s3 swat: Add support for anti-XSRF token

2 files changed, 59 insertions, 0 deletions

diff --git a/source3/web/swat.c b/source3/web/swat.c
index 5e66b1c985..353b7faf59 100644
--- a/source3/web/swat.c
+++ b/source3/web/swat.c
@@ -35,6 +35,7 @@
 #include "printing/load.h"
 #include "passdb.h"
 #include "intl/lang_tdb.h"
+#include "../lib/crypto/md5.h"
 #include "lib/param/loadparm.h"
 
 static int demo_mode = False;
@@ -57,6 +58,7 @@ static int iNumNonAutoPrintServices = 0;
 #define DISABLE_USER_FLAG "disable_user_flag"
 #define ENABLE_USER_FLAG "enable_user_flag"
 #define RHOST "remote_host"
+#define XSRF_TOKEN "xsrf"
 
 #define _(x) lang_msg_rotate(talloc_tos(),x)
 
@@ -145,6 +147,58 @@ static char *make_parm_name(const char *label)
 	return parmname;
 }
 
+void get_xsrf_token(const char *username, const char *pass,
+		    const char *formname, char token_str[33])
+{
+	struct MD5Context md5_ctx;
+	uint8_t token[16];
+	int i;
+
+	token_str[0] = '\0';
+	ZERO_STRUCT(md5_ctx);
+	MD5Init(&md5_ctx);
+
+	MD5Update(&md5_ctx, (uint8_t *)formname, strlen(formname));
+	if (username != NULL) {
+		MD5Update(&md5_ctx, (uint8_t *)username, strlen(username));
+	}
+	if (pass != NULL) {
+		MD5Update(&md5_ctx, (uint8_t *)pass, strlen(pass));
+	}
+
+	MD5Final(token, &md5_ctx);
+
+	for(i = 0; i < sizeof(token); i++) {
+		char tmp[3];
+
+		snprintf(tmp, sizeof(tmp), "%02x", token[i]);
+		strncat(token_str, tmp, sizeof(tmp));
+	}
+}
+
+void print_xsrf_token(const char *username, const char *pass,
+		      const char *formname)
+{
+	char token[33];
+
+	get_xsrf_token(username, pass, formname, token);
+	printf("<input type=\"hidden\" name=\"%s\" value=\"%s\">\n",
+	       XSRF_TOKEN, token);
+
+}
+
+bool verify_xsrf_token(const char *formname)
+{
+	char expected[33];
+	const char *username = cgi_user_name();
+	const char *pass = cgi_user_pass();
+	const char *token = cgi_variable_nonull(XSRF_TOKEN);
+
+	get_xsrf_token(username, pass, formname, expected);
+	return (strncmp(expected, token, sizeof(expected)) == 0);
+}
+
+
 /****************************************************************************
   include a lump of html in a page 
 ****************************************************************************/
diff --git a/source3/web/swat_proto.h b/source3/web/swat_proto.h
index 76f9c3c68f..e66c9420db 100644
--- a/source3/web/swat_proto.h
+++ b/source3/web/swat_proto.h
@@ -67,5 +67,10 @@ void status_page(void);
 /* The following definitions come from web/swat.c  */
 
 const char *lang_msg_rotate(TALLOC_CTX *ctx, const char *msgid);
+void get_xsrf_token(const char *username, const char *pass,
+		    const char *formname, char token_str[33]);
+void print_xsrf_token(const char *username, const char *pass,
+		      const char *formname);
+bool verify_xsrf_token(const char *formname);
 
 #endif /*  _SWAT_PROTO_H_  */