diff options
-rw-r--r-- | common/gluten.h | 8 | ||||
-rw-r--r-- | cooker/call.c | 10 | ||||
-rw-r--r-- | cooker/calls/net.c | 92 | ||||
-rw-r--r-- | cooker/emit.c | 52 | ||||
-rw-r--r-- | cooker/emit.h | 7 | ||||
-rw-r--r-- | cooker/match.c | 169 | ||||
-rw-r--r-- | demo/iptables.hjson | 214 | ||||
-rw-r--r-- | demo/nft.hjson | 221 | ||||
-rw-r--r-- | operations.c | 149 |
9 files changed, 832 insertions, 90 deletions
diff --git a/common/gluten.h b/common/gluten.h index d06362a..4e1c249 100644 --- a/common/gluten.h +++ b/common/gluten.h @@ -222,6 +222,12 @@ struct op_iovload { struct gluten_offset iovlen; struct gluten_offset dst; size_t size; + size_t zero_fill; +}; + +struct vec_desc { + struct gluten_offset start; + off_t len_offset; }; enum op_cmp_type { @@ -238,6 +244,7 @@ extern const char *cmp_type_str[CMP_MAX + 1]; struct cmp_desc { enum op_cmp_type cmp; size_t size; + struct vec_desc vec; struct gluten_offset x; struct gluten_offset y; struct gluten_offset jmp; @@ -258,6 +265,7 @@ extern const char *bitwise_type_str[BITWISE_MAX + 1]; struct bitwise_desc { size_t size; enum bitwise_type type; + struct vec_desc vec; struct gluten_offset dst; struct gluten_offset x; struct gluten_offset y; diff --git a/cooker/call.c b/cooker/call.c index dbdc52b..19a7b7e 100644 --- a/cooker/call.c +++ b/cooker/call.c @@ -77,8 +77,8 @@ static union value parse_metadata(struct gluten_ctx *g, struct field *f, } else if ((*base_offset)->type == OFFSET_NULL || (f->flags & WBUF)) { **base_offset = tag_offset; } else if (f->flags & MASK || add) { - emit_bitwise(g, f->type, BITWISE_OR, offset, offset, - tag_offset); + emit_bitwise(g, f->type, NULL, BITWISE_OR, + offset, offset, tag_offset); } else { emit_copy_field(g, f, offset, tag_offset); } @@ -337,6 +337,9 @@ bool arg_needs_temp(struct field *f, int pos, JSON_Value *jvalue, if (json_object_get_string(tmp, "set")) return true; + if (json_object_get_string(tmp, "get") && f->flags & FD) + return true; + if (level) return true; @@ -603,6 +606,9 @@ void handle_calls(struct gluten_ctx *g, JSON_Value *value) } name = json_object_get_name(obj, n); + if (!name) + continue; + value = json_object_get_value_at(obj, n); args = json_object_get_object(obj, name); diff --git a/cooker/calls/net.c b/cooker/calls/net.c index 94b13cd..0688467 100644 --- a/cooker/calls/net.c +++ b/cooker/calls/net.c @@ -65,22 +65,23 @@ static struct num socket_flags[] = { }; static struct num protocols[] = { - { "ip", IPPROTO_IP }, - { "icmp", IPPROTO_ICMP }, - { "igmp", IPPROTO_IGMP }, - { "tcp", IPPROTO_TCP }, - { "udp", IPPROTO_UDP }, - { "ipv6", IPPROTO_IPV6 }, - { "gre", IPPROTO_GRE }, - { "esp", IPPROTO_ESP }, - { "ah", IPPROTO_AH }, - { "sctp", IPPROTO_SCTP }, - { "udplite", IPPROTO_UDPLITE }, - { "mpls", IPPROTO_MPLS }, - { "raw", IPPROTO_RAW }, - { "mptcp", IPPROTO_MPTCP }, + { "ip", IPPROTO_IP }, + { "icmp", IPPROTO_ICMP }, + { "igmp", IPPROTO_IGMP }, + { "tcp", IPPROTO_TCP }, + { "udp", IPPROTO_UDP }, + { "ipv6", IPPROTO_IPV6 }, + { "gre", IPPROTO_GRE }, + { "esp", IPPROTO_ESP }, + { "ah", IPPROTO_AH }, + { "sctp", IPPROTO_SCTP }, + { "udplite", IPPROTO_UDPLITE }, + { "mpls", IPPROTO_MPLS }, + { "raw", IPPROTO_RAW }, + { "mptcp", IPPROTO_MPTCP }, - { "nl_route", NETLINK_ROUTE }, + { "nl_route", NETLINK_ROUTE }, + { "nl_netfilter", NETLINK_NETFILTER }, { 0 }, }; @@ -261,7 +262,7 @@ static struct num send_flags[] = { static struct arg send_args[] = { { 0, { - "fd", INT, 0, + "fd", INT, FD, 0, 0, { 0 }, @@ -297,7 +298,7 @@ static struct arg send_args[] = { static struct arg sendto_args[] = { { 0, { - "fd", INT, 0, + "fd", INT, FD, 0, 0, { 0 }, @@ -346,7 +347,7 @@ static struct arg sendto_args[] = { { 0 } }; -static struct select sendmsg_name_select = { +static struct select msg_name_select = { &connect_family, { .d_num = connect_addr_select_family } }; @@ -355,13 +356,13 @@ static struct field sendmsg_msghdr[] = { "name", SELECT, 0, offsetof(struct msghdr, msg_name), sizeof(struct sockaddr_storage), - { .d_select = &sendmsg_name_select }, + { .d_select = &msg_name_select }, }, { "namelen", LONG, SIZE, offsetof(struct msghdr, msg_namelen), 0, - { .d_size = (intptr_t)&sendmsg_name_select }, + { .d_size = (intptr_t)&msg_name_select }, }, { "iov", STRING, WBUF | IOV, @@ -400,7 +401,7 @@ static struct field sendmsg_msghdr[] = { static struct arg sendmsg_args[] = { { 0, { - "fd", INT, 0, + "fd", INT, FD, 0, 0, { 0 }, @@ -425,6 +426,53 @@ static struct arg sendmsg_args[] = { { 0 } }; +static struct field recvmsg_msghdr[] = { + { + "name", SELECT, 0, + offsetof(struct msghdr, msg_name), + sizeof(struct sockaddr_storage), + { .d_select = &msg_name_select }, + }, + { + "namelen", LONG, SIZE, + offsetof(struct msghdr, msg_namelen), + 0, + { .d_size = (intptr_t)&msg_name_select }, + }, + { + "iov", STRING, RBUF | IOV, + offsetof(struct msghdr, msg_iov), + BUFSIZ, + { .d_iovlen = offsetof(struct msghdr, msg_iovlen) - + offsetof(struct msghdr, msg_iov) }, + }, + { + "iovlen", LONG, 0, + offsetof(struct msghdr, msg_iovlen), + 0, + { 0 }, + }, + { + "control", STRING, 0, + offsetof(struct msghdr, msg_control), + BUFSIZ, + { 0 }, + }, + { + "controllen", LONG, SIZE, + offsetof(struct msghdr, msg_controllen), + 0, + { 0 }, + }, + { + "flags", INT, 0, + offsetof(struct msghdr, msg_flags), + 0, + { 0 }, + }, + { 0 } +}; + static struct arg recvmsg_args[] = { { 0, { @@ -439,7 +487,7 @@ static struct arg recvmsg_args[] = { "msg", STRUCT, 0, 0, sizeof(struct msghdr), - { .d_struct = sendmsg_msghdr }, + { .d_struct = recvmsg_msghdr }, }, }, { 2, diff --git a/cooker/emit.c b/cooker/emit.c index 33355b6..7d13a02 100644 --- a/cooker/emit.c +++ b/cooker/emit.c @@ -217,18 +217,19 @@ void emit_store(struct gluten_ctx *g, struct gluten_offset dst, * @iov: Pointer to msg_iov, already stored in gluten * @iovlen: Pointer to msg_iovlen, already stored in gluten * @dst: gluten destination to copy dereferenced data + * @alloc: Allocation size (alloc - len bytes filled with zeroes) * @len: Maximum length of data to copy altogether */ struct gluten_offset emit_iovload(struct gluten_ctx *g, struct gluten_offset iov, struct gluten_offset iovlen, - size_t len) + size_t alloc, size_t len) { struct op *op = (struct op *)gluten_ptr(&g->g, g->ip); struct op_iovload *load = &op->op.iovload; struct gluten_offset dst; - dst = gluten_rw_alloc(g, len); + dst = gluten_rw_alloc(g, alloc); op->type = OP_IOVLOAD; @@ -237,6 +238,7 @@ struct gluten_offset emit_iovload(struct gluten_ctx *g, load->dst = dst; load->size = len; + load->zero_fill = alloc - len; debug(" %i: OP_IOVLOAD: #%i < (#%i) as iovec (size: %lu)", g->ip.offset, dst.offset, iov.offset, len); @@ -294,6 +296,7 @@ void emit_resolvefd(struct gluten_ctx *g, enum type type, * emit_bitwise(): Emit OP_BITWISE instruction: bitwise operation and store * @g: gluten context * @type: Type of operands + * @vec: Description of vector structure, NULL for scalar operation * @op_type: Type of bitwise operation * @dst: gluten pointer to destination operand, can be OFFSET_NULL * @x: gluten pointer to first source operand @@ -302,6 +305,7 @@ void emit_resolvefd(struct gluten_ctx *g, enum type type, * Return: offset to destination operand, allocated here if not given */ struct gluten_offset emit_bitwise(struct gluten_ctx *g, enum type type, + struct vec_desc *vec, enum bitwise_type op_type, struct gluten_offset dst, struct gluten_offset x, @@ -311,6 +315,7 @@ struct gluten_offset emit_bitwise(struct gluten_ctx *g, enum type type, struct op_bitwise *op_bitwise = &op->op.bitwise; struct gluten_offset o; struct bitwise_desc *desc; + char ip_str[BUFSIZ]; op->type = OP_BITWISE; @@ -319,21 +324,42 @@ struct gluten_offset emit_bitwise(struct gluten_ctx *g, enum type type, desc->size = gluten_size[type]; desc->type = op_type; - if (dst.type == OFFSET_NULL) - desc->dst = gluten_rw_alloc(g, desc->size); - else + + if (vec) + desc->vec = *vec; + + if (dst.type == OFFSET_NULL) { + size_t dst_size; + if (vec) /* FIXME: UIO_MAXIOV (1024) is a dubious choice */ + dst_size = (desc->size + sizeof(uint32_t)) * 1024; + else + dst_size = desc->size; + + desc->dst = gluten_rw_alloc(g, dst_size); + } else { desc->dst = dst; + } + desc->x = x; desc->y = y; op_bitwise->desc = o; - debug(" %i: OP_BITWISE: %s: #%lu (size: %lu) := %s: #%lu %s %s: #%lu", - g->ip.offset, + snprintf(ip_str, BUFSIZ, "%i", g->ip.offset); + + debug(" %s: OP_BITWISE: %s: #%lu (size: %lu) := %s: #%lu %s %s: #%lu", + ip_str, gluten_offset_name[desc->dst.type], desc->dst.offset, desc->size, gluten_offset_name[desc->x.type], desc->x.offset, bitwise_type_str[op_type], gluten_offset_name[desc->y.type], desc->y.offset); + if (vec) { + memset(ip_str, ' ', strlen(ip_str)); + debug(" %s vector start: %s: #%lu, length descriptor at %lu", + ip_str, + gluten_offset_name[vec->start.type], vec->start.offset, + vec->len_offset); + } if (++g->ip.offset > INST_MAX) die("Too many instructions"); @@ -345,12 +371,14 @@ struct gluten_offset emit_bitwise(struct gluten_ctx *g, enum type type, * emit_cmp(): Emit OP_CMP instruction: compare data from two offsets * @g: gluten context * @cmp_type: Type of comparison + * @vec: Description of vector structure, NULL for scalar comparison * @x: gluten pointer to first operand of comparison * @y: gluten pointer to second operand of comparison * @size: Size of comparison * @jmp: Jump direction if comparison is true */ void emit_cmp(struct gluten_ctx *g, enum op_cmp_type cmp_type, + struct vec_desc *vec, struct gluten_offset x, struct gluten_offset y, size_t size, enum jump_type jmp) { @@ -367,6 +395,11 @@ void emit_cmp(struct gluten_ctx *g, enum op_cmp_type cmp_type, desc->x = x; desc->y = y; desc->size = size; + if (vec) + desc->vec = *vec; + else + desc->vec.start.type = OFFSET_NULL; + desc->cmp = cmp_type; desc->jmp.type = OFFSET_INSTRUCTION; desc->jmp.offset = jmp; @@ -388,17 +421,18 @@ void emit_cmp(struct gluten_ctx *g, enum op_cmp_type cmp_type, * emit_cmp_field() - Emit OP_CMP for a given field type * @g: gluten context * @cmp: Type of comparison + * @vec: Description of vector structure, NULL for scalar comparison * @field: Description of field from system call model * @x: gluten pointer to first operand of comparison * @y: gluten pointer to second operand of comparison * @jmp: Jump direction if comparison is true */ void emit_cmp_field(struct gluten_ctx *g, enum op_cmp_type cmp, - struct field *field, + struct vec_desc *vec, struct field *field, struct gluten_offset x, struct gluten_offset y, enum jump_type jmp) { - emit_cmp(g, cmp, x, y, + emit_cmp(g, cmp, vec, x, y, field->size ? field->size : gluten_size[field->type], jmp); } diff --git a/cooker/emit.h b/cooker/emit.h index abdeda9..7948071 100644 --- a/cooker/emit.h +++ b/cooker/emit.h @@ -19,20 +19,21 @@ void emit_load(struct gluten_ctx *g, struct gluten_offset dst, struct gluten_offset emit_iovload(struct gluten_ctx *g, struct gluten_offset iov, struct gluten_offset iovlen, - size_t len); + size_t alloc, size_t len); void emit_store(struct gluten_ctx *g, struct gluten_offset dst, struct gluten_offset src, struct gluten_offset count); struct gluten_offset emit_seccomp_data(int index); struct gluten_offset emit_bitwise(struct gluten_ctx *g, enum type type, + struct vec_desc *desc, enum bitwise_type op_type, struct gluten_offset dst, struct gluten_offset x, struct gluten_offset y); -void emit_cmp(struct gluten_ctx *g, enum op_cmp_type cmp, +void emit_cmp(struct gluten_ctx *g, enum op_cmp_type cmp, struct vec_desc *vec, struct gluten_offset x, struct gluten_offset y, size_t size, enum jump_type jmp); void emit_cmp_field(struct gluten_ctx *g, enum op_cmp_type cmp, - struct field *field, + struct vec_desc *vec, struct field *field, struct gluten_offset base, struct gluten_offset match, enum jump_type jmp); void emit_return(struct gluten_ctx *g, struct gluten_offset v, diff --git a/cooker/match.c b/cooker/match.c index 1fd726f..f65ac5c 100644 --- a/cooker/match.c +++ b/cooker/match.c @@ -22,9 +22,70 @@ #include <linux/netlink.h> #include <linux/rtnetlink.h> +#include <linux/netfilter/nfnetlink.h> +#include <linux/netfilter/nf_tables.h> +#include <linux/netfilter/nf_tables_compat.h> static struct num netlink_types[] = { - { "newroute", RTM_NEWROUTE }, + { "newroute", RTM_NEWROUTE }, + +#define SUBSYS_NFCOMPAT(x) (NFNL_SUBSYS_NFT_COMPAT << 8 | (x)) + { "nf_compat_get", (SUBSYS_NFCOMPAT(NFNL_MSG_COMPAT_GET))}, + +#define SUBSYS_NFT(x) (NFNL_SUBSYS_NFTABLES << 8 | (x)) + { "nf_get_any", + SUBSYS_NFT(NFT_MSG_GETTABLE | NFT_MSG_GETCHAIN | NFT_MSG_GETRULE | + NFT_MSG_GETSET | NFT_MSG_GETSETELEM | NFT_MSG_GETGEN | + NFT_MSG_GETFLOWTABLE | NFT_MSG_GETOBJ) | + SUBSYS_NFCOMPAT(NFNL_MSG_COMPAT_GET) }, + +#undef SUBSYS_NFCOMPAT + + { "nf_newtable", SUBSYS_NFT(NFT_MSG_NEWTABLE) }, + { "nf_gettable", SUBSYS_NFT(NFT_MSG_GETTABLE) }, + { "nf_deltable", SUBSYS_NFT(NFT_MSG_DELTABLE) }, + { "nf_destroytable", SUBSYS_NFT(NFT_MSG_DESTROYTABLE) }, + /* ignores ENOENT */ + + { "nf_newchain", SUBSYS_NFT(NFT_MSG_NEWCHAIN) }, + { "nf_getchain", SUBSYS_NFT(NFT_MSG_GETCHAIN) }, + { "nf_delchain", SUBSYS_NFT(NFT_MSG_DELCHAIN) }, + { "nf_destroychain", SUBSYS_NFT(NFT_MSG_DESTROYCHAIN) }, + + { "nf_newrule", SUBSYS_NFT(NFT_MSG_NEWRULE) }, + { "nf_getrule", SUBSYS_NFT(NFT_MSG_GETRULE) }, + { "nf_getrule_reset", SUBSYS_NFT(NFT_MSG_GETRULE_RESET) }, + { "nf_delrule", SUBSYS_NFT(NFT_MSG_DELRULE) }, + { "nf_destroyrule", SUBSYS_NFT(NFT_MSG_DESTROYRULE) }, + + { "nf_newset", SUBSYS_NFT(NFT_MSG_NEWSET) }, + { "nf_getset", SUBSYS_NFT(NFT_MSG_GETSET) }, + { "nf_delset", SUBSYS_NFT(NFT_MSG_DELSET) }, + { "nf_destroyset", SUBSYS_NFT(NFT_MSG_DESTROYSET) }, + + { "nf_newsetelem", SUBSYS_NFT(NFT_MSG_NEWSETELEM) }, + { "nf_getsetelem", SUBSYS_NFT(NFT_MSG_GETSETELEM) }, + { "nf_getsetelem_reset", SUBSYS_NFT(NFT_MSG_GETSETELEM_RESET) }, + { "nf_delsetelem", SUBSYS_NFT(NFT_MSG_DELSETELEM) }, + { "nf_destroysetelem", SUBSYS_NFT(NFT_MSG_DESTROYSETELEM) }, + + { "nf_newgen", SUBSYS_NFT(NFT_MSG_NEWGEN) }, + { "nf_getgen", SUBSYS_NFT(NFT_MSG_GETGEN) }, + + { "nf_trace", SUBSYS_NFT(NFT_MSG_TRACE) }, + + { "nf_newobj", SUBSYS_NFT(NFT_MSG_NEWOBJ) }, + { "nf_getobj", SUBSYS_NFT(NFT_MSG_GETOBJ) }, + { "nf_getobj_reset", SUBSYS_NFT(NFT_MSG_GETOBJ_RESET) }, + { "nf_delobj", SUBSYS_NFT(NFT_MSG_DELOBJ) }, + { "nf_destroyobj", SUBSYS_NFT(NFT_MSG_DESTROYOBJ) }, + + { "nf_newflowtable", SUBSYS_NFT(NFT_MSG_NEWFLOWTABLE) }, + { "nf_getflowtable", SUBSYS_NFT(NFT_MSG_GETFLOWTABLE) }, + { "nf_delflowtable", SUBSYS_NFT(NFT_MSG_DELFLOWTABLE) }, + { "nf_destroyflowtable", SUBSYS_NFT(NFT_MSG_DESTROYFLOWTABLE) }, +#undef SUBSYS_NFT + { 0 }, }; @@ -109,6 +170,7 @@ static struct gluten_offset arg_load(struct gluten_ctx *g, struct arg *a) */ static union value parse_field(struct gluten_ctx *g, struct gluten_offset offset, + struct vec_desc *vec, enum op_cmp_type cmp, enum jump_type jump, int index, struct field *f, JSON_Value *jvalue) { @@ -134,7 +196,7 @@ ______________________ _____________ */ v.v_num = ((long long)0xfff << 44) | (0xfff << 8); mask_offset = emit_data(g, U64, 0, &v); - offset = emit_bitwise(g, U64, BITWISE_AND, NULL_OFFSET, + offset = emit_bitwise(g, U64, NULL, BITWISE_AND, NULL_OFFSET, offset, mask_offset); break; case GNU_DEV_MINOR: @@ -144,7 +206,7 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx */ v.v_num = 0xff | ((long long)0xfff << 20); mask_offset = emit_data(g, U64, 0, &v); - offset = emit_bitwise(g, U64, BITWISE_AND, NULL_OFFSET, + offset = emit_bitwise(g, U64, NULL, BITWISE_AND, NULL_OFFSET, offset, mask_offset); break; default: @@ -155,9 +217,19 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx if (f->flags & IOV) { struct gluten_offset iovlen = offset; + size_t alloc; + + /* vectorised ops need a zero length descriptor at the end */ + if (json_value_get_type(jvalue) == JSONObject && + (tmp = json_value_get_object(jvalue)) && + json_object_get_value(tmp, "netlink")) + alloc = f->size + + sizeof(((struct nlmsghdr *)NULL)->nlmsg_len); + else + alloc = f->size; iovlen.offset += f->desc.d_iovlen; - offset = emit_iovload(g, offset, iovlen, f->size); + offset = emit_iovload(g, offset, iovlen, alloc, f->size); } if (json_value_get_type(jvalue) == JSONObject && @@ -188,7 +260,16 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx } jvalue = json_array_get_value(set, i); - parse_field(g, offset, cmp, jump, index, f, jvalue); + + /* FIXME: ugly. Otherwise nested parse_field() will + * increment twice. + */ + offset.offset -= f->offset; + + parse_field(g, offset, vec, cmp, jump, index, f, + jvalue); + + offset.offset += f->offset; } return v; /* No SELECT based on sets... of course */ @@ -215,12 +296,12 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx &set, &cmp, &cmpterm); set_offset = emit_data(g, f->type, 0, &set); - masked = emit_bitwise(g, f->type, BITWISE_AND, + masked = emit_bitwise(g, f->type, vec, BITWISE_AND, NULL_OFFSET, offset, set_offset); cmp_offset = emit_data(g, f->type, 0, &cmpterm); - emit_cmp(g, cmp, masked, cmp_offset, + emit_cmp(g, cmp, vec, masked, cmp_offset, gluten_size[f->type], jump); emit_bpf_arg(index, f->type, cmpterm, set, cmp, g->mode); @@ -241,9 +322,13 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx } else if (f->flags & MASK) { mask.v_num = value_get_mask(f->desc.d_num); mask_offset = emit_data(g, f->type, 0, &mask); - data_offset = emit_bitwise(g, f->type, BITWISE_AND, + + data_offset = emit_bitwise(g, f->type, vec, BITWISE_AND, NULL_OFFSET, offset, mask_offset); + if (vec) + vec->len_offset = 0; + v.v_num = value_get_num(f->desc.d_num, jvalue); } else { v.v_num = value_get_num(f->desc.d_num, jvalue); @@ -251,7 +336,7 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx const_offset = emit_data(g, f->type, 0, &v); - emit_cmp(g, cmp, data_offset, const_offset, + emit_cmp(g, cmp, vec, data_offset, const_offset, gluten_size[f->type], jump); emit_bpf_arg(index, f->type, v, mask, cmp, g->mode); @@ -266,7 +351,7 @@ ______________________ _____________ v.v_num = (v.v_num & 0xfff) << 8 | (v.v_num & ~0xfff) << 32; const_offset = emit_data(g, U64, 0, &v); - emit_cmp_field(g, cmp, f, offset, const_offset, jump); + emit_cmp_field(g, cmp, vec, f, offset, const_offset, jump); filter_needs_deref(); /* No shifts in BPF */ break; @@ -278,7 +363,7 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx v.v_num = value_get_num(f->desc.d_num, jvalue); v.v_num = (v.v_num & 0xff) | (v.v_num & ~0xfff) << 12; const_offset = emit_data(g, U64, 0, &v); - emit_cmp_field(g, cmp, f, offset, const_offset, jump); + emit_cmp_field(g, cmp, vec, f, offset, const_offset, jump); filter_needs_deref(); /* No shifts in BPF */ break; @@ -292,17 +377,43 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx sel = jvalue; } - v = parse_field(g, offset, cmp, jump, index, f_inner, sel); + v = parse_field(g, offset, vec, cmp, jump, index, f_inner, sel); f = select_field(g, index, f->desc.d_select, v); - if (f) - parse_field(g, offset, cmp, jump, index, f, jvalue); + if (f) { + parse_field(g, offset, vec, cmp, jump, index, f, + jvalue); + } break; case STRING: if (json_value_get_type(jvalue) == JSONObject && (tmp = json_value_get_object(jvalue))) { if ((jvalue = json_object_get_value(tmp, "netlink"))) { - parse_field(g, offset, cmp, jump, index, + struct vec_desc v_nl, *vecptr; + + /* FIXME: even send()/sendto() might need + * vectorised operations + */ + if (f->flags & IOV) { + v_nl.start = offset; + v_nl.len_offset = offsetof(struct nlmsghdr, + nlmsg_len); + vecptr = &v_nl; + } else { + vecptr = NULL; + } + + /* TODO: mark as CMPVEC, with: + * - offset of length (offsetof nlmsghdr) + * - vector pointer: that's already offset? + * - offset of comparison in vector (0 atm) + * - second term of comparison (from jvalue) + * - length (still needed?) + * + * plus BITWISEVEC? is it even needed? + */ + + parse_field(g, offset, vecptr, cmp, jump, index, &netlink_header, jvalue); } else { die(" unrecognised blob type"); @@ -317,8 +428,8 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx die(" string %s too long for field", v.v_str); const_offset = emit_data(g, STRING, strlen(v.v_str) + 1, &v); - emit_cmp(g, CMP_NE, offset, const_offset, strlen(v.v_str) + 1, - JUMP_NEXT_BLOCK); + emit_cmp(g, CMP_NE, vec, offset, const_offset, + strlen(v.v_str) + 1, JUMP_NEXT_BLOCK); break; case FDPATH: case FDMOUNT: @@ -328,8 +439,8 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx const_offset = emit_data(g, STRING, size, &v); seccomp_offset = emit_seccomp_data(index); emit_resolvefd(g, f->type, seccomp_offset, offset, size); - emit_cmp(g, CMP_NE, offset, const_offset, size, - JUMP_NEXT_BLOCK); + emit_cmp(g, CMP_NE, vec, offset, const_offset, + size, JUMP_NEXT_BLOCK); break; case STRUCT: for (f_inner = f->desc.d_struct; f_inner->name; f_inner++) { @@ -340,7 +451,7 @@ xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx if (!field_value) continue; - parse_field(g, offset, cmp, jump, index, f_inner, + parse_field(g, offset, vec, cmp, jump, index, f_inner, field_value); } break; @@ -365,7 +476,8 @@ static void parse_arg(struct gluten_ctx *g, JSON_Value *jvalue, struct arg *a) offset = arg_load(g, a); - parse_field(g, offset, CMP_NE, JUMP_NEXT_BLOCK, a->pos, &a->f, jvalue); + parse_field(g, offset, NULL, CMP_NE, JUMP_NEXT_BLOCK, a->pos, &a->f, + jvalue); } /** @@ -407,16 +519,25 @@ static void parse_match(struct gluten_ctx *g, JSON_Object *obj, void handle_matches(struct gluten_ctx *g, JSON_Value *value) { JSON_Array *matches = json_value_get_array(value); - unsigned i; + unsigned i, count; - for (i = 0; i < json_array_get_count(matches); i++) { + if (matches) + count = json_array_get_count(matches); + else + count = 1; + + for (i = 0; i < count; i++) { JSON_Object *match, *args; struct call **set, *call; const char *name; + if (matches) + match = json_array_get_object(matches, i); + else + match = json_value_get_object(value); + g->mr = g->ip; - match = json_array_get_object(matches, i); name = json_object_get_name(match, 0); args = json_object_get_object(match, name); debug(" Parsing match %i: %s", i, name); diff --git a/demo/iptables.hjson b/demo/iptables.hjson new file mode 100644 index 0000000..d24f476 --- /dev/null +++ b/demo/iptables.hjson @@ -0,0 +1,214 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +/* seitan - Syscall Expressive Interpreter, Transformer and Notifier + * + * demo/iptables.hjson - Example for iptables-nft: fetch ruleset, add rules + * + * Copyright (c) 2024 Red Hat GmbH + * Author: Stefano Brivio <sbrivio@redhat.com> + * + * Example of stand-alone usage: + * + * ./seitan-cooker \ + * -i demo/iptables.hjson -g demo/iptables.gluten -f demo/iptables.bpf + * ./seitan-eater \ + * -i demo/iptables.bpf -- /sbin/iptables -t mangle -A FORWARD -j LOG + * # blocks + * + * ./seitan -p $(pgrep seitan-eater) -i demo/iptables.gluten + * # as root or with CAP_NET_ADMIN: adds rule on behalf of caller + * + * ./seitan-eater \ + * -i demo/iptables.bpf -- /sbin/iptables -t mangle -D FORWARD -j LOG + * # blocks + * + * ./seitan -p $(pgrep seitan-eater) -i demo/iptables.gluten + * # as root or with CAP_NET_ADMIN: deletes rule on behalf of caller + */ + +[ + /* When the target process tries to open a netlink socket for netfilter, open + * one on behalf of the caller, owned by us, and replace it in the caller. + * + * For netlink operations, there's always a double permission check: + * both opener of the socket and sender of the messages need to have matching + * capabilities, see netlink_ns_capable() in net/netlink/af_netlink.c. + * + * This block takes care of the first part. + */ + { + "match": { + "socket": { + "family" : "netlink", + "type" : "raw", + "protocol" : "nl_netfilter" + } + /* socket(2) doesn't point to memory, so we can safely let any unrelated + * system calls proceed, directly in the caller, without replaying it + * ourselves. + */ + }, + "call": { + "socket": { + "family" : "netlink", + "type" : "raw", + "flags" : 0, + "protocol" : "nl_netfilter" + }, + "ret": "fd" + }, + "fd": { + "src": { "get": "fd" }, + "close_on_exec": true, + "return": true + } + }, + + /* Second part: send messages on behalf of the target process. + * + * First, the ones iptables needs to check for nftables compatibility, and to + * fetch tables, chains, rules and sets, including their generation (version) + * identifier. + * + * These are simple messages, without batches, using sendto(). + */ + { + "match": { + "sendto": { + "fd": { + "set": "fd" + }, + "buf": { + "set": "buf", + "value": { + "netlink": { + "type": { + "in": [ + "nf_compat_get", + "nf_getgen", + "nf_gettable", + "nf_getchain", + "nf_getrule", + "nf_getset" + ] + } + } + } + }, + "len" : { "set": "len" }, + "addr": { "set": "addr" } + } + }, + "call": { + "sendto": { + "fd": { "get": "fd" }, + "buf": { "get": "buf" }, + "len": { "get": "len" }, + "addr": { "get": "addr" }, + "flags": 0 + }, + "ret": "rc" + }, + "return": { "value": "rc", "error": "rc" } + }, + + /* sendto(2) points to memory, so we need to match on any unrelated sendto() + * call and replay it ourselves, but pretending we're the original process + * (see "context" below). Otherwise, a thread of the target process can fool + * us into sending other messages with our capability set. + */ + { + "match": { + "sendto": { + "fd": { "set": "fd" }, + "buf": { "set": "buf" }, + "len": { "set": "len" }, + "addr": { "set": "addr" }, + "flags": { "set": "flags" } + } + }, + "call": { + "sendto": { + "fd": { "get": "fd" }, + "buf": { "get": "buf" }, + "len": { "get": "len" }, + "addr": { "get": "addr" }, + "flags": { "get": "flags" } + }, + "context": { "uid": "caller", "gid": "caller" } + } + }, + + /* Now deal with the actual rule insertion or deletion: those are batched + * messages, using sendmsg(). Replay the message and relay return code and any + * error back. + */ + { + "match": { + "sendmsg": { + "fd": { "set": "fd" }, + "msg": { + "iov": { + "set": "buf", + "value": { + "netlink": { + "type": { "in": [ "nf_newrule", "nf_delrule" ] } + } + } + } + } + } + }, + "call": { + "sendmsg": { + "fd": { "get": "fd" }, + "msg": { + "name": { + "family": "netlink", + "pid": 0, + "groups": 0 + }, + "iovlen": 1, + "iov": { "get": "buf" } + }, + "flags": 0 + }, + "ret": "rc" + }, + "return": { "value": "rc", "error": "rc" } + }, + + /* Same as sendto(2): sendmsg(2) points to memory. Replay any unrelated system + * call with the credentials from the target process. + */ + { + "match": { + "sendmsg": { + "fd": { "set": "fd" }, + "msg": { + "name": { "set": "name" }, + "namelen": { "set": "namelen" }, + "iov": { "set": "buf" }, + "control": { "set": "control" }, + "controllen": { "set": "controllen" } + }, + "flags": { "set": "flags" } + } + }, + "call": { + "sendmsg": { + "fd": { "get": "fd" }, + "msg": { + "name": { "get": "name" }, + "namelen": { "get": "namelen" }, + "iov": { "get": "buf" }, + "iovlen": 1, + "control": { "get": "control" }, + "controllen": { "get": "controllen" } + }, + "flags": { "get": "flags" } + }, + "context": { "uid": "caller", "gid": "caller" } + } + } +] diff --git a/demo/nft.hjson b/demo/nft.hjson new file mode 100644 index 0000000..4ad7f1d --- /dev/null +++ b/demo/nft.hjson @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +/* seitan - Syscall Expressive Interpreter, Transformer and Notifier + * + * demo/nft.hjson - Example for nft(8): fetch ruleset, add/delete set elements + * + * Copyright (c) 2024 Red Hat GmbH + * Author: Stefano Brivio <sbrivio@redhat.com> + * + * Example of stand-alone usage. Prepare a table and a set for testing, first: + * + * nft add table ip test_t + * nft add set ip test_t test_s '{ type ipv4_addr ; }' + * + * Now add the set element: + * + * ./seitan-cooker \ + * -i demo/nft.hjson -g demo/nft.gluten -f demo/nft.bpf + * ./seitan-eater \ + * -i demo/nft.bpf -- /sbin/nft add element ip test_t test_s { 1.2.3.4 } + * # blocks + * + * ./seitan -p $(pgrep seitan-eater) -i demo/nft.gluten + * # as root or with CAP_NET_ADMIN: add element on behalf of caller + * + * nft list ruleset # Check that the new element is there + * + * ./seitan-eater \ + * -i demo/nft.bpf -- /sbin/nft delete element ip test_t test_s { 1.2.3.4 } + * # blocks + * + * ./seitan -p $(pgrep seitan-eater) -i demo/nft.gluten + * # as root or with CAP_NET_ADMIN: deletes element on behalf of caller + * + */ + +[ + /* Open netlink socket on behalf of the caller, owned by us, and replace in + * the caller. + * + * For netlink operations, there's always a double permission check: + * both opener of the socket and sender of the messages need to have matching + * capabilities, see netlink_ns_capable() in net/netlink/af_netlink.c. + * + * This block takes care of the first part. + */ + { + "match": { + "socket": { + "family" : "netlink", + "type" : "raw", + "protocol" : "nl_netfilter" + } + /* socket(2) doesn't point to memory, so we can safely let any unrelated + * system calls proceed, directly in the caller, without replaying it + * ourselves. + */ + }, + "call": { + "socket": { + "family" : "netlink", + "type" : "raw", + "flags" : 0, + "protocol" : "nl_netfilter" + }, + "ret": "fd" + }, + "fd": { + "src": { "get": "fd" }, + "close_on_exec": true, + "return": true + } + }, + + /* Second part: send messages on behalf of the target process. + * + * First, the ones to fetch tables, chains, sets, flow tables, and objects, + * including their generation (version) identifier. + * + * These are simple messages, without batches, using sendto(). + */ + { + "match": { + "sendto": { + "fd": { + "set": "fd" + }, + "buf": { + "set": "buf", + "value": { + "netlink": { + "type": { + "in": [ + "nf_getgen", + "nf_gettable", + "nf_getchain", + "nf_getobj", + "nf_getflowtable", + "nf_getset" + ] + } + } + } + }, + "len" : { "set": "len" }, + "addr": { "set": "addr" } + } + }, + "call": { + "sendto": { + "fd": { "get": "fd" }, + "buf": { "get": "buf" }, + "len": { "get": "len" }, + "addr": { "get": "addr" }, + "flags": 0 + }, + "ret": "rc" + }, + "return": { "value": "rc", "error": "rc" } + }, + + /* sendto(2) points to memory, so we need to match on any unrelated sendto() + * call and replay it ourselves, but pretending we're the original process + * (see "context" below). Otherwise, a thread of the target process can fool + * us into sending other messages with our capability set. + */ + { + "match": { + "sendto": { + "fd": { "set": "fd" }, + "buf": { "set": "buf" }, + "len": { "set": "len" }, + "addr": { "set": "addr" }, + "flags": { "set": "flags" } + } + }, + "call": { + "sendto": { + "fd": { "get": "fd" }, + "buf": { "get": "buf" }, + "len": { "get": "len" }, + "addr": { "get": "addr" }, + "flags": { "get": "flags" } + }, + "context": { "uid": "caller", "gid": "caller" } + } + }, + + /* Now deal with the actual element insertion or deletion: those are batched + * messages, using sendmsg(). Replay the message and relay return code and any + * error back. + */ + { + "match": { + "sendmsg": { + "fd": { "set": "fd" }, + "msg": { + "iov": { + "set": "buf", + "value": { + "netlink": { + "type": { "in": [ "nf_newsetelem", "nf_delsetelem" ] } + } + } + } + } + } + }, + "call": { + "sendmsg": { + "fd": { "get": "fd" }, + "msg": { + "name": { + "family": "netlink", + "pid": 0, + "groups": 0 + }, + "iovlen": 1, + "iov": { "get": "buf" } + }, + "flags": 0 + }, + "ret": "rc" + }, + "return": { "value": "rc", "error": "rc" } + }, + + /* Same as sendto(2): sendmsg(2) points to memory. Replay any unrelated system + * call with the credentials from the target process. + */ + { + "match": { + "sendmsg": { + "fd": { "set": "fd" }, + "msg": { + "name": { "set": "name" }, + "namelen": { "set": "namelen" }, + "iov": { "set": "buf" }, + "control": { "set": "control" }, + "controllen": { "set": "controllen" } + }, + "flags": { "set": "flags" } + } + }, + "call": { + "sendmsg": { + "fd": { "get": "fd" }, + "msg": { + "name": { "get": "name" }, + "namelen": { "get": "namelen" }, + "iov": { "get": "buf" }, + "iovlen": 1, + "control": { "get": "control" }, + "controllen": { "get": "controllen" } + }, + "flags": { "get": "flags" } + }, + "context": { "uid": "caller", "gid": "caller" } + } + } +] diff --git a/operations.c b/operations.c index eb8d614..4438879 100644 --- a/operations.c +++ b/operations.c @@ -459,6 +459,8 @@ int op_iovload(const struct seccomp_notif *req, int notifier, struct gluten *g, close(fd); + memset(dst + count, 0, load->size - count + load->zero_fill); + return 0; } @@ -592,8 +594,11 @@ int op_bitwise(const struct seccomp_notif *req, int notifier, struct gluten *g, struct op_bitwise *op) { const struct bitwise_desc *desc = gluten_ptr(&req->data, g, op->desc); - const unsigned char *x, *y; - unsigned char *dst; + const struct vec_desc vec = desc->vec; + const unsigned char *x_ptr, *y_ptr; + struct gluten_offset x, dst; + unsigned char *dst_ptr; + uint32_t *vlen; unsigned i; (void)notifier; @@ -601,10 +606,6 @@ int op_bitwise(const struct seccomp_notif *req, int notifier, struct gluten *g, if (!desc) return -1; - dst = gluten_write_ptr( g, desc->dst); - x = gluten_ptr(&req->data, g, desc->x); - y = gluten_ptr(&req->data, g, desc->y); - /* if (!dst || !src || !mask || !check_gluten_limits(desc->dst, desc->size) || @@ -612,6 +613,7 @@ int op_bitwise(const struct seccomp_notif *req, int notifier, struct gluten *g, !check_gluten_limits(desc->mask, desc->size)) return -1; */ + debug(" op_bitwise: dst=(%s %d) := x=(%s %d) %s y=(%s %d) size=%d", gluten_offset_name[desc->dst.type], desc->dst.offset, gluten_offset_name[desc->x.type], desc->x.offset, @@ -619,13 +621,37 @@ int op_bitwise(const struct seccomp_notif *req, int notifier, struct gluten *g, gluten_offset_name[desc->y.type], desc->y.offset, desc->size); - for (i = 0; i < desc->size; i++) { - if (desc->type == BITWISE_AND) - dst[i] = x[i] & y[i]; - else if (desc->type == BITWISE_OR) - dst[i] = x[i] | y[i]; - else - return -1; + if (vec.start.type != OFFSET_NULL) { + debug(" vector start=(%s %d), length offset: %i", + gluten_offset_name[vec.start.type], vec.start.offset, + vec.len_offset); + } + + if (vec.start.type == OFFSET_NULL) + vlen = &((uint32_t){ 1 }); + else + vlen = (uint32_t *)gluten_ptr(&req->data, g, vec.start); + + y_ptr = gluten_ptr(&req->data, g, desc->y); + + for (x = desc->x, dst = desc->dst; + *vlen; + x.offset += *vlen, vlen += *vlen, dst.offset += desc->size) { + + x_ptr = gluten_ptr(&req->data, g, x); + dst_ptr = gluten_write_ptr( g, dst); + + for (i = 0; i < desc->size; i++) { + if (desc->type == BITWISE_AND) + dst_ptr[i] = x_ptr[i] & y_ptr[i]; + else if (desc->type == BITWISE_OR) + dst_ptr[i] = x_ptr[i] | y_ptr[i]; + else + return -1; + } + + if (vec.start.type == OFFSET_NULL) + break; } return 0; @@ -683,9 +709,13 @@ int op_cmp(const struct seccomp_notif *req, int notifier, struct gluten *g, struct op_cmp *op) { const struct cmp_desc *desc = gluten_ptr(&req->data, g, op->desc); + bool some = false, all = true, verdict; + const struct vec_desc vec = desc->vec; char str_x[PATH_MAX], str_y[PATH_MAX]; + const void *x_ptr, *y_ptr; + struct gluten_offset x; enum op_cmp_type cmp; - const void *px, *py; + uint32_t *vlen; int res; (void)notifier; @@ -693,29 +723,88 @@ int op_cmp(const struct seccomp_notif *req, int notifier, struct gluten *g, if (!desc) return -1; - px = gluten_ptr(&req->data, g, desc->x); - py = gluten_ptr(&req->data, g, desc->y); - cmp = desc->cmp; - - if (!px || !py || - !check_gluten_limits(desc->x, desc->size) || - !check_gluten_limits(desc->y, desc->size)) - return -1; str_offset_value(req, g, &desc->x, desc->size, str_x, PATH_MAX); str_offset_value(req, g, &desc->y, desc->size, str_y, PATH_MAX); debug(" op_cmp: operands x=%s y=%s", str_x, str_y); - res = memcmp(px, py, desc->size); + if (vec.start.type != OFFSET_NULL) { + debug(" vector start=(%s %d), length offset: %i", + gluten_offset_name[vec.start.type], vec.start.offset, + vec.len_offset); + } + + if (vec.start.type == OFFSET_NULL) + vlen = &((uint32_t){ 1 }); + else + vlen = (uint32_t *)gluten_ptr(&req->data, g, vec.start); + + y_ptr = gluten_ptr(&req->data, g, desc->y); - if ((res == 0 && (cmp == CMP_EQ || cmp == CMP_LE || cmp == CMP_GE)) || - (res < 0 && (cmp == CMP_LT || cmp == CMP_LE)) || - (res > 0 && (cmp == CMP_GT || cmp == CMP_GE)) || - (res != 0 && (cmp == CMP_NE))) { - debug(" op_cmp: successful comparison, jump to %d", - desc->jmp.offset); + if (!y_ptr || !check_gluten_limits(desc->y, desc->size)) + return -1; + + cmp = desc->cmp; + + for (x = desc->x; + *vlen; + x.offset += *vlen, vlen = (uint32_t *)((uint8_t *)vlen + *vlen)) { + unsigned char *c; + int __i; + + debug(" in loop, vlen: %u", *vlen); + + x_ptr = gluten_ptr(&req->data, g, x); + + if (!x_ptr || !check_gluten_limits(x, desc->size)) + return -1; + + debug(" in loop #2"); + + res = memcmp(x_ptr, y_ptr, desc->size); + + debug("=== x: %04x, y: %04x", *(uint16_t *)x_ptr, *(uint16_t *)y_ptr); + + c = (unsigned char *)x_ptr; + for (__i = 0; __i < 32; __i += 4) + debug("%02x %02x %02x %02x", c[__i], c[__i + 1], c[__i + 2], c[__i + 3]); + + if ((res == 0 && + (cmp == CMP_EQ || cmp == CMP_LE || cmp == CMP_GE)) || + (res < 0 && + (cmp == CMP_LT || cmp == CMP_LE)) || + (res > 0 && + (cmp == CMP_GT || cmp == CMP_GE)) || + (res != 0 && + (cmp == CMP_NE))) + some = true; + else + all = false; + + if (vec.start.type == OFFSET_NULL) + break; + + debug(" in loop #3"); + } + + /* FIXME: vectors always imply the existential quantifier for now: + * CMP_NE and all non-equal: jump + * CMP_EQ and some equal: jump + */ + if (vec.start.type == OFFSET_NULL) + verdict = some; + else if (cmp == CMP_NE) + verdict = all; + else + verdict = some; + + debug(" op_cmp: comparison: %s for some, %s for all, verdict: %s", + some ? "true" : "false", all ? "true" : "false", + verdict ? "true" : "false"); + + if (verdict) { + debug(" -> jump to %d", desc->jmp.offset); return desc->jmp.offset; } - debug(" op_cmp: comparison is false"); return 0; } |