cmdline.c

/*
 * cmdline.c - command-line parsing shared between many of the
 * PuTTY applications
 */

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include "putty.h"

/*
 * Some command-line parameters need to be saved up until after
 * we've loaded the saved session which will form the basis of our
 * eventual running configuration. For this we use the macro
 * SAVEABLE, which notices if the `need_save' parameter is set and
 * saves the parameter and value on a list.
 *
 * We also assign priorities to saved parameters, just to slightly
 * ameliorate silly ordering problems. For example, if you specify
 * a saved session to load, it will be loaded _before_ all your
 * local modifications such as -L are evaluated; and if you specify
 * a protocol and a port, the protocol is set up first so that the
 * port can override its choice of port number.
 *
 * (In fact -load is not saved at all, since in at least Plink the
 * processing of further command-line options depends on whether or
 * not the loaded session contained a hostname. So it must be
 * executed immediately.)
 */

#define NPRIORITIES 2

struct cmdline_saved_param {
  char *p, *value;
};
struct cmdline_saved_param_set {
  struct cmdline_saved_param *params;
  int nsaved, savesize;
};

/*
 * C guarantees this structure will be initialised to all zero at
 * program start, which is exactly what we want.
 */
static struct cmdline_saved_param_set saves[NPRIORITIES];

static void cmdline_save_param(const char *p, const char *value, int pri)
{
  if (saves[pri].nsaved >= saves[pri].savesize) {
    saves[pri].savesize = saves[pri].nsaved + 32;
    saves[pri].params = sresize(
        saves[pri].params, saves[pri].savesize, struct cmdline_saved_param);
  }
  saves[pri].params[saves[pri].nsaved].p = dupstr(p);
  saves[pri].params[saves[pri].nsaved].value = dupstr(value);
  saves[pri].nsaved++;
}

static char *cmdline_password = NULL;

void cmdline_cleanup(void)
{
  int pri;

  if (cmdline_password) {
    smemclr(cmdline_password, strlen(cmdline_password));
    sfree(cmdline_password);
    cmdline_password = NULL;
  }

  for (pri = 0; pri < NPRIORITIES; pri++) {
    sfree(saves[pri].params);
    saves[pri].params = NULL;
    saves[pri].savesize = 0;
    saves[pri].nsaved = 0;
  }
}

#define SAVEABLE(pri)                                                          \
  do {                                                                         \
    if (need_save) {                                                           \
      cmdline_save_param(p, value, pri);                                       \
      return ret;                                                              \
    }                                                                          \
  } while (0)

/*
 * Similar interface to get_userpass_input(), except that here a -1
 * return means that we aren't capable of processing the prompt and
 * someone else should do it.
 */
int cmdline_get_passwd_input(prompts_t *p, const unsigned char *in, int inlen)
{
  static int tried_once = 0;

  /*
   * We only handle prompts which don't echo (which we assume to be
   * passwords), and (currently) we only cope with a password prompt
   * that comes in a prompt-set on its own.
   */
  if (!cmdline_password || in || p->n_prompts != 1 || p->prompts[0]->echo) {
    return -1;
  }

  /*
   * If we've tried once, return utter failure (no more passwords left
   * to try).
   */
  if (tried_once)
    return 0;

  prompt_set_result(p->prompts[0], cmdline_password);
  smemclr(cmdline_password, strlen(cmdline_password));
  sfree(cmdline_password);
  cmdline_password = NULL;
  tried_once = 1;
  return 1;
}

/*
 * Here we have a flags word which describes the capabilities of
 * the particular tool on whose behalf we're running. We will
 * refuse certain command-line options if a particular tool
 * inherently can't do anything sensible. For example, the file
 * transfer tools (psftp, pscp) can't do a great deal with protocol
 * selections (ever tried running scp over telnet?) or with port
 * forwarding (even if it wasn't a hideously bad idea, they don't
 * have the select() infrastructure to make them work).
 */
int cmdline_tooltype = 0;

static int cmdline_check_unavailable(int flag, const char *p)
{
  if (cmdline_tooltype & flag) {
    cmdline_error("option \"%s\" not available in this tool", p);
    return 1;
  }
  return 0;
}

#define UNAVAILABLE_IN(flag)                                                   \
  do {                                                                         \
    if (cmdline_check_unavailable(flag, p))                                    \
      return ret;                                                              \
  } while (0)

/*
 * Process a standard command-line parameter. `p' is the parameter
 * in question; `value' is the subsequent element of argv, which
 * may or may not be required as an operand to the parameter.
 * If `need_save' is 1, arguments which need to be saved as
 * described at this top of this file are, for later execution;
 * if 0, they are processed normally. (-1 is a special value used
 * by pterm to count arguments for a preliminary pass through the
 * argument list; it causes immediate return with an appropriate
 * value with no action taken.)
 * Return value is 2 if both arguments were used; 1 if only p was
 * used; 0 if the parameter wasn't one we recognised; -2 if it
 * should have been 2 but value was NULL.
 */

#define RETURN(x)                                                              \
  do {                                                                         \
    if ((x) == 2 && !value)                                                    \
      return -2;                                                               \
    ret = x;                                                                   \
    if (need_save < 0)                                                         \
      return x;                                                                \
  } while (0)

int cmdline_process_param(const char *p, char *value, int need_save, Conf *conf)
{
  int ret = 0;

  if (!strcmp(p, "-load")) {
    RETURN(2);
    /* This parameter must be processed immediately rather than being
     * saved. */
    do_defaults(value, conf);
    loaded_session = TRUE;
    cmdline_session_name = dupstr(value);
    return 2;
  }
  if (!strcmp(p, "-ssh")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    default_protocol = PROT_SSH;
    default_port = 22;
    conf_set_int(conf, CONF_protocol, default_protocol);
    conf_set_int(conf, CONF_port, default_port);
    return 1;
  }
  if (!strcmp(p, "-telnet")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    default_protocol = PROT_TELNET;
    default_port = 23;
    conf_set_int(conf, CONF_protocol, default_protocol);
    conf_set_int(conf, CONF_port, default_port);
    return 1;
  }
  if (!strcmp(p, "-rlogin")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    default_protocol = PROT_RLOGIN;
    default_port = 513;
    conf_set_int(conf, CONF_protocol, default_protocol);
    conf_set_int(conf, CONF_port, default_port);
    return 1;
  }
  if (!strcmp(p, "-raw")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    default_protocol = PROT_RAW;
    conf_set_int(conf, CONF_protocol, default_protocol);
  }
  if (!strcmp(p, "-serial")) {
    RETURN(1);
    /* Serial is not NONNETWORK in an odd sense of the word */
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    default_protocol = PROT_SERIAL;
    conf_set_int(conf, CONF_protocol, default_protocol);
    /* The host parameter will already be loaded into CONF_host,
     * so copy it across */
    conf_set_str(conf, CONF_serline, conf_get_str(conf, CONF_host));
  }
  if (!strcmp(p, "-v")) {
    RETURN(1);
    flags |= FLAG_VERBOSE;
  }
  if (!strcmp(p, "-l")) {
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_str(conf, CONF_username, value);
  }
  if (!strcmp(p, "-loghost")) {
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_str(conf, CONF_loghost, value);
  }
  if (!strcmp(p, "-hostkey")) {
    char *dup;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    dup = dupstr(value);
    if (!validate_manual_hostkey(dup)) {
      cmdline_error("'%s' is not a valid format for a manual host "
                    "key specification",
                    value);
      sfree(dup);
      return ret;
    }
    conf_set_str_str(conf, CONF_ssh_manual_hostkeys, dup, "");
    sfree(dup);
  }
  if ((!strcmp(p, "-L") || !strcmp(p, "-R") || !strcmp(p, "-D"))) {
    char type, *q, *qq, *key, *val;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    if (strcmp(p, "-D")) {
      /*
       * For -L or -R forwarding types:
       *
       * We expect _at least_ two colons in this string. The
       * possible formats are `sourceport:desthost:destport',
       * or `sourceip:sourceport:desthost:destport' if you're
       * specifying a particular loopback address. We need to
       * replace the one between source and dest with a \t;
       * this means we must find the second-to-last colon in
       * the string.
       *
       * (This looks like a foolish way of doing it given the
       * existence of strrchr, but it's more efficient than
       * two strrchrs - not to mention that the second strrchr
       * would require us to modify the input string!)
       */

      type = p[1]; /* 'L' or 'R' */

      q = qq = host_strchr(value, ':');
      while (qq) {
        char *qqq = host_strchr(qq + 1, ':');
        if (qqq)
          q = qq;
        qq = qqq;
      }

      if (!q) {
        cmdline_error("-%c expects at least two colons in its"
                      " argument",
                      type);
        return ret;
      }

      key = dupprintf("%c%.*s", type, (int)(q - value), value);
      val = dupstr(q + 1);
    } else {
      /*
       * Dynamic port forwardings are entered under the same key
       * as if they were local (because they occupy the same
       * port space - a local and a dynamic forwarding on the
       * same local port are mutually exclusive), with the
       * special value "D" (which can be distinguished from
       * anything in the ordinary -L case by containing no
       * colon).
       */
      key = dupprintf("L%s", value);
      val = dupstr("D");
    }
    conf_set_str_str(conf, CONF_portfwd, key, val);
    sfree(key);
    sfree(val);
  }
  if ((!strcmp(p, "-nc"))) {
    char *host, *portp;

    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);

    portp = host_strchr(value, ':');
    if (!portp) {
      cmdline_error("-nc expects argument of form 'host:port'");
      return ret;
    }

    host = dupprintf("%.*s", (int)(portp - value), value);
    conf_set_str(conf, CONF_ssh_nc_host, host);
    conf_set_int(conf, CONF_ssh_nc_port, atoi(portp + 1));
    sfree(host);
  }
  if (!strcmp(p, "-m")) {
    const char *filename;
    char *command;
    int cmdlen, cmdsize;
    FILE *fp;
    int c, d;

    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);

    filename = value;

    cmdlen = cmdsize = 0;
    command = NULL;
    fp = fopen(filename, "r");
    if (!fp) {
      cmdline_error("unable to open command file \"%s\"", filename);
      return ret;
    }
    do {
      c = fgetc(fp);
      d = c;
      if (c == EOF)
        d = 0;
      if (cmdlen >= cmdsize) {
        cmdsize = cmdlen + 512;
        command = sresize(command, cmdsize, char);
      }
      command[cmdlen++] = d;
    } while (c != EOF);
    fclose(fp);
    conf_set_str(conf, CONF_remote_cmd, command);
    conf_set_str(conf, CONF_remote_cmd2, "");
    conf_set_int(conf, CONF_nopty, TRUE); /* command => no terminal */
    sfree(command);
  }
  if (!strcmp(p, "-P")) {
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(1); /* lower priority than -ssh,-telnet */
    conf_set_int(conf, CONF_port, atoi(value));
  }
  if (!strcmp(p, "-pw")) {
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(1);
    /* We delay evaluating this until after the protocol is decided,
     * so that we can warn if it's of no use with the selected protocol */
    if (conf_get_int(conf, CONF_protocol) != PROT_SSH)
      cmdline_error("the -pw option can only be used with the "
                    "SSH protocol");
    else {
      cmdline_password = dupstr(value);
      /* Assuming that `value' is directly from argv, make a good faith
       * attempt to trample it, to stop it showing up in `ps' output
       * on Unix-like systems. Not guaranteed, of course. */
      smemclr(value, strlen(value));
    }
  }

  if (!strcmp(p, "-agent") || !strcmp(p, "-pagent") || !strcmp(p, "-pageant")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_tryagent, TRUE);
  }
  if (!strcmp(p, "-noagent") || !strcmp(p, "-nopagent") ||
      !strcmp(p, "-nopageant")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_tryagent, FALSE);
  }

  if (!strcmp(p, "-A")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_agentfwd, 1);
  }
  if (!strcmp(p, "-a")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_agentfwd, 0);
  }

  if (!strcmp(p, "-X")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_x11_forward, 1);
  }
  if (!strcmp(p, "-x")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_x11_forward, 0);
  }

  if (!strcmp(p, "-t")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(1); /* lower priority than -m */
    conf_set_int(conf, CONF_nopty, 0);
  }
  if (!strcmp(p, "-T")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(1);
    conf_set_int(conf, CONF_nopty, 1);
  }

  if (!strcmp(p, "-N")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_ssh_no_shell, 1);
  }

  if (!strcmp(p, "-C")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_compression, 1);
  }

  if (!strcmp(p, "-1")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_sshprot, 0); /* ssh protocol 1 only */
  }
  if (!strcmp(p, "-2")) {
    RETURN(1);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_sshprot, 3); /* ssh protocol 2 only */
  }

  if (!strcmp(p, "-i")) {
    Filename *fn;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    fn = filename_from_str(value);
    conf_set_filename(conf, CONF_keyfile, fn);
    filename_free(fn);
  }

  if (!strcmp(p, "-4") || !strcmp(p, "-ipv4")) {
    RETURN(1);
    SAVEABLE(1);
    conf_set_int(conf, CONF_addressfamily, ADDRTYPE_IPV4);
  }
  if (!strcmp(p, "-6") || !strcmp(p, "-ipv6")) {
    RETURN(1);
    SAVEABLE(1);
    conf_set_int(conf, CONF_addressfamily, ADDRTYPE_IPV6);
  }
  if (!strcmp(p, "-sercfg")) {
    char *nextitem;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER | TOOLTYPE_NONNETWORK);
    SAVEABLE(1);
    if (conf_get_int(conf, CONF_protocol) != PROT_SERIAL)
      cmdline_error("the -sercfg option can only be used with the "
                    "serial protocol");
    /* Value[0] contains one or more , separated values, like 19200,8,n,1,X */
    nextitem = value;
    while (nextitem[0] != '\0') {
      int length, skip;
      char *end = strchr(nextitem, ',');
      if (!end) {
        length = strlen(nextitem);
        skip = 0;
      } else {
        length = end - nextitem;
        nextitem[length] = '\0';
        skip = 1;
      }
      if (length == 1) {
        switch (*nextitem) {
        case '1':
        case '2':
          conf_set_int(conf, CONF_serstopbits, 2 * (*nextitem - '0'));
          break;

        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
          conf_set_int(conf, CONF_serdatabits, *nextitem - '0');
          break;

        case 'n':
          conf_set_int(conf, CONF_serparity, SER_PAR_NONE);
          break;
        case 'o':
          conf_set_int(conf, CONF_serparity, SER_PAR_ODD);
          break;
        case 'e':
          conf_set_int(conf, CONF_serparity, SER_PAR_EVEN);
          break;
        case 'm':
          conf_set_int(conf, CONF_serparity, SER_PAR_MARK);
          break;
        case 's':
          conf_set_int(conf, CONF_serparity, SER_PAR_SPACE);
          break;

        case 'N':
          conf_set_int(conf, CONF_serflow, SER_FLOW_NONE);
          break;
        case 'X':
          conf_set_int(conf, CONF_serflow, SER_FLOW_XONXOFF);
          break;
        case 'R':
          conf_set_int(conf, CONF_serflow, SER_FLOW_RTSCTS);
          break;
        case 'D':
          conf_set_int(conf, CONF_serflow, SER_FLOW_DSRDTR);
          break;

        default:
          cmdline_error("Unrecognised suboption \"-sercfg %c\"", *nextitem);
        }
      } else if (length == 3 && !strncmp(nextitem, "1.5", 3)) {
        /* Messy special case */
        conf_set_int(conf, CONF_serstopbits, 3);
      } else {
        int serspeed = atoi(nextitem);
        if (serspeed != 0) {
          conf_set_int(conf, CONF_serspeed, serspeed);
        } else {
          cmdline_error("Unrecognised suboption \"-sercfg %s\"", nextitem);
        }
      }
      nextitem += length + skip;
    }
  }

  if (!strcmp(p, "-sessionlog")) {
    Filename *fn;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_FILETRANSFER);
    /* but available even in TOOLTYPE_NONNETWORK, cf pterm "-log" */
    SAVEABLE(0);
    fn = filename_from_str(value);
    conf_set_filename(conf, CONF_logfilename, fn);
    conf_set_int(conf, CONF_logtype, LGTYP_DEBUG);
    filename_free(fn);
  }

  if (!strcmp(p, "-sshlog") || !strcmp(p, "-sshrawlog")) {
    Filename *fn;
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    fn = filename_from_str(value);
    conf_set_filename(conf, CONF_logfilename, fn);
    conf_set_int(
        conf,
        CONF_logtype,
        !strcmp(p, "-sshlog") ? LGTYP_PACKETS :
                              /* !strcmp(p, "-sshrawlog") ? */ LGTYP_SSHRAW);
    filename_free(fn);
  }

  if (!strcmp(p, "-proxycmd")) {
    RETURN(2);
    UNAVAILABLE_IN(TOOLTYPE_NONNETWORK);
    SAVEABLE(0);
    conf_set_int(conf, CONF_proxy_type, PROXY_CMD);
    conf_set_str(conf, CONF_proxy_telnet_command, value);
  }

#ifdef _WINDOWS
  /*
   * Cross-tool options only available on Windows.
   */
  if (!strcmp(p, "-restrict-acl") || !strcmp(p, "-restrict_acl") ||
      !strcmp(p, "-restrictacl")) {
    RETURN(1);
    restrict_process_acl();
    restricted_acl = TRUE;
  }
#endif

  return ret; /* unrecognised */
}

void cmdline_run_saved(Conf *conf)
{
  int pri, i;
  for (pri = 0; pri < NPRIORITIES; pri++) {
    for (i = 0; i < saves[pri].nsaved; i++) {
      cmdline_process_param(
          saves[pri].params[i].p, saves[pri].params[i].value, 0, conf);
      sfree(saves[pri].params[i].p);
      sfree(saves[pri].params[i].value);
    }
    saves[pri].nsaved = 0;
  }
}