| 1 | #ifndef PUTTY_SSHGSS_H |
| 2 | #define PUTTY_SSHGSS_H |
| 3 | #include "putty.h" |
| 4 | #include "pgssapi.h" |
| 5 | |
| 6 | #ifndef NO_GSSAPI |
| 7 | |
| 8 | #define SSH2_GSS_OIDTYPE 0x06 |
| 9 | typedef void *Ssh_gss_ctx; |
| 10 | |
| 11 | typedef enum Ssh_gss_stat { |
| 12 | SSH_GSS_OK = 0, |
| 13 | SSH_GSS_S_CONTINUE_NEEDED, |
| 14 | SSH_GSS_NO_MEM, |
| 15 | SSH_GSS_BAD_HOST_NAME, |
| 16 | SSH_GSS_FAILURE |
| 17 | } Ssh_gss_stat; |
| 18 | |
| 19 | #define SSH_GSS_S_COMPLETE SSH_GSS_OK |
| 20 | |
| 21 | #define SSH_GSS_CLEAR_BUF(buf) do { \ |
| 22 | (*buf).length = 0; \ |
| 23 | (*buf).value = NULL; \ |
| 24 | } while (0) |
| 25 | |
| 26 | typedef gss_buffer_desc Ssh_gss_buf; |
| 27 | typedef gss_name_t Ssh_gss_name; |
| 28 | |
| 29 | /* Functions, provided by either wingss.c or sshgssc.c */ |
| 30 | |
| 31 | struct ssh_gss_library; |
| 32 | |
| 33 | /* |
| 34 | * Prepare a collection of GSSAPI libraries for use in a single SSH |
| 35 | * connection. Returns a structure containing a list of libraries, |
| 36 | * with their ids (see struct ssh_gss_library below) filled in so |
| 37 | * that the client can go through them in the SSH user's preferred |
| 38 | * order. |
| 39 | * |
| 40 | * Must always return non-NULL. (Even if no libraries are available, |
| 41 | * it must return an empty structure.) |
| 42 | * |
| 43 | * The free function cleans up the structure, and its associated |
| 44 | * libraries (if any). |
| 45 | */ |
| 46 | struct ssh_gss_liblist { |
| 47 | struct ssh_gss_library *libraries; |
| 48 | int nlibraries; |
| 49 | }; |
| 50 | struct ssh_gss_liblist *ssh_gss_setup(Conf *conf); |
| 51 | void ssh_gss_cleanup(struct ssh_gss_liblist *list); |
| 52 | |
| 53 | /* |
| 54 | * Fills in buf with a string describing the GSSAPI mechanism in |
| 55 | * use. buf->data is not dynamically allocated. |
| 56 | */ |
| 57 | typedef Ssh_gss_stat (*t_ssh_gss_indicate_mech)(struct ssh_gss_library *lib, |
| 58 | Ssh_gss_buf *buf); |
| 59 | |
| 60 | /* |
| 61 | * Converts a name such as a hostname into a GSSAPI internal form, |
| 62 | * which is placed in "out". The result should be freed by |
| 63 | * ssh_gss_release_name(). |
| 64 | */ |
| 65 | typedef Ssh_gss_stat (*t_ssh_gss_import_name)(struct ssh_gss_library *lib, |
| 66 | char *in, Ssh_gss_name *out); |
| 67 | |
| 68 | /* |
| 69 | * Frees the contents of an Ssh_gss_name structure filled in by |
| 70 | * ssh_gss_import_name(). |
| 71 | */ |
| 72 | typedef Ssh_gss_stat (*t_ssh_gss_release_name)(struct ssh_gss_library *lib, |
| 73 | Ssh_gss_name *name); |
| 74 | |
| 75 | /* |
| 76 | * The main GSSAPI security context setup function. The "out" |
| 77 | * parameter will need to be freed by ssh_gss_free_tok. |
| 78 | */ |
| 79 | typedef Ssh_gss_stat (*t_ssh_gss_init_sec_context) |
| 80 | (struct ssh_gss_library *lib, |
| 81 | Ssh_gss_ctx *ctx, Ssh_gss_name name, int delegate, |
| 82 | Ssh_gss_buf *in, Ssh_gss_buf *out); |
| 83 | |
| 84 | /* |
| 85 | * Frees the contents of an Ssh_gss_buf filled in by |
| 86 | * ssh_gss_init_sec_context(). Do not accidentally call this on |
| 87 | * something filled in by ssh_gss_get_mic() (which requires a |
| 88 | * different free function) or something filled in by any other |
| 89 | * way. |
| 90 | */ |
| 91 | typedef Ssh_gss_stat (*t_ssh_gss_free_tok)(struct ssh_gss_library *lib, |
| 92 | Ssh_gss_buf *); |
| 93 | |
| 94 | /* |
| 95 | * Acquires the credentials to perform authentication in the first |
| 96 | * place. Needs to be freed by ssh_gss_release_cred(). |
| 97 | */ |
| 98 | typedef Ssh_gss_stat (*t_ssh_gss_acquire_cred)(struct ssh_gss_library *lib, |
| 99 | Ssh_gss_ctx *); |
| 100 | |
| 101 | /* |
| 102 | * Frees the contents of an Ssh_gss_ctx filled in by |
| 103 | * ssh_gss_acquire_cred(). |
| 104 | */ |
| 105 | typedef Ssh_gss_stat (*t_ssh_gss_release_cred)(struct ssh_gss_library *lib, |
| 106 | Ssh_gss_ctx *); |
| 107 | |
| 108 | /* |
| 109 | * Gets a MIC for some input data. "out" needs to be freed by |
| 110 | * ssh_gss_free_mic(). |
| 111 | */ |
| 112 | typedef Ssh_gss_stat (*t_ssh_gss_get_mic)(struct ssh_gss_library *lib, |
| 113 | Ssh_gss_ctx ctx, Ssh_gss_buf *in, |
| 114 | Ssh_gss_buf *out); |
| 115 | |
| 116 | /* |
| 117 | * Frees the contents of an Ssh_gss_buf filled in by |
| 118 | * ssh_gss_get_mic(). Do not accidentally call this on something |
| 119 | * filled in by ssh_gss_init_sec_context() (which requires a |
| 120 | * different free function) or something filled in by any other |
| 121 | * way. |
| 122 | */ |
| 123 | typedef Ssh_gss_stat (*t_ssh_gss_free_mic)(struct ssh_gss_library *lib, |
| 124 | Ssh_gss_buf *); |
| 125 | |
| 126 | /* |
| 127 | * Return an error message after authentication failed. The |
| 128 | * message string is returned in "buf", with buf->len giving the |
| 129 | * number of characters of printable message text and buf->data |
| 130 | * containing one more character which is a trailing NUL. |
| 131 | * buf->data should be manually freed by the caller. |
| 132 | */ |
| 133 | typedef Ssh_gss_stat (*t_ssh_gss_display_status)(struct ssh_gss_library *lib, |
| 134 | Ssh_gss_ctx, Ssh_gss_buf *buf); |
| 135 | |
| 136 | struct ssh_gss_library { |
| 137 | /* |
| 138 | * Identifying number in the enumeration used by the |
| 139 | * configuration code to specify a preference order. |
| 140 | */ |
| 141 | int id; |
| 142 | |
| 143 | /* |
| 144 | * Filled in at initialisation time, if there's anything |
| 145 | * interesting to say about how GSSAPI was initialised (e.g. |
| 146 | * which of a number of alternative libraries was used). |
| 147 | */ |
| 148 | const char *gsslogmsg; |
| 149 | |
| 150 | /* |
| 151 | * Function pointers implementing the SSH wrapper layer on top |
| 152 | * of GSSAPI. (Defined in sshgssc, typically, though Windows |
| 153 | * provides an alternative layer to sit on top of the annoyingly |
| 154 | * different SSPI.) |
| 155 | */ |
| 156 | t_ssh_gss_indicate_mech indicate_mech; |
| 157 | t_ssh_gss_import_name import_name; |
| 158 | t_ssh_gss_release_name release_name; |
| 159 | t_ssh_gss_init_sec_context init_sec_context; |
| 160 | t_ssh_gss_free_tok free_tok; |
| 161 | t_ssh_gss_acquire_cred acquire_cred; |
| 162 | t_ssh_gss_release_cred release_cred; |
| 163 | t_ssh_gss_get_mic get_mic; |
| 164 | t_ssh_gss_free_mic free_mic; |
| 165 | t_ssh_gss_display_status display_status; |
| 166 | |
| 167 | /* |
| 168 | * Additional data for the wrapper layers. |
| 169 | */ |
| 170 | union { |
| 171 | struct gssapi_functions gssapi; |
| 172 | /* |
| 173 | * The SSPI wrappers don't need to store their Windows API |
| 174 | * function pointers in this structure, because there can't |
| 175 | * be more than one set of them available. |
| 176 | */ |
| 177 | } u; |
| 178 | |
| 179 | /* |
| 180 | * Wrapper layers will often also need to store a library handle |
| 181 | * of some sort for cleanup time. |
| 182 | */ |
| 183 | void *handle; |
| 184 | }; |
| 185 | |
| 186 | #endif /* NO_GSSAPI */ |
| 187 | |
| 188 | #endif /*PUTTY_SSHGSS_H*/ |