diff options
Diffstat (limited to 'tools/plink/sshmd5.c')
| -rw-r--r-- | tools/plink/sshmd5.c | 344 | 
1 files changed, 344 insertions, 0 deletions
| diff --git a/tools/plink/sshmd5.c b/tools/plink/sshmd5.c new file mode 100644 index 000000000..80474dfad --- /dev/null +++ b/tools/plink/sshmd5.c @@ -0,0 +1,344 @@ +#include "ssh.h"
 +
 +/*
 + * MD5 implementation for PuTTY. Written directly from the spec by
 + * Simon Tatham.
 + */
 +
 +/* ----------------------------------------------------------------------
 + * Core MD5 algorithm: processes 16-word blocks into a message digest.
 + */
 +
 +#define F(x,y,z) ( ((x) & (y)) | ((~(x)) & (z)) )
 +#define G(x,y,z) ( ((x) & (z)) | ((~(z)) & (y)) )
 +#define H(x,y,z) ( (x) ^ (y) ^ (z) )
 +#define I(x,y,z) ( (y) ^ ( (x) | ~(z) ) )
 +
 +#define rol(x,y) ( ((x) << (y)) | (((uint32)x) >> (32-y)) )
 +
 +#define subround(f,w,x,y,z,k,s,ti) \
 +       w = x + rol(w + f(x,y,z) + block[k] + ti, s)
 +
 +static void MD5_Core_Init(MD5_Core_State * s)
 +{
 +    s->h[0] = 0x67452301;
 +    s->h[1] = 0xefcdab89;
 +    s->h[2] = 0x98badcfe;
 +    s->h[3] = 0x10325476;
 +}
 +
 +static void MD5_Block(MD5_Core_State * s, uint32 * block)
 +{
 +    uint32 a, b, c, d;
 +
 +    a = s->h[0];
 +    b = s->h[1];
 +    c = s->h[2];
 +    d = s->h[3];
 +
 +    subround(F, a, b, c, d, 0, 7, 0xd76aa478);
 +    subround(F, d, a, b, c, 1, 12, 0xe8c7b756);
 +    subround(F, c, d, a, b, 2, 17, 0x242070db);
 +    subround(F, b, c, d, a, 3, 22, 0xc1bdceee);
 +    subround(F, a, b, c, d, 4, 7, 0xf57c0faf);
 +    subround(F, d, a, b, c, 5, 12, 0x4787c62a);
 +    subround(F, c, d, a, b, 6, 17, 0xa8304613);
 +    subround(F, b, c, d, a, 7, 22, 0xfd469501);
 +    subround(F, a, b, c, d, 8, 7, 0x698098d8);
 +    subround(F, d, a, b, c, 9, 12, 0x8b44f7af);
 +    subround(F, c, d, a, b, 10, 17, 0xffff5bb1);
 +    subround(F, b, c, d, a, 11, 22, 0x895cd7be);
 +    subround(F, a, b, c, d, 12, 7, 0x6b901122);
 +    subround(F, d, a, b, c, 13, 12, 0xfd987193);
 +    subround(F, c, d, a, b, 14, 17, 0xa679438e);
 +    subround(F, b, c, d, a, 15, 22, 0x49b40821);
 +    subround(G, a, b, c, d, 1, 5, 0xf61e2562);
 +    subround(G, d, a, b, c, 6, 9, 0xc040b340);
 +    subround(G, c, d, a, b, 11, 14, 0x265e5a51);
 +    subround(G, b, c, d, a, 0, 20, 0xe9b6c7aa);
 +    subround(G, a, b, c, d, 5, 5, 0xd62f105d);
 +    subround(G, d, a, b, c, 10, 9, 0x02441453);
 +    subround(G, c, d, a, b, 15, 14, 0xd8a1e681);
 +    subround(G, b, c, d, a, 4, 20, 0xe7d3fbc8);
 +    subround(G, a, b, c, d, 9, 5, 0x21e1cde6);
 +    subround(G, d, a, b, c, 14, 9, 0xc33707d6);
 +    subround(G, c, d, a, b, 3, 14, 0xf4d50d87);
 +    subround(G, b, c, d, a, 8, 20, 0x455a14ed);
 +    subround(G, a, b, c, d, 13, 5, 0xa9e3e905);
 +    subround(G, d, a, b, c, 2, 9, 0xfcefa3f8);
 +    subround(G, c, d, a, b, 7, 14, 0x676f02d9);
 +    subround(G, b, c, d, a, 12, 20, 0x8d2a4c8a);
 +    subround(H, a, b, c, d, 5, 4, 0xfffa3942);
 +    subround(H, d, a, b, c, 8, 11, 0x8771f681);
 +    subround(H, c, d, a, b, 11, 16, 0x6d9d6122);
 +    subround(H, b, c, d, a, 14, 23, 0xfde5380c);
 +    subround(H, a, b, c, d, 1, 4, 0xa4beea44);
 +    subround(H, d, a, b, c, 4, 11, 0x4bdecfa9);
 +    subround(H, c, d, a, b, 7, 16, 0xf6bb4b60);
 +    subround(H, b, c, d, a, 10, 23, 0xbebfbc70);
 +    subround(H, a, b, c, d, 13, 4, 0x289b7ec6);
 +    subround(H, d, a, b, c, 0, 11, 0xeaa127fa);
 +    subround(H, c, d, a, b, 3, 16, 0xd4ef3085);
 +    subround(H, b, c, d, a, 6, 23, 0x04881d05);
 +    subround(H, a, b, c, d, 9, 4, 0xd9d4d039);
 +    subround(H, d, a, b, c, 12, 11, 0xe6db99e5);
 +    subround(H, c, d, a, b, 15, 16, 0x1fa27cf8);
 +    subround(H, b, c, d, a, 2, 23, 0xc4ac5665);
 +    subround(I, a, b, c, d, 0, 6, 0xf4292244);
 +    subround(I, d, a, b, c, 7, 10, 0x432aff97);
 +    subround(I, c, d, a, b, 14, 15, 0xab9423a7);
 +    subround(I, b, c, d, a, 5, 21, 0xfc93a039);
 +    subround(I, a, b, c, d, 12, 6, 0x655b59c3);
 +    subround(I, d, a, b, c, 3, 10, 0x8f0ccc92);
 +    subround(I, c, d, a, b, 10, 15, 0xffeff47d);
 +    subround(I, b, c, d, a, 1, 21, 0x85845dd1);
 +    subround(I, a, b, c, d, 8, 6, 0x6fa87e4f);
 +    subround(I, d, a, b, c, 15, 10, 0xfe2ce6e0);
 +    subround(I, c, d, a, b, 6, 15, 0xa3014314);
 +    subround(I, b, c, d, a, 13, 21, 0x4e0811a1);
 +    subround(I, a, b, c, d, 4, 6, 0xf7537e82);
 +    subround(I, d, a, b, c, 11, 10, 0xbd3af235);
 +    subround(I, c, d, a, b, 2, 15, 0x2ad7d2bb);
 +    subround(I, b, c, d, a, 9, 21, 0xeb86d391);
 +
 +    s->h[0] += a;
 +    s->h[1] += b;
 +    s->h[2] += c;
 +    s->h[3] += d;
 +}
 +
 +/* ----------------------------------------------------------------------
 + * Outer MD5 algorithm: take an arbitrary length byte string,
 + * convert it into 16-word blocks with the prescribed padding at
 + * the end, and pass those blocks to the core MD5 algorithm.
 + */
 +
 +#define BLKSIZE 64
 +
 +void MD5Init(struct MD5Context *s)
 +{
 +    MD5_Core_Init(&s->core);
 +    s->blkused = 0;
 +    s->lenhi = s->lenlo = 0;
 +}
 +
 +void MD5Update(struct MD5Context *s, unsigned char const *p, unsigned len)
 +{
 +    unsigned char *q = (unsigned char *) p;
 +    uint32 wordblock[16];
 +    uint32 lenw = len;
 +    int i;
 +
 +    /*
 +     * Update the length field.
 +     */
 +    s->lenlo += lenw;
 +    s->lenhi += (s->lenlo < lenw);
 +
 +    if (s->blkused + len < BLKSIZE) {
 +	/*
 +	 * Trivial case: just add to the block.
 +	 */
 +	memcpy(s->block + s->blkused, q, len);
 +	s->blkused += len;
 +    } else {
 +	/*
 +	 * We must complete and process at least one block.
 +	 */
 +	while (s->blkused + len >= BLKSIZE) {
 +	    memcpy(s->block + s->blkused, q, BLKSIZE - s->blkused);
 +	    q += BLKSIZE - s->blkused;
 +	    len -= BLKSIZE - s->blkused;
 +	    /* Now process the block. Gather bytes little-endian into words */
 +	    for (i = 0; i < 16; i++) {
 +		wordblock[i] =
 +		    (((uint32) s->block[i * 4 + 3]) << 24) |
 +		    (((uint32) s->block[i * 4 + 2]) << 16) |
 +		    (((uint32) s->block[i * 4 + 1]) << 8) |
 +		    (((uint32) s->block[i * 4 + 0]) << 0);
 +	    }
 +	    MD5_Block(&s->core, wordblock);
 +	    s->blkused = 0;
 +	}
 +	memcpy(s->block, q, len);
 +	s->blkused = len;
 +    }
 +}
 +
 +void MD5Final(unsigned char output[16], struct MD5Context *s)
 +{
 +    int i;
 +    unsigned pad;
 +    unsigned char c[64];
 +    uint32 lenhi, lenlo;
 +
 +    if (s->blkused >= 56)
 +	pad = 56 + 64 - s->blkused;
 +    else
 +	pad = 56 - s->blkused;
 +
 +    lenhi = (s->lenhi << 3) | (s->lenlo >> (32 - 3));
 +    lenlo = (s->lenlo << 3);
 +
 +    memset(c, 0, pad);
 +    c[0] = 0x80;
 +    MD5Update(s, c, pad);
 +
 +    c[7] = (lenhi >> 24) & 0xFF;
 +    c[6] = (lenhi >> 16) & 0xFF;
 +    c[5] = (lenhi >> 8) & 0xFF;
 +    c[4] = (lenhi >> 0) & 0xFF;
 +    c[3] = (lenlo >> 24) & 0xFF;
 +    c[2] = (lenlo >> 16) & 0xFF;
 +    c[1] = (lenlo >> 8) & 0xFF;
 +    c[0] = (lenlo >> 0) & 0xFF;
 +
 +    MD5Update(s, c, 8);
 +
 +    for (i = 0; i < 4; i++) {
 +	output[4 * i + 3] = (s->core.h[i] >> 24) & 0xFF;
 +	output[4 * i + 2] = (s->core.h[i] >> 16) & 0xFF;
 +	output[4 * i + 1] = (s->core.h[i] >> 8) & 0xFF;
 +	output[4 * i + 0] = (s->core.h[i] >> 0) & 0xFF;
 +    }
 +}
 +
 +void MD5Simple(void const *p, unsigned len, unsigned char output[16])
 +{
 +    struct MD5Context s;
 +
 +    MD5Init(&s);
 +    MD5Update(&s, (unsigned char const *)p, len);
 +    MD5Final(output, &s);
 +}
 +
 +/* ----------------------------------------------------------------------
 + * The above is the MD5 algorithm itself. Now we implement the
 + * HMAC wrapper on it.
 + * 
 + * Some of these functions are exported directly, because they are
 + * useful elsewhere (SOCKS5 CHAP authentication uses HMAC-MD5).
 + */
 +
 +void *hmacmd5_make_context(void)
 +{
 +    return snewn(3, struct MD5Context);
 +}
 +
 +void hmacmd5_free_context(void *handle)
 +{
 +    sfree(handle);
 +}
 +
 +void hmacmd5_key(void *handle, void const *keyv, int len)
 +{
 +    struct MD5Context *keys = (struct MD5Context *)handle;
 +    unsigned char foo[64];
 +    unsigned char const *key = (unsigned char const *)keyv;
 +    int i;
 +
 +    memset(foo, 0x36, 64);
 +    for (i = 0; i < len && i < 64; i++)
 +	foo[i] ^= key[i];
 +    MD5Init(&keys[0]);
 +    MD5Update(&keys[0], foo, 64);
 +
 +    memset(foo, 0x5C, 64);
 +    for (i = 0; i < len && i < 64; i++)
 +	foo[i] ^= key[i];
 +    MD5Init(&keys[1]);
 +    MD5Update(&keys[1], foo, 64);
 +
 +    memset(foo, 0, 64);		       /* burn the evidence */
 +}
 +
 +static void hmacmd5_key_16(void *handle, unsigned char *key)
 +{
 +    hmacmd5_key(handle, key, 16);
 +}
 +
 +static void hmacmd5_start(void *handle)
 +{
 +    struct MD5Context *keys = (struct MD5Context *)handle;
 +
 +    keys[2] = keys[0];		      /* structure copy */
 +}
 +
 +static void hmacmd5_bytes(void *handle, unsigned char const *blk, int len)
 +{
 +    struct MD5Context *keys = (struct MD5Context *)handle;
 +    MD5Update(&keys[2], blk, len);
 +}
 +
 +static void hmacmd5_genresult(void *handle, unsigned char *hmac)
 +{
 +    struct MD5Context *keys = (struct MD5Context *)handle;
 +    struct MD5Context s;
 +    unsigned char intermediate[16];
 +
 +    s = keys[2];		       /* structure copy */
 +    MD5Final(intermediate, &s);
 +    s = keys[1];		       /* structure copy */
 +    MD5Update(&s, intermediate, 16);
 +    MD5Final(hmac, &s);
 +}
 +
 +static int hmacmd5_verresult(void *handle, unsigned char const *hmac)
 +{
 +    unsigned char correct[16];
 +    hmacmd5_genresult(handle, correct);
 +    return !memcmp(correct, hmac, 16);
 +}
 +
 +static void hmacmd5_do_hmac_internal(void *handle,
 +				     unsigned char const *blk, int len,
 +				     unsigned char const *blk2, int len2,
 +				     unsigned char *hmac)
 +{
 +    hmacmd5_start(handle);
 +    hmacmd5_bytes(handle, blk, len);
 +    if (blk2) hmacmd5_bytes(handle, blk2, len2);
 +    hmacmd5_genresult(handle, hmac);
 +}
 +
 +void hmacmd5_do_hmac(void *handle, unsigned char const *blk, int len,
 +		     unsigned char *hmac)
 +{
 +    hmacmd5_do_hmac_internal(handle, blk, len, NULL, 0, hmac);
 +}
 +
 +static void hmacmd5_do_hmac_ssh(void *handle, unsigned char const *blk, int len,
 +				unsigned long seq, unsigned char *hmac)
 +{
 +    unsigned char seqbuf[16];
 +
 +    seqbuf[0] = (unsigned char) ((seq >> 24) & 0xFF);
 +    seqbuf[1] = (unsigned char) ((seq >> 16) & 0xFF);
 +    seqbuf[2] = (unsigned char) ((seq >> 8) & 0xFF);
 +    seqbuf[3] = (unsigned char) ((seq) & 0xFF);
 +
 +    hmacmd5_do_hmac_internal(handle, seqbuf, 4, blk, len, hmac);
 +}
 +
 +static void hmacmd5_generate(void *handle, unsigned char *blk, int len,
 +			     unsigned long seq)
 +{
 +    hmacmd5_do_hmac_ssh(handle, blk, len, seq, blk + len);
 +}
 +
 +static int hmacmd5_verify(void *handle, unsigned char *blk, int len,
 +			  unsigned long seq)
 +{
 +    unsigned char correct[16];
 +    hmacmd5_do_hmac_ssh(handle, blk, len, seq, correct);
 +    return !memcmp(correct, blk + len, 16);
 +}
 +
 +const struct ssh_mac ssh_hmac_md5 = {
 +    hmacmd5_make_context, hmacmd5_free_context, hmacmd5_key_16,
 +    hmacmd5_generate, hmacmd5_verify,
 +    hmacmd5_start, hmacmd5_bytes, hmacmd5_genresult, hmacmd5_verresult,
 +    "hmac-md5",
 +    16,
 +    "HMAC-MD5"
 +};
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