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-rw-r--r--toys/sha1sum.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/toys/sha1sum.c b/toys/sha1sum.c
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+++ b/toys/sha1sum.c
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+/*
+ * Copyright 2007 Rob Landley <rob@landley.net>
+ *
+ * Based on the public domain SHA-1 in C by Steve Reid <steve@edmweb.com>
+ * from http://www.mirrors.wiretapped.net/security/cryptography/hashes/sha1/
+ */
+
+#include <toys.h>
+
+struct sha1 {
+ uint32_t state[5];
+ uint32_t oldstate[5];
+ uint64_t count;
+ union {
+ unsigned char c[64];
+ uint32_t i[16];
+ } buffer;
+};
+
+void sha1_init(struct sha1 *this);
+void sha1_transform(struct sha1 *this);
+void sha1_update(struct sha1 *this, char *data, unsigned int len);
+void sha1_final(struct sha1 *this, char digest[20]);
+
+#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
+
+/* blk0() and blk() perform the initial expand. */
+/* The idea of expanding during the round function comes from SSLeay */
+#if 1
+#define blk0(i) (block[i] = (rol(block[i],24)&0xFF00FF00) \
+ |(rol(block[i],8)&0x00FF00FF))
+#else // big endian?
+#define blk0(i) block[i]
+#endif
+#define blk(i) (block[i&15] = rol(block[(i+13)&15]^block[(i+8)&15] \
+ ^block[(i+2)&15]^block[i&15],1))
+
+static const uint32_t rconsts[]={0x5A827999,0x6ED9EBA1,0x8F1BBCDC,0xCA62C1D6};
+
+/* Hash a single 512-bit block. This is the core of the algorithm. */
+
+void sha1_transform(struct sha1 *this)
+{
+ int i, j, k, count;
+ uint32_t *block = this->buffer.i;
+ uint32_t *rot[5], *temp;
+
+ /* Copy context->state[] to working vars */
+ for (i=0; i<5; i++) {
+ this->oldstate[i] = this->state[i];
+ rot[i] = this->state + i;
+ }
+ /* 4 rounds of 20 operations each. */
+ for (i=count=0; i<4; i++) {
+ for (j=0; j<20; j++) {
+ uint32_t work;
+
+ work = *rot[2] ^ *rot[3];
+ if (!i) work = (work & *rot[1]) ^ *rot[3];
+ else {
+ if (i==2)
+ work = ((*rot[1]|*rot[2])&*rot[3])|(*rot[1]&*rot[2]);
+ else work ^= *rot[1];
+ }
+ if (!i && j<16) work += blk0(count);
+ else work += blk(count);
+ *rot[4] += work + rol(*rot[0],5) + rconsts[i];
+ *rot[1] = rol(*rot[1],30);
+
+ // Rotate by one for next time.
+ temp = rot[4];
+ for (k=4; k; k--) rot[k] = rot[k-1];
+ *rot = temp;
+ count++;
+ }
+ }
+ /* Add the previous values of state[] */
+ for (i=0; i<5; i++) this->state[i] += this->oldstate[i];
+}
+
+
+/* SHA1Init - Initialize new context */
+
+void sha1_init(struct sha1 *this)
+{
+ /* SHA1 initialization constants */
+ this->state[0] = 0x67452301;
+ this->state[1] = 0xEFCDAB89;
+ this->state[2] = 0x98BADCFE;
+ this->state[3] = 0x10325476;
+ this->state[4] = 0xC3D2E1F0;
+ this->count = 0;
+}
+
+/* Run your data through this function. */
+
+void sha1_update(struct sha1 *this, char *data, unsigned int len)
+{
+ unsigned int i, j;
+
+ j = this->count & 63;
+ this->count += len;
+
+ // Enough data to process a frame?
+ if ((j + len) > 63) {
+ i = 64-j;
+ memcpy(this->buffer.c + j, data, i);
+ sha1_transform(this);
+ for ( ; i + 63 < len; i += 64) {
+ memcpy(this->buffer.c, data + i, 64);
+ sha1_transform(this);
+ }
+ j = 0;
+ } else i = 0;
+ // Grab remaining chunk
+ memcpy(this->buffer.c + j, data + i, len - i);
+}
+
+/* Add padding and return the message digest. */
+
+void sha1_final(struct sha1 *this, char digest[20])
+{
+ uint64_t count = this->count << 3;
+ unsigned int i;
+ char buf;
+
+ // End the message by appending a "1" bit to the data, ending with the
+ // message size (in bits, big endian), and adding enough zero bits in
+ // between to pad to the end of the next 64-byte frame. Since our input
+ // up to now has been in whole bytes, we can deal with bytes here too.
+
+ buf = 0x80;
+ do {
+ sha1_update(this, &buf, 1);
+ buf = 0;
+ } while ((this->count & 63) != 56);
+ for (i = 0; i < 8; i++)
+ this->buffer.c[56+i] = count >> (8*(7-i));
+ sha1_transform(this);
+
+ for (i = 0; i < 20; i++)
+ digest[i] = this->state[i>>2] >> ((3-(i & 3)) * 8);
+ /* Wipe variables */
+ memset(this, 0, sizeof(struct sha1));
+}
+
+// Callback for loopfiles()
+
+static void do_sha1(int fd, char *name)
+{
+ struct sha1 this;
+ int len;
+
+ sha1_init(&this);
+ for (;;) {
+ len = read(fd, toybuf, sizeof(toybuf));
+ if (len<1) break;
+ sha1_update(&this, toybuf, len);
+ }
+ sha1_final(&this, toybuf);
+ for (len = 0; len < 20; len++) printf("%02x", toybuf[len]);
+ printf(" %s\n", name);
+}
+
+void sha1sum_main(void)
+{
+ loopfiles(toys.optargs, do_sha1);
+}