OPENSSL_MALLOC(3)

💅 OPENSSL_MALLOC(3) 💅

okay so bestie, this is OPENSSL_MALLOC(3) from the Library Functions Manual — and yes, it's literally the legacy memory-allocation wrapper page for libcrypto. Short page, real lore, let's get into it. 🫶

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🌸 NAME 🌸

OPENSSL_malloc, OPENSSL_free, OPENSSL_strdup, CRYPTO_malloc, CRYPTO_free, CRYPTO_strdup — the legacy OpenSSL memory allocation wrappers. That's the whole squad, no cap. ✨

✨ SYNOPSIS ✨

here's the exact code, bestie — signatures copied character for character, because we do not play with types around here:

library “libcrypto” #include <openssl/crypto.h>

void *
OPENSSL_malloc(size_t num);

void
OPENSSL_free(void *addr);

char *
OPENSSL_strdup(const char *str);

void *
CRYPTO_malloc(size_t num, const char *file, int line);

void
CRYPTO_free(void *str, const char *, int);

char *
CRYPTO_strdup(const char *p, const char *file, int line);

🦋 DESCRIPTION 🦋

🚨 the big rule first: do not use any of the interfaces documented here in new code. They are provided purely for compatibility with legacy application code. It's giving museum exhibit, not new-build energy. 💀

These functions are wrappers around the corresponding standard malloc(3), free(3), and strdup(3) functions.

The OPENSSL_*() functions are implemented as macros. iconic behavior, honestly. 💅

🎀 RETURN VALUES 🎀

These functions return the same type and value as the corresponding standard functions. that's it, that's the tea. 🍓

👑 SEE ALSO 👑

• crypto(3)

one reference, one icon. 🌟

💜 HISTORY 💜

• CRYPTO_malloc() and CRYPTO_free() first appeared in SSLeay 0.6.4 and have been available since OpenBSD 2.4.
• OPENSSL_malloc() and OPENSSL_free() first appeared in OpenSSL 0.9.6 and have been available since OpenBSD 2.9.
• CRYPTO_strdup() and OPENSSL_strdup() first appeared in OpenSSL 0.9.8j and have been available since OpenBSD 4.5.

so yes, these are old old. vintage, even. 🧚

🔥 CAVEATS 🔥

If interoperability with other implementations is required, memory returned by the library as bare pointers must be freed with OPENSSL_free().

like, do not mix up your frees, bestie. if interop with other implementations matters, bare pointers from the library must go back through OPENSSL_free(). periodt. 😭

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with love from Debian, dated June 8, 2025 — OPENSSL_MALLOC(3), mwah 💋