third_party/swtpm/patches/0002-swtpm_localca-replace-gmp-mpz-dependency-with-boring.patch

From 9410d7d0e3093380bb9d5cff3241107ff55435dd Mon Sep 17 00:00:00 2001
From: Serge Bazanski <serge@monogon.tech>
Date: Tue, 4 Jun 2024 12:06:17 +0200
Subject: [PATCH 2/4] swtpm_localca: replace gmp/mpz dependency with boringssl
 bignum

---
 src/swtpm_localca/swtpm_localca.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/swtpm_localca/swtpm_localca.c b/src/swtpm_localca/swtpm_localca.c
index 2842f22..d42d3a2 100644
--- a/src/swtpm_localca/swtpm_localca.c
+++ b/src/swtpm_localca/swtpm_localca.c
@@ -24,7 +24,8 @@
 
 #include "glib/glib.h"
 
-#include <gmp.h>
+#include <openssl/bn.h>
+#include <openssl/crypto.h>
 
 #include "swtpm_conf.h"
 #include "swtpm_utils.h"
@@ -313,7 +314,8 @@ static int get_next_serial(const gchar *certserial, const gchar *lockfile,
     g_autofree gchar *buffer = NULL;
     char serialbuffer[50];
     size_t buffer_len;
-    mpz_t serial;
+    BIGNUM *serial = BN_new();
+    char *serial_dec = NULL;
     int lockfd;
     int ret = 1;
 
@@ -328,22 +330,18 @@ static int get_next_serial(const gchar *certserial, const gchar *lockfile,
     if (read_file(certserial, &buffer, &buffer_len) != 0)
         goto error;
 
-    mpz_init(serial);
-
     if (buffer_len > 0 && buffer_len <= 49) {
         memcpy(serialbuffer, buffer, buffer_len);
         serialbuffer[buffer_len] = 0;
 
-        if (gmp_sscanf(serialbuffer, "%Zu", serial) != 1)
-            goto new_serial;
-        mpz_add_ui(serial, serial, 1);
-
-        if ((mpz_sizeinbase(serial, 2) + 7) / 8 > 20)
+        if (BN_dec2bn(&serial, serialbuffer) == 0)
             goto new_serial;
+        BN_add_word(serial, 1);
 
-        if (gmp_snprintf(serialbuffer,
+        serial_dec = BN_bn2dec(serial);
+        if (snprintf(serialbuffer,
                          sizeof(serialbuffer),
-                         "%Zu", serial) >= (int)sizeof(serialbuffer))
+                         "%s", serial_dec) >= (int)sizeof(serialbuffer))
             goto new_serial;
     } else {
 new_serial:
@@ -356,10 +354,12 @@ new_serial:
     write_file(certserial, (unsigned char *)*serial_str, strlen(*serial_str));
     ret = 0;
 
-    mpz_clear(serial);
-
 error:
     unlock_file(lockfd);
+    if (serial_dec) {
+        OPENSSL_free(serial_dec);
+    }
+    BN_free(serial);
 
     return ret;
 }
-- 
2.42.0