+#include "misc.h"
+
+/*
+ * Parse a string block size specification. This is approximately a
+ * subset of the block size specs supported by GNU fileutils:
+ * "nk" = n kilobytes
+ * "nM" = n megabytes
+ * "nG" = n gigabytes
+ * All numbers are decimal, and suffixes refer to powers of two.
+ * Case-insensitive.
+ */
+unsigned long parse_blocksize(const char *bs)
+{
+ char *suf;
+ unsigned long r = strtoul(bs, &suf, 10);
+ if (*suf != '\0') {
+ while (*suf && isspace((unsigned char)*suf)) suf++;
+ switch (*suf) {
+ case 'k': case 'K':
+ r *= 1024ul;
+ break;
+ case 'm': case 'M':
+ r *= 1024ul * 1024ul;
+ break;
+ case 'g': case 'G':
+ r *= 1024ul * 1024ul * 1024ul;
+ break;
+ case '\0':
+ default:
+ break;
+ }
+ }
+ return r;
+}
+
+/*
+ * Parse a ^C style character specification.
+ * Returns NULL in `next' if we didn't recognise it as a control character,
+ * in which case `c' should be ignored.
+ * The precise current parsing is an oddity inherited from the terminal
+ * answerback-string parsing code. All sequences start with ^; all except
+ * ^<123> are two characters. The ones that are worth keeping are probably:
+ * ^? 127
+ * ^@A-Z[\]^_ 0-31
+ * a-z 1-26
+ * <num> specified by number (decimal, 0octal, 0xHEX)
+ * ~ ^ escape
+ */
+char ctrlparse(char *s, char **next)
+{
+ char c = 0;
+ if (*s != '^') {
+ *next = NULL;
+ } else {
+ s++;
+ if (*s == '\0') {
+ *next = NULL;
+ } else if (*s == '<') {
+ s++;
+ c = (char)strtol(s, next, 0);
+ if ((*next == s) || (**next != '>')) {
+ c = 0;
+ *next = NULL;
+ } else
+ (*next)++;
+ } else if (*s >= 'a' && *s <= 'z') {
+ c = (*s - ('a' - 1));
+ *next = s+1;
+ } else if ((*s >= '@' && *s <= '_') || *s == '?' || (*s & 0x80)) {
+ c = ('@' ^ *s);
+ *next = s+1;
+ } else if (*s == '~') {
+ c = '^';
+ *next = s+1;
+ }
+ }
+ return c;
+}
+
+/*
+ * Find a character in a string, unless it's a colon contained within
+ * square brackets. Used for untangling strings of the form
+ * 'host:port', where host can be an IPv6 literal.
+ *
+ * We provide several variants of this function, with semantics like
+ * various standard string.h functions.
+ */
+static const char *host_strchr_internal(const char *s, const char *set,
+ int first)
+{
+ int brackets = 0;
+ const char *ret = NULL;
+
+ while (1) {
+ if (!*s)
+ return ret;
+
+ if (*s == '[')
+ brackets++;
+ else if (*s == ']' && brackets > 0)
+ brackets--;
+ else if (brackets && *s == ':')
+ /* never match */ ;
+ else if (strchr(set, *s)) {
+ ret = s;
+ if (first)
+ return ret;
+ }
+
+ s++;
+ }
+}
+size_t host_strcspn(const char *s, const char *set)
+{
+ const char *answer = host_strchr_internal(s, set, TRUE);
+ if (answer)
+ return answer - s;
+ else
+ return strlen(s);
+}
+char *host_strchr(const char *s, int c)
+{
+ char set[2];
+ set[0] = c;
+ set[1] = '\0';
+ return (char *) host_strchr_internal(s, set, TRUE);
+}
+char *host_strrchr(const char *s, int c)
+{
+ char set[2];
+ set[0] = c;
+ set[1] = '\0';
+ return (char *) host_strchr_internal(s, set, FALSE);
+}
+
+#ifdef TEST_HOST_STRFOO
+int main(void)
+{
+ int passes = 0, fails = 0;
+
+#define TEST1(func, string, arg2, suffix, result) do \
+ { \
+ const char *str = string; \
+ unsigned ret = func(string, arg2) suffix; \
+ if (ret == result) { \
+ passes++; \
+ } else { \
+ printf("fail: %s(%s,%s)%s = %u, expected %u\n", \
+ #func, #string, #arg2, #suffix, ret, result); \
+ fails++; \
+ } \
+} while (0)
+
+ TEST1(host_strchr, "[1:2:3]:4:5", ':', -str, 7);
+ TEST1(host_strrchr, "[1:2:3]:4:5", ':', -str, 9);
+ TEST1(host_strcspn, "[1:2:3]:4:5", "/:",, 7);
+ TEST1(host_strchr, "[1:2:3]", ':', == NULL, 1);
+ TEST1(host_strrchr, "[1:2:3]", ':', == NULL, 1);
+ TEST1(host_strcspn, "[1:2:3]", "/:",, 7);
+ TEST1(host_strcspn, "[1:2/3]", "/:",, 4);
+ TEST1(host_strcspn, "[1:2:3]/", "/:",, 7);
+
+ printf("passed %d failed %d total %d\n", passes, fails, passes+fails);
+ return fails != 0 ? 1 : 0;
+}
+/* Stubs to stop the rest of this module causing compile failures. */
+void modalfatalbox(const char *fmt, ...) {}
+int conf_get_int(Conf *conf, int primary) { return 0; }
+char *conf_get_str(Conf *conf, int primary) { return NULL; }
+#endif /* TEST_HOST_STRFOO */
+
+/*
+ * Trim square brackets off the outside of an IPv6 address literal.
+ * Leave all other strings unchanged. Returns a fresh dynamically
+ * allocated string.
+ */
+char *host_strduptrim(const char *s)
+{
+ if (s[0] == '[') {
+ const char *p = s+1;
+ int colons = 0;
+ while (*p && *p != ']') {
+ if (isxdigit((unsigned char)*p))
+ /* OK */;
+ else if (*p == ':')
+ colons++;
+ else
+ break;
+ p++;
+ }
+ if (*p == ']' && !p[1] && colons > 1) {
+ /*
+ * This looks like an IPv6 address literal (hex digits and
+ * at least two colons, contained in square brackets).
+ * Trim off the brackets.
+ */
+ return dupprintf("%.*s", (int)(p - (s+1)), s+1);
+ }
+ }
+
+ /*
+ * Any other shape of string is simply duplicated.
+ */
+ return dupstr(s);
+}
+
+prompts_t *new_prompts(void *frontend)
+{
+ prompts_t *p = snew(prompts_t);
+ p->prompts = NULL;
+ p->n_prompts = 0;
+ p->frontend = frontend;
+ p->data = NULL;
+ p->to_server = TRUE; /* to be on the safe side */
+ p->name = p->instruction = NULL;
+ p->name_reqd = p->instr_reqd = FALSE;
+ return p;
+}
+void add_prompt(prompts_t *p, char *promptstr, int echo)
+{
+ prompt_t *pr = snew(prompt_t);
+ pr->prompt = promptstr;
+ pr->echo = echo;
+ pr->result = NULL;
+ pr->resultsize = 0;
+ p->n_prompts++;
+ p->prompts = sresize(p->prompts, p->n_prompts, prompt_t *);
+ p->prompts[p->n_prompts-1] = pr;
+}
+void prompt_ensure_result_size(prompt_t *pr, int newlen)
+{
+ if ((int)pr->resultsize < newlen) {
+ char *newbuf;
+ newlen = newlen * 5 / 4 + 512; /* avoid too many small allocs */
+
+ /*
+ * We don't use sresize / realloc here, because we will be
+ * storing sensitive stuff like passwords in here, and we want
+ * to make sure that the data doesn't get copied around in
+ * memory without the old copy being destroyed.
+ */
+ newbuf = snewn(newlen, char);
+ memcpy(newbuf, pr->result, pr->resultsize);
+ smemclr(pr->result, pr->resultsize);
+ sfree(pr->result);
+ pr->result = newbuf;
+ pr->resultsize = newlen;
+ }
+}
+void prompt_set_result(prompt_t *pr, const char *newstr)
+{
+ prompt_ensure_result_size(pr, strlen(newstr) + 1);
+ strcpy(pr->result, newstr);
+}
+void free_prompts(prompts_t *p)
+{
+ size_t i;
+ for (i=0; i < p->n_prompts; i++) {
+ prompt_t *pr = p->prompts[i];
+ smemclr(pr->result, pr->resultsize); /* burn the evidence */
+ sfree(pr->result);
+ sfree(pr->prompt);
+ sfree(pr);
+ }
+ sfree(p->prompts);
+ sfree(p->name);
+ sfree(p->instruction);
+ sfree(p);
+}
+
+/* ----------------------------------------------------------------------
+ * String handling routines.
+ */
+
+char *dupstr(const char *s)
+{
+ char *p = NULL;
+ if (s) {
+ int len = strlen(s);
+ p = snewn(len + 1, char);
+ strcpy(p, s);
+ }
+ return p;
+}
+
+/* Allocate the concatenation of N strings. Terminate arg list with NULL. */
+char *dupcat(const char *s1, ...)
+{
+ int len;
+ char *p, *q, *sn;
+ va_list ap;
+
+ len = strlen(s1);
+ va_start(ap, s1);
+ while (1) {
+ sn = va_arg(ap, char *);
+ if (!sn)
+ break;
+ len += strlen(sn);
+ }
+ va_end(ap);
+
+ p = snewn(len + 1, char);
+ strcpy(p, s1);
+ q = p + strlen(p);
+
+ va_start(ap, s1);
+ while (1) {
+ sn = va_arg(ap, char *);
+ if (!sn)
+ break;
+ strcpy(q, sn);
+ q += strlen(q);
+ }
+ va_end(ap);
+
+ return p;
+}
+
+void burnstr(char *string) /* sfree(str), only clear it first */
+{
+ if (string) {
+ smemclr(string, strlen(string));
+ sfree(string);
+ }
+}
+
+int toint(unsigned u)
+{
+ /*
+ * Convert an unsigned to an int, without running into the
+ * undefined behaviour which happens by the strict C standard if
+ * the value overflows. You'd hope that sensible compilers would
+ * do the sensible thing in response to a cast, but actually I
+ * don't trust modern compilers not to do silly things like
+ * assuming that _obviously_ you wouldn't have caused an overflow
+ * and so they can elide an 'if (i < 0)' test immediately after
+ * the cast.
+ *
+ * Sensible compilers ought of course to optimise this entire
+ * function into 'just return the input value'!
+ */
+ if (u <= (unsigned)INT_MAX)
+ return (int)u;
+ else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */
+ return INT_MIN + (int)(u - (unsigned)INT_MIN);
+ else
+ return INT_MIN; /* fallback; should never occur on binary machines */
+}
+
+/*
+ * Do an sprintf(), but into a custom-allocated buffer.
+ *
+ * Currently I'm doing this via vsnprintf. This has worked so far,
+ * but it's not good, because vsnprintf is not available on all
+ * platforms. There's an ifdef to use `_vsnprintf', which seems
+ * to be the local name for it on Windows. Other platforms may
+ * lack it completely, in which case it'll be time to rewrite
+ * this function in a totally different way.
+ *
+ * The only `properly' portable solution I can think of is to
+ * implement my own format string scanner, which figures out an
+ * upper bound for the length of each formatting directive,
+ * allocates the buffer as it goes along, and calls sprintf() to
+ * actually process each directive. If I ever need to actually do
+ * this, some caveats:
+ *
+ * - It's very hard to find a reliable upper bound for
+ * floating-point values. %f, in particular, when supplied with
+ * a number near to the upper or lower limit of representable
+ * numbers, could easily take several hundred characters. It's
+ * probably feasible to predict this statically using the
+ * constants in <float.h>, or even to predict it dynamically by
+ * looking at the exponent of the specific float provided, but
+ * it won't be fun.
+ *
+ * - Don't forget to _check_, after calling sprintf, that it's
+ * used at most the amount of space we had available.
+ *
+ * - Fault any formatting directive we don't fully understand. The
+ * aim here is to _guarantee_ that we never overflow the buffer,
+ * because this is a security-critical function. If we see a
+ * directive we don't know about, we should panic and die rather
+ * than run any risk.
+ */
+char *dupprintf(const char *fmt, ...)
+{
+ char *ret;
+ va_list ap;
+ va_start(ap, fmt);
+ ret = dupvprintf(fmt, ap);
+ va_end(ap);
+ return ret;
+}
+char *dupvprintf(const char *fmt, va_list ap)
+{
+ char *buf;
+ int len, size;
+
+ buf = snewn(512, char);
+ size = 512;
+
+ while (1) {
+#ifdef _WINDOWS
+#define vsnprintf _vsnprintf
+#endif
+#ifdef va_copy
+ /* Use the `va_copy' macro mandated by C99, if present.
+ * XXX some environments may have this as __va_copy() */
+ va_list aq;
+ va_copy(aq, ap);
+ len = vsnprintf(buf, size, fmt, aq);
+ va_end(aq);
+#else
+ /* Ugh. No va_copy macro, so do something nasty.
+ * Technically, you can't reuse a va_list like this: it is left
+ * unspecified whether advancing a va_list pointer modifies its
+ * value or something it points to, so on some platforms calling
+ * vsnprintf twice on the same va_list might fail hideously
+ * (indeed, it has been observed to).
+ * XXX the autoconf manual suggests that using memcpy() will give
+ * "maximum portability". */
+ len = vsnprintf(buf, size, fmt, ap);
+#endif
+ if (len >= 0 && len < size) {
+ /* This is the C99-specified criterion for snprintf to have
+ * been completely successful. */
+ return buf;
+ } else if (len > 0) {
+ /* This is the C99 error condition: the returned length is
+ * the required buffer size not counting the NUL. */
+ size = len + 1;
+ } else {
+ /* This is the pre-C99 glibc error condition: <0 means the
+ * buffer wasn't big enough, so we enlarge it a bit and hope. */
+ size += 512;
+ }
+ buf = sresize(buf, size, char);
+ }
+}
+
+/*
+ * Read an entire line of text from a file. Return a buffer
+ * malloced to be as big as necessary (caller must free).
+ */
+char *fgetline(FILE *fp)
+{
+ char *ret = snewn(512, char);
+ int size = 512, len = 0;
+ while (fgets(ret + len, size - len, fp)) {
+ len += strlen(ret + len);
+ if (ret[len-1] == '\n')
+ break; /* got a newline, we're done */
+ size = len + 512;
+ ret = sresize(ret, size, char);
+ }
+ if (len == 0) { /* first fgets returned NULL */
+ sfree(ret);
+ return NULL;
+ }
+ ret[len] = '\0';
+ return ret;
+}
+
+/*
+ * Perl-style 'chomp', for a line we just read with fgetline. Unlike
+ * Perl chomp, however, we're deliberately forgiving of strange
+ * line-ending conventions. Also we forgive NULL on input, so you can
+ * just write 'line = chomp(fgetline(fp));' and not bother checking
+ * for NULL until afterwards.
+ */
+char *chomp(char *str)
+{
+ if (str) {
+ int len = strlen(str);
+ while (len > 0 && (str[len-1] == '\r' || str[len-1] == '\n'))
+ len--;
+ str[len] = '\0';
+ }
+ return str;
+}
+
+/* ----------------------------------------------------------------------
+ * Core base64 encoding and decoding routines.
+ */
+
+void base64_encode_atom(const unsigned char *data, int n, char *out)
+{
+ static const char base64_chars[] =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+ unsigned word;
+
+ word = data[0] << 16;
+ if (n > 1)
+ word |= data[1] << 8;
+ if (n > 2)
+ word |= data[2];
+ out[0] = base64_chars[(word >> 18) & 0x3F];
+ out[1] = base64_chars[(word >> 12) & 0x3F];
+ if (n > 1)
+ out[2] = base64_chars[(word >> 6) & 0x3F];
+ else
+ out[2] = '=';
+ if (n > 2)
+ out[3] = base64_chars[word & 0x3F];
+ else
+ out[3] = '=';
+}
+
+int base64_decode_atom(const char *atom, unsigned char *out)
+{
+ int vals[4];
+ int i, v, len;
+ unsigned word;
+ char c;
+
+ for (i = 0; i < 4; i++) {
+ c = atom[i];
+ if (c >= 'A' && c <= 'Z')
+ v = c - 'A';
+ else if (c >= 'a' && c <= 'z')
+ v = c - 'a' + 26;
+ else if (c >= '0' && c <= '9')
+ v = c - '0' + 52;
+ else if (c == '+')
+ v = 62;
+ else if (c == '/')
+ v = 63;
+ else if (c == '=')
+ v = -1;
+ else
+ return 0; /* invalid atom */
+ vals[i] = v;
+ }
+
+ if (vals[0] == -1 || vals[1] == -1)
+ return 0;
+ if (vals[2] == -1 && vals[3] != -1)
+ return 0;
+
+ if (vals[3] != -1)
+ len = 3;
+ else if (vals[2] != -1)
+ len = 2;
+ else
+ len = 1;
+
+ word = ((vals[0] << 18) |
+ (vals[1] << 12) | ((vals[2] & 0x3F) << 6) | (vals[3] & 0x3F));
+ out[0] = (word >> 16) & 0xFF;
+ if (len > 1)
+ out[1] = (word >> 8) & 0xFF;
+ if (len > 2)
+ out[2] = word & 0xFF;
+ return len;
+}
+
+/* ----------------------------------------------------------------------
+ * Generic routines to deal with send buffers: a linked list of
+ * smallish blocks, with the operations
+ *
+ * - add an arbitrary amount of data to the end of the list
+ * - remove the first N bytes from the list
+ * - return a (pointer,length) pair giving some initial data in
+ * the list, suitable for passing to a send or write system
+ * call
+ * - retrieve a larger amount of initial data from the list
+ * - return the current size of the buffer chain in bytes
+ */
+
+#define BUFFER_MIN_GRANULE 512
+
+struct bufchain_granule {
+ struct bufchain_granule *next;
+ char *bufpos, *bufend, *bufmax;
+};
+
+void bufchain_init(bufchain *ch)
+{
+ ch->head = ch->tail = NULL;
+ ch->buffersize = 0;
+}