Initial revision

1 files changed, 149 insertions, 0 deletions

diff --git a/auth-skey.c b/auth-skey.c
new file mode 100644
index 000000000..9ec170494
--- /dev/null
+++ b/auth-skey.c
@@ -0,0 +1,149 @@
+#include "includes.h"
+RCSID("$Id: auth-skey.c,v 1.2 1999/10/16 20:57:52 deraadt Exp $");
+
+#include "ssh.h"
+#include <sha1.h>
+
+/* from %OpenBSD: skeylogin.c,v 1.32 1999/08/16 14:46:56 millert Exp % */
+
+
+#define ROUND(x)   (((x)[0] << 24) + (((x)[1]) << 16) + (((x)[2]) << 8) + \
+                    ((x)[3]))
+
+/*
+ * hash_collapse()
+ */
+static u_int32_t
+hash_collapse(s)
+        u_char *s;
+{
+        int len, target;
+        u_int32_t i;
+        
+        if ((strlen(s) % sizeof(u_int32_t)) == 0)
+                target = strlen(s);    /* Multiple of 4 */
+        else
+                target = strlen(s) - (strlen(s) % sizeof(u_int32_t));
+  
+        for (i = 0, len = 0; len < target; len += 4)
+                i ^= ROUND(s + len);
+
+        return i;
+}
+char *
+skey_fake_keyinfo(char *username)
+{
+        int i;
+        u_int ptr;
+        u_char hseed[SKEY_MAX_SEED_LEN], flg = 1, *up;
+        char pbuf[SKEY_MAX_PW_LEN+1];
+        static char skeyprompt[SKEY_MAX_CHALLENGE+1];
+        char *secret = NULL;
+        size_t secretlen = 0;
+        SHA1_CTX ctx;
+        char *p, *u;
+
+        /*
+         * Base first 4 chars of seed on hostname.
+         * Add some filler for short hostnames if necessary.
+         */
+        if (gethostname(pbuf, sizeof(pbuf)) == -1)
+                *(p = pbuf) = '.';
+        else
+                for (p = pbuf; *p && isalnum(*p); p++)
+                        if (isalpha(*p) && isupper(*p))
+                                *p = tolower(*p);
+        if (*p && pbuf - p < 4)
+                (void)strncpy(p, "asjd", 4 - (pbuf - p));
+        pbuf[4] = '\0';
+
+        /* Hash the username if possible */
+        if ((up = SHA1Data(username, strlen(username), NULL)) != NULL) {
+                struct stat sb;
+                time_t t;
+                int fd;
+
+                /* Collapse the hash */
+                ptr = hash_collapse(up);
+                memset(up, 0, strlen(up));
+
+                /* See if the random file's there, else use ctime */
+                if ((fd = open(_SKEY_RAND_FILE_PATH_, O_RDONLY)) != -1
+                    && fstat(fd, &sb) == 0 &&
+                    sb.st_size > (off_t)SKEY_MAX_SEED_LEN &&
+                    lseek(fd, ptr % (sb.st_size - SKEY_MAX_SEED_LEN),
+                    SEEK_SET) != -1 && read(fd, hseed,
+                    SKEY_MAX_SEED_LEN) == SKEY_MAX_SEED_LEN) {
+                        close(fd);
+                        secret = hseed;
+                        secretlen = SKEY_MAX_SEED_LEN;
+                        flg = 0;
+                } else if (!stat(_PATH_MEM, &sb) || !stat("/", &sb)) {
+                        t = sb.st_ctime;
+                        secret = ctime(&t);
+                        secretlen = strlen(secret);
+                        flg = 0;
+                }
+        }
+
+        /* Put that in your pipe and smoke it */
+        if (flg == 0) {
+                /* Hash secret value with username */
+                SHA1Init(&ctx);
+                SHA1Update(&ctx, secret, secretlen);
+                SHA1Update(&ctx, username, strlen(username));
+                SHA1End(&ctx, up);
+                
+                /* Zero out */
+                memset(secret, 0, secretlen);
+
+                /* Now hash the hash */
+                SHA1Init(&ctx);
+                SHA1Update(&ctx, up, strlen(up));
+                SHA1End(&ctx, up);
+                
+                ptr = hash_collapse(up + 4);
+                
+                for (i = 4; i < 9; i++) {
+                        pbuf[i] = (ptr % 10) + '0';
+                        ptr /= 10;
+                }
+                pbuf[i] = '\0';
+
+                /* Sequence number */
+                ptr = ((up[2] + up[3]) % 99) + 1;
+
+                memset(up, 0, 20); /* SHA1 specific */
+                free(up);
+
+                (void)snprintf(skeyprompt, sizeof skeyprompt,
+                              "otp-%.*s %d %.*s",
+                              SKEY_MAX_HASHNAME_LEN,
+                              skey_get_algorithm(),
+                              ptr, SKEY_MAX_SEED_LEN,
+                              pbuf);
+        } else {
+                /* Base last 8 chars of seed on username */
+                u = username;
+                i = 8;
+                p = &pbuf[4];
+                do {
+                        if (*u == 0) {
+                                /* Pad remainder with zeros */
+                                while (--i >= 0)
+                                        *p++ = '0';
+                                break;
+                        }
+
+                        *p++ = (*u++ % 10) + '0';
+                } while (--i != 0);
+                pbuf[12] = '\0';
+
+                (void)snprintf(skeyprompt, sizeof skeyprompt,
+                              "otp-%.*s %d %.*s",
+                              SKEY_MAX_HASHNAME_LEN,
+                              skey_get_algorithm(),
+                              99, SKEY_MAX_SEED_LEN, pbuf);
+        }
+        return skeyprompt;
+}