X-Git-Url: http://git.bytex64.net/?a=blobdiff_plain;f=common%2Fauth.c;h=e2f7407d9cbf8ce69c7b5a6908ceeb424e9d0d5f;hb=d67dd1bf5a247e20141b9907f5a452da73624235;hp=cdfbf85f396fed3cbb2d640db412baa8c5815b73;hpb=96ec261b36bdbb701e05f5ee1aab70dec44085f9;p=blerg.git

diff --git a/common/auth.c b/common/auth.c
index cdfbf85..e2f7407 100644
--- a/common/auth.c
+++ b/common/auth.c
@@ -1,62 +1,294 @@
+/* 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/file.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <crypto_scrypt.h>
 #include "config.h"
+#include "configuration.h"
+#include "database.h"
 #include "auth.h"
 #include "util.h"
-
-#define TOKEN_SIZE 16
+#include "stringring.h"
+#include "md5.h"
 
 int auth_set_password(const char *username, const char *password) {
-	char filename[512];
-	int fd;
+	char filename[FILENAME_MAX];
+	struct auth_v2 auth;
+	int fd, n, r;
 
 	if (!valid_name(username) || !blerg_exists(username))
 		return 0;
 
-	snprintf(filename, 512, "%s/%s/password", DATA_PATH, username);
+	n = strlen(password);
+	if (n > MAX_PASSWORD_LENGTH)
+		return 0;
+
+	/* Clear the auth structure */
+	memset(&auth, 0, sizeof(struct auth_v2));
+
+	/* Set the auth version */
+	auth.header.version = 2;
+
+	/* Gather some salt */
+	fd = open("/dev/urandom", O_RDONLY);
+	if (fd == -1) {
+		perror("Could not open /dev/urandom");
+		return 0;
+	}
+	read(fd, auth.salt, SCRYPT_SALT_SIZE);
+	close(fd);
+
+	r = crypto_scrypt((const uint8_t *)password, n, auth.salt, SCRYPT_SALT_SIZE, SCRYPT_N, SCRYPT_r, SCRYPT_p, auth.password, SCRYPT_OUTPUT_SIZE);
+	if (r != 0) {
+		fprintf(stderr, "Failure in scrypt for %s\n", username);
+		return 0;
+	}
+
+	/* Write the data */
+	snprintf(filename, FILENAME_MAX, "%s/%s/auth", blergconf.data_path, username);
 	fd = open(filename, O_WRONLY | O_CREAT, 0600);
-	write(fd, password, strlen(password));
+	flock(fd, LOCK_EX);
+	write(fd, &auth, sizeof(struct auth_v2));
+	flock(fd, LOCK_UN);
 	close(fd);
-	
+
 	return 1;
 }
 
+int auth_get_password_version(const char *username) {
+	char filename[FILENAME_MAX];
+	int fd;
+	char str[4];
+	struct auth_header ah;
+	int len = 0;
+
+	snprintf(filename, FILENAME_MAX, "%s/%s/auth", blergconf.data_path, username);
+	if (access(filename, F_OK) == 0) {
+		fd = open(filename, O_RDONLY);
+		if (fd == -1)
+			return -1;
+		len = read(fd, &ah, sizeof(struct auth_header));
+		close(fd);
+
+		if (len < 0) {
+			perror("reading auth file");
+			return -1;
+		} else if (len < sizeof(struct auth_header)) {
+			fprintf(stderr, "Short read on while determining auth version for %s", username);
+			return -1;
+		}
+
+		return ah.version;
+	}
+
+	snprintf(filename, FILENAME_MAX, "%s/%s/password_version", blergconf.data_path, username);
+	if (access(filename, F_OK) != 0) {
+		return 0;
+	}
+
+	fd = open(filename, O_RDONLY);
+	if (fd == -1)
+		return -1;
+	len = read(fd, str, 4);
+	close(fd);
+
+	if (len < 0) {
+		perror("auth_get_password_version");
+		return -1;
+	}
+
+	str[len] = 0;
+
+	/* 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];
+	char filename[FILENAME_MAX];
 	int fd;
+	int read_size;
 	int len = 0;
 
 	if (!valid_name(username))
 		return 0;
 
-	sprintf(filename, "%s/%s/password", DATA_PATH, username);
+	switch(auth_get_password_version(username)) {
+	case 0:
+		read_size = MD5_DIGEST_SIZE;
+		break;
+	case 1:
+		read_size = SCRYPT_OUTPUT_SIZE;
+		break;
+	default:
+		return 0;
+	}
+
+	snprintf(filename, FILENAME_MAX, "%s/%s/password", blergconf.data_path, username);
 	fd = open(filename, O_RDONLY);
 	if (fd == -1)
 		return 0;
-	len = read(fd, password, 32);
+	len = read(fd, password, read_size);
 	close(fd);
 
+	if (len < 0) {
+		perror("auth_get_password");
+		return 0;
+	} else if (len < read_size) {
+		fprintf(stderr, "Short read getting password\n");
+		return 0;
+	}
+
 	password[len] = 0;
 
 	return 1;
 }
 
-int auth_check_password(const char *username, const char *password) {
-	char epw[33];
+int auth_get_salt(const char *username, uint8_t *salt) {
+	char filename[FILENAME_MAX];
+	int fd;
+	int len = 0;
+
+	if (!valid_name(username))
+		return 0;
+
+	snprintf(filename, FILENAME_MAX, "%s/%s/password_salt", blergconf.data_path, username);
+	fd = open(filename, O_RDONLY);
+	if (fd == -1)
+		return 0;
+	len = read(fd, salt, SCRYPT_SALT_SIZE);
+	close(fd);
+
+	if (len < 0) {
+		perror("auth_get_salt");
+		return 0;
+	} else if (len < SCRYPT_SALT_SIZE) {
+		fprintf(stderr, "Short read getting salt\n");
+		return 0;
+	}
+
+	return 1;
+}
+
+int auth_check_password_v0(const char *username, const char *password) {
+	char epw[MD5_DIGEST_SIZE + 1];
+	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((unsigned char *)givenpw, &ctx);
+
+	if (strncmp(givenpw, epw, MD5_DIGEST_SIZE) == 0)
+		return 1;
+	else
+		return 0;
+}
+
+int auth_get_data(const char *username, void *data, size_t data_len) {
+	char filename[FILENAME_MAX];
+	int fd;
+	int len = 0;
+
+	if (!valid_name(username))
+		return 0;
+
+	snprintf(filename, FILENAME_MAX, "%s/%s/auth", blergconf.data_path, username);
+	fd = open(filename, O_RDONLY);
+	if (fd == -1)
+		return 0;
+	flock(fd, LOCK_SH);
+	len = read(fd, data, data_len);
+	flock(fd, LOCK_UN);
+	close(fd);
+
+	if (len < 0) {
+		perror("auth_get_data");
+		return 0;
+	} else if (len < data_len) {
+		fprintf(stderr, "Short read getting auth data\n");
+		return 0;
+	}
+
+	return 1;
+}
+
+int auth_check_scrypt(struct auth_v2 *auth, const char *username, const char *password) {
+	unsigned char givenpw[SCRYPT_OUTPUT_SIZE];
+	int r;
+
+	r = crypto_scrypt((const uint8_t *)password, strlen(password), auth->salt, SCRYPT_SALT_SIZE, SCRYPT_N, SCRYPT_r, SCRYPT_p, givenpw, SCRYPT_OUTPUT_SIZE);
+	if (r != 0) {
+		fprintf(stderr, "Failure in scrypt for %s\n", username);
+		return 0;
+	}
+
+	if (memcmp(givenpw, auth->password, SCRYPT_OUTPUT_SIZE) == 0)
 		return 1;
 	else
 		return 0;
 }
 
+int auth_check_password_v1(const char *username, const char *password) {
+	struct auth_v2 auth;
+
+	if (auth_get_password(username, (char *)auth.password) == 0)
+		return 0;
+
+	if (auth_get_salt(username, auth.salt) == 0)
+		return 0;
+
+	return auth_check_scrypt(&auth, username, password);
+}
+
+int auth_check_password_v2(const char *username, const char *password) {
+	struct auth_v2 auth;
+
+	if (auth_get_data(username, (void *) &auth, sizeof(struct auth_v2)) == 0)
+		return 0;
+
+	return auth_check_scrypt(&auth, username, password);
+}
+
+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:
+		if (auth_check_password_v1(username, password)) {
+			/* Refresh to the newest version */
+			auth_set_password(username, password);
+			return 1;
+		} else {
+			return 0;
+		}
+		break;
+	case 2:
+		return auth_check_password_v2(username, password);
+	}
+	fprintf(stderr, "auth_check_password fell through. Bad password version?\n");
+	return 0;
+}
+
 void hexify(char *dst, char *src, int len) {
 	static char hex[] = "0123456789abcdef";
 	int i;
@@ -68,7 +300,7 @@ void hexify(char *dst, char *src, int len) {
 }
 
 char *create_random_token() {
-	unsigned char buf[TOKEN_SIZE];
+	char buf[TOKEN_SIZE];
 	char *token;
 	int rand_fd;
 
@@ -87,70 +319,97 @@ char *create_random_token() {
 	return token;
 }
 
-int auth_login(const char *username, const char *password) {
-	char filename[512];
-	int token_fd;
+char * auth_login(const char *username, const char *password) {
+	char filename[FILENAME_MAX];
+	struct stringring *sr;
+	char *token;
+
 
 	if (!auth_check_password(username, password))
-		return 0;
+		return NULL;
 
-	sprintf(filename, "%s/%s/token", DATA_PATH, username);
-	token_fd = open(filename, O_WRONLY | O_CREAT, 0600);
-	if (token_fd == -1) {
-		perror("Could not open token");
-		return 0;
+	snprintf(filename, FILENAME_MAX, "%s/%s/tokens", blergconf.data_path, username);
+	sr = stringring_open(filename);
+	if (sr == NULL) {
+		return NULL;
 	}
+	token = create_random_token();
+	if (!stringring_add(sr, token)) {
+		free(token);
+		stringring_close(sr);
+		return NULL;
+	}
+	stringring_close(sr);
 
-	char *token = create_random_token();
-	write(token_fd, token, TOKEN_SIZE * 2);
-	close(token_fd);
-	free(token);
-
-	return 1;
+	return token;
 }
 
-int auth_logout(const char *username) {
-	char filename[512];
+int auth_logout(const char *username, const char *token) {
+	char filename[FILENAME_MAX];
+	struct stringring *sr;
+	int ret;
 
 	if (!valid_name(username))
 		return 0;
 
-	sprintf(filename, "%s/%s/token", DATA_PATH, username);
-	if (unlink(filename) == -1)
+	snprintf(filename, FILENAME_MAX, "%s/%s/tokens", blergconf.data_path, username);
+	if (access(filename, F_OK) != 0) {
+		return 0;
+	}
+	sr = stringring_open(filename);
+	if (sr == NULL) {
 		return 0;
+	}
+	ret = stringring_remove(sr, token);
+	stringring_close(sr);
 
-	return 1;
+	return ret;
 }
 
-char *auth_get_token(const char *username) {
-	char filename[512];
-	char *token;
-	int token_fd;
+int auth_check_token(const char *username, const char *given_token) {
+	char filename[FILENAME_MAX];
+	struct stringring *sr;
+	int ret;
 
-	if (!valid_name(username))
+	snprintf(filename, FILENAME_MAX, "%s/%s/tokens", blergconf.data_path, username);
+	if (access(filename, F_OK) != 0) {
 		return 0;
-
-	sprintf(filename, "%s/%s/token", DATA_PATH, username);
-	token_fd = open(filename, O_RDONLY, 0600);
-	if (token_fd == -1) {
-		perror("Could not open token");
-		return NULL;
 	}
+	sr = stringring_open(filename);
+	if (sr == NULL) {
+		return 0;
+	}
+	ret = (stringring_find(sr, given_token, AUTHENTICATION_TIMEOUT) != -1);
+	if (ret == 1) {
+		/* Update token timestamp */
+		stringring_touch(sr, given_token);
+	}
+	stringring_close(sr);
 
-	token = malloc(TOKEN_SIZE * 2 + 1);
-	read(token_fd, token, TOKEN_SIZE * 2);
-	close(token_fd);
-
-	return token;
+	return ret;
 }
 
-int auth_check_token(const char *username, const char *given_token) {
-	char *token = auth_get_token(username);
-	if (token != NULL && given_token != NULL) {
-		int ret = (strncmp(token, given_token, TOKEN_SIZE * 2) == 0);
-		free(token);
-		return ret;
-	} else {
+/* Return a 32-bit integer "counter" that will change when the password is
+ * updated.  Used to invalidate password recovery schemes after the password is
+ * updated.  Returns the counter in the "counter" argument, and returns
+ * true/false on success/failure. */
+int auth_get_counter(const char *username, uint32_t *counter) {
+	struct auth_v2 auth;
+	struct MD5Context ctx;
+	uint8_t md5hash[MD5_DIGEST_SIZE];
+
+	if (auth_get_data(username, (void *) &auth, sizeof(struct auth_v2)) == 0)
 		return 0;
-	}
+
+	/* There's probably going to be some question about using MD5 here.
+	 * All I really need is to quickly and repeatably scramble some bits.
+	 * MD5 can still do that. */
+	MD5Init(&ctx);
+	MD5Update(&ctx, auth.password, SCRYPT_OUTPUT_SIZE);
+	MD5Update(&ctx, auth.salt, SCRYPT_SALT_SIZE);
+	MD5Final((unsigned char *)md5hash, &ctx);
+
+	*counter = ((uint32_t *)md5hash)[0];
+
+	return 1;
 }