diff options
| -rw-r--r-- | file.c | 176 |
1 files changed, 156 insertions, 20 deletions
@@ -70,25 +70,32 @@ struct rpc_file_exec_context { static struct blob_buf buf; +static char *canonpath; enum { RPC_F_R_PATH, + RPC_F_R_SESSION, __RPC_F_R_MAX, }; static const struct blobmsg_policy rpc_file_r_policy[__RPC_F_R_MAX] = { - [RPC_F_R_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, + [RPC_F_R_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, + [RPC_F_R_SESSION] = { .name = "ubus_rpc_session", + .type = BLOBMSG_TYPE_STRING }, }; enum { RPC_F_RB_PATH, RPC_F_RB_BASE64, + RPC_F_RB_SESSION, __RPC_F_RB_MAX, }; static const struct blobmsg_policy rpc_file_rb_policy[__RPC_F_RB_MAX] = { - [RPC_F_RB_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, - [RPC_F_RB_BASE64] = { .name = "base64", .type = BLOBMSG_TYPE_BOOL }, + [RPC_F_RB_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, + [RPC_F_RB_BASE64] = { .name = "base64", .type = BLOBMSG_TYPE_BOOL }, + [RPC_F_RB_SESSION] = { .name = "ubus_rpc_session", + .type = BLOBMSG_TYPE_STRING }, }; enum { @@ -97,28 +104,34 @@ enum { RPC_F_RW_APPEND, RPC_F_RW_MODE, RPC_F_RW_BASE64, + RPC_F_RW_SESSION, __RPC_F_RW_MAX, }; static const struct blobmsg_policy rpc_file_rw_policy[__RPC_F_RW_MAX] = { - [RPC_F_RW_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, - [RPC_F_RW_DATA] = { .name = "data", .type = BLOBMSG_TYPE_STRING }, - [RPC_F_RW_APPEND] = { .name = "append", .type = BLOBMSG_TYPE_BOOL }, - [RPC_F_RW_MODE] = { .name = "mode", .type = BLOBMSG_TYPE_INT32 }, - [RPC_F_RW_BASE64] = { .name = "base64", .type = BLOBMSG_TYPE_BOOL }, + [RPC_F_RW_PATH] = { .name = "path", .type = BLOBMSG_TYPE_STRING }, + [RPC_F_RW_DATA] = { .name = "data", .type = BLOBMSG_TYPE_STRING }, + [RPC_F_RW_APPEND] = { .name = "append", .type = BLOBMSG_TYPE_BOOL }, + [RPC_F_RW_MODE] = { .name = "mode", .type = BLOBMSG_TYPE_INT32 }, + [RPC_F_RW_BASE64] = { .name = "base64", .type = BLOBMSG_TYPE_BOOL }, + [RPC_F_RW_SESSION] = { .name = "ubus_rpc_session", + .type = BLOBMSG_TYPE_STRING }, }; enum { RPC_E_CMD, RPC_E_PARM, RPC_E_ENV, + RPC_E_SESSION, __RPC_E_MAX, }; static const struct blobmsg_policy rpc_exec_policy[__RPC_E_MAX] = { - [RPC_E_CMD] = { .name = "command", .type = BLOBMSG_TYPE_STRING }, - [RPC_E_PARM] = { .name = "params", .type = BLOBMSG_TYPE_ARRAY }, - [RPC_E_ENV] = { .name = "env", .type = BLOBMSG_TYPE_TABLE }, + [RPC_E_CMD] = { .name = "command", .type = BLOBMSG_TYPE_STRING }, + [RPC_E_PARM] = { .name = "params", .type = BLOBMSG_TYPE_ARRAY }, + [RPC_E_ENV] = { .name = "env", .type = BLOBMSG_TYPE_TABLE }, + [RPC_E_SESSION] = { .name = "ubus_rpc_session", + .type = BLOBMSG_TYPE_STRING }, }; static const char *d_types[] = { @@ -155,6 +168,94 @@ rpc_errno_status(void) } } +static bool +rpc_file_read_access(const struct blob_attr *sid, const char *path) +{ + if (!sid) + return true; + + return ops->session_access(blobmsg_data(sid), "file", path, "read"); +} + +static bool +rpc_file_write_access(const struct blob_attr *sid, const char *path) +{ + if (!sid) + return true; + + return ops->session_access(blobmsg_data(sid), "file", path, "write"); +} + +static bool +rpc_file_exec_access(const struct blob_attr *sid, const char *path) +{ + if (!sid) + return true; + + return ops->session_access(blobmsg_data(sid), "file", path, "exec"); +} + +static char * +rpc_canonicalize_path(const char *path) +{ + char *cp; + const char *p; + + if (path == NULL || *path == '\0') + return NULL; + + if (canonpath != NULL) + free(canonpath); + + canonpath = strdup(path); + + if (canonpath == NULL) + return NULL; + + /* normalize */ + for (cp = canonpath, p = path; *p != '\0'; ) { + if (*p != '/') + goto next; + + /* skip repeating / */ + if (p[1] == '/') { + p++; + continue; + } + + /* /./ or /../ */ + if (p[1] == '.') { + /* skip /./ */ + if ((p[2] == '\0') || (p[2] == '/')) { + p += 2; + continue; + } + + /* collapse /x/../ */ + if ((p[2] == '.') && ((p[3] == '\0') || (p[3] == '/'))) { + while ((cp > canonpath) && (*--cp != '/')) + ; + + p += 3; + continue; + } + } + +next: + *cp++ = *p++; + } + + /* remove trailing slash if not root / */ + if ((cp > canonpath + 1) && (cp[-1] == '/')) + cp--; + else if (cp == canonpath) + *cp++ = '/'; + + *cp = '\0'; + + return canonpath; +} + static struct blob_attr ** rpc_check_path(struct blob_attr *msg, char **path, struct stat *s) { @@ -168,7 +269,19 @@ rpc_check_path(struct blob_attr *msg, char **path, struct stat *s) return NULL; } - *path = blobmsg_data(tb[RPC_F_R_PATH]); + *path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_R_PATH])); + + if (*path == NULL) + { + errno = ENOMEM; + return NULL; + } + + if (!rpc_file_read_access(tb[RPC_F_R_SESSION], *path)) + { + errno = EACCES; + return NULL; + } if (stat(*path, s)) return NULL; @@ -194,7 +307,13 @@ rpc_file_read(struct ubus_context *ctx, struct ubus_object *obj, if (!tb[RPC_F_RB_PATH]) return rpc_errno_status(); - path = blobmsg_data(tb[RPC_F_RB_PATH]); + path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_RB_PATH])); + + if (path == NULL) + return UBUS_STATUS_UNKNOWN_ERROR; + + if (!rpc_file_read_access(tb[RPC_F_RB_SESSION], path)) + return UBUS_STATUS_PERMISSION_DENIED; if (stat(path, &s)) return rpc_errno_status(); @@ -271,6 +390,7 @@ rpc_file_write(struct ubus_context *ctx, struct ubus_object *obj, int append = O_TRUNC; mode_t prev_mode, mode = 0666; int fd, rv = 0; + char *path = NULL; void *data = NULL; ssize_t data_len = 0; @@ -280,6 +400,14 @@ rpc_file_write(struct ubus_context *ctx, struct ubus_object *obj, if (!tb[RPC_F_RW_PATH] || !tb[RPC_F_RW_DATA]) return UBUS_STATUS_INVALID_ARGUMENT; + path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_RW_PATH])); + + if (path == NULL) + return UBUS_STATUS_UNKNOWN_ERROR; + + if (!rpc_file_write_access(tb[RPC_F_RW_SESSION], path)) + return UBUS_STATUS_PERMISSION_DENIED; + data = blobmsg_data(tb[RPC_F_RW_DATA]); data_len = blobmsg_data_len(tb[RPC_F_RW_DATA]) - 1; @@ -290,7 +418,7 @@ rpc_file_write(struct ubus_context *ctx, struct ubus_object *obj, mode = blobmsg_get_u32(tb[RPC_F_RW_MODE]); prev_mode = umask(0); - fd = open(blobmsg_data(tb[RPC_F_RW_PATH]), O_CREAT | O_WRONLY | append, mode); + fd = open(path, O_CREAT | O_WRONLY | append, mode); umask(prev_mode); if (fd < 0) return rpc_errno_status(); @@ -615,7 +743,7 @@ rpc_fdclose(int fd) } static int -rpc_file_exec_run(const char *cmd, +rpc_file_exec_run(const char *cmd, const struct blob_attr *sid, const struct blob_attr *arg, const struct blob_attr *env, struct ubus_context *ctx, struct ubus_request_data *req) { @@ -629,7 +757,7 @@ rpc_file_exec_run(const char *cmd, struct blob_attr *cur; uint8_t arglen; - char **args, **tmp; + char *executable, **args, **tmp; struct rpc_file_exec_context *c; @@ -638,6 +766,14 @@ rpc_file_exec_run(const char *cmd, if (!cmd) return UBUS_STATUS_NOT_FOUND; + executable = rpc_canonicalize_path(cmd); + + if (executable == NULL) + return UBUS_STATUS_UNKNOWN_ERROR; + + if (!rpc_file_exec_access(sid, executable)) + return UBUS_STATUS_PERMISSION_DENIED; + c = malloc(sizeof(*c)); if (!c) @@ -675,7 +811,7 @@ rpc_file_exec_run(const char *cmd, if (!args) return UBUS_STATUS_UNKNOWN_ERROR; - args[0] = (char *)cmd; + args[0] = (char *)executable; args[1] = NULL; if (arg) @@ -717,7 +853,7 @@ rpc_file_exec_run(const char *cmd, } } - if (execv(cmd, args)) + if (execv(executable, args)) return rpc_errno_status(); default: @@ -756,8 +892,8 @@ rpc_file_exec(struct ubus_context *ctx, struct ubus_object *obj, if (!tb[RPC_E_CMD]) return UBUS_STATUS_INVALID_ARGUMENT; - return rpc_file_exec_run(blobmsg_data(tb[RPC_E_CMD]), - tb[RPC_E_PARM], tb[RPC_E_ENV], ctx, req); + return rpc_file_exec_run(blobmsg_data(tb[RPC_E_CMD]), tb[RPC_E_SESSION], + tb[RPC_E_PARM], tb[RPC_E_ENV], ctx, req); } |