From: Stephan Bosch <stephan.bosch@open-xchange.com>
Date: Mon, 26 Sep 2022 20:21:39 +0000 (+0200)
Subject: auth: auth-scram - Rename Hi() to auth_scram_hi() and make it public.
X-Git-Tag: 2.4.0~3149
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=669de97f49d84926e2941dc3096171105cd75cb3;p=thirdparty%2Fdovecot%2Fcore.git

auth: auth-scram - Rename Hi() to auth_scram_hi() and make it public.
---

diff --git a/src/auth/Makefile.am b/src/auth/Makefile.am
index 3789546596..3b95dfdeb0 100644
--- a/src/auth/Makefile.am
+++ b/src/auth/Makefile.am
@@ -63,6 +63,7 @@ auth_LDFLAGS = -export-dynamic
 libpassword_la_SOURCES = \
 	crypt-blowfish.c \
 	mycrypt.c \
+	auth-scram.c \
 	password-scheme.c \
 	password-scheme-crypt.c \
 	password-scheme-md5crypt.c \
@@ -181,6 +182,7 @@ headers = \
 	passdb-blocking.h \
 	passdb-cache.h \
 	passdb-template.h \
+	auth-scram.h \
 	password-scheme.h \
 	userdb.h \
 	userdb-blocking.h \
diff --git a/src/auth/auth-scram.c b/src/auth/auth-scram.c
index abdcb3a854..50be682e14 100644
--- a/src/auth/auth-scram.c
+++ b/src/auth/auth-scram.c
@@ -1,12 +1,34 @@
-static void
-Hi(const struct hash_method *hmethod, const unsigned char *str, size_t str_size,
-   const unsigned char *salt, size_t salt_size, unsigned int i,
-   unsigned char *result)
+/* Copyright (c) 2022-2023 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "hmac.h"
+
+#include "auth-scram.h"
+
+void auth_scram_hi(const struct hash_method *hmethod,
+		   const unsigned char *str, size_t str_size,
+		   const unsigned char *salt, size_t salt_size, unsigned int i,
+		   unsigned char *result)
 {
 	struct hmac_context ctx;
 	unsigned char U[hmethod->digest_size];
 	unsigned int j, k;
 
+	/* Hi(str, salt, i):
+
+	   U1   := HMAC(str, salt + INT(1))
+	   U2   := HMAC(str, U1)
+	   ...
+	   Ui-1 := HMAC(str, Ui-2)
+	   Ui   := HMAC(str, Ui-1)
+
+	   Hi := U1 XOR U2 XOR ... XOR Ui
+
+	    where "i" is the iteration count, "+" is the string concatenation
+	    operator, and INT(g) is a 4-octet encoding of the integer g, most
+	    significant octet first.
+	*/
+
 	/* Calculate U1 */
 	hmac_init(&ctx, str, str_size, hmethod);
 	hmac_update(&ctx, salt, salt_size);
diff --git a/src/auth/auth-scram.h b/src/auth/auth-scram.h
new file mode 100644
index 0000000000..d8ef1029f5
--- /dev/null
+++ b/src/auth/auth-scram.h
@@ -0,0 +1,9 @@
+#ifndef AUTH_SCRAM_H
+#define AUTH_SCRAM_H
+
+void auth_scram_hi(const struct hash_method *hmethod,
+		   const unsigned char *str, size_t str_size,
+		   const unsigned char *salt, size_t salt_size, unsigned int i,
+		   unsigned char *result);
+
+#endif
diff --git a/src/auth/password-scheme-scram.c b/src/auth/password-scheme-scram.c
index bb58456386..e6cdc62e87 100644
--- a/src/auth/password-scheme-scram.c
+++ b/src/auth/password-scheme-scram.c
@@ -17,6 +17,7 @@
 #include "sha1.h"
 #include "sha2.h"
 #include "str.h"
+#include "auth-scram.h"
 #include "password-scheme.h"
 
 /* SCRAM allowed iteration count range. RFC says it SHOULD be at least 4096 */
@@ -25,8 +26,6 @@
 
 #define SCRAM_DEFAULT_ITERATE_COUNT 4096
 
-#include "auth-scram.c"
-
 int scram_scheme_parse(const struct hash_method *hmethod, const char *name,
 		       const unsigned char *credentials, size_t size,
 		       unsigned int *iter_count_r, const char **salt_r,
@@ -97,8 +96,9 @@ int scram_verify(const struct hash_method *hmethod, const char *scheme_name,
 	salt = buffer_get_data(t_base64_decode_str(salt_base64), &salt_len);
 
 	/* FIXME: credentials should be SASLprepped UTF8 data here */
-	Hi(hmethod, (const unsigned char *)plaintext, strlen(plaintext),
-	   salt, salt_len, iter_count, salted_password);
+	auth_scram_hi(hmethod,
+		      (const unsigned char *)plaintext, strlen(plaintext),
+		      salt, salt_len, iter_count, salted_password);
 
 	/* Calculate ClientKey */
 	hmac_init(&ctx, salted_password, sizeof(salted_password), hmethod);
@@ -143,8 +143,9 @@ void scram_generate(const struct hash_method *hmethod, const char *plaintext,
 	base64_encode(salt, sizeof(salt), str);
 
 	/* FIXME: credentials should be SASLprepped UTF8 data here */
-	Hi(hmethod, (const unsigned char *)plaintext, strlen(plaintext), salt,
-	   sizeof(salt), rounds, salted_password);
+	auth_scram_hi(hmethod,
+		      (const unsigned char *)plaintext, strlen(plaintext),
+		      salt, sizeof(salt), rounds, salted_password);
 
 	/* Calculate ClientKey */
 	hmac_init(&ctx, salted_password, sizeof(salted_password), hmethod);