add utilities for calculating http digest hashes

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/uclient-utils.c b/uclient-utils.c
index 0d09974..66a4f15 100644
--- a/uclient-utils.c
+++ b/uclient-utils.c
@@ -1,7 +1,11 @@
 #include <stdint.h>
 #include <stdlib.h>
+#include <string.h>
 #include <ctype.h>
 
+#include <libubox/md5.h>
+#include <libubox/utils.h>
+
 #include "uclient-utils.h"
 
 static const char *b64 =
@@ -75,3 +79,67 @@ int uclient_urldecode(const char *in, char *out, bool decode_plus)
 	*out = 0;
 	return ret;
 }
+
+static char hex_digit(char val)
+{
+	val += val > 9 ? 'a' - 10 : '0';
+	return val;
+}
+
+void bin_to_hex(char *dest, const void *buf, int len)
+{
+	const uint8_t *data = buf;
+	int i;
+
+	for (i = 0; i < len; i++) {
+		*(dest++) = hex_digit(data[i] >> 4);
+		*(dest++) = hex_digit(data[i] & 0xf);
+	}
+	*dest = 0;
+}
+
+static void http_create_hash(char *dest, const char * const * str, int n_str)
+{
+	uint32_t hash[4];
+	md5_ctx_t md5;
+	int i;
+
+	md5_begin(&md5);
+	for (i = 0; i < n_str; i++) {
+		if (i)
+			md5_hash(":", 1, &md5);
+		md5_hash(str[i], strlen(str[i]), &md5);
+	}
+	md5_end(hash, &md5);
+	bin_to_hex(dest, &hash, sizeof(hash));
+}
+
+void http_digest_calculate_auth_hash(char *dest, const char *user, const char *realm, const char *password)
+{
+	const char *hash_str[] = {
+		user,
+		realm,
+		password
+	};
+
+	http_create_hash(dest, hash_str, ARRAY_SIZE(hash_str));
+}
+
+void http_digest_calculate_response(char *dest, const struct http_digest_data *data)
+{
+	const char *h_a2_strings[] = {
+		data->method,
+		data->uri,
+	};
+	const char *resp_strings[] = {
+		data->auth_hash,
+		data->nonce,
+		data->nc,
+		data->cnonce,
+		data->qop,
+		dest, /* initialized to H(A2) first */
+	};
+
+	http_create_hash(dest, h_a2_strings, ARRAY_SIZE(h_a2_strings));
+	http_create_hash(dest, resp_strings, ARRAY_SIZE(resp_strings));
+}