shachain: allow overriding of number of bits, add cmdline tool.

[ccan] / ccan / crypto / shachain / tools / shachain48.c

diff --git a/ccan/crypto/shachain/tools/shachain48.c b/ccan/crypto/shachain/tools/shachain48.c
new file mode 100644 (file)
index 0000000..5cc9109
--- /dev/null
+++ b/ccan/crypto/shachain/tools/shachain48.c
@@ -0,0 +1,58 @@
+#include <ccan/crypto/shachain/shachain.h>
+#include <ccan/str/hex/hex.h>
+#include <ccan/str/str.h>
+#include <ccan/err/err.h>
+#include <ccan/rbuf/rbuf.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+       if (argc == 2 && streq(argv[1], "--store")) {
+               struct shachain s;
+               struct rbuf rbuf;
+               size_t size = rbuf_good_size(STDIN_FILENO);
+               char *p;
+
+               shachain_init(&s);
+               rbuf_init(&rbuf, STDIN_FILENO, malloc(size), size);
+
+               while ((p = rbuf_read_str(&rbuf, '\n', realloc)) != NULL) {
+                       struct sha256 hash;
+                       unsigned long long idx;
+
+                       if (strstarts(p, "0x"))
+                               p += 2;
+                       if (!hex_decode(p, 64, &hash, sizeof(hash)))
+                               errx(2, "%.*s is not 64 chars of hex", 64, p);
+                       p += 64;
+                       p += strspn(p, " \t");
+                       idx = strtoull(p, NULL, 0);
+                       if (shachain_add_hash(&s, idx, &hash))
+                               printf("OK\n");
+                       else
+                               printf("ERROR\n");
+               }
+       } else if (argc == 3) {
+               struct sha256 seed, hash;
+               const char *p;
+               unsigned long long idx;
+               char hex[65];
+
+               if (strstarts(argv[1], "0x"))
+                       p = argv[1] + 2;
+               else
+                       p = argv[1];
+               idx = strtoull(argv[2], NULL, 0);
+
+               if (!hex_decode(p, 64, &seed, sizeof(seed)))
+                       errx(2, "%s is not 64 chars of hex", p);
+
+               shachain_from_seed(&seed, idx, &hash);
+               hex_encode(&hash, sizeof(hash), hex, sizeof(hex));
+               printf("0x%s\n", hex);
+       } else
+               errx(1, "Usage: shachain --store OR shachain <seed> <index>");
+       return 0;
+}