVAL(buf, smb_vwv11, x); + break; + } +} + +/**************************************************************************** + Send an smb to a fd. +****************************************************************************/ + +static bool send_smb(int fd, char *buffer) +{ + size_t len; + size_t nwritten=0; + ssize_t ret; + + len = smb_len(buffer) + 4; + + while (nwritten < len) { + ret = write_data(fd,buffer+nwritten,len - nwritten); + if (ret <= 0) { + DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n", + (int)len,(int)ret, strerror(errno) )); + return false; + } + nwritten += ret; + } + + return true; +} + +static void filter_child(int c, struct sockaddr_storage *dest_ss) +{ + NTSTATUS status; + int s = -1; + char packet[128*1024]; + + /* we have a connection from a new client, now connect to the server */ + status = open_socket_out(dest_ss, TCP_SMB_PORT, LONG_CONNECT_TIMEOUT, &s); + if (!NT_STATUS_IS_OK(status)) { + char addr[INET6_ADDRSTRLEN]; + if (dest_ss) { + print_sockaddr(addr, sizeof(addr), dest_ss); + } + + d_printf("Unable to connect to %s (%s)\n", + dest_ss?addr:"NULL", nt_errstr(status)); + exit(1); + } + + while (c != -1 || s != -1) { + struct pollfd fds[2]; + int num_fds, ret; + + memset(fds, 0, sizeof(struct pollfd) * 2); + fds[0].fd = -1; + fds[1].fd = -1; + num_fds = 0; + + if (s != -1) { + fds[num_fds].fd = s; + fds[num_fds].events = POLLIN|POLLHUP; + num_fds += 1; + } + if (c != -1) { + fds[num_fds].fd = c; + fds[num_fds].events = POLLIN|POLLHUP; + num_fds += 1; + } + + ret = sys_poll_intr(fds, num_fds, -1); + if (ret <= 0) { + continue; + } + + /* + * find c in fds and see if it's readable + */ + if ((c != -1) && + (((fds[0].fd == c) + && (fds[0].revents & (POLLIN|POLLHUP|POLLERR))) || + ((fds[1].fd == c) + && (fds[1].revents & (POLLIN|POLLHUP|POLLERR))))) { + size_t len; + if (!NT_STATUS_IS_OK(receive_smb_raw( + c, packet, sizeof(packet), + 0, 0, &len))) { + d_printf("client closed connection\n"); + exit(0); + } + filter_request(packet, len); + if (!send_smb(s, packet)) { + d_printf("server is dead\n"); + exit(1); + } + } + + /* + * find s in fds and see if it's readable + */ + if ((s != -1) && + (((fds[0].fd == s) + && (fds[0].revents & (POLLIN|POLLHUP|POLLERR))) || + ((fds[1].fd == s) + && (fds[1].revents & (POLLIN|POLLHUP|POLLERR))))) { + size_t len; + if (!NT_STATUS_IS_OK(receive_smb_raw( + s, packet, sizeof(packet), + 0, 0, &len))) { + d_printf("server closed connection\n"); + exit(0); + } + filter_reply(packet); + if (!send_smb(c, packet)) { + d_printf("client is dead\n"); + exit(1); + } + } + } + d_printf("Connection closed\n"); + exit(0); +} + + +static void start_filter(char *desthost) +{ + int s, c; + struct sockaddr_storage dest_ss; + struct sockaddr_storage my_ss; + + CatchChild(); + + /* start listening on port 445 locally */ + + zero_sockaddr(&my_ss); + s = open_socket_in(SOCK_STREAM, &my_ss, TCP_SMB_PORT, true); + + if (s < 0) { + d_printf("bind failed: %s\n", strerror(-s)); + exit(1); + } + + if (listen(s, 5) == -1) { + d_printf("listen failed\n"); + } + + if (!resolve_name(desthost, &dest_ss, 0x20, false)) { + d_printf("Unable to resolve host %s\n", desthost); + exit(1); + } + + while (1) { + int num, revents; + struct sockaddr_storage ss; + socklen_t in_addrlen = sizeof(ss); + + num = poll_intr_one_fd(s, POLLIN|POLLHUP, -1, &revents); + if ((num > 0) && (revents & (POLLIN|POLLHUP|POLLERR))) { + c = accept(s, (struct sockaddr *)&ss, &in_addrlen); + if (c != -1) { + smb_set_close_on_exec(c); + if (fork() == 0) { + close(s); + filter_child(c, &dest_ss); + exit(0); + } else { + close(c); + } + } + } + } +} + + +int main(int argc, char *argv[]) +{ + char *desthost; + const char *configfile; + TALLOC_CTX *frame = talloc_stackframe(); + + smb_init_locale(); + + setup_logging(argv[0], DEBUG_STDOUT); + + configfile = get_dyn_CONFIGFILE(); + + if (argc < 2) { + fprintf(stderr,"smbfilter \n"); + exit(1); + } + + desthost = argv[1]; + if (argc > 2) { + netbiosname = argv[2]; + } + + if (!lp_load_global(configfile)) { + d_printf("Unable to load config file\n"); + } + + start_filter(desthost); + gfree_all(); + TALLOC_FREE(frame); + return 0; +} -- cgit v1.2.3