/*
* Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <errno.h>
#include "bio_local.h"
#include "internal/cryptlib.h"
static int mem_write(BIO *h, const char *buf, int num);
static int mem_read(BIO *h, char *buf, int size);
static int mem_puts(BIO *h, const char *str);
static int mem_gets(BIO *h, char *str, int size);
static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);
static int mem_new(BIO *h);
static int secmem_new(BIO *h);
static int mem_free(BIO *data);
static int mem_buf_free(BIO *data);
static int mem_buf_sync(BIO *h);
static const BIO_METHOD mem_method = {
BIO_TYPE_MEM,
"memory buffer",
/* TODO: Convert to new style write function */
bwrite_conv,
mem_write,
/* TODO: Convert to new style read function */
bread_conv,
mem_read,
mem_puts,
mem_gets,
mem_ctrl,
mem_new,
mem_free,
NULL, /* mem_callback_ctrl */
};
static const BIO_METHOD secmem_method = {
BIO_TYPE_MEM,
"secure memory buffer",
/* TODO: Convert to new style write function */
bwrite_conv,
mem_write,
/* TODO: Convert to new style read function */
bread_conv,
mem_read,
mem_puts,
mem_gets,
mem_ctrl,
secmem_new,
mem_free,
NULL, /* mem_callback_ctrl */
};
/*
* BIO memory stores buffer and read pointer
* however the roles are different for read only BIOs.
* In that case the readp just stores the original state
* to be used for reset.
*/
typedef struct bio_buf_mem_st {
struct buf_mem_st *buf; /* allocated buffer */
struct buf_mem_st *readp; /* read pointer */
} BIO_BUF_MEM;
/*
* bio->num is used to hold the value to return on 'empty', if it is 0,
* should_retry is not set
*/
const BIO_METHOD *BIO_s_mem(void)
{
return &mem_method;
}
const BIO_METHOD *BIO_s_secmem(void)
{
return(&secmem_method);
}
BIO *BIO_new_mem_buf(const void *buf, int len)
{
BIO *ret;
BUF_MEM *b;
BIO_BUF_MEM *bb;
size_t sz;
if (buf == NULL) {
BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER);
return NULL;
}
sz = (len < 0) ? strlen(buf) : (size_t)len;
if ((ret = BIO_new(BIO_s_mem())) == NULL)
return NULL;
bb = (BIO_BUF_MEM *)ret->ptr;
b = bb->buf;
/* Cast away const and trust in the MEM_RDONLY flag. */
b->data = (void *)buf;
b->length = sz;
b->max = sz;
*bb->readp = *bb->buf;
ret->flags |= BIO_FLAGS_MEM_RDONLY;
/* Since this is static data retrying won't help */
ret->num = 0;
return ret;
}
static int mem_init(BIO *bi, unsigned long flags)
{
BIO_BUF_MEM *bb = OPENSSL_zalloc(sizeof(*bb));
if (bb == NULL)
return 0;
if ((bb->buf = BUF_MEM_new_ex(flags)) == NULL) {
OPENSSL_free(bb);
return 0;
}
if ((bb->readp = OPENSSL_zalloc(sizeof(*bb->readp))) == NULL) {
BUF_MEM_free(bb->buf);
OPENSSL_free(bb);
return 0;
}
*bb->readp = *bb->buf;
bi->shutdown = 1;
bi->init = 1;
bi->num = -1;
bi->ptr = (char *)bb;
return 1;
}
static int mem_new(BIO *bi)
{
return mem_init(bi, 0L);
}
static int secmem_new(BIO *bi)
{
return mem_init(bi, BUF_MEM_FLAG_SECURE);
}
static int mem_free(BIO *a)
{
BIO_BUF_MEM *bb;
if (a == NULL)
return 0;
bb = (BIO_BUF_MEM *)a->ptr;
if (!mem_buf_free(a))
return 0;
OPENSSL_free(bb->readp);
OPENSSL_free(bb);
return 1;
}
static int mem_buf_free(BIO *a)
{
if (a == NULL)
return 0;
if (a->shutdown && a->init && a->ptr != NULL) {
BIO_BUF_MEM *bb = (BIO_BUF_MEM *)a->ptr;
BUF_MEM *b = bb->buf;
if (a->flags & BIO_FLAGS_MEM_RDONLY)
b->data = NULL;
BUF_MEM_free(b);
}
return 1;
}
/*
* Reallocate memory buffer if read pointer differs
*/
static int mem_buf_sync(BIO *b)
{
if (b != NULL && b->init != 0 && b->ptr != NULL) {
BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
if (bbm->readp->data != bbm->buf->data) {
memmove(bbm->buf->data, bbm->readp->data, bbm->readp->length);
bbm->buf->length = bbm->readp->length;
bbm->readp->data = bbm->buf->data;
}
}
return 0;
}
static int mem_read(BIO *b, char *out, int outl)
{
int ret = -1;
BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
BUF_MEM *bm = bbm->readp;
if (b->flags & BIO_FLAGS_MEM_RDONLY)
bm = bbm->buf;
BIO_clear_retry_flags(b);
ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
if ((out != NULL) && (ret > 0)) {
memcpy(out, bm->data, ret);
bm->length -= ret;
bm->max -= ret;
bm->data += ret;
} else if (bm->length == 0) {
ret = b->num;
if (ret != 0)
BIO_set_retry_read(b);
}
return ret;
}
static int mem_write(BIO *b, const char *in, int inl)
{
int ret = -1;
int blen;
BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
if (in == NULL) {
BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);
goto end;
}
if (b->flags & BIO_FLAGS_MEM_RDONLY) {
BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);
goto end;
}
BIO_clear_retry_flags(b);
if (inl == 0)
return 0;
blen = bbm->readp->length;
mem_buf_sync(b);
if (BUF_MEM_grow_clean(bbm->buf, blen + inl) == 0)
goto end;
memcpy(bbm->buf->data + blen, in, inl);
*bbm->readp = *bbm->buf;
ret = inl;
end:
return ret;
}
static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
{
long ret = 1;
char **pptr;
BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
BUF_MEM *bm;
if (b->flags & BIO_FLAGS_MEM_RDONLY)
bm = bbm->buf;
else
bm = bbm->readp;
switch (cmd) {
case BIO_CTRL_RESET:
bm = bbm->buf;
if (bm->data != NULL) {
if (!(b->flags & BIO_FLAGS_MEM_RDONLY)) {
if (!(b->flags & BIO_FLAGS_NONCLEAR_RST)) {
memset(bm->data, 0, bm->max);
bm->length = 0;
}
*bbm->readp = *bbm->buf;
} else {
/* For read only case just reset to the start again */
*bbm->buf = *bbm->readp;
}
}
break;
case BIO_CTRL_EOF:
ret = (long)(bm->length == 0);
break;
case BIO_C_SET_BUF_MEM_EOF_RETURN:
b->num = (int)num;
break;
case BIO_CTRL_INFO:
ret = (long)bm->length;
if (ptr != NULL) {
pptr = (char **)ptr;
*pptr = (char *)bm->data;
}
break;
case BIO_C_SET_BUF_MEM:
mem_buf_free(b);
b->shutdown = (int)num;
bbm->buf = ptr;
*bbm->readp = *bbm->buf;
break;
case BIO_C_GET_BUF_MEM_PTR:
if (ptr != NULL) {
if (!(b->flags & BIO_FLAGS_MEM_RDONLY))
mem_buf_sync(b);
bm = bbm->buf;
pptr = (char **)ptr;
*pptr = (char *)bm;
}
break;
case BIO_CTRL_GET_CLOSE:
ret = (long)b->shutdown;
break;
case BIO_CTRL_SET_CLOSE:
b->shutdown = (int)num;
break;
case BIO_CTRL_WPENDING:
ret = 0L;
break;
case BIO_CTRL_PENDING:
ret = (long)bm->length;
break;
case BIO_CTRL_DUP:
case BIO_CTRL_FLUSH:
ret = 1;
break;
case BIO_CTRL_PUSH:
case BIO_CTRL_POP:
default:
ret = 0;
break;
}
return ret;
}
static int mem_gets(BIO *bp, char *buf, int size)
{
int i, j;
int ret = -1;
char *p;
BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)bp->ptr;
BUF_MEM *bm = bbm->readp;
if (bp->flags & BIO_FLAGS_MEM_RDONLY)
bm = bbm->buf;
BIO_clear_retry_flags(bp);
j = bm->length;
if ((size - 1) < j)
j = size - 1;
if (j <= 0) {
*buf = '\0';
return 0;
}
p = bm->data;
for (i = 0; i < j; i++) {
if (p[i] == '\n') {
i++;
break;
}
}
/*
* i is now the max num of bytes to copy, either j or up to
* and including the first newline
*/
i = mem_read(bp, buf, i);
if (i > 0)
buf[i] = '\0';
ret = i;
return ret;
}
static int mem_puts(BIO *bp, const char *str)
{
int n, ret;
n = strlen(str);
ret = mem_write(bp, str, n);
/* memory semantics is that it will always work */
return ret;
}
