diff options
Diffstat (limited to 'src/charon/plugins/resolve/resolve_handler.c')
| -rw-r--r-- | src/charon/plugins/resolve/resolve_handler.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/src/charon/plugins/resolve/resolve_handler.c b/src/charon/plugins/resolve/resolve_handler.c new file mode 100644 index 000000000..714c751a6 --- /dev/null +++ b/src/charon/plugins/resolve/resolve_handler.c @@ -0,0 +1,251 @@ +/* + * Copyright (C) 2009 Martin Willi + * Hochschule fuer Technik Rapperswil + * + * 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 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * 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. + */ + +#include "resolve_handler.h" + +#include <unistd.h> + +#include <daemon.h> +#include <threading/mutex.h> + +typedef struct private_resolve_handler_t private_resolve_handler_t; + +/** + * Private data of an resolve_handler_t object. + */ +struct private_resolve_handler_t { + + /** + * Public resolve_handler_t interface. + */ + resolve_handler_t public; + + /** + * resolv.conf file to use + */ + char *file; + + /** + * Mutex to access file exclusively + */ + mutex_t *mutex; +}; + +/** + * Implementation of attribute_handler_t.handle + */ +static bool handle(private_resolve_handler_t *this, identification_t *server, + configuration_attribute_type_t type, chunk_t data) +{ + FILE *in, *out; + char buf[1024]; + host_t *addr; + size_t len; + bool handled = FALSE; + + switch (type) + { + case INTERNAL_IP4_DNS: + addr = host_create_from_chunk(AF_INET, data, 0); + break; + case INTERNAL_IP6_DNS: + addr = host_create_from_chunk(AF_INET6, data, 0); + break; + default: + return FALSE; + } + + if (!addr || addr->is_anyaddr(addr)) + { + DESTROY_IF(addr); + return FALSE; + } + this->mutex->lock(this->mutex); + + in = fopen(this->file, "r"); + /* allows us to stream from in to out */ + unlink(this->file); + out = fopen(this->file, "w"); + if (out) + { + fprintf(out, "nameserver %H # by strongSwan, from %Y\n", addr, server); + DBG1(DBG_IKE, "installing DNS server %H to %s", addr, this->file); + handled = TRUE; + + /* copy rest of the file */ + if (in) + { + while ((len = fread(buf, 1, sizeof(buf), in))) + { + ignore_result(fwrite(buf, 1, len, out)); + } + } + fclose(out); + } + if (in) + { + fclose(in); + } + this->mutex->unlock(this->mutex); + addr->destroy(addr); + + if (!handled) + { + DBG1(DBG_IKE, "adding DNS server failed", this->file); + } + return handled; +} + +/** + * Implementation of attribute_handler_t.release + */ +static void release(private_resolve_handler_t *this, identification_t *server, + configuration_attribute_type_t type, chunk_t data) +{ + FILE *in, *out; + char line[1024], matcher[512], *pos; + host_t *addr; + int family; + + switch (type) + { + case INTERNAL_IP4_DNS: + family = AF_INET; + break; + case INTERNAL_IP6_DNS: + family = AF_INET6; + break; + default: + return; + } + + this->mutex->lock(this->mutex); + + in = fopen(this->file, "r"); + if (in) + { + /* allows us to stream from in to out */ + unlink(this->file); + out = fopen(this->file, "w"); + if (out) + { + addr = host_create_from_chunk(family, data, 0); + snprintf(matcher, sizeof(matcher), + "nameserver %H # by strongSwan, from %Y\n", + addr, server); + + /* copy all, but matching line */ + while ((pos = fgets(line, sizeof(line), in))) + { + if (strneq(line, matcher, strlen(matcher))) + { + DBG1(DBG_IKE, "removing DNS server %H from %s", + addr, this->file); + } + else + { + fputs(line, out); + } + } + addr->destroy(addr); + fclose(out); + } + fclose(in); + } + + this->mutex->unlock(this->mutex); +} + +/** + * Attribute enumerator implementation + */ +typedef struct { + /** implements enumerator_t interface */ + enumerator_t public; + /** virtual IP we are requesting */ + host_t *vip; +} attribute_enumerator_t; + +/** + * Implementation of create_attribute_enumerator().enumerate() + */ +static bool attribute_enumerate(attribute_enumerator_t *this, + configuration_attribute_type_t *type, chunk_t *data) +{ + switch (this->vip->get_family(this->vip)) + { + case AF_INET: + *type = INTERNAL_IP4_DNS; + break; + case AF_INET6: + *type = INTERNAL_IP6_DNS; + break; + default: + return FALSE; + } + *data = chunk_empty; + /* enumerate only once */ + this->public.enumerate = (void*)return_false; + return TRUE; +} + +/** + * Implementation of attribute_handler_t.create_attribute_enumerator + */ +static enumerator_t* create_attribute_enumerator(private_resolve_handler_t *this, + identification_t *server, host_t *vip) +{ + if (vip) + { + attribute_enumerator_t *enumerator; + + enumerator = malloc_thing(attribute_enumerator_t); + enumerator->public.enumerate = (void*)attribute_enumerate; + enumerator->public.destroy = (void*)free; + enumerator->vip = vip; + + return &enumerator->public; + } + return enumerator_create_empty(); +} + +/** + * Implementation of resolve_handler_t.destroy. + */ +static void destroy(private_resolve_handler_t *this) +{ + this->mutex->destroy(this->mutex); + free(this); +} + +/** + * See header + */ +resolve_handler_t *resolve_handler_create() +{ + private_resolve_handler_t *this = malloc_thing(private_resolve_handler_t); + + this->public.handler.handle = (bool(*)(attribute_handler_t*, identification_t*, configuration_attribute_type_t, chunk_t))handle; + this->public.handler.release = (void(*)(attribute_handler_t*, identification_t*, configuration_attribute_type_t, chunk_t))release; + this->public.handler.create_attribute_enumerator = (enumerator_t*(*)(attribute_handler_t*, identification_t *server, host_t *vip))create_attribute_enumerator; + this->public.destroy = (void(*)(resolve_handler_t*))destroy; + + this->mutex = mutex_create(MUTEX_TYPE_DEFAULT); + this->file = lib->settings->get_str(lib->settings, + "charon.plugins.resolve.file", RESOLV_CONF); + + return &this->public; +} + |