diff options
Diffstat (limited to 'src/reclaim/pabc_helper.c')
-rw-r--r-- | src/reclaim/pabc_helper.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/src/reclaim/pabc_helper.c b/src/reclaim/pabc_helper.c new file mode 100644 index 000000000..1b1dbea0f --- /dev/null +++ b/src/reclaim/pabc_helper.c @@ -0,0 +1,364 @@ +// maximilian.kaul@aisec.fraunhofer.de + +// WIP implementation of +// https://github.com/ontio/ontology-crypto/wiki/Anonymous-Credential +// using the relic library https://github.com/relic-toolkit/relic/ + +#include "pabc_helper.h" +#include <pwd.h> +#include <stdlib.h> +#include <unistd.h> + +static char pabc_dir[PATH_MAX + 1]; + +static const char * +get_homedir () +{ + const char *homedir; + if ((homedir = getenv ("HOME")) == NULL) + { + homedir = getpwuid (getuid ())->pw_dir; + } + return homedir; +} + + +static enum GNUNET_GenericReturnValue +write_file (char const *const filename, const char *buffer) +{ + struct GNUNET_DISK_FileHandle *fh; + fh = GNUNET_DISK_file_open (filename, + GNUNET_DISK_OPEN_WRITE + | GNUNET_DISK_OPEN_TRUNCATE + | GNUNET_DISK_OPEN_CREATE, + GNUNET_DISK_PERM_USER_WRITE + | GNUNET_DISK_PERM_USER_READ); + if (fh == NULL) + return GNUNET_SYSERR; + if (GNUNET_SYSERR == GNUNET_DISK_file_write (fh, + buffer, strlen (buffer) + 1)) + goto fail; + GNUNET_DISK_file_close (fh); + return GNUNET_OK; + +fail: + GNUNET_DISK_file_close (fh); + return GNUNET_SYSERR; +} + + +static enum GNUNET_GenericReturnValue +init_pabc_dir () +{ + size_t filename_size = strlen (get_homedir ()) + 1 + strlen (".local") + 1 + + strlen ("pabc-reclaim") + 1; + snprintf (pabc_dir, filename_size, "%s/%s/%s", + get_homedir (), ".local", "pabc-reclaim"); + return GNUNET_DISK_directory_create (pabc_dir); +} + + +static const char * +get_pabcdir () +{ + init_pabc_dir (); + return pabc_dir; +} + + +enum GNUNET_GenericReturnValue +read_file (char const *const filename, char **buffer) +{ + struct GNUNET_DISK_FileHandle *fh; + if (GNUNET_YES != GNUNET_DISK_file_test (filename)) + return GNUNET_SYSERR; + + fh = GNUNET_DISK_file_open (filename, + GNUNET_DISK_OPEN_READ, + GNUNET_DISK_PERM_USER_READ); + if (fh == NULL) + return GNUNET_SYSERR; + long lSize = GNUNET_DISK_file_seek (fh, 0, GNUNET_DISK_SEEK_END); + if (lSize < 0) + goto fail; + GNUNET_DISK_file_seek (fh, 0, GNUNET_DISK_SEEK_SET); + *buffer = calloc ((size_t) lSize + 1, sizeof(char)); + if (*buffer == NULL) + goto fail; + + // copy the file into the buffer: + size_t r = GNUNET_DISK_file_read (fh, *buffer, (size_t) lSize); + if (r != (size_t) lSize) + goto fail; + + GNUNET_DISK_file_close (fh); + return GNUNET_OK; + +fail: + GNUNET_DISK_file_close (fh); + return GNUNET_SYSERR; +} + + +struct pabc_public_parameters * +PABC_read_issuer_ppfile (const char *f, struct pabc_context *const ctx) +{ + if (NULL == ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No global context provided\n"); + return NULL; + } + struct pabc_public_parameters *pp; + char *buffer; + int r; + r = read_file (f, &buffer); + if (GNUNET_OK != r) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Error reading file\n"); + return NULL; + } + if (PABC_OK != pabc_decode_and_new_public_parameters (ctx, &pp, buffer)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to decode public parameters\n"); + PABC_FREE_NULL (buffer); + return NULL; + } + PABC_FREE_NULL (buffer); + return pp; +} + + +enum GNUNET_GenericReturnValue +PABC_load_public_parameters (struct pabc_context *const ctx, + char const *const pp_name, + struct pabc_public_parameters **pp) +{ + char fname[PATH_MAX]; + char *pp_filename; + const char *pdir = get_pabcdir (); + + if (ctx == NULL) + return GNUNET_SYSERR; + if (pp_name == NULL) + return GNUNET_SYSERR; + + GNUNET_STRINGS_urlencode (pp_name, strlen (pp_name), &pp_filename); + if (GNUNET_YES != GNUNET_DISK_directory_test (pdir, GNUNET_YES)) + { + GNUNET_free (pp_filename); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Error reading %s\n", pdir); + return GNUNET_SYSERR; + } + snprintf (fname, PATH_MAX, "%s/%s%s", pdir, pp_filename, PABC_PP_EXT); + if (GNUNET_YES != GNUNET_DISK_file_test (fname)) + { + GNUNET_free (pp_filename); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Error testing %s\n", fname); + return GNUNET_SYSERR; + } + *pp = PABC_read_issuer_ppfile (fname, ctx); + if (*pp) + return GNUNET_OK; + else + return GNUNET_SYSERR; +} + + +enum GNUNET_GenericReturnValue +PABC_write_public_parameters (char const *const pp_name, + struct pabc_public_parameters *const pp) +{ + char *json; + char *filename; + char *pp_filename; + enum pabc_status status; + struct pabc_context *ctx = NULL; + + GNUNET_STRINGS_urlencode (pp_name, strlen (pp_name), &pp_filename); + PABC_ASSERT (pabc_new_ctx (&ctx)); + // store in json file + status = pabc_encode_public_parameters (ctx, pp, &json); + if (status != PABC_OK) + { + GNUNET_free (pp_filename); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to encode public parameters.\n"); + pabc_free_ctx (&ctx); + return GNUNET_SYSERR; + } + + size_t filename_size = + strlen (get_pabcdir ()) + 1 + strlen (pp_filename) + strlen (PABC_PP_EXT) + + 1; + filename = GNUNET_malloc (filename_size); + if (! filename) + { + GNUNET_free (pp_filename); + PABC_FREE_NULL (json); + pabc_free_ctx (&ctx); + return GNUNET_SYSERR; + } + snprintf (filename, filename_size, "%s/%s%s", get_pabcdir (), pp_filename, + PABC_PP_EXT); + + GNUNET_free (pp_filename); + if (GNUNET_OK != write_file (filename, json)) + { + PABC_FREE_NULL (filename); + PABC_FREE_NULL (json); + pabc_free_ctx (&ctx); + return GNUNET_SYSERR; + } + PABC_FREE_NULL (filename); + PABC_FREE_NULL (json); + pabc_free_ctx (&ctx); + return GNUNET_OK; +} + + +enum GNUNET_GenericReturnValue +PABC_write_usr_ctx (char const *const usr_name, + char const *const pp_name, + struct pabc_context const *const ctx, + struct pabc_public_parameters const *const pp, + struct pabc_user_context *const usr_ctx) +{ + + char *pp_filename; + char *json = NULL; + enum pabc_status status; + char *fname = NULL; + + if (NULL == usr_name) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No issuer given.\n"); + return GNUNET_SYSERR; + } + if (NULL == pp_name) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No user given.\n"); + return GNUNET_SYSERR; + } + if (NULL == ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No context given.\n"); + return GNUNET_SYSERR; + } + if (NULL == pp) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No public parameters given.\n"); + return GNUNET_SYSERR; + } + if (NULL == usr_ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No user context given.\n"); + return GNUNET_SYSERR; + } + + GNUNET_STRINGS_urlencode (pp_name, strlen (pp_name), &pp_filename); + status = pabc_encode_user_ctx (ctx, pp, usr_ctx, &json); + if (PABC_OK != status) + { + GNUNET_free (pp_filename); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Failed to encode user context.\n"); + return status; + } + + size_t fname_size = strlen (get_pabcdir ()) + 1 + strlen (usr_name) + 1 + + strlen (pp_filename) + strlen (PABC_USR_EXT) + 1; + fname = GNUNET_malloc (fname_size); + + snprintf (fname, fname_size, "%s/%s_%s%s", get_pabcdir (), usr_name, + pp_filename, + PABC_USR_EXT); + + GNUNET_free (pp_filename); + if (GNUNET_OK == write_file (fname, json)) + { + GNUNET_free (fname); + GNUNET_free (json); + return GNUNET_OK; + } + else + { + GNUNET_free (fname); + GNUNET_free (json); + return GNUNET_SYSERR; + } +} + + +enum GNUNET_GenericReturnValue +PABC_read_usr_ctx (char const *const usr_name, + char const *const pp_name, + struct pabc_context const *const ctx, + struct pabc_public_parameters const *const pp, + struct pabc_user_context **usr_ctx) +{ + char *json = NULL; + char *pp_filename; + enum pabc_status status; + + char *fname = NULL; + + if (NULL == usr_name) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No issuer given.\n"); + return GNUNET_SYSERR; + } + if (NULL == pp_name) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No user given.\n"); + return GNUNET_SYSERR; + } + if (NULL == ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No context given.\n"); + return GNUNET_SYSERR; + } + if (NULL == pp) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No public parameters given.\n"); + return GNUNET_SYSERR; + } + if (NULL == usr_ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No user context given.\n"); + return GNUNET_SYSERR; + } + GNUNET_STRINGS_urlencode (pp_name, strlen (pp_name), &pp_filename); + + size_t fname_size = strlen (get_pabcdir ()) + 1 + strlen (usr_name) + 1 + + strlen (pp_filename) + strlen (PABC_USR_EXT) + 1; + fname = GNUNET_malloc (fname_size); + snprintf (fname, fname_size, "%s/%s_%s%s", get_pabcdir (), usr_name, + pp_filename, + PABC_USR_EXT); + GNUNET_free (pp_filename); + if (GNUNET_OK != read_file (fname, &json)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to read `%s'\n", fname); + PABC_FREE_NULL (fname); + return GNUNET_SYSERR; + } + GNUNET_free (fname); + + status = pabc_new_user_context (ctx, pp, usr_ctx); + if (PABC_OK != status) + { + GNUNET_free (json); + return GNUNET_SYSERR; + } + status = pabc_decode_user_ctx (ctx, pp, *usr_ctx, json); + GNUNET_free (json); + if (PABC_OK != status) + { + pabc_free_user_context (ctx, pp, usr_ctx); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Failed to encode user context.\n"); + return GNUNET_SYSERR; + } + + return GNUNET_OK; +} |