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-rw-r--r--lib/libarchive/archive_read.c601
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diff --git a/lib/libarchive/archive_read.c b/lib/libarchive/archive_read.c
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+++ b/lib/libarchive/archive_read.c
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+/*-
+ * Copyright (c) 2003-2004 Tim Kientzle
+ * 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
+ * in this position and unchanged.
+ * 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 AUTHOR(S) ``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 AUTHOR(S) 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.
+ */
+
+/*
+ * This file contains the "essential" portions of the read API, that
+ * is, stuff that will probably always be used by any client that
+ * actually needs to read an archive. Optional pieces have been, as
+ * far as possible, separated out into separate files to avoid
+ * needlessly bloating statically-linked clients.
+ */
+
+#include "archive_platform.h"
+__FBSDID("$FreeBSD$");
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "archive.h"
+#include "archive_entry.h"
+#include "archive_private.h"
+
+static int choose_decompressor(struct archive *, const void*, size_t);
+static int choose_format(struct archive *);
+
+/*
+ * Allocate, initialize and return a struct archive object.
+ */
+struct archive *
+archive_read_new(void)
+{
+ struct archive *a;
+ unsigned char *nulls;
+
+ a = malloc(sizeof(*a));
+ if (a == NULL) {
+ archive_set_error(a, ENOMEM, "Can't allocate archive object");
+ return (NULL);
+ }
+ memset(a, 0, sizeof(*a));
+
+ a->user_uid = geteuid();
+ a->magic = ARCHIVE_READ_MAGIC;
+ a->bytes_per_block = ARCHIVE_DEFAULT_BYTES_PER_BLOCK;
+
+ a->null_length = 1024;
+ nulls = malloc(a->null_length);
+ if (nulls == NULL) {
+ archive_set_error(a, ENOMEM, "Can't allocate archive object 'nulls' element");
+ free(a);
+ return (NULL);
+ }
+ memset(nulls, 0, a->null_length);
+ a->nulls = nulls;
+
+ a->state = ARCHIVE_STATE_NEW;
+ a->entry = archive_entry_new();
+
+ /* We always support uncompressed archives. */
+ archive_read_support_compression_none((struct archive*)a);
+
+ return (a);
+}
+
+/*
+ * Set the block size.
+ */
+/*
+int
+archive_read_set_bytes_per_block(struct archive *a, int bytes_per_block)
+{
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW, "archive_read_set_bytes_per_block");
+ if (bytes_per_block < 1)
+ bytes_per_block = 1;
+ a->bytes_per_block = bytes_per_block;
+ return (0);
+}
+*/
+
+/*
+ * Open the archive
+ */
+int
+archive_read_open(struct archive *a, void *client_data,
+ archive_open_callback *client_opener, archive_read_callback *client_reader,
+ archive_close_callback *client_closer)
+{
+ const void *buffer;
+ ssize_t bytes_read;
+ int high_bidder;
+ int e;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW, "archive_read_open");
+
+ if (client_reader == NULL)
+ __archive_errx(1,
+ "No reader function provided to archive_read_open");
+
+ /*
+ * Set these NULL initially. If the open or initial read fails,
+ * we'll leave them NULL to indicate that the file is invalid.
+ * (In particular, this helps ensure that the closer doesn't
+ * get called more than once.)
+ */
+ a->client_opener = NULL;
+ a->client_reader = NULL;
+ a->client_closer = NULL;
+ a->client_data = NULL;
+
+ /* Open data source. */
+ if (client_opener != NULL) {
+ e =(client_opener)(a, client_data);
+ if (e != 0) {
+ /* If the open failed, call the closer to clean up. */
+ if (client_closer)
+ (client_closer)(a, client_data);
+ return (e);
+ }
+ }
+
+ /* Read first block now for format detection. */
+ bytes_read = (client_reader)(a, client_data, &buffer);
+
+ if (bytes_read < 0) {
+ /* If the first read fails, close before returning error. */
+ if (client_closer)
+ (client_closer)(a, client_data);
+ /* client_reader should have already set error information. */
+ return (ARCHIVE_FATAL);
+ }
+
+ /* An empty archive is a serious error. */
+ if (bytes_read == 0) {
+ archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
+ "Empty input file");
+ /* Close the empty file. */
+ if (client_closer)
+ (client_closer)(a, client_data);
+ return (ARCHIVE_FATAL);
+ }
+
+ /* Now that the client callbacks have worked, remember them. */
+ a->client_opener = client_opener; /* Do we need to remember this? */
+ a->client_reader = client_reader;
+ a->client_closer = client_closer;
+ a->client_data = client_data;
+
+ /* Select a decompression routine. */
+ high_bidder = choose_decompressor(a, buffer, bytes_read);
+ if (high_bidder < 0)
+ return (ARCHIVE_FATAL);
+
+ /* Initialize decompression routine with the first block of data. */
+ e = (a->decompressors[high_bidder].init)(a, buffer, bytes_read);
+
+ if (e == ARCHIVE_OK)
+ a->state = ARCHIVE_STATE_HEADER;
+
+ return (e);
+}
+
+/*
+ * Allow each registered decompression routine to bid on whether it
+ * wants to handle this stream. Return index of winning bidder.
+ */
+static int
+choose_decompressor(struct archive *a, const void *buffer, size_t bytes_read)
+{
+ int decompression_slots, i, bid, best_bid, best_bid_slot;
+
+ decompression_slots = sizeof(a->decompressors) /
+ sizeof(a->decompressors[0]);
+
+ best_bid = -1;
+ best_bid_slot = -1;
+
+ for (i = 0; i < decompression_slots; i++) {
+ if (a->decompressors[i].bid) {
+ bid = (a->decompressors[i].bid)(buffer, bytes_read);
+ if ((bid > best_bid) || (best_bid_slot < 0)) {
+ best_bid = bid;
+ best_bid_slot = i;
+ }
+ }
+ }
+
+ /*
+ * There were no bidders; this is a serious programmer error
+ * and demands a quick and definitive abort.
+ */
+ if (best_bid_slot < 0)
+ __archive_errx(1, "No decompressors were registered; you "
+ "must call at least one "
+ "archive_read_support_compression_XXX function in order "
+ "to successfully read an archive.");
+
+ /*
+ * There were bidders, but no non-zero bids; this means we can't
+ * support this stream.
+ */
+ if (best_bid < 1) {
+ archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
+ "Unrecognized archive format");
+ return (ARCHIVE_FATAL);
+ }
+
+ return (best_bid_slot);
+}
+
+/*
+ * Read header of next entry.
+ */
+int
+archive_read_next_header(struct archive *a, struct archive_entry **entryp)
+{
+ struct archive_entry *entry;
+ int slot, ret;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC,
+ ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA, "archive_read_next_header");
+
+ *entryp = NULL;
+ entry = a->entry;
+ archive_entry_clear(entry);
+ archive_string_empty(&a->error_string);
+
+ /*
+ * If client didn't consume entire data, skip any remainder
+ * (This is especially important for GNU incremental directories.)
+ */
+ if (a->state == ARCHIVE_STATE_DATA) {
+ ret = archive_read_data_skip(a);
+ if (ret == ARCHIVE_EOF) {
+ archive_set_error(a, EIO, "Premature end-of-file.");
+ a->state = ARCHIVE_STATE_FATAL;
+ return (ARCHIVE_FATAL);
+ }
+ if (ret != ARCHIVE_OK)
+ return (ret);
+ }
+
+ /* Record start-of-header. */
+ a->header_position = a->file_position;
+
+ slot = choose_format(a);
+ if (slot < 0) {
+ a->state = ARCHIVE_STATE_FATAL;
+ return (ARCHIVE_FATAL);
+ }
+ a->format = &(a->formats[slot]);
+ a->pformat_data = &(a->format->format_data);
+ ret = (a->format->read_header)(a, entry);
+
+ /*
+ * EOF and FATAL are persistent at this layer. By
+ * modifying the state, we gaurantee that future calls to
+ * read a header or read data will fail.
+ */
+ switch (ret) {
+ case ARCHIVE_EOF:
+ a->state = ARCHIVE_STATE_EOF;
+ break;
+ case ARCHIVE_OK:
+ a->state = ARCHIVE_STATE_DATA;
+ break;
+ case ARCHIVE_WARN:
+ a->state = ARCHIVE_STATE_DATA;
+ break;
+ case ARCHIVE_RETRY:
+ break;
+ case ARCHIVE_FATAL:
+ a->state = ARCHIVE_STATE_FATAL;
+ break;
+ }
+
+ *entryp = entry;
+ a->read_data_output_offset = 0;
+ a->read_data_remaining = 0;
+ return (ret);
+}
+
+/*
+ * Allow each registered format to bid on whether it wants to handle
+ * the next entry. Return index of winning bidder.
+ */
+static int
+choose_format(struct archive *a)
+{
+ int slots;
+ int i;
+ int bid, best_bid;
+ int best_bid_slot;
+
+ slots = sizeof(a->formats) / sizeof(a->formats[0]);
+ best_bid = -1;
+ best_bid_slot = -1;
+
+ /* Set up a->format and a->pformat_data for convenience of bidders. */
+ a->format = &(a->formats[0]);
+ for (i = 0; i < slots; i++, a->format++) {
+ if (a->format->bid) {
+ a->pformat_data = &(a->format->format_data);
+ bid = (a->format->bid)(a);
+ if (bid == ARCHIVE_FATAL)
+ return (ARCHIVE_FATAL);
+ if ((bid > best_bid) || (best_bid_slot < 0)) {
+ best_bid = bid;
+ best_bid_slot = i;
+ }
+ }
+ }
+
+ /*
+ * There were no bidders; this is a serious programmer error
+ * and demands a quick and definitive abort.
+ */
+ if (best_bid_slot < 0)
+ __archive_errx(1, "No formats were registered; you must "
+ "invoke at least one archive_read_support_format_XXX "
+ "function in order to successfully read an archive.");
+
+ /*
+ * There were bidders, but no non-zero bids; this means we
+ * can't support this stream.
+ */
+ if (best_bid < 1) {
+ archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
+ "Unrecognized archive format");
+ return (ARCHIVE_FATAL);
+ }
+
+ return (best_bid_slot);
+}
+
+/*
+ * Return the file offset (within the uncompressed data stream) where
+ * the last header started.
+ */
+int64_t
+archive_read_header_position(struct archive *a)
+{
+ return (a->header_position);
+}
+
+/*
+ * Read data from an archive entry, using a read(2)-style interface.
+ * This is a convenience routine that just calls
+ * archive_read_data_block and copies the results into the client
+ * buffer, filling any gaps with zero bytes. Clients using this
+ * API can be completely ignorant of sparse-file issues; sparse files
+ * will simply be padded with nulls.
+ *
+ * DO NOT intermingle calls to this function and archive_read_data_block
+ * to read a single entry body.
+ */
+ssize_t
+archive_read_data(struct archive *a, void *buff, size_t s)
+{
+ char *dest;
+ size_t bytes_read;
+ size_t len;
+ int r;
+
+ bytes_read = 0;
+ dest = buff;
+
+ while (s > 0) {
+ if (a->read_data_remaining <= 0) {
+ r = archive_read_data_block(a,
+ (const void **)&a->read_data_block,
+ &a->read_data_remaining,
+ &a->read_data_offset);
+ if (r == ARCHIVE_EOF)
+ return (bytes_read);
+ /*
+ * Error codes are all negative, so the status
+ * return here cannot be confused with a valid
+ * byte count. (ARCHIVE_OK is zero.)
+ */
+ if (r < ARCHIVE_OK)
+ return (r);
+ }
+
+ if (a->read_data_offset < a->read_data_output_offset) {
+ archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
+ "Encountered out-of-order sparse blocks");
+ return (ARCHIVE_RETRY);
+ } else {
+ len = a->read_data_remaining;
+ if (len > s)
+ len = s;
+ memcpy(dest, a->read_data_block, len);
+ s -= len;
+ a->read_data_block += len;
+ a->read_data_remaining -= len;
+ a->read_data_output_offset += len;
+ a->read_data_offset += len;
+ dest += len;
+ bytes_read += len;
+ }
+ }
+ return (bytes_read);
+}
+
+/*
+ * Skip over all remaining data in this entry.
+ */
+int
+archive_read_data_skip(struct archive *a)
+{
+ int r;
+ const void *buff;
+ size_t size;
+ off_t offset;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_DATA, "archive_read_data_skip");
+
+ if (a->format->read_data_skip != NULL)
+ r = (a->format->read_data_skip)(a);
+ else {
+ while ((r = archive_read_data_block(a, &buff, &size, &offset))
+ == ARCHIVE_OK)
+ ;
+ }
+
+ if (r == ARCHIVE_EOF)
+ r = ARCHIVE_OK;
+
+ a->state = ARCHIVE_STATE_HEADER;
+ return (r);
+}
+
+/*
+ * Read the next block of entry data from the archive.
+ * This is a zero-copy interface; the client receives a pointer,
+ * size, and file offset of the next available block of data.
+ *
+ * Returns ARCHIVE_OK if the operation is successful, ARCHIVE_EOF if
+ * the end of entry is encountered.
+ */
+int
+archive_read_data_block(struct archive *a,
+ const void **buff, size_t *size, off_t *offset)
+{
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_DATA, "archive_read_data_block");
+
+ if (a->format->read_data == NULL) {
+ archive_set_error(a, ARCHIVE_ERRNO_PROGRAMMER,
+ "Internal error: "
+ "No format_read_data_block function registered");
+ return (ARCHIVE_FATAL);
+ }
+
+ return (a->format->read_data)(a, buff, size, offset);
+}
+
+/*
+ * Close the file and release most resources.
+ *
+ * Be careful: client might just call read_new and then read_finish.
+ * Don't assume we actually read anything or performed any non-trivial
+ * initialization.
+ */
+int
+archive_read_close(struct archive *a)
+{
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_ANY, "archive_read_close");
+ a->state = ARCHIVE_STATE_CLOSED;
+
+ /* Call cleanup functions registered by optional components. */
+ if (a->cleanup_archive_extract != NULL)
+ (a->cleanup_archive_extract)(a);
+
+ /* TODO: Finish the format processing. */
+
+ /* Close the input machinery. */
+ if (a->compression_finish != NULL)
+ (a->compression_finish)(a);
+ return (ARCHIVE_OK);
+}
+
+/*
+ * Release memory and other resources.
+ */
+void
+archive_read_finish(struct archive *a)
+{
+ int i;
+ int slots;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_ANY, "archive_read_finish");
+ if (a->state != ARCHIVE_STATE_CLOSED)
+ archive_read_close(a);
+
+ /* Cleanup format-specific data. */
+ slots = sizeof(a->formats) / sizeof(a->formats[0]);
+ for (i = 0; i < slots; i++) {
+ a->pformat_data = &(a->formats[i].format_data);
+ if (a->formats[i].cleanup)
+ (a->formats[i].cleanup)(a);
+ }
+
+ /* Casting a pointer to int allows us to remove 'const.' */
+ free((void *)(uintptr_t)(const void *)a->nulls);
+ archive_string_free(&a->error_string);
+ if (a->entry)
+ archive_entry_free(a->entry);
+ a->magic = 0;
+ free(a);
+}
+
+/*
+ * Used internally by read format handlers to register their bid and
+ * initialization functions.
+ */
+int
+__archive_read_register_format(struct archive *a,
+ void *format_data,
+ int (*bid)(struct archive *),
+ int (*read_header)(struct archive *, struct archive_entry *),
+ int (*read_data)(struct archive *, const void **, size_t *, off_t *),
+ int (*read_data_skip)(struct archive *),
+ int (*cleanup)(struct archive *))
+{
+ int i, number_slots;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW, "__archive_read_register_format");
+
+ number_slots = sizeof(a->formats) / sizeof(a->formats[0]);
+
+ for (i = 0; i < number_slots; i++) {
+ if (a->formats[i].bid == bid)
+ return (ARCHIVE_WARN); /* We've already installed */
+ if (a->formats[i].bid == NULL) {
+ a->formats[i].bid = bid;
+ a->formats[i].read_header = read_header;
+ a->formats[i].read_data = read_data;
+ a->formats[i].read_data_skip = read_data_skip;
+ a->formats[i].cleanup = cleanup;
+ a->formats[i].format_data = format_data;
+ return (ARCHIVE_OK);
+ }
+ }
+
+ __archive_errx(1, "Not enough slots for format registration");
+ return (ARCHIVE_FATAL); /* Never actually called. */
+}
+
+/*
+ * Used internally by decompression routines to register their bid and
+ * initialization functions.
+ */
+int
+__archive_read_register_compression(struct archive *a,
+ int (*bid)(const void *, size_t),
+ int (*init)(struct archive *, const void *, size_t))
+{
+ int i, number_slots;
+
+ __archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW, "__archive_read_register_compression");
+
+ number_slots = sizeof(a->decompressors) / sizeof(a->decompressors[0]);
+
+ for (i = 0; i < number_slots; i++) {
+ if (a->decompressors[i].bid == bid)
+ return (ARCHIVE_OK); /* We've already installed */
+ if (a->decompressors[i].bid == NULL) {
+ a->decompressors[i].bid = bid;
+ a->decompressors[i].init = init;
+ return (ARCHIVE_OK);
+ }
+ }
+
+ __archive_errx(1, "Not enough slots for compression registration");
+ return (ARCHIVE_FATAL); /* Never actually executed. */
+}
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