diff options
Diffstat (limited to 'third_party/heimdal/lib/krb5/store_emem.c')
| -rw-r--r-- | third_party/heimdal/lib/krb5/store_emem.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/krb5/store_emem.c b/third_party/heimdal/lib/krb5/store_emem.c new file mode 100644 index 0000000..daef4d7 --- /dev/null +++ b/third_party/heimdal/lib/krb5/store_emem.c @@ -0,0 +1,222 @@ +/* + * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * 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. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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. + */ + +#include "krb5_locl.h" +#include "store-int.h" +#include <assert.h> + +typedef struct emem_storage{ + unsigned char *base; + size_t size; + size_t len; + unsigned char *ptr; +}emem_storage; + +static ssize_t +emem_fetch(krb5_storage *sp, void *data, size_t size) +{ + emem_storage *s = (emem_storage*)sp->data; + + assert(data != NULL && s->ptr != NULL); + + if((size_t)(s->base + s->len - s->ptr) < size) + size = s->base + s->len - s->ptr; + memmove(data, s->ptr, size); + sp->seek(sp, size, SEEK_CUR); + return size; +} + +static ssize_t +emem_store(krb5_storage *sp, const void *data, size_t size) +{ + emem_storage *s; + + if (size == 0) { + sp->seek(sp, 0, SEEK_CUR); + return 0; + } + + s = (emem_storage*)sp->data; + + assert(data != NULL); + + if(size > (size_t)(s->base + s->size - s->ptr)){ + void *base; + size_t sz, off; + off = s->ptr - s->base; + sz = off + size; + if (sz < 4096) + sz *= 2; + base = realloc(s->base, sz); + if(base == NULL) + return -1; + s->size = sz; + s->base = base; + s->ptr = (unsigned char*)base + off; + } + if (size) + memmove(s->ptr, data, size); + sp->seek(sp, size, SEEK_CUR); + return size; +} + +static off_t +emem_seek(krb5_storage *sp, off_t offset, int whence) +{ + emem_storage *s = (emem_storage*)sp->data; + switch(whence){ + case SEEK_SET: + if((size_t)offset > s->size) + offset = s->size; + if(offset < 0) + offset = 0; + s->ptr = s->base + offset; + if((size_t)offset > s->len) + s->len = offset; + break; + case SEEK_CUR: + sp->seek(sp,s->ptr - s->base + offset, SEEK_SET); + break; + case SEEK_END: + sp->seek(sp, s->len + offset, SEEK_SET); + break; + default: + errno = EINVAL; + return -1; + } + return s->ptr - s->base; +} + +static int +emem_trunc(krb5_storage *sp, off_t offset) +{ + emem_storage *s = (emem_storage*)sp->data; + /* + * If offset is larget then current size, or current size is + * shrunk more then half of the current size, adjust buffer. + */ + if (offset == 0) { + if (s->size > 1024) { + void *base; + + base = realloc(s->base, 1024); + if (base) { + s->base = base; + s->size = 1024; + } + } + s->len = 0; + s->ptr = s->base; + } else if ((size_t)offset > s->size || (s->size / 2) > (size_t)offset) { + void *base; + size_t off; + off = s->ptr - s->base; + base = realloc(s->base, offset); + if(base == NULL) + return ENOMEM; + if ((size_t)offset > s->size) + memset((char *)base + s->size, 0, offset - s->size); + s->size = offset; + s->base = base; + s->ptr = (unsigned char *)base + off; + } + s->len = offset; + if ((s->ptr - s->base) > offset) + s->ptr = s->base + offset; + return 0; +} + + +static void +emem_free(krb5_storage *sp) +{ + emem_storage *s = sp->data; + + assert(s->base != NULL); + + memset_s(s->base, s->len, 0, s->len); + free(s->base); +} + +/** + * Create a elastic (allocating) memory storage backend. Memory is + * allocated on demand. Free returned krb5_storage with + * krb5_storage_free(). + * + * @return A krb5_storage on success, or NULL on out of memory error. + * + * @ingroup krb5_storage + * + * @sa krb5_storage_from_mem() + * @sa krb5_storage_from_readonly_mem() + * @sa krb5_storage_from_fd() + * @sa krb5_storage_from_data() + * @sa krb5_storage_from_socket() + */ + +KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL +krb5_storage_emem(void) +{ + krb5_storage *sp; + emem_storage *s; + + sp = malloc(sizeof(krb5_storage)); + if (sp == NULL) + return NULL; + + s = malloc(sizeof(*s)); + if (s == NULL) { + free(sp); + return NULL; + } + sp->data = s; + sp->flags = 0; + sp->eof_code = HEIM_ERR_EOF; + s->size = 1024; + s->base = calloc(1, s->size); + if (s->base == NULL) { + free(sp); + free(s); + return NULL; + } + s->len = 0; + s->ptr = s->base; + sp->fetch = emem_fetch; + sp->store = emem_store; + sp->seek = emem_seek; + sp->trunc = emem_trunc; + sp->fsync = NULL; + sp->free = emem_free; + sp->max_alloc = UINT32_MAX/64; + return sp; +} |