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📄 ssh2.c

📁 老外写的加密库cryptlib(版本3.1)
💻 C
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/****************************************************************************
*																			*
*						cryptlib SSHv2 Session Management					*
*						Copyright Peter Gutmann 1998-2003					*
*																			*
****************************************************************************/

#include <stdlib.h>
#include <string.h>
#if defined( INC_ALL )
  #include "crypt.h"
  #include "session.h"
  #include "ssh.h"
#elif defined( INC_CHILD )
  #include "../crypt.h"
  #include "../session/session.h"
  #include "../session/ssh.h"
#else
  #include "crypt.h"
  #include "session/session.h"
  #include "session/ssh.h"
#endif /* Compiler-specific includes */

#ifdef USE_SSH2

/* Tables mapping SSHv2 algorithm names to cryptlib algorithm IDs, in 
   preferred algorithm order.  See the comment in ssh2_svr.c for the reason
   behind the difference in encryption algorithm tables for client and 
   server */

static const FAR_BSS ALGO_STRING_INFO algoStringKeyexTbl[] = {
	{ "diffie-hellman-group-exchange-sha1", CRYPT_ALGO_DES },	/* Placeholder algo ID */
	{ "diffie-hellman-group1-sha1", CRYPT_ALGO_DH },
	{ NULL, CRYPT_ALGO_NONE }
	};

static const FAR_BSS ALGO_STRING_INFO algoStringCoprTbl[] = {
	{ "none", CRYPT_ALGO_DES },		/* Placeholder algo ID */
	{ NULL, CRYPT_ALGO_NONE }
	};

static const FAR_BSS ALGO_STRING_INFO algoStringPubkeyTbl[] = {
	{ "ssh-rsa", CRYPT_ALGO_RSA },
	{ "ssh-dss", CRYPT_ALGO_DSA },
	{ NULL, CRYPT_ALGO_NONE }
	};

static const FAR_BSS ALGO_STRING_INFO algoStringEncrTblClient[] = {
	{ "3des-cbc", CRYPT_ALGO_3DES },
	{ "aes128-cbc", CRYPT_ALGO_AES },
	{ "blowfish-cbc", CRYPT_ALGO_BLOWFISH },
	{ "cast128-cbc", CRYPT_ALGO_CAST },
	{ "idea-cbc", CRYPT_ALGO_IDEA },
	{ "arcfour", CRYPT_ALGO_RC4 },
	{ NULL, CRYPT_ALGO_NONE }
	};
static const FAR_BSS ALGO_STRING_INFO algoStringEncrTblServer[] = {
	{ "3des-cbc", CRYPT_ALGO_3DES },
	{ "blowfish-cbc", CRYPT_ALGO_BLOWFISH },
	{ "cast128-cbc", CRYPT_ALGO_CAST },
	{ "idea-cbc", CRYPT_ALGO_IDEA },
	{ "arcfour", CRYPT_ALGO_RC4 },
	{ NULL, CRYPT_ALGO_NONE }
	};

static const FAR_BSS ALGO_STRING_INFO algoStringMACTbl[] = {
	{ "hmac-sha1", CRYPT_ALGO_HMAC_SHA },
	{ "hmac-md5", CRYPT_ALGO_HMAC_MD5 },
	{ NULL, CRYPT_ALGO_NONE }
	};

static const FAR_BSS ALGO_STRING_INFO algoStringUserauthentTbl[] = {
	{ "password", CRYPT_ALGO_DES },		/* Placeholder algo ID */
	{ "publickey", CRYPT_ALGO_RSA },
	{ NULL, CRYPT_ALGO_NONE }
	};

/****************************************************************************
*																			*
*								Utility Functions							*
*																			*
****************************************************************************/

/* Load the fixed SSHv2 DH key into a context.  The prime is the value
   2^1024 - 2^960 - 1 + 2^64 * { [2^894 pi] + 129093 }, from the Oakley spec
   (RFC 2412, other locations omit the q value).  Unfortunately the choice 
   of q leads to horribly inefficient operations since it's 860 bits larger 
   than it needs to be */

static const FAR_BSS BYTE dh1024SPKI[] = {
	0x30, 0x82, 0x01, 0x21,
		0x30, 0x82, 0x01, 0x17,
			0x06, 0x07, 0x2A, 0x86, 0x48, 0xCE, 0x3E, 0x02, 0x01,
			0x30, 0x82, 0x01, 0x0A,
				0x02, 0x81, 0x81, 0x00,		/* p */
					0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
					0xC9, 0x0F, 0xDA, 0xA2, 0x21, 0x68, 0xC2, 0x34,
					0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
					0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74,
					0x02, 0x0B, 0xBE, 0xA6, 0x3B, 0x13, 0x9B, 0x22,
					0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
					0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B,
					0x30, 0x2B, 0x0A, 0x6D, 0xF2, 0x5F, 0x14, 0x37,
					0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
					0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6,
					0xF4, 0x4C, 0x42, 0xE9, 0xA6, 0x37, 0xED, 0x6B,
					0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
					0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5,
					0xAE, 0x9F, 0x24, 0x11, 0x7C, 0x4B, 0x1F, 0xE6,
					0x49, 0x28, 0x66, 0x51, 0xEC, 0xE6, 0x53, 0x81,
					0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
				0x02, 0x01,					/* g */
					0x02,
				0x02, 0x81, 0x80,			/* q */
					0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
					0xE4, 0x87, 0xED, 0x51, 0x10, 0xB4, 0x61, 0x1A,
					0x62, 0x63, 0x31, 0x45, 0xC0, 0x6E, 0x0E, 0x68,
					0x94, 0x81, 0x27, 0x04, 0x45, 0x33, 0xE6, 0x3A,
					0x01, 0x05, 0xDF, 0x53, 0x1D, 0x89, 0xCD, 0x91,
					0x28, 0xA5, 0x04, 0x3C, 0xC7, 0x1A, 0x02, 0x6E,
					0xF7, 0xCA, 0x8C, 0xD9, 0xE6, 0x9D, 0x21, 0x8D,
					0x98, 0x15, 0x85, 0x36, 0xF9, 0x2F, 0x8A, 0x1B,
					0xA7, 0xF0, 0x9A, 0xB6, 0xB6, 0xA8, 0xE1, 0x22,
					0xF2, 0x42, 0xDA, 0xBB, 0x31, 0x2F, 0x3F, 0x63,
					0x7A, 0x26, 0x21, 0x74, 0xD3, 0x1B, 0xF6, 0xB5,
					0x85, 0xFF, 0xAE, 0x5B, 0x7A, 0x03, 0x5B, 0xF6,
					0xF7, 0x1C, 0x35, 0xFD, 0xAD, 0x44, 0xCF, 0xD2,
					0xD7, 0x4F, 0x92, 0x08, 0xBE, 0x25, 0x8F, 0xF3,
					0x24, 0x94, 0x33, 0x28, 0xF6, 0x73, 0x29, 0xC0,
					0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
		0x03, 0x04, 0x00,
			0x02, 0x01, 0x00 };				/* y */

/* Additional DH values, from RFC 3526.  The 1536-bit value is widely used 
   in IKE, and has the prime value 
   2^1536 - 2^1472 - 1 + 2^64 * { [2^1406 pi] + 741804 }.  The 2048-bit
   value has the prime value 
   2^2048 - 2^1984 - 1 + 2^64 * { [2^1918 pi] + 124476 }, and the 3072-bit
   value has the prime value
   2^3072 - 2^3008 - 1 + 2^64 * { [2^2942 pi] + 1690314 }.  All have a 
   generator of 2 */

static const FAR_BSS BYTE dh1536SSH[] = {
	0x00, 0x00, 0x00, 0xD8,
		0x00, 0x00, 0x00, 0x06,		/* Algorithm ID */
			's', 's', 'h', '-', 'd', 'h',
		0x00, 0x00, 0x00, 0xC1,		/* p */
			0x00,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
			0xC9, 0x0F, 0xDA, 0xA2, 0x21, 0x68, 0xC2, 0x34, 
			0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
			0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 
			0x02, 0x0B, 0xBE, 0xA6, 0x3B, 0x13, 0x9B, 0x22, 
			0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
			0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 
			0x30, 0x2B, 0x0A, 0x6D, 0xF2, 0x5F, 0x14, 0x37, 
			0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
			0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 
			0xF4, 0x4C, 0x42, 0xE9, 0xA6, 0x37, 0xED, 0x6B, 
			0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
			0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 
			0xAE, 0x9F, 0x24, 0x11, 0x7C, 0x4B, 0x1F, 0xE6, 
			0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D,
			0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 
			0x98, 0xDA, 0x48, 0x36, 0x1C, 0x55, 0xD3, 0x9A, 
			0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F,
			0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 
			0x1C, 0x62, 0xF3, 0x56, 0x20, 0x85, 0x52, 0xBB, 
			0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D,
			0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 
			0xF1, 0x74, 0x6C, 0x08, 0xCA, 0x23, 0x73, 0x27, 
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x01,		/* g */
			0x02
	};

static const FAR_BSS BYTE dh2048SSH[] = {
	0x00, 0x00, 0x01, 0x18,
		0x00, 0x00, 0x00, 0x06,		/* Algorithm ID */
			's', 's', 'h', '-', 'd', 'h',
		0x00, 0x00, 0x01, 0x01,		/* p */
			0x00,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
			0xC9, 0x0F, 0xDA, 0xA2, 0x21, 0x68, 0xC2, 0x34, 
			0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
			0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 
			0x02, 0x0B, 0xBE, 0xA6, 0x3B, 0x13, 0x9B, 0x22, 
			0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
			0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 
			0x30, 0x2B, 0x0A, 0x6D, 0xF2, 0x5F, 0x14, 0x37, 
			0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
			0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 
			0xF4, 0x4C, 0x42, 0xE9, 0xA6, 0x37, 0xED, 0x6B, 
			0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
			0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 
			0xAE, 0x9F, 0x24, 0x11, 0x7C, 0x4B, 0x1F, 0xE6, 
			0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D,
			0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 
			0x98, 0xDA, 0x48, 0x36, 0x1C, 0x55, 0xD3, 0x9A, 
			0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F,
			0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 
			0x1C, 0x62, 0xF3, 0x56, 0x20, 0x85, 0x52, 0xBB, 
			0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D,
			0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 
			0xF1, 0x74, 0x6C, 0x08, 0xCA, 0x18, 0x21, 0x7C, 
			0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B,
			0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 
			0x9B, 0x27, 0x83, 0xA2, 0xEC, 0x07, 0xA2, 0x8F, 
			0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9,
			0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 
			0x39, 0x95, 0x49, 0x7C, 0xEA, 0x95, 0x6A, 0xE5, 
			0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10,
			0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAC, 0xAA, 0x68, 
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x01,		/* g */
			0x02
	};

static const FAR_BSS BYTE dh3072SSH[] = {
	0x00, 0x00, 0x01, 0x98,
		0x00, 0x00, 0x00, 0x06,		/* Algorithm ID */
			's', 's', 'h', '-', 'd', 'h',
		0x00, 0x00, 0x01, 0x81,		/* p */
			0x00,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
			0xC9, 0x0F, 0xDA, 0xA2, 0x21, 0x68, 0xC2, 0x34, 
			0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
			0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 
			0x02, 0x0B, 0xBE, 0xA6, 0x3B, 0x13, 0x9B, 0x22, 
			0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
			0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 
			0x30, 0x2B, 0x0A, 0x6D, 0xF2, 0x5F, 0x14, 0x37, 
			0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
			0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 
			0xF4, 0x4C, 0x42, 0xE9, 0xA6, 0x37, 0xED, 0x6B, 
			0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
			0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 
			0xAE, 0x9F, 0x24, 0x11, 0x7C, 0x4B, 0x1F, 0xE6, 
			0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D,
			0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 
			0x98, 0xDA, 0x48, 0x36, 0x1C, 0x55, 0xD3, 0x9A, 
			0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F,
			0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 
			0x1C, 0x62, 0xF3, 0x56, 0x20, 0x85, 0x52, 0xBB, 
			0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D,
			0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 
			0xF1, 0x74, 0x6C, 0x08, 0xCA, 0x18, 0x21, 0x7C, 
			0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B,
			0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 
			0x9B, 0x27, 0x83, 0xA2, 0xEC, 0x07, 0xA2, 0x8F, 
			0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9,
			0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 
			0x39, 0x95, 0x49, 0x7C, 0xEA, 0x95, 0x6A, 0xE5, 
			0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10,
			0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAA, 0xC4, 0x2D, 
			0xAD, 0x33, 0x17, 0x0D, 0x04, 0x50, 0x7A, 0x33, 
			0xA8, 0x55, 0x21, 0xAB, 0xDF, 0x1C, 0xBA, 0x64,
			0xEC, 0xFB, 0x85, 0x04, 0x58, 0xDB, 0xEF, 0x0A, 
			0x8A, 0xEA, 0x71, 0x57, 0x5D, 0x06, 0x0C, 0x7D, 
			0xB3, 0x97, 0x0F, 0x85, 0xA6, 0xE1, 0xE4, 0xC7,
			0xAB, 0xF5, 0xAE, 0x8C, 0xDB, 0x09, 0x33, 0xD7, 
			0x1E, 0x8C, 0x94, 0xE0, 0x4A, 0x25, 0x61, 0x9D, 
			0xCE, 0xE3, 0xD2, 0x26, 0x1A, 0xD2, 0xEE, 0x6B,
			0xF1, 0x2F, 0xFA, 0x06, 0xD9, 0x8A, 0x08, 0x64, 
			0xD8, 0x76, 0x02, 0x73, 0x3E, 0xC8, 0x6A, 0x64, 
			0x52, 0x1F, 0x2B, 0x18, 0x17, 0x7B, 0x20, 0x0C,
			0xBB, 0xE1, 0x17, 0x57, 0x7A, 0x61, 0x5D, 0x6C, 
			0x77, 0x09, 0x88, 0xC0, 0xBA, 0xD9, 0x46, 0xE2, 
			0x08, 0xE2, 0x4F, 0xA0, 0x74, 0xE5, 0xAB, 0x31,
			0x43, 0xDB, 0x5B, 0xFC, 0xE0, 0xFD, 0x10, 0x8E, 
			0x4B, 0x82, 0xD1, 0x20, 0xA9, 0x3A, 0xD2, 0xCA, 
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x01,		/* g */
			0x02
	};

int initDHcontext( CRYPT_CONTEXT *iCryptContext, int *keySize, 
				   const void *keyData, const int keyDataLength,
				   const int requestedKeySize )
	{
	MESSAGE_CREATEOBJECT_INFO createInfo;
	RESOURCE_DATA msgData;
	int length, status;

	assert( ( keyData != NULL && keyDataLength > 0 && \
			  isReadPtr( keyData, keyDataLength ) && \
			  requestedKeySize == CRYPT_UNUSED ) || \
			( keyData == NULL && keyDataLength == 0 && \
			  requestedKeySize == CRYPT_USE_DEFAULT ) || \
			( keyData == NULL && keyDataLength == 0 && \
			  requestedKeySize >= bitsToBytes( MIN_PKCSIZE_BITS ) && \
			  requestedKeySize <= CRYPT_MAX_PKCSIZE ) );

	*iCryptContext = CRYPT_ERROR;
	*keySize = 0;

	/* Create the DH context */
	setMessageCreateObjectInfo( &createInfo, CRYPT_ALGO_DH );
	status = krnlSendMessage( SYSTEM_OBJECT_HANDLE, IMESSAGE_DEV_CREATEOBJECT,
							  &createInfo, OBJECT_TYPE_CONTEXT );
	if( cryptStatusError( status ) )
		return( status );

	/* Load the key into the context */
	setMessageData( &msgData, "SSH DH key", 10 );
	status = krnlSendMessage( createInfo.cryptHandle, IMESSAGE_SETATTRIBUTE_S,
							  &msgData, CRYPT_CTXINFO_LABEL );
	if( cryptStatusOK( status ) )
		{
		int keyType = CRYPT_IATTRIBUTE_KEY_SSH2;

		/* If we're being given externally-supplied DH key components, load 
		   them */
		if( keyData != NULL )
			{ setMessageData( &msgData, ( void * ) keyData, keyDataLength ); }
		else
			{
			/* Get the actual key size based on the requested key size.  The
			   spec requires that we use the smallest key size that's larger 
			   than the requested one, we allow for a small amount of slop 
			   to ensure that we don't scale up to some huge key size if the 
			   client's keysize calculation is off by a few bits */
			const int actualKeySize = \
					( requestedKeySize == CRYPT_USE_DEFAULT ) ? SSH2_DEFAULT_KEYSIZE : \
					( requestedKeySize < 128 + 8 ) ? bitsToBytes( 1024 ) : \
					( requestedKeySize < 192 + 8 ) ? bitsToBytes( 1536 ) : \
					( requestedKeySize < 256 + 8 ) ? bitsToBytes( 2048 ) : \
					( requestedKeySize < 384 + 8 ) ? bitsToBytes( 3072 ) : \
					0;

			/* If the request key size corresponds (at least approximately) 
			   to a built-in DH value, load the built-in key value, 
			   otherwise generate a new one.  In theory we should probably 
			   generate a new DH key each time:
			   

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