libutil - sha1 functions.

diff --git a/include/minix/sha1.h b/include/minix/sha1.h
new file mode 100644 (file)
index 0000000..e56234c
--- /dev/null
+++ b/include/minix/sha1.h
@@ -0,0 +1,31 @@
+/*     $NetBSD: sha1.h,v 1.6 2008/10/08 14:28:14 joerg Exp $   */
+
+/*
+ * SHA-1 in C
+ * By Steve Reid <steve@edmweb.com>
+ * 100% Public Domain
+ */
+
+#ifndef _NBCOMPAT_SYS_SHA1_H_
+#define        _NBCOMPAT_SYS_SHA1_H_
+
+#include <stdint.h>
+
+#define SHA1_DIGEST_LENGTH             20
+#define SHA1_DIGEST_STRING_LENGTH      41
+
+typedef struct {
+       uint32_t state[5];
+       uint32_t count[2];  
+       unsigned char buffer[64];
+} SHA1_CTX;
+  
+void   SHA1Transform(uint32_t state[5], const unsigned char buffer[64]);
+void   SHA1Init(SHA1_CTX *context);
+void   SHA1Update(SHA1_CTX *context, const unsigned char *data, unsigned int len);
+void   SHA1Final(unsigned char digest[20], SHA1_CTX *context);
+char   *SHA1End(SHA1_CTX *, char *);
+char   *SHA1File(char *, char *);
+char   *SHA1Data(const unsigned char *, size_t, char *);
+
+#endif /* _NBCOMPAT_SYS_SHA1_H_ */

diff --git a/lib/libutil/sha1.c b/lib/libutil/sha1.c
new file mode 100644 (file)
index 0000000..53269bc
--- /dev/null
+++ b/lib/libutil/sha1.c
@@ -0,0 +1,295 @@
+/*     $NetBSD: sha1.c,v 1.8 2008/10/06 12:36:20 joerg Exp $   */
+/*     $OpenBSD: sha1.c,v 1.9 1997/07/23 21:12:32 kstailey Exp $       */
+
+/*
+ * SHA-1 in C
+ * By Steve Reid <steve@edmweb.com>
+ * 100% Public Domain
+ *
+ * Test Vectors (from FIPS PUB 180-1)
+ * "abc"
+ *   A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
+ * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
+ *   84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
+ * A million repetitions of "a"
+ *   34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
+ */
+
+#define SHA1HANDSOFF           /* Copies data before messing with it. */
+
+#if defined(_KERNEL) || defined(_STANDALONE)
+#include <sys/param.h>
+#include <sys/sha1.h>
+#include <sys/systm.h>
+#define _DIAGASSERT(x) (void)0
+#else
+#if 0
+#include "namespace.h"
+#endif
+#include <sys/types.h>
+#include <assert.h>
+#include <minix/sha1.h>
+#include <string.h>
+#endif
+
+#if HAVE_NBTOOL_CONFIG_H
+#include "nbtool_config.h"
+#endif
+#define _DIAGASSERT assert
+
+/*
+ * XXX Kludge until there is resolution regarding mem*() functions
+ * XXX in the kernel.
+ */
+#if defined(_KERNEL) || defined(_STANDALONE)
+#define        memcpy(s, d, l)         bcopy((d), (s), (l))
+#endif
+
+#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
+
+/*
+ * blk0() and blk() perform the initial expand.
+ * I got the idea of expanding during the round function from SSLeay
+ */
+#if BYTE_ORDER == LITTLE_ENDIAN
+# define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
+    |(rol(block->l[i],8)&0x00FF00FF))
+#else
+# define blk0(i) block->l[i]
+#endif
+#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
+    ^block->l[(i+2)&15]^block->l[i&15],1))
+
+/*
+ * (R0+R1), R2, R3, R4 are the different operations (rounds) used in SHA1
+ */
+#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
+#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
+#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
+#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
+#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
+
+
+#if 0
+#if !defined(_KERNEL) && defined(__weak_alias)
+__weak_alias(SHA1Transform,_SHA1Transform)
+__weak_alias(SHA1Init,_SHA1Init)
+__weak_alias(SHA1Update,_SHA1Update)
+__weak_alias(SHA1Final,_SHA1Final)
+#endif
+#endif
+
+typedef union {
+    unsigned char c[64];
+    unsigned int l[16];
+} CHAR64LONG16;
+
+/* old sparc64 gcc could not compile this */
+#undef SPARC64_GCC_WORKAROUND
+#if defined(__sparc64__) && defined(__GNUC__) && __GNUC__ < 3
+#define SPARC64_GCC_WORKAROUND
+#endif
+
+#ifdef SPARC64_GCC_WORKAROUND
+void do_R01(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *);
+void do_R2(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *);
+void do_R3(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *);
+void do_R4(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *);
+
+#define nR0(v,w,x,y,z,i) R0(*v,*w,*x,*y,*z,i)
+#define nR1(v,w,x,y,z,i) R1(*v,*w,*x,*y,*z,i)
+#define nR2(v,w,x,y,z,i) R2(*v,*w,*x,*y,*z,i)
+#define nR3(v,w,x,y,z,i) R3(*v,*w,*x,*y,*z,i)
+#define nR4(v,w,x,y,z,i) R4(*v,*w,*x,*y,*z,i)
+
+void
+do_R01(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *block)
+{
+    nR0(a,b,c,d,e, 0); nR0(e,a,b,c,d, 1); nR0(d,e,a,b,c, 2); nR0(c,d,e,a,b, 3);
+    nR0(b,c,d,e,a, 4); nR0(a,b,c,d,e, 5); nR0(e,a,b,c,d, 6); nR0(d,e,a,b,c, 7);
+    nR0(c,d,e,a,b, 8); nR0(b,c,d,e,a, 9); nR0(a,b,c,d,e,10); nR0(e,a,b,c,d,11);
+    nR0(d,e,a,b,c,12); nR0(c,d,e,a,b,13); nR0(b,c,d,e,a,14); nR0(a,b,c,d,e,15);
+    nR1(e,a,b,c,d,16); nR1(d,e,a,b,c,17); nR1(c,d,e,a,b,18); nR1(b,c,d,e,a,19);
+}
+
+void
+do_R2(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *block)
+{
+    nR2(a,b,c,d,e,20); nR2(e,a,b,c,d,21); nR2(d,e,a,b,c,22); nR2(c,d,e,a,b,23);
+    nR2(b,c,d,e,a,24); nR2(a,b,c,d,e,25); nR2(e,a,b,c,d,26); nR2(d,e,a,b,c,27);
+    nR2(c,d,e,a,b,28); nR2(b,c,d,e,a,29); nR2(a,b,c,d,e,30); nR2(e,a,b,c,d,31);
+    nR2(d,e,a,b,c,32); nR2(c,d,e,a,b,33); nR2(b,c,d,e,a,34); nR2(a,b,c,d,e,35);
+    nR2(e,a,b,c,d,36); nR2(d,e,a,b,c,37); nR2(c,d,e,a,b,38); nR2(b,c,d,e,a,39);
+}
+
+void
+do_R3(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *block)
+{
+    nR3(a,b,c,d,e,40); nR3(e,a,b,c,d,41); nR3(d,e,a,b,c,42); nR3(c,d,e,a,b,43);
+    nR3(b,c,d,e,a,44); nR3(a,b,c,d,e,45); nR3(e,a,b,c,d,46); nR3(d,e,a,b,c,47);
+    nR3(c,d,e,a,b,48); nR3(b,c,d,e,a,49); nR3(a,b,c,d,e,50); nR3(e,a,b,c,d,51);
+    nR3(d,e,a,b,c,52); nR3(c,d,e,a,b,53); nR3(b,c,d,e,a,54); nR3(a,b,c,d,e,55);
+    nR3(e,a,b,c,d,56); nR3(d,e,a,b,c,57); nR3(c,d,e,a,b,58); nR3(b,c,d,e,a,59);
+}
+
+void
+do_R4(uint32_t *a, uint32_t *b, uint32_t *c, uint32_t *d, uint32_t *e, CHAR64LONG16 *block)
+{
+    nR4(a,b,c,d,e,60); nR4(e,a,b,c,d,61); nR4(d,e,a,b,c,62); nR4(c,d,e,a,b,63);
+    nR4(b,c,d,e,a,64); nR4(a,b,c,d,e,65); nR4(e,a,b,c,d,66); nR4(d,e,a,b,c,67);
+    nR4(c,d,e,a,b,68); nR4(b,c,d,e,a,69); nR4(a,b,c,d,e,70); nR4(e,a,b,c,d,71);
+    nR4(d,e,a,b,c,72); nR4(c,d,e,a,b,73); nR4(b,c,d,e,a,74); nR4(a,b,c,d,e,75);
+    nR4(e,a,b,c,d,76); nR4(d,e,a,b,c,77); nR4(c,d,e,a,b,78); nR4(b,c,d,e,a,79);
+}
+#endif
+
+/*
+ * Hash a single 512-bit block. This is the core of the algorithm.
+ */
+void SHA1Transform(state, buffer)
+    uint32_t state[5];
+    const unsigned char buffer[64];
+{
+    uint32_t a, b, c, d, e;
+    CHAR64LONG16 *block;
+
+#ifdef SHA1HANDSOFF
+    CHAR64LONG16 workspace;
+#endif
+
+    _DIAGASSERT(buffer != 0);
+    _DIAGASSERT(state != 0);
+
+#ifdef SHA1HANDSOFF
+    block = &workspace;
+    (void)memcpy(block, buffer, 64);
+#else
+    block = (CHAR64LONG16 *)(void *)buffer;
+#endif
+
+    /* Copy context->state[] to working vars */
+    a = state[0];
+    b = state[1];
+    c = state[2];
+    d = state[3];
+    e = state[4];
+
+#ifdef SPARC64_GCC_WORKAROUND
+    do_R01(&a, &b, &c, &d, &e, block);
+    do_R2(&a, &b, &c, &d, &e, block);
+    do_R3(&a, &b, &c, &d, &e, block);
+    do_R4(&a, &b, &c, &d, &e, block);
+#else
+    /* 4 rounds of 20 operations each. Loop unrolled. */
+    R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
+    R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
+    R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
+    R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
+    R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
+    R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
+    R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
+    R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
+    R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
+    R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
+    R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
+    R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
+    R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
+    R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
+    R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
+    R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
+    R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
+    R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
+    R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
+    R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
+#endif
+
+    /* Add the working vars back into context.state[] */
+    state[0] += a;
+    state[1] += b;
+    state[2] += c;
+    state[3] += d;
+    state[4] += e;
+
+    /* Wipe variables */
+    a = b = c = d = e = 0;
+}
+
+
+/*
+ * SHA1Init - Initialize new context
+ */
+void SHA1Init(context)
+    SHA1_CTX *context;
+{
+
+    _DIAGASSERT(context != 0);
+
+    /* SHA1 initialization constants */
+    context->state[0] = 0x67452301;
+    context->state[1] = 0xEFCDAB89;
+    context->state[2] = 0x98BADCFE;
+    context->state[3] = 0x10325476;
+    context->state[4] = 0xC3D2E1F0;
+    context->count[0] = context->count[1] = 0;
+}
+
+
+/*
+ * Run your data through this.
+ */
+void SHA1Update(context, data, len)
+    SHA1_CTX *context;
+    const unsigned char *data;
+    unsigned int len;
+{
+    unsigned int i, j;
+
+    _DIAGASSERT(context != 0);
+    _DIAGASSERT(data != 0);
+
+    j = context->count[0];
+    if ((context->count[0] += len << 3) < j)
+       context->count[1] += (len>>29)+1;
+    j = (j >> 3) & 63;
+    if ((j + len) > 63) {
+       (void)memcpy(&context->buffer[j], data, (i = 64-j));
+       SHA1Transform(context->state, context->buffer);
+       for ( ; i + 63 < len; i += 64)
+           SHA1Transform(context->state, &data[i]);
+       j = 0;
+    } else {
+       i = 0;
+    }
+    (void)memcpy(&context->buffer[j], &data[i], len - i);
+}
+
+
+/*
+ * Add padding and return the message digest.
+ */
+void SHA1Final(digest, context)
+    unsigned char digest[20];
+    SHA1_CTX* context;
+{
+    unsigned int i;
+    unsigned char finalcount[8];
+
+    _DIAGASSERT(digest != 0);
+    _DIAGASSERT(context != 0);
+
+    for (i = 0; i < 8; i++) {
+       finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
+        >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
+    }
+    SHA1Update(context, (unsigned char *)"\200", 1);
+    while ((context->count[0] & 504) != 448)
+       SHA1Update(context, (unsigned char *)"\0", 1);
+    SHA1Update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
+
+    if (digest) {
+       for (i = 0; i < 20; i++)
+           digest[i] = (unsigned char)
+               ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
+    }
+}
+

diff --git a/lib/libutil/sha1hl.c b/lib/libutil/sha1hl.c
new file mode 100644 (file)
index 0000000..47c5db1
--- /dev/null
+++ b/lib/libutil/sha1hl.c
@@ -0,0 +1,113 @@
+/*     $NetBSD: sha1hl.c,v 1.8 2008/10/06 12:36:20 joerg Exp $ */
+
+/* sha1hl.c
+ * ----------------------------------------------------------------------------
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * <phk@login.dkuug.dk> wrote this file.  As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
+ * ----------------------------------------------------------------------------
+ */
+
+#if 0
+#include "namespace.h"
+#endif
+
+#include <sys/cdefs.h>
+#include <sys/file.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <minix/sha1.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define _DIAGASSERT assert
+
+#if HAVE_NBTOOL_CONFIG_H
+#include "nbtool_config.h"
+#endif
+
+#if defined(LIBC_SCCS) && !defined(lint)
+__RCSID("$NetBSD: sha1hl.c,v 1.8 2008/10/06 12:36:20 joerg Exp $");
+#endif /* LIBC_SCCS and not lint */
+
+#if 0
+#if defined(__weak_alias)
+__weak_alias(SHA1End,_SHA1End)
+__weak_alias(SHA1File,_SHA1File)
+__weak_alias(SHA1Data,_SHA1Data)
+#endif
+#endif
+
+/* ARGSUSED */
+char *
+SHA1End(ctx, buf)
+    SHA1_CTX *ctx;
+    char *buf;
+{
+    int i;
+    char *p = buf;
+    unsigned char digest[20];
+    static const char hex[]="0123456789abcdef";
+
+    _DIAGASSERT(ctx != NULL);
+    /* buf may be NULL */
+
+    if (p == NULL && (p = malloc(41)) == NULL)
+       return 0;
+
+    SHA1Final(digest,ctx);
+    for (i = 0; i < 20; i++) {
+       p[i + i] = hex[((uint32_t)digest[i]) >> 4];
+       p[i + i + 1] = hex[digest[i] & 0x0f];
+    }
+    p[i + i] = '\0';
+    return(p);
+}
+
+char *
+SHA1File (filename, buf)
+    char *filename;
+    char *buf;
+{
+    unsigned char buffer[BUFSIZ];
+    SHA1_CTX ctx;
+    int fd, num, oerrno;
+
+    _DIAGASSERT(filename != NULL);
+    /* XXX: buf may be NULL ? */
+
+    SHA1Init(&ctx);
+
+    if ((fd = open(filename,O_RDONLY)) < 0)
+       return(0);
+
+    while ((num = read(fd, buffer, sizeof(buffer))) > 0)
+       SHA1Update(&ctx, buffer, (size_t)num);
+
+    oerrno = errno;
+    close(fd);
+    errno = oerrno;
+    return(num < 0 ? 0 : SHA1End(&ctx, buf));
+}
+
+char *
+SHA1Data (data, len, buf)
+    const unsigned char *data;
+    size_t len;
+    char *buf;
+{
+    SHA1_CTX ctx;
+
+    _DIAGASSERT(data != NULL);
+    /* XXX: buf may be NULL ? */
+
+    SHA1Init(&ctx);
+    SHA1Update(&ctx, data, len);
+    return(SHA1End(&ctx, buf));
+}

diff --git a/man/man3/sha1.3 b/man/man3/sha1.3
new file mode 100644 (file)
index 0000000..13ae148
--- /dev/null
+++ b/man/man3/sha1.3
@@ -0,0 +1,193 @@
+.\"    $OpenBSD: sha1.3,v 1.37 2008/02/13 08:43:39 art Exp $
+.\"
+.\" Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller@courtesan.com>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.\" See http://csrc.nist.gov/publications/fips/fips180-1/fip180-1.txt
+.\" for the detailed standard
+.\"
+.Dd $Mdocdate: February 13 2008 $
+.Dt SHA1 3
+.Os
+.Sh NAME
+.Nm SHA1Init ,
+.Nm SHA1Update ,
+.Nm SHA1Final ,
+.Nm SHA1Transform ,
+.Nm SHA1End ,
+.Nm SHA1File ,
+.Nm SHA1Data
+.Nd calculate the NIST Secure Hash Algorithm
+.Sh SYNOPSIS
+.Fd #include <sys/types.h>
+.Fd #include <sha1.h>
+.Ft void
+.Fn SHA1Init "SHA1_CTX *context"
+.Ft void
+.Fn SHA1Update "SHA1_CTX *context" "const u_int8_t *data" "size_t len"
+.Ft void
+.Fn SHA1Final "u_int8_t digest[SHA1_DIGEST_LENGTH]" "SHA1_CTX *context"
+.Ft void
+.Fn SHA1Transform "u_int32_t state[5]" "const u_int8_t buffer[SHA1_BLOCK_LENGTH]"
+.Ft "char *"
+.Fn SHA1End "SHA1_CTX *context" "char *buf"
+.Ft "char *"
+.Fn SHA1File "const char *filename" "char *buf"
+.Ft "char *"
+.Fn SHA1Data "const u_int8_t *data" "size_t len" "char *buf"
+.Sh DESCRIPTION
+The SHA1 functions implement the NIST Secure Hash Algorithm (SHA-1),
+FIPS PUB 180-1.
+SHA-1 is used to generate a condensed representation
+of a message called a message digest.
+The algorithm takes a
+message less than 2^64 bits as input and produces a 160-bit digest
+suitable for use as a digital signature.
+.Pp
+The SHA1 functions are considered to be more secure than the
+.Xr md4 3
+and
+.Xr md5 3
+functions with which they share a similar interface.
+.Pp
+The
+.Fn SHA1Init
+function initializes a SHA1_CTX
+.Ar context
+for use with
+.Fn SHA1Update ,
+and
+.Fn SHA1Final .
+The
+.Fn SHA1Update
+function adds
+.Ar data
+of length
+.Ar len
+to the SHA1_CTX specified by
+.Ar context .
+.Fn SHA1Final
+is called when all data has been added via
+.Fn SHA1Update
+and stores a message digest in the
+.Ar digest
+parameter.
+.Pp
+The
+.Fn SHA1Transform
+function is used by
+.Fn SHA1Update
+to hash 512-bit blocks and forms the core of the algorithm.
+Most programs should use the interface provided by
+.Fn SHA1Init ,
+.Fn SHA1Update
+and
+.Fn SHA1Final
+instead of calling
+.Fn SHA1Transform
+directly.
+.Pp
+The
+.Fn SHA1End
+function is a front end for
+.Fn SHA1Final
+which converts the digest into an
+.Tn ASCII
+representation of the 160 bit digest in hexadecimal.
+.Pp
+The
+.Fn SHA1File
+function calculates the digest for a file and returns the result via
+.Fn SHA1End .
+If
+.Fn SHA1File
+is unable to open the file a NULL pointer is returned.
+.Pp
+The
+.Fn SHA1Data
+function
+calculates the digest of an arbitrary string and returns the result via
+.Fn SHA1End .
+.Pp
+For each of the
+.Fn SHA1End ,
+.Fn SHA1File ,
+and
+.Fn SHA1Data
+functions the
+.Ar buf
+parameter should either be a string of at least 41 characters in
+size or a NULL pointer.
+In the latter case, space will be dynamically allocated via
+.Xr malloc 3
+and should be freed using
+.Xr free 3
+when it is no longer needed.
+.Sh EXAMPLES
+The follow code fragment will calculate the digest for
+the string "abc" which is ``0xa9993e364706816aba3e25717850c26c9cd0d89d''.
+.Bd -literal -offset indent
+SHA1_CTX sha;
+u_int8_t results[SHA1_DIGEST_LENGTH];
+char *buf;
+int n;
+
+buf = "abc";
+n = strlen(buf);
+SHA1Init(&sha);
+SHA1Update(&sha, (u_int8_t *)buf, n);
+SHA1Final(results, &sha);
+
+/* Print the digest as one long hex value */
+printf("0x");
+for (n = 0; n < SHA1_DIGEST_LENGTH; n++)
+       printf("%02x", results[n]);
+putchar('\en');
+.Ed
+.Pp
+Alternately, the helper functions could be used in the following way:
+.Bd -literal -offset indent
+u_int8_t output[SHA1_DIGEST_STRING_LENGTH];
+char *buf = "abc";
+
+printf("0x%s\en", SHA1Data(buf, strlen(buf), output));
+.Ed
+.Sh SEE ALSO
+.Xr cksum 1 ,
+.Xr sha1 1 ,
+.Xr md4 3 ,
+.Xr md5 3 ,
+.Xr rmd160 3 ,
+.Xr sha2 3
+.Rs
+.%A J. Burrows
+.%T The Secure Hash Standard
+.%O FIPS PUB 180-1
+.Re
+.Rs
+.%A D. Eastlake and P. Jones
+.%T US Secure Hash Algorithm 1
+.%O RFC 3174
+.Re
+.Sh HISTORY
+The SHA-1 functions appeared in
+.Ox 2.0 .
+.Sh CAVEATS
+This implementation of SHA-1 has not been validated by NIST
+and as such is not in official compliance with the standard.
+.Pp
+If a message digest is to be copied to a multi-byte type (ie:
+an array of five 32-bit integers) it will be necessary to
+perform byte swapping on little endian machines such as the i386, alpha,
+and vax.