MEDIUM: regex: Remove null terminated strings.

The new regex function can use string and length. The HAproxy buffer are
not null-terminated, and the use of the regex_exec* functions implies
the add of this null character. This patch replace these function by the
functions which takes a string and length as input.

Just the file "proto_http.c" is change because this one is more executed
than other. The file "checks.c" have a very low usage, and it is not
interesting to change it. Furthermore, the buffer used by "checks.c" are
null-terminated.

diff --git a/src/proto_http.c b/src/proto_http.c
index e61f51274e4bdeaead02ed1e0c9799a5e55a4b20..52319a907103fd5b263285dc0181aaedc8cb837e 100644 (file)
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -3179,10 +3179,10 @@ static inline void inet_set_tos(int fd, struct sockaddr_storage from, int tos)
 /* Returns the number of characters written to destination,
  * -1 on internal error and -2 if no replacement took place.
  */
-static int http_replace_header(struct my_regex *re, char *dst, uint dst_size, char *val,
+static int http_replace_header(struct my_regex *re, char *dst, uint dst_size, char *val, int len,
                                const char *rep_str)
 {
-       if (!regex_exec_match(re, val, MAX_MATCH, pmatch))
+       if (!regex_exec_match2(re, val, len, MAX_MATCH, pmatch))
                return -2;
 
        return exp_replace(dst, dst_size, val, rep_str, pmatch);
@@ -3191,7 +3191,7 @@ static int http_replace_header(struct my_regex *re, char *dst, uint dst_size, ch
 /* Returns the number of characters written to destination,
  * -1 on internal error and -2 if no replacement took place.
  */
-static int http_replace_value(struct my_regex *re, char *dst, uint dst_size, char *val, char delim,
+static int http_replace_value(struct my_regex *re, char *dst, uint dst_size, char *val, int len, char delim,
                               const char *rep_str)
 {
        char* p = val;
@@ -3200,16 +3200,13 @@ static int http_replace_value(struct my_regex *re, char *dst, uint dst_size, cha
 
        for (;;) {
                char *p_delim;
-               const char* tok_end;
 
-               if ((p_delim = (char*)strchr(p, delim))) {
-                       *p_delim = 0;
-                       tok_end = p_delim;
-               } else {
-                       tok_end = p + strlen(p);
-               }
+               /* look for delim. */
+               p_delim = p;
+               while (p_delim < p + len && *p_delim != delim)
+                       p_delim++;
 
-               if (regex_exec_match(re, p, MAX_MATCH, pmatch)) {
+               if (regex_exec_match2(re, p, p_delim-p, MAX_MATCH, pmatch)) {
                        int replace_n = exp_replace(dst_p, dst_end - dst_p, p, rep_str, pmatch);
 
                        if (replace_n < 0)
@@ -3217,7 +3214,7 @@ static int http_replace_value(struct my_regex *re, char *dst, uint dst_size, cha
 
                        dst_p += replace_n;
                } else {
-                       uint len = tok_end - p;
+                       uint len = p_delim - p;
 
                        if (dst_p + len >= dst_end)
                                return -1;
@@ -3229,14 +3226,13 @@ static int http_replace_value(struct my_regex *re, char *dst, uint dst_size, cha
                if (dst_p >= dst_end)
                        return -1;
 
-               if (p_delim) {
-                       *p_delim = delim;
-                       *dst_p++ = delim;
-                       p = p_delim + 1;
-               } else {
-                       *dst_p = 0;
+               /* end of the replacements. */
+               if (p_delim >= p + len)
                        break;
-               }
+
+               /* Next part. */
+               *dst_p++ = delim;
+               p = p_delim + 1;
        }
 
        return dst_p - dst;
@@ -3253,12 +3249,10 @@ static int http_transform_header(struct session* s, struct http_msg *msg, const
                int delta;
                char* val = (char*)ctx->line + name_len + 2;
                char* val_end = (char*)ctx->line + hdr->len;
-               char save_val_end = *val_end;
                char* reg_dst_buf;
                uint reg_dst_buf_size;
                int n_replaced;
 
-               *val_end = 0;
                trash.len = build_logline(s, trash.str, trash.size, fmt);
 
                if (trash.len >= trash.size - 1)
@@ -3270,18 +3264,16 @@ static int http_transform_header(struct session* s, struct http_msg *msg, const
                switch (action) {
                case HTTP_REQ_ACT_REPLACE_VAL:
                case HTTP_RES_ACT_REPLACE_VAL:
-                       n_replaced = http_replace_value(re, reg_dst_buf, reg_dst_buf_size, val, ',', trash.str);
+                       n_replaced = http_replace_value(re, reg_dst_buf, reg_dst_buf_size, val, val_end-val, ',', trash.str);
                        break;
                case HTTP_REQ_ACT_REPLACE_HDR:
                case HTTP_RES_ACT_REPLACE_HDR:
-                       n_replaced = http_replace_header(re, reg_dst_buf, reg_dst_buf_size, val, trash.str);
+                       n_replaced = http_replace_header(re, reg_dst_buf, reg_dst_buf_size, val, val_end-val, trash.str);
                        break;
                default: /* impossible */
                        return -1;
                }
 
-               *val_end = save_val_end;
-
                switch (n_replaced) {
                case -1: return -1;
                case -2: continue;
@@ -6882,7 +6874,6 @@ int http_response_forward_body(struct session *s, struct channel *res, int an_bi
  */
 int apply_filter_to_req_headers(struct session *s, struct channel *req, struct hdr_exp *exp)
 {
-       char term;
        char *cur_ptr, *cur_end, *cur_next;
        int cur_idx, old_idx, last_hdr;
        struct http_txn *txn = &s->txn;
@@ -6916,15 +6907,7 @@ int apply_filter_to_req_headers(struct session *s, struct channel *req, struct h
                 * and the next header starts at cur_next.
                 */
 
-               /* The annoying part is that pattern matching needs
-                * that we modify the contents to null-terminate all
-                * strings before testing them.
-                */
-
-               term = *cur_end;
-               *cur_end = '\0';
-
-               if (regex_exec_match(exp->preg, cur_ptr, MAX_MATCH, pmatch)) {
+               if (regex_exec_match2(exp->preg, cur_ptr, cur_end-cur_ptr, MAX_MATCH, pmatch)) {
                        switch (exp->action) {
                        case ACT_SETBE:
                                /* It is not possible to jump a second time.
@@ -6985,8 +6968,6 @@ int apply_filter_to_req_headers(struct session *s, struct channel *req, struct h
 
                        }
                }
-               if (cur_end)
-                       *cur_end = term; /* restore the string terminator */
 
                /* keep the link from this header to next one in case of later
                 * removal of next header.
@@ -7005,7 +6986,6 @@ int apply_filter_to_req_headers(struct session *s, struct channel *req, struct h
  */
 int apply_filter_to_req_line(struct session *s, struct channel *req, struct hdr_exp *exp)
 {
-       char term;
        char *cur_ptr, *cur_end;
        int done;
        struct http_txn *txn = &s->txn;
@@ -7028,15 +7008,7 @@ int apply_filter_to_req_line(struct session *s, struct channel *req, struct hdr_
 
        /* Now we have the request line between cur_ptr and cur_end */
 
-       /* The annoying part is that pattern matching needs
-        * that we modify the contents to null-terminate all
-        * strings before testing them.
-        */
-
-       term = *cur_end;
-       *cur_end = '\0';
-
-       if (regex_exec_match(exp->preg, cur_ptr, MAX_MATCH, pmatch)) {
+       if (regex_exec_match2(exp->preg, cur_ptr, cur_end-cur_ptr, MAX_MATCH, pmatch)) {
                switch (exp->action) {
                case ACT_SETBE:
                        /* It is not possible to jump a second time.
@@ -7067,7 +7039,6 @@ int apply_filter_to_req_line(struct session *s, struct channel *req, struct hdr_
                        break;
 
                case ACT_REPLACE:
-                       *cur_end = term; /* restore the string terminator */
                        trash.len = exp_replace(trash.str, trash.size, cur_ptr, exp->replace, pmatch);
                        if (trash.len < 0)
                                return -1;
@@ -7096,7 +7067,6 @@ int apply_filter_to_req_line(struct session *s, struct channel *req, struct hdr_
                        return 1;
                }
        }
-       *cur_end = term; /* restore the string terminator */
        return done;
 }
 
@@ -7766,7 +7736,6 @@ void manage_client_side_cookies(struct session *s, struct channel *req)
  */
 int apply_filter_to_resp_headers(struct session *s, struct channel *rtr, struct hdr_exp *exp)
 {
-       char term;
        char *cur_ptr, *cur_end, *cur_next;
        int cur_idx, old_idx, last_hdr;
        struct http_txn *txn = &s->txn;
@@ -7799,15 +7768,7 @@ int apply_filter_to_resp_headers(struct session *s, struct channel *rtr, struct
                 * and the next header starts at cur_next.
                 */
 
-               /* The annoying part is that pattern matching needs
-                * that we modify the contents to null-terminate all
-                * strings before testing them.
-                */
-
-               term = *cur_end;
-               *cur_end = '\0';
-
-               if (regex_exec_match(exp->preg, cur_ptr, MAX_MATCH, pmatch)) {
+               if (regex_exec_match2(exp->preg, cur_ptr, cur_end-cur_ptr, MAX_MATCH, pmatch)) {
                        switch (exp->action) {
                        case ACT_ALLOW:
                                txn->flags |= TX_SVALLOW;
@@ -7850,8 +7811,6 @@ int apply_filter_to_resp_headers(struct session *s, struct channel *rtr, struct
 
                        }
                }
-               if (cur_end)
-                       *cur_end = term; /* restore the string terminator */
 
                /* keep the link from this header to next one in case of later
                 * removal of next header.
@@ -7868,7 +7827,6 @@ int apply_filter_to_resp_headers(struct session *s, struct channel *rtr, struct
  */
 int apply_filter_to_sts_line(struct session *s, struct channel *rtr, struct hdr_exp *exp)
 {
-       char term;
        char *cur_ptr, *cur_end;
        int done;
        struct http_txn *txn = &s->txn;
@@ -7891,15 +7849,7 @@ int apply_filter_to_sts_line(struct session *s, struct channel *rtr, struct hdr_
 
        /* Now we have the status line between cur_ptr and cur_end */
 
-       /* The annoying part is that pattern matching needs
-        * that we modify the contents to null-terminate all
-        * strings before testing them.
-        */
-
-       term = *cur_end;
-       *cur_end = '\0';
-
-       if (regex_exec_match(exp->preg, cur_ptr, MAX_MATCH, pmatch)) {
+       if (regex_exec_match2(exp->preg, cur_ptr, cur_end-cur_ptr, MAX_MATCH, pmatch)) {
                switch (exp->action) {
                case ACT_ALLOW:
                        txn->flags |= TX_SVALLOW;
@@ -7912,7 +7862,6 @@ int apply_filter_to_sts_line(struct session *s, struct channel *rtr, struct hdr_
                        break;
 
                case ACT_REPLACE:
-                       *cur_end = term; /* restore the string terminator */
                        trash.len = exp_replace(trash.str, trash.size, cur_ptr, exp->replace, pmatch);
                        if (trash.len < 0)
                                return -1;
@@ -7941,7 +7890,6 @@ int apply_filter_to_sts_line(struct session *s, struct channel *rtr, struct hdr_
                        return 1;
                }
        }
-       *cur_end = term; /* restore the string terminator */
        return done;
 }