rename test.py to importpkg.py

1 files changed, 319 insertions, 0 deletions

diff --git a/importpkg.py b/importpkg.py
new file mode 100755
index 0000000..a45720a
--- /dev/null
+++ b/importpkg.py
@@ -0,0 +1,319 @@
+#!/usr/bin/python
+"""
+CREATE TABLE package (package TEXT PRIMARY KEY, version TEXT, architecture TEXT);
+CREATE TABLE content (package TEXT, filename TEXT, size INTEGER, function TEXT, hash TEXT, FOREIGN KEY (package) REFERENCES package(package));
+CREATE TABLE dependency (package TEXT, required TEXT, FOREIGN KEY (package) REFERENCES package(package), FOREIGN KEY (required) REFERENCES package(package));
+CREATE INDEX content_package_index ON content (package);
+CREATE INDEX content_hash_index ON content (hash);
+"""
+
+import hashlib
+import sqlite3
+import struct
+import sys
+import tarfile
+import zlib
+
+from debian.debian_support import version_compare
+from debian import deb822
+import lzma
+
+class ArReader(object):
+    global_magic = b"!<arch>\n"
+    file_magic = b"`\n"
+
+    def __init__(self, fileobj):
+        self.fileobj = fileobj
+        self.remaining = None
+        self.padding = 0
+
+    def skip(self, length):
+        while length:
+            data = self.fileobj.read(min(4096, length))
+            if not data:
+                raise ValueError("archive truncated")
+            length -= len(data)
+
+    def read_magic(self):
+        data = self.fileobj.read(len(self.global_magic))
+        if data != self.global_magic:
+            raise ValueError("ar global header not found")
+        self.remaining = 0
+
+    def read_entry(self):
+        self.skip_current_entry()
+        if self.padding:
+            if self.fileobj.read(1) != '\n':
+                raise ValueError("missing ar padding")
+            self.padding = 0
+        file_header = self.fileobj.read(60)
+        if not file_header:
+            raise EOFError("end of archive found")
+        parts = struct.unpack("16s 12s 6s 6s 8s 10s 2s", file_header)
+        parts = [p.rstrip(" ") for p in parts]
+        if parts.pop() != self.file_magic:
+            raise ValueError("ar file header not found")
+        self.remaining = int(parts[5])
+        self.padding = self.remaining % 2
+        return parts[0] # name
+
+    def skip_current_entry(self):
+        self.skip(self.remaining)
+        self.remaining = 0
+
+    def read(self, length=None):
+        if length is None:
+            length = self.remaining
+        else:
+            length = min(self.remaining, length)
+        data = self.fileobj.read(length)
+        self.remaining -= len(data)
+        return data
+
+class XzStream(object):
+    blocksize = 65536
+
+    def __init__(self, fileobj):
+        self.fileobj = fileobj
+        self.decomp = lzma.LZMADecompressor()
+        self.buff = b""
+
+    def read(self, length):
+        data = True
+        while True:
+            if len(self.buff) >= length:
+                ret = self.buff[:length]
+                self.buff = self.buff[length:]
+                return ret
+            elif not data: # read EOF in last iteration
+                ret = self.buff
+                self.buff = b""
+                return ret
+            data = self.fileobj.read(self.blocksize)
+            if data:
+                self.buff += self.decomp.decompress(data)
+            else:
+                self.buff += self.decomp.flush()
+
+class MultiHash(object):
+    def __init__(self, *hashes):
+        self.hashes = hashes
+
+    def update(self, data):
+        for hasher in self.hashes:
+            hasher.update(data)
+
+class HashBlacklist(object):
+    def __init__(self, hasher, blacklist=set()):
+        self.hasher = hasher
+        self.blacklist = blacklist
+        self.update = self.hasher.update
+        self.name = hasher.name
+
+    def hexdigest(self):
+        digest = self.hasher.hexdigest()
+        if digest in self.blacklist:
+            return None
+        return digest
+
+class GzipDecompressor(object):
+    def __init__(self):
+        self.inbuffer = b""
+        self.decompressor = None # zlib.decompressobj(-zlib.MAX_WBITS)
+
+    def decompress(self, data):
+        if self.decompressor:
+            data = self.decompressor.decompress(data)
+            if not self.decompressor.unused_data:
+                return data
+            unused_data = self.decompressor.unused_data
+            self.decompressor = None
+            return data + self.decompress(unused_data)
+        self.inbuffer += data
+        skip = 10
+        if len(self.inbuffer) < skip:
+            return b""
+        if not self.inbuffer.startswith(b"\037\213\010"):
+            raise ValueError("gzip magic not found")
+        flag = ord(self.inbuffer[3])
+        if flag & 4:
+            if len(self.inbuffer) < skip + 2:
+                return b""
+            length, = struct.unpack("<H", self.inbuffer[skip:skip+2])
+            skip += 2 + length
+        for field in (8, 16):
+            if flag & field:
+                length = self.inbuffer.find("\0", skip)
+                if length < 0:
+                    return b""
+                skip = length + 1
+        if flag & 2:
+            skip += 2
+        if len(self.inbuffer) < skip:
+            return b""
+        data = self.inbuffer[skip:]
+        self.inbuffer = b""
+        self.decompressor = zlib.decompressobj(-zlib.MAX_WBITS)
+        return self.decompress(data)
+
+    @property
+    def unused_data(self):
+        if self.decompressor:
+            return self.decompressor.unused_data
+        else:
+            return self.inbuffer
+
+    def flush(self):
+        if not self.decompressor:
+            return b""
+        return self.decompressor.flush()
+
+    def copy(self):
+        new = GzipDecompressor()
+        new.inbuffer = self.inbuffer
+        if self.decompressor:
+            new.decompressor = self.decompressor.copy()
+        return new
+
+class DecompressedHash(object):
+    def __init__(self, decompressor, hashobj):
+        self.decompressor = decompressor
+        self.hashobj = hashobj
+
+    def update(self, data):
+        self.hashobj.update(self.decompressor.decompress(data))
+
+    def hexdigest(self):
+        if not hasattr(self.decompressor, "flush"):
+            return self.hashobj.hexdigest()
+        tmpdecomp = self.decompressor.copy()
+        data = tmpdecomp.flush()
+        tmphash = self.hashobj.copy()
+        tmphash.update(data)
+        return tmphash.hexdigest()
+
+class SuppressingHash(object):
+    def __init__(self, hashobj, exceptions=()):
+        self.hashobj = hashobj
+        self.exceptions = exceptions
+
+    def update(self, data):
+        if self.hashobj:
+            try:
+                self.hashobj.update(data)
+            except self.exceptions:
+                self.hashobj = None
+
+    def hexdigest(self):
+        if self.hashobj:
+            try:
+                return self.hashobj.hexdigest()
+            except self.exceptions:
+                self.hashobj = None
+        return None
+
+def hash_file(hashobj, filelike, blocksize=65536):
+    data = filelike.read(blocksize)
+    while data:
+        hashobj.update(data)
+        data = filelike.read(blocksize)
+    return hashobj
+
+boring_sha512_hashes = set((
+    # ""
+    "cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e",
+    # "\n"
+    "be688838ca8686e5c90689bf2ab585cef1137c999b48c70b92f67a5c34dc15697b5d11c982ed6d71be1e1e7f7b4e0733884aa97c3f7a339a8ed03577cf74be09"))
+
+def sha512_nontrivial():
+    return HashBlacklist(hashlib.sha512(), boring_sha512_hashes)
+
+def gziphash():
+    hashobj = DecompressedHash(GzipDecompressor(), hashlib.sha512())
+    hashobj = SuppressingHash(hashobj, (ValueError, zlib.error))
+    hashobj.name = "gzip_sha512"
+    return HashBlacklist(hashobj, boring_sha512_hashes)
+
+def get_hashes(tar):
+    for elem in tar:
+        if not elem.isreg(): # excludes hard links as well
+            continue
+        hasher = MultiHash(sha512_nontrivial(), gziphash())
+        hasher = hash_file(hasher, tar.extractfile(elem))
+        for hashobj in hasher.hashes:
+            hashvalue = hashobj.hexdigest()
+            if hashvalue:
+                yield (elem.name, elem.size, hashobj.name, hashvalue)
+
+def process_package(db, filelike):
+    cur = db.cursor()
+    af = ArReader(filelike)
+    af.read_magic()
+    state = "start"
+    while True:
+        try:
+            name = af.read_entry()
+        except EOFError:
+            break
+        if name == "control.tar.gz":
+            if state != "start":
+                raise ValueError("unexpected control.tar.gz")
+            state = "control"
+            tf = tarfile.open(fileobj=af, mode="r|gz")
+            for elem in tf:
+                if elem.name != "./control":
+                    continue
+                if state != "control":
+                    raise ValueError("duplicate control file")
+                state = "control_file"
+                control = tf.extractfile(elem).read()
+                control = deb822.Packages(control)
+                package = control["package"].encode("ascii")
+                version = control["version"].encode("ascii")
+                architecture = control["architecture"].encode("ascii")
+
+                cur.execute("SELECT version FROM package WHERE package = ?;",
+                            (package,))
+                row = cur.fetchone()
+                if row and version_compare(row[0], version) > 0:
+                    return # already seen a newer package
+
+                cur.execute("DELETE FROM package WHERE package = ?;",
+                            (package,))
+                cur.execute("DELETE FROM content WHERE package = ?;",
+                            (package,))
+                cur.execute("INSERT INTO package (package, version, architecture) VALUES (?, ?, ?);",
+                            (package, version, architecture))
+                depends = control.relations.get("depends", [])
+                depends = set(dep[0]["name"].encode("ascii")
+                              for dep in depends if len(dep) == 1)
+                cur.execute("DELETE FROM dependency WHERE package = ?;",
+                            (package,))
+                cur.executemany("INSERT INTO dependency (package, required) VALUES (?, ?);",
+                                ((package, dep) for dep in depends))
+                break
+            continue
+        elif name == "data.tar.gz":
+            tf = tarfile.open(fileobj=af, mode="r|gz")
+        elif name == "data.tar.bz2":
+            tf = tarfile.open(fileobj=af, mode="r|bz2")
+        elif name == "data.tar.xz":
+            zf = XzStream(af)
+            tf = tarfile.open(fileobj=zf, mode="r|")
+        else:
+            continue
+        if state != "control_file":
+            raise ValueError("missing control file")
+        for name, size, function, hexhash in get_hashes(tf):
+            cur.execute("INSERT INTO content (package, filename, size, function, hash) VALUES (?, ?, ?, ?, ?);",
+                        (package, name.decode("utf8"), size, function, hexhash))
+        db.commit()
+        return
+    raise ValueError("data.tar not found")
+
+def main():
+    db = sqlite3.connect("test.sqlite3")
+    process_package(db, sys.stdin)
+
+if __name__ == "__main__":
+    main()