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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:49:25 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:49:25 +0000
commit464df1d5e5ab1322e2dd0a7796939fff1aeefa9a (patch)
tree6a403684e0978f0287d7f0ec0e5aab1fd31a59e1 /lib/ext2fs/digest_encode.c
parentInitial commit. (diff)
downloade2fsprogs-464df1d5e5ab1322e2dd0a7796939fff1aeefa9a.tar.xz
e2fsprogs-464df1d5e5ab1322e2dd0a7796939fff1aeefa9a.zip
Adding upstream version 1.47.0.upstream/1.47.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/ext2fs/digest_encode.c')
-rw-r--r--lib/ext2fs/digest_encode.c187
1 files changed, 187 insertions, 0 deletions
diff --git a/lib/ext2fs/digest_encode.c b/lib/ext2fs/digest_encode.c
new file mode 100644
index 0000000..075963f
--- /dev/null
+++ b/lib/ext2fs/digest_encode.c
@@ -0,0 +1,187 @@
+/*
+ * lib/ext2fs/digest_encode.c
+ *
+ * A function to encode a digest using 64 characters that are valid in a
+ * filename per ext2fs rules.
+ *
+ * Written by Uday Savagaonkar, 2014.
+ *
+ * Copyright 2014 Google Inc. All Rights Reserved.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#include "ext2fs.h"
+
+static const char *lookup_table =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,";
+
+/**
+ * ext2fs_digest_encode() -
+ *
+ * Encodes the input digest using characters from the set [a-zA-Z0-9_+].
+ * The encoded string is roughly 4/3 times the size of the input string.
+ */
+int ext2fs_digest_encode(const char *src, int len, char *dst)
+{
+ int i = 0, bits = 0, ac = 0;
+ char *cp = dst;
+
+ while (i < len) {
+ ac += (((unsigned char) src[i]) << bits);
+ bits += 8;
+ do {
+ *cp++ = lookup_table[ac & 0x3f];
+ ac >>= 6;
+ bits -= 6;
+ } while (bits >= 6);
+ i++;
+ }
+ if (bits)
+ *cp++ = lookup_table[ac & 0x3f];
+ return cp - dst;
+}
+
+int ext2fs_digest_decode(const char *src, int len, char *dst)
+{
+ int i = 0, bits = 0, ac = 0;
+ const char *p;
+ char *cp = dst;
+
+ while (i < len) {
+ p = strchr(lookup_table, src[i]);
+ if (p == NULL || src[i] == 0)
+ return -1;
+ ac += (p - lookup_table) << bits;
+ bits += 6;
+ if (bits >= 8) {
+ *cp++ = ac & 0xff;
+ ac >>= 8;
+ bits -= 8;
+ }
+ i++;
+ }
+ if (ac)
+ return -1;
+ return cp - dst;
+}
+
+
+#ifdef UNITTEST
+static const struct {
+ unsigned char d[32];
+ unsigned int len;
+ const char *ed;
+} tests[] = {
+ { { 0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14,
+ 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24,
+ 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c,
+ 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55 }, 32,
+ "jDLxChJ,cQhm7TPyZ+WukcirBROZbOJTkWZmbgnU4WF"
+ },
+ { { 0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea,
+ 0x41, 0x41, 0x40, 0xde, 0x5d, 0xae, 0x22, 0x23,
+ 0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17, 0x7a, 0x9c,
+ 0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad }, 32,
+ "6inF,+YAPreQBBk3d5qIjA7AhNqlXoHn0Cx,hJPAV0K"
+ },
+ { { 0x24, 0x8d, 0x6a, 0x61, 0xd2, 0x06, 0x38, 0xb8,
+ 0xe5, 0xc0, 0x26, 0x93, 0x0c, 0x3e, 0x60, 0x39,
+ 0xa3, 0x3c, 0xe4, 0x59, 0x64, 0xff, 0x21, 0x67,
+ 0xf6, 0xec, 0xed, 0xd4, 0x19, 0xdb, 0x06, 0xc1 }, 32,
+ "k0oahJtB4gb5AbykM4DY5MKPknFZ,HyZ2ze7Unx2GEM"
+ },
+ { { 0x00, }, 1,
+ "AA"
+ },
+ { { 0x01, }, 1,
+ "BA"
+ },
+ { { 0x01, 0x02 }, 2,
+ "BIA"
+ },
+ { { 0x01, 0x02, 0x03 }, 3,
+ "BIwA"
+ },
+ { { 0x01, 0x02, 0x03, 0x04 }, 4,
+ "BIwAEA"
+ },
+ { { 0x01, 0x02, 0x03, 0x04, 0xff }, 5,
+ "BIwAE8P"
+ },
+ { { 0x01, 0x02, 0x03, 0x04, 0xff, 0xfe }, 6,
+ "BIwAE8v,"
+ },
+ { { 0x01, 0x02, 0x03, 0x04, 0xff, 0xfe, 0xfd }, 7,
+ "BIwAE8v,9D"
+ },
+};
+
+int main(int argc, char **argv)
+{
+ int i, ret, len;
+ int errors = 0;
+ char tmp[1024], tmp2[1024];
+
+ if (argc == 3 && !strcmp(argv[1], "encode")) {
+ memset(tmp, 0, sizeof(tmp));
+ ext2fs_digest_encode(argv[2], strlen(argv[2]), tmp);
+ puts(tmp);
+ exit(0);
+ }
+ if (argc == 3 && !strcmp(argv[1], "decode")) {
+ memset(tmp, 0, sizeof(tmp));
+ ret = ext2fs_digest_decode(argv[2], strlen(argv[2]), tmp);
+ puts(tmp);
+ fprintf(stderr, "returned %d\n", ret);
+ exit(0);
+ }
+ for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {
+ memset(tmp, 0, sizeof(tmp));
+ ret = ext2fs_digest_encode((const char *) tests[i].d,
+ tests[i].len, tmp);
+ len = strlen(tmp);
+ printf("Test Digest %d (returned %d): ", i, ret);
+ if (ret != len) {
+ printf("FAILED returned %d, string length was %d\n",
+ ret, len);
+ errors++;
+ continue;
+ } else if (strcmp(tmp, tests[i].ed) != 0) {
+ printf("FAILED: got %s, expected %s\n", tmp,
+ tests[i].ed);
+ errors++;
+ continue;
+ }
+ ret = ext2fs_digest_decode(tmp, len, tmp2);
+ if (ret != tests[i].len) {
+ printf("FAILED decode returned %d, expected %d\n",
+ ret, tests[i].len);
+ errors++;
+ continue;
+ }
+ if (memcmp(tmp2, tests[i].d, ret) != 0) {
+ puts("FAILED: decode mismatched");
+ errors++;
+ continue;
+ }
+ printf("OK\n");
+ }
+ for (i = 1; i < argc; i++) {
+ memset(tmp, 0, sizeof(tmp));
+ ret = ext2fs_digest_encode(argv[i], strlen(argv[i]), tmp);
+ len = strlen(tmp);
+ printf("Digest of '%s' is '%s' (returned %d, length %d)\n",
+ argv[i], tmp, ret, len);
+ }
+ return errors;
+}
+
+#endif /* UNITTEST */