/* srv9p/static9p.c - Serve static files over 9P * * Copyright (C) 2024 Luke T. Shumaker * SPDX-Licence-Identifier: AGPL-3.0-or-later */ #include #include #include "static9p.h" #define UNUSED(name) /* name __attribute__((unused)) */ #define p9_str(cstr) ((struct lib9p_s){ .len = strlen(cstr), .utf8 = cstr }) #define p9_nulstr ((struct lib9p_s){ .len = 0, .utf8 = NULL }) /* common *********************************************************************/ static implements_lib9p_srv_file *static_common_clone(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) { _static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self); assert(self); assert(ctx); return self; } static void static_common_free(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) { _static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self); assert(self); assert(ctx); /* do nothing */ } static uint32_t static_common_io(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, lib9p_o_t UNUSED(flags)) { _static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self); assert(self); assert(ctx); return 0; } static void static_common_wstat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, struct lib9p_stat UNUSED(new)) { _static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self); assert(self); assert(ctx); lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem"); } static void static_common_remove(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) { _static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self); assert(self); assert(ctx); lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem"); } /* dir ************************************************************************/ static struct lib9p_stat static_dir_stat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) { struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self); assert(self); assert(ctx); return (struct lib9p_stat){ .kern_type = 0, .kern_dev = 0, .file_qid = { .type = LIB9P_QT_DIR, .vers = 1, .path = self->pathnum, }, .file_mode = LIB9P_DM_DIR | (self->perm & 0555), .file_atime = self->atime, .file_mtime = self->mtime, .file_size = 0, .file_name = p9_str(self->name), .file_owner_uid = p9_str(self->u_name), .file_owner_gid = p9_str(self->g_name), .file_last_modified_uid = p9_str(self->m_name), .file_extension = p9_nulstr, .file_owner_n_uid = self->u_num, .file_owner_n_gid = self->g_num, .file_last_modified_n_uid = self->m_num, }; } static implements_lib9p_srv_file *static_dir_dopen(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, char *childname) { struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self); assert(self); assert(ctx); for (size_t i = 0; self->members[i]; i++) { implements_lib9p_srv_file *filep = self->members[i]; struct lib9p_stat stat = VCALL(filep, stat, ctx); if (lib9p_ctx_has_error(&ctx->basectx)) break; lib9p_assert_stat(stat); if (strcmp(stat.file_name.utf8, childname) == 0) return filep; } lib9p_error(&ctx->basectx, LINUX_ENOENT, "no such file or directory"); return NULL; } static implements_lib9p_srv_file *static_dir_dcreate(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, char *UNUSED(childname), lib9p_dm_t UNUSED(perm), lib9p_o_t UNUSED(flags)) { struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self); assert(self); assert(ctx); lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem"); return NULL; } static size_t static_dir_dread(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, uint8_t *buf, uint32_t byte_count, size_t _obj_offset) { struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self); assert(self); assert(ctx); uint32_t byte_offset = 0; size_t obj_offset = _obj_offset; while (self->members[obj_offset]) { implements_lib9p_srv_file *filep = self->members[obj_offset]; struct lib9p_stat stat = VCALL(filep, stat, ctx); if (lib9p_ctx_has_error(&ctx->basectx)) break; lib9p_assert_stat(stat); uint32_t nbytes = lib9p_marshal_stat(&ctx->basectx, byte_count-byte_offset, &stat, &buf[byte_offset]); if (!nbytes) { if (obj_offset == _obj_offset) lib9p_error(&ctx->basectx, LINUX_ERANGE, "stat object does not fit into negotiated max message size"); break; } byte_offset += nbytes; obj_offset++; } return obj_offset - _obj_offset; } struct lib9p_srv_file_vtable static_dir_vtable = { .clone = static_common_clone, .free = static_common_free, .io = static_common_io, .stat = static_dir_stat, .wstat = static_common_wstat, .remove = static_common_remove, .dopen = static_dir_dopen, .dcreate = static_dir_dcreate, .dread = static_dir_dread, }; /* file ***********************************************************************/ static inline size_t static_file_size(struct static_file *file) { assert(file); #if __x86_64__ assert(file->data_start); #endif if (!file->data_end) return file->data_size; return (size_t)((uintptr_t)file->data_end - (uintptr_t)file->data_start); } static struct lib9p_stat static_file_stat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) { struct static_file *self = VCALL_SELF(struct static_file, implements_lib9p_srv_file, _self); assert(self); assert(ctx); return (struct lib9p_stat){ .kern_type = 0, .kern_dev = 0, .file_qid = { .type = LIB9P_QT_FILE, .vers = 1, .path = self->pathnum, }, .file_mode = self->perm & 0444, .file_atime = self->atime, .file_mtime = self->mtime, .file_size = (uint64_t)static_file_size(self), .file_name = p9_str(self->name), .file_owner_uid = p9_str(self->u_name), .file_owner_gid = p9_str(self->g_name), .file_last_modified_uid = p9_str(self->m_name), .file_extension = p9_nulstr, .file_owner_n_uid = self->u_num, .file_owner_n_gid = self->g_num, .file_last_modified_n_uid = self->m_num, }; } static uint32_t static_file_pread(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, void *buf, uint32_t byte_count, uint64_t byte_offset) { struct static_file *self = VCALL_SELF(struct static_file, implements_lib9p_srv_file, _self); assert(self); assert(ctx); size_t data_size = static_file_size(self); if (byte_offset > (uint64_t)data_size) { lib9p_error(&ctx->basectx, LINUX_EINVAL, "offset is past end-of-file length"); return 0; } size_t beg_off = (size_t)byte_offset; size_t end_off = beg_off + (size_t)byte_count; if (end_off > data_size) end_off = data_size; memcpy(buf, &self->data_start[beg_off], end_off-beg_off); return (uint32_t)(end_off-beg_off); } struct lib9p_srv_file_vtable static_file_vtable = { .clone = static_common_clone, .free = static_common_free, .io = static_common_io, .stat = static_file_stat, .wstat = static_common_wstat, .remove = static_common_remove, .pread = static_file_pread, .pwrite = NULL, };