From bd28075ee0bf121ef4fe50e34146efe14acee07b Mon Sep 17 00:00:00 2001 From: Arturo Borrero Date: Tue, 29 Oct 2013 23:44:25 +0100 Subject: src: add fprintf API functions Now it's possible to print directly from libnftables to a file or other stream. The caller must explicitly print the trailing '\n' in this call. The error reporting of fprintf (< 0) is respected. However, we have already print some information in case that the default (plain text) output is used, that output is mostly intended for debugging so it should not be a problem. Signed-off-by: Arturo Borrero Gonzalez Signed-off-by: Pablo Neira Ayuso --- include/libnftables/chain.h | 2 + include/libnftables/rule.h | 2 + include/libnftables/ruleset.h | 3 + include/libnftables/set.h | 3 + include/libnftables/table.h | 2 + src/chain.c | 13 +++ src/internal.h | 4 + src/libnftables.map | 6 ++ src/rule.c | 13 +++ src/ruleset.c | 203 ++++++++++++++++++++++++++++++++++++++++++ src/set.c | 13 +++ src/set_elem.c | 13 +++ src/table.c | 13 +++ src/utils.c | 27 ++++++ 14 files changed, 317 insertions(+) diff --git a/include/libnftables/chain.h b/include/libnftables/chain.h index d85a2a2..66f19c0 100644 --- a/include/libnftables/chain.h +++ b/include/libnftables/chain.h @@ -1,6 +1,7 @@ #ifndef _CHAIN_H_ #define _CHAIN_H_ +#include #include #include @@ -60,6 +61,7 @@ enum nft_chain_parse_type { int nft_chain_parse(struct nft_chain *c, enum nft_chain_parse_type type, const char *data); int nft_chain_snprintf(char *buf, size_t size, struct nft_chain *t, uint32_t type, uint32_t flags); +int nft_chain_fprintf(FILE *fp, struct nft_chain *c, uint32_t type, uint32_t flags); struct nlmsghdr *nft_chain_nlmsg_build_hdr(char *buf, uint16_t cmd, uint16_t family, uint16_t type, uint32_t seq); int nft_chain_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_chain *t); diff --git a/include/libnftables/rule.h b/include/libnftables/rule.h index a501d2d..cdbd8d2 100644 --- a/include/libnftables/rule.h +++ b/include/libnftables/rule.h @@ -1,6 +1,7 @@ #ifndef _RULE_H_ #define _RULE_H_ +#include #include #include @@ -58,6 +59,7 @@ enum nft_rule_parse_type { int nft_rule_parse(struct nft_rule *r, enum nft_rule_parse_type type, const char *data); int nft_rule_snprintf(char *buf, size_t size, struct nft_rule *t, uint32_t type, uint32_t flags); +int nft_rule_fprintf(FILE *fp, struct nft_rule *r, uint32_t type, uint32_t flags); struct nlmsghdr *nft_rule_nlmsg_build_hdr(char *buf, uint16_t cmd, uint16_t family, uint16_t type, uint32_t seq); int nft_rule_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_rule *t); diff --git a/include/libnftables/ruleset.h b/include/libnftables/ruleset.h index a4a1279..35e4d71 100644 --- a/include/libnftables/ruleset.h +++ b/include/libnftables/ruleset.h @@ -1,6 +1,8 @@ #ifndef _RULESET_H_ #define _RULESET_H_ +#include + #ifdef __cplusplus extern "C" { #endif @@ -37,6 +39,7 @@ enum nft_ruleset_parse_type { int nft_ruleset_parse(struct nft_ruleset *rs, enum nft_ruleset_parse_type type, const char *data); int nft_ruleset_snprintf(char *buf, size_t size, const struct nft_ruleset *rs, uint32_t type, uint32_t flags); +int nft_ruleset_fprintf(FILE *fp, const struct nft_ruleset *rs, uint32_t type, uint32_t flags); #ifdef __cplusplus } /* extern "C" */ diff --git a/include/libnftables/set.h b/include/libnftables/set.h index 14a6327..a087009 100644 --- a/include/libnftables/set.h +++ b/include/libnftables/set.h @@ -1,6 +1,7 @@ #ifndef _NFT_SET_H_ #define _NFT_SET_H_ +#include #include #include @@ -38,6 +39,7 @@ int nft_set_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_set *s); int nft_set_elems_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_set *s); int nft_set_snprintf(char *buf, size_t size, struct nft_set *s, uint32_t type, uint32_t flags); +int nft_set_fprintf(FILE *fp, struct nft_set *s, uint32_t type, uint32_t flags); struct nft_set_list; @@ -108,6 +110,7 @@ int nft_set_elem_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_set_elem *s) int nft_set_elem_parse(struct nft_set_elem *e, enum nft_set_parse_type type, const char *data); int nft_set_elem_snprintf(char *buf, size_t size, struct nft_set_elem *s, uint32_t type, uint32_t flags); +int nft_set_elem_fprintf(FILE *fp, struct nft_set_elem *se, uint32_t type, uint32_t flags); int nft_set_elem_foreach(struct nft_set *s, int (*cb)(struct nft_set_elem *e, void *data), void *data); diff --git a/include/libnftables/table.h b/include/libnftables/table.h index 42a4aa7..4a323bd 100644 --- a/include/libnftables/table.h +++ b/include/libnftables/table.h @@ -1,6 +1,7 @@ #ifndef _TABLE_H_ #define _TABLE_H_ +#include #include #include @@ -48,6 +49,7 @@ enum nft_table_parse_type { int nft_table_parse(struct nft_table *t, enum nft_table_parse_type type, const char *data); int nft_table_snprintf(char *buf, size_t size, struct nft_table *t, uint32_t type, uint32_t flags); +int nft_table_fprintf(FILE *fp, struct nft_table *t, uint32_t type, uint32_t flags); struct nlmsghdr *nft_table_nlmsg_build_hdr(char *buf, uint16_t cmd, uint16_t family, uint16_t type, uint32_t seq); int nft_table_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_table *t); diff --git a/src/chain.c b/src/chain.c index 6179f68..cdb398f 100644 --- a/src/chain.c +++ b/src/chain.c @@ -851,6 +851,19 @@ int nft_chain_snprintf(char *buf, size_t size, struct nft_chain *c, } EXPORT_SYMBOL(nft_chain_snprintf); +static inline int nft_chain_do_snprintf(char *buf, size_t size, void *c, + uint32_t type, uint32_t flags) +{ + return nft_chain_snprintf(buf, size, c, type, flags); +} + +int nft_chain_fprintf(FILE *fp, struct nft_chain *c, uint32_t type, + uint32_t flags) +{ + return nft_fprintf(fp, c, type, flags, nft_chain_do_snprintf); +} +EXPORT_SYMBOL(nft_chain_fprintf); + struct nft_chain_list { struct list_head list; }; diff --git a/src/internal.h b/src/internal.h index b29288a..6449a9f 100644 --- a/src/internal.h +++ b/src/internal.h @@ -17,6 +17,8 @@ #define BASE_DEC 10 #define BASE_HEX 16 +#define NFT_SNPRINTF_BUFSIZ 4096 + enum nft_type { NFT_TYPE_U8, NFT_TYPE_U16, @@ -88,6 +90,8 @@ const char *nft_verdict2str(uint32_t verdict); int nft_str2verdict(const char *verdict); int nft_get_value(enum nft_type type, void *val, void *out); +int nft_fprintf(FILE *fp, void *obj, uint32_t type, uint32_t flags, int (*snprintf_cb)(char *buf, size_t bufsiz, void *obj, uint32_t type, uint32_t flags)); + void xfree(const void *ptr); struct expr_ops; diff --git a/src/libnftables.map b/src/libnftables.map index 1223403..aa47714 100644 --- a/src/libnftables.map +++ b/src/libnftables.map @@ -12,6 +12,7 @@ global: nft_table_attr_get_str; nft_table_parse; nft_table_snprintf; + nft_table_fprintf; nft_table_nlmsg_build_hdr; nft_table_nlmsg_build_payload; nft_table_nlmsg_parse; @@ -42,6 +43,7 @@ global: nft_chain_attr_get_str; nft_chain_parse; nft_chain_snprintf; + nft_chain_fprintf; nft_chain_nlmsg_build_hdr; nft_chain_nlmsg_build_payload; nft_chain_nlmsg_parse; @@ -71,6 +73,7 @@ global: nft_rule_attr_get_str; nft_rule_parse; nft_rule_snprintf; + nft_rule_fprintf; nft_rule_nlmsg_build_hdr; nft_rule_nlmsg_build_payload; nft_rule_nlmsg_parse; @@ -126,6 +129,7 @@ global: nft_set_nlmsg_parse; nft_set_parse; nft_set_snprintf; + nft_set_fprintf; nft_set_list_alloc; nft_set_list_free; @@ -157,6 +161,7 @@ global: nft_set_elem_nlmsg_parse; nft_set_elem_parse; nft_set_elem_snprintf; + nft_set_elem_fprinf; nft_set_elems_nlmsg_build_payload; nft_set_elems_nlmsg_parse; @@ -176,6 +181,7 @@ global: nft_ruleset_attr_get; nft_ruleset_parse; nft_ruleset_snprintf; + nft_ruleset_fprintf; local: *; }; diff --git a/src/rule.c b/src/rule.c index d135f38..3b45dc7 100644 --- a/src/rule.c +++ b/src/rule.c @@ -819,6 +819,19 @@ int nft_rule_snprintf(char *buf, size_t size, struct nft_rule *r, } EXPORT_SYMBOL(nft_rule_snprintf); +static inline int nft_rule_do_snprintf(char *buf, size_t size, void *r, + uint32_t type, uint32_t flags) +{ + return nft_rule_snprintf(buf, size, r, type, flags); +} + +int nft_rule_fprintf(FILE *fp, struct nft_rule *r, uint32_t type, + uint32_t flags) +{ + return nft_fprintf(fp, r, type, flags, nft_rule_do_snprintf); +} +EXPORT_SYMBOL(nft_rule_fprintf); + int nft_rule_expr_foreach(struct nft_rule *r, int (*cb)(struct nft_rule_expr *e, void *data), void *data) diff --git a/src/ruleset.c b/src/ruleset.c index 24b849b..ee2c60a 100644 --- a/src/ruleset.c +++ b/src/ruleset.c @@ -813,3 +813,206 @@ int nft_ruleset_snprintf(char *buf, size_t size, const struct nft_ruleset *r, } } EXPORT_SYMBOL(nft_ruleset_snprintf); + +static int nft_ruleset_fprintf_tables(FILE *fp, const struct nft_ruleset *rs, + uint32_t type, uint32_t flags) +{ + int len = 0, ret = 0; + struct nft_table *t; + struct nft_table_list_iter *ti; + + ti = nft_table_list_iter_create(rs->table_list); + if (ti == NULL) + return -1; + + t = nft_table_list_iter_next(ti); + while (t != NULL) { + ret = nft_table_fprintf(fp, t, type, flags); + if (ret < 0) + goto err; + + len += ret; + + t = nft_table_list_iter_next(ti); + + ret = fprintf(fp, "%s", nft_ruleset_o_separator(t, type)); + if (ret < 0) + goto err; + + len += ret; + } + nft_table_list_iter_destroy(ti); + + return len; +err: + nft_table_list_iter_destroy(ti); + return -1; +} + +static int nft_ruleset_fprintf_chains(FILE *fp, const struct nft_ruleset *rs, + uint32_t type, uint32_t flags) +{ + int len = 0, ret = 0; + struct nft_chain *o; + struct nft_chain_list_iter *i; + + i = nft_chain_list_iter_create(rs->chain_list); + if (i == NULL) + return -1; + + o = nft_chain_list_iter_next(i); + while (o != NULL) { + ret = nft_chain_fprintf(fp, o, type, flags); + if (ret < 0) + goto err; + + len += ret; + + o = nft_chain_list_iter_next(i); + + ret = fprintf(fp, "%s", nft_ruleset_o_separator(o, type)); + if (ret < 0) + goto err; + + len += ret; + } + nft_chain_list_iter_destroy(i); + + return len; +err: + nft_chain_list_iter_destroy(i); + return -1; +} + +static int nft_ruleset_fprintf_sets(FILE *fp, const struct nft_ruleset *rs, + uint32_t type, uint32_t flags) +{ + int len = 0, ret = 0; + struct nft_set *o; + struct nft_set_list_iter *i; + + i = nft_set_list_iter_create(rs->set_list); + if (i == NULL) + return -1; + + o = nft_set_list_iter_next(i); + while (o != NULL) { + ret = nft_set_fprintf(fp, o, type, flags); + if (ret < 0) + goto err; + + len += ret; + + o = nft_set_list_iter_next(i); + + ret = fprintf(fp, "%s", nft_ruleset_o_separator(o, type)); + if (ret < 0) + goto err; + + len += ret; + } + nft_set_list_iter_destroy(i); + + return len; +err: + nft_set_list_iter_destroy(i); + return -1; +} + +static int nft_ruleset_fprintf_rules(FILE *fp, const struct nft_ruleset *rs, + uint32_t type, uint32_t flags) +{ + int len = 0, ret = 0; + struct nft_rule *o; + struct nft_rule_list_iter *i; + + i = nft_rule_list_iter_create(rs->rule_list); + if (i == NULL) + return -1; + + o = nft_rule_list_iter_next(i); + while (o != NULL) { + ret = nft_rule_fprintf(fp, o, type, flags); + if (ret < 0) + goto err; + + len += ret; + + o = nft_rule_list_iter_next(i); + + ret = fprintf(fp, "%s", nft_ruleset_o_separator(o, type)); + if (ret < 0) + goto err; + + len += ret; + } + nft_rule_list_iter_destroy(i); + + return len; +err: + nft_rule_list_iter_destroy(i); + return -1; +} + +#define NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len) \ + if (ret < 0) \ + return -1; \ + len += ret; + +int nft_ruleset_fprintf(FILE *fp, const struct nft_ruleset *rs, uint32_t type, + uint32_t flags) +{ + int len = 0, ret = 0; + void *prev = NULL; + + ret = fprintf(fp, "%s", nft_ruleset_o_opentag(type)); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + if ((nft_ruleset_attr_is_set(rs, NFT_RULESET_ATTR_TABLELIST)) && + (!nft_table_list_is_empty(rs->table_list))) { + ret = nft_ruleset_fprintf_tables(fp, rs, type, flags); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + if (ret > 0) + prev = rs->table_list; + } + + if ((nft_ruleset_attr_is_set(rs, NFT_RULESET_ATTR_CHAINLIST)) && + (!nft_chain_list_is_empty(rs->chain_list))) { + ret = fprintf(fp, "%s", nft_ruleset_o_separator(prev, type)); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + ret = nft_ruleset_fprintf_chains(fp, rs, type, flags); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + if (ret > 0) + prev = rs->chain_list; + } + + if ((nft_ruleset_attr_is_set(rs, NFT_RULESET_ATTR_SETLIST)) && + (!nft_set_list_is_empty(rs->set_list))) { + ret = fprintf(fp, "%s", nft_ruleset_o_separator(prev, type)); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + ret = nft_ruleset_fprintf_sets(fp, rs, type, flags); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + if (ret > 0) + prev = rs->set_list; + } + + if ((nft_ruleset_attr_is_set(rs, NFT_RULESET_ATTR_RULELIST)) && + (!nft_rule_list_is_empty(rs->rule_list))) { + ret = fprintf(fp, "%s", nft_ruleset_o_separator(prev, type)); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + ret = nft_ruleset_fprintf_rules(fp, rs, type, flags); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + } + + ret = fprintf(fp, "%s", nft_ruleset_o_closetag(type)); + NFT_FPRINTF_RETURN_OR_FIXLEN(ret, len); + + return len; +} +EXPORT_SYMBOL(nft_ruleset_fprintf); diff --git a/src/set.c b/src/set.c index 2c6e6a6..9620006 100644 --- a/src/set.c +++ b/src/set.c @@ -668,6 +668,19 @@ int nft_set_snprintf(char *buf, size_t size, struct nft_set *s, } EXPORT_SYMBOL(nft_set_snprintf); +static inline int nft_set_do_snprintf(char *buf, size_t size, void *s, + uint32_t type, uint32_t flags) +{ + return nft_set_snprintf(buf, size, s, type, flags); +} + +int nft_set_fprintf(FILE *fp, struct nft_set *s, uint32_t type, + uint32_t flags) +{ + return nft_fprintf(fp, s, type, flags, nft_set_do_snprintf); +} +EXPORT_SYMBOL(nft_set_fprintf); + void nft_set_elem_add(struct nft_set *s, struct nft_set_elem *elem) { list_add_tail(&elem->head, &s->element_list); diff --git a/src/set_elem.c b/src/set_elem.c index 5ef46f2..516905d 100644 --- a/src/set_elem.c +++ b/src/set_elem.c @@ -577,6 +577,19 @@ int nft_set_elem_snprintf(char *buf, size_t size, struct nft_set_elem *e, } EXPORT_SYMBOL(nft_set_elem_snprintf); +static inline int nft_set_elem_do_snprintf(char *buf, size_t size, void *e, + uint32_t type, uint32_t flags) +{ + return nft_set_elem_snprintf(buf, size, e, type, flags); +} + +int nft_set_elem_fprintf(FILE *fp, struct nft_set_elem *se, uint32_t type, + uint32_t flags) +{ + return nft_fprintf(fp, se, type, flags, nft_set_elem_do_snprintf); +} +EXPORT_SYMBOL(nft_set_elem_fprintf); + int nft_set_elem_foreach(struct nft_set *s, int (*cb)(struct nft_set_elem *e, void *data), void *data) diff --git a/src/table.c b/src/table.c index d3ff188..d1acc7c 100644 --- a/src/table.c +++ b/src/table.c @@ -388,6 +388,19 @@ int nft_table_snprintf(char *buf, size_t size, struct nft_table *t, } EXPORT_SYMBOL(nft_table_snprintf); +static inline int nft_table_do_snprintf(char *buf, size_t size, void *t, + uint32_t type, uint32_t flags) +{ + return nft_table_snprintf(buf, size, t, type, flags); +} + +int nft_table_fprintf(FILE *fp, struct nft_table *t, uint32_t type, + uint32_t flags) +{ + return nft_fprintf(fp, t, type, flags, nft_table_do_snprintf); +} +EXPORT_SYMBOL(nft_table_fprintf); + struct nft_table_list { struct list_head list; }; diff --git a/src/utils.c b/src/utils.c index 9a0bcfe..2415917 100644 --- a/src/utils.c +++ b/src/utils.c @@ -174,3 +174,30 @@ void xfree(const void *ptr) { free((void *)ptr); } + +int nft_fprintf(FILE *fp, void *obj, uint32_t type, uint32_t flags, + int (*snprintf_cb)(char *buf, size_t bufsiz, void *obj, + uint32_t type, uint32_t flags)) +{ + char _buf[NFT_SNPRINTF_BUFSIZ]; + char *buf = _buf; + size_t bufsiz = sizeof(_buf); + int ret; + + ret = snprintf_cb(buf, bufsiz, obj, type, flags); + if (ret > NFT_SNPRINTF_BUFSIZ) { + buf = calloc(1, ret); + if (buf == NULL) + return -1; + + bufsiz = ret; + ret = snprintf_cb(buf, bufsiz, obj, type, flags); + } + + ret = fprintf(fp, "%s", buf); + + if (buf != _buf) + xfree(buf); + + return ret; +} -- cgit v1.2.3