/* packet-ssl-utils.c * * $Id$ * * ssl manipulation functions * By Paolo Abeni * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include "packet-ssl-utils.h" void ssl_data_set(StringInfo* str, unsigned char* data, unsigned int len) { memcpy(str->data, data, len); str->data_len = len; } #ifdef HAVE_LIBGNUTLS /* hmac abstraction layer */ #define SSL_HMAC gcry_md_hd_t static inline void ssl_hmac_init(SSL_HMAC* md, const void * key, int len, int algo) { if (*(md)) gcry_md_close(*(md)); gcry_md_open(md,algo, GCRY_MD_FLAG_HMAC); gcry_md_setkey (*(md), key, len); } static inline void ssl_hmac_update(SSL_HMAC* md, const void* data, int len) { gcry_md_write(*(md), data, len); } static inline void ssl_hmac_final(SSL_HMAC* md, unsigned char* data, unsigned int* datalen) { int algo = gcry_md_get_algo (*(md)); unsigned int len = gcry_md_get_algo_dlen(algo); memcpy(data, gcry_md_read(*(md), algo), len); *datalen =len; } static inline void ssl_hmac_cleanup(SSL_HMAC* md) { gcry_md_close(*(md)); } /* memory digest abstraction layer*/ #define SSL_MD gcry_md_hd_t static inline void ssl_md_init(SSL_MD* md, int algo) { if (*(md)) gcry_md_close(*(md)); gcry_md_open(md,algo, 0); } static inline void ssl_md_update(SSL_MD* md, unsigned char* data, int len) { gcry_md_write(*(md), data, len); } static inline void ssl_md_final(SSL_MD* md, unsigned char* data, unsigned int* datalen) { int algo = gcry_md_get_algo (*(md)); int len = gcry_md_get_algo_dlen (algo); memcpy(data, gcry_md_read(*(md), algo), len); *datalen = len; } static inline void ssl_md_cleanup(SSL_MD* md) { gcry_md_close(*(md)); } /* md5 /sha abstraction layer */ #define SSL_SHA_CTX gcry_md_hd_t #define SSL_MD5_CTX gcry_md_hd_t static void ssl_sha_init(SSL_SHA_CTX* md) { if (*(md)) gcry_md_close(*(md)); gcry_md_open(md,GCRY_MD_SHA1, 0); } static inline void ssl_sha_update(SSL_SHA_CTX* md, unsigned char* data, int len) { gcry_md_write(*(md), data, len); } static inline void ssl_sha_final(unsigned char* buf, SSL_SHA_CTX* md) { memcpy(buf, gcry_md_read(*(md), GCRY_MD_SHA1), gcry_md_get_algo_dlen(GCRY_MD_SHA1)); } static inline int ssl_md5_init(SSL_MD5_CTX* md) { if (*(md)) gcry_md_close(*(md)); return gcry_md_open(md,GCRY_MD_MD5, 0); } static inline void ssl_md5_update(SSL_MD5_CTX* md, unsigned char* data, int len) { gcry_md_write(*(md), data, len); } static inline void ssl_md5_final(unsigned char* buf, SSL_MD5_CTX* md) { memcpy(buf, gcry_md_read(*(md), GCRY_MD_MD5), gcry_md_get_algo_dlen(GCRY_MD_MD5)); } /* stream cipher abstraction layer*/ static int ssl_cipher_init(gcry_cipher_hd_t *cipher, int algo, unsigned char* sk, unsigned char* iv, int mode) { int gcry_modes[]={ GCRY_CIPHER_MODE_STREAM, GCRY_CIPHER_MODE_CBC }; int err = gcry_cipher_open(cipher, algo, gcry_modes[mode], 0); if (err !=0) return -1; err = gcry_cipher_setkey(*(cipher), sk, gcry_cipher_get_algo_keylen (algo)); if (err != 0) return -1; err = gcry_cipher_setiv(*(cipher), iv, gcry_cipher_get_algo_blklen (algo)); if (err != 0) return -1; return 0; } static inline int ssl_cipher_decrypt(gcry_cipher_hd_t *cipher, unsigned char * out, int outl, const unsigned char * in,int inl) { return gcry_cipher_decrypt ( *(cipher), out, outl, in, inl); } static inline int ssl_get_digest_by_name(const char*name) { return gcry_md_map_name(name); } static inline int ssl_get_cipher_by_name(const char* name) { return gcry_cipher_map_name(name); } /* private key abstraction layer */ static inline int ssl_get_key_len(SSL_PRIVATE_KEY* pk) {return gcry_pk_get_nbits (pk); } gcry_err_code_t _gcry_rsa_decrypt (int algo, gcry_mpi_t *result, gcry_mpi_t *data, gcry_mpi_t *skey, int flags); #define PUBKEY_FLAG_NO_BLINDING (1 << 0) /* decrypt data with private key. Store decrypted data directly into input * buffer */ int ssl_private_decrypt(unsigned int len, unsigned char* encr_data, SSL_PRIVATE_KEY* pk) { int rc; size_t decr_len = 0; gcry_sexp_t s_data, s_plain; gcry_mpi_t encr_mpi; size_t i, encr_len = len; unsigned char* decr_data_ptr; gcry_mpi_t text=NULL; /* build up a mpi rappresentation for encrypted data */ rc = gcry_mpi_scan(&encr_mpi, GCRYMPI_FMT_USG,encr_data, encr_len, &encr_len); if (rc != 0 ) { ssl_debug_printf("pcry_private_decrypt: can't convert encr_data to mpi (size %d):%s\n", len, gcry_strerror(rc)); return 0; } #ifndef SSL_FAST /* put the data into a simple list */ rc = gcry_sexp_build(&s_data, NULL, "(enc-val(rsa(a%m)))", encr_mpi); if (rc != 0) { ssl_debug_printf("pcry_private_decrypt: can't build encr_sexp:%s \n", gcry_strerror(rc)); return 0; } /* pass it to libgcrypt */ rc = gcry_pk_decrypt(&s_plain, s_data, pk); gcry_sexp_release(s_data); if (rc != 0) { ssl_debug_printf("pcry_private_decrypt: can't decrypt key:%s\n", gcry_strerror(rc)); goto out; } /* convert plain text sexp to mpi format */ text = gcry_sexp_nth_mpi(s_plain, 0, 0); /* compute size requested for plaintext buffer */ decr_len = len; if (gcry_mpi_print(GCRYMPI_FMT_USG, NULL, decr_len, &decr_len, text) != 0) { ssl_debug_printf("pcry_private_decrypt: can't compute decr size:%s\n", gcry_strerror(rc)); decr_len = 0; goto out; } /* sanity check on out buffer */ if (decr_len > len) { ssl_debug_printf("pcry_private_decrypt: decrypted data is too long ?!? (%d max %d)\n", decr_len, len); return 0; } /* write plain text to encrypted data buffer */ decr_data_ptr = encr_data; if (gcry_mpi_print( GCRYMPI_FMT_USG, decr_data_ptr, decr_len, &decr_len, text) != 0) { ssl_debug_printf("pcry_private_decrypt: can't print decr data to mpi (size %d):%s\n", decr_len, gcry_strerror(rc)); g_free(decr_data_ptr); decr_len = 0; goto out; } /* strip the padding*/ rc = 0; for (i = 1; i < decr_len; i++) { if (decr_data_ptr[i] == 0) { rc = i+1; break; } } ssl_debug_printf("pcry_private_decrypt: stripping %d bytes, decr_len %d\n", rc, decr_len); ssl_print_data("decypted_unstrip_pre_master", decr_data_ptr, decr_len); g_memmove(decr_data_ptr, &decr_data_ptr[rc], decr_len - rc); decr_len -= rc; out: gcry_sexp_release(s_plain); #else /* SSL_FAST */ rc = _gcry_rsa_decrypt(0, &text, &encr_mpi, pk,0); gcry_mpi_print( GCRYMPI_FMT_USG, 0, 0, &decr_len, text); /* sanity check on out buffer */ if (decr_len > len) { ssl_debug_printf("pcry_private_decrypt: decrypted data is too long ?!? (%d max %d)\n", decr_len, len); return 0; } /* write plain text to newly allocated buffer */ decr_data_ptr = encr_data; if (gcry_mpi_print( GCRYMPI_FMT_USG, decr_data_ptr, decr_len, &decr_len, text) != 0) { ssl_debug_printf("pcry_private_decrypt: can't print decr data to mpi (size %d):%s\n", decr_len, gcry_strerror(rc)); return 0; } /* strip the padding*/ rc = 0; for (i = 1; i < decr_len; i++) { if (decr_data_ptr[i] == 0) { rc = i+1; break; } } ssl_debug_printf("pcry_private_decrypt: stripping %d bytes, decr_len %d\n", rc, decr_len); ssl_print_data("decypted_unstrip_pre_master", decr_data_ptr, decr_len); g_memmove(decr_data_ptr, &decr_data_ptr[rc], decr_len - rc); decr_len -= rc; #endif /* SSL_FAST */ gcry_mpi_release(text); return decr_len; } /* stringinfo interface */ static int ssl_data_alloc(StringInfo* str, unsigned int len) { str->data = g_malloc(len); if (!str->data) return -1; str->data_len = len; return 0; } #define PRF(ssl,secret,usage,rnd1,rnd2,out) ((ssl->version_netorder==SSLV3_VERSION)? \ ssl3_prf(secret,usage,rnd1,rnd2,out): \ tls_prf(secret,usage,rnd1,rnd2,out)) static const char *digests[]={ "MD5", "SHA1" }; static const char *ciphers[]={ "DES", "DES3", "ARCFOUR", /* gnutls does not support rc4, but this should be 100% compatible*/ "RC2", "IDEA", "AES", "AES256" }; /* look in openssl/ssl/ssl_lib.c for a complete list of available cipersuite*/ static SslCipherSuite cipher_suites[]={ {1,KEX_RSA,SIG_RSA,ENC_NULL,0,0,0,DIG_MD5,16,0, SSL_CIPHER_MODE_STREAM}, {2,KEX_RSA,SIG_RSA,ENC_NULL,0,0,0,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {3,KEX_RSA,SIG_RSA,ENC_RC4,1,128,40,DIG_MD5,16,1, SSL_CIPHER_MODE_STREAM}, {4,KEX_RSA,SIG_RSA,ENC_RC4,1,128,128,DIG_MD5,16,0, SSL_CIPHER_MODE_STREAM}, {5,KEX_RSA,SIG_RSA,ENC_RC4,1,128,128,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {6,KEX_RSA,SIG_RSA,ENC_RC2,8,128,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {7,KEX_RSA,SIG_RSA,ENC_IDEA,8,128,128,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {8,KEX_RSA,SIG_RSA,ENC_DES,8,64,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {9,KEX_RSA,SIG_RSA,ENC_DES,8,64,64,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {10,KEX_RSA,SIG_RSA,ENC_3DES,8,192,192,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {11,KEX_DH,SIG_DSS,ENC_DES,8,64,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {12,KEX_DH,SIG_DSS,ENC_DES,8,64,64,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {13,KEX_DH,SIG_DSS,ENC_3DES,8,192,192,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {14,KEX_DH,SIG_RSA,ENC_DES,8,64,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {15,KEX_DH,SIG_RSA,ENC_DES,8,64,64,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {16,KEX_DH,SIG_RSA,ENC_3DES,8,192,192,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {17,KEX_DH,SIG_DSS,ENC_DES,8,64,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {18,KEX_DH,SIG_DSS,ENC_DES,8,64,64,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {19,KEX_DH,SIG_DSS,ENC_3DES,8,192,192,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {20,KEX_DH,SIG_RSA,ENC_DES,8,64,40,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {21,KEX_DH,SIG_RSA,ENC_DES,8,64,64,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {22,KEX_DH,SIG_RSA,ENC_3DES,8,192,192,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {23,KEX_DH,SIG_NONE,ENC_RC4,1,128,40,DIG_MD5,16,1, SSL_CIPHER_MODE_STREAM}, {24,KEX_DH,SIG_NONE,ENC_RC4,1,128,128,DIG_MD5,16,0, SSL_CIPHER_MODE_STREAM}, {25,KEX_DH,SIG_NONE,ENC_DES,8,64,40,DIG_MD5,16,1, SSL_CIPHER_MODE_STREAM}, {26,KEX_DH,SIG_NONE,ENC_DES,8,64,64,DIG_MD5,16,0, SSL_CIPHER_MODE_STREAM}, {27,KEX_DH,SIG_NONE,ENC_3DES,8,192,192,DIG_MD5,16,0, SSL_CIPHER_MODE_STREAM}, {47,KEX_RSA,SIG_RSA,ENC_AES,16,128,128,DIG_SHA,20,0, SSL_CIPHER_MODE_CBC}, {53,KEX_RSA,SIG_RSA,ENC_AES256,16,256,256,DIG_SHA,20,0, SSL_CIPHER_MODE_CBC}, {96,KEX_RSA,SIG_RSA,ENC_RC4,1,128,56,DIG_MD5,16,1, SSL_CIPHER_MODE_STREAM}, {97,KEX_RSA,SIG_RSA,ENC_RC2,1,128,56,DIG_MD5,16,1, SSL_CIPHER_MODE_STREAM}, {98,KEX_RSA,SIG_RSA,ENC_DES,8,64,64,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {99,KEX_DH,SIG_DSS,ENC_DES,8,64,64,DIG_SHA,16,1, SSL_CIPHER_MODE_STREAM}, {100,KEX_RSA,SIG_RSA,ENC_RC4,1,128,56,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {101,KEX_DH,SIG_DSS,ENC_RC4,1,128,56,DIG_SHA,20,1, SSL_CIPHER_MODE_STREAM}, {102,KEX_DH,SIG_DSS,ENC_RC4,1,128,128,DIG_SHA,20,0, SSL_CIPHER_MODE_STREAM}, {-1, 0,0,0,0,0,0,0,0,0, 0} }; #define MAX_BLOCK_SIZE 16 #define MAX_KEY_SIZE 32 int ssl_find_cipher(int num,SslCipherSuite* cs) { SslCipherSuite *c; for(c=cipher_suites;c->number!=-1;c++){ if(c->number==num){ *cs=*c; return 0; } } return -1; } static int tls_hash(StringInfo* secret, StringInfo* seed, int md, StringInfo* out) { guint8 *ptr=out->data; unsigned int left=out->data_len; int tocpy; guint8 *A; guint8 _A[20],tmp[20]; unsigned int A_l,tmp_l; SSL_HMAC hm; memset(&hm, 0, sizeof(hm)); ssl_print_string("tls_hash: hash secret", secret); ssl_print_string("tls_hash: hash seed", seed); A=seed->data; A_l=seed->data_len; while(left){ ssl_hmac_init(&hm,secret->data,secret->data_len,md); ssl_hmac_update(&hm,A,A_l); ssl_hmac_final(&hm,_A,&A_l); A=_A; ssl_hmac_init(&hm,secret->data,secret->data_len,md); ssl_hmac_update(&hm,A,A_l); ssl_hmac_update(&hm,seed->data,seed->data_len); ssl_hmac_final(&hm,tmp,&tmp_l); tocpy=MIN(left,tmp_l); memcpy(ptr,tmp,tocpy); ptr+=tocpy; left-=tocpy; } ssl_hmac_cleanup(&hm); ssl_print_string("hash out", out); return (0); } static int tls_prf(StringInfo* secret, const char *usage, StringInfo* rnd1, StringInfo* rnd2, StringInfo* out) { StringInfo seed, sha_out, md5_out; guint8 *ptr; StringInfo s1, s2; unsigned int i,s_l, r=-1; int usage_len = strlen(usage); /* initalize buffer for sha, md5 random seed*/ if (ssl_data_alloc(&sha_out, MAX(out->data_len,20)) < 0) return -1; if (ssl_data_alloc(&md5_out, MAX(out->data_len,16)) < 0) goto free_sha; if (ssl_data_alloc(&seed, usage_len+rnd1->data_len+rnd2->data_len) < 0) goto free_md5; ptr=seed.data; memcpy(ptr,usage,usage_len); ptr+=usage_len; memcpy(ptr,rnd1->data,rnd1->data_len); ptr+=rnd1->data_len; memcpy(ptr,rnd2->data,rnd2->data_len); ptr+=rnd2->data_len; /* initalize buffer for client/server seeds*/ s_l=secret->data_len/2 + secret->data_len%2; if (ssl_data_alloc(&s1, s_l) < 0) goto free_seed; if (ssl_data_alloc(&s2, s_l) < 0) goto free_s1; memcpy(s1.data,secret->data,s_l); memcpy(s2.data,secret->data + (secret->data_len - s_l),s_l); ssl_debug_printf("tls_prf: tls_hash(md5 secret_len %d seed_len %d )\n", s1.data_len, seed.data_len); if(tls_hash(&s1,&seed,ssl_get_digest_by_name("MD5"),&md5_out) != 0) goto free_all; ssl_debug_printf("tls_prf: tls_hash(sha)\n"); if(tls_hash(&s2,&seed,ssl_get_digest_by_name("SHA1"),&sha_out) != 0) goto free_all; for(i=0;idata_len;i++) out->data[i]=md5_out.data[i] ^ sha_out.data[i]; r =0; ssl_print_string("PRF out",out); free_all: free(s2.data); free_s1: free(s1.data); free_seed: free(seed.data); free_md5: free(md5_out.data); free_sha: free(sha_out.data); return r; } static int ssl3_generate_export_iv(StringInfo* r1, StringInfo* r2, StringInfo* out) { SSL_MD5_CTX md5; guint8 tmp[16]; memset(&md5, 0, sizeof(md5)); ssl_md5_init(&md5); ssl_md5_update(&md5,r1->data,r1->data_len); ssl_md5_update(&md5,r2->data,r2->data_len); ssl_md5_final(tmp,&md5); memcpy(out->data,tmp,out->data_len); ssl_print_string("export iv", out); return(0); } static int ssl3_prf(StringInfo* secret, const char* usage, StringInfo* r1, StringInfo* r2,StringInfo* out) { SSL_MD5_CTX md5; SSL_SHA_CTX sha; StringInfo *rnd1,*rnd2; unsigned int off; int i=0,j; guint8 buf[20]; rnd1=r1; rnd2=r2; memset(&md5,0,sizeof(md5)); ssl_md5_init(&md5); memset(&sha,0,sizeof(sha)); ssl_sha_init(&sha); for(off=0;offdata_len;off+=16){ unsigned char outbuf[16]; int tocpy; i++; ssl_debug_printf("ssl3_prf: sha1_update(%d)\n",i); /* A, BB, CCC, ... */ for(j=0;jdata,secret->data_len); if(!strcmp(usage,"client write key") || !strcmp(usage,"server write key")){ ssl_sha_update(&sha,rnd2->data,rnd2->data_len); ssl_sha_update(&sha,rnd1->data,rnd1->data_len); } else{ ssl_sha_update(&sha,rnd1->data,rnd1->data_len); ssl_sha_update(&sha,rnd2->data,rnd2->data_len); } ssl_sha_final(buf,&sha); ssl_sha_init(&sha); ssl_debug_printf("ssl3_prf: md5_update(%d)\n",i); ssl_md5_update(&md5,secret->data,secret->data_len); ssl_md5_update(&md5,buf,20); ssl_md5_final(outbuf,&md5); tocpy=MIN(out->data_len-off,16); memcpy(out->data+off,outbuf,tocpy); ssl_md5_init(&md5); } return(0); } static int ssl_create_decoder(SslDecoder *dec, SslCipherSuite *cipher_suite, guint8 *mk, guint8 *sk, guint8 *iv) { int ciph=0; /* Find the SSLeay cipher */ if(cipher_suite->enc!=ENC_NULL) { ssl_debug_printf("ssl_create_decoder CIPHER: %s\n", ciphers[cipher_suite->enc-0x30]); ciph=ssl_get_cipher_by_name(ciphers[cipher_suite->enc-0x30]); } if (ciph == 0) { ssl_debug_printf("ssl_create_decoder can't find cipher %s\n", ciphers[cipher_suite->enc-0x30]); return -1; } /* init mac buffer: mac storage is embedded into decoder struct to save a memory allocation and waste samo more memory*/ dec->cipher_suite=cipher_suite; dec->mac_key.data = dec->_mac_key; ssl_data_set(&dec->mac_key, mk, cipher_suite->dig_len); if (ssl_cipher_init(&dec->evp,ciph,sk,iv,cipher_suite->mode) < 0) { ssl_debug_printf("ssl_create_decoder: can't create cipher id:%d mode:%d\n", ciph, cipher_suite->mode); return -1; } ssl_debug_printf("decoder initialized (digest len %d)\n", cipher_suite->dig_len); return 0; } int ssl_generate_keyring_material(SslDecryptSession*ssl_session) { StringInfo key_block; guint8 _iv_c[MAX_BLOCK_SIZE],_iv_s[MAX_BLOCK_SIZE]; guint8 _key_c[MAX_KEY_SIZE],_key_s[MAX_KEY_SIZE]; int needed; guint8 *ptr,*c_wk,*s_wk,*c_mk,*s_mk,*c_iv = _iv_c,*s_iv = _iv_s; /* if master_key is not yet generate, create it now*/ if (!(ssl_session->state & SSL_MASTER_SECRET)) { ssl_debug_printf("ssl_generate_keyring_material:PRF(pre_master_secret)\n"); if (PRF(ssl_session,&ssl_session->pre_master_secret,"master secret", &ssl_session->client_random, &ssl_session->server_random, &ssl_session->master_secret)) { ssl_debug_printf("ssl_generate_keyring_material can't generate master_secret\n"); return -1; } ssl_print_string("master secret",&ssl_session->master_secret); } /* Compute the key block. First figure out how much data we need*/ needed=ssl_session->cipher_suite.dig_len*2; needed+=ssl_session->cipher_suite.bits / 4; if(ssl_session->cipher_suite.block>1) needed+=ssl_session->cipher_suite.block*2; key_block.data_len = needed; key_block.data = g_malloc(needed); if (!key_block.data) { ssl_debug_printf("ssl_generate_keyring_material can't allacate key_block\n"); return -1; } ssl_debug_printf("ssl_generate_keyring_material sess key generation\n"); if (PRF(ssl_session,&ssl_session->master_secret,"key expansion", &ssl_session->server_random,&ssl_session->client_random, &key_block)) { ssl_debug_printf("ssl_generate_keyring_material can't generate key_block\n"); goto fail; } ssl_print_string("key expansion", &key_block); ptr=key_block.data; c_mk=ptr; ptr+=ssl_session->cipher_suite.dig_len; s_mk=ptr; ptr+=ssl_session->cipher_suite.dig_len; c_wk=ptr; ptr+=ssl_session->cipher_suite.eff_bits/8; s_wk=ptr; ptr+=ssl_session->cipher_suite.eff_bits/8; if(ssl_session->cipher_suite.block>1){ c_iv=ptr; ptr+=ssl_session->cipher_suite.block; s_iv=ptr; ptr+=ssl_session->cipher_suite.block; } if(ssl_session->cipher_suite.export){ StringInfo iv_c,iv_s; StringInfo key_c,key_s; StringInfo k; if(ssl_session->cipher_suite.block>1){ /* We only have room for MAX_BLOCK_SIZE bytes IVs, but that's all we should need. This is a sanity check */ if(ssl_session->cipher_suite.block>MAX_BLOCK_SIZE) { ssl_debug_printf("ssl_generate_keyring_material cipher suite block must be at most %d nut is %d\n", MAX_BLOCK_SIZE, ssl_session->cipher_suite.block); goto fail; } iv_c.data = _iv_c; iv_c.data_len = ssl_session->cipher_suite.block; iv_s.data = _iv_s; iv_s.data_len = ssl_session->cipher_suite.block; if(ssl_session->version_netorder==SSLV3_VERSION){ ssl_debug_printf("ssl_generate_keyring_material ssl3_generate_export_iv\n"); if (ssl3_generate_export_iv(&ssl_session->client_random, &ssl_session->server_random,&iv_c)) { ssl_debug_printf("ssl_generate_keyring_material can't generate sslv3 client iv\n"); goto fail; } ssl_debug_printf("ssl_generate_keyring_material ssl3_generate_export_iv(2)\n"); if (ssl3_generate_export_iv(&ssl_session->server_random, &ssl_session->client_random,&iv_s)) { ssl_debug_printf("ssl_generate_keyring_material can't generate sslv3 server iv\n"); goto fail; } } else{ guint8 _iv_block[MAX_BLOCK_SIZE * 2]; StringInfo iv_block; StringInfo key_null; guint8 _key_null; key_null.data = &_key_null; key_null.data_len = 0; iv_block.data = _iv_block; iv_block.data_len = ssl_session->cipher_suite.block*2; ssl_debug_printf("ssl_generate_keyring_material prf(iv_block)\n"); if(PRF(ssl_session,&key_null, "IV block", &ssl_session->client_random, &ssl_session->server_random,&iv_block)) { ssl_debug_printf("ssl_generate_keyring_material can't generate tls31 iv block\n"); goto fail; } memcpy(_iv_c,iv_block.data,ssl_session->cipher_suite.block); memcpy(_iv_s,iv_block.data+ssl_session->cipher_suite.block, ssl_session->cipher_suite.block); } c_iv=_iv_c; s_iv=_iv_s; } if (ssl_session->version_netorder==SSLV3_VERSION){ SSL_MD5_CTX md5; ssl_debug_printf("ssl_generate_keyring_material MD5(client_random)\n"); memset(&md5, 0, sizeof(md5)); ssl_md5_init(&md5); ssl_md5_update(&md5,c_wk,ssl_session->cipher_suite.eff_bits/8); ssl_md5_update(&md5,ssl_session->client_random.data, ssl_session->client_random.data_len); ssl_md5_update(&md5,ssl_session->server_random.data, ssl_session->server_random.data_len); ssl_md5_final(_key_c,&md5); c_wk=_key_c; ssl_md5_init(&md5); ssl_debug_printf("ssl_generate_keyring_material MD5(server_random)\n"); ssl_md5_update(&md5,s_wk,ssl_session->cipher_suite.eff_bits/8); ssl_md5_update(&md5,ssl_session->server_random.data, ssl_session->server_random.data_len); ssl_md5_update(&md5,ssl_session->client_random.data, ssl_session->client_random.data_len); ssl_md5_final(_key_s,&md5); s_wk=_key_s; } else{ key_c.data = _key_c; key_c.data_len = sizeof(_key_c); key_s.data = _key_s; key_s.data_len = sizeof(_key_s); k.data = c_wk; k.data_len = ssl_session->cipher_suite.eff_bits/8; ssl_debug_printf("ssl_generate_keyring_material PRF(key_c)\n"); if (PRF(ssl_session,&k,"client write key", &ssl_session->client_random, &ssl_session->server_random, &key_c)) { ssl_debug_printf("ssl_generate_keyring_material can't generate tll31 server key \n"); goto fail; } c_wk=_key_c; k.data = s_wk; k.data_len = ssl_session->cipher_suite.eff_bits/8; ssl_debug_printf("ssl_generate_keyring_material PRF(key_s)\n"); if(PRF(ssl_session,&k,"server write key", &ssl_session->client_random, &ssl_session->server_random, &key_s)) { ssl_debug_printf("ssl_generate_keyring_material can't generate tll31 client key \n"); goto fail; } s_wk=_key_s; } } /* show key material info */ ssl_print_data("Client MAC key",c_mk,ssl_session->cipher_suite.dig_len); ssl_print_data("Server MAC key",s_mk,ssl_session->cipher_suite.dig_len); ssl_print_data("Client Write key",c_wk,ssl_session->cipher_suite.bits/8); ssl_print_data("Server Write key",s_wk,ssl_session->cipher_suite.bits/8); if(ssl_session->cipher_suite.block>1) { ssl_print_data("Client Write IV",c_iv,ssl_session->cipher_suite.block); ssl_print_data("Server Write IV",s_iv,ssl_session->cipher_suite.block); } else { ssl_print_data("Client Write IV",c_iv,8); ssl_print_data("Server Write IV",s_iv,8); } /* create both client and server ciphers*/ ssl_debug_printf("ssl_generate_keyring_material ssl_create_decoder(client)\n"); if (ssl_create_decoder(&ssl_session->client, &ssl_session->cipher_suite,c_mk,c_wk,c_iv)) { ssl_debug_printf("ssl_generate_keyring_material can't init client decoder\n"); goto fail; } ssl_debug_printf("ssl_generate_keyring_material ssl_create_decoder(server)\n"); if (ssl_create_decoder(&ssl_session->server, &ssl_session->cipher_suite,s_mk,s_wk,s_iv)) { ssl_debug_printf("ssl_generate_keyring_material can't init client decoder\n"); goto fail; } g_free(key_block.data); return 0; fail: free(key_block.data); return -1; } int ssl_decrypt_pre_master_secret(SslDecryptSession*ssl_session, StringInfo* entrypted_pre_master, SSL_PRIVATE_KEY *pk) { int i; if(ssl_session->cipher_suite.kex!=KEX_RSA) { ssl_debug_printf("ssl_decrypt_pre_master_secret key %d diferent from KEX_RSA(%d)\n", ssl_session->cipher_suite.kex, KEX_RSA); return(-1); } #if 0 /* can't find any place where ephemeral_rsa is set ...*/ if(d->ephemeral_rsa) { ssl_debug_printf("ssl_decrypt_pre_master_secret ephimeral RSA\n"); return(-1); } #endif /* with tls key loading will fail if not rsa type, so no need to check*/ ssl_print_string("pre master encrypted",entrypted_pre_master); ssl_debug_printf("ssl_decrypt_pre_master_secret:RSA_private_decrypt\n"); i=ssl_private_decrypt(entrypted_pre_master->data_len, entrypted_pre_master->data, pk); if (i!=48) { ssl_debug_printf("ssl_decrypt_pre_master_secret wrong " "pre_master_secret lenght (%d, expected %d)\n", i, 48); return -1; } /* the decrypted data has been written into the pre_master key buffer */ ssl_session->pre_master_secret.data = entrypted_pre_master->data; ssl_session->pre_master_secret.data_len=48; ssl_print_string("pre master secret",&ssl_session->pre_master_secret); /* Remove the master secret if it was there. This force keying material regeneration in case we're renegotiating */ ssl_session->state &= ~SSL_MASTER_SECRET; return 0; } #define MSB(a) ((a>>8)&0xff) #define LSB(a) (a&0xff) /* convert network byte order 32 byte number to right-aligned host byte order * * 8 bytes buffer */ static int fmt_seq(guint32 num, guint8* buf) { guint32 netnum; memset(buf,0,8); netnum=g_htonl(num); memcpy(buf+4,&netnum,4); return(0); } static int tls_check_mac(SslDecoder*decoder, int ct,int ver, guint8* data, guint32 datalen, guint8* mac) { SSL_HMAC hm; int md; guint32 l; guint8 buf[20]; memset(&hm, 0, sizeof(hm)); md=ssl_get_digest_by_name(digests[decoder->cipher_suite->dig-0x40]); ssl_debug_printf("tls_check_mac mac type:%s md %d\n", digests[decoder->cipher_suite->dig-0x40], md); ssl_hmac_init(&hm,decoder->mac_key.data,decoder->mac_key.data_len,md); fmt_seq(decoder->seq,buf); decoder->seq++; ssl_hmac_update(&hm,buf,8); buf[0]=ct; ssl_hmac_update(&hm,buf,1); buf[0]=MSB(ver); buf[1]=LSB(ver); ssl_hmac_update(&hm,buf,2); buf[0]=MSB(datalen); buf[1]=LSB(datalen); ssl_hmac_update(&hm,buf,2); ssl_hmac_update(&hm,data,datalen); ssl_hmac_final(&hm,buf,&l); ssl_print_data("Mac", buf, l); if(memcmp(mac,buf,l)) return -1; ssl_hmac_cleanup(&hm); return(0); } int ssl3_check_mac(SslDecoder*decoder,int ct,guint8* data, guint32 datalen, guint8* mac) { SSL_MD mc; int md; guint32 l; guint8 buf[64],dgst[20]; int pad_ct; pad_ct=(decoder->cipher_suite->dig==DIG_SHA)?40:48; /* get cipher used for digest comptuation */ md=ssl_get_digest_by_name(digests[decoder->cipher_suite->dig-0x40]); ssl_debug_printf("ssl3_check_mac digest%s md %d\n", digests[decoder->cipher_suite->dig-0x40], md); memset(&mc, 0, sizeof(mc)); ssl_md_init(&mc,md); ssl_debug_printf("ssl3_check_mac memory digest %p\n",mc); /* do hash computation on data && padding */ ssl_md_update(&mc,decoder->mac_key.data,decoder->mac_key.data_len); memset(buf,0x36,pad_ct); ssl_md_update(&mc,buf,pad_ct); fmt_seq(decoder->seq,buf); decoder->seq++; ssl_md_update(&mc,buf,8); buf[0]=ct; ssl_md_update(&mc,buf,1); buf[0]=MSB(datalen); buf[1]=LSB(datalen); ssl_md_update(&mc,buf,2); ssl_md_update(&mc,data,datalen); ssl_md_final(&mc,dgst,&l); ssl_md_init(&mc,md); ssl_md_update(&mc,decoder->mac_key.data,decoder->mac_key.data_len); memset(buf,0x5c,pad_ct); ssl_md_update(&mc,buf,pad_ct); ssl_md_update(&mc,dgst,l); ssl_md_final(&mc,dgst,&l); if(memcmp(mac,dgst,l)) return -1; return(0); } int ssl_decrypt_record(SslDecryptSession*ssl,SslDecoder* decoder, int ct, const unsigned char* in, int inl,unsigned char*out,int* outl) { int pad, worklen; guint8 *mac; ssl_debug_printf("ssl_decrypt_record ciphertext len %d\n", inl); ssl_print_data("Ciphertext",in, inl); /* First decrypt*/ if ((pad = ssl_cipher_decrypt(&decoder->evp,out,*outl,in,inl))!= 0) ssl_debug_printf("ssl_decrypt_record: %s %s\n", gcry_strsource (pad), gcry_strerror (pad)); ssl_print_data("Plaintext",out,inl); worklen=inl; /* Now strip off the padding*/ if(decoder->cipher_suite->block!=1){ pad=out[inl-1]; worklen-=(pad+1); ssl_debug_printf("ssl_decrypt_record found padding %d final len %d\n", pad, *outl); } /* And the MAC */ worklen-=decoder->cipher_suite->dig_len; if (worklen < 0) { ssl_debug_printf("ssl_decrypt_record wrong record len/padding outlen %d\n work %d\n",*outl, worklen); return -1; } mac=out+worklen; /*ssl_print_data("Record data",out,*outl);*/ /* Now check the MAC */ ssl_debug_printf("checking mac (len %d, version %X, ct %d)\n", worklen,ssl->version_netorder, ct); if(ssl->version_netorder==0x300){ if(ssl3_check_mac(decoder,ct,out,worklen,mac) < 0) { ssl_debug_printf("ssl_decrypt_record: mac falied\n"); return -1; } } else{ if(tls_check_mac(decoder,ct,ssl->version_netorder,out,worklen,mac)< 0) { ssl_debug_printf("ssl_decrypt_record: mac falied\n"); return -1; } } ssl_debug_printf("ssl_decrypt_record: mac ok\n"); *outl = worklen; return(0); } /* old relase of gnutls does not define the appropriate macros, so get * them from the string*/ static void ssl_get_version(int* major, int* minor, int* patch) { const char* str = gnutls_check_version(NULL); ssl_debug_printf("ssl_get_version: %s\n", str); sscanf(str, "%d.%d.%d", major, minor, patch); } SSL_PRIVATE_KEY* ssl_load_key(FILE* fp) { /* gnutls make our work much harded, since we have to work internally with * s-exp formatted data, but PEM loader export only in "gnutls_datum" * format, and a datum -> s-exp convertion function does not exist. */ struct gnutls_x509_privkey_int* priv_key; gnutls_datum key; gnutls_datum m, e, d, p,q, u; int size, major, minor, patch; unsigned int bytes; unsigned int tmp_size; #ifdef SSL_FAST gcry_mpi_t* rsa_params = g_malloc(sizeof(gcry_mpi_t)*6); #else gcry_mpi_t rsa_params[6]; #endif gcry_sexp_t rsa_priv_key; /* init private key data*/ gnutls_x509_privkey_init(&priv_key); /* compute file size and load all file contents into a datum buffer*/ if (fseek(fp, 0, SEEK_END) < 0) { ssl_debug_printf("ssl_load_key: can't fseek file\n"); return NULL; } if ((size = ftell(fp)) < 0) { ssl_debug_printf("ssl_load_key: can't ftell file\n"); return NULL; } if (fseek(fp, 0, SEEK_SET) < 0) { ssl_debug_printf("ssl_load_key: can't refseek file\n"); return NULL; } key.data = g_malloc(size); key.size = size; bytes = fread(key.data, 1, key.size, fp); if (bytes < key.size) { ssl_debug_printf("ssl_load_key: can't read from file %d bytes, got %d\n", key.size, bytes); return NULL; } /* import PEM data*/ if (gnutls_x509_privkey_import(priv_key, &key, GNUTLS_X509_FMT_PEM)!=0) { ssl_debug_printf("ssl_load_key: can't import pem data\n"); return NULL; } free(key.data); /* RSA get parameter */ if (gnutls_x509_privkey_export_rsa_raw(priv_key, &m, &e, &d, &p, &q, &u) != 0) { ssl_debug_printf("ssl_load_key: can't export rsa param (is a rsa private key file ?!?)\n"); return NULL; } /* convert each rsa parameter to mpi format*/ if (gcry_mpi_scan( &rsa_params[0], GCRYMPI_FMT_USG, m.data, m.size, &tmp_size) !=0) { ssl_debug_printf("ssl_load_key: can't convert m rsa param to int (size %d)\n", m.size); return NULL; } if (gcry_mpi_scan( &rsa_params[1], GCRYMPI_FMT_USG, e.data, e.size, &tmp_size) != 0) { ssl_debug_printf("ssl_load_key: can't convert e rsa param to int (size %d)\n", e.size); return NULL; } /* * note: openssl and gnutls use 'p' and 'q' with opposite meaning: * our 'p' must be equal to 'q' as provided from openssl and viceversa */ if (gcry_mpi_scan( &rsa_params[2], GCRYMPI_FMT_USG, d.data, d.size, &tmp_size) !=0) { ssl_debug_printf("ssl_load_key: can't convert d rsa param to int (size %d)\n", d.size); return NULL; } if (gcry_mpi_scan( &rsa_params[3], GCRYMPI_FMT_USG, q.data, q.size, &tmp_size) !=0) { ssl_debug_printf("ssl_load_key: can't convert q rsa param to int (size %d)\n", q.size); return NULL; } if (gcry_mpi_scan( &rsa_params[4], GCRYMPI_FMT_USG, p.data, p.size, &tmp_size) !=0) { ssl_debug_printf("ssl_load_key: can't convert p rsa param to int (size %d)\n", p.size); return NULL; } if (gcry_mpi_scan( &rsa_params[5], GCRYMPI_FMT_USG, u.data, u.size, &tmp_size) !=0) { ssl_debug_printf("ssl_load_key: can't convert u rsa param to int (size %d)\n", m.size); return NULL; } ssl_get_version(&major, &minor, &patch); /* certain versions of gnutls require swap of rsa params 'p' and 'q' */ if ((major <= 1) && (minor <= 0) && (patch <=13)) { gcry_mpi_t tmp; ssl_debug_printf("ssl_load_key: swapping p and q parametes\n"); tmp = rsa_params[4]; rsa_params[4] = rsa_params[3]; rsa_params[3] = tmp; } if (gcry_sexp_build( &rsa_priv_key, NULL, "(private-key(rsa((n%m)(e%m)(d%m)(p%m)(q%m)(u%m))))", rsa_params[0], rsa_params[1], rsa_params[2], rsa_params[3], rsa_params[4], rsa_params[5]) != 0) { ssl_debug_printf("ssl_load_key: can't built rsa private key s-exp\n"); return NULL; } #if SSL_FAST return rsa_params; #else { int i; for (i=0; i< 6; i++) gcry_mpi_release(rsa_params[i]); } return rsa_priv_key; #endif } void ssl_free_key(SSL_PRIVATE_KEY* key) { #if SSL_FAST int i; for (i=0; i< 6; i++) gcry_mpi_release(key[i]); #else gcry_sexp_release(key); #endif } #ifdef SSL_DECRYPT_DEBUG static FILE* myout=NULL; #endif void ssl_lib_init(void) { gnutls_global_init(); #ifdef SSL_DECRYPT_DEBUG #ifdef _WIN32 /* we don't have standard I/O file available, open a log */ myout = fopen("ssl-decrypt.txt","w"); if (!myout) #endif /* _WIN32 */ myout = stderr; #endif /* SSL_DECRYPT_DEBUG */ } #else /* HAVE_LIBGNUTLS */ /* no libgnutl: dummy operation to keep interface consistent*/ void ssl_lib_init(void) { } SSL_PRIVATE_KEY* ssl_load_key(FILE* fp) { ssl_debug_printf("ssl_load_key: impossible without glutls. fp %p\n",fp); return NULL; } void ssl_free_key(SSL_PRIVATE_KEY* key _U_) { } int ssl_find_cipher(int num,SslCipherSuite* cs) { ssl_debug_printf("ssl_find_cipher: dummy without glutls. num %d cs %p\n", num,cs); return 0; } int ssl_generate_keyring_material(SslDecryptSession*ssl) { ssl_debug_printf("ssl_generate_keyring_material: impossible without glutls. ssl %p\n", ssl); return 0; } int ssl_decrypt_pre_master_secret(SslDecryptSession* ssl_session, StringInfo* entrypted_pre_master, SSL_PRIVATE_KEY *pk) { ssl_debug_printf("ssl_decrypt_pre_master_secret: impossible without glutls." " ssl %p entrypted_pre_master %p pk %p\n", ssl_session, entrypted_pre_master, pk); return 0; } int ssl_decrypt_record(SslDecryptSession*ssl,SslDecoder* decoder, int ct, const unsigned char* in, int inl,unsigned char*out,int* outl) { ssl_debug_printf("ssl_decrypt_record: impossible without gnutls. ssl %p" "decoder %p ct %d, in %p inl %d out %p outl %p\n", ssl, decoder, ct, in, inl, out, outl); return 0; } #endif /* HAVE_LIBGNUTLS */ /* get ssl data for this session. if no ssl data is found allocate a new one*/ void ssl_session_init(SslDecryptSession* ssl_session) { ssl_debug_printf("ssl_session_init: initializing ptr %p size %lu\n", ssl_session, (unsigned long)sizeof(SslDecryptSession)); ssl_session->master_secret.data = ssl_session->_master_secret; ssl_session->session_id.data = ssl_session->_session_id; ssl_session->client_random.data = ssl_session->_client_random; ssl_session->server_random.data = ssl_session->_server_random; ssl_session->master_secret.data_len = 48; } #ifdef SSL_DECRYPT_DEBUG void ssl_debug_printf(const char* fmt, ...) { va_list ap; int ret=0; va_start(ap, fmt); ret += vfprintf(myout, fmt, ap); va_end(ap); fflush(myout); } void ssl_print_text_data(const char* name, const unsigned char* data, int len) { int i; fprintf(myout,"%s: ",name); for (i=0; i< len; i++) { fprintf(myout,"%c",data[i]); } fprintf(myout,"\n"); fflush(myout); } void ssl_print_data(const char* name, const unsigned char* data, int len) { int i; fprintf(myout,"%s[%d]:\n",name, len); for (i=0; i< len; i++) { if ((i>0) && (i%16 == 0)) fprintf(myout,"\n"); fprintf(myout,"%.2x ",data[i]&255); } fprintf(myout,"\n"); fflush(myout); } void ssl_print_string(const char* name, const StringInfo* data) { ssl_print_data(name, data->data, data->data_len); } #endif /* SSL_DECRYPT_DEBUG */