/*
   * Create default crypto algorithm instances.
   *
   * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   *
   * 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.
   *
   */
  
  #include <linux/crypto.h>
  #include <linux/ctype.h>
  #include <linux/err.h>
  #include <linux/init.h>

  #include <linux/kthread.h>

  #include <linux/module.h>
  #include <linux/notifier.h>
  #include <linux/rtnetlink.h>

  #include <linux/sched.h>

  #include <linux/string.h>

  
  #include "internal.h"
  
  struct cryptomgr_param {

  	struct rtattr *tb[CRYPTO_MAX_ATTRS + 2];

  
  	struct {
  		struct rtattr attr;
  		struct crypto_attr_type data;
  	} type;

  	union {

  		struct rtattr attr;

  		struct {
  			struct rtattr attr;
  			struct crypto_attr_alg data;
  		} alg;
  		struct {
  			struct rtattr attr;
  			struct crypto_attr_u32 data;
  		} nu32;
  	} attrs[CRYPTO_MAX_ATTRS];
  
  	char larval[CRYPTO_MAX_ALG_NAME];

  	char template[CRYPTO_MAX_ALG_NAME];
  };

  static int cryptomgr_probe(void *data)

  {

  	struct cryptomgr_param *param = data;

  	struct crypto_template *tmpl;
  	struct crypto_instance *inst;

  	int err;

  
  	tmpl = crypto_lookup_template(param->template);
  	if (!tmpl)
  		goto err;

  	do {

  		inst = tmpl->alloc(param->tb);

  		if (IS_ERR(inst))
  			err = PTR_ERR(inst);
  		else if ((err = crypto_register_instance(tmpl, inst)))
  			tmpl->free(inst);
  	} while (err == -EAGAIN && !signal_pending(current));

  
  	crypto_tmpl_put(tmpl);

  	if (err)
  		goto err;

  out:
  	kfree(param);

  	module_put_and_exit(0);

  
  err:

  	crypto_larval_error(param->larval, param->type.data.type,

  			    param->type.data.mask);

  	goto out;
  }
  
  static int cryptomgr_schedule_probe(struct crypto_larval *larval)
  {

  	struct task_struct *thread;

  	struct cryptomgr_param *param;
  	const char *name = larval->alg.cra_name;
  	const char *p;
  	unsigned int len;

  	int i;

  	if (!try_module_get(THIS_MODULE))
  		goto err;

  	param = kzalloc(sizeof(*param), GFP_KERNEL);

  	if (!param)

  		goto err_put_module;

  
  	for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
  		;
  
  	len = p - name;
  	if (!len || *p != '(')
  		goto err_free_param;
  
  	memcpy(param->template, name, len);

  	i = 0;
  	for (;;) {
  		int notnum = 0;

  		name = ++p;
  		len = 0;
  
  		for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
  			notnum |= !isdigit(*p);
  
  		if (*p == '(') {
  			int recursion = 0;
  
  			for (;;) {
  				if (!*++p)
  					goto err_free_param;
  				if (*p == '(')
  					recursion++;
  				else if (*p == ')' && !recursion--)
  					break;
  			}
  
  			notnum = 1;

  			p++;

  		}

  
  		len = p - name;

  		if (!len)
  			goto err_free_param;
  
  		if (notnum) {
  			param->attrs[i].alg.attr.rta_len =
  				sizeof(param->attrs[i].alg);
  			param->attrs[i].alg.attr.rta_type = CRYPTOA_ALG;
  			memcpy(param->attrs[i].alg.data.name, name, len);
  		} else {
  			param->attrs[i].nu32.attr.rta_len =
  				sizeof(param->attrs[i].nu32);
  			param->attrs[i].nu32.attr.rta_type = CRYPTOA_U32;
  			param->attrs[i].nu32.data.num =
  				simple_strtol(name, NULL, 0);
  		}
  
  		param->tb[i + 1] = &param->attrs[i].attr;
  		i++;

  		if (i >= CRYPTO_MAX_ATTRS)

  			goto err_free_param;
  
  		if (*p == ')')
  			break;
  
  		if (*p != ',')
  			goto err_free_param;

  	}

  	if (!i)

  		goto err_free_param;

  	param->tb[i + 1] = NULL;

  	param->type.attr.rta_len = sizeof(param->type);
  	param->type.attr.rta_type = CRYPTOA_TYPE;
  	param->type.data.type = larval->alg.cra_flags;
  	param->type.data.mask = larval->mask;

  	param->tb[0] = &param->type.attr;

  	memcpy(param->larval, larval->alg.cra_name, CRYPTO_MAX_ALG_NAME);

  	thread = kthread_run(cryptomgr_probe, param, "cryptomgr");
  	if (IS_ERR(thread))

  		goto err_free_param;

  
  	return NOTIFY_STOP;
  
  err_free_param:
  	kfree(param);

  err_put_module:
  	module_put(THIS_MODULE);

  err:
  	return NOTIFY_OK;
  }
  
  static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
  			    void *data)
  {
  	switch (msg) {
  	case CRYPTO_MSG_ALG_REQUEST:
  		return cryptomgr_schedule_probe(data);
  	}
  
  	return NOTIFY_DONE;
  }
  
  static struct notifier_block cryptomgr_notifier = {
  	.notifier_call = cryptomgr_notify,
  };
  
  static int __init cryptomgr_init(void)
  {
  	return crypto_register_notifier(&cryptomgr_notifier);
  }
  
  static void __exit cryptomgr_exit(void)
  {
  	int err = crypto_unregister_notifier(&cryptomgr_notifier);
  	BUG_ON(err);
  }
  
  module_init(cryptomgr_init);
  module_exit(cryptomgr_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Crypto Algorithm Manager");