1 files changed, 0 insertions, 527 deletions

diff --git a/fuse_sideload.c b/fuse_sideload.c
deleted file mode 100644
index 48e6cc53a..000000000
--- a/fuse_sideload.c
+++ /dev/null
@@ -1,527 +0,0 @@
-/*
- * Copyright (C) 2014 The Android Open Source Project
- *
- * 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.
- */
-
-// This module creates a special filesystem containing two files.
-//
-// "/sideload/package.zip" appears to be a normal file, but reading
-// from it causes data to be fetched from the adb host.  We can use
-// this to sideload packages over an adb connection without having to
-// store the entire package in RAM on the device.
-//
-// Because we may not trust the adb host, this filesystem maintains
-// the following invariant: each read of a given position returns the
-// same data as the first read at that position.  That is, once a
-// section of the file is read, future reads of that section return
-// the same data.  (Otherwise, a malicious adb host process could
-// return one set of bits when the package is read for signature
-// verification, and then different bits for when the package is
-// accessed by the installer.)  If the adb host returns something
-// different than it did on the first read, the reader of the file
-// will see their read fail with EINVAL.
-//
-// The other file, "/sideload/exit", is used to control the subprocess
-// that creates this filesystem.  Calling stat() on the exit file
-// causes the filesystem to be unmounted and the adb process on the
-// device shut down.
-//
-// Note that only the minimal set of file operations needed for these
-// two files is implemented.  In particular, you can't opendir() or
-// readdir() on the "/sideload" directory; ls on it won't work.
-
-#include <ctype.h>
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <linux/fuse.h>
-#include <pthread.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/inotify.h>
-#include <sys/mount.h>
-#include <sys/param.h>
-#include <sys/resource.h>
-#include <sys/stat.h>
-#include <sys/statfs.h>
-#include <sys/time.h>
-#include <sys/uio.h>
-#include <unistd.h>
-
-#include "mincrypt/sha256.h"
-#include "fuse_sideload.h"
-
-#define PACKAGE_FILE_ID   (FUSE_ROOT_ID+1)
-#define EXIT_FLAG_ID      (FUSE_ROOT_ID+2)
-
-#define NO_STATUS         1
-#define NO_STATUS_EXIT    2
-
-struct fuse_data {
-    int ffd;   // file descriptor for the fuse socket
-
-    struct provider_vtab* vtab;
-    void* cookie;
-
-    uint64_t file_size;     // bytes
-
-    uint32_t block_size;    // block size that the adb host is using to send the file to us
-    uint32_t file_blocks;   // file size in block_size blocks
-
-    uid_t uid;
-    gid_t gid;
-
-    uint32_t curr_block;    // cache the block most recently read from the host
-    uint8_t* block_data;
-
-    uint8_t* extra_block;   // another block of storage for reads that
-                            // span two blocks
-
-    uint8_t* hashes;        // SHA-256 hash of each block (all zeros
-                            // if block hasn't been read yet)
-};
-
-static void fuse_reply(struct fuse_data* fd, __u64 unique, const void *data, size_t len)
-{
-    struct fuse_out_header hdr;
-    struct iovec vec[2];
-    int res;
-
-    hdr.len = len + sizeof(hdr);
-    hdr.error = 0;
-    hdr.unique = unique;
-
-    vec[0].iov_base = &hdr;
-    vec[0].iov_len = sizeof(hdr);
-    vec[1].iov_base = /* const_cast */(void*)(data);
-    vec[1].iov_len = len;
-
-    res = writev(fd->ffd, vec, 2);
-    if (res < 0) {
-        printf("*** REPLY FAILED *** %s\n", strerror(errno));
-    }
-}
-
-static int handle_init(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    const struct fuse_init_in* req = data;
-    struct fuse_init_out out;
-    size_t fuse_struct_size;
-
-
-    /* Kernel 2.6.16 is the first stable kernel with struct fuse_init_out
-     * defined (fuse version 7.6). The structure is the same from 7.6 through
-     * 7.22. Beginning with 7.23, the structure increased in size and added
-     * new parameters.
-     */
-    if (req->major != FUSE_KERNEL_VERSION || req->minor < 6) {
-        printf("Fuse kernel version mismatch: Kernel version %d.%d, Expected at least %d.6",
-               req->major, req->minor, FUSE_KERNEL_VERSION);
-        return -1;
-    }
-
-    out.minor = MIN(req->minor, FUSE_KERNEL_MINOR_VERSION);
-    fuse_struct_size = sizeof(out);
-#if defined(FUSE_COMPAT_22_INIT_OUT_SIZE)
-    /* FUSE_KERNEL_VERSION >= 23. */
-
-    /* If the kernel only works on minor revs older than or equal to 22,
-     * then use the older structure size since this code only uses the 7.22
-     * version of the structure. */
-    if (req->minor <= 22) {
-        fuse_struct_size = FUSE_COMPAT_22_INIT_OUT_SIZE;
-    }
-#endif
-
-    out.major = FUSE_KERNEL_VERSION;
-    out.max_readahead = req->max_readahead;
-    out.flags = 0;
-    out.max_background = 32;
-    out.congestion_threshold = 32;
-    out.max_write = 4096;
-    fuse_reply(fd, hdr->unique, &out, fuse_struct_size);
-
-    return NO_STATUS;
-}
-
-static void fill_attr(struct fuse_attr* attr, struct fuse_data* fd,
-                      uint64_t nodeid, uint64_t size, uint32_t mode) {
-    memset(attr, 0, sizeof(*attr));
-    attr->nlink = 1;
-    attr->uid = fd->uid;
-    attr->gid = fd->gid;
-    attr->blksize = 4096;
-
-    attr->ino = nodeid;
-    attr->size = size;
-    attr->blocks = (size == 0) ? 0 : (((size-1) / attr->blksize) + 1);
-    attr->mode = mode;
-}
-
-static int handle_getattr(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    const struct fuse_getattr_in* req = data;
-    struct fuse_attr_out out;
-    memset(&out, 0, sizeof(out));
-    out.attr_valid = 10;
-
-    if (hdr->nodeid == FUSE_ROOT_ID) {
-        fill_attr(&(out.attr), fd, hdr->nodeid, 4096, S_IFDIR | 0555);
-    } else if (hdr->nodeid == PACKAGE_FILE_ID) {
-        fill_attr(&(out.attr), fd, PACKAGE_FILE_ID, fd->file_size, S_IFREG | 0444);
-    } else if (hdr->nodeid == EXIT_FLAG_ID) {
-        fill_attr(&(out.attr), fd, EXIT_FLAG_ID, 0, S_IFREG | 0);
-    } else {
-        return -ENOENT;
-    }
-
-    fuse_reply(fd, hdr->unique, &out, sizeof(out));
-    return (hdr->nodeid == EXIT_FLAG_ID) ? NO_STATUS_EXIT : NO_STATUS;
-}
-
-static int handle_lookup(void* data, struct fuse_data* fd,
-                         const struct fuse_in_header* hdr) {
-    struct fuse_entry_out out;
-    memset(&out, 0, sizeof(out));
-    out.entry_valid = 10;
-    out.attr_valid = 10;
-
-    if (strncmp(FUSE_SIDELOAD_HOST_FILENAME, data,
-                sizeof(FUSE_SIDELOAD_HOST_FILENAME)) == 0) {
-        out.nodeid = PACKAGE_FILE_ID;
-        out.generation = PACKAGE_FILE_ID;
-        fill_attr(&(out.attr), fd, PACKAGE_FILE_ID, fd->file_size, S_IFREG | 0444);
-    } else if (strncmp(FUSE_SIDELOAD_HOST_EXIT_FLAG, data,
-                       sizeof(FUSE_SIDELOAD_HOST_EXIT_FLAG)) == 0) {
-        out.nodeid = EXIT_FLAG_ID;
-        out.generation = EXIT_FLAG_ID;
-        fill_attr(&(out.attr), fd, EXIT_FLAG_ID, 0, S_IFREG | 0);
-    } else {
-        return -ENOENT;
-    }
-
-    fuse_reply(fd, hdr->unique, &out, sizeof(out));
-    return (out.nodeid == EXIT_FLAG_ID) ? NO_STATUS_EXIT : NO_STATUS;
-}
-
-static int handle_open(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    const struct fuse_open_in* req = data;
-
-    if (hdr->nodeid == EXIT_FLAG_ID) return -EPERM;
-    if (hdr->nodeid != PACKAGE_FILE_ID) return -ENOENT;
-
-    struct fuse_open_out out;
-    memset(&out, 0, sizeof(out));
-    out.fh = 10;  // an arbitrary number; we always use the same handle
-    fuse_reply(fd, hdr->unique, &out, sizeof(out));
-    return NO_STATUS;
-}
-
-static int handle_flush(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    return 0;
-}
-
-static int handle_release(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    return 0;
-}
-
-// Fetch a block from the host into fd->curr_block and fd->block_data.
-// Returns 0 on successful fetch, negative otherwise.
-static int fetch_block(struct fuse_data* fd, uint32_t block) {
-    if (block == fd->curr_block) {
-        return 0;
-    }
-
-    if (block >= fd->file_blocks) {
-        memset(fd->block_data, 0, fd->block_size);
-        fd->curr_block = block;
-        return 0;
-    }
-
-    size_t fetch_size = fd->block_size;
-    if (block * fd->block_size + fetch_size > fd->file_size) {
-        // If we're reading the last (partial) block of the file,
-        // expect a shorter response from the host, and pad the rest
-        // of the block with zeroes.
-        fetch_size = fd->file_size - (block * fd->block_size);
-        memset(fd->block_data + fetch_size, 0, fd->block_size - fetch_size);
-    }
-
-    int result = fd->vtab->read_block(fd->cookie, block, fd->block_data, fetch_size);
-    if (result < 0) return result;
-
-    fd->curr_block = block;
-
-    // Verify the hash of the block we just got from the host.
-    //
-    // - If the hash of the just-received data matches the stored hash
-    //   for the block, accept it.
-    // - If the stored hash is all zeroes, store the new hash and
-    //   accept the block (this is the first time we've read this
-    //   block).
-    // - Otherwise, return -EINVAL for the read.
-
-    uint8_t hash[SHA256_DIGEST_SIZE];
-    SHA256_hash(fd->block_data, fd->block_size, hash);
-    uint8_t* blockhash = fd->hashes + block * SHA256_DIGEST_SIZE;
-    if (memcmp(hash, blockhash, SHA256_DIGEST_SIZE) == 0) {
-        return 0;
-    }
-
-    int i;
-    for (i = 0; i < SHA256_DIGEST_SIZE; ++i) {
-        if (blockhash[i] != 0) {
-            fd->curr_block = -1;
-            return -EIO;
-        }
-    }
-
-    memcpy(blockhash, hash, SHA256_DIGEST_SIZE);
-    return 0;
-}
-
-static int handle_read(void* data, struct fuse_data* fd, const struct fuse_in_header* hdr) {
-    const struct fuse_read_in* req = data;
-    struct fuse_out_header outhdr;
-    struct iovec vec[3];
-    int vec_used;
-    int result;
-
-    if (hdr->nodeid != PACKAGE_FILE_ID) return -ENOENT;
-
-    uint64_t offset = req->offset;
-    uint32_t size = req->size;
-
-    // The docs on the fuse kernel interface are vague about what to
-    // do when a read request extends past the end of the file.  We
-    // can return a short read -- the return structure does include a
-    // length field -- but in testing that caused the program using
-    // the file to segfault.  (I speculate that this is due to the
-    // reading program accessing it via mmap; maybe mmap dislikes when
-    // you return something short of a whole page?)  To fix this we
-    // zero-pad reads that extend past the end of the file so we're
-    // always returning exactly as many bytes as were requested.
-    // (Users of the mapped file have to know its real length anyway.)
-
-    outhdr.len = sizeof(outhdr) + size;
-    outhdr.error = 0;
-    outhdr.unique = hdr->unique;
-    vec[0].iov_base = &outhdr;
-    vec[0].iov_len = sizeof(outhdr);
-
-    uint32_t block = offset / fd->block_size;
-    result = fetch_block(fd, block);
-    if (result != 0) return result;
-
-    // Two cases:
-    //
-    //   - the read request is entirely within this block.  In this
-    //     case we can reply immediately.
-    //
-    //   - the read request goes over into the next block.  Note that
-    //     since we mount the filesystem with max_read=block_size, a
-    //     read can never span more than two blocks.  In this case we
-    //     copy the block to extra_block and issue a fetch for the
-    //     following block.
-
-    uint32_t block_offset = offset - (block * fd->block_size);
-
-    if (size + block_offset <= fd->block_size) {
-        // First case: the read fits entirely in the first block.
-
-        vec[1].iov_base = fd->block_data + block_offset;
-        vec[1].iov_len = size;
-        vec_used = 2;
-    } else {
-        // Second case: the read spills over into the next block.
-
-        memcpy(fd->extra_block, fd->block_data + block_offset,
-               fd->block_size - block_offset);
-        vec[1].iov_base = fd->extra_block;
-        vec[1].iov_len = fd->block_size - block_offset;
-
-        result = fetch_block(fd, block+1);
-        if (result != 0) return result;
-        vec[2].iov_base = fd->block_data;
-        vec[2].iov_len = size - vec[1].iov_len;
-        vec_used = 3;
-    }
-
-    if (writev(fd->ffd, vec, vec_used) < 0) {
-        printf("*** READ REPLY FAILED: %s ***\n", strerror(errno));
-    }
-    return NO_STATUS;
-}
-
-int run_fuse_sideload(struct provider_vtab* vtab, void* cookie,
-                      uint64_t file_size, uint32_t block_size)
-{
-    int result;
-
-    // If something's already mounted on our mountpoint, try to remove
-    // it.  (Mostly in case of a previous abnormal exit.)
-    umount2(FUSE_SIDELOAD_HOST_MOUNTPOINT, MNT_FORCE);
-
-    if (block_size < 1024) {
-        fprintf(stderr, "block size (%u) is too small\n", block_size);
-        return -1;
-    }
-    if (block_size > (1<<22)) {   // 4 MiB
-        fprintf(stderr, "block size (%u) is too large\n", block_size);
-        return -1;
-    }
-
-    struct fuse_data fd;
-    memset(&fd, 0, sizeof(fd));
-    fd.vtab = vtab;
-    fd.cookie = cookie;
-    fd.file_size = file_size;
-    fd.block_size = block_size;
-    fd.file_blocks = (file_size == 0) ? 0 : (((file_size-1) / block_size) + 1);
-
-    if (fd.file_blocks > (1<<18)) {
-        fprintf(stderr, "file has too many blocks (%u)\n", fd.file_blocks);
-        result = -1;
-        goto done;
-    }
-
-    fd.hashes = (uint8_t*)calloc(fd.file_blocks, SHA256_DIGEST_SIZE);
-    if (fd.hashes == NULL) {
-        fprintf(stderr, "failed to allocate %d bites for hashes\n",
-                fd.file_blocks * SHA256_DIGEST_SIZE);
-        result = -1;
-        goto done;
-    }
-
-    fd.uid = getuid();
-    fd.gid = getgid();
-
-    fd.curr_block = -1;
-    fd.block_data = (uint8_t*)malloc(block_size);
-    if (fd.block_data == NULL) {
-        fprintf(stderr, "failed to allocate %d bites for block_data\n", block_size);
-        result = -1;
-        goto done;
-    }
-    fd.extra_block = (uint8_t*)malloc(block_size);
-    if (fd.extra_block == NULL) {
-        fprintf(stderr, "failed to allocate %d bites for extra_block\n", block_size);
-        result = -1;
-        goto done;
-    }
-
-    fd.ffd = open("/dev/fuse", O_RDWR);
-    if (fd.ffd < 0) {
-        perror("open /dev/fuse");
-        result = -1;
-        goto done;
-    }
-
-    char opts[256];
-    snprintf(opts, sizeof(opts),
-             ("fd=%d,user_id=%d,group_id=%d,max_read=%u,"
-              "allow_other,rootmode=040000"),
-             fd.ffd, fd.uid, fd.gid, block_size);
-
-    result = mount("/dev/fuse", FUSE_SIDELOAD_HOST_MOUNTPOINT,
-                   "fuse", MS_NOSUID | MS_NODEV | MS_RDONLY | MS_NOEXEC, opts);
-    if (result < 0) {
-        perror("mount");
-        goto done;
-    }
-    uint8_t request_buffer[sizeof(struct fuse_in_header) + PATH_MAX*8];
-    for (;;) {
-        ssize_t len = TEMP_FAILURE_RETRY(read(fd.ffd, request_buffer, sizeof(request_buffer)));
-        if (len == -1) {
-            perror("read request");
-            if (errno == ENODEV) {
-                result = -1;
-                break;
-            }
-            continue;
-        }
-
-        if ((size_t)len < sizeof(struct fuse_in_header)) {
-            fprintf(stderr, "request too short: len=%zu\n", (size_t)len);
-            continue;
-        }
-
-        struct fuse_in_header* hdr = (struct fuse_in_header*) request_buffer;
-        void* data = request_buffer + sizeof(struct fuse_in_header);
-
-        result = -ENOSYS;
-
-        switch (hdr->opcode) {
-             case FUSE_INIT:
-                result = handle_init(data, &fd, hdr);
-                break;
-
-             case FUSE_LOOKUP:
-                result = handle_lookup(data, &fd, hdr);
-                break;
-
-            case FUSE_GETATTR:
-                result = handle_getattr(data, &fd, hdr);
-                break;
-
-            case FUSE_OPEN:
-                result = handle_open(data, &fd, hdr);
-                break;
-
-            case FUSE_READ:
-                result = handle_read(data, &fd, hdr);
-                break;
-
-            case FUSE_FLUSH:
-                result = handle_flush(data, &fd, hdr);
-                break;
-
-            case FUSE_RELEASE:
-                result = handle_release(data, &fd, hdr);
-                break;
-
-            default:
-                fprintf(stderr, "unknown fuse request opcode %d\n", hdr->opcode);
-                break;
-        }
-
-        if (result == NO_STATUS_EXIT) {
-            result = 0;
-            break;
-        }
-
-        if (result != NO_STATUS) {
-            struct fuse_out_header outhdr;
-            outhdr.len = sizeof(outhdr);
-            outhdr.error = result;
-            outhdr.unique = hdr->unique;
-            TEMP_FAILURE_RETRY(write(fd.ffd, &outhdr, sizeof(outhdr)));
-        }
-    }
-
-  done:
-    fd.vtab->close(fd.cookie);
-
-    result = umount2(FUSE_SIDELOAD_HOST_MOUNTPOINT, MNT_DETACH);
-    if (result < 0) {
-        printf("fuse_sideload umount failed: %s\n", strerror(errno));
-    }
-
-    if (fd.ffd) close(fd.ffd);
-    free(fd.hashes);
-    free(fd.block_data);
-    free(fd.extra_block);
-
-    return result;
-}