Attachment 17996 Details for Bug 15431 – fake smb server that causes smbclient -L to crash

fake smb server that causes smbclient -L to crash

smc25b.c (text/x-csrc), 14.10 KB, created by Robert Morris on 2023-07-24 11:00:08 UTC

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Filename:

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Creator: Robert Morris

Created: 2023-07-24 11:00:08 UTC

Size: 14.10 KB

patch

obsolete

>#include <stdio.h>
>#include <string.h>
>#include <stdlib.h>
>#include <unistd.h>
>#include <sys/socket.h>
>#include <sys/time.h>
>#include <sys/types.h>
>#include <sys/ioctl.h>
>#include <netinet/in.h>
>#include <sys/wait.h>
>#include <sys/resource.h>
>#include <arpa/inet.h>
>#include <assert.h>
>#include <ctype.h>
>#include <fcntl.h>
>#include <signal.h>
>
>unsigned char session_id[8];
>
>int s = -1;
>
>int
>readn(void *bufx, int n)
>{
>  char *buf = bufx;
>  while(n > 0){
>    int cc = read(s, buf, n);
>    if(cc <= 0)
>      return -1;
>    n -= cc;
>    buf += cc;
>  }
>  return 0;
>}
>
>int
>readmsg(void *bufx)
>{
>  unsigned char *buf = bufx;
>  if(readn(buf, 4) < 0)
>    return -1;
>  int n = (buf[2] << 8) | buf[3];
>  if(readn(buf+4, n) < 0)
>    return -1;
>  return n + 4;
>}
>
>int
>header(char *buf, int command)
>{
>  int ii = 0;
>
>  unsigned int status = 0;
>  unsigned int flags = 1; // 1=REDIRECT
>
>  // SMB-over-TCP 4-byte header
>  buf[ii++] = 0; // must be zero
>  buf[ii++] = 0; // high byte of len
>  *(short*)(buf+ii) = htons(sizeof(buf)-4); // non-inclusive len, filled later
>  ii += 2;
>  
>  // SMB2 SYNC Packet Header, MS-SMB2 2.2.1.2
>  buf[ii++] = 0xfe;
>  buf[ii++] = 'S';
>  buf[ii++] = 'M';
>  buf[ii++] = 'B';
>  *(short*)(buf+ii) = 64; // StructureSize (of SMB2 header)
>  ii += 2;
>  *(short*)(buf+ii) = 0; // CreditCharge
>  ii += 2;
>  *(int*)(buf+ii) = status; // Status
>  ii += 4;
>  *(short*)(buf+ii) = command;
>  ii += 2;
>  *(short*)(buf+ii) = 6; // CreditRequest
>  ii += 2;
>  *(int*)(buf+ii) = flags; // Flags 
>  ii += 4;
>  *(int*)(buf+ii) = 0; // NextCommand
>  ii += 4;
>  static unsigned long long seq = 0;
>  *(long long *)(buf+ii) = seq++; // MessageId
>  ii += 8;
>  *(int*)(buf+ii) = 0; // Reserved
>  ii += 4;
>  *(int*)(buf+ii) = 0; // TreeId
>  ii += 4;
>  memcpy(buf+ii, session_id, 8); // SessionId
>  ii += 8;
>  memset(buf+ii, 'd', 16); // Signature
>  ii += 16;
>  
>  return ii;
>}
>
>void
>negotiate()
>{
>  // SMB2 NEGOTIATE, MS-SMB2 2.2.3
>  char buf[128+64];
>  memset(buf, 1, sizeof(buf));
>
>  int ii = header(buf, 0x0000);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 65; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = 0; // SecurityMode
>  ii += 2;
>  *(short*)(buf+ii) = 0x0311; // DialectRevision
>  ii += 2;
>  *(short*)(buf+ii) = 1; // NegotiateContextCount
>  ii += 2;
>  ii += 16; // ServerGuid from MS-DTYP
>  *(int*)(buf+ii) = 0x3e; // Capabilities
>  ii += 4;
>  *(int*)(buf+ii) = 8192; // MaxTransactSize
>  ii += 4;
>  *(int*)(buf+ii) = 8192; // MaxReadSize
>  ii += 4;
>  *(int*)(buf+ii) = 8192; // MaxWriteSize
>  ii += 4;
>  *(long long *)(buf+ii) = 1; // SystemTime
>  ii += 8;
>  *(long long *)(buf+ii) = 1; // ServerStartTime
>  ii += 8;
>  *(short*)(buf+ii) = 0; // SecurityBufferOffset
>  ii += 2;
>  *(short*)(buf+ii) = 0; // SecurityBufferLength
>  ii += 2;
>  int context_offset_i = ii;
>  *(int*)(buf+ii) = 0; // NegotiateContextOffset
>  ii += 4;
>
>  // SecurityBuffer
>
>  while((ii - 4) % 8)
>    ii++;
>
>  // NegotiateContextList
>  *(int*)(buf+context_offset_i) = ii - 4; // NegotiateContextOffset
>  
>  {
>    *(short*)(buf+ii) = 0x0001; // SMB2_PREAUTH_INTEGRITY_CAPABILITIES
>    ii += 2;
>    int data_length_i = ii;
>    *(short*)(buf+ii) = 0; // DataLength
>    ii += 2;
>    *(int*)(buf+ii) = 0; // Reserved
>    ii += 4;
>    int data_field_i = ii;
>    *(short*)(buf+ii) = 1; // HashAlgorithmCount
>    ii += 2;
>    *(short*)(buf+ii) = 2; // SaltLength
>    ii += 2;
>    *(short*)(buf+ii) = 1; // SHA-512
>    ii += 2;
>    *(short*)(buf+ii) = 1; // Salt
>    ii += 2;
>    *(short*)(buf+data_length_i) = ii - data_field_i;
>  }
>  
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("negotiate writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>void
>setup()
>{
>  // SMB2 SESSION_SETUP, MS-SMB2 2.2.6
>  char buf[128+64];
>  memset(buf, 1, sizeof(buf));
>
>  session_id[7] = 1;
>
>  int ii = header(buf, 0x0001);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 9; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = 1; // SessionFlags, 1=guest
>  ii += 2;
>  *(short*)(buf+ii) = (ii - 4 + 4); // SecurityBufferOffset
>  ii += 2;
>  *(short*)(buf+ii) = 16; // SecurityBufferLength
>  ii += 2;
>
>  memcpy(buf+ii, "NTLMSSP", 8);
>  
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("setup writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>void
>tree_connect()
>{
>  // SMB2 TREE_CONNECT, MS-SMB2 2.2.10
>  char buf[128+64];
>  memset(buf, 1, sizeof(buf));
>
>  int ii = header(buf, 0x0003);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 16; // StructureSize
>  ii += 2;
>  buf[ii++] = 0x01; // ShareType, 1=disk, 2=pipe, 3=print
>  buf[ii++] = 0; // Reserved
>  *(int*)(buf+ii) = 0x33; // ShareFlags
>  ii += 4;
>  *(int*)(buf+ii) = 0x1f8; // Capabilities
>  ii += 4;
>  *(int*)(buf+ii) = 0xffffffff; // MaximalAccess
>  ii += 4;
>  
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("tree_connect writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>void
>smb_ioctl()
>{
>  // SMB2 IOCTL, MS-SMB2 2.2.32
>  char buf[128+64];
>  memset(buf, 1, sizeof(buf));
>
>  int ii = header(buf, 0x000b);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 49; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = 0; // Reserved
>  ii += 2;
>  *(int*)(buf+ii) = 0; // CtlCode
>  ii += 4;
>  ii += 16; // FileId
>  *(int*)(buf+ii) = 0; // InputOffset
>  ii += 4;
>  *(int*)(buf+ii) = 0; // InputCount
>  ii += 4;
>  *(int*)(buf+ii) = (ii-4+16); // OutputOffset
>  ii += 4;
>  *(int*)(buf+ii) = 4; // OutputCount
>  ii += 4;
>  *(int*)(buf+ii) = 0; // Flags
>  ii += 4;
>  *(int*)(buf+ii) = 0; // Reserved
>  ii += 4;
>
>  *(short*)(buf+ii) = 2; // consumed_ucs
>  ii += 2;
>  *(short*)(buf+ii) = 0; // num_referrals
>  ii += 2;
>  buf[ii++] = 0;
>  buf[ii++] = 'x';
>
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("ioctl writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>void
>smb_create()
>{
>  // SMB2 CREATE, MS-SMB2 2.2.14
>  char buf[128+64];
>  memset(buf, 0xff, sizeof(buf));
>
>  int ii = header(buf, 0x0005);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 89; // StructureSize
>  ii += 2;
>  buf[ii++] = 0; // OplockLevel
>  buf[ii++] = 0; // Flags
>  *(int*)(buf+ii) = 0; // CreateAction
>  ii += 4;
>  *(long long*)(buf+ii) = 1; // CreationTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastAccessTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastWriteTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // ChangeTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // AllocationSize
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // EndofFile
>  ii += 8;
>  // 0x10 directory
>  *(int*)(buf+ii) = 0x10; // FileAttributes
>  ii += 4;
>  *(int*)(buf+ii) = 0; // Reserved2
>  ii += 4;
>  ii += 16; // FileId
>  *(int*)(buf+ii) = (ii - 4 + 8); // CreateContextsOffset
>  ii += 4;
>  *(int*)(buf+ii) = 32; // CreateContextsLength
>  ii += 4;
>
>  // one context
>  *(int*)(buf+ii) = 0; // Next
>  ii += 4;
>  *(short*)(buf+ii) = 16; // NameOffset
>  ii += 2;
>  *(short*)(buf+ii) = 4; // NameLength
>  ii += 2;
>  *(short*)(buf+ii) = 0; // Reserved
>  ii += 2;
>  *(short*)(buf+ii) = 24; // DataOffset
>  ii += 2;
>  *(int*)(buf+ii) = 8; // DataLength
>  ii += 4;
>  
>
>  // SMB2_CREATE_QUERY_MAXIMAL_ACCESS_RESPONSE
>  *(int*)(buf+ii) = 0x4d784163; // Name
>  ii += 4;
>  ii += 4; // pad
>  *(int*)(buf+ii) = 0; // QueryStatus
>  ii += 4;
>  *(int*)(buf+ii) = 0xffffffff; // MaximalAccess
>  ii += 4;
>
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("create writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>void
>smb_close()
>{
>  char buf[128+64];
>  memset(buf, 0xff, sizeof(buf));
>
>  int ii = header(buf, 0x0006);
>  int ii0 = ii;
>  
>  *(short*)(buf+ii) = 60; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = 0; // Flags
>  ii += 2;
>  *(int*)(buf+ii) = 0; // Reserved
>  ii += 4;
>  *(long long*)(buf+ii) = 1; // CreationTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastAccessTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastWriteTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // ChangeTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // AllocationSize
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // EndofFile
>  ii += 8;
>  // 0x10 directory
>  *(int*)(buf+ii) = 0x10; // FileAttributes
>  ii += 4;
>
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("close writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>  
>void
>query_directory(int any)
>{
>  char buf[256+128];
>  memset(buf, 0xff, sizeof(buf));
>
>  int ii = header(buf, 0x000e);
>  int ii0 = ii;
>
>  if(any == 0){
>    *(int*)(buf+12) = 0x80000006; // STATUS_NO_MORE_FILES
>  }
>  
>  *(short*)(buf+ii) = 9; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = (ii - 4 + 6); // OutputBufferOffset
>  ii += 2;
>  *(int*)(buf+ii) = any ? 106 : 0; // OutputBufferLength
>  ii += 4;
>
>  // probably FileBothDirectoryInformation, MS-FSCC 2.4.8
>  *(int*)(buf+ii) = 0; // NextEntryOffset
>  ii += 4;
>  *(int*)(buf+ii) = 1; // FileIndex
>  ii += 4;
>  *(long long*)(buf+ii) = 1; // CreationTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastAccessTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastWriteTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // ChangeTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // EndofFile
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // AllocationSize
>  ii += 8;
>  // 0x10 directory
>  *(int*)(buf+ii) = 0x10; // FileAttributes
>  ii += 4;
>  *(int*)(buf+ii) = 2; // FileNameLength
>  ii += 4;
>  *(int*)(buf+ii) = 0; // EaSize
>  ii += 4;
>  buf[ii++] = 2; // ShortNameLength
>  buf[ii++] = 0; // Reserved
>  buf[ii++] = 'f'; // ShortName
>  buf[ii++] = 0;
>  ii += 22;
>  buf[ii++] = 'f'; // FileName
>  buf[ii++] = 0;
>
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("query_directory writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>  
>void
>query_info()
>{
>  char buf[256+128];
>  memset(buf, 0xff, sizeof(buf));
>
>  int ii = header(buf, 0x0010);
>  int ii0 = ii;
>
>  *(short*)(buf+ii) = 9; // StructureSize
>  ii += 2;
>  *(short*)(buf+ii) = (ii - 4 + 6); // OutputBufferOffset
>  ii += 2;
>  *(int*)(buf+ii) = 106; // OutputBufferLength
>  ii += 4;
>
>  // probably FileBothDirectoryInformation, MS-FSCC 2.4.8
>  *(int*)(buf+ii) = 0; // NextEntryOffset
>  ii += 4;
>  *(int*)(buf+ii) = 1; // FileIndex
>  ii += 4;
>  *(long long*)(buf+ii) = 1; // CreationTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastAccessTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // LastWriteTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // ChangeTime
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // EndofFile
>  ii += 8;
>  *(long long*)(buf+ii) = 1; // AllocationSize
>  ii += 8;
>  // 0x10 directory
>  *(int*)(buf+ii) = 0x10; // FileAttributes
>  ii += 4;
>  *(int*)(buf+ii) = 2; // FileNameLength
>  ii += 4;
>  *(int*)(buf+ii) = 0; // EaSize
>  ii += 4;
>  buf[ii++] = 2; // ShortNameLength
>  buf[ii++] = 0; // Reserved
>  buf[ii++] = 'f'; // ShortName
>  buf[ii++] = 0;
>  ii += 22;
>  buf[ii++] = 'f'; // FileName
>  buf[ii++] = 0;
>
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("query_info writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>  
>void
>smb_read()
>{
>  char buf[256];
>  memset(buf, 0, sizeof(buf));
>
>  int ii = header(buf, 0x0008);
>  int ii0 = ii;
>
>  *(short*)(buf+ii) = 17; // StructureSize
>  ii += 2;
>  buf[ii] = 0; // DataOffset
>  ii++;
>  buf[ii++] = 0; // Reserved
>  *(int*)(buf+ii) = 2; // DataLength
>  ii += 4;
>  *(int*)(buf+ii) = 0; // DataRemaining
>  ii += 4;
>  *(int*)(buf+ii) = 0; // Flags
>  ii += 4;
>  
>  assert(ii <= sizeof(buf));
>  
>  ii = sizeof(buf);
>  
>  *(short*)(buf+2) = htons(ii-4); // non-inclusive len
>  
>  printf("read writing %d bytes\n", ii); fflush(stdout);
>  
>  if(write(s, buf, ii) <= 0){
>    perror("write");
>  }
>}
>
>char *command_names[] = {
>  "NEGOTIATE",
>  "SESSION_SETUP",
>  "LOGOFF",
>  "TREE_CONNECT",
>  "TREE_DISCONNECT",
>  "CREATE",
>  "CLOSE",
>  "FLUSH",
>  "READ",
>  "WRITE",
>  "LOCK",
>  "IOCTL",
>  "CANCEL",
>  "ECHO",
>  "QUERY_DIRECTORY",
>  "CHANGE_NOTIFY",
>  "QUERY_INFO",
>  "SET_INFO",
>  "OPLOCK_BREAK",
>  "0x0012",
>};
>
>int
>main()
>{
>  signal(SIGPIPE, SIG_IGN);
>
>  struct sockaddr_in sin;
>  memset(&sin, 0, sizeof(sin));
>  sin.sin_family = AF_INET;
>  sin.sin_port = htons(445); // SMB over TCP
>
>  int ss = socket(AF_INET, SOCK_STREAM, 0);
>  int yes = 1;
>  setsockopt(ss, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
>  if(bind(ss, (struct sockaddr *)&sin, sizeof(sin)) < 0){
>    perror("bind");
>    exit(1);
>  }
>  listen(ss, 10);
>
>  printf("waiting for a connection on port 445\n");
>
>  socklen_t sinlen = sizeof(sin);
>  s = accept(ss, (struct sockaddr *)&sin, &sinlen);
>  if(s < 0){
>    perror("accept");
>    exit(1);
>  }
>  close(ss);
>
>  sleep(1);
>
>  unsigned int command;
>  int n;
>  char ibuf[2048];
>
>  memset(ibuf, 0, sizeof(ibuf));
>  n = readmsg(ibuf);
>  command = *(short*)(ibuf+16);
>  printf("read %d, command %d %s\n", n, command, command_names[command]);
>  negotiate();
>
>  memset(ibuf, 0, sizeof(ibuf));
>  n = readmsg(ibuf);
>  command = *(short*)(ibuf+16);
>  printf("read %d, command %d %s\n", n, command, command_names[command]);
>  if(command == 1){
>    setup();
>  }
>
>  memset(ibuf, 0, sizeof(ibuf));
>  n = readmsg(ibuf);
>  command = *(short*)(ibuf+16);
>  printf("read %d, command %d %s\n", n, command, command_names[command]);
>  if(command == 3){
>    tree_connect();
>  }
>
>  while(1){
>    memset(ibuf, 0, sizeof(ibuf));
>    n = readmsg(ibuf);
>    if(n < 0)
>      break;
>    command = *(short*)(ibuf+16);
>    printf("command 0x%02x %s\n", command, command_names[command]);
>    if(command == 0xb){
>      smb_ioctl();
>    } else if(command == 5){
>      smb_create();
>    } else if(command == 6){
>      smb_close();
>    } else if(command == 0xe){
>      static int nn = 0;
>      query_directory(nn == 0 ? 1 : 0);
>      nn++;
>    } else if(command == 0x10){
>      query_info();
>    } else if(command == 0x08){
>      smb_read();
>      break;
>    } else {
>      break;
>    }
>  }
>  
>  sleep(1);
>  close(s);
>}

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Attachments on bug 15431: 17996