From: Tollef Fog Heen <tfheen@err.no>
Date: Mon, 12 Oct 2009 08:25:38 +0000 (+0200)
Subject: Add utility functions
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b3b7ad20996e659957178725a34e119e6d01ee96;p=yubikey-server-c

Add utility functions
---

diff --git a/src/util.c b/src/util.c
new file mode 100644
index 0000000..94d7793
--- /dev/null
+++ b/src/util.c
@@ -0,0 +1,172 @@
+
+#include <malloc.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+#include <assert.h>
+#include "util.h"
+
+void *ysc_memdup(void *p, size_t len)
+{
+	void *r;
+	r = malloc(len);
+	assert(r != NULL);
+	memcpy(r, p, len);
+	return r;
+}
+
+size_t ysc_nstrstr(const char *haystack, const char *needle)
+{
+	size_t n = 0;
+	while ((haystack = strstr(haystack, needle)) != NULL) {
+		n++;
+		haystack += strlen(needle);
+	}
+	return n;
+}
+
+
+/* Like strftime, but better, calls strftime under the hood
+   %N => nanoseconds (not implemented)
+   %v => milliseconds
+
+   if tv is null, call gettimeofday for you
+*/
+
+size_t ysc_strftime(char *s, size_t max, const char *format,
+		    const struct timeval *tv) {
+	struct tm tm;
+	int i, j, flen;
+	struct timeval tvv;
+	/* '%v' is two bytes less than what a %v needs */
+	size_t fdup_len = strlen(format) + ysc_nstrstr(format, "%v") * 2;
+	char *fdup = malloc(fdup_len); /* XXX check failure */
+	size_t r;
+
+	if (tv == NULL)
+	  assert(gettimeofday(&tvv, NULL) == 0);
+	else {
+	  memcpy(&tvv, tv, sizeof(struct timeval));
+	}
+	gmtime_r(&tvv.tv_sec, &tm);
+	/* Do %N and %v first, then hand off to strftime */
+	flen = strlen(format);
+	for (i = 0, j = 0; i < flen; i++, j++) {
+		if (format[i] == '%') {
+			switch (format[i+1]) {
+/*			case 'N':
+				break;
+*/
+			case 'v':
+				j += snprintf(fdup+j, 4, "%.3zd",
+					      tvv.tv_usec / 1000);
+				i++;
+				continue;
+				break;
+			default:
+				fdup[j] = format[i];
+				continue;
+			}
+		} else {
+			fdup[j] = format[i];
+		}
+	}
+	r = strftime(s, max, fdup, &tm);
+	free(fdup);
+	return r;
+}
+
+/* Base 64 functions */
+
+/*
+ * AUTHOR:         Bob Trower 08/04/01
+ *
+ * COPYRIGHT:      Copyright (c) Trantor Standard Systems Inc., 2001
+ *
+ * LICENCE:        Copyright (c) 2001 Bob Trower, Trantor Standard Systems Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+unsigned char cb64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static void ysc_b64_encodeblock(unsigned char in[3], unsigned char out[4], int len)
+{
+	out[0] = cb64[in[0] >> 2];
+	out[1] = cb64[((in[0] & 0x03) << 4) | ((in[1] & 0xf0) >> 4)];
+	out[2] = (unsigned char) (len > 1 ? cb64[((in[1] & 0x0f) << 2) |
+						 ((in[2] & 0xc0) >> 6)] : '=');
+	out[3] = (unsigned char) (len > 2 ? cb64[in[2] & 0x3f] : '=');
+}
+
+char *ysc_b64_encode(char *s, ssize_t len)
+{
+	char *r = malloc((len/3+1)*4+1);
+	char *tmp = r;
+	unsigned char out[4];
+
+	while (len > 0) {
+		ysc_b64_encodeblock((unsigned char*)s, out, len);
+		memcpy(tmp, out, 4);
+		tmp += 4;
+		len -= 3;
+		s += 3;
+	}
+	return r;
+}
+
+static void ysc_b64_decodeblock(unsigned const char in[4], unsigned char out[3])
+{
+	out[0] = (unsigned char) ((in[0] - 'A') << 2 | (in[1] - 'A') >> 4);
+	out[1] = (unsigned char) ((in[1] - 'A') << 4 | (in[2] - 'A') >> 2);
+	out[2] = (unsigned char) ((((in[2] - 'A') << 6) & 0xc0) | (in[3] - 'A'));
+}
+
+ssize_t ysc_b64_decode(char *s, char **decoded)
+{
+	ssize_t len = strlen(s);
+	char *tmp;
+	unsigned char out[3];
+	ssize_t r = 0;
+
+	*decoded = malloc((len/4+1)*3+1);
+	tmp = *decoded;
+	if ((len % 4) != 0) {
+		return 0;
+		/* XXX free memory */
+	}
+
+	while (*s != '\0') {
+		ysc_b64_decodeblock((unsigned char*)s, out);
+		memcpy(tmp, out, 3);
+		tmp += 3;
+		if (s[2] == '=') {
+			r += 1;
+		} else if (s[3] == '=') {
+			r += 2;
+		} else {
+			r += 3;
+		}
+		s += 4;
+	}
+	return r;
+}
diff --git a/src/util.h b/src/util.h
new file mode 100644
index 0000000..5a2e8dc
--- /dev/null
+++ b/src/util.h
@@ -0,0 +1,17 @@
+
+#ifndef ysc_util_h__
+#define ysc_util_h__
+
+#include <sys/types.h>
+
+void *ysc_memdup(void *p, size_t len);
+size_t ysc_nstrstr(const char *haystack, const char *needle);
+
+size_t ysc_strftime(char *s, size_t max, const char *format,
+		    const struct timeval *tv);
+
+char *ysc_b64_encode(char *s, ssize_t len);
+ssize_t ysc_b64_decode(char *s, char **r);
+
+
+#endif /* ysc_util_h */