/* Copyright (c) 2012-2013, Matthias Schiffer All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "fastd.h" #include "lex.h" #include "peer.h" #include #include #include #include #include #include #include #include #include extern const fastd_protocol_t fastd_protocol_ec25519_fhmqvc; extern const fastd_method_t fastd_method_null; #ifdef WITH_METHOD_XSALSA20_POLY1305 extern const fastd_method_t fastd_method_xsalsa20_poly1305; #endif #ifdef WITH_METHOD_AES128_GCM extern const fastd_method_t fastd_method_aes128_gcm; #endif #ifdef USE_CRYPTO_AES128CTR #ifdef WITH_CRYPTO_AES128CTR_NACL extern const fastd_crypto_aes128ctr_t fastd_crypto_aes128ctr_nacl; #endif #ifdef WITH_CRYPTO_AES128CTR_LINUX extern const fastd_crypto_aes128ctr_t fastd_crypto_aes128ctr_linux; #endif #ifdef WITH_CRYPTO_AES128CTR_NACL static const fastd_crypto_aes128ctr_t *fastd_crypto_aes128ctr_default = &fastd_crypto_aes128ctr_nacl; #else static const fastd_crypto_aes128ctr_t *fastd_crypto_aes128ctr_default = &fastd_crypto_aes128ctr_linux; #endif #endif #ifdef USE_CRYPTO_GHASH #ifdef WITH_CRYPTO_GHASH_BUILTIN extern const fastd_crypto_ghash_t fastd_crypto_ghash_builtin; #endif #ifdef WITH_CRYPTO_GHASH_LINUX extern const fastd_crypto_ghash_t fastd_crypto_ghash_linux; #endif #ifdef WITH_CRYPTO_GHASH_BUILTIN static const fastd_crypto_ghash_t *fastd_crypto_ghash_default = &fastd_crypto_ghash_builtin; #else static const fastd_crypto_ghash_t *fastd_crypto_ghash_default = &fastd_crypto_ghash_linux; #endif #endif static void default_config(fastd_config_t *conf) { memset(conf, 0, sizeof(fastd_config_t)); conf->log_syslog_ident = strdup("fastd"); conf->keepalive_interval = 10; conf->keepalive_timeout = 15; conf->peer_stale_time = 90; conf->eth_addr_stale_time = 300; conf->reorder_count = 64; conf->reorder_time = 10; conf->min_handshake_interval = 15; conf->min_resolve_interval = 15; conf->mtu = 1500; conf->mode = MODE_TAP; conf->drop_caps = DROP_CAPS_ON; conf->protocol = &fastd_protocol_ec25519_fhmqvc; conf->method_default = &fastd_method_null; conf->key_valid = 3600; /* 60 minutes */ conf->key_valid_old = 60; /* 1 minute */ conf->key_refresh = 3300; /* 55 minutes */ conf->key_refresh_splay = 300; /* 5 minutes */ #ifdef USE_CRYPTO_AES128CTR conf->crypto_aes128ctr = fastd_crypto_aes128ctr_default; #endif #ifdef USE_CRYPTO_GHASH conf->crypto_ghash = fastd_crypto_ghash_default; #endif conf->peer_group = calloc(1, sizeof(fastd_peer_group_config_t)); conf->peer_group->name = strdup("default"); conf->peer_group->max_connections = -1; } bool fastd_config_protocol(fastd_context_t *ctx UNUSED, fastd_config_t *conf, const char *name) { if (!strcmp(name, "ec25519-fhmqvc")) conf->protocol = &fastd_protocol_ec25519_fhmqvc; else return false; return true; } static inline const fastd_method_t* parse_method_name(const char *name) { if (!strcmp(name, "null")) return &fastd_method_null; #ifdef WITH_METHOD_XSALSA20_POLY1305 else if (!strcmp(name, "xsalsa20-poly1305")) return &fastd_method_xsalsa20_poly1305; #endif #ifdef WITH_METHOD_AES128_GCM else if (!strcmp(name, "aes128-gcm")) return &fastd_method_aes128_gcm; #endif else return NULL; } bool fastd_config_method(fastd_context_t *ctx, fastd_config_t *conf, const char *name) { const fastd_method_t *method = parse_method_name(name); if (!method) return false; conf->method_default = method; int i; for (i = 0; i < MAX_METHODS; i++) { if (conf->methods[i] == method) return true; if (conf->methods[i] == NULL) { conf->methods[i] = method; return true; } } exit_bug(ctx, "MAX_METHODS too low"); } bool fastd_config_crypto(fastd_context_t *ctx UNUSED, fastd_config_t *conf UNUSED, const char *alg UNUSED, const char *impl UNUSED) { #ifdef USE_CRYPTO_AES128CTR if (!strcasecmp(alg, "aes128-ctr") || !strcasecmp(alg, "aes128") || !strcasecmp(alg, "aes-ctr") || !strcasecmp(alg, "aes")) { if (!strcasecmp(impl, "default")) conf->crypto_aes128ctr = fastd_crypto_aes128ctr_default; #ifdef WITH_CRYPTO_AES128CTR_NACL else if (!strcasecmp(impl, "nacl")) conf->crypto_aes128ctr = &fastd_crypto_aes128ctr_nacl; #endif #ifdef WITH_CRYPTO_AES128CTR_LINUX else if (!strcasecmp(impl, "linux")) conf->crypto_aes128ctr = &fastd_crypto_aes128ctr_linux; #endif else return false; return true; } else #endif #ifdef USE_CRYPTO_GHASH if (!strcasecmp(alg, "ghash")) { if (!strcasecmp(impl, "default")) conf->crypto_ghash = fastd_crypto_ghash_default; #ifdef WITH_CRYPTO_GHASH_BUILTIN else if (!strcasecmp(impl, "builtin")) conf->crypto_ghash = &fastd_crypto_ghash_builtin; #endif #ifdef WITH_CRYPTO_GHASH_LINUX else if (!strcasecmp(impl, "linux")) conf->crypto_ghash = &fastd_crypto_ghash_linux; #endif else return false; return true; } else #endif return false; } bool fastd_config_bind_address(fastd_context_t *ctx UNUSED, fastd_config_t *conf, const fastd_peer_address_t *address, const char *bindtodev, bool default_v4, bool default_v6) { #ifndef USE_BINDTODEVICE if (bindtodev) return false; #endif #ifndef USE_MULTIAF_BIND if (address->sa.sa_family == AF_UNSPEC) { fastd_peer_address_t addr4 = { .in = { .sin_family = AF_INET, .sin_port = address->in.sin_port } }; fastd_peer_address_t addr6 = { .in6 = { .sin6_family = AF_INET6, .sin6_port = address->in.sin_port } }; if (!fastd_config_bind_address(ctx, conf, &addr4, bindtodev, default_v4, default_v6)) return false; if (!fastd_config_bind_address(ctx, conf, &addr6, bindtodev, default_v4, default_v6)) return false; return true; } #endif fastd_bind_address_t *addr = malloc(sizeof(fastd_bind_address_t)); addr->next = conf->bind_addrs; conf->bind_addrs = addr; conf->n_bind_addrs++; addr->addr = *address; addr->bindtodev = bindtodev ? strdup(bindtodev) : NULL; fastd_peer_address_simplify(&addr->addr); if (addr->addr.sa.sa_family != AF_INET6 && (default_v4 || !conf->bind_addr_default_v4)) conf->bind_addr_default_v4 = addr; if (addr->addr.sa.sa_family != AF_INET && (default_v6 || !conf->bind_addr_default_v6)) conf->bind_addr_default_v6 = addr; return true; } void fastd_config_peer_group_push(fastd_context_t *ctx UNUSED, fastd_config_t *conf, const char *name) { fastd_peer_group_config_t *group = calloc(1, sizeof(fastd_peer_group_config_t)); group->name = strdup(name); group->max_connections = -1; group->parent = conf->peer_group; group->next = group->parent->children; group->parent->children = group; conf->peer_group = group; } void fastd_config_peer_group_pop(fastd_context_t *ctx UNUSED, fastd_config_t *conf) { conf->peer_group = conf->peer_group->parent; } static void free_peer_group(fastd_peer_group_config_t *group) { while (group->children) { fastd_peer_group_config_t *next = group->children->next; free_peer_group(group->children); group->children = next; } fastd_string_stack_free(group->peer_dirs); free(group->name); free(group); } static bool has_peer_group_peer_dirs(const fastd_peer_group_config_t *group) { if (group->peer_dirs) return true; const fastd_peer_group_config_t *child; for (child = group->children; child; child = child->next) { if (has_peer_group_peer_dirs(child)) return true; } return false; } bool fastd_config_add_log_file(fastd_context_t *ctx, fastd_config_t *conf, const char *name, fastd_loglevel_t level) { char *name2 = strdup(name); char *name3 = strdup(name); char *dir = dirname(name2); char *base = basename(name3); char *oldcwd = get_current_dir_name(); if (!chdir(dir)) { char *logdir = get_current_dir_name(); fastd_log_file_t *file = malloc(sizeof(fastd_log_file_t)); file->filename = malloc(strlen(logdir) + 1 + strlen(base) + 1); strcpy(file->filename, logdir); strcat(file->filename, "/"); strcat(file->filename, base); file->level = level; file->next = conf->log_files; conf->log_files = file; if(chdir(oldcwd)) pr_error(ctx, "can't chdir to `%s': %s", oldcwd, strerror(errno)); free(logdir); } else { pr_error(ctx, "change from directory `%s' to `%s' failed: %s", oldcwd, dir, strerror(errno)); } free(oldcwd); free(name2); free(name3); return true; } static void read_peer_dir(fastd_context_t *ctx, fastd_config_t *conf, const char *dir) { DIR *dirh = opendir("."); if (dirh) { while (true) { errno = 0; struct dirent *result = readdir(dirh); if (!result) { if (errno) pr_error_errno(ctx, "readdir"); break; } if (result->d_name[0] == '.') continue; if (result->d_name[strlen(result->d_name)-1] == '~') { pr_verbose(ctx, "ignoring file `%s' as it seems to be a backup file", result->d_name); continue; } struct stat statbuf; if (stat(result->d_name, &statbuf)) { pr_warn(ctx, "ignoring file `%s': stat failed: %s", result->d_name, strerror(errno)); continue; } if ((statbuf.st_mode & S_IFMT) != S_IFREG) { pr_info(ctx, "ignoring file `%s': no regular file", result->d_name); continue; } fastd_peer_config_new(ctx, conf); conf->peers->name = strdup(result->d_name); conf->peers->config_source_dir = dir; if (!fastd_read_config(ctx, conf, result->d_name, true, 0)) { pr_warn(ctx, "peer config `%s' will be ignored", result->d_name); fastd_peer_config_delete(ctx, conf); } } if (closedir(dirh) < 0) pr_error_errno(ctx, "closedir"); } else { pr_error(ctx, "opendir for `%s' failed: %s", dir, strerror(errno)); } } static void read_peer_dirs(fastd_context_t *ctx, fastd_config_t *conf) { char *oldcwd = get_current_dir_name(); fastd_string_stack_t *dir; for (dir = conf->peer_group->peer_dirs; dir; dir = dir->next) { if (!chdir(dir->str)) read_peer_dir(ctx, conf, dir->str); else pr_error(ctx, "change from directory `%s' to `%s' failed: %s", oldcwd, dir->str, strerror(errno)); } if (chdir(oldcwd)) pr_error(ctx, "can't chdir to `%s': %s", oldcwd, strerror(errno)); free(oldcwd); } void fastd_add_peer_dir(fastd_context_t *ctx, fastd_config_t *conf, const char *dir) { char *oldcwd = get_current_dir_name(); if (!chdir(dir)) { char *newdir = get_current_dir_name(); conf->peer_group->peer_dirs = fastd_string_stack_push(conf->peer_group->peer_dirs, newdir); free(newdir); if(chdir(oldcwd)) pr_error(ctx, "can't chdir to `%s': %s", oldcwd, strerror(errno)); } else { pr_error(ctx, "change from directory `%s' to `%s' failed: %s", oldcwd, dir, strerror(errno)); } free(oldcwd); } bool fastd_read_config(fastd_context_t *ctx, fastd_config_t *conf, const char *filename, bool peer_config, int depth) { if (depth >= MAX_CONFIG_DEPTH) exit_error(ctx, "maximum config include depth exceeded"); bool ret = true; char *oldcwd = get_current_dir_name(); char *filename2 = NULL; char *dir = NULL; FILE *file; fastd_lex_t *lex = NULL; fastd_config_pstate *ps; fastd_string_stack_t *strings = NULL; ps = fastd_config_pstate_new(); if (!filename) { file = stdin; } else { file = fopen(filename, "r"); if (!file) { pr_error(ctx, "can't open config file `%s': %s", filename, strerror(errno)); ret = false; goto end_free; } } lex = fastd_lex_init(file); if (filename) { filename2 = strdup(filename); dir = dirname(filename2); if (chdir(dir)) { pr_error(ctx, "change from directory `%s' to `%s' failed", oldcwd, dir); ret = false; goto end_free; } } int token; YYSTYPE token_val; YYLTYPE loc = {1, 0, 1, 0}; if (peer_config) token = START_PEER_CONFIG; else token = conf->peer_group->parent ? START_PEER_GROUP_CONFIG : START_CONFIG; int parse_ret = fastd_config_push_parse(ps, token, &token_val, &loc, ctx, conf, filename, depth+1); while(parse_ret == YYPUSH_MORE) { token = fastd_lex(&token_val, &loc, lex); if (token < 0) { pr_error(ctx, "config error: %s at %s:%i:%i", token_val.error, filename, loc.first_line, loc.first_column); ret = false; goto end_free; } if (token == TOK_STRING) { token_val.str->next = strings; strings = token_val.str; } parse_ret = fastd_config_push_parse(ps, token, &token_val, &loc, ctx, conf, filename, depth+1); } if (parse_ret) ret = false; end_free: fastd_string_stack_free(strings); fastd_lex_destroy(lex); fastd_config_pstate_delete(ps); if(chdir(oldcwd)) pr_error(ctx, "can't chdir to `%s': %s", oldcwd, strerror(errno)); free(filename2); free(oldcwd); if (filename && file) fclose(file); return ret; } static void assess_peers(fastd_context_t *ctx, fastd_config_t *conf) { conf->has_floating = false; fastd_peer_config_t *peer; for (peer = conf->peers; peer; peer = peer->next) { if (fastd_peer_config_is_floating(peer)) conf->has_floating = true; if (peer->dynamic_float_deprecated) pr_warn(ctx, "peer `%s' uses deprecated float syntax, please update your configuration", peer->name); } } static void configure_user(fastd_context_t *ctx, fastd_config_t *conf) { conf->uid = getuid(); conf->gid = getgid(); if (conf->user) { struct passwd pwd, *pwdr; size_t bufspace = 1024; int error; do { char buf[bufspace]; error = getpwnam_r(conf->user, &pwd, buf, bufspace, &pwdr); bufspace *= 2; } while(error == ERANGE); if (error) exit_errno(ctx, "getpwnam_r"); if (!pwdr) exit_error(ctx, "Unable to find user `%s'.", conf->user); conf->uid = pwdr->pw_uid; conf->gid = pwdr->pw_gid; } if (conf->group) { struct group grp, *grpr; size_t bufspace = 1024; int error; do { char buf[bufspace]; error = getgrnam_r(conf->group, &grp, buf, bufspace, &grpr); bufspace *= 2; } while(error == ERANGE); if (error) exit_errno(ctx, "getgrnam_r"); if (!grpr) exit_error(ctx, "Unable to find group `%s'.", conf->group); conf->gid = grpr->gr_gid; } if (conf->user) { int ngroups = 0; if (getgrouplist(conf->user, conf->gid, NULL, &ngroups) < 0) { /* the user has supplementary groups */ conf->groups = calloc(ngroups, sizeof(gid_t)); if (getgrouplist(conf->user, conf->gid, conf->groups, &ngroups) < 0) exit_errno(ctx, "getgrouplist"); conf->n_groups = ngroups; } } } static void configure_method_parameters(fastd_context_t *ctx, fastd_config_t *conf) { conf->max_packet_size = 0; conf->min_encrypt_head_space = 0; conf->min_decrypt_head_space = 0; conf->min_encrypt_tail_space = 0; conf->min_decrypt_tail_space = 0; int i; for (i = 0; i < MAX_METHODS; i++) { if (!conf->methods[i]) break; conf->max_packet_size = max_size_t(conf->max_packet_size, conf->methods[i]->max_packet_size(ctx)); conf->min_encrypt_head_space = max_size_t(conf->min_encrypt_head_space, conf->methods[i]->min_encrypt_head_space(ctx)); conf->min_decrypt_head_space = max_size_t(conf->min_decrypt_head_space, conf->methods[i]->min_decrypt_head_space(ctx)); conf->min_encrypt_tail_space = max_size_t(conf->min_encrypt_tail_space, conf->methods[i]->min_encrypt_tail_space(ctx)); conf->min_decrypt_tail_space = max_size_t(conf->min_decrypt_tail_space, conf->methods[i]->min_decrypt_tail_space(ctx)); } conf->min_encrypt_head_space = alignto(conf->min_encrypt_head_space, 16); /* ugly hack to get alignment right for aes128-gcm, which needs data aligned to 16 and has a 24 byte header */ conf->min_decrypt_head_space = alignto(conf->min_decrypt_head_space, 16) + 8; } void fastd_configure(fastd_context_t *ctx, fastd_config_t *conf, int argc, char *const argv[]) { default_config(conf); fastd_config_handle_options(ctx, conf, argc, argv); if (!conf->log_stderr_level && !conf->log_syslog_level && !conf->log_files) conf->log_stderr_level = FASTD_DEFAULT_LOG_LEVEL; if (!conf->methods[0]) conf->methods[0] = conf->method_default; ctx->conf = conf; if (conf->generate_key || conf->show_key) return; if (conf->ifname) { if (strchr(conf->ifname, '/')) exit_error(ctx, "config error: invalid interface name"); } if (conf->mode == MODE_TUN) { if (!conf->peers || conf->peers->next) exit_error(ctx, "config error: in TUN mode exactly one peer must be configured"); if (conf->peer_group->children) exit_error(ctx, "config error: in TUN mode peer groups can't be used"); if (has_peer_group_peer_dirs(conf->peer_group)) exit_error(ctx, "config error: in TUN mode peer directories can't be used"); } if (!conf->peers && !has_peer_group_peer_dirs(conf->peer_group)) exit_error(ctx, "config error: neither fixed peers nor peer dirs have been configured"); #ifndef USE_PMTU if (conf->pmtu.set) exit_error(ctx, "config error: setting pmtu is not supported on this system"); #endif configure_user(ctx, conf); configure_method_parameters(ctx, conf); } static void peer_dirs_read_peer_group(fastd_context_t *ctx, fastd_config_t *new_conf) { read_peer_dirs(ctx, new_conf); fastd_peer_group_config_t *group; for (group = new_conf->peer_group->children; group; group = group->next) { new_conf->peer_group = group; peer_dirs_read_peer_group(ctx, new_conf); } } static void peer_dirs_handle_old_peers(fastd_context_t *ctx, fastd_peer_config_t **old_peers, fastd_peer_config_t **new_peers) { fastd_peer_config_t **peer, **next, **new_peer, **new_next; for (peer = old_peers; *peer; peer = next) { next = &(*peer)->next; /* don't touch statically configured peers */ if (!(*peer)->config_source_dir) continue; /* search for each peer in the list of new peers */ for (new_peer = new_peers; *new_peer; new_peer = new_next) { new_next = &(*new_peer)->next; if (((*peer)->config_source_dir == (*new_peer)->config_source_dir) && strequal((*peer)->name, (*new_peer)->name)) { if (fastd_peer_config_equal(*peer, *new_peer)) { pr_verbose(ctx, "peer `%s' unchanged", (*peer)->name); fastd_peer_config_t *free_peer = *new_peer; *new_peer = *new_next; fastd_peer_config_free(free_peer); peer = NULL; } else { pr_verbose(ctx, "peer `%s' changed, resetting", (*peer)->name); new_peer = NULL; } break; } } /* no new peer was found, or the old one has changed */ if (peer && (!new_peer || !*new_peer)) { pr_verbose(ctx, "removing peer `%s'", (*peer)->name); fastd_peer_config_t *free_peer = *peer; *peer = *next; next = peer; fastd_peer_config_purge(ctx, free_peer); } } } static void peer_dirs_handle_new_peers(fastd_context_t *ctx UNUSED, fastd_peer_config_t **peers, fastd_peer_config_t *new_peers) { fastd_peer_config_t *peer; for (peer = new_peers; peer; peer = peer->next) { if (peer->next) continue; peer->next = *peers; *peers = new_peers; return; } } void fastd_config_load_peer_dirs(fastd_context_t *ctx, fastd_config_t *conf) { fastd_config_t temp_conf; temp_conf.peer_group = conf->peer_group; temp_conf.peers = NULL; peer_dirs_read_peer_group(ctx, &temp_conf); peer_dirs_handle_old_peers(ctx, &conf->peers, &temp_conf.peers); peer_dirs_handle_new_peers(ctx, &conf->peers, temp_conf.peers); assess_peers(ctx, conf); } void fastd_config_release(fastd_context_t *ctx, fastd_config_t *conf) { while (conf->peers) fastd_peer_config_delete(ctx, conf); while (conf->log_files) { fastd_log_file_t *next = conf->log_files->next; free(conf->log_files->filename); free(conf->log_files); conf->log_files = next; } while (conf->bind_addrs) { fastd_bind_address_t *next = conf->bind_addrs->next; free(conf->bind_addrs->bindtodev); free(conf->bind_addrs); conf->bind_addrs = next; } free_peer_group(conf->peer_group); free(conf->user); free(conf->group); free(conf->groups); free(conf->ifname); free(conf->secret); free(conf->on_pre_up); free(conf->on_pre_up_dir); free(conf->on_up); free(conf->on_up_dir); free(conf->on_down); free(conf->on_down_dir); free(conf->on_post_down); free(conf->on_post_down_dir); free(conf->on_establish); free(conf->on_establish_dir); free(conf->on_disestablish); free(conf->on_disestablish_dir); free(conf->on_verify); free(conf->on_verify_dir); free(conf->protocol_config); free(conf->log_syslog_ident); }