/* * options.c - handle pre-connection options * * This file is part of the SSH Library * * Copyright (c) 2003-2008 by Aris Adamantiadis * Copyright (c) 2009 by Andreas Schneider * * The SSH Library is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or (at your * option) any later version. * * The SSH Library 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 Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with the SSH Library; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ #include "config.h" #include #include #include #ifndef _WIN32 #include #else #include #endif #include #include "libssh/priv.h" #include "libssh/session.h" #include "libssh/misc.h" #ifdef WITH_SERVER #include "libssh/server.h" #endif /** * @brief Duplicate the options of a session structure. * * If you make several sessions with the same options this is useful. You * cannot use twice the same option structure in ssh_session_connect. * * @param opt Option structure to copy. * * @returns New copied option structure, NULL on error. * * @see ssh_session_connect() */ int ssh_options_copy(ssh_session src, ssh_session *dest) { ssh_session new; int i; if (src == NULL || dest == NULL || *dest == NULL) { return -1; } new = *dest; if (src->username) { new->username = strdup(src->username); if (new->username == NULL) { return -1; } } if (src->host) { new->host = strdup(src->host); if (new->host == NULL) { return -1; } } if (src->identity) { new->identity = strdup(src->identity); if (new->identity == NULL) { return -1; } } if (src->sshdir) { new->sshdir = strdup(src->sshdir); if (new->sshdir == NULL) { return -1; } } if (src->knownhosts) { new->knownhosts = strdup(src->knownhosts); if (new->knownhosts == NULL) { return -1; } } for (i = 0; i < 10; ++i) { if (src->wanted_methods[i]) { new->wanted_methods[i] = strdup(src->wanted_methods[i]); if (new->wanted_methods[i] == NULL) { return -1; } } } new->fd = src->fd; new->port = src->port; new->callbacks = src->callbacks; new->timeout = src->timeout; new->timeout_usec = src->timeout_usec; new->ssh2 = src->ssh2; new->ssh1 = src->ssh1; new->log_verbosity = src->log_verbosity; return 0; } #ifndef _WIN32 static char *get_username_from_uid(ssh_session session, uid_t uid){ struct passwd *pwd = NULL; char *name; pwd = getpwuid(uid); if (pwd == NULL) { ssh_set_error(session, SSH_FATAL, "uid %d doesn't exist !", uid); return NULL; } name = strdup(pwd->pw_name); if (name == NULL) { ssh_set_error_oom(session); return NULL; } return name; } #endif int ssh_options_set_algo(ssh_session session, int algo, const char *list) { if (!verify_existing_algo(algo, list)) { ssh_set_error(session, SSH_REQUEST_DENIED, "Setting method: no algorithm for method \"%s\" (%s)\n", ssh_kex_nums[algo], list); return -1; } SAFE_FREE(session->wanted_methods[algo]); session->wanted_methods[algo] = strdup(list); if (session->wanted_methods[algo] == NULL) { ssh_set_error_oom(session); return -1; } return 0; } char *dir_expand_dup(ssh_session session, const char *value, int allowsshdir) { char *new; if (value[0] == '~' && value[1] == '/') { char *homedir = ssh_get_user_home_dir(); size_t lv, lh; if (homedir == NULL) { return NULL; } lv = strlen(value + 1); lh = strlen(homedir); new = malloc(lv + lh + 1); if (new == NULL) { ssh_set_error_oom(session); SAFE_FREE(homedir); return NULL; } memcpy(new, homedir, lh); SAFE_FREE(homedir); memcpy(new + lh, value + 1, lv + 1); return new; } if (allowsshdir && strncmp(value, "SSH_DIR/", 8) == 0) { size_t lv, ls; if (session->sshdir == NULL) { if (ssh_options_set(session, SSH_OPTIONS_SSH_DIR, NULL) < 0) return NULL; } value += 7; lv = strlen(value); ls = strlen(session->sshdir); new = malloc(lv + ls + 1); if (new == NULL) { ssh_set_error_oom(session); return NULL; } memcpy(new, session->sshdir, ls); memcpy(new + ls, value, lv + 1); return new; } new = strdup(value); if (new == NULL) { ssh_set_error_oom(session); return NULL; } return new; } /** * @brief This function can set all possible ssh options. * * @param session An allocated ssh option structure. * * @param type The option type to set. This could be one of the * following: * * SSH_OPTIONS_HOST: * The hostname or ip address to connect to (string). * * SSH_OPTIONS_PORT: * The port to connect to (integer). * * SSH_OPTIONS_PORT_STR: * The port to connect to (string). * * SSH_OPTIONS_FD: * The file descriptor to use (socket_t). * * If you wish to open the socket yourself for a reason * or another, set the file descriptor. Don't forget to * set the hostname as the hostname is used as a key in * the known_host mechanism. * * SSH_OPTIONS_USER: * The username for authentication (string). * * If the value is NULL, the username is set to the * default username. * * SSH_OPTIONS_SSH_DIR: * Set the ssh directory (format string). * * If the value is NULL, the directory is set to the * default ssh directory. * * The ssh directory is used for files like known_hosts * and identity (private and public key). It may include * "%s" which will be replaced by the user home * directory. * * SSH_OPTIONS_KNOWNHOSTS: * Set the known hosts file name (format string). * * If the value is NULL, the directory is set to the * default known hosts file, normally ~/.ssh/known_hosts. * * The known hosts file is used to certify remote hosts * are genuine. It may include "%s" which will be * replaced by the user home directory. * * SSH_OPTIONS_IDENTITY: * Set the identity file name (format string). * * By default identity, id_dsa and id_rsa are checked. * * The identity file used authenticate with public key. * It may include "%s" which will be replaced by the * user home directory. * * SSH_OPTIONS_TIMEOUT: * Set a timeout for the connection in seconds (integer). * * SSH_OPTIONS_TIMEOUT_USEC: * Set a timeout for the connection in micro seconds * (integer). * * SSH_OPTIONS_SSH1: * Allow or deny the connection to SSH1 servers * (integer). * * SSH_OPTIONS_SSH2: * Allow or deny the connection to SSH2 servers * (integer). * * SSH_OPTIONS_LOG_VERBOSITY: * Set the session logging verbosity (integer). * * The verbosity of the messages. Every log smaller or * equal to verbosity will be shown. * SSH_LOG_NOLOG: No logging * SSH_LOG_RARE: Rare conditions or warnings * SSH_LOG_ENTRY: API-accessible entrypoints * SSH_LOG_PACKET: Packet id and size * SSH_LOG_FUNCTIONS: Function entering and leaving * * SSH_OPTTIONS_AUTH_CALLBACK: * Set a callback to use your own authentication function * (function pointer). * * SSH_OPTTIONS_AUTH_USERDATA: * Set the user data passed to the authentication function * (generic pointer). * * SSH_OPTTIONS_LOG_CALLBACK: * Set a callback to use your own logging function * (function pointer). * * SSH_OPTTIONS_LOG_USERDATA: * Set the user data passed to the logging function * (generic pointer). * * SSH_OPTTIONS_STATUS_CALLBACK: * Set a callback to show connection status in realtime * (function pointer). * * fn(void *arg, float status) * * During ssh_connect(), libssh will call the callback * with status from 0.0 to 1.0. * * SSH_OPTTIONS_STATUS_ARG: * Set the status argument which should be passed to the * status callback (generic pointer). * * SSH_OPTIONS_CIPHERS_C_S: * Set the symmetric cipher client to server (string, * comma-separated list). * * SSH_OPTIONS_CIPHERS_S_C: * Set the symmetric cipher server to client (string, * comma-separated list). * * SSH_OPTIONS_COMPRESSION_C_S: * Set the compression to use for client to server * communication (string, "none" or "zlib"). * * SSH_OPTIONS_COMPRESSION_S_C: * Set the compression to use for server to client * communication (string, "none" or "zlib"). * * @param value The value to set. This is a generic pointer and the * datatype which is used should be set according to the * type set. * * @return 0 on success, < 0 on error. */ int ssh_options_set(ssh_session session, enum ssh_options_e type, const void *value) { char *p, *q; long int i; if (session == NULL) { return -1; } switch (type) { case SSH_OPTIONS_HOST: q = strdup(value); if (q == NULL) { ssh_set_error_oom(session); return -1; } p = strchr(q, '@'); SAFE_FREE(session->host); if (p) { *p = '\0'; session->host = strdup(p + 1); if (session->host == NULL) { SAFE_FREE(q); ssh_set_error_oom(session); return -1; } SAFE_FREE(session->username); session->username = strdup(q); SAFE_FREE(q); if (session->username == NULL) { ssh_set_error_oom(session); return -1; } } else { session->host = q; } break; case SSH_OPTIONS_PORT: if (value == NULL) { session->port = 22 & 0xffff; } else { int *x = (int *) value; session->port = *x & 0xffff; } break; case SSH_OPTIONS_PORT_STR: if (value == NULL) { session->port = 22 & 0xffff; } else { q = strdup(value); if (q == NULL) { ssh_set_error_oom(session); return -1; } i = strtol(q, &p, 10); if (q == p) { SAFE_FREE(q); } SAFE_FREE(q); session->port = i & 0xffff; } break; case SSH_OPTIONS_USER: SAFE_FREE(session->username); if (value == NULL) { /* set default username */ #ifdef _WIN32 DWORD size = 0; GetUserName(NULL, &size); //Get Size q = malloc(size); if (q == NULL) { ssh_set_error_oom(session); return -1; } if (GetUserName(q, &size)) { session->username = q; } else { SAFE_FREE(q); return -1; } #else /* _WIN32 */ q = get_username_from_uid(session, getuid()); if (q == NULL) { return -1; } session->username = q; #endif /* _WIN32 */ } else { /* username provided */ session->username = strdup(value); if (session->username == NULL) { ssh_set_error_oom(session); return -1; } } break; case SSH_OPTIONS_SSH_DIR: if (value == NULL) { SAFE_FREE(session->sshdir); /* TODO: why ~/.ssh/ instead of ~/.ssh ? */ session->sshdir = dir_expand_dup(session, "~/.ssh/", 0); if (session->sshdir == NULL) { return -1; } } else { SAFE_FREE(session->sshdir); session->sshdir = dir_expand_dup(session, value, 0); if (session->sshdir == NULL) { return -1; } } break; case SSH_OPTIONS_IDENTITY: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } SAFE_FREE(session->identity); session->identity = dir_expand_dup(session, value, 1); if (session->identity == NULL) { return -1; } break; case SSH_OPTIONS_KNOWNHOSTS: if (value == NULL) { SAFE_FREE(session->knownhosts); session->knownhosts = dir_expand_dup(session, "SSH_DIR/known_hosts", 1); if (session->knownhosts == NULL) { return -1; } } else { SAFE_FREE(session->knownhosts); session->knownhosts = dir_expand_dup(session, value, 1); if (session->knownhosts == NULL) { return -1; } } break; case SSH_OPTIONS_TIMEOUT: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { long *x = (long *) value; session->timeout = *x; } break; case SSH_OPTIONS_TIMEOUT_USEC: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { long *x = (long *) value; session->timeout_usec = *x; } break; case SSH_OPTIONS_SSH1: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { int *x = (int *) value; session->ssh1 = *x; } break; case SSH_OPTIONS_SSH2: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { int *x = (int *) value; session->ssh2 = *x; } break; case SSH_OPTIONS_LOG_VERBOSITY: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { int *x = (int *) value; session->log_verbosity = *x; } case SSH_OPTIONS_CIPHERS_C_S: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { if (ssh_options_set_algo(session, SSH_CRYPT_C_S, value) < 0) return -1; } break; case SSH_OPTIONS_CIPHERS_S_C: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { if (ssh_options_set_algo(session, SSH_CRYPT_S_C, value) < 0) return -1; } break; case SSH_OPTIONS_COMPRESSION_C_S: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { if (ssh_options_set_algo(session, SSH_COMP_C_S, value) < 0) return -1; } break; case SSH_OPTIONS_COMPRESSION_S_C: if (value == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } else { if (ssh_options_set_algo(session, SSH_COMP_S_C, value) < 0) return -1; } break; default: ssh_set_error(session, SSH_REQUEST_DENIED, "Unkown ssh option %d", type); return -1; break; } return 0; } #ifdef WITH_SERVER static int ssh_bind_options_set_algo(ssh_bind sshbind, int algo, const char *list) { if (!verify_existing_algo(algo, list)) { ssh_set_error(sshbind, SSH_REQUEST_DENIED, "Setting method: no algorithm for method \"%s\" (%s)\n", ssh_kex_nums[algo], list); return -1; } SAFE_FREE(sshbind->wanted_methods[algo]); sshbind->wanted_methods[algo] = strdup(list); if (sshbind->wanted_methods[algo] == NULL) { ssh_set_error_oom(sshbind); return -1; } return 0; } /** * @brief This function can set all possible ssh bind options. * * @param session An allocated ssh option structure. * * @param type The option type to set. This could be one of the * following: * * SSH_BIND_OPTIONS_LOG_VERBOSITY: * Set the session logging verbosity (integer). * * The verbosity of the messages. Every log smaller or * equal to verbosity will be shown. * SSH_LOG_NOLOG: No logging * SSH_LOG_RARE: Rare conditions or warnings * SSH_LOG_ENTRY: API-accessible entrypoints * SSH_LOG_PACKET: Packet id and size * SSH_LOG_FUNCTIONS: Function entering and leaving * * SSH_BIND_OPTIONS_LOG_VERBOSITY_STR: * Set the session logging verbosity (integer). * * The verbosity of the messages. Every log smaller or * equal to verbosity will be shown. * SSH_LOG_NOLOG: No logging * SSH_LOG_RARE: Rare conditions or warnings * SSH_LOG_ENTRY: API-accessible entrypoints * SSH_LOG_PACKET: Packet id and size * SSH_LOG_FUNCTIONS: Function entering and leaving * * SSH_BIND_OPTIONS_BINDADDR: * Set the bind address. * * SSH_BIND_OPTIONS_BINDPORT: * Set the bind port, default is 22. * * SSH_BIND_OPTIONS_HOSTKEY: * Set the server public key type: ssh-rsa or ssh-dss * (string). * * SSH_BIND_OPTIONS_DSAKEY: * Set the path to the dsa ssh host key (string). * * SSH_BIND_OPTIONS_RSAKEY: * Set the path to the ssh host rsa key (string). * * SSH_BIND_OPTIONS_BANNER: * Set the server banner sent to clients (string). * * @param value The value to set. This is a generic pointer and the * datatype which is used should be set according to the * type set. * * @return 0 on success, < 0 on error. */ int ssh_bind_options_set(ssh_bind sshbind, enum ssh_bind_options_e type, const void *value) { char *p, *q; int i; if (sshbind == NULL) { return -1; } switch (type) { case SSH_BIND_OPTIONS_HOSTKEY: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { if (ssh_bind_options_set_algo(sshbind, SSH_HOSTKEYS, value) < 0) return -1; } break; case SSH_BIND_OPTIONS_BINDADDR: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { SAFE_FREE(sshbind->bindaddr); sshbind->bindaddr = strdup(value); if (sshbind->bindaddr == NULL) { ssh_set_error_oom(sshbind); return -1; } } break; case SSH_BIND_OPTIONS_BINDPORT: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { int *x = (int *) value; sshbind->bindport = *x & 0xffff; } break; case SSH_BIND_OPTIONS_BINDPORT_STR: if (value == NULL) { sshbind->bindport = 22 & 0xffff; } else { q = strdup(value); if (q == NULL) { ssh_set_error_oom(sshbind); return -1; } i = strtol(q, &p, 10); if (q == p) { SAFE_FREE(q); } SAFE_FREE(q); sshbind->bindport = i & 0xffff; } break; case SSH_BIND_OPTIONS_LOG_VERBOSITY: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { int *x = (int *) value; sshbind->log_verbosity = *x & 0xffff; } break; case SSH_BIND_OPTIONS_LOG_VERBOSITY_STR: if (value == NULL) { sshbind->log_verbosity = 0; } else { q = strdup(value); if (q == NULL) { ssh_set_error_oom(sshbind); return -1; } i = strtol(q, &p, 10); if (q == p) { SAFE_FREE(q); } SAFE_FREE(q); sshbind->log_verbosity = i & 0xffff; } break; case SSH_BIND_OPTIONS_DSAKEY: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { SAFE_FREE(sshbind->dsakey); sshbind->dsakey = strdup(value); if (sshbind->dsakey == NULL) { ssh_set_error_oom(sshbind); return -1; } } break; case SSH_BIND_OPTIONS_RSAKEY: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { SAFE_FREE(sshbind->rsakey); sshbind->rsakey = strdup(value); if (sshbind->rsakey == NULL) { ssh_set_error_oom(sshbind); return -1; } } break; case SSH_BIND_OPTIONS_BANNER: if (value == NULL) { ssh_set_error_invalid(sshbind, __FUNCTION__); return -1; } else { SAFE_FREE(sshbind->banner); sshbind->banner = strdup(value); if (sshbind->banner == NULL) { ssh_set_error_oom(sshbind); return -1; } } break; default: ssh_set_error(sshbind, SSH_REQUEST_DENIED, "Unkown ssh option %d", type); return -1; break; } return 0; } #endif /** * @brief Parse command line arguments. * * This is a helper for your application to generate the appropriate * options from the command line arguments.\n * The argv array and argc value are changed so that the parsed * arguments wont appear anymore in them.\n * The single arguments (without switches) are not parsed. thus, * myssh -l user localhost\n * The command wont set the hostname value of options to localhost. * * @param session The session to configure. * * @param argcptr The pointer to the argument count. * * @param argv The arguments list pointer. * * @returns 0 on success, < 0 on error. * * @see ssh_session_new() */ int ssh_options_getopt(ssh_session session, int *argcptr, char **argv) { char *user = NULL; char *cipher = NULL; char *localaddr = NULL; char *identity = NULL; char *port = NULL; char *bindport = NULL; char **save = NULL; int i = 0; int argc = *argcptr; int debuglevel = 0; int usersa = 0; int usedss = 0; int compress = 0; int cont = 1; int current = 0; #ifdef WITH_SSH1 int ssh1 = 1; #else int ssh1 = 0; #endif int ssh2 = 1; #ifdef _MSC_VER /* Not supported with a Microsoft compiler */ return -1; #else int saveoptind = optind; /* need to save 'em */ int saveopterr = opterr; save = malloc(argc * sizeof(char *)); if (save == NULL) { ssh_set_error_oom(session); return -1; } opterr = 0; /* shut up getopt */ while(cont && ((i = getopt(argc, argv, "c:i:Cl:p:vb:t:rd12")) != -1)) { switch(i) { case 'l': user = optarg; break; case 'p': port = optarg; break; case 't': bindport = optarg; break; case 'v': debuglevel++; break; case 'r': usersa++; break; case 'd': usedss++; break; case 'c': cipher = optarg; break; case 'i': identity = optarg; break; case 'b': localaddr = optarg; break; case 'C': compress++; break; case '2': ssh2 = 1; ssh1 = 0; break; case '1': ssh2 = 0; ssh1 = 1; break; default: { char opt[3]="- "; opt[1] = optopt; save[current] = strdup(opt); if (save[current] == NULL) { SAFE_FREE(save); ssh_set_error_oom(session); return -1; } current++; if (optarg) { save[current++] = argv[optind + 1]; } } } /* switch */ } /* while */ opterr = saveopterr; while (optind < argc) { save[current++] = argv[optind++]; } if (usersa && usedss) { ssh_set_error(session, SSH_FATAL, "Either RSA or DSS must be chosen"); cont = 0; } ssh_options_set(session, SSH_OPTIONS_LOG_VERBOSITY, &debuglevel); optind = saveoptind; if(!cont) { SAFE_FREE(save); return -1; } /* first recopy the save vector into the original's */ for (i = 0; i < current; i++) { /* don't erase argv[0] */ argv[ i + 1] = save[i]; } argv[current + 1] = NULL; *argcptr = current + 1; SAFE_FREE(save); /* set a new option struct */ if (compress) { if (ssh_options_set(session, SSH_OPTIONS_COMPRESSION_C_S, "zlib") < 0) { cont = 0; } if (ssh_options_set(session, SSH_OPTIONS_COMPRESSION_S_C, "zlib") < 0) { cont = 0; } } if (cont && cipher) { if (ssh_options_set(session, SSH_OPTIONS_CIPHERS_C_S, cipher) < 0) { cont = 0; } if (cont && ssh_options_set(session, SSH_OPTIONS_CIPHERS_S_C, cipher) < 0) { cont = 0; } } if (cont && user) { if (ssh_options_set(session, SSH_OPTIONS_USER, user) < 0) { cont = 0; } } if (cont && identity) { if (ssh_options_set(session, SSH_OPTIONS_IDENTITY, identity) < 0) { cont = 0; } } ssh_options_set(session, SSH_OPTIONS_PORT_STR, port); ssh_options_set(session, SSH_OPTIONS_SSH1, &ssh1); ssh_options_set(session, SSH_OPTIONS_SSH2, &ssh2); if (!cont) { return SSH_ERROR; } return SSH_OK; #endif } /** * @brief Parse the ssh config file. * * This should be the last call of all options, it may overwrite options which * are already set. It requires that the host name is already set with * ssh_options_set_host(). * * @param session SSH session handle * * @param filename The options file to use, if NULL the default * ~/.ssh/config will be used. * * @return 0 on success, < 0 on error. * * @see ssh_options_set_host() */ int ssh_options_parse_config(ssh_session session, const char *filename) { char *expanded_filename; int r; if (session == NULL) { return -1; } if (session->host == NULL) { ssh_set_error_invalid(session, __FUNCTION__); return -1; } /* set default filename */ if (filename == NULL) { expanded_filename = dir_expand_dup(session, "SSH_DIR/config", 1); } else { expanded_filename = dir_expand_dup(session, filename, 1); } if (expanded_filename == NULL) return -1; r = ssh_config_parse_file(session, expanded_filename); free(expanded_filename); return r; } /** @} */ /* vim: set ts=2 sw=2 et cindent: */