journalctl: output FSS key as QR code on generating

1 files changed, 127 insertions, 0 deletions

diff --git a/src/journal/journal-qrcode.c b/src/journal/journal-qrcode.c
new file mode 100644
index 0000000000..b4dab8e86a
--- /dev/null
+++ b/src/journal/journal-qrcode.c
@@ -0,0 +1,127 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+#include <qrencode.h>
+
+#include "journal-qrcode.h"
+
+#define WHITE_ON_BLACK "\033[40;37;1m"
+#define NORMAL "\033[0m"
+
+static void print_border(FILE *output, unsigned width) {
+        unsigned x, y;
+
+        /* Four rows of border */
+        for (y = 0; y < 4; y += 2) {
+                fputs(WHITE_ON_BLACK, output);
+
+                for (x = 0; x < 4 + width + 4; x++)
+                        fputs("\342\226\210", output);
+
+                fputs(NORMAL "\n", output);
+        }
+}
+
+int print_qr_code(FILE *output, const void *seed, size_t seed_size, uint64_t start, uint64_t interval, const char *hn, sd_id128_t mahcine) {
+        FILE *f;
+        char *url = NULL;
+        size_t url_size = 0, i;
+        QRcode* qr;
+        unsigned x, y;
+
+        assert(seed);
+        assert(seed_size > 0);
+
+        f = open_memstream(&url, &url_size);
+        if (!f)
+                return -ENOMEM;
+
+        fputs("fss://", f);
+
+        for (i = 0; i < seed_size; i++) {
+                if (i > 0 && i % 3 == 0)
+                        fputc('-', f);
+                fprintf(f, "%02x", ((uint8_t*) seed)[i]);
+        }
+
+        fprintf(f, "/%llx-%llx\n", (unsigned long long) start, (unsigned long long) interval);
+
+        if (hn)
+                fprintf(f, "?hostname=%s", hn);
+
+        if (ferror(f)) {
+                fclose(f);
+                free(url);
+                return -ENOMEM;
+        }
+
+        fclose(f);
+
+        qr = QRcode_encodeString(url, 0, QR_ECLEVEL_L, QR_MODE_8, 1);
+        free(url);
+
+        if (!qr)
+                return -ENOMEM;
+
+        print_border(output, qr->width);
+
+        for (y = 0; y < (unsigned) qr->width; y += 2) {
+                const uint8_t *row1, *row2;
+
+                row1 = qr->data + qr->width * y;
+                row2 = row1 + qr->width;
+
+                fputs(WHITE_ON_BLACK, output);
+                for (x = 0; x < 4; x++)
+                        fputs("\342\226\210", output);
+
+                for (x = 0; x < (unsigned) qr->width; x ++) {
+                        bool a, b;
+
+                        a = row1[x] & 1;
+                        b = (y+1) < (unsigned) qr->width ? (row2[x] & 1) : false;
+
+                        if (a && b)
+                                fputc(' ', output);
+                        else if (a)
+                                fputs("\342\226\204", output);
+                        else if (b)
+                                fputs("\342\226\200", output);
+                        else
+                                fputs("\342\226\210", output);
+                }
+
+                for (x = 0; x < 4; x++)
+                        fputs("\342\226\210", output);
+                fputs(NORMAL "\n", output);
+        }
+
+        print_border(output, qr->width);
+
+        QRcode_free(qr);
+        return 0;
+}