src/lib/misc.c

/*-
 * Copyright (c) 2009,2010 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Alistair Crooks (agc@NetBSD.org)
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */
/*
 * Copyright (c) 2005-2008 Nominet UK (www.nic.uk)
 * All rights reserved.
 * Contributors: Ben Laurie, Rachel Willmer. The Contributors have asserted
 * their moral rights under the UK Copyright Design and Patents Act 1988 to
 * be recorded as the authors of this copyright work.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License.
 *
 * You may obtain a copy of the License at
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/** \file
 */
#include "config.h"

#ifdef HAVE_SYS_CDEFS_H
#include <sys/cdefs.h>
#endif

#if defined(__NetBSD__)
__COPYRIGHT("@(#) Copyright (c) 2009 The NetBSD Foundation, Inc. All rights reserved.");
__RCSID("$NetBSD: misc.c,v 1.28 2010/04/02 15:28:16 christos Exp $");
#endif

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_OPENSSL_RAND_H
#include <openssl/rand.h>
#endif

#include "errors.h"
#include "packet.h"
#include "crypto.h"
#include "create.h"
#include "fastctype.h"
#include "packet-parse.h"
#include "packet-show.h"
#include "signature.h"
#include "netpgpsdk.h"
#include "netpgpdefs.h"
#include "memory.h"
#include "readerwriter.h"
#include "version.h"
#include "netpgpdigest.h"

#ifdef WIN32
#define vsnprintf _vsnprintf
#endif


typedef struct {
	__ops_keyring_t  *keyring;
} accumulate_t;

/**
 * \ingroup Core_Callbacks
 */
static __ops_cb_ret_t
accumulate_cb(const __ops_packet_t *pkt, __ops_cbdata_t *cbinfo)
{
	const __ops_contents_t	*content = &pkt->u;
	__ops_keyring_t		*keyring;
	accumulate_t		*accumulate;

	accumulate = __ops_callback_arg(cbinfo);
	keyring = accumulate->keyring;
	switch (pkt->tag) {
	case OPS_PTAG_CT_PUBLIC_KEY:
	case OPS_PTAG_CT_SECRET_KEY:
	case OPS_PTAG_CT_ENCRYPTED_SECRET_KEY:
		if (__ops_get_debug_level(__FILE__)) {
			(void) fprintf(stderr, "Creating key %u - tag %u\n",
				keyring->keyc, pkt->tag);
		}
		if (pkt->tag == OPS_PTAG_CT_PUBLIC_KEY) {
			__ops_add_to_pubring(keyring, &content->pubkey);
		} else {
			__ops_add_to_secring(keyring, &content->seckey);
		}
		return OPS_KEEP_MEMORY;
	case OPS_PTAG_CT_USER_ID:
		if (__ops_get_debug_level(__FILE__)) {
			(void) fprintf(stderr, "User ID: %s for key %d\n",
					content->userid.userid,
					keyring->keyc - 1);
		}
		if (keyring->keyc > 0) {
			__ops_add_userid(&keyring->keys[keyring->keyc - 1],
						&content->userid);
			return OPS_KEEP_MEMORY;
		}
		OPS_ERROR(cbinfo->errors, OPS_E_P_NO_USERID, "No userid found");
		return OPS_KEEP_MEMORY;

	case OPS_PARSER_PACKET_END:
		if (keyring->keyc > 0) {
			__ops_add_subpacket(&keyring->keys[keyring->keyc - 1],
						&content->packet);
			return OPS_KEEP_MEMORY;
		}
		return OPS_RELEASE_MEMORY;

	case OPS_PARSER_ERROR:
		(void) fprintf(stderr, "Error: %s\n", content->error.error);
		return OPS_FINISHED;

	case OPS_PARSER_ERRCODE:
		(void) fprintf(stderr, "parse error: %s\n",
				__ops_errcode(content->errcode.errcode));
		break;

	default:
		break;
	}

	/* XXX: we now exclude so many things, we should either drop this or */
	/* do something to pass on copies of the stuff we keep */
	return __ops_stacked_callback(pkt, cbinfo);
}

/**
 * \ingroup Core_Parse
 *
 * Parse packets from an input stream until EOF or error.
 *
 * Key data found in the parsed data is added to #keyring.
 *
 * \param keyring Pointer to an existing keyring
 * \param parse Options to use when parsing
*/
int
__ops_parse_and_accumulate(__ops_keyring_t *keyring, __ops_stream_t *parse)
{
	accumulate_t	accumulate;
	const int	printerrors = 1;
	int             ret;

	if (parse->readinfo.accumulate) {
		(void) fprintf(stderr,
			"__ops_parse_and_accumulate: already init\n");
		return 0;
	}

	(void) memset(&accumulate, 0x0, sizeof(accumulate));

	accumulate.keyring = keyring;

	__ops_callback_push(parse, accumulate_cb, &accumulate);
	parse->readinfo.accumulate = 1;
	ret = __ops_parse(parse, !printerrors);

	return ret;
}


/** \file
 * \brief Error Handling
 */
#define ERRNAME(code)	{ code, #code }

static __ops_errcode_name_map_t errcode_name_map[] = {
	ERRNAME(OPS_E_OK),
	ERRNAME(OPS_E_FAIL),
	ERRNAME(OPS_E_SYSTEM_ERROR),
	ERRNAME(OPS_E_UNIMPLEMENTED),

	ERRNAME(OPS_E_R),
	ERRNAME(OPS_E_R_READ_FAILED),
	ERRNAME(OPS_E_R_EARLY_EOF),
	ERRNAME(OPS_E_R_BAD_FORMAT),
	ERRNAME(OPS_E_R_UNCONSUMED_DATA),

	ERRNAME(OPS_E_W),
	ERRNAME(OPS_E_W_WRITE_FAILED),
	ERRNAME(OPS_E_W_WRITE_TOO_SHORT),

	ERRNAME(OPS_E_P),
	ERRNAME(OPS_E_P_NOT_ENOUGH_DATA),
	ERRNAME(OPS_E_P_UNKNOWN_TAG),
	ERRNAME(OPS_E_P_PACKET_CONSUMED),
	ERRNAME(OPS_E_P_MPI_FORMAT_ERROR),

	ERRNAME(OPS_E_C),

	ERRNAME(OPS_E_V),
	ERRNAME(OPS_E_V_BAD_SIGNATURE),
	ERRNAME(OPS_E_V_NO_SIGNATURE),
	ERRNAME(OPS_E_V_UNKNOWN_SIGNER),

	ERRNAME(OPS_E_ALG),
	ERRNAME(OPS_E_ALG_UNSUPPORTED_SYMMETRIC_ALG),
	ERRNAME(OPS_E_ALG_UNSUPPORTED_PUBLIC_KEY_ALG),
	ERRNAME(OPS_E_ALG_UNSUPPORTED_SIGNATURE_ALG),
	ERRNAME(OPS_E_ALG_UNSUPPORTED_HASH_ALG),

	ERRNAME(OPS_E_PROTO),
	ERRNAME(OPS_E_PROTO_BAD_SYMMETRIC_DECRYPT),
	ERRNAME(OPS_E_PROTO_UNKNOWN_SS),
	ERRNAME(OPS_E_PROTO_CRITICAL_SS_IGNORED),
	ERRNAME(OPS_E_PROTO_BAD_PUBLIC_KEY_VRSN),
	ERRNAME(OPS_E_PROTO_BAD_SIGNATURE_VRSN),
	ERRNAME(OPS_E_PROTO_BAD_ONE_PASS_SIG_VRSN),
	ERRNAME(OPS_E_PROTO_BAD_PKSK_VRSN),
	ERRNAME(OPS_E_PROTO_DECRYPTED_MSG_WRONG_LEN),
	ERRNAME(OPS_E_PROTO_BAD_SK_CHECKSUM),

	{0x00, NULL},		/* this is the end-of-array marker */
};

/**
 * \ingroup Core_Errors
 * \brief returns error code name
 * \param errcode
 * \return error code name or "Unknown"
 */
const char     *
__ops_errcode(const __ops_errcode_t errcode)
{
	return (__ops_str_from_map((int) errcode,
			(__ops_map_t *) errcode_name_map));
}

/* generic grab new storage function */
void *
__ops_new(size_t size)
{
	void	*vp;

	if ((vp = calloc(1, size)) == NULL) {
		(void) fprintf(stderr,
			"allocation failure for %" PRIsize "u bytes", size);
	}
	return vp;
}

/**
 * \ingroup Core_Errors
 * \brief Pushes the given error on the given errorstack
 * \param errstack Error stack to use
 * \param errcode Code of error to push
 * \param sys_errno System errno (used if errcode=OPS_E_SYSTEM_ERROR)
 * \param file Source filename where error occurred
 * \param line Line in source file where error occurred
 * \param fmt Comment
 *
 */

void
__ops_push_error(__ops_error_t **errstack, __ops_errcode_t errcode,
		int sys_errno, const char *file, int line, const char *fmt,...)
{
	/* first get the varargs and generate the comment */
	__ops_error_t  *err;
	unsigned	maxbuf = 128;
	va_list		args;
	char           *comment;

	if ((comment = calloc(1, maxbuf + 1)) == NULL) {
		(void) fprintf(stderr, "calloc comment failure\n");
		return;
	}

	va_start(args, fmt);
	vsnprintf(comment, maxbuf + 1, fmt, args);
	va_end(args);

	/* alloc a new error and add it to the top of the stack */

	if ((err = calloc(1, sizeof(*err))) == NULL) {
		(void) fprintf(stderr, "calloc comment failure\n");
		return;
	}

	err->next = *errstack;
	*errstack = err;

	/* fill in the details */
	err->errcode = errcode;
	err->sys_errno = sys_errno;
	err->file = file;
	err->line = line;

	err->comment = comment;
}

/**
\ingroup Core_Errors
\brief print this error
\param err Error to print
*/
void
__ops_print_error(__ops_error_t *err)
{
	printf("%s:%d: ", err->file, err->line);
	if (err->errcode == OPS_E_SYSTEM_ERROR) {
		printf("system error %d returned from %s()\n", err->sys_errno,
		       err->comment);
	} else {
		printf("%s, %s\n", __ops_errcode(err->errcode), err->comment);
	}
}

/**
\ingroup Core_Errors
\brief Print all errors on stack
\param errstack Error stack to print
*/
void
__ops_print_errors(__ops_error_t *errstack)
{
	__ops_error_t    *err;

	for (err = errstack; err != NULL; err = err->next) {
		__ops_print_error(err);
	}
}

/**
\ingroup Core_Errors
\brief Return 1 if given error is present anywhere on stack
\param errstack Error stack to check
\param errcode Error code to look for
\return 1 if found; else 0
*/
int
__ops_has_error(__ops_error_t *errstack, __ops_errcode_t errcode)
{
	__ops_error_t    *err;

	for (err = errstack; err != NULL; err = err->next) {
		if (err->errcode == errcode) {
			return 1;
		}
	}
	return 0;
}

/**
\ingroup Core_Errors
\brief Frees all errors on stack
\param errstack Error stack to free
*/
void
__ops_free_errors(__ops_error_t *errstack)
{
	__ops_error_t    *next;

	while (errstack != NULL) {
		next = errstack->next;
		free(errstack->comment);
		free(errstack);
		errstack = next;
	}
}

/** \file
 */

/**
 * \ingroup Core_Keys
 * \brief Calculate a public key fingerprint.
 * \param fp Where to put the calculated fingerprint
 * \param key The key for which the fingerprint is calculated
 */

void
__ops_fingerprint(__ops_fingerprint_t *fp, const __ops_pubkey_t *key)
{
	if (key->version == 2 || key->version == 3) {
		unsigned char  *bn;
		size_t		n;
		__ops_hash_t	md5;

		if (key->alg != OPS_PKA_RSA &&
		    key->alg != OPS_PKA_RSA_ENCRYPT_ONLY &&
		    key->alg != OPS_PKA_RSA_SIGN_ONLY) {
			(void) fprintf(stderr,
				"__ops_fingerprint: bad algorithm\n");
			return;
		}

		__ops_hash_md5(&md5);
		if (!md5.init(&md5)) {
			(void) fprintf(stderr,
				"__ops_fingerprint: bad md5 alloc\n");
				return;
		}

		n = (size_t) BN_num_bytes(key->key.rsa.n);
		if ((bn = calloc(1, n)) == NULL) {
			(void) fprintf(stderr,
				"__ops_fingerprint: bad bn alloc\n");
			return;
		}
		BN_bn2bin(key->key.rsa.n, bn);
		md5.add(&md5, bn, n);
		free(bn);

		n = (size_t) BN_num_bytes(key->key.rsa.e);
		if ((bn = calloc(1, n)) == NULL) {
			(void) fprintf(stderr,
				"__ops_fingerprint: bad bn alloc 2\n");
			return;
		}
		BN_bn2bin(key->key.rsa.e, bn);
		md5.add(&md5, bn, n);
		free(bn);

		md5.finish(&md5, fp->fingerprint);
		fp->length = 16;
	} else {
		__ops_memory_t	*mem = __ops_memory_new();
		__ops_hash_t	 sha1;
		size_t		 len;

		__ops_build_pubkey(mem, key, 0);

		if (__ops_get_debug_level(__FILE__)) {
			fprintf(stderr, "-> creating key fingerprint\n");
		}
		__ops_hash_sha1(&sha1);
		if (!sha1.init(&sha1)) {
			(void) fprintf(stderr,
				"__ops_fingerprint: bad sha1 alloc\n");
			return;
		}

		len = __ops_mem_len(mem);

		__ops_hash_add_int(&sha1, 0x99, 1);
		__ops_hash_add_int(&sha1, len, 2);
		sha1.add(&sha1, __ops_mem_data(mem), len);
		sha1.finish(&sha1, fp->fingerprint);

		if (__ops_get_debug_level(__FILE__)) {
			fprintf(stderr, "<- finished making key fingerprint\n");
		}
		fp->length = OPS_FINGERPRINT_SIZE;

		__ops_memory_free(mem);
	}
}

/**
 * \ingroup Core_Keys
 * \brief Calculate the Key ID from the public key.
 * \param keyid Space for the calculated ID to be stored
 * \param key The key for which the ID is calculated
 */

void
__ops_keyid(uint8_t *keyid, const size_t idlen, const __ops_pubkey_t *key)
{
	__ops_fingerprint_t finger;

	if (key->version == 2 || key->version == 3) {
		unsigned	n;
		uint8_t		bn[NETPGP_BUFSIZ];

		n = (unsigned) BN_num_bytes(key->key.rsa.n);
		if (n > sizeof(bn)) {
			(void) fprintf(stderr, "__ops_keyid: bad num bytes\n");
			return;
		}
		if (key->alg != OPS_PKA_RSA &&
		    key->alg != OPS_PKA_RSA_ENCRYPT_ONLY &&
		    key->alg != OPS_PKA_RSA_SIGN_ONLY) {
			(void) fprintf(stderr, "__ops_keyid: bad algorithm\n");
			return;
		}
		BN_bn2bin(key->key.rsa.n, bn);
		(void) memcpy(keyid, bn + n - idlen, idlen);
	} else {
		__ops_fingerprint(&finger, key);
		(void) memcpy(keyid,
				finger.fingerprint + finger.length - idlen,
				idlen);
	}
}

/**
\ingroup Core_Hashes
\brief Add to the hash
\param hash Hash to add to
\param n Int to add
\param length Length of int in bytes
*/
void
__ops_hash_add_int(__ops_hash_t *hash, unsigned n, unsigned length)
{
	uint8_t   c;

	while (length--) {
		c = n >> (length * 8);
		hash->add(hash, &c, 1);
	}
}

/**
\ingroup Core_Hashes
\brief Setup hash for given hash algorithm
\param hash Hash to set up
\param alg Hash algorithm to use
*/
void
__ops_hash_any(__ops_hash_t *hash, __ops_hash_alg_t alg)
{
	switch (alg) {
	case OPS_HASH_MD5:
		__ops_hash_md5(hash);
		break;

	case OPS_HASH_SHA1:
		__ops_hash_sha1(hash);
		break;

	case OPS_HASH_SHA256:
		__ops_hash_sha256(hash);
		break;

	case OPS_HASH_SHA384:
		__ops_hash_sha384(hash);
		break;

	case OPS_HASH_SHA512:
		__ops_hash_sha512(hash);
		break;

	case OPS_HASH_SHA224:
		__ops_hash_sha224(hash);
		break;

	default:
		(void) fprintf(stderr, "__ops_hash_any: bad algorithm\n");
	}
}

/**
\ingroup Core_Hashes
\brief Returns size of hash for given hash algorithm
\param alg Hash algorithm to use
\return Size of hash algorithm in bytes
*/
unsigned
__ops_hash_size(__ops_hash_alg_t alg)
{
	switch (alg) {
	case OPS_HASH_MD5:
		return 16;

	case OPS_HASH_SHA1:
		return 20;

	case OPS_HASH_SHA256:
		return 32;

	case OPS_HASH_SHA224:
		return 28;

	case OPS_HASH_SHA512:
		return 64;

	case OPS_HASH_SHA384:
		return 48;

	default:
		(void) fprintf(stderr, "__ops_hash_size: bad algorithm\n");
	}

	return 0;
}

/**
\ingroup Core_Hashes
\brief Returns hash enum corresponding to given string
\param hash Text name of hash algorithm i.e. "SHA1"
\returns Corresponding enum i.e. OPS_HASH_SHA1
*/
__ops_hash_alg_t
__ops_str_to_hash_alg(const char *hash)
{
	if (hash == NULL) {
		return OPS_DEFAULT_HASH_ALGORITHM;
	}
	if (netpgp_strcasecmp(hash, "SHA1") == 0) {
		return OPS_HASH_SHA1;
	}
	if (netpgp_strcasecmp(hash, "MD5") == 0) {
		return OPS_HASH_MD5;
	}
	if (netpgp_strcasecmp(hash, "SHA256") == 0) {
		return OPS_HASH_SHA256;
	}
	/*
        if (netpgp_strcasecmp(hash,"SHA224") == 0) {
		return OPS_HASH_SHA224;
	}
        */
	if (netpgp_strcasecmp(hash, "SHA512") == 0) {
		return OPS_HASH_SHA512;
	}
	if (netpgp_strcasecmp(hash, "SHA384") == 0) {
		return OPS_HASH_SHA384;
	}
	return OPS_HASH_UNKNOWN;
}

/**
\ingroup Core_Hashes
\brief Hash given data
\param out Where to write the hash
\param alg Hash algorithm to use
\param in Data to hash
\param length Length of data
\return Size of hash created
*/
unsigned
__ops_hash(uint8_t *out, __ops_hash_alg_t alg, const void *in, size_t length)
{
	__ops_hash_t      hash;

	__ops_hash_any(&hash, alg);
	if (!hash.init(&hash)) {
		(void) fprintf(stderr, "__ops_hash: bad alloc\n");
		/* we'll just continue here - don't want to return a 0 hash */
		/* XXX - agc - no way to return failure */
	}
	hash.add(&hash, in, length);
	return hash.finish(&hash, out);
}

/**
\ingroup Core_Hashes
\brief Calculate hash for MDC packet
\param preamble Preamble to hash
\param sz_preamble Size of preamble
\param plaintext Plaintext to hash
\param sz_plaintext Size of plaintext
\param hashed Resulting hash
*/
void
__ops_calc_mdc_hash(const uint8_t *preamble,
			const size_t sz_preamble,
			const uint8_t *plaintext,
			const unsigned sz_plaintext,
			uint8_t *hashed)
{
	__ops_hash_t	hash;
	uint8_t		c;

	if (__ops_get_debug_level(__FILE__)) {
		unsigned	i;

		(void) fprintf(stderr, "__ops_calc_mdc_hash():\n");
		(void) fprintf(stderr, "\npreamble: ");
		for (i = 0; i < sz_preamble; i++)
			(void) fprintf(stderr, " 0x%02x", preamble[i]);
		(void) fprintf(stderr, "\n");
		(void) fprintf(stderr, "\nplaintext (len=%u): ", sz_plaintext);
		for (i = 0; i < sz_plaintext; i++)
			(void) fprintf(stderr, " 0x%02x", plaintext[i]);
		(void) fprintf(stderr, "\n");
	}
	/* init */
	__ops_hash_any(&hash, OPS_HASH_SHA1);
	if (!hash.init(&hash)) {
		(void) fprintf(stderr, "__ops_calc_mdc_hash: bad alloc\n");
		/* we'll just continue here - it will die anyway */
		/* agc - XXX - no way to return failure */
	}

	/* preamble */
	hash.add(&hash, preamble, sz_preamble);
	/* plaintext */
	hash.add(&hash, plaintext, sz_plaintext);
	/* MDC packet tag */
	c = MDC_PKT_TAG;
	hash.add(&hash, &c, 1);
	/* MDC packet len */
	c = OPS_SHA1_HASH_SIZE;
	hash.add(&hash, &c, 1);

	/* finish */
	hash.finish(&hash, hashed);

	if (__ops_get_debug_level(__FILE__)) {
		unsigned	i;

		(void) fprintf(stderr, "\nhashed (len=%d): ",
				OPS_SHA1_HASH_SIZE);
		for (i = 0; i < OPS_SHA1_HASH_SIZE; i++) {
			(void) fprintf(stderr, " 0x%02x", hashed[i]);
		}
		(void) fprintf(stderr, "\n");
	}
}

/**
\ingroup HighLevel_Supported
\brief Is this Hash Algorithm supported?
\param hash_alg Hash Algorithm to check
\return 1 if supported; else 0
*/
unsigned
__ops_is_hash_alg_supported(const __ops_hash_alg_t *hash_alg)
{
	switch (*hash_alg) {
	case OPS_HASH_MD5:
	case OPS_HASH_SHA1:
	case OPS_HASH_SHA256:
		return 1;

	default:
		return 0;
	}
}

void
__ops_random(void *dest, size_t length)
{
	RAND_bytes(dest, (int)length);
}

/**
\ingroup HighLevel_Memory
\brief Memory to initialise
\param mem memory to initialise
\param needed Size to initialise to
*/
void
__ops_memory_init(__ops_memory_t *mem, size_t needed)
{
	uint8_t	*temp;

	mem->length = 0;
	if (mem->buf) {
		if (mem->allocated < needed) {
			if ((temp = realloc(mem->buf, needed)) == NULL) {
				(void) fprintf(stderr, "__ops_memory_init: bad alloc\n");
			} else {
				mem->buf = temp;
				mem->allocated = needed;
			}
		}
	} else {
		if ((mem->buf = calloc(1, needed)) == NULL) {
			(void) fprintf(stderr, "__ops_memory_init: bad alloc\n");
		} else {
			mem->allocated = needed;
		}
	}
}

/**
\ingroup HighLevel_Memory
\brief Pad memory to required length
\param mem Memory to use
\param length New size
*/
void
__ops_memory_pad(__ops_memory_t *mem, size_t length)
{
	uint8_t	*temp;

	if (mem->allocated < mem->length) {
		(void) fprintf(stderr, "__ops_memory_pad: bad alloc in\n");
		return;
	}
	if (mem->allocated < mem->length + length) {
		mem->allocated = mem->allocated * 2 + length;
		temp = realloc(mem->buf, mem->allocated);
		if (temp == NULL) {
			(void) fprintf(stderr, "__ops_memory_pad: bad alloc\n");
		} else {
			mem->buf = temp;
		}
	}
	if (mem->allocated < mem->length + length) {
		(void) fprintf(stderr, "__ops_memory_pad: bad alloc out\n");
	}
}

/**
\ingroup HighLevel_Memory
\brief Add data to memory
\param mem Memory to which to add
\param src Data to add
\param length Length of data to add
*/
void
__ops_memory_add(__ops_memory_t *mem, const uint8_t *src, size_t length)
{
	__ops_memory_pad(mem, length);
	(void) memcpy(mem->buf + mem->length, src, length);
	mem->length += length;
}

/* XXX: this could be refactored via the writer, but an awful lot of */
/* hoops to jump through for 2 lines of code! */
void
__ops_memory_place_int(__ops_memory_t *mem, unsigned offset, unsigned n,
		     size_t length)
{
	if (mem->allocated < offset + length) {
		(void) fprintf(stderr,
			"__ops_memory_place_int: bad alloc\n");
	} else {
		while (length-- > 0) {
			mem->buf[offset++] = n >> (length * 8);
		}
	}
}

/**
 * \ingroup HighLevel_Memory
 * \brief Retains allocated memory and set length of stored data to zero.
 * \param mem Memory to clear
 * \sa __ops_memory_release()
 * \sa __ops_memory_free()
 */
void
__ops_memory_clear(__ops_memory_t *mem)
{
	mem->length = 0;
}

/**
\ingroup HighLevel_Memory
\brief Free memory and associated data
\param mem Memory to free
\note This does not free mem itself
\sa __ops_memory_clear()
\sa __ops_memory_free()
*/
void
__ops_memory_release(__ops_memory_t *mem)
{
	if (mem->mmapped) {
		(void) munmap(mem->buf, mem->length);
	} else {
		free(mem->buf);
	}
	mem->buf = NULL;
	mem->length = 0;
}

void
__ops_memory_make_packet(__ops_memory_t *out, __ops_content_tag_t tag)
{
	size_t          extra;

	extra = (out->length < 192) ? 1 : (out->length < 8192 + 192) ? 2 : 5;
	__ops_memory_pad(out, extra + 1);
	memmove(out->buf + extra + 1, out->buf, out->length);

	out->buf[0] = OPS_PTAG_ALWAYS_SET | OPS_PTAG_NEW_FORMAT | tag;

	if (out->length < 192) {
		out->buf[1] = out->length;
	} else if (out->length < 8192 + 192) {
		out->buf[1] = ((out->length - 192) >> 8) + 192;
		out->buf[2] = out->length - 192;
	} else {
		out->buf[1] = 0xff;
		out->buf[2] = out->length >> 24;
		out->buf[3] = out->length >> 16;
		out->buf[4] = out->length >> 8;
		out->buf[5] = out->length;
	}

	out->length += extra + 1;
}

/**
   \ingroup HighLevel_Memory
   \brief Create a new zeroed __ops_memory_t
   \return Pointer to new __ops_memory_t
   \note Free using __ops_memory_free() after use.
   \sa __ops_memory_free()
*/

__ops_memory_t   *
__ops_memory_new(void)
{
	return calloc(1, sizeof(__ops_memory_t));
}

/**
   \ingroup HighLevel_Memory
   \brief Free memory ptr and associated memory
   \param mem Memory to be freed
   \sa __ops_memory_release()
   \sa __ops_memory_clear()
*/

void
__ops_memory_free(__ops_memory_t *mem)
{
	__ops_memory_release(mem);
	free(mem);
}

/**
   \ingroup HighLevel_Memory
   \brief Get length of data stored in __ops_memory_t struct
   \return Number of bytes in data
*/
size_t
__ops_mem_len(const __ops_memory_t *mem)
{
	return mem->length;
}

/**
   \ingroup HighLevel_Memory
   \brief Get data stored in __ops_memory_t struct
   \return Pointer to data
*/
void *
__ops_mem_data(__ops_memory_t *mem)
{
	return mem->buf;
}

/* read a gile into an __ops_memory_t */
int
__ops_mem_readfile(__ops_memory_t *mem, const char *f)
{
	struct stat	 st;
	FILE		*fp;
	int		 cc;

	if ((fp = fopen(f, "rb")) == NULL) {
		(void) fprintf(stderr,
				"__ops_mem_readfile: can't open \"%s\"\n", f);
		return 0;
	}
	(void) fstat(fileno(fp), &st);
	mem->allocated = (size_t)st.st_size;
	mem->buf = mmap(NULL, mem->allocated, PROT_READ,
				MAP_PRIVATE | MAP_FILE, fileno(fp), 0);
	if (mem->buf == MAP_FAILED) {
		/* mmap failed for some reason - try to allocate memory */
		if ((mem->buf = calloc(1, mem->allocated)) == NULL) {
			(void) fprintf(stderr, "__ops_mem_readfile: calloc\n");
			(void) fclose(fp);
			return 0;
		}
		/* read into contents of mem */
		for (mem->length = 0 ;
		     (cc = read(fileno(fp), &mem->buf[mem->length],
					mem->allocated - mem->length)) > 0 ;
		     mem->length += (size_t)cc) {
		}
	} else {
		mem->length = mem->allocated;
		mem->mmapped = 1;
	}
	(void) fclose(fp);
	return (mem->allocated == mem->length);
}

typedef struct {
	uint16_t  sum;
} sum16_t;


/**
 * Searches the given map for the given type.
 * Returns a human-readable descriptive string if found,
 * returns NULL if not found
 *
 * It is the responsibility of the calling function to handle the
 * error case sensibly (i.e. don't just print out the return string.
 *
 */
static const char *
str_from_map_or_null(int type, __ops_map_t *map)
{
	__ops_map_t      *row;

	for (row = map; row->string != NULL; row++) {
		if (row->type == type) {
			return row->string;
		}
	}
	return NULL;
}

/**
 * \ingroup Core_Print
 *
 * Searches the given map for the given type.
 * Returns a readable string if found, "Unknown" if not.
 */

const char     *
__ops_str_from_map(int type, __ops_map_t *map)
{
	const char     *str;

	str = str_from_map_or_null(type, map);
	return (str) ? str : "Unknown";
}

void
hexdump(FILE *fp, const uint8_t *src, size_t length, const char *sep)
{
	unsigned i;

	for (i = 0 ; i < length ; i += 2) {
		(void) fprintf(fp, "%02x", *src++);
		(void) fprintf(fp, "%02x%s", *src++, sep);
	}
}

/**
 * \ingroup HighLevel_Functions
 * \brief Initialises OpenPGP::SDK. To be called before any other OPS function.
 *
 * Initialises OpenPGP::SDK and the underlying openssl library.
 */

void
__ops_init(void)
{
	__ops_crypto_init();
}

/**
 * \ingroup HighLevel_Functions
 * \brief Closes down OpenPGP::SDK.
 *
 * Close down OpenPGP:SDK, release any resources under the control of
 * the library. No OpenPGP:SDK function other than __ops_init() should
 * be called after this function.
 */

void
__ops_finish(void)
{
	__ops_crypto_finish();
}

static int
sum16_reader(void *dest_, size_t length, __ops_error_t **errors,
	     __ops_reader_t *readinfo, __ops_cbdata_t *cbinfo)
{
	const uint8_t	*dest = dest_;
	sum16_t		*arg = __ops_reader_get_arg(readinfo);
	int		 r;
	int		 n;

	r = __ops_stacked_read(dest_, length, errors, readinfo, cbinfo);
	if (r < 0) {
		return r;
	}
	for (n = 0; n < r; ++n) {
		arg->sum = (arg->sum + dest[n]) & 0xffff;
	}
	return r;
}

static void
sum16_destroyer(__ops_reader_t *readinfo)
{
	free(__ops_reader_get_arg(readinfo));
}

/**
   \ingroup Internal_Readers_Sum16
   \param stream Parse settings
*/

void
__ops_reader_push_sum16(__ops_stream_t *stream)
{
	sum16_t    *arg;

	if ((arg = calloc(1, sizeof(*arg))) == NULL) {
		(void) fprintf(stderr, "__ops_reader_push_sum16: bad alloc\n");
	} else {
		__ops_reader_push(stream, sum16_reader, sum16_destroyer, arg);
	}
}

/**
   \ingroup Internal_Readers_Sum16
   \param stream Parse settings
   \return sum
*/
uint16_t
__ops_reader_pop_sum16(__ops_stream_t *stream)
{
	uint16_t	 sum;
	sum16_t		*arg;

	arg = __ops_reader_get_arg(__ops_readinfo(stream));
	sum = arg->sum;
	__ops_reader_pop(stream);
	free(arg);
	return sum;
}

/* small useful functions for setting the file-level debugging levels */
/* if the debugv list contains the filename in question, we're debugging it */

enum {
	MAX_DEBUG_NAMES = 32
};

static int      debugc;
static char    *debugv[MAX_DEBUG_NAMES];

/* set the debugging level per filename */
int
__ops_set_debug_level(const char *f)
{
	const char     *name;
	int             i;

	if (f == NULL) {
		f = "all";
	}
	if ((name = strrchr(f, '/')) == NULL) {
		name = f;
	} else {
		name += 1;
	}
	for (i = 0; i < debugc && i < MAX_DEBUG_NAMES; i++) {
		if (strcmp(debugv[i], name) == 0) {
			return 1;
		}
	}
	if (i == MAX_DEBUG_NAMES) {
		return 0;
	}
	debugv[debugc++] = netpgp_strdup(name);
	return 1;
}

/* get the debugging level per filename */
int
__ops_get_debug_level(const char *f)
{
	const char     *name;
	int             i;

	if ((name = strrchr(f, '/')) == NULL) {
		name = f;
	} else {
		name += 1;
	}
	for (i = 0; i < debugc; i++) {
		if (strcmp(debugv[i], "all") == 0 ||
		    strcmp(debugv[i], name) == 0) {
			return 1;
		}
	}
	return 0;
}

/* return the version for the library */
const char *
__ops_get_info(const char *type)
{
	if (strcmp(type, "version") == 0) {
		return NETPGP_VERSION_STRING;
	}
	if (strcmp(type, "maintainer") == 0) {
		return NETPGP_MAINTAINER;
	}
	return "[unknown]";
}

/* local version of asprintf so we don't have to play autoconf games */
int
__ops_asprintf(char **ret, const char *fmt, ...)
{
	va_list args;
	char    buf[120 * 1024];	/* XXX - "huge" buffer on stack */
	int     cc;

	va_start(args, fmt);
	cc = vsnprintf(buf, sizeof(buf), fmt, args);
	va_end(args);
	if ((*ret = calloc(1, (size_t)(cc + 1))) == NULL) {
		*ret = NULL;
		return -1;
	}
	(void) memcpy(*ret, buf, (size_t)cc);
	(*ret)[cc] = 0x0;
	return cc;
}

void
netpgp_log(const char *fmt, ...)
{
	va_list	 vp;
	time_t	 t;
	char	 buf[BUFSIZ * 2];
	int	 cc;

	(void) time(&t);
	cc = snprintf(buf, sizeof(buf), "%.24s: netpgp: ", ctime(&t));
	va_start(vp, fmt);
	(void) vsnprintf(&buf[cc], sizeof(buf) - (size_t)cc, fmt, vp);
	va_end(vp);
	/* do something with message */
	/* put into log buffer? */
}

/* portable replacement for strdup(3) */
char *
netpgp_strdup(const char *s)
{
	size_t	 len;
	char	*cp;

	len = strlen(s);
	if ((cp = calloc(1, len + 1)) != NULL) {
		(void) memcpy(cp, s, len);
		cp[len] = 0x0;
	}
	return cp;
}

/* portable replacement for strcasecmp(3) */
int
netpgp_strcasecmp(const char *s1, const char *s2)
{
	int	n;

	for (n = 0 ; *s1 && *s2 && (n = tolower(*s1) - tolower(*s2)) == 0 ; s1++, s2++) {
	}
	return n;
}