Reload user when posting

[blerg.git] / common / auth.c

diff --git a/common/auth.c b/common/auth.c
index 0a3a8f5..0d40455 100644 (file)
--- a/common/auth.c
+++ b/common/auth.c
@@ -1,21 +1,41 @@
+/* Blerg is (C) 2011 The Dominion of Awesome, and is distributed under a
+ * BSD-style license.  Please see the COPYING file for details.
+ */
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include "config.h"
 #include "auth.h"
+#include "util.h"
+#include "md5.h"
+
+#define TOKEN_SIZE 16
+#define MAX_PASSWORD_LENGTH 64
 
 int auth_set_password(const char *username, const char *password) {
        char filename[512];
-       int fd;
+       unsigned char md5pass[MD5_DIGEST_SIZE];
+       struct MD5Context ctx;
+       int fd, n;
+
+       if (!valid_name(username) || !blerg_exists(username))
+               return 0;
 
-       if (!blerg_exists(username))
+       n = strlen(password);
+       if (n > MAX_PASSWORD_LENGTH)
                return 0;
 
+       MD5Init(&ctx);
+       MD5Update(&ctx, username, strlen(username));
+       MD5Update(&ctx, password, n);
+       MD5Final(md5pass, &ctx);
+
        snprintf(filename, 512, "%s/%s/password", DATA_PATH, username);
        fd = open(filename, O_WRONLY | O_CREAT, 0600);
-       write(fd, password, strlen(password));
+       write(fd, md5pass, MD5_DIGEST_SIZE);
        close(fd);
        
        return 1;
@@ -26,11 +46,14 @@ int auth_get_password(const char *username, char *password) {
        int fd;
        int len = 0;
 
+       if (!valid_name(username))
+               return 0;
+
        sprintf(filename, "%s/%s/password", DATA_PATH, username);
        fd = open(filename, O_RDONLY);
        if (fd == -1)
                return 0;
-       len = read(fd, password, 32);
+       len = read(fd, password, MD5_DIGEST_SIZE);
        close(fd);
 
        password[len] = 0;
@@ -39,13 +62,104 @@ int auth_get_password(const char *username, char *password) {
 }
 
 int auth_check_password(const char *username, const char *password) {
-       char epw[33];
+       char epw[MD5_DIGEST_SIZE + 1];
+       unsigned char givenpw[MD5_DIGEST_SIZE];
+       struct MD5Context ctx;
 
        if (auth_get_password(username, epw) == 0)
                return 0;
 
-       if (strncmp(password, epw, 32) == 0)
+       MD5Init(&ctx);
+       MD5Update(&ctx, username, strlen(username));
+       MD5Update(&ctx, password, strlen(password));
+       MD5Final(givenpw, &ctx);
+
+       if (strncmp(givenpw, epw, MD5_DIGEST_SIZE) == 0)
                return 1;
        else
                return 0;
 }
+
+void hexify(char *dst, char *src, int len) {
+       static char hex[] = "0123456789abcdef";
+       int i;
+
+       for (i = 0; i < len; i++) {
+               dst[i * 2]     = hex[(src[i] & 0xF0) >> 4];
+               dst[i * 2 + 1] = hex[src[i] & 0xF];
+       }
+}
+
+char *create_random_token() {
+       unsigned char buf[TOKEN_SIZE];
+       char *token;
+       int rand_fd;
+
+       rand_fd = open("/dev/urandom", O_RDONLY);
+       if (rand_fd == -1) {
+               perror("Could not open /dev/urandom\n");
+               return 0;
+       }
+       read(rand_fd, buf, TOKEN_SIZE);
+       close(rand_fd);
+
+       token = malloc(TOKEN_SIZE * 2 + 1);
+       hexify(token, buf, TOKEN_SIZE);
+       token[TOKEN_SIZE * 2] = 0;
+
+       return token;
+}
+
+char * auth_login(const char *username, const char *password) {
+       char filename[512];
+       int token_fd;
+
+       if (!auth_check_password(username, password))
+               return NULL;
+
+       char *token = create_random_token();
+
+       sprintf(filename, "%s/%s/tokens", DATA_PATH, username);
+       if (access(filename, F_OK) != 0) {
+               if (mkdir(filename, 0700) == -1) {
+                       perror("Could not create auth token dir");
+                       return NULL;
+               }
+       }
+
+       sprintf(filename, "%s/%s/tokens/%s", DATA_PATH, username, token);
+       token_fd = open(filename, O_WRONLY | O_CREAT, 0600);
+       if (token_fd == -1) {
+               perror("Could not open token");
+               return NULL;
+       }
+       close(token_fd);
+
+       return token;
+}
+
+int auth_logout(const char *username, const char *token) {
+       char filename[512];
+
+       if (!valid_name(username))
+               return 0;
+
+       sprintf(filename, "%s/%s/tokens", DATA_PATH, username);
+       if (access(filename, F_OK) != 0) {
+               return 0;
+       }
+
+       sprintf(filename, "%s/%s/tokens/%s", DATA_PATH, username, token);
+       if (unlink(filename) == -1)
+               return 0;
+
+       return 1;
+}
+
+int auth_check_token(const char *username, const char *given_token) {
+       char filename[512];
+
+       sprintf(filename, "%s/%s/tokens/%s", DATA_PATH, username, given_token);
+
+       return (access(filename, F_OK) == 0);
+}