Add scrypt library and scrypt support to auth

[blerg.git] / common / auth.c

diff --git a/common/auth.c b/common/auth.c
index 0d40455..6e5f346 100644 (file)
--- a/common/auth.c
+++ b/common/auth.c
@@ -7,19 +7,17 @@
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <crypto_scrypt.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];
-       unsigned char md5pass[MD5_DIGEST_SIZE];
-       struct MD5Context ctx;
-       int fd, n;
+       unsigned char pwhash[SCRYPT_OUTPUT_SIZE];
+       unsigned char salt[SCRYPT_SALT_SIZE];
+       int fd, n, r;
 
        if (!valid_name(username) || !blerg_exists(username))
                return 0;
@@ -28,19 +26,60 @@ int auth_set_password(const char *username, const char *password) {
        if (n > MAX_PASSWORD_LENGTH)
                return 0;
 
-       MD5Init(&ctx);
-       MD5Update(&ctx, username, strlen(username));
-       MD5Update(&ctx, password, n);
-       MD5Final(md5pass, &ctx);
+       /* Gather some salt */
+       fd = open("/dev/urandom", O_RDONLY);
+       if (fd == -1) {
+               perror("Could not open /dev/urandom\n");
+               return 0;
+       }
+       read(fd, salt, SCRYPT_SALT_SIZE);
+       close(fd);
 
+       r = crypto_scrypt(password, n, salt, SCRYPT_SALT_SIZE, SCRYPT_N, SCRYPT_r, SCRYPT_p, pwhash, SCRYPT_OUTPUT_SIZE);
+       if (r != 0) {
+               printf("Failure in scrypt for %s\n", username);
+               return 0;
+       }
+
+       /* Write the password */
        snprintf(filename, 512, "%s/%s/password", DATA_PATH, username);
        fd = open(filename, O_WRONLY | O_CREAT, 0600);
-       write(fd, md5pass, MD5_DIGEST_SIZE);
+       write(fd, pwhash, SCRYPT_OUTPUT_SIZE);
+       close(fd);
+
+       /* Write the salt */
+       snprintf(filename, 512, "%s/%s/password_salt", DATA_PATH, username);
+       fd = open(filename, O_WRONLY | O_CREAT, 0600);
+       write(fd, salt, SCRYPT_SALT_SIZE);
+       close(fd);
+
+       /* Mark this as a version 1 password */
+       snprintf(filename, 512, "%s/%s/password_version", DATA_PATH, username);
+       fd = open(filename, O_WRONLY | O_CREAT, 0600);
+       write(fd, "1\n", 2);
        close(fd);
        
        return 1;
 }
 
+int auth_get_password_version(const char *username) {
+       char filename[512];
+       int fd;
+       char str[4];
+       int version;
+
+       sprintf(filename, "%s/%s/password_version", DATA_PATH, username);
+       if (access(filename, F_OK) != 0) {
+               return 0;
+       }
+
+       fd = open(filename, O_RDONLY);
+       read(fd, str, 4);
+       close(fd);
+       /* strtol returns zero if there isn't a number */
+       return strtol(str, NULL, 10);
+}
+
 int auth_get_password(const char *username, char *password) {
        char filename[512];
        int fd;
@@ -53,7 +92,14 @@ int auth_get_password(const char *username, char *password) {
        fd = open(filename, O_RDONLY);
        if (fd == -1)
                return 0;
-       len = read(fd, password, MD5_DIGEST_SIZE);
+       switch(auth_get_password_version(username)) {
+       case 0:
+               len = read(fd, password, MD5_DIGEST_SIZE);
+               break;
+       case 1:
+               len = read(fd, password, SCRYPT_OUTPUT_SIZE);
+               break;
+       }
        close(fd);
 
        password[len] = 0;
@@ -61,7 +107,24 @@ int auth_get_password(const char *username, char *password) {
        return 1;
 }
 
-int auth_check_password(const char *username, const char *password) {
+int auth_get_salt(const char *username, char *salt) {
+       char filename[512];
+       int fd, len;
+
+       if (!valid_name(username))
+               return 0;
+
+       sprintf(filename, "%s/%s/password_salt", DATA_PATH, username);
+       fd = open(filename, O_RDONLY);
+       if (fd == -1)
+               return 0;
+       len = read(fd, salt, SCRYPT_SALT_SIZE);
+       close(fd);
+
+       return 1;
+}
+
+int auth_check_password_v0(const char *username, const char *password) {
        char epw[MD5_DIGEST_SIZE + 1];
        unsigned char givenpw[MD5_DIGEST_SIZE];
        struct MD5Context ctx;
@@ -80,6 +143,48 @@ int auth_check_password(const char *username, const char *password) {
                return 0;
 }
 
+int auth_check_password_v1(const char *username, const char *password) {
+       unsigned char epw[SCRYPT_OUTPUT_SIZE];
+       unsigned char esalt[SCRYPT_SALT_SIZE];
+       unsigned char givenpw[SCRYPT_OUTPUT_SIZE];
+       int r;
+
+       if (auth_get_password(username, epw) == 0)
+               return 0;
+
+       if (auth_get_salt(username, esalt) == 0)
+               return 0;
+
+       r = crypto_scrypt(password, strlen(password), esalt, SCRYPT_SALT_SIZE, SCRYPT_N, SCRYPT_r, SCRYPT_p, givenpw, SCRYPT_OUTPUT_SIZE);
+       if (r != 0) {
+               printf("Failure in scrypt for %s\n", username);
+               return 0;
+       }
+
+       if (memcmp(givenpw, epw, SCRYPT_OUTPUT_SIZE) == 0)
+               return 1;
+       else
+               return 0;
+}
+
+int auth_check_password(const char *username, const char *password) {
+       int version = auth_get_password_version(username);
+
+       switch(version) {
+       case 0:
+               if (auth_check_password_v0(username, password)) {
+                       /* Refresh to the newest version */
+                       auth_set_password(username, password);
+                       return 1;
+               } else {
+                       return 0;
+               }
+               break;
+       case 1:
+               return auth_check_password_v1(username, password);
+       }
+}
+
 void hexify(char *dst, char *src, int len) {
        static char hex[] = "0123456789abcdef";
        int i;