1 files changed, 219 insertions, 0 deletions
diff --git a/src/Common/libzip/zip_source_pkware_decode.c b/src/Common/libzip/zip_source_pkware_decode.c
new file mode 100644
index 00000000..b4c482b3
--- /dev/null
+++ b/src/Common/libzip/zip_source_pkware_decode.c
@@ -0,0 +1,219 @@
+/*
+  zip_source_pkware_decode.c -- Traditional PKWARE decryption routines
+  Copyright (C) 2009-2020 Dieter Baron and Thomas Klausner
+
+  This file is part of libzip, a library to manipulate ZIP archives.
+  The authors can be contacted at <info@libzip.org>
+
+  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. The names of the authors may not be used to endorse or promote
+     products derived from this software without specific prior
+     written permission.
+
+  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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 <stdlib.h>
+#include <string.h>
+
+#include "zipint.h"
+
+struct trad_pkware {
+    char *password;
+    zip_pkware_keys_t keys;
+    zip_error_t error;
+};
+
+
+static int decrypt_header(zip_source_t *, struct trad_pkware *);
+static zip_int64_t pkware_decrypt(zip_source_t *, void *, void *, zip_uint64_t, zip_source_cmd_t);
+static struct trad_pkware *trad_pkware_new(const char *password, zip_error_t *error);
+static void trad_pkware_free(struct trad_pkware *);
+
+
+zip_source_t *
+zip_source_pkware_decode(zip_t *za, zip_source_t *src, zip_uint16_t em, int flags, const char *password) {
+    struct trad_pkware *ctx;
+    zip_source_t *s2;
+
+    if (password == NULL || src == NULL || em != ZIP_EM_TRAD_PKWARE) {
+        zip_error_set(&za->error, ZIP_ER_INVAL, 0);
+        return NULL;
+    }
+    if (flags & ZIP_CODEC_ENCODE) {
+        zip_error_set(&za->error, ZIP_ER_ENCRNOTSUPP, 0);
+        return NULL;
+    }
+
+    if ((ctx = trad_pkware_new(password, &za->error)) == NULL) {
+        return NULL;
+    }
+
+    if ((s2 = zip_source_layered(za, src, pkware_decrypt, ctx)) == NULL) {
+        trad_pkware_free(ctx);
+        return NULL;
+    }
+
+    return s2;
+}
+
+
+static int
+decrypt_header(zip_source_t *src, struct trad_pkware *ctx) {
+    zip_uint8_t header[ZIP_CRYPTO_PKWARE_HEADERLEN];
+    struct zip_stat st;
+    zip_int64_t n;
+    bool ok = false;
+
+    if ((n = zip_source_read(src, header, ZIP_CRYPTO_PKWARE_HEADERLEN)) < 0) {
+        zip_error_set_from_source(&ctx->error, src);
+        return -1;
+    }
+
+    if (n != ZIP_CRYPTO_PKWARE_HEADERLEN) {
+        zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
+        return -1;
+    }
+
+    _zip_pkware_decrypt(&ctx->keys, header, header, ZIP_CRYPTO_PKWARE_HEADERLEN);
+
+    if (zip_source_stat(src, &st)) {
+        /* stat failed, skip password validation */
+        return 0;
+    }
+
+    /* password verification - two ways:
+     *  mtime - InfoZIP way, to avoid computing complete CRC before encrypting data
+     *  CRC - old PKWare way
+     */
+
+    if (st.valid & ZIP_STAT_MTIME) {
+        unsigned short dostime, dosdate;
+        _zip_u2d_time(st.mtime, &dostime, &dosdate);
+        if (header[ZIP_CRYPTO_PKWARE_HEADERLEN - 1] == dostime >> 8) {
+            ok = true;
+        }
+    }
+
+    if (st.valid & ZIP_STAT_CRC) {
+        if (header[ZIP_CRYPTO_PKWARE_HEADERLEN - 1] == st.crc >> 24) {
+            ok = true;
+        }
+    }
+
+    if (!ok && ((st.valid & (ZIP_STAT_MTIME | ZIP_STAT_CRC)) != 0)) {
+        zip_error_set(&ctx->error, ZIP_ER_WRONGPASSWD, 0);
+        return -1;
+    }
+
+    return 0;
+}
+
+
+static zip_int64_t
+pkware_decrypt(zip_source_t *src, void *ud, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
+    struct trad_pkware *ctx;
+    zip_int64_t n;
+
+    ctx = (struct trad_pkware *)ud;
+
+    switch (cmd) {
+    case ZIP_SOURCE_OPEN:
+        _zip_pkware_keys_reset(&ctx->keys);
+        _zip_pkware_decrypt(&ctx->keys, NULL, (const zip_uint8_t *)ctx->password, strlen(ctx->password));
+        if (decrypt_header(src, ctx) < 0) {
+            return -1;
+        }
+        return 0;
+
+    case ZIP_SOURCE_READ:
+        if ((n = zip_source_read(src, data, len)) < 0) {
+            zip_error_set_from_source(&ctx->error, src);
+            return -1;
+        }
+
+        _zip_pkware_decrypt(&ctx->keys, (zip_uint8_t *)data, (zip_uint8_t *)data, (zip_uint64_t)n);
+        return n;
+
+    case ZIP_SOURCE_CLOSE:
+        return 0;
+
+    case ZIP_SOURCE_STAT: {
+        zip_stat_t *st;
+
+        st = (zip_stat_t *)data;
+
+        st->encryption_method = ZIP_EM_NONE;
+        st->valid |= ZIP_STAT_ENCRYPTION_METHOD;
+        if (st->valid & ZIP_STAT_COMP_SIZE) {
+            st->comp_size -= ZIP_CRYPTO_PKWARE_HEADERLEN;
+        }
+
+        return 0;
+    }
+
+    case ZIP_SOURCE_SUPPORTS:
+        return zip_source_make_command_bitmap(ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_CLOSE, ZIP_SOURCE_STAT, ZIP_SOURCE_ERROR, ZIP_SOURCE_FREE, ZIP_SOURCE_SUPPORTS_REOPEN, -1);
+
+    case ZIP_SOURCE_ERROR:
+        return zip_error_to_data(&ctx->error, data, len);
+
+    case ZIP_SOURCE_FREE:
+        trad_pkware_free(ctx);
+        return 0;
+
+    default:
+        return zip_source_pass_to_lower_layer(src, data, len, cmd);
+    }
+}
+
+
+static struct trad_pkware *
+trad_pkware_new(const char *password, zip_error_t *error) {
+    struct trad_pkware *ctx;
+
+    if ((ctx = (struct trad_pkware *)malloc(sizeof(*ctx))) == NULL) {
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        return NULL;
+    }
+
+    if ((ctx->password = strdup(password)) == NULL) {
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        free(ctx);
+        return NULL;
+    }
+
+    zip_error_init(&ctx->error);
+
+    return ctx;
+}
+
+
+static void
+trad_pkware_free(struct trad_pkware *ctx) {
+    if (ctx == NULL) {
+        return;
+    }
+
+    free(ctx->password);
+    free(ctx);
+}