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author | Kozlov Dmitry <dima@server> | 2010-10-06 16:55:05 +0400 |
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committer | Kozlov Dmitry <dima@server> | 2010-10-06 16:55:05 +0400 |
commit | 45b3c9c5bdd896f51f47e29069e3c030ddb17d51 (patch) | |
tree | cbec5824ffb2eee20b98ad9892a357304384ff01 /accel-pptpd/auth/auth_mschap_v1.c | |
parent | ba3db9f17477ea4b49c266c5cb50f63f3b074db2 (diff) | |
parent | 01ccd98495c9da1e79f7867bf52416b23f20200d (diff) | |
download | accel-ppp-45b3c9c5bdd896f51f47e29069e3c030ddb17d51.tar.gz accel-ppp-45b3c9c5bdd896f51f47e29069e3c030ddb17d51.zip |
merged branch accel-pptpd
Diffstat (limited to 'accel-pptpd/auth/auth_mschap_v1.c')
-rw-r--r-- | accel-pptpd/auth/auth_mschap_v1.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/accel-pptpd/auth/auth_mschap_v1.c b/accel-pptpd/auth/auth_mschap_v1.c new file mode 100644 index 00000000..5b4935ea --- /dev/null +++ b/accel-pptpd/auth/auth_mschap_v1.c @@ -0,0 +1,453 @@ +#include <stdint.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <fcntl.h> +#include <errno.h> +#include <stdio.h> +#include <byteswap.h> +#include <arpa/inet.h> + +#include <openssl/md4.h> +#include <openssl/des.h> + +#include "log.h" +#include "ppp.h" +#include "ppp_auth.h" +#include "ppp_lcp.h" +#include "pwdb.h" + +#include "memdebug.h" + +#define MSCHAP_V1 0x80 + +#define CHAP_CHALLENGE 1 +#define CHAP_RESPONSE 2 +#define CHAP_SUCCESS 3 +#define CHAP_FAILURE 4 + +#define VALUE_SIZE 8 +#define RESPONSE_VALUE_SIZE (24+24+1) + +#define MSG_FAILURE "E=691 R=0" +#define MSG_SUCCESS "Authentication successed" + +#define HDR_LEN (sizeof(struct chap_hdr_t)-2) + +static int conf_timeout = 5; +static int conf_interval = 0; +static int conf_max_failure = 3; + +static int urandom_fd; + +struct chap_hdr_t +{ + uint16_t proto; + uint8_t code; + uint8_t id; + uint16_t len; +} __attribute__((packed)); + +struct chap_challenge_t +{ + struct chap_hdr_t hdr; + uint8_t val_size; + uint8_t val[VALUE_SIZE]; + char name[0]; +} __attribute__((packed)); + +struct chap_response_t +{ + struct chap_hdr_t hdr; + uint8_t val_size; + uint8_t lm_hash[24]; + uint8_t nt_hash[24]; + uint8_t flags; + char name[0]; +} __attribute__((packed)); + +struct chap_failure_t +{ + struct chap_hdr_t hdr; + char message[sizeof(MSG_FAILURE)]; +} __attribute__((packed)); + +struct chap_success_t +{ + struct chap_hdr_t hdr; + char message[sizeof(MSG_SUCCESS)]; +} __attribute__((packed)); + + +struct chap_auth_data_t +{ + struct auth_data_t auth; + struct ppp_handler_t h; + struct ppp_t *ppp; + int id; + uint8_t val[VALUE_SIZE]; + struct triton_timer_t timeout; + struct triton_timer_t interval; + int failure; + int started:1; +}; + +static void chap_send_challenge(struct chap_auth_data_t *ad); +static void chap_recv(struct ppp_handler_t *h); +static int chap_check_response(struct chap_auth_data_t *ad, struct chap_response_t *res, const char *name); +static void chap_timeout(struct triton_timer_t *t); +static void chap_restart(struct triton_timer_t *t); + +static void print_buf(const uint8_t *buf,int size) +{ + int i; + for (i = 0; i < size; i++) + log_ppp_info("%x", buf[i]); +} +static void print_str(const char *buf, int size) +{ + int i; + for(i = 0; i < size; i++) + log_ppp_info("%c", buf[i]); +} + +static struct auth_data_t* auth_data_init(struct ppp_t *ppp) +{ + struct chap_auth_data_t *d = _malloc(sizeof(*d)); + + memset(d, 0, sizeof(*d)); + d->auth.proto = PPP_CHAP; + d->ppp = ppp; + + return &d->auth; +} + +static void auth_data_free(struct ppp_t *ppp, struct auth_data_t *auth) +{ + struct chap_auth_data_t *d = container_of(auth, typeof(*d), auth); + + _free(d); +} + +static int chap_start(struct ppp_t *ppp, struct auth_data_t *auth) +{ + struct chap_auth_data_t *d = container_of(auth, typeof(*d), auth); + + d->h.proto = PPP_CHAP; + d->h.recv = chap_recv; + d->timeout.expire = chap_timeout; + d->timeout.period = conf_timeout * 1000; + d->interval.expire = chap_restart; + d->interval.period = conf_interval * 1000; + + ppp_register_chan_handler(ppp, &d->h); + + chap_send_challenge(d); + + return 0; +} + +static int chap_finish(struct ppp_t *ppp, struct auth_data_t *auth) +{ + struct chap_auth_data_t *d = container_of(auth, typeof(*d), auth); + + if (d->timeout.tpd) + triton_timer_del(&d->timeout); + + if (d->interval.tpd) + triton_timer_del(&d->interval); + + ppp_unregister_handler(ppp, &d->h); + + return 0; +} + +static void chap_timeout(struct triton_timer_t *t) +{ + struct chap_auth_data_t *d = container_of(t, typeof(*d), timeout); + + if (conf_ppp_verbose) + log_ppp_warn("mschap-v1: timeout\n"); + + if (++d->failure == conf_max_failure) { + if (d->started) + ppp_terminate(d->ppp, 0); + else + auth_failed(d->ppp); + } else { + --d->id; + chap_send_challenge(d); + } +} + +static void chap_restart(struct triton_timer_t *t) +{ + struct chap_auth_data_t *d = container_of(t, typeof(*d), interval); + + chap_send_challenge(d); +} + +static int lcp_send_conf_req(struct ppp_t *ppp, struct auth_data_t *d, uint8_t *ptr) +{ + *ptr = MSCHAP_V1; + return 1; +} + +static int lcp_recv_conf_req(struct ppp_t *ppp, struct auth_data_t *d, uint8_t *ptr) +{ + if (*ptr == MSCHAP_V1) + return LCP_OPT_ACK; + return LCP_OPT_NAK; +} + +static void chap_send_failure(struct chap_auth_data_t *ad) +{ + struct chap_failure_t msg = { + .hdr.proto = htons(PPP_CHAP), + .hdr.code = CHAP_FAILURE, + .hdr.id = ad->id, + .hdr.len = htons(sizeof(msg)-1-2), + .message = MSG_FAILURE, + }; + + if (conf_ppp_verbose) + log_ppp_info("send [MSCHAP-v1 Failure id=%x \"%s\"]\n", msg.hdr.id, MSG_FAILURE); + + ppp_chan_send(ad->ppp,&msg,ntohs(msg.hdr.len)+2); +} + +static void chap_send_success(struct chap_auth_data_t *ad) +{ + struct chap_success_t msg = { + .hdr.proto = htons(PPP_CHAP), + .hdr.code = CHAP_SUCCESS, + .hdr.id = ad->id, + .hdr.len = htons(sizeof(msg)-1-2), + .message = MSG_SUCCESS, + }; + + if (conf_ppp_verbose) + log_ppp_info("send [MSCHAP-v1 Success id=%x \"%s\"]\n", msg.hdr.id, MSG_SUCCESS); + + ppp_chan_send(ad->ppp, &msg, ntohs(msg.hdr.len) + 2); +} + +static void chap_send_challenge(struct chap_auth_data_t *ad) +{ + struct chap_challenge_t msg = { + .hdr.proto = htons(PPP_CHAP), + .hdr.code = CHAP_CHALLENGE, + .hdr.id = ++ad->id, + .hdr.len = htons(sizeof(msg) - 2), + .val_size = VALUE_SIZE, + }; + + read(urandom_fd, ad->val, VALUE_SIZE); + memcpy(msg.val, ad->val, VALUE_SIZE); + + if (conf_ppp_verbose) { + log_ppp_info("send [MSCHAP-v1 Challenge id=%x <", msg.hdr.id); + print_buf(msg.val, VALUE_SIZE); + log_ppp_info(">]\n"); + } + + ppp_chan_send(ad->ppp, &msg, ntohs(msg.hdr.len) + 2); + + if (conf_timeout && !ad->timeout.tpd) + triton_timer_add(ad->ppp->ctrl->ctx, &ad->timeout, 0); +} + +static void chap_recv_response(struct chap_auth_data_t *ad, struct chap_hdr_t *hdr) +{ + struct chap_response_t *msg = (struct chap_response_t*)hdr; + char *name; + int r; + + if (ad->timeout.tpd) + triton_timer_del(&ad->timeout); + + if (conf_ppp_verbose) { + log_ppp_info("recv [MSCHAP-v1 Response id=%x <", msg->hdr.id); + print_buf(msg->lm_hash, 24); + log_ppp_info(">, <"); + print_buf(msg->nt_hash, 24); + log_ppp_info(">, F=%i, name=\"", msg->flags); + print_str(msg->name, ntohs(msg->hdr.len) - sizeof(*msg) + 2); + log_ppp_info("\"]\n"); + } + + if (msg->hdr.id != ad->id) { + if (conf_ppp_verbose) + log_ppp_error("mschap-v1: id mismatch\n"); + chap_send_failure(ad); + if (ad->started) + ppp_terminate(ad->ppp, 0); + else + auth_failed(ad->ppp); + } + + if (msg->val_size != RESPONSE_VALUE_SIZE) { + log_ppp_error("mschap-v1: incorrect value-size (%i)\n", msg->val_size); + chap_send_failure(ad); + if (ad->started) + ppp_terminate(ad->ppp, 0); + else + auth_failed(ad->ppp); + } + + name = _strndup(msg->name, ntohs(msg->hdr.len) - sizeof(*msg) + 2); + if (!name) { + log_emerg("mschap-v1: out of memory\n"); + if (ad->started) + ppp_terminate(ad->ppp, 0); + else + auth_failed(ad->ppp); + return; + } + + r = pwdb_check(ad->ppp, name, PPP_CHAP, MSCHAP_V1, ad->id, ad->val, VALUE_SIZE, msg->lm_hash, msg->nt_hash, msg->flags); + if (r == PWDB_NO_IMPL) + r = chap_check_response(ad, msg, name); + + if (r == PWDB_DENIED) { + chap_send_failure(ad); + if (ad->started) + ppp_terminate(ad->ppp, 0); + else + auth_failed(ad->ppp); + _free(name); + } else { + chap_send_success(ad); + if (!ad->started) { + ad->started = 1; + if (conf_interval) + triton_timer_add(ad->ppp->ctrl->ctx, &ad->interval, 0); + auth_successed(ad->ppp, name); + } + } +} + +static void des_encrypt(const uint8_t *input, const uint8_t *key, uint8_t *output) +{ + int i, j, parity; + union + { + uint64_t u64; + uint8_t buf[8]; + } p_key; + DES_cblock cb; + DES_cblock res; + DES_key_schedule ks; + + memcpy(p_key.buf, key, 7); + p_key.u64 = bswap_64(p_key.u64); + + for (i = 0; i < 8; i++) { + cb[i] = (((p_key.u64 << (7 * i)) >> 56) & 0xfe); + for( j = 0, parity = 0; j < 7; j++) + if ((cb[i] >> (j + 1)) & 1) + parity++; + cb[i] |= (~parity) & 1; + } + + DES_set_key_checked(&cb, &ks); + memcpy(cb, input, 8); + DES_ecb_encrypt(&cb, &res, &ks, DES_ENCRYPT); + memcpy(output, res, 8); +} + +static int chap_check_response(struct chap_auth_data_t *ad, struct chap_response_t *msg, const char *name) +{ + MD4_CTX md4_ctx; + uint8_t z_hash[21]; + uint8_t nt_hash[24]; + char *passwd; + char *u_passwd; + int i; + + passwd = pwdb_get_passwd(ad->ppp,name); + if (!passwd) { + if (conf_ppp_verbose) + log_ppp_warn("mschap-v1: user not found\n"); + chap_send_failure(ad); + return PWDB_DENIED; + } + + u_passwd = _malloc(strlen(passwd) * 2); + for (i = 0; i< strlen(passwd); i++) { + u_passwd[i * 2] = passwd[i]; + u_passwd[i * 2 + 1] = 0; + } + + memset(z_hash, 0, sizeof(z_hash)); + MD4_Init(&md4_ctx); + MD4_Update(&md4_ctx, u_passwd, strlen(passwd) * 2); + MD4_Final(z_hash, &md4_ctx); + + des_encrypt(ad->val, z_hash, nt_hash); + des_encrypt(ad->val, z_hash + 7, nt_hash + 8); + des_encrypt(ad->val, z_hash + 14, nt_hash + 16); + + _free(passwd); + _free(u_passwd); + + return memcmp(nt_hash, msg->nt_hash, 24) ? PWDB_DENIED : PWDB_SUCCESS; +} + +static int chap_check(uint8_t *ptr) +{ + return *ptr == MSCHAP_V1; +} + +static struct ppp_auth_handler_t chap = { + .name = "MSCHAP-v1", + .init = auth_data_init, + .free = auth_data_free, + .send_conf_req = lcp_send_conf_req, + .recv_conf_req = lcp_recv_conf_req, + .start = chap_start, + .finish = chap_finish, + .check = chap_check, +}; + +static void chap_recv(struct ppp_handler_t *h) +{ + struct chap_auth_data_t *d = container_of(h, typeof(*d), h); + struct chap_hdr_t *hdr = (struct chap_hdr_t *)d->ppp->chan_buf; + + if (d->ppp->chan_buf_size < sizeof(*hdr) || ntohs(hdr->len) < HDR_LEN || ntohs(hdr->len) < d->ppp->chan_buf_size - 2) { + log_ppp_warn("mschap-v1: short packet received\n"); + return; + } + + if (hdr->code == CHAP_RESPONSE) + chap_recv_response(d, hdr); + else + log_ppp_warn("mschap-v1: unknown code received %x\n", hdr->code); +} + +static void __init auth_mschap_v1_init() +{ + char *opt; + + opt = conf_get_opt("auth", "timeout"); + if (opt && atoi(opt) > 0) + conf_timeout = atoi(opt); + + opt = conf_get_opt("auth", "interval"); + if (opt && atoi(opt) > 0) + conf_interval = atoi(opt); + + opt = conf_get_opt("auth", "max-failure"); + if (opt && atoi(opt) > 0) + conf_max_failure = atoi(opt); + + urandom_fd = open("/dev/urandom", O_RDONLY); + if (urandom_fd < 0) { + log_emerg("mschap-v1: failed to open /dev/urandom: %s\n", strerror(errno)); + return; + } + if (ppp_auth_register_handler(&chap)) + log_emerg("mschap-v1: failed to register handler\n"); +} + |