crypto_stdrng_get_bytes(9)

💖 crypto_stdrng_get_bytes — bestie's guide to cryptographically secure random bytes 💖

okay so this is a page from the Kernel API Manual (section 9, kernel-API girlies rise 🫶) and it's literally all about grabbing some top-tier random bytes. no cap, this one's short and sweet, so let's get into it ✨

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🌸 NAME 🌸

crypto_stdrng_get_bytes — get cryptographically secure random bytes 💅

like, actually secure. not your cousin's rand(). the real deal.

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✨ SYNOPSIS ✨

int crypto_stdrng_get_bytes (void *buf , unsigned int len );

that's the whole signature, bestie — copy it exactly, she's particular about her types 🔥

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🎀 ARGUMENTS 🎀

• buf — your output buffer, aka where the random numbers go to live. it's caller-allocated, so yes, you're bringing the container, the function's just bringing the goodies 🍓
• len — the length of that output buffer. how much randomness are we talking here 🌈

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🦋 DESCRIPTION 🦋

okay so here's the vibe check 👑: this function fills the caller-allocated buffer with random numbers. easy enough. but which random numbers? that's the fun part:

• if fips_enabled=0, it uses the normal Linux RNG — the classic, the icon, the main character 💅
• if fips_enabled=1, it switches to the highest-priority "stdrng" algorithm in the crypto_rng subsystem — FIPS mode has entered the chat, we're being ✨responsible✨ now

so it's giving "one function, two moods," and the mood is decided entirely by that fips_enabled flag. iykyk 🧚

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🫶 CONTEXT 🫶

May sleep. 😴

that's it, that's the whole section. so don't go calling this from somewhere that can't take a nap — noted, respected, moving on 🌸

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⭐ RETURN ⭐

• 0 — the function was successful, we ate, no crumbs 💖
• < 0 — an error occurred 😭 something went wrong, check that value fr fr

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💜 SEE ALSO 💜

• Kernel file ./include/crypto/rng.h struct rng_alg(9)
• Random number generator API(9)
• crypto_alloc_rng(9)
• crypto_rng_alg(9)
• crypto_free_rng(9)
• crypto_rng_generate(9)
• crypto_rng_get_bytes(9)
• crypto_rng_reset(9)
• crypto_rng_seedsize(9)

like, the whole crypto_rng friend group honestly. go say hi to all of them 🦋

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ngl this one's genuinely simple — fill buffer, respect fips_enabled, check the return value. but do check the return value, bestie, don't leave me hanging 😭

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and that's the page! 💅 brought to you from the ./include/crypto corner of the kernel, dated October 2026 — so mark your calendar, she's from the future ✨🎀 stay random, stay secure, mwah 💖