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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
commitb5896ba9f6047e7031e2bdee0622d543e11a6734 (patch)
treefd7b460593a2fee1be579bec5697e6d887ea3421 /src/util/hex_code.c
parentInitial commit. (diff)
downloadpostfix-upstream.tar.xz
postfix-upstream.zip
Adding upstream version 3.4.23.upstream/3.4.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--src/util/hex_code.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/src/util/hex_code.c b/src/util/hex_code.c
new file mode 100644
index 0000000..9e89035
--- /dev/null
+++ b/src/util/hex_code.c
@@ -0,0 +1,168 @@
+/*++
+/* NAME
+/* hex_code 3
+/* SUMMARY
+/* encode/decode data, hexadecimal style
+/* SYNOPSIS
+/* #include <hex_code.h>
+/*
+/* VSTRING *hex_encode(result, in, len)
+/* VSTRING *result;
+/* const char *in;
+/* ssize_t len;
+/*
+/* VSTRING *hex_decode(result, in, len)
+/* VSTRING *result;
+/* const char *in;
+/* ssize_t len;
+/* DESCRIPTION
+/* hex_encode() takes a block of len bytes and encodes it as one
+/* upper-case null-terminated string. The result value is
+/* the result argument.
+/*
+/* hex_decode() performs the opposite transformation on
+/* lower-case, upper-case or mixed-case input. The result
+/* value is the result argument. The result is null terminated,
+/* whether or not that makes sense.
+/* DIAGNOSTICS
+/* hex_decode() returns a null pointer when the input contains
+/* characters not in the hexadecimal alphabet.
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <ctype.h>
+#include <string.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <mymalloc.h>
+#include <vstring.h>
+#include <hex_code.h>
+
+/* Application-specific. */
+
+static const unsigned char hex_chars[] = "0123456789ABCDEF";
+
+#define UCHAR_PTR(x) ((const unsigned char *)(x))
+
+/* hex_encode - raw data to encoded */
+
+VSTRING *hex_encode(VSTRING *result, const char *in, ssize_t len)
+{
+ const unsigned char *cp;
+ int ch;
+ ssize_t count;
+
+ VSTRING_RESET(result);
+ for (cp = UCHAR_PTR(in), count = len; count > 0; count--, cp++) {
+ ch = *cp;
+ VSTRING_ADDCH(result, hex_chars[(ch >> 4) & 0xf]);
+ VSTRING_ADDCH(result, hex_chars[ch & 0xf]);
+ }
+ VSTRING_TERMINATE(result);
+ return (result);
+}
+
+/* hex_decode - encoded data to raw */
+
+VSTRING *hex_decode(VSTRING *result, const char *in, ssize_t len)
+{
+ const unsigned char *cp;
+ ssize_t count;
+ unsigned int hex;
+ unsigned int bin;
+
+ VSTRING_RESET(result);
+ for (cp = UCHAR_PTR(in), count = len; count > 0; cp += 2, count -= 2) {
+ if (count < 2)
+ return (0);
+ hex = cp[0];
+ if (hex >= '0' && hex <= '9')
+ bin = (hex - '0') << 4;
+ else if (hex >= 'A' && hex <= 'F')
+ bin = (hex - 'A' + 10) << 4;
+ else if (hex >= 'a' && hex <= 'f')
+ bin = (hex - 'a' + 10) << 4;
+ else
+ return (0);
+ hex = cp[1];
+ if (hex >= '0' && hex <= '9')
+ bin |= (hex - '0');
+ else if (hex >= 'A' && hex <= 'F')
+ bin |= (hex - 'A' + 10);
+ else if (hex >= 'a' && hex <= 'f')
+ bin |= (hex - 'a' + 10);
+ else
+ return (0);
+ VSTRING_ADDCH(result, bin);
+ }
+ VSTRING_TERMINATE(result);
+ return (result);
+}
+
+#ifdef TEST
+
+ /*
+ * Proof-of-concept test program: convert to hexadecimal and back.
+ */
+
+#define STR(x) vstring_str(x)
+#define LEN(x) VSTRING_LEN(x)
+
+int main(int unused_argc, char **unused_argv)
+{
+ VSTRING *b1 = vstring_alloc(1);
+ VSTRING *b2 = vstring_alloc(1);
+ char *test = "this is a test";
+
+#define DECODE(b,x,l) { \
+ if (hex_decode((b),(x),(l)) == 0) \
+ msg_panic("bad hex: %s", (x)); \
+ }
+#define VERIFY(b,t) { \
+ if (strcmp((b), (t)) != 0) \
+ msg_panic("bad test: %s", (b)); \
+ }
+
+ hex_encode(b1, test, strlen(test));
+ DECODE(b2, STR(b1), LEN(b1));
+ VERIFY(STR(b2), test);
+
+ hex_encode(b1, test, strlen(test));
+ hex_encode(b2, STR(b1), LEN(b1));
+ hex_encode(b1, STR(b2), LEN(b2));
+ DECODE(b2, STR(b1), LEN(b1));
+ DECODE(b1, STR(b2), LEN(b2));
+ DECODE(b2, STR(b1), LEN(b1));
+ VERIFY(STR(b2), test);
+
+ hex_encode(b1, test, strlen(test));
+ hex_encode(b2, STR(b1), LEN(b1));
+ hex_encode(b1, STR(b2), LEN(b2));
+ hex_encode(b2, STR(b1), LEN(b1));
+ hex_encode(b1, STR(b2), LEN(b2));
+ DECODE(b2, STR(b1), LEN(b1));
+ DECODE(b1, STR(b2), LEN(b2));
+ DECODE(b2, STR(b1), LEN(b1));
+ DECODE(b1, STR(b2), LEN(b2));
+ DECODE(b2, STR(b1), LEN(b1));
+ VERIFY(STR(b2), test);
+
+ vstring_free(b1);
+ vstring_free(b2);
+ return (0);
+}
+
+#endif