X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Flib%2Fdigest.c;fp=src%2Flib%2Fdigest.c;h=132f27e33b2f7c9aa0db3f7541f893b5d6b921fc;hb=e4169f77f892fefc66a97439d295d3e09ef3e2f0;hp=0000000000000000000000000000000000000000;hpb=4fb2a47294e74ba2fea809ad06d2378982270329;p=deb_shairplay.git

diff --git a/src/lib/digest.c b/src/lib/digest.c
new file mode 100644
index 0000000..132f27e
--- /dev/null
+++ b/src/lib/digest.c
@@ -0,0 +1,153 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "compat.h"
+#include "utils.h"
+#include "crypto/crypto.h"
+
+void
+digest_md5_to_hex(const unsigned char *md5buf, char *md5hex)
+{
+	int i;
+	for (i=0; i<MD5_SIZE*2; i++) {
+		int val = (i%2) ? md5buf[i/2]&0x0f : (md5buf[i/2]&0xf0)>>4;
+		md5hex[i] = (val<10) ? '0'+val : 'a'+(val-10);
+	}
+}
+
+void
+digest_get_response(const char *username, const char *realm,
+                    const char *password, const char *nonce,
+                    const char *method, const char *uri,
+                    char *response)
+{
+	MD5_CTX md5ctx;
+	unsigned char md5buf[MD5_SIZE];
+	char md5hex[MD5_SIZE*2];
+
+	/* Calculate first inner MD5 hash */
+	MD5_Init(&md5ctx);
+	MD5_Update(&md5ctx, (const unsigned char *)username, strlen(username));
+	MD5_Update(&md5ctx, (const unsigned char *)":", 1);
+	MD5_Update(&md5ctx, (const unsigned char *)realm, strlen(realm));
+	MD5_Update(&md5ctx, (const unsigned char *)":", 1);
+	MD5_Update(&md5ctx, (const unsigned char *)password, strlen(password));
+	MD5_Final(md5buf, &md5ctx);
+	digest_md5_to_hex(md5buf, md5hex);
+
+	/* Calculate second inner MD5 hash */
+	MD5_Init(&md5ctx);
+	MD5_Update(&md5ctx, (const unsigned char *)method, strlen(method));
+	MD5_Update(&md5ctx, (const unsigned char *)":", 1);
+	MD5_Update(&md5ctx, (const unsigned char *)uri, strlen(uri));
+	MD5_Final(md5buf, &md5ctx);
+
+	/* Calculate outer MD5 hash */
+	MD5_Init(&md5ctx);
+	MD5_Update(&md5ctx, (const unsigned char *)md5hex, sizeof(md5hex));
+	MD5_Update(&md5ctx, (const unsigned char *)":", 1);
+	MD5_Update(&md5ctx, (const unsigned char *)nonce, strlen(nonce));
+	MD5_Update(&md5ctx, (const unsigned char *)":", 1);
+	digest_md5_to_hex(md5buf, md5hex);
+	MD5_Update(&md5ctx, (const unsigned char *)md5hex, sizeof(md5hex));
+	MD5_Final(md5buf, &md5ctx);
+
+	/* Store the final result to response */
+	digest_md5_to_hex(md5buf, response);
+}
+
+void
+digest_generate_nonce(char *result, int resultlen)
+{
+	MD5_CTX md5ctx;
+	unsigned char md5buf[MD5_SIZE];
+	char md5hex[MD5_SIZE*2];
+	unsigned int time;
+
+	SYSTEM_GET_TIME(time);
+
+	MD5_Init(&md5ctx);
+	MD5_Update(&md5ctx, (unsigned char *)&time, sizeof(time));
+	MD5_Final(md5buf, &md5ctx);
+	digest_md5_to_hex(md5buf, md5hex);
+
+	strncpy(result, md5hex, resultlen-1);
+	result[resultlen-1] = '\0';
+}
+
+int
+digest_is_valid(const char *our_realm, const char *password,
+                const char *our_nonce, const char *method,
+                const char *authorization)
+{
+	char *auth;
+	char *current;
+	char *value;
+	int success;
+
+	/* Get values from authorization */
+	char *username = NULL;
+	char *realm = NULL;
+	char *nonce = NULL;
+	char *uri = NULL;
+	char *response = NULL;
+
+	/* Buffer for our response */
+	char our_response[MD5_SIZE*2+1];
+
+	if (!authorization) {
+		return 0;
+	}
+	current = auth = strdup(authorization);
+	if (!auth) {
+		return 0;
+	}
+
+	/* Check that the type is digest */
+	if (strncmp("Digest", current, 6)) {
+		free(auth);
+		return 0;
+	}
+	current += 6;
+
+	while ((value = utils_strsep(&current, ",")) != NULL) {
+		char *first, *last;
+
+		/* Find first and last characters */
+		first = value;
+		last = value+strlen(value)-1;
+
+		/* Trim spaces from the value */
+		while (*first == ' ' && first < last) first++;
+		while (*last == ' ' && last > first) last--;
+
+		/* Validate the last character */
+		if (*last != '"') continue;
+		else *last = '\0';
+
+		/* Store value if it is relevant */
+		if (!strncmp("username=\"", first, 10))
+			username = first+10;
+		if (!strncmp("realm=\"", first, 7))
+			realm = first+7;
+		if (!strncmp("nonce=\"", first, 7))
+			nonce = first+7;
+		if (!strncmp("uri=\"", first, 5))
+			uri = first+5;
+		if (!strncmp("response=\"", first, 10))
+			response = first+10;
+	}
+
+	/* Calculate our response */
+	memset(our_response, 0, sizeof(our_response));
+	digest_get_response(username, realm, password, nonce,
+	                    method, uri, our_response);
+	success = !strcmp(response, our_response);
+	free(auth);
+
+	return success;
+}
+
+