diff options
Diffstat (limited to 'crypto/telnet/libtelnet/sra.c')
| -rw-r--r-- | crypto/telnet/libtelnet/sra.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/crypto/telnet/libtelnet/sra.c b/crypto/telnet/libtelnet/sra.c new file mode 100644 index 0000000..44a26f2 --- /dev/null +++ b/crypto/telnet/libtelnet/sra.c @@ -0,0 +1,478 @@ +#ifdef SRA +#include <sys/types.h> +#include <arpa/telnet.h> +#include <stdio.h> +#ifdef __STDC__ +#include <stdlib.h> +#endif +#ifdef NO_STRING_H +#include <strings.h> +#else +#include <string.h> +#endif + +#include "auth.h" +#include "misc.h" +#include "encrypt.h" +#include "pk.h" + +char pka[HEXKEYBYTES+1], ska[HEXKEYBYTES+1], pkb[HEXKEYBYTES+1]; +char *user,*pass,*xuser,*xpass; +DesData ck; +IdeaData ik; + +extern int auth_debug_mode; +static sra_valid = 0; +static passwd_sent = 0; + +static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0, + AUTHTYPE_SRA, }; + +#define SRA_KEY 0 +#define SRA_USER 1 +#define SRA_CONTINUE 2 +#define SRA_PASS 3 +#define SRA_ACCEPT 4 +#define SRA_REJECT 5 + +/* support routine to send out authentication message */ +static int Data(ap, type, d, c) +Authenticator *ap; +int type; +void *d; +int c; +{ + unsigned char *p = str_data + 4; + unsigned char *cd = (unsigned char *)d; + + if (c == -1) + c = strlen((char *)cd); + + if (auth_debug_mode) { + printf("%s:%d: [%d] (%d)", + str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY", + str_data[3], + type, c); + printd(d, c); + printf("\r\n"); + } + *p++ = ap->type; + *p++ = ap->way; + *p++ = type; + while (c-- > 0) { + if ((*p++ = *cd++) == IAC) + *p++ = IAC; + } + *p++ = IAC; + *p++ = SE; + if (str_data[3] == TELQUAL_IS) + printsub('>', &str_data[2], p - (&str_data[2])); + return(net_write(str_data, p - str_data)); +} + +int sra_init(ap, server) +Authenticator *ap; +int server; +{ + if (server) + str_data[3] = TELQUAL_REPLY; + else + str_data[3] = TELQUAL_IS; + + user = (char *)malloc(256); + xuser = (char *)malloc(512); + pass = (char *)malloc(256); + xpass = (char *)malloc(512); + passwd_sent = 0; + + genkeys(pka,ska); + return(1); +} + +/* client received a go-ahead for sra */ +int sra_send(ap) +Authenticator *ap; +{ + /* send PKA */ + + if (auth_debug_mode) + printf("Sent PKA to server.\r\n" ); + printf("Trying SRA secure login:\r\n"); + if (!Data(ap, SRA_KEY, (void *)pka, HEXKEYBYTES)) { + if (auth_debug_mode) + printf("Not enough room for authentication data\r\n"); + return(0); + } + + return(1); +} + +/* server received an IS -- could be SRA KEY, USER, or PASS */ +void sra_is(ap, data, cnt) +Authenticator *ap; +unsigned char *data; +int cnt; +{ + int valid; + Session_Key skey; + + if (cnt-- < 1) + return; + switch (*data++) { + + case SRA_KEY: + if (cnt < HEXKEYBYTES) { + Data(ap, SRA_REJECT, (void *)0, 0); + auth_finished(ap, AUTH_USER); + if (auth_debug_mode) { + printf("SRA user rejected for bad PKB\r\n"); + } + return; + } + if (auth_debug_mode) + printf("Sent pka\r\n"); + if (!Data(ap, SRA_KEY, (void *)pka, HEXKEYBYTES)) { + if (auth_debug_mode) + printf("Not enough room\r\n"); + return; + } + memcpy(pkb,data,HEXKEYBYTES); + pkb[HEXKEYBYTES] = '\0'; + common_key(ska,pkb,&ik,&ck); + break; + + case SRA_USER: + /* decode KAB(u) */ + memcpy(xuser,data,cnt); + xuser[cnt] = '\0'; + pk_decode(xuser,user,&ck); + auth_encrypt_user(user); + Data(ap, SRA_CONTINUE, (void *)0, 0); + + break; + + case SRA_PASS: + /* decode KAB(P) */ + memcpy(xpass,data,cnt); + xpass[cnt] = '\0'; + pk_decode(xpass,pass,&ck); + + /* check user's password */ + valid = check_user(user,pass); + + if(valid) { + Data(ap, SRA_ACCEPT, (void *)0, 0); +#ifdef DES_ENCRYPTION + skey.data = ck; + skey.type = SK_DES; + skey.length = 8; + encrypt_session_key(&skey, 1); +#endif + + sra_valid = 1; + auth_finished(ap, AUTH_VALID); + if (auth_debug_mode) { + printf("SRA user accepted\r\n"); + } + } + else { + Data(ap, SRA_CONTINUE, (void *)0, 0); +/* + Data(ap, SRA_REJECT, (void *)0, 0); + sra_valid = 0; + auth_finished(ap, AUTH_REJECT); +*/ + if (auth_debug_mode) { + printf("SRA user failed\r\n"); + } + } + break; + + default: + if (auth_debug_mode) + printf("Unknown SRA option %d\r\n", data[-1]); + Data(ap, SRA_REJECT, 0, 0); + sra_valid = 0; + auth_finished(ap, AUTH_REJECT); + break; + } +} + +extern char *getpass(); + +/* client received REPLY -- could be SRA KEY, CONTINUE, ACCEPT, or REJECT */ +void sra_reply(ap, data, cnt) +Authenticator *ap; +unsigned char *data; +int cnt; +{ + extern char *telnet_gets(); + char uprompt[256],tuser[256]; + Session_Key skey; + int i; + + if (cnt-- < 1) + return; + switch (*data++) { + + case SRA_KEY: + /* calculate common key */ + if (cnt < HEXKEYBYTES) { + if (auth_debug_mode) { + printf("SRA user rejected for bad PKB\r\n"); + } + return; + } + memcpy(pkb,data,HEXKEYBYTES); + pkb[HEXKEYBYTES] = '\0'; + + common_key(ska,pkb,&ik,&ck); + + enc_user: + + /* encode user */ + memset(tuser,0,sizeof(tuser)); + sprintf(uprompt,"User (%s): ",UserNameRequested); + telnet_gets(uprompt,tuser,255,1); + if (tuser[0] == '\n' || tuser[0] == '\r' ) + strcpy(user,UserNameRequested); + else { + /* telnet_gets leaves the newline on */ + for(i=0;i<sizeof(tuser);i++) { + if (tuser[i] == '\n') { + tuser[i] = '\0'; + break; + } + } + strcpy(user,tuser); + } + pk_encode(user,xuser,&ck); + + /* send it off */ + if (auth_debug_mode) + printf("Sent KAB(U)\r\n"); + if (!Data(ap, SRA_USER, (void *)xuser, strlen(xuser))) { + if (auth_debug_mode) + printf("Not enough room\r\n"); + return; + } + break; + + case SRA_CONTINUE: + if (passwd_sent) { + passwd_sent = 0; + printf("[ SRA login failed ]\r\n"); + goto enc_user; + } + /* encode password */ + memset(pass,0,sizeof(pass)); + telnet_gets("Password: ",pass,255,0); + pk_encode(pass,xpass,&ck); + /* send it off */ + if (auth_debug_mode) + printf("Sent KAB(P)\r\n"); + if (!Data(ap, SRA_PASS, (void *)xpass, strlen(xpass))) { + if (auth_debug_mode) + printf("Not enough room\r\n"); + return; + } + passwd_sent = 1; + break; + + case SRA_REJECT: + printf("[ SRA refuses authentication ]\r\n"); + printf("Trying plaintext login:\r\n"); + auth_finished(0,AUTH_REJECT); + return; + + case SRA_ACCEPT: + printf("[ SRA accepts you ]\r\n"); +#ifdef DES_ENCRYPTION + skey.data = ck; + skey.type = SK_DES; + skey.length = 8; + encrypt_session_key(&skey, 0); +#endif + + auth_finished(ap, AUTH_VALID); + return; + default: + if (auth_debug_mode) + printf("Unknown SRA option %d\r\n", data[-1]); + return; + } +} + +int sra_status(ap, name, level) +Authenticator *ap; +char *name; +int level; +{ + if (level < AUTH_USER) + return(level); + if (UserNameRequested && sra_valid) { + strcpy(name, UserNameRequested); + return(AUTH_VALID); + } else + return(AUTH_USER); +} + +#define BUMP(buf, len) while (*(buf)) {++(buf), --(len);} +#define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);} + +void sra_printsub(data, cnt, buf, buflen) +unsigned char *data, *buf; +int cnt, buflen; +{ + char lbuf[32]; + register int i; + + buf[buflen-1] = '\0'; /* make sure its NULL terminated */ + buflen -= 1; + + switch(data[3]) { + + case SRA_CONTINUE: + strncpy((char *)buf, " CONTINUE ", buflen); + goto common; + + case SRA_REJECT: /* Rejected (reason might follow) */ + strncpy((char *)buf, " REJECT ", buflen); + goto common; + + case SRA_ACCEPT: /* Accepted (name might follow) */ + strncpy((char *)buf, " ACCEPT ", buflen); + + common: + BUMP(buf, buflen); + if (cnt <= 4) + break; + ADDC(buf, buflen, '"'); + for (i = 4; i < cnt; i++) + ADDC(buf, buflen, data[i]); + ADDC(buf, buflen, '"'); + ADDC(buf, buflen, '\0'); + break; + + case SRA_KEY: /* Authentication data follows */ + strncpy((char *)buf, " KEY ", buflen); + goto common2; + + case SRA_USER: + strncpy((char *)buf, " USER ", buflen); + goto common2; + + case SRA_PASS: + strncpy((char *)buf, " PASS ", buflen); + goto common2; + + default: + sprintf(lbuf, " %d (unknown)", data[3]); + strncpy((char *)buf, lbuf, buflen); + common2: + BUMP(buf, buflen); + for (i = 4; i < cnt; i++) { + sprintf(lbuf, " %d", data[i]); + strncpy((char *)buf, lbuf, buflen); + BUMP(buf, buflen); + } + break; + } +} + +struct passwd *pw; + +/* + * Helper function for sgetpwnam(). + */ +char * +sgetsave(s) + char *s; +{ + char *new = malloc((unsigned) strlen(s) + 1); + + if (new == NULL) { + return(NULL); + } + (void) strcpy(new, s); + return (new); +} + +#include <pwd.h> +#include <syslog.h> +#ifdef USE_SHADOW +#include <shadow.h> +#endif + + +struct passwd * +sgetpwnam(name) + char *name; +{ + static struct passwd save; + register struct passwd *p; + char *sgetsave(); + + if ((p = getpwnam(name)) == NULL) + return (p); + if (save.pw_name) { + free(save.pw_name); + free(save.pw_passwd); + free(save.pw_gecos); + free(save.pw_dir); + free(save.pw_shell); + } + save = *p; + save.pw_name = sgetsave(p->pw_name); + save.pw_passwd = sgetsave(p->pw_passwd); + save.pw_gecos = sgetsave(p->pw_gecos); + save.pw_dir = sgetsave(p->pw_dir); + save.pw_shell = sgetsave(p->pw_shell); +#if 0 +syslog(LOG_WARNING,"%s\n",save.pw_name); +syslog(LOG_WARNING,"%s\n",save.pw_passwd); +syslog(LOG_WARNING,"%s\n",save.pw_gecos); +syslog(LOG_WARNING,"%s\n",save.pw_dir); +#endif +#ifdef USE_SHADOW + { + struct spwd *sp; + sp = getspnam(name); + free(save.pw_passwd); + save.pw_passwd = sgetsave(sp->sp_pwdp); + } +#endif + return (&save); +} + +char *crypt(); + +int check_user(name, pass) +char *name; +char *pass; +{ + register char *cp; + char *xpasswd, *salt; + + if (pw = sgetpwnam(name)) { + if (pw->pw_shell == NULL) { + pw = (struct passwd *) NULL; + return(0); + } + + salt = pw->pw_passwd; + xpasswd = crypt(pass, salt); + /* The strcmp does not catch null passwords! */ + if (pw == NULL || *pw->pw_passwd == '\0' || + strcmp(xpasswd, pw->pw_passwd)) { + pw = (struct passwd *) NULL; + return(0); + } + return(1); + } + return(0); +} + + +#endif + |
