/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/* egg-buffer.c - Generic data buffer, used by openssh, gnome-keyring
Copyright (C) 2007 Stefan Walter
The Gnome Keyring Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The Gnome Keyring 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the Gnome Library; see the file COPYING.LIB. If not,
see <http://www.gnu.org/licenses/>.
Author: Stef Walter <stef@memberwebs.com>
*/
#include "config.h"
#include <string.h>
#include <stdarg.h>
#include "egg-buffer.h"
#define DEFAULT_ALLOCATOR ((EggBufferAllocator)realloc)
int
egg_buffer_init (EggBuffer *buffer, size_t reserve)
{
return egg_buffer_init_full (buffer, reserve, NULL);
}
int
egg_buffer_init_full (EggBuffer *buffer, size_t reserve, EggBufferAllocator allocator)
{
memset (buffer, 0, sizeof (*buffer));
if (!allocator)
allocator = DEFAULT_ALLOCATOR;
if (reserve == 0)
reserve = 64;
buffer->buf = (allocator) (NULL, reserve);
if (!buffer->buf) {
buffer->failures++;
return 0;
}
buffer->len = 0;
buffer->allocated_len = reserve;
buffer->failures = 0;
buffer->allocator = allocator;
return 1;
}
void
egg_buffer_init_static (EggBuffer* buffer, const unsigned char *buf, size_t len)
{
memset (buffer, 0, sizeof (*buffer));
buffer->buf = (unsigned char*)buf;
buffer->len = len;
buffer->allocated_len = len;
buffer->failures = 0;
/* A null allocator, and the buffer can't change in size */
buffer->allocator = NULL;
}
void
egg_buffer_init_allocated (EggBuffer *buffer, unsigned char *buf, size_t len,
EggBufferAllocator allocator)
{
memset (buffer, 0, sizeof (*buffer));
if (!allocator)
allocator = DEFAULT_ALLOCATOR;
buffer->buf = buf;
buffer->len = len;
buffer->allocated_len = len;
buffer->failures = 0;
buffer->allocator = allocator;
}
void
egg_buffer_reset (EggBuffer *buffer)
{
memset (buffer->buf, 0, buffer->allocated_len);
buffer->len = 0;
buffer->failures = 0;
}
void
egg_buffer_uninit (EggBuffer *buffer)
{
if (!buffer)
return;
/*
* Free the memory block using allocator. If no allocator,
* then this memory is ownerd elsewhere and not to be freed.
*/
if (buffer->buf && buffer->allocator)
(buffer->allocator) (buffer->buf, 0);
memset (buffer, 0, sizeof (*buffer));
}
unsigned char*
egg_buffer_uninit_steal (EggBuffer *buffer, size_t *n_result)
{
unsigned char *result;
if (n_result)
*n_result = buffer->len;
result = buffer->buf;
memset (buffer, 0, sizeof (*buffer));
return result;
}
int
egg_buffer_set_allocator (EggBuffer *buffer, EggBufferAllocator allocator)
{
unsigned char *buf = NULL;
if (!allocator)
allocator = DEFAULT_ALLOCATOR;
if (buffer->allocator == allocator)
return 1;
if (buffer->allocated_len) {
/* Reallocate memory block using new allocator */
buf = (allocator) (NULL, buffer->allocated_len);
if (buf == NULL)
return 0;
/* Copy stuff into new memory */
memcpy (buf, buffer->buf, buffer->allocated_len);
}
/* If old wasn't static, then free it */
if (buffer->allocator && buffer->buf)
(buffer->allocator) (buffer->buf, 0);
buffer->buf = buf;
buffer->allocator = allocator;
return 1;
}
int
egg_buffer_equal (EggBuffer *b1, EggBuffer *b2)
{
if (b1->len != b2->len)
return 0;
return memcmp (b1->buf, b2->buf, b1->len) == 0;
}
int
egg_buffer_reserve (EggBuffer *buffer, size_t len)
{
unsigned char *newbuf;
size_t newlen;
if (len < buffer->allocated_len)
return 1;
/* Calculate a new length, minimize number of buffer allocations */
newlen = buffer->allocated_len * 2;
if (len > newlen)
newlen += len;
/* Memory owned elsewhere can't be reallocated */
if (!buffer->allocator) {
buffer->failures++;
return 0;
}
/* Reallocate built in buffer using allocator */
newbuf = (buffer->allocator) (buffer->buf, newlen);
if (!newbuf) {
buffer->failures++;
return 0;
}
buffer->buf = newbuf;
buffer->allocated_len = newlen;
return 1;
}
int
egg_buffer_resize (EggBuffer *buffer, size_t len)
{
if (!egg_buffer_reserve (buffer, len))
return 0;
buffer->len = len;
return 1;
}
unsigned char*
egg_buffer_add_empty (EggBuffer *buffer, size_t len)
{
size_t pos = buffer->len;
if (!egg_buffer_reserve (buffer, buffer->len + len))
return NULL;
buffer->len += len;
return buffer->buf + pos;
}
int
egg_buffer_append (EggBuffer *buffer, const unsigned char *val,
size_t len)
{
if (!egg_buffer_reserve (buffer, buffer->len + len))
return 0; /* failures already incremented */
memcpy (buffer->buf + buffer->len, val, len);
buffer->len += len;
return 1;
}
int
egg_buffer_add_byte (EggBuffer *buffer, unsigned char val)
{
if (!egg_buffer_reserve (buffer, buffer->len + 1))
return 0; /* failures already incremented */
buffer->buf[buffer->len] = val;
buffer->len++;
return 1;
}
int
egg_buffer_get_byte (EggBuffer *buffer, size_t offset,
size_t *next_offset, unsigned char *val)
{
unsigned char *ptr;
if (buffer->len < 1 || offset > buffer->len - 1) {
buffer->failures++;
return 0;
}
ptr = (unsigned char*)buffer->buf + offset;
if (val != NULL)
*val = *ptr;
if (next_offset != NULL)
*next_offset = offset + 1;
return 1;
}
void
egg_buffer_encode_uint16 (unsigned char* buf, uint16_t val)
{
buf[0] = (val >> 8) & 0xff;
buf[1] = (val >> 0) & 0xff;
}
uint16_t
egg_buffer_decode_uint16 (unsigned char* buf)
{
uint16_t val = buf[0] << 8 | buf[1];
return val;
}
int
egg_buffer_add_uint16 (EggBuffer *buffer, uint16_t val)
{
if (!egg_buffer_reserve (buffer, buffer->len + 2))
return 0; /* failures already incremented */
buffer->len += 2;
egg_buffer_set_uint16 (buffer, buffer->len - 2, val);
return 1;
}
int
egg_buffer_set_uint16 (EggBuffer *buffer, size_t offset, uint16_t val)
{
unsigned char *ptr;
if (buffer->len < 2 || offset > buffer->len - 2) {
buffer->failures++;
return 0;
}
ptr = (unsigned char*)buffer->buf + offset;
egg_buffer_encode_uint16 (ptr, val);
return 1;
}
int
egg_buffer_get_uint16 (EggBuffer *buffer, size_t offset,
size_t *next_offset, uint16_t *val)
{
unsigned char *ptr;
if (buffer->len < 2 || offset > buffer->len - 2) {
buffer->failures++;
return 0;
}
ptr = (unsigned char*)buffer->buf + offset;
if (val != NULL)
*val = egg_buffer_decode_uint16 (ptr);
if (next_offset != NULL)
*next_offset = offset + 2;
return 1;
}
void
egg_buffer_encode_uint32 (unsigned char* buf, uint32_t val)
{
buf[0] = (val >> 24) & 0xff;
buf[1] = (val >> 16) & 0xff;
buf[2] = (val >> 8) & 0xff;
buf[3] = (val >> 0) & 0xff;
}
uint32_t
egg_buffer_decode_uint32 (unsigned char* ptr)
{
uint32_t val = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
return val;
}
int
egg_buffer_add_uint32 (EggBuffer *buffer, uint32_t val)
{
if (!egg_buffer_reserve (buffer, buffer->len + 4))
return 0; /* failures already incremented */
buffer->len += 4;
egg_buffer_set_uint32 (buffer, buffer->len - 4, val);
return 1;
}
int
egg_buffer_set_uint32 (EggBuffer *buffer, size_t offset, uint32_t val)
{
unsigned char *ptr;
if (buffer->len < 4 || offset > buffer->len - 4) {
buffer->failures++;
return 0;
}
ptr = (unsigned char*)buffer->buf + offset;
egg_buffer_encode_uint32 (ptr, val);
return 1;
}
int
egg_buffer_get_uint32 (EggBuffer *buffer, size_t offset, size_t *next_offset,
uint32_t *val)
{
unsigned char *ptr;
if (buffer->len < 4 || offset > buffer->len - 4) {
buffer->failures++;
return 0;
}
ptr = (unsigned char*)buffer->buf + offset;
if (val != NULL)
*val = egg_buffer_decode_uint32 (ptr);
if (next_offset != NULL)
*next_offset = offset + 4;
return 1;
}
int
egg_buffer_add_uint64 (EggBuffer *buffer, uint64_t val)
{
if (!egg_buffer_add_uint32 (buffer, ((val >> 32) & 0xffffffff)))
return 0;
return egg_buffer_add_uint32 (buffer, (val & 0xffffffff));
}
int
egg_buffer_get_uint64 (EggBuffer *buffer, size_t offset,
size_t *next_offset, uint64_t *val)
{
uint32_t a, b;
if (!egg_buffer_get_uint32 (buffer, offset, &offset, &a))
return 0;
if (!egg_buffer_get_uint32 (buffer, offset, &offset, &b))
return 0;
if (val != NULL)
*val = ((uint64_t)a) << 32 | b;
if (next_offset != NULL)
*next_offset = offset;
return 1;
}
int
egg_buffer_add_byte_array (EggBuffer *buffer, const unsigned char *val,
size_t len)
{
if (val == NULL)
return egg_buffer_add_uint32 (buffer, 0xffffffff);
if (len >= 0x7fffffff) {
buffer->failures++;
return 0;
}
if (!egg_buffer_add_uint32 (buffer, len))
return 0;
return egg_buffer_append (buffer, val, len);
}
unsigned char*
egg_buffer_add_byte_array_empty (EggBuffer *buffer, size_t vlen)
{
if (vlen >= 0x7fffffff) {
buffer->failures++;
return NULL;
}
if (!egg_buffer_add_uint32 (buffer, vlen))
return NULL;
return egg_buffer_add_empty (buffer, vlen);
}
int
egg_buffer_get_byte_array (EggBuffer *buffer, size_t offset,
size_t *next_offset, const unsigned char **val,
size_t *vlen)
{
uint32_t len;
if (!egg_buffer_get_uint32 (buffer, offset, &offset, &len))
return 0;
if (len == 0xffffffff) {
if (next_offset)
*next_offset = offset;
if (val)
*val = NULL;
if (vlen)
*vlen = 0;
return 1;
} else if (len >= 0x7fffffff) {
buffer->failures++;
return 0;
}
if (buffer->len < len || offset > buffer->len - len) {
buffer->failures++;
return 0;
}
if (val)
*val = buffer->buf + offset;
if (vlen)
*vlen = len;
if (next_offset)
*next_offset = offset + len;
return 1;
}
int
egg_buffer_add_string (EggBuffer *buffer, const char *str)
{
if (str == NULL) {
return egg_buffer_add_uint32 (buffer, 0xffffffff);
} else {
size_t len = strlen (str);
if (len >= 0x7fffffff)
return 0;
if (!egg_buffer_add_uint32 (buffer, len))
return 0;
return egg_buffer_append (buffer, (unsigned char*)str, len);
}
}
int
egg_buffer_get_string (EggBuffer *buffer, size_t offset, size_t *next_offset,
char **str_ret, EggBufferAllocator allocator)
{
uint32_t len;
if (!allocator)
allocator = buffer->allocator;
if (!allocator)
allocator = DEFAULT_ALLOCATOR;
if (!egg_buffer_get_uint32 (buffer, offset, &offset, &len)) {
return 0;
}
if (len == 0xffffffff) {
*next_offset = offset;
*str_ret = NULL;
return 1;
} else if (len >= 0x7fffffff) {
return 0;
}
if (buffer->len < len ||
offset > buffer->len - len) {
return 0;
}
/* Make sure no null characters in string */
if (memchr (buffer->buf + offset, 0, len) != NULL)
return 0;
/* The passed allocator may be for non-pageable memory */
*str_ret = (allocator) (NULL, len + 1);
if (!*str_ret)
return 0;
memcpy (*str_ret, buffer->buf + offset, len);
/* Always zero terminate */
(*str_ret)[len] = 0;
*next_offset = offset + len;
return 1;
}
int
egg_buffer_add_stringv (EggBuffer *buffer, const char** strv)
{
const char **v;
uint32_t n = 0;
if (!strv)
return 0;
/* Add the number of strings coming */
for (v = strv; *v; ++v)
++n;
if (!egg_buffer_add_uint32 (buffer, n))
return 0;
/* Add the individual strings */
for (v = strv; *v; ++v) {
if (!egg_buffer_add_string (buffer, *v))
return 0;
}
return 1;
}
int
egg_buffer_get_stringv (EggBuffer *buffer, size_t offset, size_t *next_offset,
char ***strv_ret, EggBufferAllocator allocator)
{
uint32_t n, i, j;
size_t len;
if (!allocator)
allocator = buffer->allocator;
if (!allocator)
allocator = DEFAULT_ALLOCATOR;
/* First the number of environment variable lines */
if (!egg_buffer_get_uint32 (buffer, offset, &offset, &n))
return 0;
/* Then that number of strings */
len = (n + 1) * sizeof (char*);
*strv_ret = (char**)(allocator) (NULL, len);
if (!*strv_ret)
return 0;
/* All null strings */
memset (*strv_ret, 0, len);
for (i = 0; i < n; ++i) {
if (!egg_buffer_get_string (buffer, offset, &offset,
&((*strv_ret)[i]), allocator)) {
/* Free all the strings on failure */
for (j = 0; j < i; ++j) {
if ((*strv_ret)[j])
(allocator) ((*strv_ret)[j], 0);
}
return 0;
}
}
if (next_offset != NULL)
*next_offset = offset;
return 1;
}