diff options
Diffstat (limited to 'common-algo.c')
| -rw-r--r-- | common-algo.c | 234 |
1 files changed, 147 insertions, 87 deletions
diff --git a/common-algo.c b/common-algo.c index 2f896ab..8b39892 100644 --- a/common-algo.c +++ b/common-algo.c @@ -30,6 +30,9 @@ #include "dh_groups.h" #include "ltc_prng.h" #include "ecc.h" +#include "gcm.h" +#include "chachapoly.h" +#include "ssh.h" /* This file (algo.c) organises the ciphers which can be used, and is used to * decide which ciphers/hashes/compression/signing to use during key exchange*/ @@ -61,10 +64,6 @@ static const struct dropbear_cipher dropbear_aes256 = static const struct dropbear_cipher dropbear_aes128 = {&aes_desc, 16, 16}; #endif -#if DROPBEAR_BLOWFISH -static const struct dropbear_cipher dropbear_blowfish = - {&blowfish_desc, 16, 8}; -#endif #if DROPBEAR_TWOFISH256 static const struct dropbear_cipher dropbear_twofish256 = {&twofish_desc, 32, 16}; @@ -86,11 +85,11 @@ const struct dropbear_cipher dropbear_nocipher = * about the symmetric_CBC vs symmetric_CTR cipher_state pointer */ #if DROPBEAR_ENABLE_CBC_MODE const struct dropbear_cipher_mode dropbear_mode_cbc = - {(void*)cbc_start, (void*)cbc_encrypt, (void*)cbc_decrypt}; + {(void*)cbc_start, (void*)cbc_encrypt, (void*)cbc_decrypt, NULL, NULL, NULL}; #endif /* DROPBEAR_ENABLE_CBC_MODE */ const struct dropbear_cipher_mode dropbear_mode_none = - {void_start, void_cipher, void_cipher}; + {void_start, void_cipher, void_cipher, NULL, NULL, NULL}; #if DROPBEAR_ENABLE_CTR_MODE /* a wrapper to make ctr_start and cbc_start look the same */ @@ -101,7 +100,7 @@ static int dropbear_big_endian_ctr_start(int cipher, return ctr_start(cipher, IV, key, keylen, num_rounds, CTR_COUNTER_BIG_ENDIAN, ctr); } const struct dropbear_cipher_mode dropbear_mode_ctr = - {(void*)dropbear_big_endian_ctr_start, (void*)ctr_encrypt, (void*)ctr_decrypt}; + {(void*)dropbear_big_endian_ctr_start, (void*)ctr_encrypt, (void*)ctr_decrypt, NULL, NULL, NULL}; #endif /* DROPBEAR_ENABLE_CTR_MODE */ /* Mapping of ssh hashes to libtomcrypt hashes, including keysize etc. @@ -137,6 +136,19 @@ const struct dropbear_hash dropbear_nohash = * that is also supported by the server will get used. */ algo_type sshciphers[] = { +#if DROPBEAR_CHACHA20POLY1305 + {"chacha20-poly1305@openssh.com", 0, &dropbear_chachapoly, 1, &dropbear_mode_chachapoly}, +#endif + +#if DROPBEAR_ENABLE_GCM_MODE +#if DROPBEAR_AES128 + {"aes128-gcm@openssh.com", 0, &dropbear_aes128, 1, &dropbear_mode_gcm}, +#endif +#if DROPBEAR_AES256 + {"aes256-gcm@openssh.com", 0, &dropbear_aes256, 1, &dropbear_mode_gcm}, +#endif +#endif /* DROPBEAR_ENABLE_GCM_MODE */ + #if DROPBEAR_ENABLE_CTR_MODE #if DROPBEAR_AES128 {"aes128-ctr", 0, &dropbear_aes128, 1, &dropbear_mode_ctr}, @@ -169,15 +181,18 @@ algo_type sshciphers[] = { #if DROPBEAR_TWOFISH128 {"twofish128-cbc", 0, &dropbear_twofish128, 1, &dropbear_mode_cbc}, #endif +#endif /* DROPBEAR_ENABLE_CBC_MODE */ + #if DROPBEAR_3DES +#if DROPBEAR_ENABLE_CTR_MODE {"3des-ctr", 0, &dropbear_3des, 1, &dropbear_mode_ctr}, #endif -#if DROPBEAR_3DES +#if DROPBEAR_ENABLE_CBC_MODE {"3des-cbc", 0, &dropbear_3des, 1, &dropbear_mode_cbc}, #endif -#if DROPBEAR_BLOWFISH - {"blowfish-cbc", 0, &dropbear_blowfish, 1, &dropbear_mode_cbc}, -#endif +#endif /* DROPBEAR_3DES */ + +#if DROPBEAR_ENABLE_CBC_MODE #endif /* DROPBEAR_ENABLE_CBC_MODE */ {NULL, 0, NULL, 0, NULL} }; @@ -221,23 +236,31 @@ algo_type ssh_nocompress[] = { {NULL, 0, NULL, 0, NULL} }; -algo_type sshhostkey[] = { +algo_type sigalgs[] = { +#if DROPBEAR_ED25519 + {"ssh-ed25519", DROPBEAR_SIGNATURE_ED25519, NULL, 1, NULL}, +#endif #if DROPBEAR_ECDSA #if DROPBEAR_ECC_256 - {"ecdsa-sha2-nistp256", DROPBEAR_SIGNKEY_ECDSA_NISTP256, NULL, 1, NULL}, + {"ecdsa-sha2-nistp256", DROPBEAR_SIGNATURE_ECDSA_NISTP256, NULL, 1, NULL}, #endif #if DROPBEAR_ECC_384 - {"ecdsa-sha2-nistp384", DROPBEAR_SIGNKEY_ECDSA_NISTP384, NULL, 1, NULL}, + {"ecdsa-sha2-nistp384", DROPBEAR_SIGNATURE_ECDSA_NISTP384, NULL, 1, NULL}, #endif #if DROPBEAR_ECC_521 - {"ecdsa-sha2-nistp521", DROPBEAR_SIGNKEY_ECDSA_NISTP521, NULL, 1, NULL}, + {"ecdsa-sha2-nistp521", DROPBEAR_SIGNATURE_ECDSA_NISTP521, NULL, 1, NULL}, #endif #endif #if DROPBEAR_RSA - {"ssh-rsa", DROPBEAR_SIGNKEY_RSA, NULL, 1, NULL}, +#if DROPBEAR_RSA_SHA256 + {"rsa-sha2-256", DROPBEAR_SIGNATURE_RSA_SHA256, NULL, 1, NULL}, +#endif +#if DROPBEAR_RSA_SHA1 + {"ssh-rsa", DROPBEAR_SIGNATURE_RSA_SHA1, NULL, 1, NULL}, +#endif #endif #if DROPBEAR_DSS - {"ssh-dss", DROPBEAR_SIGNKEY_DSS, NULL, 1, NULL}, + {"ssh-dss", DROPBEAR_SIGNATURE_DSS, NULL, 1, NULL}, #endif {NULL, 0, NULL, 0, NULL} }; @@ -255,8 +278,6 @@ static const struct dropbear_kex kex_dh_group14_sha256 = {DROPBEAR_KEX_NORMAL_DH static const struct dropbear_kex kex_dh_group16_sha512 = {DROPBEAR_KEX_NORMAL_DH, dh_p_16, DH_P_16_LEN, NULL, &sha512_desc }; #endif -/* These can't be const since dropbear_ecc_fill_dp() fills out - ecc_curve at runtime */ #if DROPBEAR_ECDH #if DROPBEAR_ECC_256 static const struct dropbear_kex kex_ecdh_nistp256 = {DROPBEAR_KEX_ECDH, NULL, 0, &ecc_curve_nistp256, &sha256_desc }; @@ -274,6 +295,7 @@ static const struct dropbear_kex kex_ecdh_nistp521 = {DROPBEAR_KEX_ECDH, NULL, 0 static const struct dropbear_kex kex_curve25519 = {DROPBEAR_KEX_CURVE25519, NULL, 0, NULL, &sha256_desc }; #endif +/* data == NULL for non-kex algorithm identifiers */ algo_type sshkex[] = { #if DROPBEAR_CURVE25519 {"curve25519-sha256", 0, &kex_curve25519, 1, NULL}, @@ -303,49 +325,122 @@ algo_type sshkex[] = { {"diffie-hellman-group16-sha512", 0, &kex_dh_group16_sha512, 1, NULL}, #endif #if DROPBEAR_KEXGUESS2 - {KEXGUESS2_ALGO_NAME, KEXGUESS2_ALGO_ID, NULL, 1, NULL}, + {KEXGUESS2_ALGO_NAME, 0, NULL, 1, NULL}, +#endif +#if DROPBEAR_EXT_INFO +#if DROPBEAR_CLIENT + /* Set unusable by svr_algos_initialise() */ + {SSH_EXT_INFO_C, 0, NULL, 1, NULL}, +#endif #endif {NULL, 0, NULL, 0, NULL} }; -/* algolen specifies the length of algo, algos is our local list to match - * against. - * Returns DROPBEAR_SUCCESS if we have a match for algo, DROPBEAR_FAILURE - * otherwise */ -int have_algo(const char* algo, size_t algolen, const algo_type algos[]) { +/* Output a comma separated list of algorithms to a buffer */ +void buf_put_algolist_all(buffer * buf, const algo_type localalgos[], int useall) { + unsigned int i, len; + unsigned int donefirst = 0; + unsigned int startpos; - int i; + startpos = buf->pos; + /* Placeholder for length */ + buf_putint(buf, 0); + for (i = 0; localalgos[i].name != NULL; i++) { + if (localalgos[i].usable || useall) { + if (donefirst) { + buf_putbyte(buf, ','); + } + donefirst = 1; + len = strlen(localalgos[i].name); + buf_putbytes(buf, (const unsigned char *) localalgos[i].name, len); + } + } + /* Fill out the length */ + len = buf->pos - startpos - 4; + buf_setpos(buf, startpos); + buf_putint(buf, len); + TRACE(("algolist add %d '%*s'", len, len, buf_getptr(buf, len))) + buf_incrwritepos(buf, len); +} - for (i = 0; algos[i].name != NULL; i++) { - if (strlen(algos[i].name) == algolen - && (strncmp(algos[i].name, algo, algolen) == 0)) { - return DROPBEAR_SUCCESS; +void buf_put_algolist(buffer * buf, const algo_type localalgos[]) { + buf_put_algolist_all(buf, localalgos, 0); +} + +/* returns a list of pointers into algolist, of null-terminated names. + ret_list should be passed in with space for *ret_count elements, + on return *ret_count has the number of names filled. + algolist is modified. */ +static void get_algolist(char* algolist, unsigned int algolist_len, + const char* *ret_list, unsigned int *ret_count) { + unsigned int max_count = *ret_count; + unsigned int i; + + if (*ret_count == 0) { + return; + } + if (algolist_len > MAX_PROPOSED_ALGO*(MAX_NAME_LEN+1)) { + *ret_count = 0; } + + /* ret_list will contain a list of the strings parsed out. + We will have at least one string (even if it's just "") */ + ret_list[0] = algolist; + *ret_count = 1; + for (i = 0; i < algolist_len; i++) { + if (algolist[i] == '\0') { + /* someone is trying something strange */ + *ret_count = 0; + return; } - return DROPBEAR_FAILURE; + if (algolist[i] == ',') { + if (*ret_count >= max_count) { + /* Too many */ + *ret_count = 0; + return; + } + algolist[i] = '\0'; + ret_list[*ret_count] = &algolist[i+1]; + (*ret_count)++; + } + } } -/* Output a comma separated list of algorithms to a buffer */ -void buf_put_algolist(buffer * buf, const algo_type localalgos[]) { +/* Return DROPBEAR_SUCCESS if the namelist contains algo, +DROPBEAR_FAILURE otherwise. buf position is not incremented. */ +int buf_has_algo(buffer *buf, const char *algo) { + unsigned char* algolist = NULL; + unsigned int orig_pos = buf->pos; + unsigned int len, remotecount, i; + const char *remotenames[MAX_PROPOSED_ALGO]; + int ret = DROPBEAR_FAILURE; - unsigned int i, len; - unsigned int donefirst = 0; - buffer *algolist = NULL; + algolist = buf_getstring(buf, &len); + remotecount = MAX_PROPOSED_ALGO; + get_algolist(algolist, len, remotenames, &remotecount); + for (i = 0; i < remotecount; i++) + { + if (strcmp(remotenames[i], algo) == 0) { + ret = DROPBEAR_SUCCESS; + break; + } + } + if (algolist) { + m_free(algolist); + } + buf_setpos(buf, orig_pos); + return ret; +} - algolist = buf_new(300); - for (i = 0; localalgos[i].name != NULL; i++) { - if (localalgos[i].usable) { - if (donefirst) - buf_putbyte(algolist, ','); - donefirst = 1; - len = strlen(localalgos[i].name); - buf_putbytes(algolist, (const unsigned char *) localalgos[i].name, len); +algo_type * first_usable_algo(algo_type algos[]) { + int i; + for (i = 0; algos[i].name != NULL; i++) { + if (algos[i].usable) { + return &algos[i]; } } - buf_putstring(buf, (const char*)algolist->data, algolist->len); - TRACE(("algolist add '%*s'", algolist->len, algolist->data)) - buf_free(algolist); + return NULL; } /* match the first algorithm in the comma-separated list in buf which is @@ -354,9 +449,7 @@ void buf_put_algolist(buffer * buf, const algo_type localalgos[]) { * 0 otherwise. This is used for checking if the kexalgo/hostkeyalgos are * guessed correctly */ algo_type * buf_match_algo(buffer* buf, algo_type localalgos[], - enum kexguess2_used *kexguess2, int *goodguess) -{ - + int kexguess2, int *goodguess) { char * algolist = NULL; const char *remotenames[MAX_PROPOSED_ALGO], *localnames[MAX_PROPOSED_ALGO]; unsigned int len; @@ -371,40 +464,8 @@ algo_type * buf_match_algo(buffer* buf, algo_type localalgos[], /* get the comma-separated list from the buffer ie "algo1,algo2,algo3" */ algolist = buf_getstring(buf, &len); TRACE(("buf_match_algo: %s", algolist)) - if (len > MAX_PROPOSED_ALGO*(MAX_NAME_LEN+1)) { - goto out; - } - - /* remotenames will contain a list of the strings parsed out */ - /* We will have at least one string (even if it's just "") */ - remotenames[0] = algolist; - remotecount = 1; - for (i = 0; i < len; i++) { - if (algolist[i] == '\0') { - /* someone is trying something strange */ - goto out; - } - if (algolist[i] == ',') { - algolist[i] = '\0'; - remotenames[remotecount] = &algolist[i+1]; - remotecount++; - } - if (remotecount >= MAX_PROPOSED_ALGO) { - break; - } - } - if (kexguess2 && *kexguess2 == KEXGUESS2_LOOK) { - for (i = 0; i < remotecount; i++) - { - if (strcmp(remotenames[i], KEXGUESS2_ALGO_NAME) == 0) { - *kexguess2 = KEXGUESS2_YES; - break; - } - } - if (*kexguess2 == KEXGUESS2_LOOK) { - *kexguess2 = KEXGUESS2_NO; - } - } + remotecount = MAX_PROPOSED_ALGO; + get_algolist(algolist, len, remotenames, &remotecount); for (i = 0; localalgos[i].name != NULL; i++) { if (localalgos[i].usable) { @@ -436,12 +497,11 @@ algo_type * buf_match_algo(buffer* buf, algo_type localalgos[], } if (strcmp(servnames[j], clinames[i]) == 0) { /* set if it was a good guess */ - if (goodguess && kexguess2) { - if (*kexguess2 == KEXGUESS2_YES) { + if (goodguess != NULL) { + if (kexguess2) { if (i == 0) { *goodguess = 1; } - } else { if (i == 0 && j == 0) { *goodguess = 1; |